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1.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   
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Epidermolysis bullosa simplex (EBS) is a skin fragility disorder resulting from mutations of structural proteins in the epidermis. We provide a brief report of long‐term survival and reproduction in a mother with EBS due to keratin 5 (KRT5) c.1429G > A (p.E477K) mutation, which causes a particularly severe form of the disease.  相似文献   
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Willeke  V. M.  Anderson  M. P.  Mahadevan  A.  Rojas  R.  Bhadelia  R.  Thomas  A. J.  Kasper  E. M. 《Journal of neuro-oncology》2020,147(2):247-260
Purpose

Epstein Barr virus (EBV)-associated smooth muscle tumors (SMT) in the central nervous system are rare tumors. EBV-associated SMT mainly occur in patient with compromised immune status. We report on a case of a HIV positive patient, who developed multiple EBV-SMTs, intracranially and in the spine. We systematically review the literature on the topic.

Case report

A 46 years old female with HIV was imaged for complaints of headaches for 2 years, when an intracranial lesion was found. The patient was followed with sequential MRI scans before an excision was performed 5 years later. Pathology revealed an EBV-associated SMT. Multiple other lesions appearing in the brain and in the spine over years were treated by stereotactic radiosurgery or by surgery. At the time of this report, the patient is alive under HARRT treatment without recurrence.

Methods

A systematic PRISMA guided literature research was conducted on the topic reviewing multiple databases for EBV-associated SMT located in brain or spine. We identified 52 patients from the literature and performed a pooled analysis.

Results

All patients in this cohort except one were immuno-suppressed from HIV, post-transplant therapy or because of CIS. Female predominance and a median age of 35 years was identified as was frequent multifocality. Therapeutic strategies varied but were mostly multidisciplinary with surgery.

Conclusion

Based on our results, EBV-associated SMT should be included in the differential diagnosis of intracranial lesions mimicking meningiomas in immuno-suppressed patients. Stereotactic radiosurgery can be offered as an alternate treatment option for suitable lesions. Long-term surveillance via MRI scanning is recommended for follow up.

  相似文献   
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ABSTRACT

Abortion is legal in South Africa, but negative abortion attitudes remain common and are poorly understood. We used nationally representative South African Social Attitudes Survey data to analyze abortion attitudes in the case of fetal anomaly and in the case of poverty from 2007 to 2016 (n = 20,711; ages = 16+). We measured correlations between abortion attitudes and these important predictors: religiosity, attitudes about premarital sex, attitudes about preferential hiring and promotion of women, and attitudes toward family gender roles. Abortion acceptability for poverty increased over time (b = 0.05, p < .001), but not for fetal anomaly (b = ?0.008, p = .284). Highly religious South Africans reported lower abortion acceptability in both cases (Odds Ratio (OR)anomaly = 0.85, p = .015; ORpoverty = 0.84, p = .02). Premarital sex acceptability strongly and positively predicted abortion acceptability (ORanomaly = 2.63, p < .001; ORpoverty = 2.46, p < .001). Attitudes about preferential hiring and promotion of women were not associated with abortion attitudes, but favorable attitudes about working mothers were positively associated with abortion acceptability for fetal anomaly ((ORanomaly = 1.09, p = .01; ORpoverty = 1.02, p = .641)). Results suggest negative abortion attitudes remain common in South Africa and are closely tied to religiosity, traditional ideologies about sexuality, and gender role expectations about motherhood.  相似文献   
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Congenital heart disease is a rare but important finding in adults who experience sudden death. Examination of the congenitally malformed heart has historically been considered esoteric and best left to those with expertise. The Cardiac Risk in the Young cardiovascular pathology laboratory based at St George's University of London has now received over 6,000 cases. Of these, 21 congenitally malformed hearts were retained for research and educational purposes. Hearts were assessed using sequential segmental analysis, and causes of death were adjudicated based on thorough macroscopic examination and histology. Congenital malformations that were encountered included atrial septal defects, ventricular septal defects, tetralogy of Fallot, and transposition of the great arteries in both its regular and congenitally corrected variants. Findings also included hearts with mirror-imaged and isomeric atrial appendages. Direct causes of death included myocardial fibrosis, pulmonary hypertension, and hemorrhage. A small but notable proportion did not reveal a substrate for arrhythmia, raising the question of whether the terminal event was due to the congenital heart disease itself, or an underlying channelopathy. Here, we demonstrate the value of simple sequential segmental analysis in describing and categorizing the cases, with the concept of the “morphological method” serving to identify the distinguishing features of the cardiac components. Clin. Anat. 33:394–404, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
9.
腹腔镜胆总管切开探查取石46例报告   总被引:1,自引:0,他引:1  
目的探讨腹腔镜胆总管切开探查取石、胆总管一期缝合的可行性及其微创价值。方法回顾分析我院46例腹腔镜胆总管切开探查取石的临床资料。腹腔镜下完成手术44例,其中胆总管切开探查取石胆总管一期缝合24例,胆总管切开探查取石胆总管T管引流20例;中转开腹胆总管切开取石T管引流2例。结果手术中无副损伤。手术后无胆漏及其它并发症发生。所有病例是治愈出院。32例术后随访3~12个月,未发现残余结石及胆道狭窄。结论腹腔镜胆总管切开探查取石、胆总管一期缝合是可行的,而且具有极大的微创优势。  相似文献   
10.
山西省出生缺陷高发区土壤元素分布特征   总被引:6,自引:0,他引:6  
目的 了解出生缺陷高发区土壤中元素分布特征,为出生缺陷的干预和治疗提供理论依据.方法 于2005年1-5月,选择山西省吕梁山区出生缺陷高发的中阳县和交口县作为出生缺陷高发区,以人口相对集中的河道两侧为采样点,共涉及8个乡镇,79个行政村;选择晋中盆地出生缺陷低发的祁县作为出生缺陷对照区,采样点均匀分布,共涉及6个乡镇,27个行政村.采集距耕地表层10~20cm深的土壤,共采集样品131件.采用ICP-电感耦合等离子发射光谱法,对土壤样品中的16种元素进行测定.结果 高发区土壤中元素总量明显高于低发区.与祁县相比,交口县土壤中元素含量偏高的有As、Mo、Pb、Ni、V,含量偏低的元素有Se,差异均有统计学意义(P<0.05);中阳县土壤中含量偏高的元素为Sn、Se、Mo、Zn、Sr、Pb、Ni、Fe、V、Ca、Cu、Al,偏低的元素为Mg和Na,差异均有统计学意义(P<0.05).土壤中元素含量(μg/g)与出生缺陷发病率的(1/万)逐步回归分析显示,交口县土壤中Mo、Al、As、Ni、Pb、Zn元素对病情影响有统计学意义(均P<0.01),其标准的逐步回归判别方程为:y=-1.321 1.106 Mo-0.509 Al 0.117 As 0.663 Ni-0.429 Pb-0.262 Zn(R2a=0.891);中阳县土壤中Pb、Mg、Ca、Al、Zn元素对病情影响有统计学意义(均P<0.05),其标准回归方程为:y=-1.757 0.441 Pb-0.264Mg 0.309 Ca-0.186Al 0.162Zn (R2a2=0.839).结论 交口县和中阳县土壤中Pb、Mo、Al等含量异常可能是两县出生缺陷高发的原因之一.  相似文献   
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