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《Annals of epidemiology》2014,24(5):376-382
PurposeThe reproductive windows between age at menarche and age at first birth (standardized age at first birth) and from menarche to menopause (reproductive lifespan) may interact with genetic variants in association with breast cancer risk.MethodsWe assessed this hypothesis in 6131 breast cancer cases and 7274 controls who participated in the population-based Collaborative Breast Cancer Study. Risk factor information was collected through telephone interviews, and DNA samples were collected on a subsample (N= 1484 cases, 1307 controls) to genotype for 13 genome-wide association study-identified loci. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were calculated, and P values for the interaction between reproductive windows and genotypes were obtained by adding cross-product terms to statistical models.ResultsFor standardized age at first birth, the OR was 1.52 (CI, 1.36–1.71) comparing the highest quintile with the lowest quintile. Carrier status for rs10941679 (5p12) and rs10483813 (RAD51B) appeared to modify this relationship (P = .04 and P = .02, respectively). For reproductive lifespan, the OR comparing the highest quintile with the lowest quintiles was 1.62 (CI, 1.35–1.95). No interactions were detected between genotype and reproductive lifespan (all P > .05). All results were similar regardless of ductal versus lobular breast cancer subtype.ConclusionsOur results suggest that the reproductive windows are associated with breast cancer risk and that associations may vary by genetic variants.  相似文献   
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嗜酸细胞性胃肠炎临床分析   总被引:6,自引:0,他引:6  
嗜酸细胞性胃肠炎(EG)是一种少见的良性消化道疾病,临床表现无特异性,误诊率较高。目的:通过对EG的一般情况、发病诱因、临床表现、辅助检查、诊断分型、误诊情况以及治疗和预后进行分析,以提高对该病的认识,避免误诊误治,减少患者痛苦。方法:对中国人民解放军总医院消化疾病中心的4例EG以及以“嗜酸细胞。胃肠炎”为关键词在中国医院知识仓库医学专题全文数据库(CHKD)中检索得到的1997~2007年发表的文献中169例EG的临床特点进行分析。结果:本组资料显示,44.5%的EG与过敏有关,常见临床表现为腹痛(94,2%)、腹泻(60.7%)、恶心(56.1%)、呕吐(51.5%)、腹胀(38-2%)、腹水(28.3%)。嗜酸性粒细胞(EOS)升高在外周血、骨髓和腹水中的阳性率分别为74.0%、98,2%和90.3%。胃镜和结肠镜黏膜活检发现EOS浸润胃黏膜和肠黏膜分别占88-2%和64.6%。诊断以黏膜型EG最为多见(65.3%),误诊率为40.5%。77.5%的EG患者接受糖皮质激素治疗,疗效良好。结论:EG是一种易误诊的少见病。临床表现无特异性,确诊应从提高对该病的认识、适时行血常规、骨髓和腹水EOS检查、胃肠道黏膜活检病理检查等方面人手。糖皮质激素治疗EG有效,预后良好。  相似文献   
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PURPOSE: Stercoral perforation of the colon is reported to be a rare disease with poor prognosis. The aim of this study was to determine the frequency of stercoral perforation of the colon, to define diagnostic criteria for stercoral perforation of the colon, and to analyze the patient outcome in a university hospital gastrointestinal surgery unit. METHODS: From November 1993 until November 1998 all surgically treated patients with a colorectal disease were prospectively recorded in a computerized database. Diagnosis of stercoral perforation of the colon was made if 1) the colonic perforation was round or ovoid, exceeded 1 cm in diameter, and lay antimesenteric; 2) fecalomas were present within the colon, protruding through the perforation site or lying within the abdominal cavity; and 3) pressure necrosis or ulcer and chronic inflammatory reaction around the perforation site were present microscopically. Any additional colon pathology led to exclusion from the diagnosis of stercoral perforation of the colon. Using the same criteria, 81 cases in the literature were found to qualify and were further analyzed. RESULTS: In a five-year period 1,295 patients underwent colorectal interventions through laparotomy. A total of 566 (44 percent) cases were emergencies, 220 (17 percent) of these caused by colonic perforation. Seven patients had stercoral perforation of the colon. The incidence of stercoral perforation of the colon was 0.5 percent of all surgical colorectal procedures through laparotomy, 1.2 percent of all emergency colorectal procedures, and 3.2 percent of all colonic perforations. The mean age of the patients was 59 (median, 64; range, 22–85) years. All perforations were situated in the left hemicolon or upper rectum. The round or ovoid perforation had a mean diameter of 3.6 cm. Fecalomas were present in all patients and protruded from the perforation site or were found within the free abdominal cavity in three of them. Generalized stercoral peritonitis was a constant finding. Using a colonic resection without immediate restoration of continuity, an extensive intraoperative lavage, and antibiotics, there was no in-hospital mortality. Analysis of the reports in the literature revealed additionally that 28 percent of patients with stercoral perforation of the colon have multiple stercoral ulcers in the colon and that substantial mortality is encountered if only minor surgical procedures of treatment are used. CONCLUSIONS: The incidence of stercoral perforation of the colon seemed to have been underestimated. The reason for this might be the lack of defined diagnostic criteria for this disease. Low mortality is obtained by early surgical eradication of the affected part of the colon, including all stercoral ulcers, and by aggressive therapy for peritonitis.Presented in part at the meeting of the Swiss Society of Surgery, Lugano, Switzerland, June 9 to 12, 1999.  相似文献   
