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71.
CGP 28 014 is a specific inhibitor of catechol-O-methyltransferase (COMT) in vivo. In humans, the inhibition was assessed by measuring urinary excretion of isoquinolines and with the levodopa test. Following administration of CGP 28 014, urinary excretion of isoquinolines was significantly increased. In rats, CGP 28 014 reduced plasma and striatal concentrations of 3-O-methyldopa (30MD) in a dose-dependent manner. Acute and subchronic administration of CGP 28 014 alone or in combination with the peripherally acting decarboxylase inhibitor benserazide decreased plasma 30MD as an index of COMT inhibition by about 50%. There seems to be a close relationship between the time-course of plasma concentrations of CGP 28 014 and the extent of COMT inhibition assessed by the 30MD/DOPA ratio in plasma.  相似文献   
72.
Abstract An oligonucleotide primer (ChInt) was synthesised from the variable internally transcribed spacer (ITS) 1 region of ribosomal DNA (rDNA) of Cylindrocarpon heteronema . PCR with primers ChInt and ITS4 (from a conserved sequence of the rDNA) amplified a 470-bp fragment from several isolates of C. heteronema but not from various apple wood saprophytes. Amplification of this fragment was achieved from 1–2 pg of fungal DNA. These primers amplified a fragment of the same size from DNA extracted from cankered wood but only after impurities were removed from the DNA on a Qiagen tip-5 column. Southern hybridization analysis confirmed the 470-bp fragment from C. heteronema DNA and cankered wood to be identical.  相似文献   
73.
Motivated by investigating the relationship between progesterone and the days in a menstrual cycle in a longitudinal study, we propose a multikink quantile regression model for longitudinal data analysis. It relaxes the linearity condition and assumes different regression forms in different regions of the domain of the threshold covariate. In this paper, we first propose a multikink quantile regression for longitudinal data. Two estimation procedures are proposed to estimate the regression coefficients and the kink points locations: one is a computationally efficient profile estimator under the working independence framework while the other one considers the within-subject correlations by using the unbiased generalized estimation equation approach. The selection consistency of the number of kink points and the asymptotic normality of two proposed estimators are established. Second, we construct a rank score test based on partial subgradients for the existence of the kink effect in longitudinal studies. Both the null distribution and the local alternative distribution of the test statistic have been derived. Simulation studies show that the proposed methods have excellent finite sample performance. In the application to the longitudinal progesterone data, we identify two kink points in the progesterone curves over different quantiles and observe that the progesterone level remains stable before the day of ovulation, then increases quickly in 5 to 6 days after ovulation and then changes to stable again or drops slightly.  相似文献   
74.
An in vitro test method for general metal toxicity screening was designed, based on the cellular response to stress. The expression of a transfected human growth hormone gene sequence driven by the human heat-shock protein 70 promoter in NIH/3T3 cells was used as marker of noxious contact with metal compounds. Out of a series of31 metals, 17 were competentfor inducing this stress response system. According to the effective concentration and to the intensity of the response, three different clusters of positive compounds emerged and were ranked as strong, intermediate strength and weak inducers. These results correlated well with data from other in vivo and in vitro metal toxicity studies, including LD50 in mice. Apparently the positivelnegative compounds also fitted well with data from genotoxicity and carcinogenesis studies on metal salts.Abbreviations hGH human growth hormone - hsp70 70 kDa heat-shock protein  相似文献   
75.
Summary For 25 Medicago sativa plants, measurements were made of in vitro pollen germination and growth and callus growth on mediums containing culture filtrate from two isolates of Fusarium oxysporum f. sp. medicaginis. In vivo resistance was determined by field inoculation with one isolate. There was no correlation between any in vitro measurement and in vivo resistance, and none of the in vitro measurements on control mediums were correlated. The only significant correlation for the same measurement between the two isolates was for pollen-tube length (r = 0.65). Percent of pollen germination was negatively correlated with callus growth for both isolates. Earlier work showed that callus growth in the presence of culture filtrate was linked to plant resistance, thus it appeared that percent pollen germination on culture filtrate had decreased for the more resistant plants. The haploid pollen may be used as a progeny test for identifying heterotic loci conferring resistance to Fusarium, but if the pollen of this plant species is used in direct selection by exposure to culture filtrate, the level of resistance to Fusarium may decrease.  相似文献   
76.
