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71.
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73.
Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene 总被引:4,自引:0,他引:4
74.
Alcohol use disorders in persons with co-occurring psychiatric disorders are associated with high rates of psy-chosocial instability and poorer treatment outcomes. Thus, assessment of alcohol use and abuse should become an integral part of psychiatric care. Because setf-report-based measures are frequently used, issues of reliability and validity in this population should be critically examined. The purpose of this article is to review and critique the existing empirical literature that has evaluated the psychometric integrity of self- report-based measures in psychiatric settings, and to outline a research agenda that promises to enhance the accuracy of alcohol assessment by persons receiving psychiatric treatment. 相似文献
75.
T cell epitope spreading to myelin oligodendrocyte glycoprotein in HLA-DR4 transgenic mice during experimental autoimmune encephalomyelitis 总被引:2,自引:0,他引:2
Klehmet J Shive C Guardia-Wolff R Petersen I Spack EG Boehm BO Weissert R Forsthuber TG 《Clinical immunology (Orlando, Fla.)》2004,111(1):53-60
Epitope spreading has been implicated in the pathogenesis of experimental autoimmune encephalomyelitis (EAE) and human multiple sclerosis (MS). T cell epitope spreading has been demonstrated in rodents for myelin basic protein (MBP) and proteolipid protein (PLP) determinants, but not for myelin oligodendrocyte glycoprotein (MOG), another important myelin antigen. Moreover, the role of human autoimmunity-associated MHC molecules in epitope spreading, including HLA-DR2 and DR4, has not been formally examined. To address these questions, we investigated epitope spreading to MOG determinants in HLA-DR4 (DRB1*0401) transgenic mice during EAE. The data show that upon induction of EAE in HLA-DR4 transgenic mice with the immunodominant HLA-DR4-restricted MOG peptide 97-108 (MOG(97-108); TCFFRDHSYQEE), the T cell response diversifies over time to MOG(181-200) (core: MOG(183-191); FVIVPVLGP) and MBP. The spreading epitope MOG(181-200) binds with high affinity to HLA-DRB1*0401 and is presented by human HLA-DRB1*0401+antigen presenting cells. Moreover, this epitope is encephalitogenic in HLA-DRB1*0401 transgenic mice. This study demonstrates intra- and intermolecular epitope spreading to MOG and MBP in "humanized" HLA-DR4 transgenic mice. 相似文献
76.
Shannon G. Farmakis Ann M. Barnes John C. Carey Stephen R. Braddock 《American journal of medical genetics. Part A》2019,179(3):455-466
The purpose of this study was to determine whether trisomy 18 patients are at an increased risk of tumor development and require formal tumor screening recommendations. A literature search of trisomy 18 patients with reports of tumors or malignancies, and compilation of all previously reported as well as new unreported cases was performed. 67 patients with trisomy 18 were found to have documented malignancies. 44 patients had hepatoblastomas, 21 patients had Wilms tumors, one patient had a functional neurogenic neoplasia, and one patient had Hodgkins lymphoma. The increasing numbers of reported malignancies in patients with trisomy 18 supports the indication for an early screening process. Specific screening recommendations are outlined consisting of imaging exams and laboratory values performed at specific intervals. 相似文献
77.
阮强 《中华微生物学和免疫学杂志》1994,(5)
研究资料表明,人巨细胞病毒(HCMv)单一蛋白的单一抗原决定簇只能被部分患者阳性血清识别。组建在血清学诊断中能够替代全病毒抗原的基因工程抗原,需要含有病毒多种主要抗原蛋白的抗原决定簇。为搞清在表达载体中重复插入某一抗原决定簇基因是否能表达出更高抗原效价的融会蛋白,我们用点突变的方法,在表达载体中分别插入了人HCMv的ppUL32蛋白羧基端一个抗原决定簇基因的1个、2个和3个拷贝。在免疫转印检测中,这些克隆表达的融合蛋白与特异性阳性血清的反应性差别不明显。这表明,插入表达载体中目的基因的多寡对表达蛋白的抗原效价没有显著影响。 相似文献
78.
