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51.
In elvers (Anguilla anguilla) imported yearly to a fish farm in Hungary the regular occurrence of a Myxobolus infection was recorded. The parasite produces oval or spherical plasmodia of 0.1–0.2·0.07–0.12mm in the subcutaneous and intermuscular connective tissue of the head. In each piasmodium about 200 to 400 spores develop which differ morphologically from the spores of all Myxobolus species known from the eel and other fishes. Based upon the characteristic location of plasmodia and spore morphology, this parasite is described as a new species, Myxobolus kotlani. 相似文献
52.
Whole leaf hydrocarbons of six species of Phacelia were investigated for their variability among natural Californian populations, and for adaptive 相似文献
53.
Changes in activity levels of important enzymes of carbohydratemetabolism (and ß-amylases, sucrose synthetase, acidinvertase, acid phosphatase, glucose phosphate isomerase, aldolase,phosphofructokinase and pyruvate kinase) during seed developmentwere determined. Changes in the activities of these enzymesand their functional significance in developing seeds are described.A close correlation was found between the stage of maximum carbohydrateoxidation and the accumulation of reserve materials in the developingseeds.
1Present address: School of Agriculture and Forestry, Universityof Melbourne, Parkvilie 3052, Victoria, Australia.
2Present address: School of Botany, University of Melbourne,Parkville 3052, Victoria, Australia. (Received October 8, 1982; Accepted January 10, 1983) 相似文献
54.
A Johnson F A Blumenstock A B Malik 《Journal of applied physiology (Bethesda, Md. : 1985)》1983,55(5):1480-1485
We examined the effect of complement depletion on lung fluid and protein exchange after thrombin-induced pulmonary thromboembolization. Sheep were prepared with lung lymph fistulas to assess pulmonary transvascular fluid and protein dynamics. Studies were made in three groups: in group I (n = 5) pulmonary thromboembolization (PT) was induced by an iv infusion of thrombin (55.0 +/- 12.9 NIH U/kg); in group II (n = 6) cobra venom factor (CVF) was given ip (94.5 +/- 18.8 U/kg/day) for 2 days to deplete complement, and then thrombin (66.4 +/- 37.0 NIH U/kg) was infused to raise pulmonary vascular resistance to the same level as in group I; in group III (n = 10) left atrial pressure (Pla) was increased by 10-15 Torr in normal animals by inflation of a Foley balloon catheter. In group I, thrombin infusion caused an increase in pulmonary lymph flow (Qlym) with a gradual increase in the lymph-to-plasma protein concentration ratio (L/P). In complement-depleted sheep, thrombin caused a transient increase in Qlym, which was associated with a decrease in L/P. In group I an increase in Pla further increased Qlym but without a change in L/P, indicating an increase in lung vascular permeability to proteins; whereas in the decomplemented-thrombin sheep raising Pla increased Qlym but decreased L/P. Results in the latter group were similar to those obtained in normal animals after left atrial hypertension (group III). Therefore the complement system participates in the increase in lung vascular permeability following thrombin-induced microembolization. 相似文献
55.
Rainer Zocher Ullrich Keller Horst Kleinkauf 《Biochemical and biophysical research communications》1983,110(1):292-299
Covalently bound intermediates of enniatin B synthesis could be isolated from enniatin synthetase by treatment with performic acid. By comparison with products of mild alkaline cleavage of authentic enniatin B they could be identified as the dipeptide D-2-hydroxyisovaleryl-N-methylvaline and the corresponding tetrapeptide. Synthesis of enniatins apparently proceeds via condensation of dipeptides. This was confirmed by the use of the substrate analogue isovaleric acid, which has shown to be a strong inhibitor for enniatin synthesis by formation of N-isovaleryl-N-methyl valine. 相似文献
56.
Prof. Dr. Rainer H. Lange A. R. Soames Raymond Coleman 《Cell and tissue research》1974,153(2):167-173
Summary Crystalline inclusions in parathyroid gland cell nuclei of Rana temporaria were studied by electron microscopy using a specimen tilting stage. Images were analysed by optical diffraction. Results were compared with X-ray and electron microscopic data of trigonal bovine liver catalase to which a striking resemblance of the inclusions was found.We are grateful to Professor R. Mosebach (Giessen) for discussions, to the Deutsche Forschungsgemeinschaft for a grant (La 229/4) and instruments and to Messrs. Spindler & Hoyer, Göttingen and Messrs. Rank Precision Instruments, Nürnberg for putting apparatus at our disposal and performing diffraction photographs. 相似文献
57.
58.
