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  • 2010-2014  (24)
  • 1960-1964  (1,637)
  • 1920-1924  (688)
  • 1905-1909  (334)
  • Cell & Developmental Biology  (2,659)
  • ddc:510  (24)
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  • 1
    Publication Date: 2020-12-11
    Description: Convexity is an important property in nonlinear optimization since it allows to apply efficient local methods for finding global solutions. We propose to apply symbolic methods to prove or disprove convexity of rational functions over a polyhedral domain. Our algorithms reduce convexity questions to real quantifier elimination problems. Our methods are implemented and publicly available in the open source computer algebra system REDUCE. Our long term goal is to integrate REDUCE as a workhorse'' for symbolic computations into a numerical solver.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 2
    Publication Date: 2016-06-30
    Description: Applications which need exclusive access to a shared resource in distributed systems require a fault-tolerant and scalable mechanism to coordinate this exclusive access. Examples of such applications include distributed file systems and master/slave data replication. We present Flease, an algorithm for decentralized and fault-tolerant lease coordination in distributed systems. Our algorithm allows the processes competing for a resource to coordinate exclusive access through leases among themselves without a central component. The resulting system easily scales with an increasing number of nodes and resources. We prove that Flease ensures exclusive access, i.e. guarantees that there is at most one valid lease at any time.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 3
    Publication Date: 2020-08-05
    Description: We propose an efficient column generation method to minimize the probability of delay propagations along aircraft rotations. In this way, delay resistant schedules can be constructed. Computational results for large-scale real-world problems demonstrate substantial punctuality improvements. The method can be generalized to crew and integrated scheduling problems.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 4
    Publication Date: 2022-01-07
    Description: In optimal control problems with nonlinear time-dependent 3D PDEs, full 4D discretizations are usually prohibitive due to the storage requirement. For this reason gradient and quasi-Newton methods working on the reduced functional are often employed. The computation of the reduced gradient requires one solve of the state equation forward in time, and one backward solve of the adjoint equation. The state enters into the adjoint equation, again requiring the storage of a full 4D data set. We propose a lossy compression algorithm using an inexact but cheap predictor for the state data, with additional entropy coding of prediction errors. As the data is used inside a discretized, iterative algorithm, lossy coding maintaining an error bound is sufficient.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 5
    Publication Date: 2020-03-11
    Description: Bovine fertility is the subject of extensive research in animal sciences, especially because fertility of dairy cows has declined during the last decades. The regulation of estrus is controlled by the complex interplay of various organs and hormones. Mathematical modeling of the bovine estrous cycle could help in understanding the dynamics of this complex biological system. In this paper we present a mathematical model of the bovine estrous cycle that includes the processes of follicle and corpus luteum development and the key hormones that interact to control these processes. Focus in this paper is on development of the model, but also some simulation results are presented, showing that a set of equations and parameters is obtained that describes the system consistent with empirical knowledge. Even though the majority of the mechanisms that are included are only known qualitatively as stimulatory or inhibitory effects, the model surprisingly well features quantitative observations made in reality. This model of the bovine estrous cycle could be used as a basis for more elaborate models with the ability to study effects of external manipulations and genetic differences.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 6
    Publication Date: 2022-03-14
    Description: Learning during search allows solvers for discrete optimization problems to remember parts of the search that they have already performed and avoid revisiting redundant parts. Learning approaches pioneered by the SAT and CP communities have been successfully incorporated into the SCIP constraint integer programming platform. In this paper we show that performing a heuristic constraint programming search during root node processing of a binary program can rapidly learn useful nogoods, bound changes, primal solutions, and branching statistics that improve the remaining IP search.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 7
    Publication Date: 2020-08-05
    Description: We propose a novel integer programming approach to transfer minimization for line planning problems in public transit. The idea is to incorporate penalties for transfers that are induced by “connection capacities” into the construction of the passenger paths. We show that such penalties can be dealt with by a combination of shortest and constrained shortest path algorithms such that the pricing problem for passenger paths can be solved efficiently. Connection capacity penalties (under)estimate the true transfer times. This error is, however, not a problem in practice. We show in a computational comparison with two standard models on a real-world scenario that our approach can be used to minimize passenger travel and transfer times for large-scale line planning problems with accurate results.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 8
    Publication Date: 2016-06-09
    Description: The aim of this paper is to devise an adaptive timestep control in the contact--stabilized Newmark method (CONTACX) for dynamical contact problems between two viscoelastic bodies in the framework of Signorini's condition. In order to construct a comparative scheme of higher order accuracy, we extend extrapolation techniques. This approach demands a subtle theoretical investigation of an asymptotic error expansion of the contact--stabilized Newmark scheme. On the basis of theoretical insight and numerical observations, we suggest an error estimator and a timestep selection which also cover the presence of contact. Finally, we give a numerical example.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 9
    Publication Date: 2020-08-05
    Description: Railway scheduling is based on the principle of the construction of a conflict-free timetable. This leads to a strict definition of capacity: in contrast with road transportation, it can be said in advance whether a given railway infrastructure can accommodate - at least in theory - a certain set of train requests. Consequently, auctions for railway capacity are modeled as auctions of discrete goods -- the train slots. We present estimates for the efficiency gain that may be generated by slot auctioning in comparison with list price allocation. We introduce a new class of allocation and auction problems, the feasible assignment problem, that is a proper generalization of the well-known combinatorial auction problem. The feasible assignment class was designed to cover the needs for an auction mechanism for railway slot auctions, but is of interest in its own right. As a practical instance to state and solve the railway slot allocation problem, we present an integer programming formulation, briefly the ACP, which turns out to be an instance of the feasible assignment problem and whose dual problem yields prices that can be applied to define a useful activity rule for the linearized version of the Ausubel Milgrom Proxy auction. We perform a simulation aiming to measure the impact on efficiency and convergence rate.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 10
    Publication Date: 2022-01-07
    Description: This paper presents concepts and implementation of the finite element toolbox Kaskade 7, a flexible C++ code for solving elliptic and parabolic PDE systems. Issues such as problem formulation, assembly and adaptivity are discussed at the example of optimal control problems. Trajectory compression for parabolic optimization problems is considered as a case study.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 11
    Publication Date: 2020-08-05
    Description: In this paper a bottom-up approach of automatic simplification of a railway network is presented. Starting from a very detailed, microscopic level, as it is used in railway simulation, the network is transformed by an algorithm to a less detailed level (macroscopic network), that is sufficient for long-term planning and optimization. In addition running and headway times are rounded to a pre-chosen time discretization by a special cumulative method, which we will present and analyse in this paper. After the transformation we fill the network with given train requests to compute an optimal slot allocation. Then the optimized schedule is re-transformed into the microscopic level and can be simulated without any conflicts occuring between the slots. The algorithm is used to transform the network of the very dense Simplon corridor between Swiss and Italy. With our aggregation it is possible for the first time to generate a profit maximal and conflict free timetable for the corridor across a day by a simultaneously optimization run.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 12
    Publication Date: 2020-12-11
    Description: In solving large polynomial algebraic systems that are too big for standard Gröbner basis techniques one way to make progress is to introduce case distinctions. This divide and conquer technique can be beneficial if the algorithms and computer programs know how to take advantage of inequalities. A further hurdle is the form of the resulting general solutions which often have unnecessarily many branches. In this paper we discuss a procedure to merge solutions by dropping inequalities which are associated with them and, if necessary, by re-parametrizing solutions. In the appendix the usefulness of the procedure is demonstrated in the classification of quadratic Hamiltonians with a Lie-Poisson bracket $e(3)$. This application required the solution of algebraic systems with over 200 unknowns, 450 equations and between 5000 and 9000 terms.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 13
    Publication Date: 2020-12-11
    Description: In the paper arguments are given why the concept of static evaluation (SE) has the potential to be a useful extension to Monte Carlo tree search. A new concept of modeling SE through a dynamical system is introduced and strengths and weaknesses are discussed. The general suitability of this approach is demonstrated. A Remark: Among users of the Internet Go server KGS the abbreviation SE is used for 'Score Estimator'. Although different from 'Static Evaluation' a score estimator is easily obtained from static evaluation by adding up probabilities of chains to be alive at the end of the game or points to be owned by White or Black
    Keywords: ddc:510
    Language: English
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  • 14
    Publication Date: 2020-12-11
    Description: Linear Poisson brackets on e(3) typical of rigid body dynamics are considered. All quadratic Hamiltonians of Kowalevski type having additional first integral of fourth degree are found. Quantum analogs of these Hamiltonians are listed.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 15
    Publication Date: 2020-12-11
    Description: A classification problem is proposed for supersymmetric %scaling\/-\/in\-va\-ri\-ant evolutionary PDE that satisfy the assumptions of nonlinearity, nondegeneracy, and homogeneity. Four classes of nonlinear coupled boson\/-\/fermion systems are discovered under the weighting assumption $|f|=|b|=|D_t|=\oh$. The syntax of the \Reduce\ package \SsTools, which was used for intermediate computations, and the applicability of its procedures to the calculus of super\/-\/PDE are described.
    Keywords: ddc:510
    Language: English
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  • 16
    Publication Date: 2020-12-11
    Description: We consider the problem of constructing Gardner's deformations for the $N{=}2$ supersymmetric $a{=}4$--\/Korteweg\/--\/de Vries equation; such deformations yield recurrence relations between the super\/-\/Hamiltonians of the hierarchy. We prove the non\/-\/existence %P.~Mathieu's Open problem on constructing for of supersymmetry\/-\/invariant %Gardner's deformations that %solutions, retract to Gardner's formulas for the KdV equation %whenever it is assumed that, under the %respective component reduction. % in the $N{=}2$ super\/-\/field. the solutions . At the same time, we propose a two\/-\/step scheme for the recursive production of the integrals of motion for the $N{=}2$,\ $a{=}4$--\/SKdV. First, we find a new Gardner's deformation of the Kaup\/--\/Boussinesq equation, which is contained in the bosonic limit of the super\/-\/%$N{=}2$,\ $a{=}4$--\/SKdV hierarchy. This yields the recurrence relation between the Hamiltonians of the limit, whence we determine the bosonic super\/- /Hamiltonians of the full $N{=}2$, $a{=}4$--\/SKdV hierarchy.
