Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles: DFG German National Licenses  (24)
  • 2000-2004  (15)
  • 1970-1974  (9)
  • 1
    Electronic Resource
    Electronic Resource
    Ion transport through unsaturated soils: field experiments and regional simulations (2002)
    Oxford, UK : Blackwell Science Ltd
    European journal of soil science 53 (2002), S. 0 
    Details
    ISSN: 1365-2389
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: This paper describes the movement of anions and cations through soils at the regional scale using block-scale and regional simulations of one-dimensional ion transport through cultivated soils. The simulations were based on field experiments in a region of about 10 km2 in Lower Saxony, Germany. Transport was modelled with the convection–dispersion equation, and the cation exchange was described using the Gapon equation. We evaluated the spatial variation of cation exchange parameters, obtained estimates valid at the block scale, and simulated the one-dimensional transport of anions and cations. The movement of anions and cations was simulated over blocks using effective transport parameters calculated from local transport parameters. The approach led to a good agreement between measured and predicted concentrations of Br–, Na+, K+, Ca2+ and Mg2+ on four different 1 ha blocks. However, the mean concentrations of K+ in the soil solution in the uppermost horizons could not be described satisfactorily by the model. For the regional simulations, transport and exchange parameters were estimated by block kriging. All variograms of the exchange parameters were spatially structured with correlation lengths varying from 100 m to 300 m. Results of the regional simulations imply that Cl– and K+ were transported substantially deeper in the southern part than in the northern part of the area. The transport depth of the ions strongly depended on the pore water velocities. The simulation of solute transport to the water table showed the influence of the depth of water table on the estimated travel times, superimposing the influence of the transport parameters in the region. The results of the regional simulations also emphasize the importance of careful fertilization, especially in regions with shallow water tables such as in the north of the area.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2389.2002.00422.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    EVIDENCE FOR SEPARATE SYSTEMS FOR THE TRANSPORT OF NEUTRAL AND BASIC AMINO ACIDS ACROSS THE BLOOD-BRAIN BARRIER (1971)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 18 (1971), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract— The effects of high circulating concentrations of several amino acids on the free amino acids of rat brain were measured, to see whether or not the results followed any consistent pattern. High circulating concentrations of large, neutral amino acids (phenylalanine, valine or isoleucine) caused significantly decreased values only of other large, neutral amino acids in the brains. High circulating concentrations of the basic amino acids lysine or arginine caused significantly decreased values only of each other. The data suggest that there are separate systems for the transport of neutral and basic amino acids across the blood-brain barrier. The effects of valine and lysine on the uptake by brain and the con-vulsant action of allylglycine (a neutral amino acid) were consistent with the concept of separate systems for the transport of amino acids across the blood-brain barrier. Valine inhibited the uptake by brain and the convulsant action of allylglycine in mice, but lysine did not. The data suggest that allylglycine and valine are transported into the brain by a common mechanism that does not transport lysine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1971.tb11991.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    THE SUBCELLULAR LOCATION OF THE HIGHER ACETYLCHOLINE CONTENT IN RAT BRAIN FOUND AFTER KILLING BY THE NEAR-FREEZING METHOD AS COMPARED WITH DECAPITATION (1974)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 23 (1974), S. 0 
    Details
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract— We have confirmed the finding of Takahashi & Aprison (J. Neurochem.11, 887-898, 1964) that more acetylcholine is found in brains of rats killed by near-freezing compared to decapitation. The radioenzymic assays for acetylcholine and choline of Shea & Aprison (Analyt. Biochem.56, 165-177, 1973) and Goldberg & McCaman (J- Neurochem.20, 1 8, 1973) were used to measure both compounds and gave very similar results. The larger amount of ACh was observed both in powders of frozen rat brain and in homogenates prepared from animals killed by near-freezing. When subcellular fractionation of the homogenates was done in the presence of eserine, the larger amount of ACh was found in the soluble fraction (S2). These results indicated that with the near-freezing method, an extra amount of ACh is preserved in a form that is originally protected from acetylcholinesterase but that becomes esterase-sensitive on fractionation since no differences were observed in P1. P2 or S2 fractions when no eserine was present. The amounts of choline in homogenates and subcellular fractions were also measured after both methods of killing. Differences in the method of killing and postmortem changes which affect the choline values obtained are described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1471-4159.1974.tb12221.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    The utility of cytokeratin subsets in distinguishing Barrett's-related oesophageal adenocarcinoma from gastric adenocarcinoma (2001)
    Oxford, UK : Blackwell Science Ltd
    Histopathology 38 (2001), S. 0 
    Details
