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排序方式: 共有128条查询结果,搜索用时 15 毫秒
1.
OBJECTIVE--To ascertain whether the membership examination for the Royal College of General Practitioners (MRCGP) discriminates against doctors of Indian subcontinent ethnic origin ("Asian doctors"). DESIGN--Retrospective analysis of data from five administrations of the MRCGP examination (December 1988-December 1990). SETTING--United Kingdom national examination body. SUBJECTS--3686 doctors taking the examination for the first time, 244 of whom were classified as Asian, the remainder as non-Asian. MAIN OUTCOME MEASURES--Comparison of performance in each of the written and oral components of the examination between Asian doctors, identified by their names and classified into subgroups by countries of birth and primary medical training from data provided at registration, and non-Asian doctors. RESULTS--On written components of the examination (multiple choice paper mean score Asians versus non-Asians 42.3 v 48.6, modified essay paper 40.9 v 48.9, practice topic/critical reading paper 41.5 v 48.7, all p less than 0.001 by t testing). But analysis by countries of birth and primary training showed that these differences were due largely to poor performance by certain groups of Asian doctors, especially those born and trained in the Indian subcontinent or elsewhere outside the United Kingdom. Asian doctors born and trained in the United Kingdom and those born in Africa or the West Indies and trained in the United Kingdom performed similarly to the non-Asian doctors. CONCLUSIONS--The examination does not systematically discriminate against Asian doctors, but the poor performance of the two subgroups of Asians is cause for serious concern and requires investigation. 相似文献
2.
Quan Zhang Fengyun Chen Ansar Javeed Miaofeng Wang Ranran Si Jiaxing Li Bingnan Han 《化学与生物多样性》2023,20(6):e202300445
Development of suitable antimicrobial biomaterials for hygienic wound dressing and healing is an important requirement for medical application. Durable mechanical properties increase the application range of biomaterial in different environmental and biological conditions. Due to the inherent brittleness of silk fibroin (SF), polyurethane fiber (PUF) was used to modify SF containing actinomycin X2 (Ac.X2) to prepare silk fibroin@actinomycin X2/polyurethane fiber (ASF/PUF) blend membranes. The ASF/PUF blend membrane was developed by solution casting method. Incorporation of PUF improved the flexibility of material and introduction of Ac.X2 has increased antibacterial activity of materials. Excellent mechanical properties (tensile strength up to 25.7 MPa and elongation at break up to 946.5 %) of 50 % SF+50 % PUF blend membrane were proved by tensile testing machine. FT-IR spectra, TGA, contact angle and DMA were tested to prove the blend membrane's physico-chemical characteristics. ASF/PUF blend membrane displayed satisfactory antibacterial activity against S. aureus, and the cytotoxicity tests showed that the blend membrane has better biosafety compared to directly applied Ac.X2 in soluble form. These results suggest that the modification of SF through PUF for development of flexible antibacterial membranes has great potential application value in the field of silk-like material fabrication. 相似文献
3.
Control of circadian rhythm in nitrate reductase activity in Wolffia microscopica Griff 总被引:1,自引:0,他引:1
Bakshi Inderjeet Singh; Farooqi A. H. Abad; Maheshwari S. C. 《Plant & cell physiology》1979,20(5):957-963
In Wolffia microscopica, the activity of nitrate reductase showedstrong diurnal rhythmicity with a peak in the forenoon. Therhythmicity persists under extended dark conditions as wellas under continuous light. The phase of the rhythm shifts underinverted light-dark cycles. Studies with various inhibitorsof macromolecular synthesis suggest that the increase in enzymeactivity depends on the new synthesis of both RNA and protein. (Received February 14, 1979; ) 相似文献
4.
A modified mouse splenocyte culture system was standardized after testing different mitogens (i.e., phytohemagglutinin (PHA), concanavalin A (Con A)). The mitotic index was determined for comparison between different mitogens. Following selection of appropriate mitogen (PHA 16, Flow), a series of experiments were conducted to evaluate the application of a cytokinesis-block for scoring micronuclei and assays for chromosomal aberrations produced by treatment in G0 and G2 for the purposes of biological dosimetry following in vivo and/or in vitro exposure to X-rays, fission neutrons and bleomycin. In the X-irradiation studies, the frequencies of micronuclei and chromosomal aberrations (i.e., dicentrics and rings) increased in a dose-dependent manner. These data could be fitted to a linear-quadratic model. No difference was observed between irradiation in vivo and in vitro, suggesting that measurement of dicentrics and micronuclei in vitro after X-irradiation can be used as an in vivo dosimeter. Following in vivo irradiation with 1 MeV fission neutrons and in vitro culturing of mouse splenocytes, linear dose-response curves were obtained for induction of micronuclei and chromosomal aberrations. The lethal effects of neutrons were shown to be significantly greater than for a similar dose of X-rays. The relative biological effectiveness (RBE) was 6-8 in a dose range of 0.25-3 Gy for radiation-induced asymmetrical exchanges (dicentrics and rings), and about 8 for micronuclei in a dose range of 0.25-2 Gy. Furthermore, the induction of chromosomal aberrations by bleomycin was investigated in mouse G0 splenocytes (in vitro) and compared with X-ray data. Following bleomycin treatment (2 h) a similar pattern of dose-response curve was obtained as with X-rays. In this context a bleomycin rad equivalent of 20 micrograms/ml = 0.50 Gy was estimated. 相似文献
5.
6.
