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31.
Objective: Meta-analysis was used to synthesize results of studies on emotional consequences of predictive genetic testing for BRCA1/2 mutations conferring increased risk of breast and ovarian cancer. Design: Studies assessing anxiety or cancer-specific distress before and after provision of test results (k = 20) were analyzed using a random-effects model. Moderator variables included country of data collection and personal cancer history of study participants. Main Outcome Measures: Standardized mean gain effect sizes were calculated for mutation carriers, noncarriers, and those with inconclusive results over short (0–4 weeks), moderate (5–24 weeks), or long (25–52 weeks) periods of time after testing. Results: Distress among carriers increased shortly after receiving results and returned to pretesting levels over time. Distress among noncarriers and those with inconclusive results decreased over time. Some distress patterns differed in studies conducted outside the United States and for individuals with varying cancer histories. Conclusion: Results underscore the importance of time; changes in distress observed shortly after test-result disclosure frequently differed from the pattern of distress seen subsequently. Although emotional consequences of this testing appear minimal, it remains possible that testing may affect cognitive and behavioral outcomes, which have rarely been examined through meta-analysis. Testing may also affect understudied subgroups differently. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
32.
Comments on the article by Richter entitled "Rats, Man, and the Welfare State" (see record 1960-02810-001). The commenter notes that in his article Richter did not indicate how hereditary and environmental factors were controlled. In comparing the hereditary survival characteristics of wild versus domesticated rats, it would be essential that the environmental influences on the survival characteristics of the wild rats should be ruled out. Another factor to be considered is that the wild state may offer a diet and other environmental influences, which in the life of a single individual would produce organic changes, accounting for some of the differences between wild and domestic rats. It would seem that the most effective way to determine the hereditary differences between wild and domestic rats would be to create a wild group, composed solely of the offspring of wild rats. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
Louise E. Simcox Laura Ormesher Clare Tower Ian A. Greer 《International journal of molecular sciences》2015,16(12):28418-28428
There is a paucity of strong evidence associated with adverse pregnancy outcomes and thrombophilia in pregnancy. These problems include both early (recurrent miscarriage) and late placental vascular-mediated problems (fetal loss, pre-eclampsia, placental abruption and intra-uterine growth restriction). Due to poor quality case-control and cohort study designs, there is often an increase in the relative risk of these complications associated with thrombophilia, particularly recurrent early pregnancy loss, late fetal loss and pre-eclampsia, but the absolute risk remains very small. It appears that low-molecular weight heparin has other benefits on the placental vascular system besides its anticoagulant properties. Its use is in the context of antiphospholipid syndrome and recurrent pregnancy loss and also in women with implantation failure to improve live birth rates. There is currently no role for low-molecular weight heparin to prevent late placental-mediated complications in patients with inherited thrombophilia and this may be due to small patient numbers in the studies involved in summarising the evidence. There is potential for low-molecular weight heparin to improve pregnancy outcomes in women with prior severe vascular complications of pregnancy such as early-onset intra-uterine growth restriction and pre-eclampsia but further high quality randomised controlled trials are required to answer this question. 相似文献
34.
Francesco Callea Paolo Tom Emanuele Bellacchio 《International journal of molecular sciences》2021,22(13)
In this article, we review the biological and clinical implication of the Recruitment-Secretory Block (“R-SB”) phenomenon. The phenomenon refers to the reaction of the liver with regard to protein secretion in conditions of clinical stimulation. Our basic knowledge of the process is due to the experimental work in animal models. Under basal conditions, the protein synthesis is mainly carried out by periportal (zone 1) hepatocytes that are considered the “professional” synthesizing protein cells. Under stimulation, midlobular and centrolobular (zones 2 and 3) hepatocytes, are progressively recruited according to lobular gradients and contribute to the increase of synthesis and secretion. The block of secretion, operated by exogenous agents, causes intracellular retention of all secretory proteins. The Pi MZ phenotype of Alpha-1-antitrypsin deficiency (AATD) has turned out to be the key for in vivo studies of the reaction of the liver, as synthesis and block of secretion are concomitant. Indeed, the M fraction of AAT is stimulated for synthesis and regularly exported while the Z fraction is mostly retained within the cell. For that reason, the phenomenon has been designated “Recruitment-Secretory Block” (“R-SB”). The “R-SB” phenomenon explains why: (a) the MZ individuals can correct the serum deficiency; (b) the resulting immonohistochemical and electron microscopic (EM) patterns are very peculiar and specific for the diagnosis of the Z mutation in tissue sections in the absence of genotyping; (c) the term carrier is no longer applicable for the heterozygous condition as all Pi MZ individuals undergo storage and the storage predisposes to liver damage. The storage represents the true elementary lesion and consequently reflects the phenotype-genotype correlation; (d) the site and function of the extrahepatic AAT and the relationship between intra and extracellular AAT; (e) last but not least, the concept of Endoplasmic Reticulum Storage Disease (ERSD) and of a new disease, hereditary hypofibrinogenemia with hepatic storage (HHHS). In the light of the emerging phenomenon, described in vitro, namely that M and Z AAT can form heteropolymers within hepatocytes as well as in circulation, we have reviewed the whole clinical and experimental material collected during forty years, in order to evaluate to what extent the polymerization phenomenon occurs in vivo. The paper summarizes similarities and differences between AAT and Fibrinogen as well as between the related diseases, AATD and HHHS. Indeed, fibrinogen gamma chain mutations undergo an aggregation process within the RER of hepatocytes similar to AATD. In addition, this work has clarified the intriguing phenomenon underlying a new syndrome, hereditary hypofibrinogenemia and hypo-APO-B-lipoproteinemia with hepatic storage of fibrinogen and APO-B lipoproteins. It is hoped that these studies could contribute to future research and select strategies aimed to simultaneously correct the hepatocytic storage, thus preventing the liver damage and the plasma deficiency of the two proteins. 相似文献
35.