    Keywords: ddc:510
    Language: English
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  • 17
    Publication Date: 2020-08-05
    Description: We provide an introduction into the mathematics of and with paths. Not on the shortest, but hopefully on an entertaining path!
    Keywords: ddc:510
    Language: English
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  • 18
    Publication Date: 2020-08-05
    Description: Wir stellen in dieser Arbeit ein mathematisches Optimierungsmodell zur Bestimmung eines optimalen Linienplans vor, das sowohl die Fahrzeiten und die Anzahl der Umstiege berücksichtigt als auch die Kosten des Liniennetzes. Dieses Modell deckt wichtige praktische Anforderungen ab, die in einem gemeinsamen Projekt mit den Verkehrsbetrieben in Potsdam (ViP) formuliert wurden. In diesem Projekt wurde der Linienplan 2010 für Potsdam entwickelt. Unsere Berechnungen zeigen, dass die mathematische Optimierung in nichts einer "Handplanung" des Liniennetzes nachsteht. Im Gegenteil, mit Hilfe des Optimierungsprogramms ist es möglich, durch Veränderung der Parameter mehrere verschiedene Szenarien zu berechnen, miteinander zu vergleichen und Aussagen über minimale Kosten und Fahrzeiten zu machen.
    Keywords: ddc:510
    Language: German
    Type: reportzib , doc-type:preprint
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  • 19
    Publication Date: 2020-12-11
    Description: The paper gathers evidence showing different dimensions of the game of Go: the continuous and discrete nature of the game and different types of relations between state variables happening on ultra local, local, regional, and global scales. Based on these observations a new continuous local model for describing a board position is introduced. This includes the identification of the basic variables describing a board position and the formulation and solution of a dynamical system for their computation. To be usable as a static evaluation function for a game playing program at least group-wide (regional)aspects will have to be incorporated.
    Keywords: ddc:510
    Language: English
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  • 20
    Publication Date: 2020-08-05
    Description: The track allocation problem, also known as train routing problem or train timetabling problem, is to find a conflict-free set of train routes of maximum value in a railway network. Although it can be modeled as a standard path packing problem, instances of sizes relevant for real-world railway applications could not be solved up to now. We propose a rapid branching column generation approach that integrates the solution of the LP relaxation of a path coupling formulation of the problem with a special rounding heuristic. The approach is based on and exploits special properties of the bundle method for the approximate solution of convex piecewise linear functions. Computational results for difficult instances of the benchmark library TTPLIB are reported.
    Keywords: ddc:510
    Language: English
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  • 21
    Publication Date: 2020-08-05
    Description: This paper presents a case study on a railway timetable optimization for the very dense Simplon corridor, a major railway connection in the Alps between Switzerland and Italy. Starting from a detailed microscopic network as it is used in railway simulation, the data is transformed by an automatic procedure to a less detailed macroscopic network, that is sufficient for the purpose of capacity planning and amenable to state-of-the-art integer programming optimization methods. In this way, the macroscopic railway network is saturated with trains. Finally, the corresponding timetable is re-transformed to the microscopic level in such a way that it can be operated without any conflicts among the slots. Using this integer programming based micro-macro aggregation-disaggregation approach, it becomes for the first time possible to generate a profit maximal and conflict free timetable for the complete Simplon corridor over an entire day by a simultaneous optimization of all trains requests. This also allows to to undertake a sensitivity analysis of various problem parameters.
    Keywords: ddc:510
    Language: English
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  • 22
    Publication Date: 2016-06-09
    Description: The thesis presents the analysis of a reduced model for modulation of internal gravity waves by deep convective clouds. The starting point for the derivation are conservation laws for mass, momentum and energy coupled with a bulk micro-physics model describing the evolution of mixing ratios of water vapor, cloud water and rain water. A reduced model for the identified scales of the regime is derived, using multi-scale asymptotics. The closure of the model employs conditional averaging over the horizontal scale of the convective clouds. The resulting reduced model is an extension of the anelastic equations, linearized around a constant background state, which are well-known from meteorology. The closure of the model is achieved purely by analytical means and involves no additional physically motivated assumptions. The essential new parameter arising from the coupling to a micro-physics model is the area fraction of saturated regions on the horizontal scale of the convective clouds. It turns out that this parameter is constant on the employed short timescale. Hence the clouds constitute a constant background, modulating the characteristics of propagation of internal waves. The model is then investigated by analytical as well as numerical means. Important results are, among others, that in the model moisture (i) inhibits propagation of internal waves by reducing the modulus of the group velocity, (ii) reduces the angle between the propagation direction of a wave-packet and the horizontal, (iii) causes critical layers and (iv) introduces a maximum horizontal wavelength beyond which waves are no longer propagating but become evanescent. The investigated examples of orographically generated gravity waves also feature a significant reduction of vertical momentum flux by moisture. The model is extended by assuming systematically small under-saturation, that is saturation at leading order. The closure is similar to the original case but requires additional assumptions. The saturated area fraction in the obtained model is no longer constant but now depends nonlinearly on vertical displacement and thus on vertical velocity.
    Keywords: ddc:510
    Language: English
    Type: doctoralthesis , doc-type:doctoralThesis
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  • 23
    Publication Date: 2022-03-14
    Description: We propose a hybrid approach for solving the resource-constrained project scheduling problem which is an extremely hard to solve combinatorial optimization problem of practical relevance. Jobs have to be scheduled on (renewable) resources subject to precedence constraints such that the resource capacities are never exceeded and the latest completion time of all jobs is minimized. The problem has challenged researchers from different communities, such as integer programming (IP), constraint programming (CP), and satisfiability testing (SAT). Still, there are instances with 60 jobs which have not been solved for many years. The currently best known approach, lazyFD, is a hybrid between CP and SAT techniques. In this paper we propose an even stronger hybridization by integrating all the three areas, IP, CP, and SAT, into a single branch-and-bound scheme. We show that lower bounds from the linear relaxation of the IP formulation and conflict analysis are key ingredients for pruning the search tree. First computational experiments show very promising results. For five instances of the well-known PSPLIB we report an improvement of lower bounds. Our implementation is generic, thus it can be potentially applied to similar problems as well.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 24
    Publication Date: 2023-11-03
    Description: In contrast to the well known meshbased methods like the finite element method, meshfree methods do not rely on a mesh. However besides their great applicability, meshfree methods are rather time consuming. Thus, it seems favorable to combine both methods, by using meshfree methods only in a small part of the domain, where a mesh is disadvantageous, and a meshbased method for the rest of the domain. We motivate, that this coupling between the two simulation techniques can be considered as saddle point problem and show the stability of this coupling. Thereby a novel transfer operator is introduced, which interacts in the transition zone, where both methods coexist.
    Keywords: ddc:510
    Language: English
    Type: reportzib , doc-type:preprint
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  • 25
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
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  • 26
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 149 (1964), S. 309-312 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In the normal parathyroid gland of the mouse there is only one type of cell which is small with a large nucleus and small amount of cytoplasm. In order to investigate the effect of relaxin on parathyroid histology, mice were injected with relaxin, the degree of pubic separation was measured by the x-ray technique, and the parathyroid glands were studied histologically. After one day of relaxin injection, the pubic symphysis showed a distinct separation and in part of the parathyroid gland the cells were larger and stained lighter and pinker than the normal cells with hematoxylin, eosin, and azur II. After four days of relaxin treatment, the whole gland had changed so that all the cells were of the second type. Glands of pregnant mice near term also were composed of cells of this type. These results indicate a relationship between relaxin and the parathyroid gland.
    Additional Material: 1 Tab.
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  • 27
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Thalidomide injury to an implanted armadillo blastocyst is presented. This finding confirms the specific damage by thalidomide to the embryoblastic cells. The lack of damage to the trophoblast at this stage permits a normal implantation of the blastocyst in the uterine mucosa.
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  • 28
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 149 (1964), S. 181-189 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Although melanoctyes appear to be limited to the hair folicles of adult belly skin of the PET mouse, they are found throughout the integument of the newborn. Trauma applied to the ventral belly skin of newborn PET mice results in the maintenance and augmentation of the melanocytes within the skin, even after the formation and growth of hair. The area immediately surrounding the site of trauma shows an increase in the number of melanocytes, apparently due in part to the disruption of the developing follicles and the consequent release of their pigment cells to the skin. UV irradiation also maintains a system of melanocytes within the ventral belly skin of PET mice.The significance of the maintenance and augmentation of melanocytes from the newborn into the adult by surgical trauma or UV radiation is discussed.
    Additional Material: 1 Ill.
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  • 29
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The histology of the anterior hypophysis, thyroid and gonads of dwarf (dw) and Ames dwarf (df) mutants of Mus musculus was compared. Orange G, aldehyde fuchsin and PAS stains were used to differentiate cells of the hypophysis. In both types of dwarf the anterior hypophysis was small, acidophils were lacking and the number of thyrotropic hormone producing cells was reduced. The thyroids were reduced in size, the follicles were small and some tissue was not organized into follicles. Testes were nearly normal. Ovaries were small and large follicles and corpora lutea were lacking.Growth hormone (STH) and thyrotropic hormone (TSH) were administered to both types of dwarfs. The treatment had no effect on the anterior hypophysis but number and size of follicles in the thyroid was increased The response was greater in df dwarfs; STH and TSH had more effect than STH alone. Testes of treated mice were only slightly changed but most of the df and some dw males became fertile. The ovaries became large and functional. Thyroids of dwarfs treated with thyroxine were not changed.It is concluded that the primary hormone deficiencies in both types of dwarf are the same, but that there are physiological differences as revealed by responses to STH and TSH treatment.
    Additional Material: 2 Tab.
