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991.
Chen ZM Sandercock P Pan HC Counsell C Collins R Liu LS Xie JX Warlow C Peto R 《Stroke; a journal of cerebral circulation》2000,31(6):1240-1249
BACKGROUND AND PURPOSE: Long-term daily aspirin is of benefit in the years after ischemic stroke, and 2 large randomized trials (the Chinese Acute Stroke Trial [CAST] and the International Stroke Trial [IST]), with 20 000 patients in each, have shown that starting daily aspirin promptly in patients with suspected acute ischemic stroke also reduces the immediate risk of further stroke or death in hospital and the overall risk of death or dependency. However, some uncertainty remains about the effects of early aspirin in particular categories of patient with acute stroke. METHODS: To assess the balance of benefits and risks of aspirin in particular categories of patient with acute stroke (eg, the elderly, those without a CT scan, or those with atrial fibrillation), a prospectively planned meta-analysis is presented of the data from 40 000 individual patients from both trials on events that occurred in the hospital during the scheduled treatment period (4 weeks in CAST, 2 weeks in IST), with 10 characteristics used to define 28 subgroups. This represents 99% of the worldwide evidence from randomized trials. RESULTS: There was a highly significant reduction of 7 per 1000 (SD 1) in recurrent ischemic stroke (320 [1.6%] aspirin versus 457 [2. 3%] control, 2P<0.000001) and a less clearly significant reduction of 4 (SD 2) per 1000 in death without further stroke (5.0% versus 5. 4%, 2P=0.05). Against these benefits, there was an increase of 2 (SD 1) per 1000 in hemorrhagic stroke or hemorrhagic transformation of the original infarct (1.0% versus 0.8%, 2P=0.07) and no apparent effect on further stroke of unknown cause (0.9% versus 0.9%). In total, therefore, there was a net decrease of 9 (SD 3) per 1000 in the overall risk of further stroke or death in hospital (8.2% versus 9.1%, 2P=0.001). For the reduction of one third in recurrent ischemic stroke, subgroup-specific analyses found no significant heterogeneity of the proportional benefit of aspirin (chi(2)(18)=20. 9, NS), even though the overall treatment effect (chi(2)(1)=24.8, 2P<0.000001) was sufficiently large for such subgroup analyses to be statistically informative. The absolute risk among control patients was similar in all 28 subgroups, so the absolute reduction of approximately 7 per 1000 in recurrent ischemic stroke does not differ substantially with respect to age, sex, level of consciousness, atrial fibrillation, CT findings, blood pressure, stroke subtype, or concomitant heparin use. There was no good evidence that the apparent decrease of approximately 4 per 1000 in death without further stroke was reversed in any subgroup or that in any subgroup the increase in hemorrhagic stroke was much larger than the overall average of approximately 2 per 1000. Finally, there was no significant heterogeneity between the reductions in the composite outcome of any further stroke or death (chi(2)(18)=16.5, NS). Among the 9000 patients (22%) randomized without a prior CT scan, aspirin appeared to be of net benefit with no unusual excess of hemorrhagic stroke; moreover, even among the 800 (2%) who had inadvertently been randomized after a hemorrhagic stroke, there was no evidence of net hazard (further stroke or death, 63 aspirin versus 67 control). CONCLUSIONS: Early aspirin is of benefit for a wide range of patients, and its prompt use should be routinely considered for all patients with suspected acute ischemic stroke, mainly to reduce the risk of early recurrence. 相似文献
992.
The present study examined possible parallels between the structure of human visuospatial abilities and the organization of the neural systems. Forty-eight participants were tested on seven speeded visuospatial tasks. Three of these tasks were constructed so as to rely primarily on known ventral stream functions and four were constructed so as to rely primarily on known dorsal stream functions. Both sets of tasks spanned approximately the same range of difficulty as indexed by both the speed and accuracy of decision making. Factor analysis of response times on the seven tasks revealed only two significant factors. The putative ventral stream tasks all loaded heavily on one factor (mean loading=0.843) but only weakly on the other factor (mean loading=0.222); the putative dorsal stream tasks showed the opposite pattern in that they all loaded heavily on the second factor (mean loading=0.828) but only weakly on the first factor (mean loading=0.229). These findings are consistent with the hypothesis that human visuospatial abilities can be classified using categories based on the specializations of underlying neural structures and systems. 相似文献
993.