一例点状掌跖角皮病大家系致病基因精细定位 总被引:1,自引:0,他引:1
目的在1例四代点状掌跖角皮病大家系中定位其致病基因所在区域。方法用覆盖8和15号染色体的微卫星标记对一例点状掌跖角皮病大家系进行致病基因的定位研究,用ABI3730测序仪进行微卫星标记的基因分型,利用Linkage软件(5.10 Version)和Cyrillic软件(2.01 Version)进行连锁和单倍型分析。结果该家系符合常染色体显性遗传模式,当外显率为100%时,排除了以前报道过的8q24.13-8q24.21区域,但在15号染色体上的微卫星标记D15S153处获得最大LOD值为5.38(重组率θ=0.00)。单倍型分析将该家系致病基因定位在微卫星标记D15S651和D15S988之间,该结果将国外定位的区域缩小至染色体15q22.2-15q22.31区域之间遗传距离为5.06cm内。结论染色体15q22.2-15q22.31区域存在该点状掌跖角皮病家系的致病基因,表明在中国人群中该病有遗传异质性存在。 相似文献
36.
为了研究quiverΔ上的A-广义路代数R=k(Δ,A),基于本原正交幂等元完全集,给出了广义路代数R=k(Δ,A)的不可分解投射模与内射模以及单模的构造形式.基于遗传代数性质得到了广义路代数是遗传代数的充要条件,并进一步在同调理论和有限维代数的Hochschild上同调的基础上得到了广义路代数的Hochschild上同调. 相似文献
37.
提出了基于遗传算法的感应电动机调速系统PID参数的寻优方法,并利用优化后的PID控制器作为感应电动机双闭环调速系统的转速调节器进行仿真分析。研究表明,利用遗传算法寻优设计的PID控制器来控制感应电动机,可以获得良好的稳定性、鲁棒性和动态品质。 相似文献
38.
Alport综合征(Alport syndrome,AS)是一种遗传进行性肾病。本文对32例AS患者肾脏的超微结构进行病理观察,并结合其临床表现、HE、特殊染色(PAS、PAM-Masson)、免疫组化(IgG、IgM、IgA、C3c、HBsAg、HBcAg)结果进行分析。患者多以浮肿、肉眼血尿就诊,中位年龄12岁。5例有家族史,4例患者曾做过肾穿刺活检,6例有治疗史。肾活检组织光镜及免疫组化检查无特异性表现。电镜下肾小球基底膜出现特征性的厚薄不均及分层撕裂。肾小管和Bowman氏囊壁上皮细胞及小动脉壁内皮细胞也可查见分层撕裂。AS在电镜下的特异性超微结构改变在病理诊断中具有重要诊断价值。 相似文献
39.
Priya Jarwar Shakeel Ahmed Sheikh Yar Muhammad Waryah Ikram Uddin Ujjan Saima Riazuddin Ali Muhammad Waryah Zubair M. Ahmed 《International journal of molecular sciences》2021,22(19)
Hereditary congenital cataract (HCC) is clinically and genetically heterogeneous. We investigated HCC that segregates in three inbred families (LUCC03, LUCC16, and LUCC24). Ophthalmological examinations revealed cataracts with variability related to the age of onset segregating in a recessive manner in these families. Exome sequencing of probands identified a novel homozygous c.2710delG;p.(Val904Cysfs*36) EPHA2 variant in LUCC03 and a known homozygous c.2353G>A;p.(Ala785Thr) EPHA2 variant in the other two recessive families. EPHA2 encodes a transmembrane tyrosine kinase receptor, which is primarily involved in membrane-transport, cell-cell adhesion, and repulsion signaling processes. Computational structural modeling predicts that substitution of a threonine for an alanine p.(Ala785Thr) results in the formation of three new hydrogen bonds with the neighboring residues, which causes misfolding of EPHA2 in both scenarios. Insights from our study will facilitate counseling regarding the molecular and phenotypic landscape of EPHA2-related HCC. 相似文献
40.
Raquel Martínez-Pulleiro María García-Murias Manuel Fidalgo-Díaz Miguel ngel García-Gonzlez 《International journal of molecular sciences》2021,22(20)
Alport syndrome is a genetic and hereditary disease, caused by mutations in the type IV collagen genes COL4A3, COL4A4 and COL4A5, that affects the glomerular basement membrane of the kidney. It is a rare disease with an underestimated prevalence. Genetic analysis of population cohorts has revealed that it is the second most common inherited kidney disease after polycystic kidney disease. Renal involvement is the main manifestation, although it may have associated extrarenal manifestations such as hearing loss or ocular problems. The degree of expression of the disease changes according to the gene affected and other factors, known or yet to be known. The pathophysiology is not yet fully understood, although some receptors, pathways or molecules are known to be linked to the disease. There is also no specific treatment for Alport syndrome; the most commonly used are renin–angiotensin–aldosterone system inhibitors. In recent years, diagnosis has come a long way, thanks to advances in DNA sequencing technologies such as next-generation sequencing (NGS). Further research at the genetic and molecular levels in the future will complete the partial vision of the pathophysiological mechanism that we have, and will allow us to better understand what is happening and how to solve it. 相似文献