骨碎补化学成分和生物活性研究进展＊

骨碎补是历代临床常用中药，具有疗伤止痛、补肾强骨、消风祛斑等功效。其主要含黄酮、苯丙素、三萜、酚酸及其苷等类化学成分，现代研究表明骨碎补具有抗骨质疏松、促进骨折愈合、促软骨再生、护牙健齿、保护肾功能、抗炎、防治中毒性耳聋、降血脂等多种生物活性，开发前景广阔。本文对近年来骨碎补的化学成分、药理作用及临床应用研究进行综述，以期为骨碎补的进一步深入系统的研究和开发利用提供依据。     

反义人端粒酶RNA组分基因对胃癌细胞端粒酶活性的影响

目的 克隆人胃癌细胞端粒酶RNA组分（hTR）基因片段并构建其正义和反义真核表达载体,研究反义端粒酶RNA对人胃癌细胞株MKN-45端粒酶活性的影响。方法 采用RT-PCH方法从人胃癌细胞株MKN-45中扩增出人hTR部分cDNA序列,将该片段分别正向和反向插入PEF6/V5-His-TOPO载体后构建人端粒酶RNA组分（hTR）基因正、反义真核表达载体,随后采用脂质体转染法将该正、反义载体转染入人胃癌细胞株MKN-45,用TRAP法观察后者端粒酶活性的改变。结果 所克隆的基因片段其碱基序列与文献报导完全一致,且插入载体的方向完全正确。与正常对照、转染正义载体、空载体者比较,转染反义载体者端粒酶活性显著下降。结论 本实验已成功克隆了人端粒酶RNA组分（hTR）基因的部分序列并成功构建hTR正反义真核表达载体,而且反义端粒酶RNA能有效降低人胃癌细胞株MKN-45端粒酶活性。     

薄壁构件的高温低周疲劳寿命的预测与验证

提出了文题的计算模型,它采用非线性弹塑性蠕变有限元法,计算构件危险点在高温及周期保载的交变载荷谱作用下的应力应变响应,以应变范围区分法累积损伤,从而求出构件的疲劳寿命,并以带孔矩形薄板为例作了计算与验证,结果吻合较好,可供工程应用。     

五虎汤制剂及其有效部位群的药效学比较

目的:对五虎汤制剂及其有效部位群的镇咳、平喘、化痰作用进行药效学比较。方法:采用二氧化硫引咳、枸橼酸引咳、组胺—乙酰胆碱引喘和气管酚红排泄实验进行研究。结果:二者能显著延长二氧化硫及枸橼酸引咳的潜伏期;能显著延长组胺-乙酰胆碱混合液喷雾所致豚鼠喘息发作的潜伏期。结论:有效部位群各剂量组的疗效与同剂量制剂组在止咳、平喘、化痰作用上基本相当。     

Inverting a Laplacian topography map

Summary There are some occasions when it is better to use the Laplacian of the scalp voltages (e.g., for topographic displays and dipole source localization) and other occasions when it is better to use the original voltages (e.g., for comparison to non-Laplacian topography maps). This paper presents a simple algorithm for going between these two representations of the data. The inverse Laplacian involves iterative feedback. An Excel spreadsheet implementation of the algorithm is presented.This research was supported by grant AFOSR 89-0238 from the Air Force Office of Sponsored Research.     

A genetic and environmental time series analysis of blood pressure in male twins

Systolic and diastolic blood pressures were measured on 254 monozygotic (MZ) and 260 dizygotic (DZ) male twin pairs, during middle age (average age 48 years) and at two later age points. Genetic and environmental components of covariation were modeled by time series. For both measures, shared environmental influences were absent and specific environmental influences were largely time-specific. Although heritability was about 0.5 at each time point, genetic variation present at middle age contributed only about 60% to that present 9 years later, the remaining 40% being new. Fifteen years later, at the third time point, no new genetic variation was evident, variation in individual differences being entirely attributable to genetic differences laid down at the two earlier ages. © 1993 Wiley-Liss, Inc.     

Effect of dietary fat content on the bioavailability of a sustained release quinidine gluconate tablet

Quinidine gluconate 324 mg sustained release tablets (Quinaglute) was administered as a single dose to 15 healthy male subjects following an overnight fast, immediately following a high fat (HF) breakfast or immediately following a low fat (LF) breakfast. Serum samples were obtained over a 48 h period and analyzed for quinidine content using a high performance liquid chromatographic assay. Under the conditions of the study, both the rate and extent of quinidine bioavailability was significantly affected by food. The extent of bioavailability was statistically significantly greater (p less than 0.05) following both the HF and LF meals as compared to that in the fasted state. Rate of bioavailability was significantly enhanced following the LF meal as compared to that of the other two treatment groups. Although peak concentrations were greater and time to peak concentrations somewhat later following the HF meal versus those under fasting conditions, these differences were not statistically significant. In addition, the characteristics of the serum concentration-time profile (as defined by the number, magnitude, and time of occurrence of the multiple absorption maxima) was unique for each of the three treatment groups. Possible mechanisms underlying these results are explored.     

Soluble Fcγ receptors in periodontal lesions

Soluble Fcγ-binding components were detected in gingival fluid from periodontal lesions by incubation with biotinylated human Fcγ fragments. FcγIII receptor was identified by incubation of gingival fluid with monoclonal antibody. Sodium dodecyl sulfate-polyacrylamide gel electophoresis and Western transfer showed that most of the Fcγ-binding components had minimal mobility in a 4–15% gradient gel under nonreducing conditions. Under reducing conditions, the main band of Fcγ-binding components in gingival fluid migrated corresponding to protein A of 49 kDa. The pattern of Fcγ-binding components was similar in serum and gingival fluid except for the observation in gingival fluid of Fcγ-binding components migrating like standard proteins of 19 to 20 kDa, a size that corresponds to the polypeptide part of FcγII receptor and FcγIII receptor.     

几种抗艾滋病中药有效成分对解脲支原体和白色念珠菌体外抑制作用的实验研究

目的筛选对解脲支原体和白色念珠菌体外有明显抑制作用的抗H IV中药有效成分,为治疗H IV继发感染或性病奠定基础。方法以微量稀释法测定9种中药有效成分对解脲支原体和白色念珠菌的M IC50和M IC90,同时测定其中6种中药有效成分对H IV-1的EC50和TI值。结果所测药物对解脲支原体、白色念珠菌及H IV-1均有一定的抑制作用,对解脲支原体和白色念珠菌作用最好的分别是三七总皂苷、三七叶皂苷和化合物A,化合物A对H IV-1的抑制作用最好,其EC50为0.09,TI值大于10 000。结论化合物A对解脲支原体、白色念珠菌及H IV-1的抑制效果最好,值得进一步研究。     

中药止血成分的研究进展

中药止血药应用历史悠久,且资源分布广泛,常见的就有300余种,在其研究中发现了大量的止血活性成分.已知的中药止血成分几乎囊括了各类化学成分,包括氨基酸、生物碱类、萜类和甾体、酚类和黄酮类、鞣质、醌类、苯丙素类、脂类、有机酸类等.按植物化学分类学对已报道的一些中药止血成分进行分类综述,为研究发现新的止血成分和开发止血新药提供一些借鉴.