Receptor-activated Ca2+ influx via human Trp3 stably expressed in human embryonic kidney (HEK)293 cells. Evidence for a non-capacitative Ca2+ entry

Gonadal differentiation involves a complex interplay of developmental pathways. The sex determining region Y (SRY) gene plays a key role in testis determination, but its interaction with other genes is less well understood. Abnormalities of gonadal differentiation result in a range of clinical problems. 46,XY complete gonadal dysgenesis is defined by an absence of testis determination. Subjects have female external genitalia and come to clinical attention because of delayed puberty. Individuals with 46,XY partial gonadal dysgenesis usually present in the newborn period for the valuation of ambiguous genitalia. Gonadal histology always shows an abnormality of seminiferous tubule formation. A diagnosis of 46,XY true hermaphroditism is made if the gonads contain well-formed testicular and ovarian elements. Despite the pivotal role of the SRY gene in testis development, mutations of SRY are unusual in subjects with a 46,XY karyotype and abnormal gonadal development. 46,XX maleness is defined by testis determination in an individual with a 46,XX karyotype. Most affected individuals have a phenotype similar to that of Klinefelter syndrome. In contrast, subjects with 46,XX true hermaphroditism usually present with ambiguous genitalia. The majority of subjects with 46,XX maleness have Y sequences including SRY in genomic DNA. However, only rare subjects with 46,XX true hermaphroditism have translocated sequences encoding SRY. Mosaicism and chimaerism involving the Y chromosome can also be associated with abnormal gonadal development. However, the vast majority of subjects with 45,X/46,XY mosaicism have normal testes and normal male external genitalia.     

High Temperature Solid Oxide Fuel Cells(SOFC)

The history and the state of the art of solid oxide fuel cells(SOFC)is reviewed in this paper.Itdescribes mainly on the material selection,structure design and technological economics of SOFC.The appli-cation of great amount of rare earth materials in SOFC may well extend the market potential of rare earthmaterials in the world.A research project to be carried out as early as possible in China on the SOFC tech-nology will be far-reaching.     

用MONTECARLO方法研究分光光度法在比色分析中的精度

对使用分光光度法进行比色分析时的误差特性及工作曲线的计算做了讨论，给出了在测试数据不等时的拟合工作曲线的最小二乘算法，并使用ＭｏｎｔｅＣａｒｌｏ方法定量地分析了测试精度与试验条件间的具体关系。     

Mitogenic effect of erythropoietin on cultured aortic myocytes

The administration of recombinant erythropoietin (rHuEpo) to anemic chronic renal failure patients may be associated with an increase in blood pressure, possibly by direct effects on peripheral blood vessels. In the present study, experiments were designed to explore the hypothesis that rHuEpo could enhance vascular resistance through mitogenic effect on vascular smooth muscle cells (VSMCs), and that preexisting hypertension might be a predisposing condition. Cultured VSMCs from the thoracic aortae of spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats were studied for DNA synthesis, phospholipase C activity, and cell growth related proto-oncogene expression in the presence of rHuEpo. In cells from both strains, rHuEpo dose-dependently increased DNA synthesis and stimulated phospholipase C activity, as indicated by 3H-thymidine incorporation and 3H-inositol phosphate formation, respectively (EC50 approximately 4 U/ml). Exposure of VSMCs to rHuEpo for various times gradually increased the levels of c-myc and junB and transiently induced c-fos expression, as determined by Northern analysis. rHuEpo-induced DNA synthesis was markedly enhanced in VSMCs from SHR compared to those from WKY. In contrast, rHuEpo-induced phospholipase C activity and proto-oncogene expression did not differ between the two strains. Taken together, these results suggest that rHuEpo may function as a vascular smooth muscle cell growth promoting factor through activation of the phospholipase C cascade and modulation of proto-oncogene expression. It could thereby contribute to vascular hypertrophy and arterial hypertension.     

新型合金代铬刷镀层的组织及强化机理的研究

采用Ｘ射线衍射仪，透射电镜和扫描隧道显微镜等手段对新型代铬镀层（Ｎｉ－Ｆｅ－Ｗ－Ｐ－Ｓ）相结构及组织进行了研究，并初步探讨了镀层的强化机理。研究表明，Ｎｉ－Ｆｅ－Ｗ－Ｐ－Ｓ合金镀层的组织是由含Ｆｅ、Ｗ、Ｐ、Ｓ的镍基固溶体和在其上弥散分布的金属间化合物Ｎｉ_３Ｆｅ所组成，镍基固溶体处于非晶和微晶的混合状态，合金镀层的镀态硬度为ＨＶ７００～７５０，在３００℃退火时。硬度达到最大值ＨＶ９００～９５０，其强化机理主要是微晶的晶界强化和Ｎｉ_３Ｆｅ的弥散强化。     

奇、偶相干热态中的光场统计性质

本文讨论了热混饨光场态参与时对奇、偶相干态的光场统计性质影响。结果表明，热光场态的存在使偶相干态的压缩效应和奇相干态中的反聚束效应减弱。     

溅渣护炉技术在转炉上的应用

从１９９６年开始实施溅渣护炉试验研究，一年来的工业性试验与实验室研究表明：所用的溅渣护炉工艺参数基本可行，溅渣护炉条件下复吹比达５０％，炉衬砖消耗下降０．７ｋｇ／ｔ，喷补料消耗下降１．２２ｋｇ／ｔ。试验证明开发新型调渣剂是进一步提高溅渣护炉效果的重要措施。     

动载荷下应力强度因子的边界元计算

用Ｎａｒｄｉｎｉ－Ｂｒｅｂｂｉａ边界元法计算了动载荷下的应力强度因子，与解析解及有限元解相比较，效果较好。最后对计算结果进行了分析讨论。     

碳/环氧复合材料的冲击拉伸

该文研究了T300碳纤维单向增强的环氧复合材料,在应变率从10~(-3)/s到10~3/s范围内的冲击拉伸行为.通过对实验数据进行拟合,得出该范围内材料对应变率具有弱的敏感性,表现在破坏强度及破坏应变随应变率增加不显著变化,平均模量几乎不受应变率的影响.分析了试件的几何尺寸效应,讨论了应力波作用对破坏形态的影响以及实验中观察到的拔出现象.从应变率在10~2～10~3/s附近材料行为某些非确定性,指出在更宽范围内了解其性能的必要性.     

基于自组织神经网络的实时统计特征抽取方法

应用人工神经网络讨论统计了特征抽取的原理，提出了相应的抽取方法。该方法具有实时性，容错性，高数据压缩率和良好的特征分辨率。通过计算机仿真和桥梁索力状态的实例计算分析证实了该技术具有广泛的应用价值。