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71.
An impairment of prefrontal cortical functioning in schizophrenia ('hypofrontality') has been suggested by clinical, neuroimaging, and postmortem brain tissue studies. We used Western immunoblot and Northern hybridization analyses of postmortem brain tissue obtained from 14 schizophrenic patients and 12 control patients of similar ages to measure tissue levels of synaptophysin (a structural synaptic vesicle protein) and of SNAP-25 (a 25-kDa presynaptic protein), and their encoding mRNAs, in Brodmann's area 10 of prefrontal cortex. There were significant decreases in tissue levels of both of these proteins in prefrontal cortex of schizophrenic patients relative to controls. In contrast, tissue levels for the mRNAs encoding these proteins were not decreased in schizophrenic patients. Subsequent labeling of the same Western immunoblots showed no difference in tissue levels of glial fibrillary acidic protein (GFAP) in schizophrenic and control patients. Similarly, subsequent hybridization of the same Northern hybridization membranes showed no difference in tissue levels of GFAP mRNA or of 28S rRNA in schizophrenic and control patients. These alterations in tissue levels of synaptophysin and SNAP-25 are consistent with the idea that the clinically observed 'hypofrontality' of schizophrenia arises from abnormalities of synaptic number or structural integrity in prefrontal cortex.  相似文献   
72.
This study examined the effect of a pharmacologically induced rightward shift in the partial pressure of oxygen at which 50% of hemoglobin is saturated (P50) on outcome from transient focal cerebral ischemia in the rat. Halothane anesthetized rats (n=20 per group) were given saline or a single 15-min infusion of 150 mg/kg RSR13 (2-[4-[[3,5-dimethylanilino) carbonyl]methyl]phenoxy]-2-methylproprionic acid) intravenously before or 30 min after onset of 75 min of middle cerebral artery filament occlusion (MCAO). Seven days later, severity of hemiparesis and cerebral infarct size were examined. RSR13 alone did not significantly improve outcome. Conscious normothermic rats (n=12 per group) were also given RSR13 (150 mg/kg) or 0.9% NaCl intravenously and subjected to 75 min of MCAO with 7 days of recovery. Again, RSR13 alone did not significantly reduce infarct size or improve neurologic score. A dose-response curve for dizocilpine (MK-801) was then constructed in conscious normothermic rats subjected to 75 min of MCAO. Dizocilpine (0.5 mg/kg i.v.) caused a 90% reduction in mean infarct size while 0.25 mg/kg reduced infarct size by 48%. Other rats were then subjected to 75 min of MCAO after being given dizocilpine (0.25 mg/kg i.v.; n=18) or RSR13 (150 mg/kg i.v. )+dizocilpine (0.25 mg/kg i.v.; n=15). RSR13+dizocilpine resulted in smaller cortical infarct volume (8+/-14 mm3 vs. 34+/-37 mm3, p<0.02) and total cerebral infarct volume (46+/-28 mm3 vs. 81+/-60 mm3, p<0. 05) compared to dizocilpine alone, respectively. We conclude that a pre-ischemic peak increase in P50 of approximately 25 mmHg alone is insufficient to reduce focal ischemic injury, but may be advantageous when used in conjunction with other neuroprotective agents.  相似文献   
73.
Mechanism of action of amiloride: a molecular prospective   总被引:1,自引:0,他引:1  
Amiloride is a prototypic inhibitor of epithelial sodium channels. Rapid progress has been made in our understanding of the structure of the sodium channel and related cation-selective channels. This work, coupled with experiments examining how selected sodium channel mutations affect amiloride binding, provides critical clues towards defining sites within the channel that bind amiloride. Residues within the channel pore and within its extracellular domain participate in amiloride binding. These results suggest that sites that interact with amiloride within the channel's extracellular domain may be in close proximity to residues within the channel's pore.  相似文献   
74.
我国烧伤外科的进展与展望   总被引:4,自引:0,他引:4  
Guo Z  Sheng Z 《中华外科杂志》1999,37(10):598-601
一、烧伤外科光辉的41年与兄弟学科相比,烧伤外科起步相对较晚,刚刚度过“不惑之年”。虽然学科年轻,但发展迅速,临床治疗达到世界领先水平,基础研究亦跻身于世界先进行列。我国烧伤专业的发展大体经历了三个阶段[1]。1958年由于土法上马全民大炼钢铁,致使烧伤患者骤然增多。北京、上海、重庆、西安等大城市率先在几个大医院成立了烧伤专科。上海瑞金医院成功地救治了烧伤面积89%,Ⅲ度烧伤23%的钢铁工人邱财康。这一史无前例的医学奇迹,震惊了世界,也鼓舞了国人。进入60年代全国各地先后成立了烧伤科或组建了烧伤…  相似文献   
75.
