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  • 1
    Electronic Resource
    Electronic Resource
    Force velocity relations in vascular smooth muscle: The influence of pH, pCa, and noradrenaline (1976)
    Springer
    Pflügers Archiv 364 (1976), S. 135-141 
    Details
    ISSN: 1432-2013
    Keywords: Vascular smooth muscle ; Force velocity relation ; pH ; Calcium ; Noradrenaline
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The kinetics of vascular smooth muscle activity was studied by means of afterloaded isotonic contractions of the tetanized rat portal vein at varied pH (8.0–5.9), pCa (3.4–2.1), and during noradrenaline incubation (0.4 μg/ml). Under control conditions (pH 7.3, pCa 2.6) the following parameters of the force velocity relation were calculated:a of Hill's equation (relating to the isometric peak tension)=0.36;b (relating to the actual muscle length)=0.19 ML/s;V M (relating to the actual muscle length)=0.56 ML/s. Within the range of pCa between 2.0 and 3.2 the amount of force generation (=ΔP) depended on the extracellular calcium level whereas the extrapolated velocity of shortening of the unloaded preparation (=V M) did not. Also pH changes between 8.0 and 6.8 as well as noradrenaline incubation at a pH of 5.9 affectedΔP quite considerably, butV M only scarcely. At a pH of 6.3, however,V M was distinctly diminished, and a reduced calcium sensitivity of the ATPase was inferred from the shift of ED50 of extracellular calcium from 0.66 mM Ca at a pH of 7.3 to 1.56 mM Ca at a pH of 6.3 (P〈0.0005). It is concluded from these results that the experimental conditions—pCa between 2.0 and 3.2, pH between 8.0 and 6.8, and noradrenaline added at a pH of 5.9—obviously change the intracellular calcium concentration which influences the number of activated interaction sites rather than the velocity of crossbridge movement.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00585181
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  • 2
    Electronic Resource
    Electronic Resource
    Force-velocity relations of the portal vein of hyperthyroid rats (1977)
    Springer
    Pflügers Archiv 372 (1977), S. 23-27 
    Details
    ISSN: 1432-2013
    Keywords: Vascular smooth muscle ; Portal vein ; Contractility ; Thyroxine ; Hyperthyroidism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of thyroxine on the elementary process of contraction of vascular smooth muscle was tested in 38 hyperthyroid and in 38 control rats. Hyperthyroidism was induced by i.p. injections of triiodthyronine or 1-thyroxine for 2 weeks. By means of afterloaded isotonic contractions of the tetanized portal vein force velocity relations were calculated. There was a slight increase in both the extrapolated velocity of shortening at zero load [from 0.93±0.04 ML/s (control rats) to 1.03±0.04 ML/s (hyperthyroid rats;P〈0.05)], and the peak force generation (from 14.8±0.4 mN to 16.1±0.4 mN;P〈0.005). The maximum of mechanical power development at a distinct extent of afterload was augmented from 1.35±0.06 μW/ML to 1.68±0.06 μW/ML (P〈0.0005). The influence of thyroxine on the elementary process of contraction in vascular smooth muscle is discussed in connection with the much stronger effect of hyperthyroidism on cardiac muscle contraction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00582202
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  • 3
    Electronic Resource
    Electronic Resource
    Force velocity relationships in vascular smooth muscle (1975)
    Springer
    Pflügers Archiv 356 (1975), S. 33-45 
    Details
    ISSN: 1432-2013
