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51.
大鼠血小板中的神经肽Y及其对血管收缩的影响   总被引:20,自引:0,他引:20  
杨耀芳  杨丽华 《生理学报》1993,45(4):400-404
特异性放射免疫分析显示大鼠血小板与富血小板血浆(PRP)分别含NPY免疫活性物质90±16ng/10~7血小板与93±19ng/ml,大大高于普通血浆(1.2±0.1ng/ml)与贫血小板血浆(PPP)(1.7±0.3 ng/ml)中的含量(P<0.001)。血小板样品HPLC各馏分的NPY放免活性峰位与标准NPY的峰位相符。PRP经胶原最大程度聚集后,血小板内的NPY浓度降为34±5 ng/10~7血小板,而PPP中的NPY浓度则升高到26±4 ng/ml。1.6 ml PRP经胶原作用产生最大程度聚集,由此分离所得的PPP引起离体灌流大鼠尾动脉收缩,张力上升380±80 mg;上述PPP经NPY抗血清处理后引起尾动脉收缩的幅度显著减小(190±40 mg,P<0.001)。而1 nmol/L人工合成NPY并不引起血管收缩。结果表明大鼠血小板中含有大量NPY,在不可逆聚集时可以释放,释放的NPY可能参与血小板聚集时释放物质的缩血管效应。  相似文献   
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The current report describes the chemical investigation and biological activity of extracts produced by three fungal strains Fusarium oxysporum, Penicillium simplicissimum, and Fusarium proliferatum isolated from the roots of Piper nigrum L. growing in Vietnam. These fungi were namely determined by morphological and DNA analyses. GC/MS identification revealed that the EtOAc extracts of these fungi were associated with the presence of saturated and unsaturated fatty acids. These EtOAc extracts showed cytotoxicity towards cancer cell lines HepG2, inhibited various microbacterial organisms, especially fungus Aspergillus niger and yeast Candida albicans (the MIC values of 50–100 μg/mL). In α-glucosidase inhibitory assay, they induced the IC50 values of 1.00-2.53 μg/mL were better than positive control acarbose (169.80 μg/mL). The EtOAc extract of F. oxysporum also showed strong anti-inflammatory activity against NO production and PGE-2 level. Four major compounds linoleic acid (37.346 %), oleic acid (27.520 %), palmitic acid (25.547 %), and stearic acid (7.030 %) from the EtOAc extract of F. oxysporum were selective in molecular docking study, by which linoleic and oleic acids showed higher binding affinity towards α-glucosidase than palmitic and stearic acids. In subsequent docking assay with inducible nitric oxide synthase (iNOS), palmitic acid, oleic acid and linoleic acid could be moderate inhibitors.  相似文献   
53.
滇金丝猴(Rhinopithecusbieti)现状及其保护对策研究   总被引:3,自引:0,他引:3  
滇金丝猴(Rhinopithecusbieti)是我国特有的珍稀濒危动物,生活在海拔3800~4300m的原始冷杉林中,但有时也会在4300~4700m的低矮灌丛、草甸和流石滩上活动达数小时之久,甚至能跨越近千米的无林高海拔地带,因而它们是海拔分布最高的非人灵长类。松萝是它们的主要食物,取食松萝的时间占总取食时间的91%。猴群活动范围可达近百平方公里。笔者在历时8年的野外考察中,已查明这一物种的全部现存自然种群只有13个,分布在云南的德钦、兰坪、潍西、丽江和西藏的芒康这五县境内,其现存种群数量为1000~1500只;所有现存自然种群几乎均处在相互隔离的状态,群间已不可能进行基因交流,充分表明它们已到达灭绝边缘。然而其栖息地内的商业伐木规模仍在继续扩大,周围的人口压力正在不断增加,各猴群均面临不同程度的偷猎压力。这一现状委实令人担忧。如何拯救这一“国宝”应引起我国保护学家和各级政府有关职能部门的重视  相似文献   
54.
Summary The appearance of perinucleolar electron-dense spots in the nuclei of macroconidia ofNeurospora crassa incubated at 46C and their disaggregation after shift-down to 25 C have been investigated by high-resolution autoradiography after (5-3H) uridine pulses with or without chase periods. The RNA of these ribonucleoprotein-rich dense spots has been found to originate mainly from the heatsensitive nucleolus; after return to 25 C, the nucleolar activity was recovered and the RNA material stored either in an unprocessed or a mature rRNA form in the dense spots was found to be progressively extruded into the cytoplasm.  相似文献   
55.