目的 对111眼屈光范围球镜在-3.00 ̄-17.00D及柱镜在-0.50D ̄-4.50D范围的患者进行了PRK术后的分析。方法 采用美国VISX20/20B准分子激光系统的最新软件包进行角膜切削,并行术前后的主客观验光及角膜透明度检查。结果与结论 准分子激光PRK术是目前理想的屈光手术之一,特别对于中低度近视尤为适合,对高度近视则其预见性稳定性较差,并发症的发生并未成为影响术后效果的主要因素。  相似文献   
76.
Mercury vapor sorption by soil increased curvilinearly with the increase of soil moisture content until a maximum was reached. A further increase of moisture content caused a decline in mercury sorption. The percent moisture contents which gave maximal increase of203Hg vapor sorption in these soils coincide quite closely with their water-holding capacity values at 1/3 bar.Soil microorganisms may play a part in moist soil for the increase of elemental mercury vapor sorption and subsequent transformation to mercuric form.Mercury vapor diffused into both dry and moist soil columns and the diffusion profile can be described by an exponential function of the form, y=ae–bx, where a is the adsorption characteristics of the soil, b is the diffusivity coefficient and x is the depth of soil. The diffusivity coefficient for mercury vapor varied with the soil type and its moisture content.Supported in part by grant R-803948 from the U.S. Environmental Protection Agency. Technical Paper No. 5489, Oregon Agricultural Experiment Station.  相似文献   
77.
Biochemical and metabolic indicators were monitored in a group of volunteers suffering from a variety of chronic illnesses participating in a week's course on a special uncooked vegetable diet, known as "living food". Unmatched healthy controls ate the same diet cooked for 2 min in a microwave oven. After 1 week on the regimen, serum protein and urea contents decreased and alanine aminotransferase (ALAT) activity increased in both groups, although all within the normal range. Blood glucose increased in both groups to slightly above normal limits but total serum cholesterol dropped about 1 mmol/l from normal starting levels. Serum tocopherol and retinol increased only in the group eating the uncooked diet. In both groups urinary sodium dropped drastically without a significant change in potassium. Serum and urinary phenol and p-cresol diminished also significantly. It is concluded that this vegetable diet may be of some benefit in the short term but any longer-term use requires evaluation.  相似文献   
78.
第二信使系统和其介导的基因表达对针灸效应影响的研究   总被引:2,自引:0,他引:2  
从微观水平研究针灸效应对揭示其机理有重要的意义。本文从第二信使系统和其介导的基因表达对针灸效应影响的研究方面综述了针灸效应的终结反映于细胞内生物效应的变化(即对机体不同器官组织细胞内的物质代谢调节 ) ,从一个侧面提示 ,针灸对机体各系统的调节作用最终是在细胞通过胞内信息传导系统实现的  相似文献   
79.
六味地黄汤含药血清对海马神经元突触活动的影响   总被引:3,自引:1,他引:3  
目的:研究六味地黄汤益智作用的机理。方法:应用血清药理学和电生理方法,观察六味地黄汤含药血清对原代培养大鼠海马神经元自发突触活动的影响。结果:含药血清作用48h可明显增加海马神经元自发动作电流(spontaneous action cur-rent,sAC)和微小兴奋性突触后电流(miniature excitatory post aynaptic currenl,mEPSC)的产生频率,但并不影响mEPSC的幅度。结论:六味地黄汤可作用于突触前位点对海马神经元突触活动产生调节作用,该作用可能是其调节海马神经元的兴奋性进而发挥益智作用的机制之一。  相似文献   
80.
辨证分期治疗慢性盆腔炎合并免疫性不孕症18例疗效观察   总被引:1,自引:0,他引:1  
叶敦敏  邱淑丽  赵颖 《新中医》2003,35(5):22-23
目的:探讨辨证分期治疗慢性盆腔炎合并免疫性不孕症的临床疗效。方法:选择慢性盆腔炎合并免疫性不孕症(血清抗精子抗体阳性)患者18例,采用辨证分期治疗。月经干净后,治以活血化瘀、理气祛湿为主;在(或相当于)排卵期或排卵后,治以补肾养血,活血化瘀为主;在经前期,治以理气活血调经为主;在月经干净后至经前期,加用小剂量阿司匹林。结果:盆腔炎临床症状及体征痊愈7例,显效6例,有效5例;全部患者获得妊娠,宫内妊娠者17例(观察至妊娠3月,均正常),输卵管妊娠1例;结论:中医辨病辨证结合的周期疗法加小剂量阿司匹林治疗慢性盆腔灸合并免疫性不孕症有一定的疗效。  相似文献   
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