    Keywords: Vascular Smooth Muscle ; Rat Portal Vein ; Force Velocity Relation ; Velocity of Shortening ; Sliding Filament Mechanism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Force velocity relationships of isolated vascular smooth muscle preparations were examined in the tetanized rat portal-anterior mesenteric vein by means of afterloaded isotonic contractions. Lowering of the temperature from 37°C to 25°C caused an average decrease of the following parameters: maximal velocity of shortening at zero load from 0.51 to 0.28 muscle length/sec; maximal rate of tension increase (dT/dt) from 847 to 362 dyn/sec; mechanical tension developed at the maximum ofdT/dt from 43 to 34% of the peak force generation; constantb of Hill's equation from 0.18 to 0.09 muscle length/sec. The latency was prolonged from 0.33 to 0.56 sec, and the time-to-maximum ofdT/dt from 0.9 to 1.6 sec. Between 27°C and 37°C the followingQ 10 values were calculated: for the maximal velocity of shortening at zero load 1.56; for the maximal rate of tension increase 1.88; for the latency 1.63. No distinct influence of temperature could be observed on the extent of isotonic shortening at zero load (0.69 muscle length at 37°C), on the extent of peak force generation (1107 dyn at 37°C), and on constanta of Hill's equation (0.35 at 37°C). It is concluded that parameters of contraction velocity in vascular smooth muscle depend on temperature, whereas the extent of contraction is independent of temperature. These findings are discussed in connection with the theory of the sliding-filament mechanism.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00583519
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  • 4
    Electronic Resource
    Electronic Resource
    The temperature dependence of parallel and series elastic elements in the vascular smooth muscle of the rat portal vein (1978)
    Springer
    Pflügers Archiv 378 (1978), S. 25-30 
    Details
    ISSN: 1432-2013
    Keywords: Series elastic element ; Length-tension relation ; Portal vein ; Vascular smooth muscle ; Temperature dependence of elasticity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The stiffness of a parallel (PE) as well as of a series elastic element (SE) in the isolated rat portal vein was determined at 37° C and at 25° C. The lengthtension curve of the PE was obtained by a stepwise lengthening of the preparation and showed no temperature dependence for the element: the mean extension of the PE was 48.8% of the optimum lengthL 0 at 37° C, and 47.3% ofL 0 at 25° C when loaded with the maximum active forceT 0. The maximum force occurred at both temperatures with the same muscle length. Even the stiffness factor, i.e. the slope ‘k’ of the linear functiondT/dL=kδT+c showed no temperature dependence. The series elasticity was determined by means of the quick-release technique from afterloaded isometric contractions of the tetanized preparation. A distinct temperature influence was revealed by the decrease of the mean SE extension from 13.5% ofL 0 at 37° C to 10.9% ofL 0 at 25° C (P〈0.0005). The stiffness factor, normalized to the actual muscle length, was 12.0 per ML at 37° C and 14.7 per ML at 25° C (P〈0.025). The values obtained for the portal vein are equivalent to those calculated for other smooth muscle preparations but the stiffness of series elasticity is well below that found in the cardiac and skeletal muscle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00581954
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  • 5
    Electronic Resource
    Electronic Resource
    The dynamics of cross-bridge movement in vascular smooth muscle estimated from a single isometric contraction of the portal vein: The influence of temperature and calcium (1978)
    Springer
    Pflügers Archiv 378 (1978), S. 31-36 
    Details
    ISSN: 1432-2013
    Keywords: Force-velocity relation ; Vascular smooth muscle ; Portal vein ; Calcium ; Temperature ; Contractility ; Staircase phenomenon
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The velocity of the contractile elementV CE of the rat portal vein during a single isometric twitch was calculated from the ratio of the rate of tension increase (dT/dt) to the stiffness (dT/dL) of the series elastic element. This stiffness was considered as a linear function of tension (dT/dL=k · T), and thus the respective term wasV CE=(dT/dt)/(kT). A polynome of the 10th order was fitted to the time course of tension change within the first seconds of stimulation. From this function, the instantaneous values of forceT, rate of tension increasedT/dt, as well as the ratio(dT/dt)/T were