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101.
To establish the functional nature of the anatomically demonstrated main olfactory bulb inputs to the supraoptic nucleus, electrophysiological responses of intracellularly recorded supraoptic neurons to lateral olfactory tract stimulation were recorded in horizontal slices of basal forebrain and hypothalamus. A total of 71 synaptically influenced neurons were studied in slices from adult rats of both sexes. Of these, 60 cells (84%) were monosynaptically activated by olfactory tract stimulation; seven cells (10%) were activated via polysynaptic pathways; and four cells (6%) were characterized by long latency inhibitory responses. Lucifer Yellow was injected into 64 cells and subsequent immunocytochemical identification of 44 of these neurons showed that both oxytocin and vasopressin cells, in approximately equal numbers, were excited by olfactory stimulation. Polysynaptically mediated excitation, however, was only associated with oxytocin cells (six of the six identified cells). These results corroborate anatomical tract tracing data showing main olfactory bulb efferents to both supraotic neurons and to neurons of the perinuclear zone. Also supported are earlier speculations of olfactory participation in release of oxytocin and vasopressin during various physiological states. 相似文献
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Leonora Q. Schwandt Henri-Jacques Tjong-Ayong Ranny van Weissenbruch Henny C. der Mei Frans W. J. Albers 《European archives of oto-rhino-laryngology》2006,263(6):518-523
Tracheoesophageal voice prostheses need to be replaced due to increased airflow resistance or retrograde leakage of fluid into the trachea as a consequence of biofilm formation. Previous in vitro studies show a change of aerodynamic features of biofilm covered voice prostheses after removal of the prostheses out of the patient. To assess these changes in an in situ situation, aerodynamic characteristics were measured within 45 patients at the beginning and at the end of the wearing process of the Provox 2 voice prosthesis. As a consequence, the influence of biofilm formation on aerodynamic characteristics can be evaluated. In the majority of cases, leakage through the prosthesis was the reason for replacement. No differences were found in the total flow, volume range and intratracheal pressure (ITP) of the voice prostheses measured. The airflow resistance of biofilm covered prostheses was significantly reduced compared to new clean prostheses. However, no correlation was found between the extent of biofilm and the different aerodynamic features measured. Biofilm formation on the Provox 2 is responsible for both reduction in airflow resistance and leakage through the prosthesis by deterioration of the silicone rubber material. 相似文献
104.
Lou Zhong-jin罗仲金 Wang Ling王玲 Liu Qing 刘庆Tian Guang-zhao田光兆 Hu Xiao-su胡孝素 Huang Guang-qi黄光琦Qian Fang钱方 Ran Rui-tu冉瑞图West China University of Medical Sciences ChengduHuang De-huai黄德淮Chengdu Fifth People''s Hospital Chengdu 《中华医学杂志(英文版)》1987,100(9):740-744
Comparative studies are made on the relative
percentages of amino acid content and LDH isozyme
by electrophoresis and Slab-PAGE in adult worms
of Ascaris lumbricoides, Ascaris suum and Toxocara
canis. The results show that there are remarkable
differences of Arg and His of 17 amino acids bet.
ween Toxocara canis and human intestinal ascaris,
human biliary ascaris and pig ascaris; there are also
obvious differences of band positions of LDH
isozyme electrophoretic patterns and band position
and amount of slab-PAGE patterns among them,
whereas no marked differences are found in these
three indices in human intestinal ascaris, human
biliary ascaris and pig ascaris. 相似文献
105.
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108.
黄芪、雷公藤多甙对大鼠肾小球系膜细胞分泌IL-6的影响 总被引:3,自引:0,他引:3
目的:观察黄芪和雷公藤多甙对大鼠肾小球系膜细胞分泌IL-6水平的影响.方法:应用细胞培养技术进行肾小球系膜细胞培养,采用血清药理学方法,制备黄芪药物血清,雷公藤多甙药物血清,并分为低、中、高3个剂量梯度,观察药物血清对正常状态下肾小球系膜细胞分泌IL-6的影响,采用细胞ELISA法测定IL-6含量.结果:黄芪、雷公藤多甙各不同剂量组均可抑制肾小球系膜细胞产生IL-6,其抑制作用随剂量增加而增殖,其中尤以雷公藤高剂量组、中剂量组及黄芪高剂量组作用明显.结论:黄芪可抑制肾小球系膜细胞分泌IL-6,这一作用与雷公藤类似.这可能是黄芪防治肾小球硬化的作用机制之一. 相似文献
109.
110.