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排序方式: 共有445条查询结果,搜索用时 15 毫秒
1.
Mariani E Roda P Mariani AR Vitale M Degrassi A Papa S Manzoli FA Facchini A 《Cytotechnology》1987,1(1):103-105
Old subjects exhibit a decline in circulating T cells and an impaired proliferative response to mitogens, plus a relative increase in cells with NK phenotype not associated with a concomitant increase in their cytolitic activity.In the present study a limiting dilution assay was used to evaluate the phenotype, the functional activity and the proliferative capacity of clones obtained from peripheral blood lymphocytes of old and young subjects. CD5+ CD8+ clones from old people showed a significant impairment in their proliferative capacity and a decreased lytic activity against K562 and P815-IgG cell lines. 相似文献
2.
Mario Marini Gianna Roscetti Lucilla Bongiorno Alessandra Urbani L. Giorgio Roda 《Neurochemical research》1990,15(1):61-67
Seven groups of enkephalin-degrading enzymes and three groups of inhibitors active on these enzymes were separated from human plasma. The activity of the enzymes in hydrolyzing enkephalins and of the inhibitors in protecting enkephalins from proteolysis was measured. Results obtained with the endogenous inhibitors were compared to those relative to synthetic inhibitors. Data obtained indicate that all enkephalin-degrading enzymes found in plasma are significantly inhibited by the endogenous substances present in this tissue. The inhibition of the different classes of plasma enzymes by two of the three groups of endogenous substances is quite uniform, while one group of inhibitors appears specific to dipeptidylpeptidases. Results obtained are discussed in terms of the functional role of the inhibitory substances and of the possible pharmacological implication of their presence in human plasma. 相似文献
3.
Shafiq Fahad Iqbal Muhammad Raza Syed Hammad Akram Nudrat Aisha Ashraf Muhammad 《Journal of Plant Growth Regulation》2023,42(3):1267-1290
Journal of Plant Growth Regulation - Fullerenols are carbon nanoparticles that have been declared as free radical sponges. There is a need to take a prudent path toward its applications in various... 相似文献
4.
A M Morselli E Roda A Roda C Sama R Aldini G Mazzella D Festi F Bazzoli E Sarti L Barbara 《Bollettino della Società italiana di biologia sperimentale》1979,55(15):1527-1533
A multicompartmental model was applied to the study of the plasmatic and biliary kinetics of the 14C-Cholic acid intravenously injected into a baboon in normal and cholestatic condition. For the evaluation of transfer rates FORTAN IV procedures were used, utilizing Powell method. The degree of fitting was: in normal condition in serum 7% for free and 35% for conjugated Cholic acid, while in bile 5% and 4% respectively; in serum in cholestatic condition 7% for free and 12% for conjugates. The high degree of fitting and reliable estimation of transfer rates suggest that the multicompartmental model applied represents most likely the physio-pathological conditions studied. 相似文献
5.
A sensitive and specific radioimmunoassay for glycine and taurine conjugates of lithocholic acid (CLCA) has been developed. 3H-glycolithocholic acid (S.A. = 17Ci/mmol) was used as tracer. Separation of free from antibody-bound bile acid was carried out using ammonium sulphate (saturated solution). The antiserum showed high specificity for both glyco and tauro conjugated lithocholate (100% cross reaction) and lithocholic acid (25% cross reaction). The sensitivity of the assay (1 pmole/tube), was adequate for measuring CLCA in peripheral blood and hepatic tissue in man. 相似文献
6.
Enkephalin-binding systems in human plasma 总被引:1,自引:0,他引:1
Roberta Possenti Valeria De Marco Ornella Cherubini L. Giorgio Roda 《Neurochemical research》1983,8(4):423-432
Three amino acid-containing fractions present in human plasma are shown to bind both leu and met-enkephalin: serum albumin and two species of a much lower molecular weight, in all likelihood polypeptides. The amount of enkephalin associated with serum albumin seems comparatively smaller than that associated with the two low molecular weight systems. These systems jointly are apparently capable of binding a significant part of the circulating enkephalins. The possibility is suggested that the interactions described may play a role in maintaining the integrity of circulating enkephalins. 相似文献
7.