    ISSN: 1365-2559
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Aims: Accurate tumour classification is critical for meaningful epidemiological studies in the assessment of cancer incidence rates and trends. Differentiating primary gastric carcinoma from oesophageal carcinoma can be difficult, especially when tumours are large and involve both the oesophagus and stomach. Furthermore, adenocarcinomas of both organs typically are of intestinal histological type and arise in a background of intestinal metaplasia. Consequently, histological markers that reliably distinguish Barrett's-related oesophageal adenocarcinoma from gastric adenocarcinoma would be useful. Cytokeratins (CK)7 and 20 are cytoplasmic structural proteins with restricted expression that help to determine the origin of many epithelial tumours including those of the gastrointestinal tract. The aim of this study was to determine the utility of co-ordinate CK7 and 20 expression in the distinction of Barrett's-related oesophageal adenocarcinoma from gastric adenocarcinoma arising in a background of intestinal metaplasia.Methods and results: CK7 and 20 immunostaining was performed on randomly selected surgical resection specimens from patients with Barrett's-related oesophageal adenocarcinoma (n = 30) and intestinal type gastric adenocarcinoma (n = 14) arising in a background of intestinal metaplasia. A CK7+ CK20- immunophenotype was demonstrated in 27 of 30 (90%) patients with Barrett's-related oesophageal adenocarcinoma and only three of 14 (21%) gastric adenocarcinomas. The sensitivity, specificity and positive predictive value of a CK7+/20– immunophenotype for a diagnosis of Barrett's-related oesophageal adenocarcinoma was 90%, 79%, and 90%, respectively.Conclusions: A CK7+/20– tumour immunophenotype is associated with Barrett's-related oesophageal adenocarcinoma and may be useful in accurate tumour classification, thus facilitating improving epidemiological evaluation of tumours at the oesophagogastric junction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2559.2001.01079.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Prevention of erosive oesophagitis relapse with pantoprazole (2004)
    Oxford, UK : Blackwell Science Ltd
    Alimentary pharmacology & therapeutics 20 (2004), S. 0 
    Details
    ISSN: 1365-2036
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Aim : To compare the safety and efficacy of pantoprazole and ranitidine in maintaining erosive oesophagitis healing.Methods : Gastro-oesophageal reflux disease patients (349) with endoscopically documented healed erosive oesophagitis (grade 0 or 1) were randomly assigned to receive pantoprazole (10, 20 or 40 mg/q.d.s.) or ranitidine (150 mg/b.d.). Erosive oesophagitis status was assessed endoscopically at months 1, 3, 6 and 12 or when relapse symptoms appeared (relapse = reappearance of erosive oesophagitis grade 2 within 12 months). Symptom-free days were also assessed.Results : Pantoprazole 20- and 40-mg were significantly more effective than ranitidine in maintaining healing regardless of initial erosive oesophagitis grade. Response was dose-related. After 12 months 78, 55, 46 and 21% of patients remained healed (40-, 20-, 10-mg pantoprazole and ranitidine). Pantoprazole 40-mg produced significantly more symptom-free days (83%) than ranitidine (58%). Heartburn-free days/nights were significantly higher with pantoprazole 40-mg (92 and 93%) than ranitidine (73 and 77%). The most frequent reason for discontinuation, unsatisfactory efficacy, occurred most often with ranitidine (P 〈 0.001).Conclusion : Once-daily pantoprazole therapy prevented relapse of healed erosive oesophagitis more effectively than ranitidine and with fewer heartburn days. Response to pantoprazole was dose-related. Pantoprazole 40-mg was the most effective regimen and consistent in maintaining erosive oesophagitis healing with a good safety and tolerability profile.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-2036.2004.02121.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Ambulatory gastric pH monitoring: proper probe placement and normal values (2001)
    Oxford UK : Blackwell Science Ltd
    Alimentary pharmacology & therapeutics 15 (2001), S. 0 
    Details
    ISSN: 1365-2036
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: : Gastric acid production may persist while patients are treated with proton pump inhibitors. Twenty-four-hour intragastric pH monitoring is being used to identify gastric acid in the stomach while on medical therapy.〈section xml:id="abs1-2"〉〈title type="main"〉Aim: To identify the optimal region of the stomach to demonstrate the presence of gastric acid.〈section xml:id="abs1-3"〉〈title type="main"〉Method: Probe locations confirmed with fluoroscopy after placement and prior to removal. In experiment 1, five volunteers underwent simultaneous, 24-h gastro-oesophageal pH monitoring with the pH sensors located in the gastric antrum, body, fundus and distal oesophagus. In experiment 2, five volunteers underwent simultaneous 24-h pH monitoring with sensors located side by side in the gastric fundus assessing the reproducibility of gastric pH in this region. In experiment 3, 35 volunteers underwent 24-h pH monitoring with pH sensors located in the distal oesophagus and gastric fundus. The mean percentage time for which pH 〈 4 was calculated for total, upright, and supine time periods. Results: pH profiles for the gastric fundus and body are similar—the mean percentage total time for which pH 〈 4 was 92.2% and 90.1%, respectively (P=N.S.). These values are significantly different from the antrum; pH 〈 4=54.6% (P 〈 0.01). pH values from the gastric fundus are highly reproducible (linear regression P= 0.004, r2=0.96). The normal values (mean ± 95th percentile) for percentage time gastric pH 〈 4 in the fundus were: total 95.6 ± 1.5%, upright 94.8 ± 1.8%, and supine 96.5 ± 2.3%.〈section xml:id="abs1-4"〉〈title type="main"〉Conclusion: The fundus is the optimal location to evaluate the presence of gastric acid; pH values are highly reproducible in this area. Normal values for percentage time gastric pH 〈 4 for a healthy population are now defined.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2036.2001.01011.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Recursion method and one-hole spectral function of the Majumdar-Ghosh model (2003)