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  • 30
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: This study was undertaken to determine the relationship between Marshall's metalophilic reticular cells and the cells exhibiting non-specific esterase and acid phosphatase activity in the rat spleen. Untreated and stimulated animals were used. Observations were made chiefly on the marginal metalophils of Snook. These cells showed strong acid phosphatase activity but only slight non-specific esterase activity in untreated animals. Following stimulation non-specific esterase activity increased in these cells. Within the nodules metalophilic reticular cells were always more numerous than cells with enzyme activity. Many of these metalophilic cells developed enzyme activity following stimulation. By the use of a restaining technique it was shown that all reticular cells possessing enzyme activity were also metalophilic but that the converse was not true. No mitotic activity was present in these cells.The results suggest that Marshall's metalophils are cells of the reticuloendothelial system in various stages of maturation and that, following stimulation, they may differentiate into mature phagocytic cells.
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  • 31
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 149 (1964) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 32
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Densities of the various bone fractions i.e., water, organic, volatile inorganic and ash fractions, as well as fat in the various animals have been studied. However. values reported by various workers failed to show consistency and uniformity, especially with respect to the volatile inorganic (often called “CO2 fraction”) and the ash fractions. These densities are prerequisite to the study of the volumetric composition of bone and bone marrow.In our study, the fat and organic densities found were similar to those previously reported. The volatile and non-volatile inorganic (ash) fractions, had density values of 1.684 and 3.180, respectively. The ash density was much higher than values previously reported but it verifies a theoretical value deduced by the authors from published work.Our higher ash density was due to a smaller measured volume of this fraction obtained by applying a negative pressure to remove the small entrapped air bubbles from the ash sample prior to the water displacement measurement. Because a smaller portion of the total inorganic volume was used for the ash calculation, giving it a higher density, a larger balance of the total inorganic volume was left for the volatile inorganic density calculation. This accounted for ash and volatile inorganic densities which were higher and lower, respectively, than such values previously reported.Prior to the determination of the density of the non-volatile inorganic fraction, the ashing time and temperature were studied. Curves plotted from the results of such studies were described and explained.
    Additional Material: 3 Ill.
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  • 33
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The two uterine horns in the adult are joined caudally to form an externally undivided segment consisting of a cranial and a caudal part. The cranial part becomes wide and swollen at its junction with the horns. It contains two lumina separated by a midline septum and is designated as the uterine body or corpus. The narrow and slightly tapered caudal part projects into the cranial portion of the vagina. It contains a single lumen or canal and is designated as the uterine neck or cervix. The wall of the cranial two-thirds of the adult cervix contains a relatively large amount of circularly arranged smooth muscle fibers. In contrast, its caudal one-third consists chiefly of a network of collagen fibers. During cervical development argyrophilic fibers first appear in sections of cervical wall from mice sacrificed at birth. Collagen and smooth muscle fibers are first stainable with the Mallory method in cervical wall sections from mice one week old. During pregnancy and after combined treatment with estradiol, progesterone and relaxin the collagenous fiber bundles of the cervix become looser and more widely separated. This is associated with an increased dilatability of the cervical canal and increased stainability of the ground substance. The muccopolysaccharide(s) demonstrable histochemically in the cervix of the mouse was digestible with testicular hyaluronidase.
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  • 34
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 150 (1964) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 35
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The in situ thymus of the guinea pig was labeled locally with H3-thymidine and sections of various tissues analyzed by radioautography for the location of labeled cells which might have left the thymus from 30 minutes to three days after labeling. Labeled lymphocytes were located especially in the mesenteric lymph nodes and spleen, giving direct evidence for the migration of thymocytes under near-physiological conditions. Only a few cells were found in the bone marrow, and none in the liver. The identified cells were not seen to be undergoing subsequent proliferation, but about one-fourth of them were transforming to other cell types - plasma cells, heterophil granulocytes, reticular cells, and macrophages. The fate of another portion of the cells seemed to be loss to the gut lumen through the mucosa. These data suggest that a normal function of the thymus of the adult guinea pig is the proliferation of a population of pluripotential stem cells which, after migration to other tissues, may further differentiate under appropriate stimulus. Possible applications of the local labeling technique are indicated.
    Additional Material: 15 Ill.
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  • 36
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The rate of skeletal maturation as indicated by ossification of bony elements of the central and appendicular skeleton was compared in two groups of hypothyroid young rats, raised at 20°C and 30°C constant environment respectively.Hypothyroidism was induced by feeding 0.2% propylthiouracil mixed with the food in powdered form to pregnant rats starting on the fifteenth day of gestation and continuing this treatment to the suckling mother until their litters had reached weaning age.The appearance of epiphyseal centers, of carpal and tarsal centers, middle phalanges and femoral and tibial processes and caudal vertebrae 7-27 is delayed in hypothyroid newborn rats over that of normal controls. Hypothyroid rats raised at 20°C lag more severely behind the controls with respect to skeletal maturation, than do hypothyroid rats raised at 30°C. The latter are intermediate or in some instances their rate of skeletal maturation resembles that of the control group.The possible significance of the demonstration of diminished requirements for thyroid hormone by the developing rat for studies attempting to identify mechanisms of hormone action in development is briefly discussed.
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  • 37
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A cephalometric radiographic appraisal of vertical skull growth occurring during the interim of one year was made on 71 caucasoid males at the Baylor University College of Dentistry, Dallas, Texas. The subjects were from 22 to 34 years of age. The dimensions assessed were the total skull height, the anterior cranial height, total facial height, upper facial height. and lower facial height. A significant increase was shown to occur in all the dimensions over a period of one year except in the dimension of anterior cranial height. It was concluded that skull growth does occur in male adults after the age generally accepted as that of maturity.
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  • 38
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 150 (1964), S. 243-247 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: To ascertain the pathway (s) along which forces are conducted from the hand to the humerus in the human cadaver specially designed pressure sensitive transducers were introduced into the radio-capitular and ulnar-trochlear components of the elbow joint. A constant force was applied to the hand, and changes in electrical resistance and hence pressure across the elbow joint where recorded. It was observed that 57% of the force applied crossed the radio-capitular joint while 43% crossed the ulnar-trochlear joint. The pathway of this force transmission is discussed with particular reference to the involvement of the interosseous membrane.
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  • 39
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    The @Anatomical Record 150 (1964), S. 257-263 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Implants from the midbrain and cerebellum of neonatal rats were cultured in roller tubes for 20 to 30 days. The cultures were incubated in a tryptamine-tetrazolium solution which demonstrated the enzyme activity of monoamine oxidase (MAO) by the formation of a formazan precipitation. Some cultures were incubated without fixation, while others were fixed in a glutaraldehyde solution prior to incubation. The specificity of the reaction was controlled by withholding the substrate or by treatment of the cultures with an MAO inhibitor. An intracellular localization of the enzyme was observed in small and medium sized neurons, but was absent in the largest neurons. Neuroglial cells, including ependyma, and mesenchymal cells and phagocytes were MAO positive. The formazan granules were scattered throughout cell bodies and into cytoplasmic processes. Glutaraldehyde fixation of cultures prior to incubation for MAO preserved the details of cell structure and enhanced the differentiation of cell types. When fixed and unfixed cultures were compared, glutaraldehyde did not appear to interfere or interact with enzyme localization; however, there was evidence that this aldehyde might be interfering with MAO concentration, since a longer incubation period for prefixed tissue was required to obtain a formazan reaction comparable to that of unfixed cultures.
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  • 40
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Lymphatic plexuses from certain areas of serous cavities can be injected by a simple procedure which simulates the normal mechanism of absorption. Apparatus consists of a 500 ml filtration flask with side arm attached to a vacuum apparatus. Excised serous membranes are draped over the mouth of the flask and flooded with ink. Vacuum is applied intermittently, resulting in absorption and flow. The method can be applied to frozen and thawed tissue and is suitable for human autopsy material.
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  • 41
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 150 (1964), S. 363-364 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: An anomaly of the termination of the aorta is described which is apparently unique. The aorta divided directly into two internal iliac arteries and two external iliac arteries.
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  • 42
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 150 (1964), S. 383-390 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A simple method leading to growth and mitosis in over 95% of shortterm cultures of lymphocytes from the blood, lymph or thymus of the rat is described. The method which is modified from Moorhead's original technique (′60) employs standard tissue culture medium (Eagles MEM or TC no. 199), 20% fresh rat serum, washed lymphocytes, penicillin, and phytohemagglutinin-P (0.01 cm3/cm3 of culture of a 1:5 dilution of stock solution). Details of culture technique and factors contributing to growth failures are discussed.The chromosomes of male and female Lewis rats were studied in metaphase spreads of cultured cells. The karyotypes of these rats are presented and found to be in agreement with those recently reported by Hungerford and Nowell (′63).
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  • 43
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The first statistically significant decline in the mean number of young born to female golden hamsters occurred in the fourth litters. The decreased size of fifth litters was highly significant and few females bore six litters.Hamsters unilaterally ovariectomized at 30 days of age had a significantly lower number of litters containing live young during their lifetime. Despite increased unilateral ovulaton, they bore less than half as many total young per female as intact controls and fetal resorptions and stillbirths occurred at an earlier age.The results of matings during the period of reproductive decline were observed in females from the age of ten months until death or sacrifice at an advanced age. Final litters contained few young, some born dead. One or two subsequent pregnancies were of term length but all conceptuses were resorbed. Few females beyond 15 months of age had implantation sites and most of these resorbed. Regular four day estrous cycles continued until a terminal illness and matings resulted in pseudopregnancy. Blastocysts were found at four and one-half days of gestation in some old females but not at 6 to 8 days. Failure of implantation appeared to be due to an inadequate uterine decidual reaction in the old animals.It appeared from the above observations that decreasing uterine adaptability limited reproductive capacity in aging hamsters.
