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81.
The blocking effects of d-diltiazem, its metabolites, deacetyl-d-diltiazem (d-M1), deacetyl-N-demethyl-d-diltiazem (d-M2), deacetyl-O-demethyl-d-diltiazem (d-M4) and deacetyl-N, O-demethyl-d-diltiazem (d-M6) and 1-diltiazem were investigated on the voltage-gated calcium current (ICa) of an Achatina neurone. Based on the IC50 values, the order of potency was: d-diltiazem (0.426 mM), d-M2 (0.456), d-M1 (0.491), 1-diltiazem (0.759) greater than d-M4 (1.212) greater than d-M6 (greater than 2.000). Assuming that the IC50 reflects the KD for resting Ca2+ channels (Kr), steady state activation studies gave KD values for the inactivated channels (Ki) and Kr/Ki ratios of 0.122 mM (Ki) and 3.52 (Kr/Ki) (d-diltiazem), 0.112 and 6.98 (1-diltiazem), 0.083 and 6.07 (d-M1) and 0.156 and 2.97 (d-M2). All drugs tested showed a certain degree of voltage-dependence. The further percentage reduction in the normalized ICa after high frequency stimulation demonstrated the use-dependence of: 1-diltiazem (27.5%), d-diltiazem (26.3) greater than d-M2 (19.2) greater than d-M1 (16.7) greater than d-M6 (9.8). The voltage- and use-dependence of these drugs are consistent with their Ca2+ antagonistic properties.  相似文献   
82.
孙世荣  孙晓庆 《河北医学》1996,2(4):299-301
在山羊MODS的模型上,观察了血浆TNF与MODS的关系,32只山羊分为三组:失血性休克组(H);门静脉毒素血症组(E);失血性休克+内毒素血症组(M)。结果表明,三组动物血浆TNF均见升高,M组最明显。动物死亡率及MODS的发生率也是M组最高。可以认为TNF持续升高导致MOD发生发展的重要因素之一。  相似文献   
83.
A tissue equivalent phantom was used in the study and absored x-ray doses.It measuring for some important organs of head and neck by four routive sialography methods (panoramic conventional x-ray radioagraphy,tomography,fluoroscope,CT) and also the X-ray absorbed doses of thyroid and len when lead containing loop and spectacles of head containing glass were used for prevention.All the data were processed statistically and a compartive study of absorbed x-ray doses of four sialography methods:Doses of submandibular gland were higher in CT,tomography and fluoroscope among them,CT was the highest indicating that it was superior to other methods for accurately locating that it was superior to other methods for accurately locating the within-gland tumor.Fluoroscope will be use more frequently in clinic,because it can observe the living gland panoramic and normal radiography can be used routinely because they had the minimum doses in measured organs.2.The absorbed x-ray doses of len and thyroid decreased by 93%-% when prevention was taken in CT or fluoroscope,65%-85% doses was decreased in normal radiography or panoramic with prevention.  相似文献   
84.
为了探索单疱病毒性角膜炎的发病机制和快速诊断HSK。方法应用多聚酶链反应对感染的HSK的20只纯新西兰白兔和60例HSK患者的角膜进行了单疱病毒-1-DNA检测。结果急性感染期的5只兔角膜和12只人角膜均阳性;用稳定期45d的兔角供体行部分穿透性角膜移植术,术后50d10只兔角膜中7只阳性,稳定期6个月-6年的18只人角膜片,12只阳性;30例临床可疑HSK角膜刮取物,26例阳性;5只未感染HSK  相似文献   
85.