computed. The series elasticity was treated as the respective stiffness factor ‘k’.V max isV CE extrapolated to zero load, and this value gives an index of the turnover rate of the myosin cross-bridges. The experiments were carried out at different temperatures (37° C, 30° C, and 25° C) as well as at different intracellular calcium levels occurring as a staircase phenomenon in the first contractions after a period of non-stimulation of 20 min. With increasing temperature,T remained constant but there was an increase inV max (Q 10=1.9), peakV CE (Q 10=1.8) and in (dT/dt)max (Q 10=1.8). Furthermore, this so-called ‘tachytropic’ effect of temperature showed a reduction of the time to the maximumdT/dt (Q 10=1.4), and to the peakV CE (Q 10=1.2). During a staircase cycle the parameters describing the contractile state, i.e. theV max, the time to maximumdT/dt, and the time to peakV CE remained constant.T, maximumdT/dt and peakV CE were, however, considerably increased. These results are typical of the socalled ‘polytropic’ effect of calcium. The experimental results obtained from the isometric force-velocity relation were compared with those calculated by means of isotonic contractions in previous experiments. There were similar changes in the dynamics of contraction, irrespective of the method used for calculation ofV max; this was the case in experiments with varied temperatures and calcium levels. Therefore the determination ofV max from a single isometric contraction seems to be a suitable method of describing the elementary process of contraction in vascular smooth muscle. This method showed a higher time resolution as compared with other methods using isotonic contractions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00581955
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  • 6
    Electronic Resource
    Electronic Resource
    166. Die Behandlung hochdifferenzierter Schilddrüsencarcinome - Thyreoidektomie oder stadiengerechtes Vorgehen? (1978)
    Springer
    Langenbeck's archives of surgery 347 (1978), S. 657-657 
    Details
    ISSN: 1435-2451
    Keywords: Thyroid carcinoma, well-differentiated ; Thyroidectomy, total ; Thyroidectomy, neartotal ; Hochdifferenzierte Schilddrusencarcinome ; Totale Thyreoidektomie ; Intrakapsuläre Resektion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Von 310 Schilddrüsencarcinomen, die von 1955-1975 zur Behandlung kamen, lagen in 34,3 % follikulare und in 28,1% papilläre Schilddrusencarcinome vor. Die Verlaufsbeobachtung hinsichtlich Rezidivrate und Überlebenszeit gestattet folgendes therapeutisches Konzept: Papilläre Schilddrusencarcinome ohne Lymphknotenmetastasen sollten durch totale Lobektomie tier befallenen Seite und subtotaler Lobektomie tier nicht erkrankten Seite therapiert werden, follikulare Carcinome wegen tier Möglichkeit einer erfolgreichen Radiojodnachbehandlung bei Auftreten von Fernmetastasen durch beidseitige intrakapsuläre Thyreoidektomie.
    Notes: Summary Of 310 treated cases of thyroid carcinoma between 1955 and 1975, 34.3 % were of the follicular type, while 28,1% were papillar carcinomas. Observations regarding rate of recurrence and mortality yielded the following therapeutic concept: Papillar carcinomas without lymph node metastases should be treated with total lobectomy of the affected and subtotal lobectomy of the unaffected side. Follicular carcinomas should be treated with bilateral intracapsular thyroidectomy, since postoperative radioiodine treatment for metastases has been successful.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01579459
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  • 7
    Electronic Resource
    Electronic Resource
    The contractility of venous vascular smooth muscle in spontaneously hypertensive or renal hypertensive rats (1979)
    Springer
    Basic research in cardiology 74 (1979), S. 21-34 
    Details