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  • 44
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Castrated and castrated and hypophysectomized female mice (BALB/c) were injected subcutaneously with estradiol-17β (0.5 μg or 1.0 μg/day) and progesterone (1.0 mg or 3 mg/day) in addition to prolactin (1.0 mg), oxytocin (1.0 IU) or growth hormone (1.0 mg), alone and in combination for 10 or 15 days. Twenty-four hours after the last hormonal treatment, tritiated thymidine (0.7 μc/gram body weight) was injected intravenously, and the mice sacrificed six hours later. Tissue from the inguinal mammary glands was removed and processed for radioautographic, histological and whole mount study.Radioautographs of hematoxylin stained sections of mammary tissue from each animal were selected. Under oil immersion, 2,000 epithelial cells were consecutively counted and the number of labeled cells noted. Results are expressed as the per cent of labeled epithelial cells.All hormonal treatment, except oxytocin alone, caused a significant increase in per cent of labeled cells as compared to castrated, untreated animals. The per cent of labeled cells depended, in general, on the dosage and duration of treatment. Combinations of growth hormone with estradiol-17β and progesterone did not augment epithelial proliferation. The addition of oxytocin or prolactin to the estradiol-17β (0.5 μg)  -  progesterone (1.0 mg) combination significantly increased the per cent of labeled cells.Prolactin, but not oxytocin, augmented epithelial proliferation in similarly treated castrated and hypophysectomized mice. Combinations of estradiol-17β (1.0 μg) and progesterone (3.0 mg) with oxytocin or prolactin did not significantly augment epithelial proliferation as compared to ovarian steroid treatment alone.
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  • 45
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    The @Anatomical Record 150 (1964), S. 503-504 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 46
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    The @Anatomical Record 150 (1964), S. 449-461 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The prenatal development of the mandibular joint in mice was studied in fetuses at 15 to 20 days insemination age. The ramus of the mandible can be delineated as early as the fifteenth day by distinct differences in the degree of condensation of mesenchyme at the site of the future joint. The future condylar process of the mandible can be recognized in its relationship to the external pterygoid muscle, inferior alveolar nerve, Meckel's cartilage, pre-cartilaginous alisphenoid process of the future basisphenoid bone, and the anlage of the squamosal bone with its zygomatic process.Differentiation is rapid through the twentieth day of gestation at which time the following major elements of the joint can be recognized: a fibrous intra-articular disc continuous with the tendon of the external pterygoid muscle; a vascular synovial mesenchyme with upper and lower synovial spaces; an ossified squamosal bone with a fibrous joint lining; and a well developed condylar process with good representation of differentiating cells in the zones of chondrification and ossification.Among the elements not yet evident, however, are (1) hemopoietic marrow in the condyle, (2) a constricted neck at the base of the condyle, and (3) a fibrous capsule or capsular ligament.
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  • 47
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Thin slices of rat liver, kidney, and M. rectus femoris and thin, flat pieces of albumin-gelatin gels (which approximated the tissue slices in mass, dimensions and protein content) were immersed in formalin solutions at various concentrations, in some cases with variable amounts of NaCl (0.11-0.25M) added, and in some cases buffered at pH values ranging from 3.5-7.0. The slices were weighed at frequent intervals for the first 20 hours of immersion. Weight changes occurred rapidly. With the exception of the neutral buffered formalin curves, three families of response curves were obtained for the three tissues. With both formalin and formalinsaline solutions weight gain was inversely proportional to the solute concentration, but the formaldehyde particles apparently are not involved osmotically. The total osmotic concentration of formalin solutions, therefore, is not a factor in the swelling or shrinking of tissue slices. The presence of contaminants could be responsible for the effective osmotic concentration observed with these solutions. The weight response of slices is influenced by the pH of the formalin. Although the response of the gel system to any particular solution was quantitatively greater, it was qualitatively the same as the tissue slice response.
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  • 48
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The numerical variations observed in the dentition of the northern sea lions, fur seals and seals are summarized as follows: (1) There is a reappearance of the right maxillary second molar in the northern sea lion dentition and of the first deciduous premolar in the fur seal dentition, which may be interpreted as examples of evolutionary recession towards the full mammalian dentition. (2) There is a complete tooth reduction of the molars in the sea lion dentition. (3) There is the presence of a “Dentes geminati” of the second premolar and the supernumerary tooth in the right upper jaw and of the supernumerary tooth between the second and third premolars in the left upper jaw of an adult fur seal, which may be associated with the division of the second premolar tooth germ. (4) There is an appearance of a pair of supernumerary teeth lying lingually to the root of lower permanent central (second) incisors, being of interest in suggesting that they are either the appearance of the successors of the recent central incisors or the reappearance of the permanent first incisors, in the fur seal dentition. (5) There is a tooth reduction in the permanent dental formula from \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm I}\,\frac{{\rm 3}}{{\rm 2}}{\rm C}\,\frac{{\rm 1}}{{\rm 1}}{\rm P}\,\frac{{\rm 4}}{{\rm 4}}{\rm M}\frac{{\rm 1}}{{\rm 1}}\,{\rm to}\,{\rm I}\,\frac{{\rm 3}}{{\rm 1}}{\rm C}\,\frac{{\rm 1}}{{\rm 1}}{\rm P}\,\frac{{\rm 3}}{{\rm 4}}{\rm M}\frac{{\rm 1}}{{\rm 1}} $\end{document} in the seal, which was associated with a “Dentes confusi” in the same category of the dentition.
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  • 49
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    The @Anatomical Record 148 (1964) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 50
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    The @Anatomical Record 148 (1964), S. 67-74 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Neuroanatomical nuclear configuration corresponding to the projection regions for the chorda tympani, the IXth, and the lingual nerves was studied in the cat thalamus by a combination of electrophysiological, stereotaxic, and histological techniques. Each of the three nerves innervating the tongue was dissected for stimulation in cats deeply anesthetized with Nembutal. Maps of the extent of the thalamic projection for a particular nerve were obtained by recording evoked potentials in the thalamus during the stimulation of one of these nerves. Such maps were correlated with the anatomical structures of the cat thalamus by reconstructing the recording sites from histological sections of the cat brain. It was found that the chorda tympani and the IXth nerve projection regions correspond closely to the ventromedial nuclear complex with slight encorachment on the lingual nerve projection region in the ventrobasal complex. The most medial portions of the taste nerve projection regions do not relay any tactile afferent impulses and the most lateral portion of the lingual nerve projection is not activated by impulses in the taste nerves. Therefore, it is suggested that the thalamic relay of taste is not coextensive with other lingual modalities in the cat thalamus but it has an independent representation in the ventromedial nuclear complex.
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  • 51
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Analysis of age changes in physical characteristics of mouse limb bones requires a sensitive, consistent and relatively simple apparatus for determination of transverse breaking strength. The developed instrument is essentially a one meter counter-balanced 4-to-1 lever with a tracked, motor-driven weight on its upper surface. At the beam's short end a loading tool impinges upward on a bone mounted in an adjacent holder; at the opposite end is a mercury switch connected to a relay halting the weight motor when fracture occurs. Bones, with proximal ends embedded in convex securing blocks of impression medium, may be positioned in a standard relationship to the holder, loading tool edge, and the balanced beam.Repetitive loading of a steel spring indicates instrument error of 1.8%. Preliminary tests with a random series of paired mouse femora show no significant difference between left and right bones. In the long-term study it will be possible to correlate physical strength with other characteristics of opposite bones.An air-gap capacitor across loading tool and bone holder and coupled to a variable frequency oscillator permits monitoring of specimen elasticity on a strip-chart recorder.
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  • 52
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    The @Anatomical Record 148 (1964), S. 103-109 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A malformed human fetus with multiple congenital anomalies including absence of an umbilical artery is described. These anomalies include malpositioning of the apex of the heart; a “mirror image” position of the liver; mal-rotation of the gut with absence of external demarcation into small and large intestine; failure of development of the cloacal region with imperforate anus and absence of a urethra; undescended testes and bilaterally mal-placed scrotal sacs, but the presence of a median phallus in spite of the failure of the ventral abdominal wall to develop fully.Factors known to influence the production of fetal anomalies in man and animals are discussed and a brief review of the literature on single umbilical arteries, which are known to be associated frequently with congenital anomalies, is given.
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  • 53
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Electron microscopic studies reveal that the red pulp of the rabbit spleen is composed of reticular cells, reticulum and elements of the blood circulating through it. The three types of reticular cells described follow no definite pattern as to types of spaces they line and are not always adjacent to a basement membrane. Similar or dissimilar cells may line a basement membrane on the same or opposing sides. The entire red pulp area is intercommunicating through pores and junctions of the several spaces and in that area in which no basement membrane exists, the cytoplasmic projections of the reticular cells form a meshwork of spaces. Terminal arterioles are seen to end in collapsed type channels with a change from endothelium to Type I reticular cells. These rapidly join dilated areas. The reticular network of the spleen appears as four types: homogeneous, fibrillar, a combination of these, and reticular cells only. Isolated cilia are found in the reticular cell cytoplasm and are shown to be associated with a basal body and a centriole. The investigation supported the hypothesis that the red pulp of the spleen in the adult rabbit is a functionally dynamic area constantly changing its histological structure, both regarding cells and state of the vascular channels.
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  • 54
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    The @Anatomical Record 148 (1964), S. 121-122 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 55
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    The @Anatomical Record 148 (1964) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 56
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    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 148 (1964) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 57
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Colloidal mercuric sulfide injected into the rete testis adhered to the stereocilia of the epithelial cells and subsequently moved into a highly developed canalicular system in the apical cytoplasm. The canalicular invaginations of the cell surface arising between the stereocilia lead to cytoplasmic vacuoles that concentrate the particulate matter. The limiting membrane of the stereocilia and of the canaliculi and vacuoles is covered by a layer of amorphous material. It is speculated that this may bind particles, molecules, and ions as does an ion exchange resin, and that it may, in this way, act as a carrier in the uptake and transport of substances by cells.
