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101.

Purpose

Previous research assessing the impact of pregnancy and age at first pregnancy on breast cancer risk in BRCA1 and BRCA2 mutation carriers has produced conflicting results, with some studies showing an increased risk following early first pregnancy in contrast to the reduced risk in the general population of women. The present study addresses these inconsistencies.

Methods

Female BRCA1 and BRCA2 carriers from North West England were assessed for breast cancer incidence prior to 50 years of age comparing those with an early first full-term pregnancy (< 21 years) to those without a full-term pregnancy. Breast cancer incidence per decade from 20 years and Kaplan–Meier analyses were performed.

Results

2424 female mutation carriers (1278 BRCA1; 1146 BRCA2) developed 990 breast cancers under the age of 50 years. Women who had their first term pregnancy prior to age 21 (n = 441) had a lower cancer incidence especially between age 30–39 years. Kaplan–Meier analysis showed an odds ratio of 0.78 for BRCA1 (p = 0.005) and 0.73 for BRCA2 (p = 0.002).

Conclusions

The present study demonstrates a clear protective effect of early first pregnancy on breast cancer risk in both BRCA1 and BRCA2 mutation carriers.
  相似文献   
102.
For a seven year period (1985-91) clinical and epidemiological data were prospectively collected on children aged < 10 years with microbiologically confirmed invasive Haemophilus influenzae type b infection in the Oxford region to study the epidemiology of the disease and determine the potential impact of early primary immunisation in infants. Computer records of primary immunisations given to these cases were retrospectively analysed and, where necessary, hospital and general practitioner records were searched to determine the immunisation history. Over the seven year period, 416 cases of invasive H influenzae type b disease were reported. Widescale immunisation against H influenzae type b began in 1991 as part of a regional trial. The estimated annual incidence for invasive disease between 1985 and 1990 was 35.5 cases per 100,000 children aged less than 5 years; for H influenzae type b meningitis it was 25.1 per 100,000 children aged less than 5 years. The cumulative risks for invasive disease and meningitis by the fifth birthday were one in 560 and one in 800 respectively. The majority of disease (71%) occurred in children less than 2 years of age with the peak monthly incidences at 6 and 7 months of age. The overall mortality was 4.3% and 50% of these deaths occurred suddenly. Most (91%) of the children had received at least one primary immunisation against diphtheria, tetanus, and pertussis before H influenzae type b infection and there was only one case of parental refusal of immunisation. None had received H influenzae type b immunisation. Given a vaccine uptake of 90% by 5 months of age it is estimated that at least 82% of the H influenzae type b infections could have been prevented. Extrapolated nationally, 1150 cases of infection and 50 deaths could be prevented each year by routine primary immunisation.  相似文献   
103.
Bilateral peripheral pulmonary infiltrates caused by Pneumocystis carinii developed in a patient undergoing mediastinal irradiation after chemotherapy for Hodgkin disease. The paramediastinal part of the lung included within the treatment port remained clear during the 2 1/2 weeks of radiation therapy. The distribution of the pneumocystis infiltrates was altered by the radiation, producing a pattern that is the "radiographic negative" of typical post-radiation therapy paramediastinal fibrosis.  相似文献   
104.
目的 评价B超引导穿刺的微通道( F12F16)经皮肾镜碎石术治疗肾盏结石的安全性和有效性.方法 2009年5月2011年8月共收治ESWL无效及透X线肾盏结石44例(44侧肾结石),其中下盏结石24侧,中盏结石11侧,分支性肾盂上盏合并下盏结石9侧,结石长径(16.14±5.12)mm.采用B超引导穿刺的微通道(F12~F16)经皮肾镜碎石术,气压弹道击碎并清除结石.结果 44例均一期建立通道并碎石,其中单通道36侧肾,双通道9侧肾;经上盏建立通道9个,经中盏11个,经下盏33个.手术时间(49.3±10.9)min,一期手术结石清除率97.73% (43/44).术后血红蛋白含量较术前下降(9.13±3.7)g/L.围手术期无输血,与手术相关的感染发生率为6.18% (3/44),主要表现为术后发热,无气胸或腹腔脏器损伤.44例随访6~20个月,平均11.4个月,1例残余结石排出,术后6个月结石复发率为2.27%(1/44),1年结石复发率为6.18% (3/44).结论 B超引导穿刺的微通道经皮肾镜碎石术治疗肾盏结石有效、安全,是此类结石的首选治疗方法.  相似文献   
105.