    ISSN: 1435-1803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Der Einfluß arterieller Hypertonie auf die Kontraktilität von Gefäßmuskeln wurde über Kraft-Geschwindigkeits-Beziehungen an der isolierten, tetanisierten Portalvene spontan-hypertensiver (SHR) und renal-hypertensiver Ratten (RHR) untersucht. Bei spontan-hypertensiven Tieren (n=23, mittlerer arterieller Blutdruck=166±4 mm Hg) wurden die Kraft-Geschwindigkeits-Beziehungen aus einer größeren Anzahl nachbelasteter isotoner Kontraktionen oder aus einzelnen isometrischen Kontraktionen unter Berücksichtigung der Serienelastizität berechnet. Die Serienelastizität war bei den SHR-Tieren größer als bei der Vergleichsgruppe normotoner Tiere (NR). Sowohl die isometrische als auch die isotonische Kraft-Geschwindigkeits-Beziehungen wurden durch die spontane Hypertonie in gleicher Weise beeinflußt. Verglichen mit den Ergebnissen an NR nahm die maximale Geschwindigkeit des Kraftanstiegs um den Faktor 1.4 zu. Die Kraftamplitude stieg um den Faktor 1.5 an, während die Geschwindigkeit der lastfreien Verkürzung als ein Maß für die Geschwindigkeit der Querbrückenbewegung konstant blieb (sog. polytroper Effekt). Die Veränderung der Kontraktilität der Portalvene in SHR ist somit nicht durch eine Beeinflussung der Dynamik der einzelnen Querbrücken hervorgerufen worden; der elementare Kontraktionsprozess bleibt unbeeinflußt. Die gesteigerte Kraftentwicklung ist möglicherweise auf einen durch Anstieg des intrazellulären Kalzium-Spiegels bedingten Rekrutierungsprozeß zurückzuführen. Bei den renal hypertensiven Tieren (Gruppe I: 75 Tage nach Klammerung der linken Nierenarterie, n=14, mittlerer arterieller Blutdruck=175±2 mm Hg; Gruppe II: 138 Tage nach der Klammerung, n=4, 177±10 mm Hg) war ein geringer Anstieg der Kraftentwicklung der Portalvene vor allem in Untersuchungen an Ratten mit langdauernder Hypertonie (RHR II) zu beobachten (15.6±1.1 mN in NR, 18.4±1.0 mN in RHR II). Die lastfreie Verkürzungsgeschwindigkeit wurde deutlich von 0.86±0.03 ML/s auf 0.61±0.09 ML/s vermindert (P〈0.0025; sog. tachytroper Effekt). Die erhobenen Befunde lassen einen unterschiedlichen Einfluß der beiden Formen einer arteriellen Hypertonie auf den elementaren Kontraktionsprozeß der Portalvene der Ratte erkennen. Die Dynamik des Querbrückenzyklus wird nur bei der renalen Hypertonie, nicht aber bei der spontanen Hypertonie beeinflußt.
    Notes: Summary The influence of arterial hypertension on the contractility of venous smooth muscle was studied by using force-velocity relations derived from the isolated tetanized portal vein of spontaneously hypertensive (SHR) or renal hypertensive rats (RHR). The results were compared with those obtained from corresponding normotensive rats (NR). The portal vein contractility of SHR was determined by the analysis of either a single isometric contraction or of a number of afterloaded isotonic contractions. The series elasticity needed to calculate the shortening velocity of the contractile element was found to be greater in SHR than in NR. Both the isometric and the isotonic force-velocity relations were shifted similarly by the spontaneous hypertension. The maximum rate in tension increase was greater by a factor of 1.4 and the force generation was increased by a factor of 1.5 as compared with the results obtained from the NR. The velocity of shortening of the unloaded preparation remained constant, which indicates that the turnover rate of the myosin linkages, i.e. the elementary process of contraction, was unchanged (the so-called polytropic effect). The augmentation in force generation is probably caused by a recruitment process induced by an increase in the intracellular calcium level. In RHR a slight increase in the force generation of the portal vein from 15.6±1.1 mN to 18.4±1.0 mN was seen in rats which had been submitted to a period of arterial hypertension of about 20 weeks. The speed of isotonic shortening extrapolated to zero load was considerably reduced from 0.86±0.03 ML/s to 0.61±0.09 ML/s (P〈0.0025); this is the so-called tachytropic effect. The results revealed a different influence on the elementary process of vascular smooth muscle contraction for both types of arterial hypertension. The dynamics of the cycling myosin linkages were only affected by renal hypertension whereas with spontaneous hypertension the dynamics remained constant.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01907682
