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181.
H. V. Carey H. J. Cooke P. R. Nemeth D. H. Zafirov J. D. Wood 《Cellular and molecular life sciences : CMLS》1985,41(9):1156-1158
Summary The effects of forskolin on myenteric neuronal activity and mucosal function were examined in guinea pig ileum. Forskolin increased the excitability of myenteric neurons, and increased mucosal chloride secretion by stimulating enteric neurons as well as by acting directly on enterocytes.Acknowledgment. The authors thank E. Martens, S. Bowen for technical assistance and N. Schaad for secretarial assistance. This work was supported by National Institutes of Health Grants, F32-AM07301, K-104-AM1004, RO1-AM29699, RO1-AM26742 and an Eloise Gerry Fellowship. 相似文献
182.
Summary In the normal Wistar rat, the plasma -MSH level was raised by hypertonic saline injection (as compared with control rats injected with isotonic saline). No such rise in -MSH followed hypertonic saline administration in the Brattleboro (hereditary diabetes insipidus) animal (compared to isotonic saline injected controls). It is suggested that, in the rat, endogenous antidiuretic hormone is involved in the secretory response of the pars intermedia to osmotic stimuli. 相似文献
183.
R. H. Scheffrahn J. J. Sims L. K. Gaston M. K. Rust 《Cellular and molecular life sciences : CMLS》1984,40(10):1136-1137
Summary The soldier cephalic secretion of the Nearctic desert termite,Amitermes minimus, consists almost entirely of 4,11-epoxy-cis-eudesmane which was previously identified from soldiers of 2 AfricanAmitermes species. Soldiers ofA. minimus each store circa 61 g of the secretion. Bioassays with the ant,Crematogaster californica, indicate a repellent role for the eudesmane compound in termite defense.Classification as proposed by Sands, W.A., Bull. Br. Mus. nat. Hist., Ent., suppl.18 (1972).Supported by Sigma Xi Grant-in-Aid of Research and California Statewide Critical Applied Research grant. 相似文献
184.
To study the effect of a sudden loss of body weight on the -cell function of aging rats, basal and glucose-induced insulin secretion was measured in pancreatic islets obtained from young (2-month-old), adult (12-month-old) and aging (24-month-old) rats, either fed ad libitum or fed a restricted diet (50% caloric restriction). Basal insulin secretion was similar in islets of young, adult and older rats. Glucose stimulated insulin release was significantly reduced in aging rats as compared to young animals. Animals fed a restricted diet showed a prolonged and higher secretory rate during first phase release when compared to animals fed ad libitum. 相似文献
185.
采用放射免疫分析测定技术,研究了脱水穿心莲内酯丁二酸单酯钠盐制剂对体外培养的人绒毛组织激素分泌的影响,并应用透射电镜技术,从超微结构的水平上观察分析了穿心莲制剂组织特异性细胞毒效应,发现这种穿心莲制剂能特异性破坏绒毛合体滋养层细胞结构,包括蛋白质的合成系统,使hCG的合成受影响。用放射免疫法测定培养液中的hCG,以确定该激素的合成与分泌状态,结果发现,穿心莲制剂处理的实验组,hCG的合成和分泌明显受阻,与对照组差异显著。超微结构观察表明,穿心莲制剂的细胞毒作用是组织特异性和剂量依赖性的,特异地作用于绒毛的合体滋养层细胞而对细胞滋养层及间质组织均无损伤。 相似文献
186.
目的 :探讨螺旋CT双期增强扫描诊断胰腺癌的价值。方法 :16例胰腺癌患者行螺旋CT双期增强扫描 ,动脉期延迟 2 5s,门静脉期延迟 60s ,以 3mL/s团注造影剂 80~ 10 0mL。测量肿瘤和正常胰腺组织的CT值 ,计算肿瘤 -胰腺密度差 ,同时对胰腺周围血管进行观察评价。结果 :肿瘤的平均CT值动脉期和门静脉期分别为 (4 7± 8)HU、(5 3± 10 )HU ;正常胰腺动脉期和门静脉期的CT值分别为 (10 9± 16)HU ,(76± 13)HU ;肿瘤 -胰腺密度差动脉期和门静脉期各为 (70± 18)、(2 3± 12 )HU ,二者差异明显 (P <0 0 1)。胰周动脉侵犯在动脉期显示好 ,静脉侵犯在门静脉期显示好。结论 :螺旋CT双期增强扫描动脉期可获得最大的肿瘤 -胰腺密度差 ,动脉期结合门静脉期对胰周血管侵犯的评价更全面 ,提高了胰腺癌手术可切除性评价的准确性。 相似文献
187.
扬子鳄臭腺腺细胞分泌颗粒的电镜观察 总被引:1,自引:0,他引:1
用透射电镜观察了扬子鳄两种臭腺即下颌腺和泄殖腔腺腺细胞的分泌颗粒.结果表明,下颌腺腺细胞产生两种分泌颗粒,泄殖腔腺腺细胞产生四种分泌颗粒.本文还对扬子鳄两种臭腺的生理功能进行了讨论. 相似文献
188.
Summary Casein and lactose concentrations in milks of various species vary by at least 1–2 orders of magnitude, yet no single species secretes both components at either the high or the low end of the ranges. This pattern of variation could result from evolutionary adaptations in a single secretory mechanism. 相似文献
189.
T. A. Chatterton C. H. Reynolds N. R. Lazarus C. I. Pogson 《Cellular and molecular life sciences : CMLS》1984,40(12):1426-1427
Summary Incubation of rat islets with phenylalanine increased the tissue content of phosophoenolpyruvate, both in the presence and in the absence of glucose. At the same time, L-phenylalanine neither stimulated nor inhibited insulin release. It is unlikely that insulin secretion is tightly coupled to the availability of phosphoenolpyruvate in rat islets. 相似文献
190.
将含有αA干扰素基因的DNA片段接上化学合成的EcoR I-Hind III转换接头,然后插入酵母分泌型表达载体YFD 18中,构建成质粒YFD 66和YFD66-0.转化酵母菌BJl991后,得到转化子BJ1991/YFD66和BJl991/YFD66-0.干扰素活性测定表明,每升BJ1991/YFD66培养液含有αA干扰素10~6U,而BJ1991/YFD66-0则不产生干扰素,YFD66为αA干扰素表达质粒。 相似文献