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  • 58
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    The @Anatomical Record 148 (1964), S. 507-516 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In this study the distribution of mast cells in the cephalic, middle, or caudal portions of the uterine horns did not differ. In cross-sections, however, mast cells were most numerous in the myometrium, intermediate in the tunica vasculare of the endometrium and least in the mucosa. In the endometrium, the mast cells were most numerous in the antimesometrial, least in the mesometrial and intermediate in the lateral quadrants. In the myometrium, however, the relative numbers of mast cells between the quadrants varied according to the day in the estrous cycle.On days 1 (the day after estrus), 2, 3, and 4, (the day of proestrus) of the estrous cycle, there were respectively 42.7, 21.8, 22.5 and 10.7 mast cells in the endometrium per 12 μ sections. The differences in means between groups was highly significant (P 〈 0.001). In mated females on 67, 79, 91, 103, 115, and 151 hours after ovulation, there were respectively 9.4, 8.4, 4.7, 5.6, 2.1, and 2.2 mast cells in the endometrium per 12 μ cross-section. The differences in the means were not significant.The mean number of mast cells per 12 μ cross-sections of uteri of ovariectomized females was 20 ± 8. Subcutaneous injections of 0.3 gamma estrogen did not significantly alter the number of mast cells but 0.6 gamma depressed the mean count to 11 ± 7.It appeared from these studies that the uterine mast cell numbers were related to the cyclic phenomena of estrous, but that the numerical relationship to the time of nidation was not clear.
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  • 59
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    The @Anatomical Record 148 (1964), S. 552-552 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 60
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: An analysis was made on 140 adult chickens of the relationship between visual estimation of the degree of encroachment of the lumen of the vessel by plaques and such morphometric variables as weight, length, circumference, thickness, density, and combinations thereof of the thoracic and abdominal segments of the aorta. Aortic weight and thickness functions were found to be significantly correlated to scores, accounting in the two highest cases (thickness and weight/area of the abdominal segment, body weight held constant) for 46% (r = 0.68) and 42% (r = 0.65) respectively, of the variability in score. Correlations were considerably lower in the thoracic segment, the highest being r = 0.36 for weight/circumference. The scoring thoracic segment, the highest being r = 0.36 for weight/circumference. The scoring system thus has a basis in measurable physical changes in the wall of the blood vessel, but scoring apparently evaluates considerably more than was measured by the morphometric variables. The morphometric variables would probably serve best as means of comparing different scoring systems and as objective supplements to scoring. The procedure of choice would appear to be weight/area with body weight held constant (i.e.  -  partial correlation and/or covariance analysis).
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  • 61
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    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In the literature the nutrient artery to the diaphysis of the canine femur has been described as arising from the medial circumflex femoral artery which is a branch of the deep femoral artery. However in 19% to 100 canine hind extremities dissected after injection with colored media, the femoral nutrient artery arose from a large muscular branch (the proximal posterior femoral) of the superficial femoral artery. In 17% of 42 dogs one femur only was supplied by this variant. In three additional femurs other variations occurred.
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  • 62
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Following surgical removal of one eye, rats were permitted to survive for three days, one, two and four months, and before killing them they were injected with 2 mc of leucine-H3 intraperitoneally. The utilization of this radiochemical was investigated in the brain autoradiographically. In all groups of animals the uptake of radioleucine, as determined by microdensitometry, was significantly higher in the “degenerated” optic nerve and tract than in their “normal” counterparts, with the relative difference increasing with longer postoperative survival within the periods tested. This progressive net increase in the utilization of leucine-H3 was associated with an absolute increase in the number of glia cells. Similar, but attenuated, density differences were also obtained with relatively large-aperture measurements over the stratum griseum of the superior colliculus in which the optic tract fibers terminate. In contrast, small-aperture measurements of grain density over single neurons in the lateral geniculate nucleus showed no difference in the utilization of leucine-H3 between the normal and subtotally deafferented sides. This suggests an absence of transneuronal changes in protein metabolism in the visual system of the rat as long as four months after unilateral enucleation.
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  • 63
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    The @Anatomical Record 148 (1964), S. 573-579 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Fixation of the thyroid gland with formaldehyde-ethanol-acetic acid retains a larger proportion of colloid constituents than aqueous formaldehyde.Comparative histochemistry has revealed a larger proportion of protein, arginine, cabohydrates and iodinated material.The heterogeneous staining pattern was not observed after aqueous formaldehyde fixation.The intracellular globules and the early iodinated fraction of the colloid were similarly stained.Intracellular globules were not observed in aqueous formaldehyde-fixed tissues.Only the more slowly labeled fraction of the colloid (large follicles), was stained by toluidine blue and also by bromphenol blue without mercury, indicative of basic proteins.
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  • 64
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    The @Anatomical Record 148 (1964), S. 553-559 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The pleural cupola is covered by a distinct dome-shaped suprapleural membrane (Sibson's fascia) formed by a condensation of endothoracic fascia and continuous at its periphery with the more diffuse, loose endothoracic connective tissue lying between the ribs and the parietal pleura. This does not agree with the classic description of Sibson's fascia. It forms a discreet cervicothoracic cloison which can be readily separated from the pleura and adjacent mediastinal structures. Attaching to the membrane are the vertebromembranous, transversomembranous, and costomembranous bands which are formed by prevertebral fascia. In addition, the last two suprapleural bands receive contributions from the fibrous remains of the scalenus minimus muscle. The muscle was found to be present on one or both sides in 30 out of 64 bodies (46.8%). The suprapleural membrane and bands can become hypertrophied and fibrous as a result of pathology in this cupola area of the lung. The bands have been implicated in certain clinical syndromes.
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  • 65
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    The @Anatomical Record 148 (1964), S. 561-571 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Wistar strain albino rats were injected with 1 cm3 of a 1% solution of trypan blue. Three types of dye were used: Matheson, Coleman and Bell, Chroma-Gesellschaft and a highly purified sample. The dyes were injected on days 6, 7, and 8 of gestation. Fetuses were excised from days 16 through 20, fixed, decalcified where necessary, embedded in paraffin, serially sectioned and stained. Newborn young were treated similarly. Chroma-Gesellaschaft trypan blue was without reproductive or teratogenic effect at the above doses. Increasing the dose did not increase the teratogenicity but did yield a decrease in litter size. Both Matheson, Coleman and Bell trypan blue and the purified sample were teratogenic. The most frequent neural defect observed was hydrocephalus. Serial sections of the newborn hydrocephalics showed an occluded or extremely tenotic aqueduct of Sylvius in 31 of 33 sectioned animals. The fetuses collected from days 18 through 20 also had occluded or stenotic aqueducts if hydrocephalic. Aqueductal stenosis or occlusion was present in 17-day-old fetuses, but hydrocephalic was not conclusively demonstrated at this age. Sixteen-day-old fetuses did not have aqueductal occlusion in any of those examined, but stenosis was evident. It is concluded that the defect predisposing to hydrocephalus in the young of trypan blue treated rats of this strain is aqueductal stenosis or occlusion.
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  • 66
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Testicular fragments from newborn, 4, 14, 24, 37-day old and mature rats were cultured using a modification of Trowell's method. Eagle's medium supplemented with amino acids, Na-pyruvate and 10% calf serum was employed. Tissue fragments were fixed at time intervals for histologic study. In cultures of fragments from newborn and four-day rats, gonocytes persisted and showed mitotic activity. In fragments from older but still immature animals, gonocyte-like cells occasionally undergoing mitosis, appeared in the germinal epithelium after the fourth day in culture. Spermatocytes survived for approximately four weeks. More rapid degeneration of the germinal elements beyond spermatogonia was observed in cultures of mature testes. During the first six days in culture, cells resembling gonocytes, some in mitosis, appeared in the tubules. The studies have shown that under the conditions employed, Sertoli cells and gonocyte-like could be maintained for at least four months in cultured fragments of testes from animals of various ages. In fragments from older animals, gonocyte-like cells appeared shortly after initiation of culture while the more mature germinal elements ultimately degenerated.
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  • 67
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    The @Anatomical Record 148 (1964), S. 605-609 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Follicular activity in the ovary of the pregnant hamster is divided into two periods. During the first eight days (corresponding to the duration of pseudopregnancy) an average of 11 follicles per ovary from 277 to 553 μ are present. From day 10 to 16 of pregnancy, the ovary contains 22 follicles ranging from 277 to 600 μ and larger. The day after parturition, atresia destroys all large multilayered and vesicular follicles.Hamsters injected with human chorionic gonadotropin on day 4 of pregnancy ovulated ten ova, whereas similary treated day 12 animals ovulated 35 eggs. No cyclic follicular activity corresponding to the length of the estrous cycle occurred during gestation. On the contrary, a constant increment of small follicles took place throughout pregnancy.
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  • 68
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    The @Anatomical Record 148 (1964), S. 591-597 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The morphology of the cecal mucosa and the topographic distribution of certain mucosal enzymes were compared in conventional and germfree mice to investigate the phenomenon of cecal enlargement observed in germfree animals. The cecal mucosa is predominantly non-villous in the conventional, but has a villous structure in the germfree mice. Alkaline phosphatase, in the conventional mice, is present in the striated border of a limited number of the epithelial cells lining the cecum; in the germfree mice almost all these epithelial cells show enzymatic activity. Acid phosphatase is more abundant in the epithelial cells and macrophages of the cecal mucosa of the conventional than of the germfree animals. Both groups show similar monoamine oxidase and reduced diphosphopyridine nucleotide diaphorase activity. The reduction of the villi, and the decrease in alkaline phosphatase activity in the conventional mice point to an involution of the mucosa as an absorptive organ. Barka ('63) has suggested that acid phosphatase may have a defensive function; its increase in the conventional animal would support this interpretation. The two oxidative enzymes studied apparently are not influenced by the intestinal flora.
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  • 69
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    The @Anatomical Record 148 (1964), S. 599-603 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: With the object of investigating the so-called “feed-back” mechanism whereby hormones from the various endocrine glands presumably influence the hypothalamus in its regulation of the hypophyseal tropic hormones, the effect of hypophysectomy, ovariectomy, thyroidectomy, adrenalectomy and adrenal medullectomy on the nucleolar size of neurons in 16 hypothalamic nuclei was studied. A total of forty-five female albino rats was used. The nucleoli were measured under oil by means of a Cooke AEI image splitting eyepiece. For every rat 50 nucleoli in each of the 16 hypothalamic nuclei was measured, a total of 36,000 measurements. Hypophysectomy was found to affect all of the nuclei either after a short period (5 days) or after 60 days. Ovariectomy (20 days) caused nucleolar size changes in six nuclei, thyroidectomy (30 days) in eight, adrenalectomy (14 days) in all of the nuclei and adrenal medullectomy (30 days) in all of the nuclei. The results indicate that the absence of the various hormones does affect the activity of hypothalamic neurons as determined by nucleolar size changes. The use of the present methods also appears to “localize” centers for specific activities in the hypothalamus in some instances (e.g. ovariectomy) but not in others (e.g. adrenalectomy).