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  • 8
    Electronic Resource
    Electronic Resource
    Therapy of breast cancer (1978)
    Springer
    Langenbeck's archives of surgery 346 (1978), S. 65-79 
    Details
    ISSN: 1435-2451
    Keywords: Breast cancer ; Therapeutical modalities ; Surgical therapy ; Adjuvant chemotherapy ; Radiation therapy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01261394
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  • 9
    Electronic Resource
    Electronic Resource
    Diagnostik und Therapie des primären Hyperparathyreoidismus (1978)
    Springer
    Langenbeck's archives of surgery 346 (1978), S. 219-234 
    Details
    ISSN: 1435-2451
    Keywords: Primary hyperparathyroidism (PHPT) ; Hypercalcemic crises ; Diagnostic procedures ; Therapy ; Results
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Anhand des Krankengutes der Chirurgischen Universitätsklinik Göttingen (51 Patienten) wird auf die klinische Symptomatologie, diagnostische Verfahren, Differentialdiagnostik, operativ taktisches Vorgehen und die Langzeitnachuntersuchungsergebnisse bei Patienten mit primärem Hyperparathyreoidismus eingegangen. Neben den klinischen Befunden und radiologischen Kriterien kommt der Bestimmung der ionisierten Serumcalciumfraktion, den Befunden der Beckenkammbiopsie sowie der Bestimmung der Parathormonspiegel größte Bedeutung zur Sicherung der Diagnosestellung zu. Zur Lokalisationsdiagnostik bewährt sich vor allem bei Reoperationen die Parathormonbestimmung mittels selektiver Halsvenenkatheterisierung. Unter 51 Patienten wurde 5mal eine hypercalcämische Krise mit lebensbedrohlicher Symptomatologie beobachtet. Hierbei ist die Notfalloperation absolut indiziert. Eine postoperative persistierende Hypercalcämie sowie Rezidive wurden in 3,9 % beobachtet. Die erfolgreiche Adenomexstirpation (in 15 % lagen multiple Adenome vor) ist die Therapie der Wahl, lediglich bei vorliegender Hyperplasie ist die subtotale Parathyreoidektomie indiziert.
    Notes: Summary Of 51 patients with primary hyperparathyroidism (2 patients with MEN, Type 1 clinical symptomatology, diagnostic procedures, differential diagnosis, operative strategy and long-term results are being reported. Aside from clinical findings and radiologic signs in our hands determination of the ionized serum calcium fraction, results of chrest bone biopsies and parathormone determinations are best parameters to substantiate the diagnosis of PHPT. Parathormone radioimmunassay determination is very helpful in localizing the adenoma, especially in cases of reoperations. Five patients were seen in acute hypercalcemic crises, in which emergency operations are absolutely indicated. Postoperative hypercalcemia and recurrencies were observed in 3.9 %. Successful extirpation of parathyroid adenomas (15 % multiple adenomas were found) is the therapy of choice in PHPT, only in cases with hyperplasia subtotal parathyroidectomy is indicated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01256401
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  • 10
    Electronic Resource
    Electronic Resource
    275. Die Oesophagojejunoplicatio als Rekonstruktionsverfahren nach totaler Gastrektomie (1979)
    Springer
    Langenbeck's archives of surgery 349 (1979), S. 617-617 
    Details
    ISSN: 1435-2451
    Keywords: Esophagojejunoplication ; Oesophagojejunoplicatio
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In dem Film werden die pathophysiologischen überlegungen, die zur Entwicklung der Oesophagojejunoplicatio als Rekonstruktionsverfahren nach Gastrektomie geführt haben ebenso wie die operative Technik und die Ergebnisse dieses Verfahrens dargestellt.
    Notes: Summary In the movie the pathophysiological background, the surgical technique and the results of the esophagojejunoplication — a special method of reconstruction after total gastrectomy — are shown.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01729736
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