关于Reed－Frost模型的研究和改进

笔者提出了对Ｒｅｅｄ－Ｆｒｏｓｔ模型的学术评论，并新建了一种Ｒｅｅｄ－Ｆｒｏｓｔ模型的改进模型。该改进模型全面考虑了隐性感染者的产生、传染作用及向免疫者的转化。应用这个模型，模拟了ＮｅｗＥｎｇｌａｎｄ的麻疹流行和中国上海市某保育院的水痘流行，结果颇为理想。该模型包括了基本的流行要因，故能用以解释流行过程，并可帮助流行病学工作者理解隐性感染在传染病流行过程中的作用。     

Serotonergic projections from the midbrain periaqueductal gray and nucleus raphe dorsalis to the nucleus parafasccicularis of the thalamus

By a double-labeling method combining the retrograde tracing of horseradish peroxidase and the immunocytochemical technique, serotonin-like immunoreactive neurons in the midbrain periaqueductal gray (PAG) and nucleus raphe dorsalis (DR) of the rat were observed to send projection fibers to the nucleus parafascicularis of the thalamus bilaterally with an ipsilateral dominance. These serotonin-containing projecting neurons were observed mainly at the middle-caudal levels of the ventrolateral subdivision of the PAG and less at the middle-rostral levels of the DR.     

Teriparatide increases bone formation in modeling and remodeling osteons and enhances IGF-II immunoreactivity in postmenopausal women with osteoporosis.

Transiliac bone biopsies were obtained from 55 women treated with teriparatide or placebo for 12-24 months. We report direct evidence that modeling bone formation at quiescent surfaces was present only in teriparatide-treated patients and bone formation at remodeling sites was higher with teriparatide than placebo. INTRODUCTION: Recombinant teriparatide [human PTH(1-34)], a bone formation agent for the treatment of osteoporosis when given once daily subcutaneously, increases biochemical markers of bone turnover and activation frequency in histomorphometry studies. MATERIALS AND METHODS: We studied the mechanisms underlying this bone-forming action of teriparatide at the basic multicellular unit by the appearance of cement lines, a method used to directly classify surfaces as modeling or remodeling osteons, and by the immunolocalization of IGF-I and IGF-II. Transiliac bone biopsies were obtained from 55 postmenopausal women treated with teriparatide 20 or 40 microg or placebo for 12-24 months (median, 19.8 months) in the Fracture Prevention Trial. RESULTS: A dose-dependent relationship was observed in modeling and mixed remodeling/modeling trabecular hemiosteons. Trabecular and endosteal hemiosteon mean wall thicknesses were significantly higher in both teriparatide groups than in placebo. There was a dose-dependent relationship in IGF-II immunoreactive staining at all bone envelopes studied. The greater local IGF-II presence after treatment with teriparatide may play a key role in stimulating bone formation. CONCLUSIONS: Direct evidence is presented that 12-24 months of teriparatide treatment induced modeling bone formation at quiescent surfaces and resulted in greater bone formation at remodeling sites, relative to placebo.     

浅谈多媒体教学中存在的问题及对策

分析了目前多媒体教学中存在的一些问题，提出了一些提高多媒体教学质量的途径和方法。     

去甲肾上腺素缩血管作用对犬冠状血管舒张的限制

在10只麻醉开胸犬的左前降支冠状动脉(LAD)恒流灌注,持续监测灌注压,并于冠脉内注入2.5mg心得宁以阻断心脏的β_1-肾上腺素能受体,观察去甲肾上腺素(NE,α-肾上腺素能刺激)对LAD内给予腺苷所致冠状血管舒张的限制作用。随着LAD内注入的腺苷量增加,冠状动脉阻力(R)咸剂量依赖性降低,分别为对照值的8.7％(2μg/min),20.6％(10μg/min)和28％(50μg/min)。而于LAD内再给予相同齐0量(6μg)的NE,则使不同剂量扩张的冠脉收缩,R成阶梯状增加,分别为对照值的17.4％(腺苷2μg/ml),23.2％(腺苷10μg/min)和34.1％(腺苷50μg/min),表现为隙苷引起的冠状血管扩张愈大,NE能刺激引起的缩血管作用愈强。这表明α-肾上腺素能缩血管作用可限制腺苷引起的冠状血管舒张,因而有助于保持冠状血管张力及其储备力。     

高压氧治疗尺桡神经损伤疗效观察

应用高压氧治疗尺桡神经损伤修复术后１１例，与同期单纯手术修复１４例相比，优良率明显提高，二组间有显著差异。Ｐ＜０．０５，提示高压氧对尺桡神经损伤的修复有促进作用     

大鼠马桑内酯急性局灶型癫痫大脑运动皮质的形态计量研究

用微量马桑内酯注入Ｗｉｓｔａｒ大鼠左侧前肢运动皮质，造成急性局灶型癫痫。用光镜、电镜和体视学方法研究其运动皮质第Ｖ层结构的改变。结果显示：癫痫大鼠运动皮质灶区、灶旁区的神经细胞数和胶质细胞数均分别比对照大鼠灶区和灶旁区显著减少；灶区神经毡中突触性终末数，显著减少；突触性终末的面积分数明显减少，而树突的面积分数无变化；神经胶质突起的面积分数增加。     

先天性心脏病患儿肺动脉,上腔静脉血一氧化氮含量检测及意义

目的:探讨一氧化氮(NO)与先天性心脏病(CHD)引起的肺动脉高压(PH)发病间的关系。方法:应用NO试剂盒检测了CHD患儿肺动脉及上腔静脉血浆中NO含量。结果;(1)伴PH组肺动脉血浆NO含量明显高于不伴肺动脉高压组(37.58±9.99μmol/L:19.03±15.25μmol/L,P<0.01);(2)在PH组中,肺动脉血浆NO含量明显高于上腔静脉血(P<0.01);而不伴PH组,肺动脉和上腔静脉血浆NO含量无显著性差异(P>0.05)。结论:(1)伴PH的先心患儿肺动脉血浆NO含量升高;(2)NO可能介入了CHD引起的PH发病过程。     

腹部CTA检查的质量保证

目的:探讨螺旋CT血管造影(Spiral CT angiography,SCTA)技术,以期提高SCTA造影的质量。材料与方法:采用Somatom Plus 4螺旋CT扫描系统对10例病人行腹部SCTA检查。扫描技术和造影剂参数按病变范围和性质而定,三维重建采用最大强度投影法(MIP)或表面阴影显示法(SSD)或弯曲平面重建法(CPR)。结果:SCTA检查技术能可靠地显示血管形态和病变,评价腹部肿瘤与邻近血管关系。结论:SCTA是无创伤性的血管成像术,在很大范围可替代创伤性的血管造影。