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We report a case, which we believe to be rare, of adenosine-sensitive atrial tachycardia (AT) originating from the mitral valve annulus. The patient, a 73-year-old woman, died of unrelated cause 4 years after radiofrequency (RF) ablation therapy. Histologically, fibrous replacement of atrial musculature by mature collagenous tissue produced by the RF current was observed at the left inferior atrioventricular junction. In serial sections that included the coronary sinus, two distinct nodal structures containing small, pale myocytes within the fibrous tissue matrix were identified around the region of the ablation lesion. Our case appears to be a unique representation of tissue that was associated with the occurrence and maintenance of AT.  相似文献   
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Estrogenic chemicals are able to alter mammary gland development in female rodents, but little is known on the effects of anti-androgens and mixtures of endocrine disrupting chemicals (EDCs) with dissimilar modes of action.Pregnant rat dams were exposed during gestation and lactation to mixtures of environmentally relevant EDCs with estrogenic, anti-androgenic or dissimilar modes of action (TotalMix) of 100-, 200- or 450-fold high end human intake estimates. Mammary glands of prepubertal and adult female and male offspring were examined.Oestrogens increased mammary outgrowth in prepubertal females and the mRNA level of matrix metalloproteinase-3, which may be a potential biomarker for increased outgrowth. Mixtures of EDCs gave rise to ductal hyperplasia in adult males. Adult female mammary glands of the TotalMix group showed morphological changes possibly reflecting increased prolactin levels. In conclusion both estrogenic and anti-androgenic chemicals given during foetal life and lactation affected mammary glands in the offspring.  相似文献   
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Objective To quantify the 100 most frequently cited papers in CPT for predicting research hotspots for benefitting future clinical outcomes. Methods Web of Science database was searched for publications related to CPT original research from January 1, 1900 to December 31, 2022. And Cited Reference Search tool was employed for retrieving articles to determine the most cited item. Then a knowledge map was generated for number ofcitations, publication year, publication periodical, author unit, publication country and key words. Results Top 100 selected articles were cited from 11 to 196 times and publication period started from 1928 to 2016. Clinical research was the major type (n =93) and only 7 studies belonged to basic research. The largest contribution came from the United States (n =37), followed by Republic of Korea (n =9), Germany (n =6) and Italy (n=6). The frequently appearing keywords were divided into 2 groups of “Neurofibroma” and “Clinical characteristic of pseudarthrosis”. And term “NF1” was the latest hot spot in the most cited article. Conclusion Current researches on CPT focuse upon clinical treatment. Basic research on the pathogenesis of CPT is still relatively lacking. In the future, investment in basic research on CPT should be strengthened to provide a more comprehensive treatment for CPT. © 2022, Journal of Clinical Pediatric Surgery. All rights reserved.  相似文献   
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目的通过观察不同碘摄入水平的哺乳期母鼠及其仔鼠的碘代谢、甲状腺功能和形态的变化,探讨高碘摄入的亲代对其子代大鼠的保护作用。方法选用Wistar大鼠给予不同剂量的碘酸钾,喂养3个月后交配,观察母鼠乳汁碘及其与生后14日龄仔鼠的尿碘、甲状腺激素、甲状腺组织学变化等指标。结果(1)低碘组母鼠和仔鼠尿碘、血清T4水平均明显降低;母鼠甲状腺显著肿大,仔鼠甲状腺肿大虽不明显,但有明显的滤泡增生。(2)各高碘组母鼠尿碘水平随碘摄入量的增加而增加,二者呈平行关系,而乳汁含碘量仅表现为轻度升高,与碘摄入量不呈平行关系;各高碘组仔鼠的尿碘水平与母鼠乳汁含碘量呈平行关系。(3)各高碘组母鼠的血清T4随碘摄入量增加而降低,但未见甲状腺肿大,组织学表现为胶质蓄积性大滤泡增多和小滤泡增生同时存在,在50倍和100倍高碘组滤泡增生更明显;各高碘组仔鼠血清T4随碘摄入量的增加变化不明显,未出现母鼠发生的甲状腺功能减退(甲减)现象,甲状腺仅在100倍高碘组表现出轻度的滤泡增生。结论无论亲代和子代大鼠摄入的过量碘大部分从尿中排出;高碘摄入的亲代可能通过乳腺的调节作用减少了哺乳期子代对碘的摄入量;长期摄入过量碘的母鼠发生了甲状腺功能低下,但哺乳期仔鼠甲状腺功能基本正常;结果提示高碘摄入的亲代对其子代具有一定的保护作用。  相似文献   
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