Summary The possibility of giving C. parvum intrapleurally (i.p.) was investigated. C. parvum was given post-operatively either i.p. only or i.p. and intravenously (i.v.) simultaneously. The dose varied from 0.1–10 mg i.p. All patients had been operated for a bronchial carcinoma. Results: (1) Subjective complaints of either dyspnoea, thoracic pain, chills or nausea occured in 31 of 63 patients. No clear dose relation was found. A feeling of discomfort and fever could occur for another 3–4 days after the above more acute symptoms had disappeared. (2) Increased fever (0.5° C) occurred in 71% of the patients injected i.p. only. (3) No anaphylactic reaction was observed. (4) Increased total white blood cell counts (<20%) occurred in 38 patients. The WBC increase was mainly due to higher number of neutrocytes and granulocytes. Total lymphocyte, monocyte, eosinophilic, and basophilic granulocytes values per mm3 circulating blood remained unchanged, except at the dose of 7 mg C. parvum i.p. when monocyte values were increased significantly from 576±247 to 1100±578/mm3. (5) Moderate to severe effusions were observed radiologically in three patients after C. parvum intrapleurally.The study group is: M. Kaufmann, J. Stjernswärd (Ludwig Institut for Cancer Research, Lausanne Branch, Switzerland), M. Zelen, K. Stanley (Frontier Science and Technology Research Foundation, Inc. Amherst, New York, USA), D. S. Freestone, R. Bomford, M. T. Scott, T. Priestman (The Wellcome Research Laboratory, Beckenham, England), C. Mouritzen, G. Ahlbom (Dept. of Thoracic and Cardiovascular Surgery, Aarhus Kommunehospital, Aarhus, Denmark), N. Konietzko, D. Greschuchna (Ruhrland Klinic, Essen-Haidhausen, Germany), P. Hilgard (Innere Klinik und Poliklinik [Tumorforschung] Essen, Germany), J. Vogt-Moykopf, D. Zeidler, H. Toomes (Thoraxchirurgische Spezial-Klinik, Heidelberg-Rohrbach, Germany), F. Krause, R. Rios (Thoraxchirurgische Abt., Fachkrankenhaus für Lungen- und Bronchialerkrankungen, Löwenstein, Germany), J. Orel, M. Benedik, B. Hrabar (Clinical Center, Dept. of Thoracic Surgery, Ljubljana, Yugoslavia), S. Plesnicar (The Institute of Oncology, Ljubljana, Yugoslavia), H. A. Rostad, J. R. Vale (Rikshospital, Oslo, Norway), S. Hagen, S. Birkeland, (Ulleval Hospital, Oslo, Norway), T. Harbitz, R. Nissen-Meyer (Aker Hospital, Oslo, Norway), L. Rodriguez, V. O. Björk, K. Böök (Karolinska Sjukhuset, Thoracic Clinic, Stockholm, Sweden), E. Gradel, J. Hasse, P. Holbro (Kantonsspital, Thoraxchirurgische Klinik, Basel, Switzerland), L. Eckmann (Tiefenauspital, Chir. Univ.-Klinik, Bern, Switzerland), B. Nachbur, T. Liechti (Inselspital, Dept. of Thoracic and Cardiovascular Surgery, Bern, Switzerland), H. Cottier (Inst. of Pathology, Inselspital, Bern, Switzerland), W. Maurer, M. Kaufmann, P. Froelicher (Bürgerspital, Surgical Dept., Solothurn, Switzerland), H. Denck, N. Pridun (Krankenhaus der Stadt Wien-Lainz, Chir. Abt., Vienna, Austria), K. Karrer (Institute for Cancer Research, University of Vienna, Austria) Reprint requests should be addressed to any of the members listed above, or to the Ludwig Lung Cancer Trial, Operation Office, LICR, CH-1066 Epalinges, Switzerland. (For Current Contents, etc., please use above address)  相似文献   
56.
1. The effect of dimethyl sulfoxide (Me2SO) and ethylene glycol on two different preparations of the sarcoplasmic reticulum, i.e. native membranes and membranes whose phospholipids were hydrolyzed by phospholipase A, were investigated using ATP and p-nitrophenylphosphate as substrates. 2. Me2SO and ethylene glycol inhibit both calcium-dependent ATP hydrolysis and ATP-supported calcium transport by native vesicles. 3. In contrast, calcium-dependent p-nitrophenylphosphatase activity as well as p-nitrophenyl-phosphate-supported calcium transport are activated by both agents at concentrations lower than 30% (v/v). 4. Me2SO strongly stimulates p-nitrophenylphosphate activity of vesicles treated with phospholipase A, but has relatively little effect on p-nitrophenylphosphatase activity of native vesicles. 5. Up to a concentration of approximately 40% Me2SO (v/v) the inhibiting effect on the calcium-dependent ATPase is fully reversible, but only partially reversible on calcium transport. 6. In the concentration range where Me2SO inhibits ATP hydrolysis and calcium transport, it does not affect ATP binding to the membranes nor calcium-dependent formation of phospho-protein. 7. The rate of dephosphorylation as well as the rate of Pi exchange between ATP and ADP are markedly reduced by the presence of 30% Me2SO (v/v). 8. While Me2SO inhibits passive calcium efflux, ethylene glycol produces a considerable activation. 9. ADP-dependent calcium efflux and ATP synthesis are activated by 15% Me2SO (v/v). Ethylene glycol reduces both activities. 10. The results suggest that the respective substrate-enzyme complexes are differently affected by the agents, resulting either in inhibition or stimulation  相似文献   
57.
李贵山  梁妮 《蛇志》1991,3(4):4-5
本文选用金黄地鼠的微血管,利用显微高速摄影技术,放大微观流场和血细胞,连续地“冻结”短瞬间的变化状态,把物理图象呈现在胶片上,经图像分析和数据处理,从定性及定量方面研究血液微流变学,为生命科学和医学研究提供了又一种新的方法。  相似文献   
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