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DU Yi-mei TANG Ming LIU Chang-jin HONG Zhi-gang KE Qin-mei DI Jiu-fang LUO Hong-yan HU Mou-xian HU Xin-wu XI Jiao-ya TANG Bi Jurgen Hescheler 《园艺学报》2004,20(9):1537-1541
AIM: To determine the role of Kv1.2, Kv1.5, Kv2.1 in the hypoxia pulmonary vasoconstriction (HPV). METHODS: Male Wistar rats were divided into two groups: normoxic group and hypoxic group. The single smooth muscle cell was obtained from pulmonary artery of Wistar rats with acute enzymatic digestion method. The conventional whole-cell patch clamp technique was used to record the resting membrane potential (Em) and the potassium currents of voltage-gated potassium channel (IKv) in rat pulmonary arterial smooth muscle cells (PASMC). Intracellular application of Kv1.2/Kv1.5/Kv2.1 antibodies (1∶125) was conducted through the whole-cell patch clamp system. RESULTS: ① Em of PASMC was depolarized after 24 h hypoxia compared with that of control cells . IKv of PASMC was decreased after 24 h hypoxia, . ② The mixture of Kv1.2/Kv1.5/Kv2.1 antibodies depolarized Em and inhibited IKv in PASMC from normoxic rat, whereas the mixture of Kir2.1/Kir2.3/Kir4.1 antibodies had no effects on them. ③ The mixture of Kv1.2/Kv1.5/Kv2.1 antibodies and the mixture of Kir2.1/Kir2.3/Kir4.1 antibodies had no effects on IKv and Em from rats hypoxic for 24 h. CONCLUSION: Kv1.2, Kv1.5, Kv2.1 might be oxygen sensitive potassium channels which mediated HPV. 相似文献
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The role of calcium in the secretion of growth hormone (GH) has been examined in vivo in immature domestic fowl. Chicks reared on a low calcium (0.16% calcium in the feed) diet showed a reduced growth rate, compared with those on a normal (0.86%) calcium diet and had lower basal levels of plasma GH 1, 5, 10 and 15 d after calcium deprivation, but not after 20, 25, 30 or 35 d of calcium deficiency. No consistent changes in the concentration of immunoreactive somatomedin C were observed during calcium restriction. In both the control and low calcium fed birds the plasma concentrations of GH were elevated by the intravenous administration of human pancreatic GH releasing factor (hpGRF) and by thyrotropin releasing hormone (TRH). The GH responses to these provocative stimuli were not reduced in magnitude by calcium deficiency. It is suggested, therefore, that the effect of calcium deprivation on the secretion of GH is mediated via the reduced release of stimulatory hypophysiotrophic factors from the hypothalamus.
Pharmacological alterations in calcium status also suggest that calcium deprivation inhibits GH secretion. Plasma concentrations of GH were acutely depressed in young chicks following the administration of a calcium chelator (ethylene diaminotetraacetic acid) a calcium channel blocker (verapamil) and after calmodulin inhibition (by chlordiazapine and trifluorpenazine administration). These data therefore demonstrate the importance of calcium in the stimulation of GH secretion in the domestic fowl. 相似文献
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O. Alberto Chiesa Jurgen von Bredow Hui Li Michelle Smith 《Canadian journal of veterinary research》2009,73(1):42-48
The purpose of the current study was to investigate the suitability of an isobaric laparoscopic procedure, using a single port, for obtaining serial kidney and liver biopsy samples from standing steers. The samples were used in support of a pharmacokinetic tissue–fluid correlation study. Laparoscopic access was performed 3 times in each of 8 healthy Holstein steers, alternating from the right side to the left side and then to the right side again. The surgery was performed in standing stocks after the animals were given 3 doses of sulfadimethoxine sulfate intravenously and fasted for at least 18 h. Sedation and analgesia were achieved with acepromazine and xylazine. Lidocaine 2% was injected at the center of the paralumbar fossa (left or right), and an incision was made for introduction of a trocar–cannula assembly. Room air was allowed to enter the abdomen through the cannula at the time of insertion. Once the peritoneal cavity was reached, an operating endoscope was inserted. No pressurized insufflation was performed. A biopsy forceps was introduced into the operating channel of the endoscope to obtain a 100-mg kidney or liver sample. No complications were encountered. The 24 laparoscopic procedures provided 24 kidney and 16 liver samples. The results suggest that the isobaric (gasless) single-port laparoscopic technique is feasible for kidney and liver biopsy on standing steers. The procedure can be performed in a reliable and efficient manner in the sedated standing bovine. 相似文献
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LUO Hong-yan TANG Ming DU Yi-mei LIU Chang-jin TANG Bi HU Xin-wu HU Mou-xian XI Jiao-ya SONG Yuan-long Jurgen Hescheler 《园艺学报》2006,22(11):2098-2101
AIM:To determine the effect of hydrogen peroxide (H2O2) on voltage-gated potassium channel currents (IKv) in pulmonary vascular smooth muscle cells (PASMCs). METHODS:Using whole cell patch-clamp technique, IKv was recorded in freshly isolated rat PASMCs with acute enzymatic digestion method. The effect of hydrogen peroxide on IKv in PASMCs was investigated in normoxia. RESULTS:IKv in PASMCs was increased significantly by H2O2 and the increase depended on the concentration in normoxia. Current-voltage relationship curve shifted to the left. CONCLUSION:Hydrogen peroxide is an important K+ channel opener. 相似文献
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呼吸道疾病可造成严重的经济损失,对受害鸡群的治疗常常很成问题。因此,对呼吸道疾病的临床症状,诊断方法、预防方法以及治疗都必须 有充分的了解,本叙述了非病毒性鸡呼吸道疾病。 相似文献
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Jurgen Schultze-Motel Reinhard Fritsch Karl Hammer Peter Hanelt Joachim Kruse Helga I. Maass Harald Ohle Klaus Pistrick 《Genetic Resources and Crop Evolution》1984,32(4):245-259
Summary Important papers on taxonomy and evolution of cultivated plants published in 1982 and 1983 were compiled and briefly discussed.
Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1982/1983
Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1982 und 1983 wurden zusammengestellt und kurz kommentiert.
: 1982–1983
, 1982 1983 . .相似文献
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