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991.
992.

Objective

To assess trends in twinning over four decades using a population-based registry.

Design

Ecological study to conduct trend analysis of twin pregnancies in a geographically defined area over 40 years.

Setting

All pregnancies in the Cardiff and Vale of Glamorgan area of South Wales from 1965 to 2004, as recorded in the Cardiff Birth Survey (CBS) database.

Methods

Trends of the incidence of all twin pregnancies (≥18 weeks of gestation) were calculated in 5-year increments, beginning with 1965–1969 and ending in 2000–2004. Natural twinning rates could only be calculated for the terminal five time periods (i.e., 1980–1984, 1985–1989, 1990–1994, 1995–1999, and 2000–2004), when information regarding non-spontaneous (iatrogenic) twinning was first collected in the database. All results were adjusted for maternal age.

Results

The total twinning rate was 13.1 per 1000 pregnancies in the 1st time period (1965–1969). Subsequently, there was a gradual reduction in twinning, reaching a nadir of 10.3 per 1000 for the time period 1980–1985 (Z = 3.15, P value < 0.001). This was followed by a gradual increase in twinning, reaching a maximum of 15.7 per 1000 for both 1995–1999 and 2000–2004 (Z = −5.18, P value < 0.0001). After exclusion of the cases of iatrogenic pregnancies, the natural twinning rate showed a continuous and gradual increase from 10 per 1000 spontaneous pregnancies in 1980–1984 to 13.3 per 1000 in 2000–2004 (Z = −5.08, P value < 0.0001).

Conclusion

The data showed a gradual, continuous increase in natural twinning rates over the last two decades. Such an increase cannot be attributed to the rise in maternal age alone.  相似文献   
993.
An immense body of literature on the effects of hypertension on perinatal morbidity and mortality exists, but only a handful of studies have reported adverse outcomes associated with low maternal blood pressure during pregnancy. This study aimed to investigate if there is an increased risk of fetal loss associated with hypotension during pregnancy. A matched case-control study of stillbirth and maternal blood pressure was conducted in which maternal blood pressures for a total of 124 pregnancies culminating in stillbirth were compared with maternal blood pressures in 243 (matched) pregnancies resulting in a liveborn infant. Women whose diastolic blood pressures fell in a borderline range (60 to 70 mm Hg) were consistently at greater risk of stillbirth relative to normotensive pregnancies. Women who had three or more mean arterial pressure values < or = 83 mm Hg during the course of their pregnancy were at nearly twice the risk of stillbirth (odds ratio 1.78; 95% confidence interval [CI] 1.06 to 2.99; P = 0.03). Systolic hypotension was not significantly associated with stillbirth, but proportionately more control women were noted to have systolic hypertension (SBP > or = 130 mmHg) than cases, and the adjusted odds of stillbirth in women who were hypertensive at either their first or last antenatal visit or whose antenatal average SBP was > or = 130 mm Hg were all very close to 0.4 (95% CI 0.37 to 0.43; P = 0.02 to 0.03) relative to normotensives. We concluded that maternal hypotension, particularly borderline hypotension, may be a contributory risk factor for stillbirth. Women with hypertension in pregnancy may now be at a decreased risk of stillbirth as a result of the close care and treatment they receive.  相似文献   
994.
Crew resource management (CRM), adapted from aviation for the practice of medicine, offers the potential of reducing medical errors, increasing employee retention, and improving patient satisfaction. CRM, however, requires a culture that promotes teamwork and acceptance of new concepts. Leadership is needed to transform the culture, as well as to train, coach, and sustain the behavior CRM demands. Culture change can be fostered through teamwork activities that, when made part of a daily routine, provides the basis for modeling teamwork skills and sets the stage for sustained culture change. New tools are available to measure processes as well as patient and staff satisfaction.  相似文献   
995.
996.
PURPOSE OF REVIEW: Human epidemiological and animal studies show that many chronic adult conditions have their antecedents in compromised fetal and early postnatal development. Developmental programming is defined as the response by the developing mammalian organism to a specific challenge during a critical time window that alters the trajectory of development with resulting persistent effects on phenotype. Mammals pass more biological milestones before birth than any other time in their lives. Each individual's phenotype is influenced by the developmental environment as much as their genes. A better understanding is required of gene-environment interactions leading to adult disease. RECENT FINDINGS: During development, there are critical periods of vulnerability to suboptimal conditions when programming may permanently modify disease susceptibility. Programming involves structural changes in important organs; altered cell number, imbalance in distribution of different cell types within the organ, and altered blood supply or receptor numbers. Compensatory efforts by the fetus may carry a price. Effects of programming may pass across generations by mechanisms that do not necessarily involve structural gene changes. Programming often has different effects in males and females. SUMMARY: Developmental programming shows that epigenetic factors play major roles in development of phenotype and predisposition to disease in later life.  相似文献   
997.
998.
In an attempt to better understand the relationship between male use of the sex industry (i.e., pornography and strip clubs) and interpersonal violence (IPV), 2,135 female residents of an IPV shelter were surveyed regarding their batterer's use of both the sex industry and controlling behaviors in their relationship. Findings indicate that male domestic violence offenders who utilize the sex industry use more controlling behaviors than male domestic violence offenders who do not. Implications for policy, practice, and research are discussed.  相似文献   
999.
Colo-uterine fistula of diverticular origin is an extremely rare disease due to the resistance of uterine tissue. Methods for diagnosis remain to be established. Non-invasive imaging like magnetic resonance imaging (MRI) may help to establish a proper diagnosis, but confirmation may be reached by diagnostic hysteroscopy or even surgical exploration. We report a 78-year-old female who presented with continuous dull aching pain associated with increasing constipation. MRI suspected a fistula between the posterior aspect of the uterine body and the sigmoid colon which contained extensive diverticulosis. Hysteroscopy confirmed the fistulous opening, but colonoscopy confirmed diverticular disease with no evidence of malignancy. The patient had en block surgical treatment of the uterus and the adjacent colon, followed by an uneventful recovery. The sensitivity and specificity of non-invasive imaging procedures to diagnose such cases remain to be established. As imaging procedures cannot rule out neoplasia, endoscopic procedures need to be added.  相似文献   
1000.
Endometrial carcinoma is the most common malignancy of the female genital tract in industrialized countries, and occurs predominantly after the menopause. Although most endometrial carcinomas are detected at low stage, there is still a significant mortality from the disease. In postmenopausal women, prolonged life expectancy, changes in reproductive behavior and prevalence of overweight and obesity, as well as hormone replacement therapy use, may partially account for the observed increases of incidence rates in some countries. In order to improve treatment and follow-up of endometrial carcinoma patients, the importance of various prognostic factors has been extensively studied. The identification of high-risk groups would make it possible to avoid unnecessary adjuvant treatment among patients with a good prognosis. Over the past few decades, several studies have demonstrated the prognostic importance of different parameters including lymph node status, histological type of carcinoma (serous carcinoma and clear cell carcinomas are poor prognostic types), histological grade, stage of disease, depth of myometrial invasion, lymphovascular space involvement and cervical involvement. Other factors currently being investigated are estrogen and progesterone receptor status, p53 status, flow cytometric analysis for ploidy and S-phase fraction, and oncogenes such as HER-2/neu (c-erbB-2).  相似文献   
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