In vivo structure–activity studies on the dark‐color‐inducing neurohormone of locusts

In the 11‐residue long dark‐color‐inducing neurohormone (DCIN = [His⁷]‐corazonin), of locusts, from residue 2 to residue 11, one amino acid at each time was substituted by d ‐phenylalanine (d ‐Phe). The dark‐color‐inducing effect of these peptides was investigated in comparison with unaltered DCIN by a bioassay based on nymphs of a DCIN‐deficient albino mutant of the migratory locust, Locusta migratoria. Substitution of any single amino acid by d ‐Phe always reduced the activity, but did not abolish it completely. Maximum inactivation was obtained after substitution of Gln4, Ser6, or Trp9. The latter two residues are within the partial sequence ‐Ser‐Xxx‐Gly‐Trp‐ (Xxx = His in the DCIN) that seems to be important for the dark‐color‐inducing activity, as found also in another study (Insect Biochem. Mol. Biol. 32, 2002, 909). Gln4, however, is outside of this partial sequence. Minimal, although still considerable, inactivation occurred after substitution of Gly8, Phe3, or Asn11, despite the fact that Gly8 is within the ‐Ser‐Xxx‐Gly‐Trp‐ partial sequence. In conclusion, no single active core was found, indicating that the whole sequence of the DCIN is necessary to induce maximum darkening effect. No difference was found in the activity of the peptides in which Gly8 was substituted by d ‐Phe or by L ‐Phe. Therefore the ‐Ser‐Xxx‐Gly‐Trp‐ partial sequence does not seem to be stabilized by a type II β‐turn. Nevertheless, existence of another kind of turn that includes this partial sequence is feasible. A single unsuccessful attempt was made to discover an antagonist to the DCIN.     

论单核苷酸多态性与中医证的个体差异

单核苷酸(nucleotide)是基因的基本组成单位，单核苷酸多态性(Single Nacl eotide Poly morPhism,SNP)是指任何两个不同个体之间的单核苷酸序列中均有不同的排列次序，导致遗传变异而形成不同个体的差异性和多样性。它是决定人的个体差异的主要因素，是遗传的变异性所引起。个体差异是个体机体功能相对偏差以保持动态稳定的特征，是潜在的病理因素，其发病具有质化特点。证以质为基础，质以证的形式表现出来，证的特征包含着质的特征，证往往随质而转移，证的个体差异与单核苷酸多态性有关，这是中西医结合研究的最佳切入点。建立证与药的单核苷酸组学，可阐明中医药防治疾病原理，实现个体化医学治疗的理想，体现中医治病求本和防治未病的思想。     

钛基底对钛-瓷修复体表面色的影响

目的　探讨钛金属基底对钛 -瓷修复体表面色是否有明显影响。方法　制作 Dentsply DETREY- Carat瓷粉与钛 -瓷修复体标准试件 ,用 CS- 5型分光光度计测色 ,统计分析测定结果 ,并计算色差。结果　钛金属基底与Ni- Cr金属基底间颜色差异较大 ,但加不透明瓷及牙体瓷后 ,两组试件各色度指标统计学上无显著性差异 ,色差均小于 1.5。结论　钛金属基底对钛 -瓷修复体表面色无明显影响 ,Dentsply两种瓷粉同色瓷间无明显颜色差异。     

用薄层层析法检测鞣质

硅胶薄层层析法检测中药制剂的鞣质,斑点集中清晰,重现性好,灵敏度高。亚硝酸钠试剂显色,未见报道,对鞣质的分解产物没食子酸独显亮黄绿色,专属性强。用以检测没食子酸可供衡量制剂质量参考。     

彩色多普勒组织显像在小儿病毒性心肌炎诊断中的应用

本文报告用彩色多普勒组织显像(DTI)测定正常小儿173名,病毒性心肌炎40例,发现DTI在正常小儿的规律。病毒性心肌炎二尖瓣环舒张早期运动速度(MVR-DeV)显著低于正常儿童,40例病毒性心肌炎MVR-DeV降低者占72.5％,经过治疗后MVR-DeV90％以上短期内恢复正常。MVR-DeV降低率显著高于心脏解剖、心功能、心脏血流参数、心电图和心肌酶的异常率。因此,MVR-DeV对病毒性心肌炎的诊断、病情了解以及疗效观察均有重要价值。     