Amol A. Verma Tejasvi Hora Hae Young Jung Michael Fralick Sarah L. Malecki Lauren Lapointe-Shaw Adina Weinerman Terence Tang Janice L. Kwan Jessica J. Liu Shail Rawal Timothy C.Y. Chan Angela M. Cheung Laura C. Rosella Marzyeh Ghassemi Margaret Herridge Muhammad Mamdani Fahad Razak 《CMAJ》2021,193(23):E859
8.
Missing data are unavoidable in environmental epidemiologic surveys. The aim of this study was to compare methods for handling large amounts of missing values: omission of missing values, single and multiple imputations (through linear regression or partial least squares regression), and a fully Bayesian approach. These methods were applied to the PARIS birth cohort, where indoor domestic pollutant measurements were performed in a random sample of babies'' dwellings. A simulation study was conducted to assess performances of different approaches with a high proportion of missing values (from 50% to 95%). Different simulation scenarios were carried out, controlling the true value of the association (odds ratio of 1.0, 1.2, and 1.4), and varying the health outcome prevalence. When a large amount of data is missing, omitting these missing data reduced statistical power and inflated standard errors, which affected the significance of the association. Single imputation underestimated the variability, and considerably increased risk of type I error. All approaches were conservative, except the Bayesian joint model. In the case of a common health outcome, the fully Bayesian approach is the most efficient approach (low root mean square error, reasonable type I error, and high statistical power). Nevertheless for a less prevalent event, the type I error is increased and the statistical power is reduced. The estimated posterior distribution of the OR is useful to refine the conclusion. Among the methods handling missing values, no approach is absolutely the best but when usual approaches (e.g. single imputation) are not sufficient, joint modelling approach of missing process and health association is more efficient when large amounts of data are missing. 相似文献
9.
Shi Zhenjie Zheng Qianjiao Sun Xiaoyang Xie Fuchun Zhao Jian Zhang Gaoyun Zhao Wei Guo Zhixin Ariunzul Ariuka Fahad Shah Adnan Muhammad Qin Dong Saud Shah Yajun Chen 《BMC plant biology》2020,20(1):1-15
Kernel weight and morphology are important traits affecting cereal yields and quality. Dissecting the genetic basis of thousand kernel weight (TKW) and its related traits is an effective method to improve wheat yield. In this study, we performed quantitative trait loci (QTL) analysis using recombinant inbred lines derived from the cross ‘PuBing3228 × Gao8901’ (PG-RIL) to dissect the genetic basis of kernel traits. A total of 17 stable QTLs related to kernel traits were identified, notably, two stable QTLs QTkw.cas-1A.2 and QTkw.cas-4A explained the largest portion of the phenotypic variance for TKW and kernel length (KL), and the other two stable QTLs QTkw.cas-6A.1 and QTkw.cas-7D.2 contributed more effects on kernel width (KW). Conditional QTL analysis revealed that the stable QTLs for TKW were mainly affected by KW. The QTLs QTkw.cas-7D.2 and QKw.cas-7D.1 associated with TKW and KW were delimited to the physical interval of approximately 3.82 Mb harboring 47 candidate genes. Among them, the candidate gene TaFT-D1 had a 1 bp insertions/deletion (InDel) within the third exon, which might be the reason for diversity in TKW and KW between the two parents. A Kompetitive Allele-Specific PCR (KASP) marker of TaFT-D1 allele was developed and verified by PG-RIL and a natural population consisted of 141 cultivar/lines. It was found that the favorable TaFT-D1 (G)-allele has been positively selected during Chinese wheat breeding. Thus, these results can be used for further positional cloning and marker-assisted selection in wheat breeding programs. Seventeen stable QTLs related to kernel traits were identified. The stable QTLs for thousand kernel weight were mainly affected by kernel width. TaFT-D1 could be the candidate gene for QTLs QTkw.cas-7D.2 and QKw.cas-7D.1. 相似文献
10.
Akram Nudrat Aisha Shafiq Fahad Ashraf Muhammad Iqbal Muhammad Ahmad Parvaiz 《Journal of Plant Growth Regulation》2021,40(3):891-905
Journal of Plant Growth Regulation - Plant biofibers are of great economic and commercial importance. Among various fiber producing crops, cotton (Gossypium hirsutum L.), hemp (Cannabis sativa L.),... 相似文献