【背景】肺炎支原体是导致儿童和青少年呼吸道感染的重要病原体,长期以来由于其临床表现不特异而容易错过最佳治疗时期。【目的】结合多酶恒温扩增(multienzyme isothermal rapid amplification,MIRA)技术和核酸试纸条建立一种快速检测肺炎支原体的方法。【方法】以肺炎支原体社区获得性肺炎呼吸窘迫综合征(community acquired respiratory distress syndrome, CARDS)毒素编码基因为靶基因设计引物和探针,对反应体系的温度、时间等进行优化,评估其敏感性,通过检测肺炎支原体和其余7种病原体分析其特异性,并对35份临床样本进行验证。【结果】MIRA核酸试纸条法在37℃条件下,15 min内便可完成对肺炎支原体的检测,最低检出限为10 copies/μL;除肺炎支原体外,其余7种病原体均不能扩增,特异性较好。以实时荧光PCR检测为标准,MIRA核酸试纸条法对35份临床样本检测后的诊断特异度为100.00%、灵敏度为96.15%、阴性预测值为90.00%、阳性预测值为100.00%。【结论】本研究建立了MIRA核酸试纸条法...  相似文献   
77.
摘要 目的:探讨泌尿系造影联合彩色多普勒对小儿先天性肾积水的诊断价值。方法:选取2018年11月~2021年11月在本院治疗的88例先天性肾积水患儿为研究对象,所有患儿均完善静脉肾盂造影及彩色多普勒超声检查,以病理诊断结果为金标准,对比两种检查方法对小儿先天性肾积水的诊断价值。结果:彩色多普勒超声检查结果显示,肾积水轻度、中度、重度患儿分别为10例、39例、39例,不同病情程度患儿比较,重度组收缩期峰值速度(PSV)、舒张期最小流速(EDV)均低于中度组和轻度组,重度组血流阻力指数(RI)高于中度组和轻度组(P<0.05),但轻度组与中度组PSV、EDV、RI比较差异无统计学意义(P>0.05)。与病理学诊断检查结果对比,彩色多普勒超声对中度、重度先天性肾积水患儿具有较高的诊断效能,其准确度分别为90.91%、93.18%,与病理诊断kappa值分别为0.795、0.862,具有较高的一致性;但对轻度肾积水诊断效能较低,kappa值为0.629,一致性一般。静脉肾盂造影对轻度先天性肾积水患儿具有较高的诊断效能,准确度为96.59%,与病理诊断kappa值为0.824,具有较高的一致性;但对中度、重度肾积水诊断效能较低,kappa值分别为0.583、0.565,一致性一般。彩色多普勒超声联合静脉肾盂造影诊断准确率高达94.32%,明显高于两检查方法单独应用(P<0.05)。结论:不同病情程度的先天性肾积水患儿具有不同超声征象,彩色多普勒超声对中、重度肾积水患儿具有较好的诊断价值,而静脉肾盂造影诊断轻度肾积水患儿的效能较好,将二者联合可提高对先天性肾积水的诊断准确率。  相似文献   
78.