婴幼儿先天性心脏病合并室缺的肺动脉压测定研究

目的探讨婴幼儿先天性心脏病合并室缺的肺动脉压测定与连续波多普勒法相关性的临床研究。方法40例婴幼儿先天性心脏病合并室缺患者分为两组，以室缺合并平均肺动脉压〉20mmHg为观察组，室缺合并平均肺动脉压〈20nm、Hg为对照组，应用连续波多普勒法与术前用导管法所测肺动脉压进行比较。结果观察组连续波多普勒法测出肺动脉压与导管所测肺动脉压显著相关（r=0．70，P〈0．01），可达到定量诊断肺动脉高压的目的；对照组不紧密相关（r=0．65，P〉0．05）。结论连续波多普勒法对婴幼儿先天性心脏病合并室缺的患儿的肺动脉压评估可靠。     

Kappa opioid receptors in rat spinal cord vary across the estrous cycle

Kappa opioid receptors (KORs) were immunocytochemically localized in the lumbosacral spinal cord of female rats in different stages of the estrous cycle to examine the influence of hormonal status on receptor density. KOR labeling was primarily in fine processes and a few neuronal cell bodies in the superficial dorsal horn and the dorsolateral funiculus. Quantitative light microscopic densitometry of the superficial dorsal horn revealed that rats in diestrus had significantly lower KOR densities than those in proestrus or estrus. This suggests that female reproductive hormones regulate spinal KOR levels, which may contribute to variations in analgesic effectiveness of KOR agonists across the estrous cycle.     

应用彩色血流像素定量技术分析子宫肌瘤介入治疗后的血流灌注变化

目的提出一种新的基于计算机彩色目标分割技术的声像图彩色血流像素定量技术。方法应用笔者开发的计算机彩色血流像素定量软件 ,分析经阴道超声引导下穿刺注射无水酒精治疗子宫肌瘤前后的血流灌注状态变化 ,对照组应用半定量计数法分析血管条数增减评介血流灌注变化。结果应用计算机彩色血流像素定量软件统计肿块血流像素/肿块像素的比值 ,介入前肿块血流像素/肿块像素比值是(15.65±9.61) % ,介入治疗后第4～6个月减少为(5.91±3.35) % ,半定量血管计数结果分别为(4.8±2.34)条和(1.23±0.59)条 ,后者结果的准确性低于应用计算机彩色血流像素定量技术自动检测的结果。结论通过临床应用分析 ,使用计算机彩色血流像素定量技术 ,对兴趣区血流灌注状态进行定量分析的方法 ,比传统半定量方法的定量概念、精确度和可操作性都有了进一步的改进和提高。     

彩色多普勒超声对门静脉高压食道胃底静脉曲张破裂出血的判断

目的　探讨应用彩色多普勒超声对门静脉高压食道胃底静脉曲张破裂出血的判断价值。方法　根据门静脉高压食道胃底静脉曲张患者有无出血分为出血组 (2 5例 )、未出血组 (2 5例 )与健康对照组 (15例 )进行对比分析。结果　出血组、未出血组与健康对照组门脉充血分数分别为 :0 .12 6± 0 .0 5 6、0 .0 6 0± 0 .0 2 0、0 .0 34± 0 .0 15 ,出血组与未出血组比较有显著差异 (P <0 .0 0 1) ;胃左静脉内径分别为 :(0 .89± 0 .2 6 )cm、(0 .70± 0 .2 4 )cm、(0 .31± 0 .0 7)cm ,出血组与未出血组比较有显著差异 (P <0 .0 5 ) ;出血组与未出血组食道曲张静脉内径分别为 :(0 .4 9± 0 .12 )cm、(0 .34± 0 .11)cm ,两者比较有显著差异 (P <0 .0 1) ;食道曲张静脉内血流速度分别为 (17.9± 7.4 )cm s、(11.1± 6 .0 )cm s,两者比较有显著差异 (P <0 .0 1)。当门脉充血分数截定为 0 .0 7时 ,对出血预测敏感性 96 % ,特异性 76 %。结论　门脉充血分数、胃左静脉内径、食道曲张静脉内径及其血流速度对判断出血具有重要作用。