Scorpion alpha and alpha-like toxins differentially interact with sodium channels in mammalian CNS and periphery 总被引:2,自引:0,他引:2
Gilles N Chen H Wilson H Le Gall F Montoya G Molgo J Schönherr R Nicholson G Heinemann SH Gordon D 《The European journal of neuroscience》2000,12(8):2823-2832
Scorpion alpha-toxins from Leiurus quinquestriatus hebraeus, LqhII and LqhIII, are similarly toxic to mice when administered by a subcutaneous route, but in mouse brain LqhII is 25-fold more toxic. Examination of the two toxins effects in central nervous system (CNS), peripheral preparations and expressed sodium channels revealed the basis for their differential toxicity. In rat brain synaptosomes, LqhII binds with high affinity, whereas LqhIII competes only at high concentration for LqhII-binding sites in a voltage-dependent manner. LqhII strongly inhibits sodium current inactivation of brain rBII subtype expressed in HEK293 cells, whereas LqhIII is weakly active at 2 microM, suggesting that LqhIII affects sodium channel subtypes other than rBII in the brain. In the periphery, both toxins inhibit tetrodotoxin-sensitive sodium current inactivation in dorsal root ganglion neurons, and are strongly active directly on the muscle and on expressed muI channels. Only LqhII, however, induced repetitive end-plate potentials in mouse phrenic nerve-hemidiaphragm muscle preparation by direct effect on the motor nerve. Thus, rBII and sodium channel subtypes expressed in peripheral nervous system (PNS) serve as the main targets for LqhII but are mostly not sensitive to LqhIII. Toxicity of both toxins in periphery may be attributed to the direct effect on muscle. Our data elucidate, for the first time, how different toxins affect mammalian central and peripheral excitable cells, and reveal unexpected subtype specificity of toxins that interact with receptor site 3. 相似文献
994.
Association analysis of the GABA(A) receptor subunit genes cluster on 5q33-34 and alcohol dependence in a Japanese population 总被引:4,自引:0,他引:4
Recent investigations suggest that genetic susceptibility to alcohol dependence may be conferred by GABA(A) receptor subunit genes. In this study, three RFLPs at the GABA(A)beta2, GABAAalpha6, GABA(A)alpha1 and two at the GABA(A)gamma2 receptor subunit genes, were examined for association with alcohol dependence in 189 subjects meeting DSM-III-R criteria for this disorder and 152 unrelated controls from a Japanese population. The results demonstrated no association between the AlwNI RFLP at the GABA(A)alpha6 receptor subunit gene and alcohol dependence (P = 0.059). However, the NciI RFLP at the GABA(A)gamma2 receptor subunit gene was associated with alcohol dependence comorbid with antisocial personality disorder (P = 0.021). This supports a recent finding reporting an association between the GABA(A)gamma2 receptor subunit gene and alcohol dependence with criminal record in a Finnish population. Taking into account the effects of multiple comparisons, this result should be interpreted with caution pending replication. 相似文献
995.
目的 评价电超导辅助治疗小儿肺炎的临床疗效。方法 所有144例,治疗组84例,对照组64例,对照组应用抗生素,同时止咳,化痰,平喘对症处理,治疗组在以照组的基础上超导辅助治疗,疗程一周。结果 治疗组总有效率100%,总痊愈率92.86%。而对照组总有效率仅为71.67%。结论 在原有治疗基础上加用电超导,可明显提高治愈率及总有效率。 相似文献
996.
997.
DNA测序建立甘肃当归、大黄种子rRNA基因图谱的研究 总被引:3,自引:0,他引:3
目的:对甘肃地道性中药材当归、大黄种子中rRNA基因内转录间隔区进行碱基序列测定,以期建立从分子水平对中草药种子进行鉴定的一种新方法。方法:提取当归、大黄种子中核DNA,利用特异性引物对其rRNA基因内转录间隔区进行套式PCR扩增,并将扩增产物进行碱基序列测定。结果:经琼脂糖凝胶电泳证实:以上述方法可获得当归、大黄种子DNA中rRNA基因内转录间隔区PCR扩增产物;并经测序后得到了当归、大黄种子rRNA基因内转录间隔区的碱基序列,且具有明显的差异和可对比性。结论:不同植物性中药材种子rRNA基因内转录间隔区碱基序列可做为从分子水平进行鉴定的标记。 相似文献
998.
鹿茸口服液促进RNA和蛋白质合成作用的研究 总被引:1,自引:0,他引:1
目的:研究鹿茸口服液对青年及老年小鼠RNA和蛋白质合成的作用。方法:观察口服鹿茸口服液对小鼠肝RNA和蛋白质含量及^3H-Uridine和^3H-Leucine掺入的影响。结果:鹿茸口服液可明显增加老年小鼠肝RNA和蛋白质含量及[^3H]Uridine和[^3H]Leucine掺入RNA和蛋白质,作用明显强于青年小鼠。结论:鹿茸口服液对老年小鼠RNA和蛋白质合成有明显促进作用。 相似文献
999.
引入市场机制,采取分权、分级与分类管理等政策与措施是当今国际卫生体制改革中的主流特点,由于各个国家的社会经济体制与卫生保健制度不同,这些改革政策与措施所产生的影响与效果也各具特色.因此,在深化我国卫生体制改革的进程中,借鉴国际卫生体制改革的经验与教训具有一定的现实意义. 相似文献
1000.