Neural networks in the study of the brain

Neural networks are models of the brain and have been used within Artificial Intelligence to provide alternative explanations to the symbolic explanations of cognition in which one assumes that an intelligent system has certain explicit representations of some aspect of the world and uses these in intelligent behavior. Obviously, if neural networks are indeed good models of the brain, and give a satisfactory account of cognition, then they could be a valuable tool to neuroscientists. This article gives a brief overview of the various neural network models, and critically reviews their status as models of the brain and of cognition.     

小脑萎缩的临床CT诊断

报告手术证实小脑萎缩110例,主要CT表现为小脑半球及(或)蚓部脑沟增多,增宽及不同程度第四脑室、桥前池、桥小脑角池、环池及小脑上池扩大。建议采用后颅窝薄层扫描以减少或避免后颅窝伪影干扰。提出小脑半球或蚓部脑沟在2条以上,小脑半球脑沟宽度超过1mm,蚓部脑沟宽度超过2mm,并有相应的小脑症状及体征,即可诊为小脑萎缩。还讨论了小脑萎缩的原因及其CT表现。     

双抗体夹心法检测胆管癌患者血清中胆管癌相关抗原的临床意义

胆管癌相关抗原（ＣＣＲＡ）是我们从人胆管癌组织中提取的一种新的肿瘤标志物。建立了检测ＣＣＲＡ的ＥＬＩＳＡ方法，检测了４０例正常人及２６８例良恶性疾病病人血清的ＣＣＲＡ浓度，后者包括胆管癌３６例、原发性肝癌４０例、胰腺癌２６例、胃癌３１例、结直肠癌３４例、肺癌１７例、肝硬变２０例、胆石症４０例及胃溃疡２４例。结果显示：４０例正常对照组的血清ＣＣＲＡ浓度为（１４．３８±７．３４）μｇ／ｍｌ（ｘ±ｓ），正常上限为２８．９５μｇ／ｍｌ（ｘ＋２ｓ）；血清ＣＣＲＡ诊断胆管癌的敏感性是７７．７８％，明显高于其它肿瘤组（０～２５）％（Ｐ＜０．００１），特异性是（７５～１００）％。认为对于胆管癌的诊断，ＣＣＲＡ可能是一种较特异的肿瘤相关抗原。     

IgA肾病和非IgA系膜增殖性肾小球肾炎抗内皮细胞抗体的检测

对１２７例ＩｇＡ肾病（ＩｇＡＮ）患者和２５例非ＩｇＡ系膜增殖性肾炎血清进行了抗内皮细胞抗体ＡＥＣＡ的检测。结果表明：ＩｇＡ肾病患者和非ＩｇＡ系膜增殖性肾炎患者血清ＡＥＣＡ－ＩｇＧ较正常对照组高，而ＩｇＡＮ患者较非ＩｇＡ系膜增殖性肾炎患者ＡＥＣＡ－ＩｇＧ的水平高，Ｐ〈０．０５。ＩｇＡＮ患者的ＡＥＣＡ－ＩｇＡ水平较正常对照组高。ＩｇＡＮ患者按ＡＥＣＡ水平分为阳性与阴性组，对两组硬化面积比进行比较，未见     

几种植物来源不同作用机制的抗癌药抗侵袭作用

用细胞培养法和癌细胞侵袭实验,观察几种植物来源不同作用机理的抗癌药如紫杉醇、三尖杉酯碱、高三尖杉酯碱及喜树碱^[1],对黑色素瘤高转移株B16-BL6细胞及人纤维肉瘤细胞HT-1080的细胞毒作用和抗侵袭作用。结果表明紫杉醇、三尖杉酯碱、高三尖杉酯碱及喜树碱对B16-BL6和HT-1080细胞增殖均有很强的抑制作用。紫杉醇、三尖杉酯碱及高三尖杉酯碱对B16-BL6细胞侵袭和运动也有明显的抑制作用,而喜树碱在同样浓度下对B16-BL6细胞侵袭和运动均无明显抑制。     

病房康复延伸护理对脑卒中迟缓性偏瘫患者三维步态时空参数的影响

目的:观察病房康复延伸护理对脑卒中迟缓性偏瘫患者三维步态时空参数的影响。方法:将60例脑卒中迟缓性偏瘫患者随机分为常规护理组(A组,n=30)、病房康复延伸护理组(B组,n=30)两组,予以相应的方法治疗8周,评估治疗前后两组患者三维步态时空参数。结果:与治疗前相比,治疗后两组患者的步长、步幅、步速、步频、支撑相、双支撑相等参数及B组摆动相均有不同程度的改善(P<0.05); A组摆动相和步宽及B组步宽的变化差异无统计学意义(P>0.05)。与治疗后A组比较,治疗后B组的步长、步幅、步速、步频、支撑相、双支撑相等参数改善较为明显(P<0.05),步宽和摆动相的改善差异无统计学意义(P>0.05)。结论:病房康复延伸护理能改善脑卒中迟缓性偏瘫患者三维步态时空参数,具有临床意义。     

A variety of microorganism species at the burn ward

From 1975 to 1987, 965 exudate cultures of burn wounds were done in 553 cases. 1205 colonies (28 species) of microorganisms were separated out from these patients. Among 1205 colonies, 1050 colonies (87.13%) were "common microorganism" included P. aeruginosa, E. coli, S. aureus, and P. vulgaris. There were mixed infection of P. aeruginosa and E. coli in 23.66-25.95% cases. In early stage P. aeruginosa (23.25%) was predominant and in late stage, S. aureus was predominant. The sensitivity of microorganisms to 18 kinds of antibiotics gradually decreased, year by year. The authors consider that reasonable use of antibiotics, early eschar excision and skin grafting play an important role in decreasing the occurrence of drug-fast bacteria and preventing cross infection.     

Cytocidal action of homoharringtonine on L1210 cells in vitro

The proliferation of L 1210 cells ceased rapidly after they were exposed to homoharringtonine (HH) 1 microgram/ml during exponential growth phase. However, 25.3% of the cells were still able to form colonies in soft agar if HH was removed after 24 h of incubation (the colony-forming efficiency for control cells was 62.5%). The clonogenic cells survived from the treatment were still sensitive to HH-continuous exposure. The IC50 of the treated and control cells were 15 and 20 ng/ml, respectively. Yet, the sensitivity of the treated cells to cytarabine decreased enormously. For instance, the survival rate of HH-treated cells remained at 100% level after they were exposed to cytarabine 4-8 micrograms/ml for 1 h, but only 40% control cells survived from the same treatment. When cells were continuously exposed to HH 0.4 micrograms/ml, the colony-forming efficiency decreased exponentially as a function of exposure time. The T1/2 of the clonogenic cells was about 18 h. The DNA contents in L 1210 cells was measured with a flow-cytometer. The results showed that the cell-cycle progress in all cells was interrupted by HH, regardless which phase they belonged to. So the cells seemed to be in a "frozen" state and the histogram unchanged.