Francesca D’Addio Takuya Ueno Michael Clarkson Baogong Zhu Andrea Vergani Gordon J. Freeman Mohamed H. Sayegh Mohammed Javeed I. Ansari Paolo Fiorina Antje Habicht 《PloS one》2013,8(4)
CD160 is a cell surface molecule expressed by most NK cells and approximately 50% of CD8+ cytotoxic T lymphocytes. Engagement of CD160 by MHC class-I directly triggers a costimulatory signal to TCR-induced proliferation, cytokine production and cytotoxic effector functions. The role of CD160 in alloimmunity is unknown. Using a newly generated CD160 fusion protein (CD160Ig) we examined the role of the novel costimulatory molecule CD160 in mediating CD4+ or CD8+ T cell driven allograft rejection. CD160Ig inhibits alloreactive CD8+ T cell proliferation and IFN-γ production in vitro, in particular in the absence of CD28 costimulation. Consequently CD160Ig prolongs fully mismatched cardiac allograft survival in CD4−/−, CD28−/− knockout and CTLA4Ig treated WT recipients, but not in WT or CD8−/− knockout recipients. The prolonged cardiac allograft survival is associated with reduced alloreactive CD8+ T cell proliferation, effector/memory responses and alloreactive IFN-γ production. Thus, CD160 signaling is particularly important in CD28-independent effector/memory CD8+ alloreactive T cell activation in vivo and therefore may serve as a novel target for prevention of allograft rejection. 相似文献
7.
Aims
To assess the cognitive and behavioral aspects of executive functioning (EF) and learning skills in extremely preterm (EPT) children compared with term control children aged 10 to 15 years.Methods
A total of 132 of 134 (98% of all eligible survivors) EPT children born at the 2 Swedish regional tertiary care centers from 1992 to 1998 (mean age = 12 years, mean birth weight = 718 g, and mean gestational age = 24.4 weeks) and 103 matched term controls were assessed. General intelligence was assessed using the Wechsler Intelligence Scale for Children (WISC-III-R), and cognitive aspects of EF were analyzed using EF-sensitive subscales of the WISC-III-R and Tower test of the Delis-Kaplan Executive Function Scale (D-KEFS). Behaviors related to EF and learning skills were assessed using the Five to Fifteen questionnaire, which is a validated parent and teacher instrument. Academic performance in school was assessed by teachers’ responses on Achenbach’s Teachers Report Form. Analyses performed included multivariate analyses of covariance (ANCOVA and MANCOVA) and logistic regression analyses.Results
The EPT children displayed significant deficits in cognitive aspects of EF compared with the controls, exhibiting decreases on the order of 0.9 SD to 1.2 SD for tasks of verbal conceptual reasoning, verbal and non-verbal working memory, processing speed and planning ability (P <0.001 for all). After excluding the children with major neurosensory impairment (NSI) or a Full Scale intelligence quotient (FSIQ) of < 70, significant differences were observed on all tests. Compared with controls, parents and teachers of EPT children reported significantly more EF-related behavioral problems. MANCOVA of teacher-reported learning skills in children with FSIQ >70 and without major NSI revealed no interactions, but significant main effects were observed for the behavioral composite executive function score, group status (EPT vs control) and FSIQ, for which all effect sizes were medium to large. The corresponding findings of MANCOVA of the parent-reported learning skills were very similar. According to the teachers’ ratings, the EPT children were less well adjusted to the school environment.Conclusion
EPT children born in the 1990s who received active perinatal care are at an increased risk of executive dysfunction, even after excluding children with significant neurodevelopmental disabilities. Even mild to moderate executive dysfunctions has a significant impact on learning skills. These findings suggest the need for timely interventions that address specific cognitive vulnerabilities and executive dysfunctions. 相似文献8.
9.
Agatha A. van der Klaauw Sophie Croizier Edson Mendes de Oliveira Lukas K.J. Stadler Soyoung Park Youxin Kong Matthew C. Banton Panna Tandon Audrey E. Hendricks Julia M. Keogh Susanna E. Riley Sofia Papadia Elana Henning Rebecca Bounds Elena G. Bochukova Vanisha Mistry Stephen O’Rahilly Richard B. Simerly I. Sadaf Farooqi 《Cell》2019,176(4):729-742.e18
10.
Cumhur Gokhan Ekmekci Ender Coskunpinar Hakan Avci Ammad Ahmad Farooqi Kadir Serkan Orhan Fahri Akbas 《Journal of cellular biochemistry》2019,120(3):3415-3422
Larynx cancer is a therapeutically challenging disease. Rapidly evolving experimentally validated data have significantly improved our understanding of the complex role of numerous RNA, DNA, and proteins that play a role in the development and progression of cancer. Based on the insights from approximately two decades of research, it seems clear that microRNAs (miRNAs) have revolutionized our concepts related to the main role of noncoding RNAs in different cancers’ progression, development, and metastasis. Mechanistically, miRNAs have been reported to regulate different RNAs and finally protein-coding genes. The expression profiling of miRNAs and messenger RNA (mRNAs) was conducted for a deeper analysis of the miRNAs and mRNAs which play an essential role in larynx cancer. Downregulation or upregulation over twofolds in the miRNAs was considered to be significant, and that of sixfolds or below was considered to be significant for the mRNAs. In accordance with this approach, the expression levels of 43 miRNAs were increased in this study, whereas the expression levels of 129 were decreased. Accordingly, all the genomic expression studies provided evidence of upregulation of 97 genes, whereas 128 genes were found to be downregulated. Among these miRNAs, hsa-miR-20a-3p and hsa-miR-1972 were noted to be important in the etiology of larynx cancer. 相似文献