混合Poisson分布及其应用：疾病的统计分布（五）

本文讨论了混合Ｐｏｉｓｓｏｎ分布的性质、应用条件、参数的估计及混合Ｐｏｉｓｓｏｎ分布阶数的确定，指出混合Ｐｏｉｓｓｏｎ分布可用于混合样本的判别归类，并用Ｂａｙｅｓ的思想导出其判别归类方法。模拟试验结果表明：当混合Ｐｏｉｓｓｏｎ分布中各部分的比例相差不大，而各部分的均值相差较大时，抽样效果和拟合效果越好，所得到的估计值越接近理论值；反之效果越差。     

广东省城乡街头食品存在问题分析

1994年随机抽取广东省20个市315家街头食品经营户，按《广东省街头食品卫生检查评分标准》进行审评，结果，一类户占8．6％，二类户占43．8％，三类占47．6％．存在主要问题是饮食经营场所不卫生和设施简陋．食具消毒卫生质员不能有效得到保证．食品交叉污染因素较多，存在引发食物中毒潜在危险．食品从业人员个人卫生意识差．食品卫生监督力量薄弱，管不胜管．     

Plasmid DNA encoding transforming growth factor-beta1 suppresses chronic disease in a streptococcal cell wall-induced arthritis model.

Transforming growth factor beta is a potent immunomodulator with both pro- and antiinflammatory activities. Based on its immunosuppressive actions, exogenous TGF-beta has been shown to inhibit autoimmune and chronic inflammatory diseases. To further explore the potential therapeutic role of TGF-beta, we administered a plasmid DNA encoding human TGF-beta1 intramuscularly to rats with streptococcal cell wall-induced arthritis. A single dose of 300 microg plasmid DNA encoding TGF-beta1, but not vector DNA, administered at the peak of the acute phase profoundly suppressed the subsequent evolution of chronic erosive disease typified by disabling joint swelling and deformity (articular index = 8.17+/-0. 17 vs. 1.25+/-0.76, n = 6, day 26, P < 0.01). Moreover, delivery of the TGF-beta1 DNA even as the chronic phase commenced virtually eliminated subsequent inflammation and arthritis. Both radiologic and histopathologic as well as molecular evidence supported the marked inhibitory effect of TGF-beta1 DNA on synovial pathology, with decreases in the inflammatory cell infiltration, pannus formation, cartilage and bone destruction, and the expression of proinflammatory cytokines that characterize this model. Increases in TGF-beta1 protein were detected in the circulation of TGF-beta1 DNA-treated animals, consistent with the observed therapeutic effects being TGF-beta1 dependent. These observations provide the first evidence that gene transfer of plasmid DNA encoding TGF-beta1 provides a mechanism to deliver this potent cytokine that effectively suppresses ongoing inflammatory pathology in arthritis.     

缺氧缺血性脑病新生鼠补钙前后脑细胞,红细胞内外钙的变化

为了观察一般剂量补钙对缺氧缺血性脑病（ＨＩＥ）脑细胞和红细胞内外钙变化的影响，以探讨ＨＩＥ时补钙是否增加脑细胞钙超载，用ＨＩＥ新生动物模型进行了实验研究，结果表明：（１）缺氧缺血时红细胞、脑细胞及脑组织出现钙积聚；（２）补钙后，血浆总钙浓度明显升高，而脑细胞、脑组织及红细胞钙积聚并未加重；（３）血浆总钙浓度与脑细胞或红细胞胞浆游离钙离子浓度无相关关系。提示：（１）ＨＩＥ时钙内流可能是全身性的；（２）对ＨＩＥ并低钙血症患儿吸氧后一般剂量补钙可能是安全的。     

大脑后动脉交通前段及其内穿支研究

本文介绍Willis动脉环后半环大脑后动脉及其内穿支的显微解剖,大脑后动脉交通前段内穿支是脑深部的重要供血血管之一,100％的病例双侧具有该血管。     

白血病细胞p16基因突变分析

目的探讨ｐ１６基因突变在白血病发生中的作用及基因突变的机制。方法利用点突变检测仪、水平和垂直板电泳对ｐ１６基因的外显子１、外显子２的ＰＣＲ扩增产物作缺失和点突变分析。结果在白血病３５例临床标本中有２２例发生缺失突变，６例发生点突变，突变率约８０％。在２２例缺失突变病例中，有１０例为不完全缺失突变即有低于外显子５０９ｂｐ的扩增产物。结论ｐ１６基因含有“ＧＣ”ＤＮＡ重复顺序，易发生ＤＮＡ重组及易位和重排。在白血病发生中起重要作用     

石家庄地区汉族人群DIS80(pMCT118)位点VNTR基因频率分布调查

本文采用ＰＣＲ技术对石家庄地区２１６名无关个体ＤＩＳ８０（ｐＭＣＴ１１８）位点扩增片段长度多态性的等位基因频率进行调查。ＰＣＲ扩增产物采用聚丙烯酰胺凝胶电泳分型及溴化乙锭染色，共检出７０种基因型，２５个等位基因，其中以１８、２４、３０三个等位基因频率最高。将本文结果与日本人群在ＤＩＳ８０（ｐＭＣＴ１１８）位点多态性结果进行比较，石家庄地区汉族人群ＤＩＳ８０（ｐＭＣＴ１１８）位点基因频率分布符合ＨａｒｄｙＷｅｉｎｂｅｒｇ平衡定律，该位点非父排除率为０．７１，个体识别率为０．９，杂合度为０．８５。     

外科手术患者1 820例术前几种传染病感染情况

目的了解内蒙古自治区医院各类需要外科手术治疗患者的乙型肝炎病毒（HBV）、艾滋病病毒（HIV）和梅毒的感染情况，以便合理地采取相应的措施，减少交叉感染的发生。方法采用ELISA法检测需手术患者血清中HBV抗原和抗体及HIV、苍白密螺旋体（TP）抗体。结果被检对象HBV感染阳性率为4．51％，TP阳性率为1．42％。结论应加强外科手术患者的术前传染病血清学检测，针对性地采取相应措施，以减少经手术传播的概率。     

Morphological and biochemical studies of a mouse mutant (fro/fro) with bone fragility.

The mutation fragilitas ossium (fro) was discovered in a random-bred stock of mice during an experiment aimed at detecting recessive lethal mutations after treatment of the postmeiotic germ cells of male mice with tris (1-aziridinyl)phosphine sulphide. The affected mice were moderately runted and had deformities in all four limbs. The radiological and histological findings indicate that the mutant is similar to human osteogenesis imperfecta. The ash content of long bones was lower in the mutant. A defect of type I collagen could not be detected. The electrophoretic patterns of alpha bands of type I and V collagen and CB derived peptides of type I collagen from bone and skin showed no abnormalities. The total collagen synthesis and secretion in cultures of dermal fibroblasts, as well as the gel electrophoresis of procollagen and collagen chains synthesized, and of their CB peptides, were the same as those found in the controls. The percentage of type I and type V collagen synthesized was similar; that of type III was lower in the mutants. Bone osteonectin was found to be decreased by 30% and bone sialoprotein by 5%. The mRNA level for osteonectin was decreased in the fibroblasts of the mutant by about 50%. Whether the defective expression of the osteonectin in fro/fro mice is due to a mutation in the gene itself or its regulatory site(s), or is secondary to other factors remains to be established. The fro/fro mouse may represent a model for some forms of human bone fragility without collagen abnormalities.