    Springer
    The European physical journal 35 (2003), S. 21-31 
    Details
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract. We consider the application of the recursion method to the calculation of one-particle Green’s functions for strongly correlated systems and propose a new way how to extract the information about the infinite system from the exact diagonalisation of small clusters. Comparing the results for several cluster sizes allows us to establish those Lanczos coefficients that are not affected by the finite size effects and provide the information about the Green’s function of the macroscopic system. The analysis of this ‘bulk-related’ subset of coefficients supplemented by alternative analytic approaches allows to infer their asymptotic behaviour and to propose an approximate analytical form for the ‘terminator’ of the Green’s function continued fraction expansion for the infinite system. As a result, the Green’s function acquires the branch cut singularity corresponding to the incoherent part of the spectrum. The method is applied to the spectral function of one-hole in the Majumdar-Ghosh model (the one-dimensional $ t-J-J^{\prime}$ model at $J^{\prime }/J=1/2$ ). For this model, the branch cut starts at finite energy $\omega_0$ , but there is no upper bound of the spectrum, corresponding to a linear increase of the recursion coefficients. Further characteristics of the spectral function are band gaps in the middle of the band and bound states below $\omega_0$ or within the gaps. The band gaps arise due to the period doubling of the unit cell and show up as characteristic oscillations of the recursion coefficients on top of the linear increase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1140/epjb/e2003-00252-x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Estimating the active and total soil microbial biomass by kinetic respiration analysis (2000)
    Springer
    Biology and fertility of soils 32 (2000), S. 73-81 
    Details
    ISSN: 1432-0789
    Keywords: Key words Active microbial biomass ; Substrate-induced respiration ; Sustaining microbial biomass ; Growth-response description
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract  A model describing the respiration curves of glucose-amended soils was applied to the characterization of microbial biomass. Both lag and exponential growth phases were simulated. Fitted parameters were used for the determination of the growing and sustaining fractions of the microbial biomass as well as its specific growth rate (μ max). These microbial biomass characteristics were measured periodically in a loamy silt and a sandy loam soil incubated under laboratory conditions. Less than 1% of the biomass oxidizing glucose was able to grow immediately due to the chronic starvation of the microbial populations in situ. Glucose applied at a rate of 0.5 mg C g–1 increased that portion to 4–10%. Both soils showed similar dynamics with a peak in the growing biomass at day 3 after initial glucose amendment, while the total (sustaining plus growing) biomass was maximum at day 7. The microorganisms in the loamy silt soil showed a larger growth potential, with the growing biomass increasing 16-fold after glucose application compared to a sevenfold increase in the sandy loam soil. The results gained by the applied kinetic approach were compared to those obtained by the substrate-induced respiration (SIR) technique for soil microbial biomass estimation, and with results from a simple exponential model used to describe the growth response. SIR proved to be only suitable for soils that contain a sustaining microbial biomass and no growing microbial biomass. The exponential model was unsuitable for situations where a growing microbial biomass was associated with a sustaining biomass. The kinetic model tested in this study (Panikov and Sizova 1996) proved to describe all situations in a meaningful, quantitative and statistically reliable way.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003740000219
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    facet.materialart.
    Unknown
    Die marxistisch-leninistische Wissenschaftstheorie benötigt ein interdisziplinäres Forschungskonzept (1973)
    Berlin : Periodicals Archive Online (PAO)
    Deutsche Zeitschrift für Philosophie. 21:9 (1973) 1080 
    Details
    ISSN: 0012-1045
    Topics: Philosophy
    URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pao:&rft_dat=xri:pao:article:4085-1973-021-09-000006
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Sprunggelenksfrakturen des Erwachsenen (2000)
    Springer
    Der Chirurg 71 (2000), S. 489-502 
    Details
    ISSN: 1433-0385
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Seit 30 Jahren haben sich Indikationen und Behandlungstechniken von Sprunggelenksfrakturen des Erwachsenen in der deutschsprachigen Literatur kaum verändert. Typische Indikationen zur operativen Therapie sind Frakturen vom Typ B und C nach Danis-Weber. Konservativ werden nur isolierte unverschobene Innenknöchelbrüche und Fibulafrakturen vom Typ Weber A behandelt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001040051092
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...