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41.
42.
本系统的107个电极中,103个分布于胸、背部,1个为参考电极,1个为V_3,其余用于肢导。本系统除能绘出2、4、8ms任意间隔的103通道同步的体表等电位图,常规12导联和V_(7 9)心电图,胸、背部位的心电图外,还可记录R峰值等电位图,∑R,Q波等电位图,nQ30、40,极大、极小轨迹图等。  相似文献   
43.
Heterogeneity among the spinocerebellar ataxias (SCA) has been shown on clinical, biochemical, and genetic criteria. Among the autosomal dominant SCAs, several kindreds have shown loose linkage to the HLA loci on chromosome 6, while linkage in other kindreds has been rejected. The advent of multipoint linkage analysis allows the use of several marker loci simultaneously, thus increasing the amount of usable information. We have reanalyzed linkage data from a large kindred with SCA and provide evidence for a telomeric location of the SCA gene in this family. Knowledge of the relative gene location will ease the identification of the SCA gene by reducing the size of the chromosomal regions that must be examined.  相似文献   
44.
医学生营养知识与膳食状况调查   总被引:7,自引:1,他引:6  
①目的了解医学生营养知识的掌握情况及对教育传播方式的需求意见,以加强营养知识教育,改善大学生的健康素质。②方法对762名在校大学生进行问卷调查。③结果医学院在校生对营养知识及常识掌握深度和广度都不够,但渴求得到营养知识的欲望比较高,对营养知识的重要性认识正确。有73.6%的学生认为营养知识对生活很重要。87.2%的学生愿意接受营养知识的教育,对营养知识教育的传播方式也表现出特有的需求意向。大学生的膳食结构不够合理,奶类、薯类、鱼虾禽类、豆制品摄入不足。④结论应加强医学生营养知识教育,使医学生做到科学合理的安排膳食,改善饮食行为,促进身体健康。  相似文献   
45.
本文采用高效液相色谱法分析研究了进口药品脑活素注射液中的氨基酸含量及其低分子肽的肽图。试验结果反映了该药品的内在质量,同时提出控制质量的可靠方法.  相似文献   
46.
A 15-year-old boy with a terminal deletion of the short arm of chromosome 4 is described. The patient has a mild clinical phenotype that is incompatible with Wolf-Hirschhorn syndrome. Careful neurological examination including CT scan did not show any signs of Huntington disease. The chromosomal breakpoint was analyzed by means of polymorphic DNA probes localized close to the tentative Huntington (HD) locus. The breakage has occurred between D4S43 and D4S90 loci and thus deletes part of the chromosomal candidate regions for the HD locus. © 1992 Wiley-Liss, Inc.  相似文献   
47.
Perfusion is a crucial physiological parameter for tissue function. To obtain perfusion-weighted images and consequently to measure cerebral blood flow (CBF), a newly developed flow-sensitive alternating inversion recovery (FAIR) technique was used. Dependency of FAIR signal on inversion times (TI) was examined; signal is predominantly located in large vessels at short TI, whereas it is diffused into gray matter areas at longer TI. CBF of gray matter areas in the human brain is 71 ± 15 SD ml/100 g/min (n = 6). In fMRI studies, micro- and macrovessel inflow contributions can be obtained by adjusting TIs. Signal changes in large vessel areas including the scalp were seen during finger opposition at a TI of 0.4 s; however, these were not observed at a longer TI of 1.4 s. To compare with commonly used BOLD and slice selective inversion recovery techniques, FAIR and BOLD images were acquired at the same time during unilateral finger opposition. Generally, activation sites determined by three techniques are consistent. However, activation of some areas can be detected only by FAIR, not by BOLD, suggesting that the oxygen consumption increase couples with the CBF change completely. Relative and absolute CBF changes in the contralateral motor cortex are 53 ± 17% SD (n = 9) and 27 ± 11 SD ml/100 g/min (n = 9), respectively.  相似文献   
48.
农村居民艾滋病防治知识及高危行为调查研究   总被引:6,自引:0,他引:6  
目的 通过对农村居民艾滋病 (AIDS)防治知识及高危行为的研究 ,为制定AIDS预防控制措施提供依据。方法 运用横断面调查研究方法 ,通过两阶段人群抽样对其AIDS防治知识及相关行为进行研究。结果 调查对象听说过AIDS的为 6 1.78% ;答对 0~ 3题为 5 6 .91% ,4~ 9题为 38.4 8% ,10~ 13题为 4 .5 5 % ;认为不可能感染艾滋病病毒的为 5 6 .94 % ,不清楚的为 38.38% ,有可能的为 4 .6 8%。 12人有卖血史 ,15人有性病史 ,在有性行为的 886人中 ,7.6 7%有过 1个以上多性伴。结论 农村居民AIDS知识匮乏 ,存在着相关危险行为。所以 ,我省预防AIDS的策略主要是开展健康教育积极推进健康促进 ,改善危险行为 ,提倡安全性行为和推广安全套的使用  相似文献   
49.
Summary The technique of antidromic mapping with a roving array of electrodes was used to demonstrate that lamina I trigeminothalamic cells responsive specifically to skin temperature project to the n. submedius (Sm) in the medial thalamus of the cat. This finding indicates that Sm receives thermoreceptive in addition to nociceptive information.  相似文献   
50.
The gonadotropin-releasing hormone-associated peptide (GAP) and luteinizing hormone-releasing hormone (LHRH) portions of the LHRH precursor were localized by immunocytochemistry in prepubertal female rats, in adult female rats at different stages of the estrous cycle, and in ovariectomized rats. Our results indicate that GAP is present in the same population of neurons as LHRH in the rat brain. These results confirm the specificity of previous immunocytochemical studies which used antisera to LHRH alone. The endocrine status of the animal was demonstrated to affect the immunocytochemical appearance of the GAP system. The number of GAP immunopositive cells and terminals is highest during diestrus II and lowest on the day of estrus, suggesting either a role in and/or a dependence upon the endocrine changes associated with the estrous cycle. Ovariectomy results in a gradual decrease in GAP immunoreactivity in the median eminence. This observation, in concert with other recent studies, suggests that ovarian factors may be acting to maintain the LHRH system and that ovariectomy may result in decreased synthesis and/or processing of the LHRH system and that ovariectomy may result in decreased synthesis and/or processing of the LHRH precursor.  相似文献   
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