摘要 目的:探讨不同容量对胸段经椎间孔硬膜外注射(TFEI)药液扩散范围和镇痛效果的影响以及胸段TFEI用于诊断性阻滞的可行性。方法:选择2021年1月至2022年12月南京大学医学院附属鼓楼医院收治的胸段带状疱疹相关疼痛患者140例,随机分为4组,实施单次TFEI并分别注入不同容量含造影剂局麻药(A组:0.2 mL;B组:0.5 mL;C组:1.0 mL;D组:2 mL),CT扫描并观察造影剂在硬膜外向头侧、尾侧及总扩散节段,造影剂在椎间孔、同侧椎旁间隙、同侧及对侧硬膜外间隙扩散情况,判断是否为选择性神经根阻滞。评估注射前、注射后30分钟及24小时视觉模拟评分(VAS)。结果:头侧和尾侧扩散节段以及总扩散节段数,D组最多,A组最少(P<0.05);C组、D组造影剂扩散≥3个节段发生率明显高于B组(P<0.05);C组、D组病例造影剂扩散至同侧椎旁间隙和对侧硬膜外间隙的发生率明显高于A组、B组(P<0.05),仅A组37.1%的病例实现选择性神经根阻滞,其余各组均无选择性阻滞病例。注射后30分钟,C、D组VAS评分显著低于A、B组(P<0.05);注射后24小时,D组VAS评分显著低于A、B组(P<0.05)。结论:胸段带状疱疹相关疼痛患者TFEI药液扩散范围随注射容量的增加而扩大,且在硬膜外倾向于头侧扩散,2 mL容量单次TFEI可阻滞3个以上的神经节段,获得良好的镇痛效果。胸段TFEI行诊断性阻滞的可行性较差。  相似文献   
79.
摘要 目的:探讨经阴道三维超声联合糖类抗原125(CA125)、糖类抗原199(CA199)、中性粒细胞/淋巴细胞比值(NLR)及血小板/淋巴细胞比值(PLR)检测对绝经后女性子宫内膜癌(EC)的诊断效能。方法:回顾性分析本院2019年5月至2022年5月收治的因绝经后出血就诊的92例疑似子宫内膜肿瘤患者的病历资料,经手术病理证实,EC患者48例(EC组)、子宫内膜良性病变患者44例(良性组)。比较两组CA125、CA199、NLR及PLR水平,对比两组子宫内膜血管指数(VI)、血流指数(FI)、血管-血流指数(VFI)、子宫内膜容积(EV)变化及血流信号分布情况。绘制受试者工作特征(ROC)曲线分析经阴道三维超声联合CA125、CA199、NLR及PLR检测对绝经后EC的诊断效能。结果:EC组CA125、CA199、NLR及PLR水平均高于良性组(P<0.05)。EC组三维超声参数VI、FI、VFI及EV均高于良性组(P<0.05)。EC组血流信号Ⅱ级占比25.00%,Ⅲ级占比70.83%;良性组血流信号Ⅱ级占比88.64%,Ⅲ级占比2.27%。EC组血流信号Ⅱ级占比低于良性组,血流信号Ⅲ级占比高于良性组(P<0.05)。两组血流信号0级、Ⅰ级比较无差异(P>0.05)。ROC结果显示五项检查联合检测曲线下面积(AUC)值为0.944(95%Cl:0.902~0.985),具有更优的诊断效能(敏感度为89.10%、特异度为91.80%)。结论:CA125、CA199、NLR及PLR检测联合经阴道三维超声检查诊断绝经后EC效果显著,可为临床诊断提供参考。  相似文献   
80.
Dow and Cheverud (Am. J. Phys. Anthropol. 68:367–373, 1985) have published a statistical test for comparing any three similarity matrices. Using both simulations and analytical arguments, I establish that the presence of spatial autocorrelation, a common feature of geographically based anthropological and biological data, causes this test to reject too often. Increasing the spatial autocorrelation increases the spurious rejection rate. About 20% of the papers that reference Dow and Cheverud's paper have used their test with spatially autocorrelated data. Mantel's (Cancer Res. 27:209–220, 1967) method, when used as a test of spatial autocorrelation, is unaffected by these considerations, since its null hypothesis is that the data are uncorrelated. © 1992 Wiley-Liss, Inc.  相似文献   
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