The University of Virginia School of Medicine has developed a student-initiated, faculty-assisted system to evaluate the faculty who teach the third-year clinical clerkships. All students complete an evaluation at the end of each clerkship, and the fourth-year class and student government compile the results and publish a detailed annual report of the data, offering constructive criticism and recommendations for change. Teaching faculty then review the report and respond to the student government, the faculty clerkship committee, and the student curriculum committee, addressing the contents of the report and initiating proposals to correct deficiencies and improve teaching. The experience of the first two administrations of this system (1988-1990) has been encouraging, and the authors suggest that the system will be applicable to the evaluation of clinical teaching on a universal basis. 相似文献
79.
Carey E. Uhlenkott Jeannette C. Huijzer Dawn J. Cardeiro Catherine A. Elstad Gary G. Meadows 《Clinical & experimental metastasis》1996,14(2):125-137
We previously reported that low levels of tyrosine (Tyr) and phenylalanine (Phe) alter the metastatic phenotype of B16-BL6 (BL6) murine melanoma and select for tumor cell populations with decreased lung colonizing ability. To more specifically characterize the effects of Tyr and Phe restriction on the malignant phenotype of BL6, we investigated in vitro attachment, invasion, proteinase expression, and chemotaxis of high and low metastatic BL6 variants. High metastatic variant cells were isolated from subcutaneous tumors of mice fed a nutritionally complete diet (ND cells) and low metastatic variant cells were isolated from mice fed a diet restricted in Tyr and Phe (LTP cells). Results indicate that attachment to reconstituted basement membrane (Matrigel) was significantly reduced in LTP cells as compared to ND cells. Attachment to collagen IV, laminin, and fibronectin were similar between the two variants. Invasion through Matrigel and growth factor-reduced Matrigel were significantly decreased in LTP cells as compared to ND cells. Zymography revealed the presence of M
r 92 000 and M
r 72 000 progelatinases, tissue plasminogen activator, and urokinase plasminogen activator in the conditioned medium of both variants; however, there were no differences in activity of these secreted proteinases between the two variants. Growth of the variants on growth factor-reduced Matrigel similarly induced expression of the M
r 92 000 progelatinase. The variants exhibited similar chemotactic responses toward laminin. However, the chemotactic response toward fibronectin by LTP cells was significantly increased. MFR5, a monoclonal antibody which selectively blocks function of the 5 chain of the 5ß1 integrin, VLA-5, decreased the chemotactic response toward fibronectin of ND cells by 37%; the chemotactic response by LTP cells was reduced by 49%. This effect was specific for fibronectin-mediated chemotaxis since the chemotaxis toward laminin and invasion through Matrigel were not altered by the presence of MFR5. The surface expression of VLA-5 was significantly increased in LTP cells as compared to ND cells by flow cytometric analysis. These observations suggest that limitation of Tyr and Phe either directly modifies BL6 or selects for subpopulations with altered in vitro invasion, chemotaxis, and integrin expression. 相似文献
80.
Varicocele--the most common cause of male factor infertility? 总被引:5,自引:0,他引:5
Varicocele is often cited as the most common cause of male factor infertility. Arguments in support of this statement include reports of increased prevalence of varicocele in populations of infertile men compared with fertile or otherwise unselected men, association of varicocele with abnormal semen parameters, and improvements in semen parameters and/or pregnancy rates after varicocele repair. Logically, there would appear to be three possibilities regarding the relationship between varicocele and fertility: (i) varicocele has no association with or effect on male fertility; (ii) varicocele may be associated with, but is not the cause of, male subfertility; and (iii) varicocele is a direct cause of male subfertility. In the following, we review evidence from the literature for and against these three possibilities: at the current time, available evidence appears inadequate to confirm or deny any of these three possibilities. Since the ultimate goal of infertile couples is to conceive, it seem logical that future varicocele research should focus primarily on adequately powered, controlled clinical trials in well-characterized infertile couples, randomized to intervention or appropriate controlled observation, with pregnancy as the primary outcome. 相似文献