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  • 70
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The gross arterial blood supply to the trachea, primary bronchi, and esophagus of six normal domestic rabbits has been studied by the use of injection techniques followed by careful in situ dissections. Several patterns are described with more variation being apparent on the left side.
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  • 71
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    The @Anatomical Record 148 (1964), S. 631-632 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A plastic sealing compound for museum jars is described. It has the consistancy of toothpaste and is applied in a similar manner directly to the museum jar from a tube. No catalyst or mixing is required. Moisture in the air cures the plastic in 12-24 hours. After the extruded “rope” is applied, the lid is placed on the jar and the jar set aside for the cure. After cure any excess can be trimmed with a scalpel.
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  • 72
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    The @Anatomical Record 149 (1964) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 73
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Recent Primate research projejcts utilizing the squirrel monkey (Saimiri sciureus) established the need for basic biological data concerning this animal. Included in this present report are discussions of laboratory maintenance, dietary requirements, and antihelminthic thearpy. Original data on birth weight (90-100 gm) and the gestation period (167 ± 2 days) are recorded. The weight distribution of a colony of adult animals maintained in captivity for a period of three years is included. Fresh organ weights from ten animals obtained at necropsy were recorded for brain, pituitary, heart, lungs, spleen, liver, pancreas, kidney, adrenals, and gonads. Body weight, body length, and the length of the esophagus, stomach, duodenum, small intestine, cecum, and colon were recorded. Determination of hematologic values included erythrocyte and leukocyte counts, hemoglobin and hematocrit determination and differential count of white blood cells. Various blood chemistry values are included. Data on heart rate, respiratory rate and body temperature of animals restrained for a 24 hour period are tabulated. Environmental stress and neuroanatomical studies using the squirrel monkey are reviewed.
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  • 74
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The course of development of parabiotic anastomosis was followed with respect to time in Holtzman (Sprague-Dawley) parabionts. Comparison of non-irradiated pairs was made to pairs in which one of the partners had received 800 r. The development of the anastomosis was studied by determining the per cent transfer of CR51 labeled erythrocytes (which represented a cellular element) and radio-iodinated serum albumin (which represented a molecular element) from one partner to the other. Erythrocytes were found in the non-injected animal in small numbers at 22 hours after pairing; at 47 hours the rate of transfer became much more rapid. RISA was detected in the non-injected partner as early as five hours after pairing and accumulated steadily thereafter. Irradiation had no effect on the course of development of the parabiotic anastomosis as evidenced by similarity of accumulation rates of Cr51 labeled erythrocytes and RISA when compared to the non-irradiated pairs.
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  • 75
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    The @Anatomical Record 149 (1964), S. 23-35 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A light and electron microscopic study of the early changes which occur in cadmium necrosis of the testis of the mouse was made in an effort to identify the site of action of cadmium. Mice were given a single, intraperitoneal injection of 1% CdCl2 at a dosage of 0.1 ml/10 g body weight and then the testes were fixed for light and electron microscopy at various hourly intervals. The earliest changes which were appreciated by light microscopy consisted of an edema of the intertubular spaces, congestion of blood vessels, and an increased amount of granular precipitate in the connective tissue spaces. By electron microscopy the earlies changes were observed in the endothelium of the testicular vascular bed and consisted of a striking and rapid increase in the prevalence of pinocytotic vesticles suggesting an increased interchanges of fluid between the blood and extravascular spaces. All of these changes preceded any appreciable alteration in the cells of the seminal epithelium. The fact that the earliest alterations are observed in blood vessels suggests that the site of action of cadmium in the production of testicular necrosis is upon the endothelium of the vascular bed.A comparative series of animals (frog, pigeon, rooster, armadillo, opossum) was also investigated as to their susceptibility to the toxic effects of cadmium. the results from these species, and other species reported by previous investigators, suggest the generality that cadmium necrosis is a phenomenon common to species possessing scrotal testes and absent from those possessing abdominal testes. The opossum is an exception to this generality. These findings are discussed in relation to the blood supply of the testis.
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  • 76
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: First, using the methods of H3-thymidine autoradiography and counting mitotic index, cytokinetics of the matrix cells were studied in the telencephalon of normal mouse embryos at ten-days-postconcetpion, and various kinetic constants of the matrix cells were determined: Generation time, five hours 20 minutes; mitotic duration, 24 minutes; presynthetic resting time, two hours 36 minutes-one hour 36 minutes; DNA synthetic time, one hour 20 minutes; and post synthetic resting time, one-two hours. Based on this information, effects of two teratogenetic agents, x-rays and thio-TEPA, on the cellular proliferation were analyzed. By x-ray irradiation (200 r) only proliferating matrix cells are damaged in the neural tube, but not neuroblasts. The radiation induces a temporary block of the flow of the matrix cells through the cell cycle at the late t2 period so that the mitotic and DNA synthetic cells subsequently decrease in number. Some of the matrix cells that are captured at t2 period fail to tolerate the block, degenerate and are eliminated from the matrix layer. On the other hand, thio-TEPA, which was proved non teratogenetic to the C. N. S. in this experimental condition, causes a slight prologation of t2 duration, but does not significantly influence the proliferative process in the neural tube.
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  • 77
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    The @Anatomical Record 149 (1964), S. 49-55 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A purified diet lacking folic acid and containing 20 mg% of the antimetabolite, 9-methyl pteroylglutamic (folic) acid was fed to female Long-Evans rats during days eight and nine of pregnancy. Embryos were removed at autopsy on the tenth day of gestation for study and comparison with embryos from normal control pregnancies.Analysis of mitotic counts revealed that 18.6% of the cells in control embryos were in mitosis in contrast to only 5.7% in PGA-deficient embryos. A disproportionate reduction in anaphase and telophase stages was observed in conjunction with an increased percentage of cell at metaphase. Concomitantly with these mitotic changes a marked reduction in histochemically demonstrable RNA and in numbers of ribosomes as revealed by electron microscopy was observed.
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  • 78
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    The @Anatomical Record 149 (1964), S. 397-404 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A 79 year-old European female cadaver presented the usual features of second stage arrested mid-gut rotation accompanied by unusual mesenteric attachments and pancreatico-duodenal relationships.The mesentery, whose root extended from the lower pole of the right kidney diagonally across the posterior abdominal wall to end just medial to the left sacroiliac joint, enclosed most of the small bowel and the proximal large bowel. The unusually short duodenum began 2.5 cm to the left of the mid-line and described a 13 cm U loop with an upward concavity in which rested the pancreas; this loop and the related pancreas were enclosed in a persistent, transversely placed mesoduodenum. The common bile duct crossed the anterior surface of the pancreas to open at the greater duodenal papilla 2.5 cm from the pylorus. the main pancreatic duct lay much closer to the anterior than to the posterior aspect of the gland. The lesser duodenal papilla was situated on the posterior wall of the duodenum. The hepatic artery arose in common with the superior mesenteric artery and encircled the pancreas. The pancreatico-duodenal vessels were predominantly distributed upon the posterior aspect of the pancreas and duodenum.It appears that in this specimen the anterior and posterior aspects of the duodenum are transposed, the reversal of surfaces also involving the pancreas. Causative factors are discussed with reference to the literature.
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  • 79
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A number of histologic and histochemical techniques have been used to study 42 human fetal thyroids from fresh specimens ranging in crown-rump length from 22 to 201 mm. Three periods of differentiation (colloid production) were defined. The first or precolloid stage was found in fetuses of 22 to 65 mm and consisted of strands of compact epithelial cells separated by loose connective tissue which contained only a few vessels. The early colloid production period from 65 to 80 mm was characterized by the appearance of small accumulations of colloid in the center of the follicles. The blood vessels between follicles increased during this period. In the last period during maturation of the colloid cavities, the spaces between the epithelium were more reduced and almost completely filled with blood vessels. No change in the average cell height was found during differentiation.With differentiation, the nuclei of epithelium became less compact and RNAase-removable cytoplasmic material increased. Also of interest was the marked decrease in glycogen at the time of colloid production.The staining characteristics of the early colloid showed little change during the period studied. The colloid was stained by the following reagents: periodic-acid Schiff, mercury organge, toluidine, ninhydrin-Schiff, Millon's and Sakaguchi's. The larger colloid spaces took slightly more toluidine stain than the smaller ones.The enzyme reaction for alkaline phosphatase was found only in the vascular system, and acid phosphatase was found in the cytoplasm of epithelium and, especially in the differentiated specimens, it was concentrated at the apex of the cell. Lactic and succinic dehydrogenase activity did not seem to change with maturation and was located in the cytoplasm around the nucleus and toward the apex of the cell.Thin rays of colloid-like material were observed to radiate out between cells from early colloid cavities. Based on unpublished electron microscopic data, organ cultures of human thyroid and observations from the developing chick, these spaces probably represent intercellular dilatations which have been filled with colloid from the central cavity. These spaces may be a secondary or safety mechanism which allows the circumference of the follicle to increase in size.
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  • 80
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    The @Anatomical Record 150 (1964) 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
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  • 81
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    The @Anatomical Record 150 (1964), S. 11-24 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The topography of nasal glands in rats, guinea-pigs, rabbits, cats, and monkeys was studied in osmium tetroxide and PAS-stained whole mounts and ordinary sections. In rats Bowman's glands in the olfactory region were arranged in rows between the branches of the olfactory nerve. Mucous acini were only found on the rat septum in connection with Jacobson's organ, and serous acini were found on the septum posteriorly in the respiratory region, and on the lateral wall of the nasal cavity around the maxillary sinus ostium. No mixed glands were present. All the serous glands discharged their secretion through long excretory ducts into the ostium internum of the vestibule of the nose. In this area rats had 15-20 duct openings on each side. On the basis of considerations regarding airstream and pressure in the vestibule, the hypothesis is advanced that the openings act as small nozzles humidifying the inspired air by their atomized secretion. Since no serous or mucous glands in the rat open on the surface in the nasal cavity proper, it is concluded that the surface mucous sheet is derived exclusively from the goblet cells and Bowman's glands. In the other mammals the opening of the serous glands showed a similar pattern.