The adoption of digital signal processing (DSP) microchips for detection and analysis of electrocardiographic signals offers a means for increased computational speed and the opportunity for design of customized architecture to address real-time requirements. A system using the Motorola 56001 DSP chip has been designed to realize cycle-by-cycle detection (triggering) and waveform analysis using a time-domain template matching technique, correlation waveform analysis (CWA). The system digitally samples an electrocardiographic signal at 1000 Hz, incorporates an adaptive trigger for detection of cardiac events, and classifies each waveform as normal or abnormal. Ten paired sets of single-chamber bipolar intracardiac electrograms (1–500 Hz) were processed with each pair containing a sinus rhythm (SR) passage and a corresponding arrhythmia segment from the same patient. Four of ten paired sets contained intraatrial electrograms that exhibited retrograde atrial conduction during ventricular pacing; the remaining six paired sets of intraventricular electrograms consisted of either ventricular tachycardia (4) or paced ventricular rhythm (2). Of 2,978 depolarizations in the test set, the adaptive trigger failed to detect 6 (99.8% detection sensitivity) and had 11 false triggers (99.6% specificity). Using patient dependent thresholds for CWA to classify waveforms, the program correctly identified 1,175 of 1,197 (98.2% specificity) sinus rhythm depolarizations and 1,771 of 1.781 (99.4% sensitivity) abnormal depolarizations. From the results, the algorithm appears to hold potential for applications such as realtime monitoring of electrophysiology studies or detection and classification of tachycardias in implantable antitachycardia devices.  相似文献   
106.
HLA配型与肾移植术后早期急性排斥反应的关系   总被引:3,自引:0,他引:3  
目的 研究HLA配型与尸体肾移植术后早期急性排斥反应的关系。方法 将262例尸体肾移植受者按HLA配型的误配率(MM)进行分组,统计各组术后1~2个月内急性排斥反应的发生次数。结果 当MM〉3时,若接受的器官HLA抗原/基因为可接受性,术后急性排斥反应的发生率为16.4%;若供体器官HLA抗原/基因具免疫原性,则急性排斥反应的发生率为33.1%,两者比较,P〈0.05。结论 供受者间HLA配型越好  相似文献   
107.
目的 观察成人胰岛细胞及肾联合移植治疗胰岛素依赖型糖尿病合并尿毒症的临床效果。方法 对 4例胰岛素依赖型糖尿病合并尿毒症的患者施行成人胰岛细胞及肾联合移植。肾移植为常规术式 ,在移植肾开放血液循环后 ,将分离、纯化、培养好的胰岛细胞注入门静脉中。移植后监测患者的空腹血糖、基础C 酞、糖化血红蛋白及肾功能的变化 ,并与其术前各项指标比较。结果  4例患者术后在观察期间内胰岛素的用量均较术前减少超过 2 5 % ,且持续 3个月以上 ;空腹血糖基本保持在正常水平 ,基础C 酞也基本维持在正常水平 ,糖化血红蛋白于术后降至正常水平 ;4例患者的移植肾功能良好 ,3例患者已恢复正常工作。结论 成人尸体胰岛细胞及肾联合移植治疗胰岛素依赖型糖尿病合并尿毒症的临床效果较好 ,具有操作简单、安全等优点  相似文献   
108.
Radiocontrast-induced nephropathy (RCIN) is a common cause of hospital-acquired acute renal failure and is associated with a high mortality rate. RCIN is potentially preventable, because administration of the radiocontrast agent is predictable, and a high-risk population has been identified. This multicenter, prospective, randomized, double-blind, placebo-controlled trial was performed to evaluate the efficacy of intravenous atrial natriuretic peptide (anaritide, ANP 4-28) to prevent RCIN. Patients with stable chronic renal failure (serum creatinine greater than 1.8 mg/dL or serum creatinine between 1.5 and 1.8 mg/dL with estimated creatinine clearance of < or = 65 mL/min) were assigned to receive either placebo or one of three doses of anaritide (0.01 microg/kg/min, 0.05 microg/kg/min, or 0.1 microg/kg/min) for 30 minutes before and continuing for 30 minutes after radiocontrast administration. All patients were given intravenous 0.45% saline for 12 hours before the radiocontrast procedure and continuing for 12 hours after the last dose of radiocontrast. Both ionic and nonionic radiocontrast agents were administered. RCIN was defined as either an absolute increase of serum creatinine of > or = 0.5 mg/dL or a percent increase of > or = 25% over baseline. Of the 247 patients who completed the study, 50% had diabetes mellitus. There were no statistical differences in baseline serum creatinine, change in serum creatinine, or the incidence of RCIN. The incidence of RCIN was placebo, 19%; anaritide (0.01), 23%; anaritide (0.05), 23%; anaritide (0.1), 25%. Patients with diabetes mellitus had a significantly greater incidence of RCIN: placebo, 26% versus 9%; anaritide (0.01), 33% versus 13%; anaritide (0.05), 26% versus 21%; anaritide (0.1), 39% versus 8% (diabetic v nondiabetic, P < 0.002). There was no effect in the diabetic or nondiabetic groups by anaritide on the incidence of RCIN. Comparison of the highest-risk group of patients, defined as patients with diabetes mellitus and a baseline serum creatinine > or = 1.8 mg/dL, with the lowest-risk group, defined as patients without diabetes mellitus and a baseline serum creatinine of 1.8 mg/dL or less, did not show a beneficial effect of anaritide administration. In conclusion, administration of intravenous anaritide before and during a radiocontrast study did not reduce the incidence of RCIN in patients with preexisting chronic renal failure, with or without diabetes mellitus.  相似文献   
109.
110.
目的 探讨IgA肾病的病理特点,提高诊断合格率.方法 回顾性分析3例有血尿症状的IgA肾病患者被误诊为尿路感染血尿的经过和原因.结果 3例患者均为系膜增生性IgA肾病患者,HaasⅠ级2例、HaasⅡ级1例,均于发病前出现过尿路感染,确诊后均已治愈.结论 IgA肾病的复杂性和隐匿性使其易被误诊,临床诊断要全面掌握IgA肾病的临床与病理特点,不能局限于表面症状的诊断.  相似文献   
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