Chronic Ethanol Inhibits Inositol Metabolism in Specific Brain Regions   总被引:1,自引:0,他引:1  
Many neurotransmitters and hormones in the nervous system transmit signals through receptors coupled to the poly-phosphoinositide (PI) signaling pathway. In this study, an in vivo protocol with (3H]inositol was used to examine the effect of chronic ethanol administration on inositol metabolism and poly-PI turnover in the cerebral cortex, hippocampus, and cerebellum of mouse brain. C57BL/6 mice were given a nutritionally complete liquid diet containing either ethanol (5%, w/v) or isocaloric sucrose for 2 months. Mice were injected intracerebrally with rH]inositol; after 16 or 24 hr, they were injected intraperitoneally with lithium (8 mEq/kg body weight) to inhibit the inositol monophosphatase (IP1) activity. All mice were decapitated 4 hr after lithium injection. Labeled inositol phospholipids accounted for 16 to 23% of total labeled inositol in different regions of control mouse brain, and the percentages in the hippocampus were consistently higher than the cerebral cortex and cerebellum. In control mice, the percentages of labeled IP, after a 4-hr lithium treatment were 11.5%, 9.9%, and 3.7% for cerebral cortex, hippocampus, and cerebellum, respectively. Chronic ethanol feeding resulted in a significant (p < 0.05) decrease in the percent of labeled IP1 and inositol phospholipids, and this effect was observed in the cerebral cortex and, to a lesser extent, hippocampus but not cerebellum. When ratios of labeled IP1 were expressed against labeled inositol phospholipids as an index of the poly-PI turnover activity, significant decreases in IP/lipid ratios were observed in the cerebral cortex, but not the hippocampus or cerebellum. Although mice killed 24 + 4 hr after the last ethanol feeding would have experienced an 8-hr period of ethanol withdrawal, compared with the 16 + 4-hr group, no differences in IP/lipid ratios were observed between the two time groups. These results illustrate regional differences in the effect of chronic ethanol on inositol metabolism in the brain, but no difference in poly-PI turnover in brain due to ethanol withdrawal.  相似文献   
86.
选择性髂内动脉结扎与栓塞对盆腔血供的影响   总被引:5,自引:0,他引:5  
目的:旨在探讨选择性髂内动脉结扎与栓塞两种方法对盆腔血供的影响。方法:将两组犬在膀胱上动脉分支以下之髂内动脉分别行结扎与栓塞,对比观察两组膀胱创面出血、盆腔动脉造影及盆腔脏器组织学变化,以确定其盆腔脏器的血供情况。结果:①结扎组膀胱创面出血明显大于栓塞组;②结扎组髂内动脉侧支循环建立时间明显早于且数目多于栓塞组;③两组盆腔脏器均未见缺血坏死。结论:栓塞组阻断髂内动脉侧支循环的数目多于结扎组,故对盆腔血供的影响大于结扎组。避免髂内动脉阻断范围过广可减少盆腔脏器缺血坏死的机会。  相似文献   
87.
本文对食管癌高、低发区食管癌患者和正常人,经MNNG诱导的DNA损伤修复功能进行了研究。实验采用外周血淋巴细胞培养的方法。每组又分为对照组及MNNG诱导组。样品以~3H-TdR标记后经液闪仪计数法进行检测。结果发现,低发区正常人经MNNG诱导的DNA损伤修复功能明显高于对照组,两个地区食管癌患者修复能力均低于正常人,与地区无关。  相似文献   
88.
Summary. A prevalence study of Ureaplasma urealyticum (UU) infection of the male genital tract was carried out in Shanghai between March 1992 and June 1995. Significantly higher frequency of UU infection was found among infertile males (549/1416) as compared to fertile controls (34/375). Examination of 8 specimens each from infertile men and fertile subjects by electron microscopy, immunogold and immunofluorescence techniques, demonstrated adhesion of Ureaplasma urealyticum to the membrane of spermatozoa and exfoliated germ cells. In addition, gold particles on Ureaplasma urealyticum were found to be adhered to the sperm surface in 4 of the 8 samples. Strong specific anti-UU fluorescence was detected in 6 of 8 samples, mainly on the midpieces and post-acrosomal regions of the spermatozoa.
To further study the effects of Ureaplasma urealyticum on fertility, 47 male Sprague-Dawley (SD) rats were infected artificially with Ureaplasma urealyticum serotype 8 (T960). Morphological changes in the seminiferous tubules were observed 3–5 weeks after inoculation in the sacrificed animals. Dramatic impairment of spermatogenesis of both testes was found in 11 rats. Mating experiment confirmed infertility in 12 of 40 rats. Offsprings of the infected rats were significantly smaller than those of controls in terms of prenatal weights and birthweights.  相似文献   
89.
Most cases with recurrent parotitis in childhood (RPC) can be cured before puberty.1–3 A few of them, however, may continue to adulthood.1–4 To distinguish this condition from other types of chronic parotitis in adults, such as chronic obstructive parotitis,5 we suggest that the diagnosis of recurrent parotitis in adults (RPA) be reserved for the cases derived from RPC.6 The pathophysiology and development of RPA is still not well known. To our knowledge, there are few reports of RPA in the literature, especially concerning its histopathology. This report describes a cases of RPA studied with sialography and light and electron microscopy.  相似文献   
90.
本文报告了葡萄糖酸锌糖浆的制法及用二甲橙指示剂法测定含量的方法。结果表明制法简便,含量测定方法准确。  相似文献   
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