Summary Clinical observations and the light and electron microscopic appearance of the adrenal cortex are described in a case of Cushing's disease associated with adrenocortical hyperplasia and a basophilic adenoma of the pituitary gland. The electron microscopic investigation concentrates upon the occurrence of osmiophil material in the different cytoplasmic compartments of the cell type rich in organelles and relatively poor in paraplasmic inclusions. It seems that the observation of osmiophil material in the perinuclear space, the mitochondrial matrix, Golgi vacuoles, and cytoplasmic vesicles has been made possible by a rather long fixation in Wohlfarth-Bottermann's chromium-osmium fixative. Mitochondria and related particles (named X-Einschlüsse) may contain a light center with a few dense filaments and masses resembling those described by other authors as being of deoxyribonucleic acid nature. Relatively large Golgi complexes are found, sometimes in close topographic relation with a centriole. A large population of osmiophil bodies (lipid droplets, pigment granules, microbodies) is described. Apart from these findings the cytoplasmic organization in the tissue studied is similar to that of the adrenal cortex as described in other mammals. The observations are discussed with respect to hypotheses about lipid droplet formation and to the possibility of artifacts due to preparation procedures.
Herrn Prof. Dr. med. W. Bargmann zum 60. Geburtstag gewidmet. — Herrn Prof. Dr. E. Uehlinger, Direktor des Pathologischen Instituts der Universität Zürich, danken wir für die Überlassung des Materials und für die freundlicherweise zur Verfügung gestellte pathologisch-anatomische Diagnose, dem Schweizerischen Nationalfonds für die Unterstützung und Frau Jäger, Mlle. Challamel und Herrn Krieger für die Ausführung der histologischen und photographischen Arbeiten. 相似文献
Herrn Prof. Dr. med. W. Bargmann zum 60. Geburtstag gewidmet. — Herrn Prof. Dr. E. Uehlinger, Direktor des Pathologischen Instituts der Universität Zürich, danken wir für die Überlassung des Materials und für die freundlicherweise zur Verfügung gestellte pathologisch-anatomische Diagnose, dem Schweizerischen Nationalfonds für die Unterstützung und Frau Jäger, Mlle. Challamel und Herrn Krieger für die Ausführung der histologischen und photographischen Arbeiten. 相似文献
59.
Calcium dependence of the thrombin-induced increase in endothelial albumin permeability 总被引:4,自引:0,他引:4
Lum H.; Del Vecchio P. J.; Schneider A. S.; Goligorsky M. S.; Malik A. B. 《Journal of applied physiology》1989,66(3):1471-1476
We examined whether the increase in endothelial albumin permeability induced by alpha-thrombin is dependent on extracellular Ca2+ influx. Permeability of 125I-albumin across confluent monolayers of cultured bovine pulmonary artery endothelial cells was measured before and after the addition of 0.1 microM alpha-thrombin. In the presence of normal extracellular Ca2+ concentration ([Ca2+]o, 1000 microM), alpha-thrombin produced a 175 +/- 10% increase in 125I-albumin permeability. At lower [Ca2+]o (100, 10, 1, or less than 1 microM), alpha-thrombin caused a 140% increase in permeability (P less than 0.005). LaCl3 (1 mM), which competes for Ca2+ entry, blunted 38% of the increase in permeability. Preloading endothelial monolayers with quin2 to buffer cytosolic Ca2+ (Cai2+) produced a dose-dependent inhibition of the increase in 125I-albumin permeability. Preincubation with nifedipine or verapamil was ineffective in reducing the thrombin-induced permeability increase. A 60 mM K+ isosmotic solution did not alter base-line endothelial permeability. alpha-Thrombin increased [Ca2+]i in a dose-dependent manner and the 45Ca2+ influx rate. Extracellular medium containing 60 mM K+ did not increase 45Ca2+ influx, and nifedipine did not block the rise in 45Ca2+ influx caused by alpha-thrombin. Ca2+ flux into endothelial cells induced by alpha-thrombin does not occur through voltage-sensitive channels but may involve receptor-operated channels. In conclusion, the increase in endothelial albumin permeability caused by alpha-thrombin is dependent on Ca2+ influx and intracellular Ca2+ mobilization. 相似文献
60.
We compared the pulmonary transvascular fluxes of transferrin and albumin in the intact sheep lung. Anesthetized sheep were prepared with lung lymph fistulas. The vascular blood pool was marked with 99mTc-erythrocytes, autologous transferrin was labeled with 113mIn, and albumin was labeled with 125I. Samples of blood, plasma, lymph, and lung were obtained up to 180 min after tracer infusion. Lymph tissue radioactivities were corrected for the intravascular component and expressed as extravascular-to-plasma concentration ratios. Clearance of transferrin and albumin from the plasma space followed a two-compartment model. The clearance rate constant was 2.1 +/- 0.1 x 10(-3) min for albumin and 2.4 +/- 0.1 x 10(-3) min for transferrin (P less than 0.05). Lymph-to-plasma ratios for albumin and transferrin were not different. However, the extravascular-to-plasma ratio for albumin was greater than transferrin (P less than 0.05). The lymph and lung data were deconvoluted for the plasma input function and fit to a two-compartment model. The results indicate that albumin and transferrin have similar permeabilities across the vascular barrier but have different pulmonary circulation to lymph kinetics because the extravascular volume of distribution of albumin is greater than transferrin. 相似文献