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  • 82
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Four stocks (C, C-57 Bl, DBA and Swiss albino) of mice were fed a high-fat (28%), low-protein (8%), hypolipotropic diet for 3-480 days. Lipotropic activities of supplements of betaine and carnitine were evaluated. There were no strain-limited hepatic responses to the diet or to the action of the lipotropes. Without lipotropic supplements, parenchymal liposis (sudanophilia of frozen sections) was progressively incremental in all lobular zones for approximately 90 days. Subsquently, lobular liposis decreased and the remaining fat was concentrated in the middle zone within cords of fat-laden cells radiating in a stellate pattern. With choline supplemention, liposis was limited to small amounts of fat within cells that composed the stellate pattern. Betaine displayed a level of lipotropic activity approximating one-half to three-fourths that of choline. The lipotropic activity of carnitine was marginal and inconsistent. The combination of betaine and carnitine demonstrated some synergistic action. No parenchymal hyperplasia was observed. The intralobular reticulum increased in some livers, primarily around the central and intercalated veins, but no lobular distortion resulted.
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  • 83
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    The @Anatomical Record 149 (1964), S. 707-720 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: This study was based upon a dissection of the pelvic fasciae and associated structures of one hundred and three adult pelves as well as those of three full term fetuses. The perineal fasciae and their neural and vascular relationships were studied in an additional 55 specimens.The uterovaginal fascia, as stated by others, is a well-defined structure. One is usually able, on the basis of a fascial cleft, to distinguish readily between the fascial sheath of rectum proper and the deeper layer of subperitoneal fascia, called by some the presacral fascia. The latter is described, including the relationship of the pelvic autonomics thereto. The relationship of the vesical branches of the pelvic plexus and of the venous plexuses to the terminal ureter are also described.We were able to confirm the presence of a superficial and a deep perineal fascia; the latter forms the inferior boundary of the superficial perineal space proper, as described by others. The relationship of particular nerves (and vessels) to the fascial planes of the perineum follows a definite pattern even when variation from the normal is present.
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  • 84
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Alterations in size and structure of submandibular and retrolingual glands of the rat produced by unilateral sectioning of the chorda tympani, or the lingual nerve, or the glandular branch which leaves the lingual and innervates both glands, are described. The glands were studied 1, 2, 4, 8, 12 and 16 days after nerve section.The weight of the glands increased the first day after nerve section and decreased markedly from then on, reaching 40 to 70% of the initial weight after 16 days. In the glands where the chorda tympani or the lingual nerve were sectioned the increase in weight was attributed to the accumulation of secretion in the acinous cells. After that, a progressive atrophy developed, being more severe in the acini than in the tubes. In the cases where the glandular nerve was sectioned a wide necrosis probably of vascular origin was produced, followed by parenchymatous regeneration.In both cases 16 days after nerve section glands were small, fibrous and with little parenchyma.The role of the parasympathetic nerves in controlling the normal structure of submandibulars and retrolinguals is discussed.
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  • 85
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    The @Anatomical Record 150 (1964), S. 317-318 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: This article describes a rapid exposure of the facial nerve by splitting the parotid gland along the faciovenous plane originally described by Patey and Ranger ('57).Scissors are thrust deep into the gland along the venous plane, and then opened to expose the facial nerve. This has been done in approximately 30 dissecting room subjects.
    Additional Material: 2 Ill.
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  • 86
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The effects of hyper- and hypothyroidism on fetal development and on the postnatal maturation of the central nervous system was studied in the rat. Our observations indicated that the development of the rat fetus, as measured by birthweight and skeletal maturation of the newborn animal is not markedly influenced by presence or absence of thyroid hormone during the prenatal stage.Availability of thyroid hormone is a more critical factor with respect to maturation of the nervous system taking place in the postnatal animal.Delay in cerebellar maturation and delay in increase in dry weight of cerebrum and cerebellum were noted in hypothyroid rats. A transitory acceleration of oxygen consumption of these structures during their maturation was also noted in hyperthyroid litters.A more permanent suppression of learning behavior and of the thermoregulating mechanism was observed in young hypothyroid rats deprived of thyroid hormone since birth.It is concluded that requirements for thyroid hormone during development of the rat are limited to a critical period coinciding with the first two to three weeks of postnatal age.
    Additional Material: 4 Ill.
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  • 87
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 150 (1964), S. 195-207 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Cholinesterase (ChE) distributions in the epithelial and smooth muscle cells and in the peripheral nervous plexus of the reproductive ducts of the male rat are dependent on male sex hormones. Castration results in establishment of a low maintenance level of apical enzyme activity in the epithelial cells; smooth muscles and the nerve plexus of the vas deferens and cauda epididymidis also show reduced enzyme reactions. Testosterone treatment restores the normal enzyme relations in the epithelium and smooth muscles. Estradiol is partially effective, but reaction intensities do not attain normal distrbutions and proportions. Reductions in relative numbers of ChE positive nerve plexus fibers and their enzyme reactivity, and recession to outer muscle layers occur in castrates, but better recoveries follow after testosterone than after estradiol treatments. The results are interpreted to be in agreement with other data relating to smooth muscle behavior and its neural and hormonal regulation. Epithelial cell differentiation is complete in testosterone treated castrates, but is incomplete in estradiol treated cases, although ChE synthesis and duct growth occurs in the latter.
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  • 88
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: A comparative histological and histochemical study of the gastric mucosa was done with the frog, mouse, rat, hamster, guinea pig, rabbit, cat, dog and man. Enzymatic histochemical studies were done to demonstrate acid phosphatase (PbS and azo-dye methods), thiamine pyrophosphatase (TPP-ase) and NADH2 tetrazolium reductase activity. Cytoplasmic organelles were stained in some cases by three of the above methods i.e. acid phosphatase (PbS) activity marked the lysosomes, TPP-ase activity marked the Golgi apparatus and NADH2 tetrazolium reductase activity marked the mitochondria. The acid phosphatase activity of the four major cell types was markedly different in the various species. The activity shown by both methods in individuals of a given species coincided well except in the rabbit and the dog. TPP-ase activity demonstrated the Golgi region in the surface cells of all species except the guinea pig and the frog. The Golgi zones of zymogen cells showed strong activity only in the cat, while the parietal cell Golgi was not demonstrated in any of the species. NADH2 tetrazolium reductase activity in the parietal cells was strong in all animals except the mouse and the rat where staining was faint. The relationship between the lysosomes and the Golgi apparatus, as demonstrated histochemically in the gastric cells of the nine species, is discussed. The functional significance of these different enzymatic patterns has yet to be determined.
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  • 89
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Adult rats, given intracardiac injections of strychnine (2.5 mg/kg), were allowed to convulse for periods of 5 or 35 minutes after which they were perfused with osmium tetroxide using a variation of Palay's method.Light and electron microscopic examinations revealed no discernible changes in the size of the soma or appearance of the nuclei or nucleoli of the neurons of the ventral horn. However, light microscopic studies showed that clustering of the basophilic content was not as well defined as in the control cells. The most conspicuous feature of the treated material was the presence of a peripheral network of clear spaces in the cytoplasm of many of the large neurons.An electron microscopic investigation showed that many neurons exhibited obvious and consistent cytoplasmic differences from control cells. These differences consisted of dilated endoplasmic spaces approximately 0.4 μ in diameter dispersed throughout the cytoplasm and devoid of material of appreciable density. The Golgi complex was more conspicuous and vesicles surrounding the complex appeared to be more numerous following the convulsive periods. These cytological changes were more extensive and prominent after 35 minutes than after five minutes. Mitochondria were comparable in appearance to those of control cells and vesicles of the axosomatic and axodendritic endings did not seem to differ structurally or numerically from those of control tissues.
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  • 90
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Cattle were injected with PMS, bred and slaughtered 3, 30, 45, 60 and 90 days after ovulation and the genital tracts dissected. From 30 to 90 days of pregnancy the percentage increase in the weight of single embryos was 85 times as much as the increase in crown-rump length. The volume of amniotic fluid increased 580 times in the second month of pregnancy and increased twice during the third month of pregnancy. The allantochorion did not lengthen between 60 and 90 days of pregnancy. At 30 days of pregnancy there was no significant difference in the crown-rump length or the weight of embryos of singles, twins, triplets, quadruplets or quintuplets. The volume of placental fluid per embryo was higher in singles than in twins and triplets; the volume of placental fluids per embryo decreased further in quadruplets and quintuplets. The weight of the placental membranes per embryo was heavier in singles than in twins, triplets and quadruplets; the weight of membranes was markedly decreased in quintuplets. The effects of overcrowding in utero on the conceptus was more pronounced at 60 days than at 30 days and in quintuplets than in triplets and quadruplets. Anastomosis of vascular supply of allantochorions occurred as early as 30 days of pregnancy.
    Additional Material: 9 Ill.
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  • 91
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 150 (1964), S. 343-348 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Data were collected from a colony of 49 male and 55 female two-year-old Mongolian gerbils, Meriones unguiculatus (Milne-Edwards, 1867). This report gives tables which present data regarding linear measurements of body and organs and absolute and relative organ-weight data. The means, standard deviations, ranges, and coefficients of variation were summarized in the tables. Grossly observed pathological organs were omitted from the study. The tables give information about this species which could be helpful in future laboratory investigations where the body-and organ-weight ranges, variability and linear measurements of this species may be of practical value.
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  • 92
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The organized cartilaginous fibrous system which appears during growth of the fracture callus in traumatized femora was investigated in mice of five, 52 and 78 weeks of age. Histological preparations were stained with toluidine blue O and observed under polarized light using a first order red retardation plate.Development and organization of the cartilaginous fibrous system was similar in animals of all age groups studied, however, its time of appearance was dependent upon the time of appearance of cartilage cells and in association with these cells. Alignment of cartilage cells followed very closely after appearance of the fibrous system. Initial orientation of the fibrous system was almost perpendicular to the bone surface. As the system became more extensive the slope of fiber direction became less acute, pointing towards the fractured end of the shaft. Orientation of the fibrous system is believed to be a consequence of the forces set up during growth of the fracture callus, e. g., the force of the growing cell mass due to postfracture, active cell proliferation of the osteogenic layer of the periosteum and hypertrophy of cartilage cells and the tension placed on the fibrous layer of the periosteum in response to the events taking place below this tissue layer. The importance of the cartilaginous fibrous system is believed to lie in the early temporary support of the fracture fragments and the proper alignment of the cellular elements of the fracture, necessary for proper architectural reconstruction. Formation of the cartilaginous fibrous system was independent of the existing periosteal fibrous system.
    Additional Material: 4 Ill.
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  • 93
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Studies of the ultrastructure of the seminiferous tubule of the Swiss mouse have shown the external limiting membrane to consist of internal and external lamellae enclosing a single layer of flattened cells. Both lamellae contain fibers, probably collagenous, running parallel to the long axis of the tubule. Superficially, a layer of connective tissue cells covers the external lamella. The nucleus of the Sertoli cell is typified by irregularity of size and shape, electron density of the nuclear membrane, and characteristic nucleolus. The cytoplasm contains mitochondria with vesicular cristae, and irregular dense bodies of possible secretory origin. Cytoplasmic processes extend between the germinal cells and in certain areas their surfaces are marked by periodic accumulations of fine granules which present a picture suggestive of desmosomes.Two types of spermatogonia have been noted. One possesses a large spherical nucleus containing finely granular nucleoplasm and scanty cytoplasm. The second is characterized by an ovoidal nucleus containing numerous chromatin clumps and scattered nucleolar fragments. Primary spermatocytes exhibit the intercellular bridges and synaptinemal complexes characteristic of these cells. The spherical nuclei contain densely packed fine granules. The nuclei of secondary spermatocytes often exhibit centrally located clumps of chromatin material. Mitochondria appear vacuolated at low magnifications but high magnification micrographs show them to contain finely membranous cristae.
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  • 94
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The pattern of growth of bone and dentin was studied in serial decalcified sections by the use of lead markings. The experimental animals (monkeys and rabbits) received repeated intravenous injections of 4 mg lead acetate/kg body weight. The tissues were decalcified in 1% HCl through which H2S was constantly bubbled. Serial frozen sections were cut at 15-20 μ embedded in 10% gelatin and mounted in polyvinyl pyrollidone. They were placed in a 0.1% solution of gold chloride for ten minutes and then immersed for the same length of time in a 5% solution of sodium bisulphate in order to tone the background tissues. The sections were transferred to distilled water until the tissues became pink. When the desired toning was obtained they were fixed in 5% sodium thiosulphate. The examination of the sections obtained by this method confirmed the data obtained by other vital marking methods. However, much finer detail could be observed due to the sharpness of the lines and the use of relatively thin decalcified sections.
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  • 95
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 148 (1964), S. 1-14 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: In the testes of man and some other mammals a structure is formed during reproductive age, designated a “receptacle”. This structure which is not present during infancy represents the first communication of the seminiferous tubules to an extragonadal organ the rete “organ,” the receptacles received the mature spermatozoa which later are transported to the mesonephric excretory duct through the rete tubules. The receptacles are the distal end of the rete tubules and are considered as coelomic funnels.The epithelium of the receptacles, the tubuli recti and rete tubules is identical in infantile and mature testes and of a different type than the epithelium of the seminiferous tubules.The receptacle consists of a distal dilatation of the tubuli recti in which the seminiferous tubule invaginates following the ruptures of their walls. Identical receptacles are present in man, horse (Equus caballus), armadillo (Dasypus novemcinctus mexicanus), white-tailed deer (Odocoileus virginianus), dog (Canis familiaris), cat (Felix domesticus), hamster (mesocricetus auratus) and woodhuck (Marmota monax). In the mule (sterile offspring of a mare and a jackass) the receptacles lack communications.The presence of mature spermatozoa is believed to be the proper stimulus for the formation of the receptacles which established the communications between the seminiferous tubules and the rete tubules.The receptacles, tubuli recti and rete testis are part of an organ which accomplished the connection of the gonad to its mesonephric excretory system.
    Additional Material: 17 Ill.
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  • 96
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Thymus of guinea pigs and C3H mice was fixed in 1% osmium tetroxide, embedded in Araldite or Maraglas, and studied under the electron microscope.Hassall's corpuscles showing the typical concentric, lamellated pattern are observed. Reticular cells form layers around central elements of variable appearance. One or more reticular cells or cystic structures often constitute the centers of corpuscles. Nuclear degeneration, swollen cytoplasm, and intracellular fibrils are characteristic findings. Desmosomes may be quite numerous and may cover a large portion of a cell's surface. Intracellular fibrils are particularly dense at membranous sites and often are apparently unrelated to desmosomes. Reticular cells at the periphery of thymic corpuscles may be contiguous with cells of the cytoreticulum. Many reticular cells contain organelles generally associated with protein synthesis or active transport.Intercellular and intracellular cysts are regularly seen and are frequently related to thymic corpuscles. Some cysts may be manifestations of cell synthesis and storage.The epithelial nature of thymic corpuscles and cysts is evident. Thymic corpuscles may arise by localized collapse of the cytoreticulum.
    Additional Material: 14 Ill.
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  • 97
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The perineal pigment spot of the C57 Black mouse was examined macro- and microscopically in animals ranging in age from 14 days post-fertilization to 28 days post-parturition. Dendritic pigment-containing cells first become evident in the dermis of the area on the sixteenth day post-fertilization. Throughout later stages of development, these pigmented cells continue to be restricted to the dermis of this area. Since the dopa treatment reveals the presence of a melanin synthesizing system within these cells, they are true melanocytes which have become restricted to this layer of the integument.Histological examination reveals a population of melanocytes in the epidermis and/or hair follicles also. These are rarely found over the center of the area but are seen in increasing numbers laterally from the ventral midline. In contrast, dermal melanocytes are heavily concentrated near the ventral midline but decrease in numbers laterally. There are, therefore, two opposing but complementary gradients of melanocytes in the integument of the pigment spot. This suggests the possibility that a precocious differentiation of the basement membrane in this area during embryonic development inhibits the passage of melanoblasts into the epidermis thereby causing them to be restricted to the dermis.
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  • 98
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 148 (1964), S. 129-137 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Congenital malformations of the hamster eye, consisting of microphthalmia and anophthalmia have been noted consistently in the offspring of pregnant hamsters treated with intravenous injections of colchicine, Vinacaleukoblastine (VLB) and Vincristine (VCR) on the eighth day of gestation. In an attempt to compare the mitotic-arresting activity of these three compounds on the lens and retina of the fetal hamster eye, various concentrations of the drugs were injected into pregnant hamsters on the fourteenth day of gestation and the fetuses recovered after three hours. Mitotic counts were done on comparable sections of lens and retinas of the fetuses. Colchicine has the most marked mitosis-inhibiting activity of these three drugs. The most effective mitosis-inhibiting dosage of colchicine also correlates with its most effective teratogenic dose. VLB and VCR do not inhibit mitosis in the fetal hamster eye as markedly as colchicine and their most effective mitosis-inhibiting dosages are equal to or above levels which cause a 95-100% embryonic mortality. It is possible that some common biological mechanism other than inhibition of mitosis may be responsible for the similar teratogenic activity of these compounds. The natural resistance of the golden hamster to colchicine does not appear to be manifest in the developing embryos in utero.
    Additional Material: 12 Ill.
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  • 99
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    The @Anatomical Record 148 (1964), S. 139-147 
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: Body weight and length, weights of 14 organs and 15 linear measurements are presented from 97 Amblystoma tigrinum melanosticum before metamorphosis and 57 specimens after metamorphosis. These data are compared with similar measurements (previously published) on adult salamanders.Body weight and weights of the digestive tube and its subdivisions, liver, pancreas, spleen, eyeballs and brain are heavier in the larvae. The body weight decreases more than many of the organs and hence the percentage weights of the heart, lungs, liver, spleen, kidneys, gonads, eyeballs and brain are larger, relatively, in the post-metamorphosis salamanders.Since body length is not significantly changed, the percentage lengths are much the same. Length of the digestive tube and its parts, jaw width and the width of the body at pectoral, belly and pelvic regions are all longer in the larvae. The limbs are the only percentage lengths greater in the post-metamorphosis salamanders.All of the weights and all of the linear measurements are significantly correlated with body weight or length, respectively.Four organs show increases in percentage weights at all three periods: gonads, lungs, liver and spleen. Two others have an increase in post-metamorphosis: heart and kidneys. The digestive tube and its parts and the pancreas have a relative decrease at the end of metamorphosis. The eyeballs are relatively largest in the post-metamorphosis, and smallest in the adults.
    Additional Material: 4 Tab.
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  • 100
    ISSN: 0003-276X
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine
    Notes: The weights of 75 human fetal thyroids were analyzed in relation to crown-rump length, foot length, weight, and estimated gestation age. The ratio of thyroid weight to body weight was lower in the smaller fetuses and gradually increased until the fetus was 70-90 mm in crown-rump length when the ratio attained a value close to that found in the newborn and adult. This period of development when the relative weight of the thyroid becomes constant coincides with the time of appearance of colloid and the onset of ability to concentrate iodine.A comparison of estimated age of fetuses in the Danish material and the formalin-fixed fetuses from the Carnegie Collection shows the Danish fetuses under 40 mm in crown-rump length to be four to six days older than the average given by Streeter. Streeter may have made his average too low and probably the relative ages of the two groups are comparable.
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