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991.
Background: A growing number of reports describe markers with high frequencies of the ancestral alleles in Africa, contrasting with high frequencies and possibly fixation of derived variants out of Africa. Such a pattern can be explained by either neutral or non-neutral processes.

Aim: The study examined worldwide frequencies of two non-synonymous variants in NAD+-dependent succinic semialdehyde dehydrogenase (SSADH), in a search for possible signatures of natural selection favouring the derived alleles.

Subjects and methods: The typing of 1574 subjects were compiled, representing 60 populations from all continents. SSADH haplotype frequencies were correlated across 52 populations to those of 260 single nucleotide polymorphism (SNP) markers deposited in the CEPH database and of markers reported to be under positive Darwinian selection.

Results: In the world population, the c.538C variant is proceeding to replace the ancestral c.538T, shared with primates. The overall population differentiation is within the normal range. A significant correlation was also found between the frequencies of the derived alleles in SSADH and Microcephalin (MCPH1), which showed concerted changes worldwide and, at least in Asian populations, also on a restricted geographical scale.

Conclusion: The analysis of robust correlations based on a large panel of populations is potentially able to identify clusters of genomic regions or genes showing co-evolution of the frequencies of derived alleles.  相似文献   
992.
993.
994.
Background.?The prevalence of the metabolic syndrome increases with age and after the onset of menopause, and may explain in part the apparent acceleration of cardiovascular disease in postmenopausal women.

Objective.?To determine the prevalence of metabolic syndrome and related risk determinants among postmenopausal women in Ecuador.

Methods.?Postmenopausal women ≥40 years of age, non-users of hormone therapy and with an intact uterus, were asked to participate in a metabolic syndrome screening and educational program at the Institute of Biomedicine of the Universidad Católica of Guayaquil, Ecuador. Sociodemographic data, waist circumference and blood pressure measurements were recorded, and a fasting blood sample obtained for serum glucose and lipid profile determinations. Woman were counseled and managed according to the results. Metabolic syndrome was defined in accordance with the criteria of the Third Adult Treatment Panel (ATP III).

Results.?Three hundred and twenty-five postmenopausal women entered the program. Mean (±standard deviation) age was 55.9 ± 8.1 years, 53.5% of them were aged ≥54 years (median). The prevalence of metabolic syndrome, according to ATP III criteria, was 41.5%. Using the same criteria, 38.8%, 16.6%, 56.9% and 54.2% of the women presented with hypertension, diabetes, hypertriglyceridemia and abdominal obesity, respectively. More than 40% of women determined to have hypertension or diabetes lacked knowing so. Logistic regression analysis determined that age increased the risk of presenting hypertension and diabetes (odds ratio (95% confidence interval): 2.0 (1.2–3.2) and 1.6 (0.9–3.0), respectively, p < 0.05), entities which in turn duplicated the risk of having high triglyceride levels. Sedentary women with <5 years since menopause onset were at higher risk of having abdominal obesity, which was directly related to diabetes and hypertension.

Conclusions.?In this postmenopausal Ecuadorian population the prevalence of the metabolic syndrome was high and its determinant factors related to age, time since menopause onset and sedentary habits. Because of the implications for cardiovascular risk, counseling programs directed toward high-risk populations should be encouraged.  相似文献   
995.
Background: The recovery of foetal remains is very sporadic in archaeology, especially due the scarce degree of bone mineralisation. This paper presents the singular archaeological discovery of a foetal tile preserving the bone remains, object of our anthropological examination.

Materials and methods: The foetal tile was discovered during an archaeological excavation in a medieval site (Northern Italy). The tile was analysed by CT scan and later, human remains were anthropologically examined.

Results: The archaeological investigation revealed a special ritual destined to foetuses while forensic anthropological analysis allowed estimating the gestational age near to 21–24?weeks.  相似文献   
996.
997.
The prevalence of menometrorrhagia in fertile women is 11.4–13.2% and increases with aging. The presence of metrorrhagia is a relatively common cause of concern among adolescents and their parents, as well as a frequent cause of visits to emergency departments, gynaecologists, and pediatricians. Clomiphene is a selective estrogen receptor modulator (SERM) that increases the production of gonadotropins by inhibiting negative feedback on the hypothalamus.

Clomiphene is primarily used in the treatment of female infertility for ovulation induction to reverse oligoovulation or anovulation, as occurs in polycystic ovary syndrome.

Objective: The aim of our study was to evaluate the use of clomiphene citrate in ovulation induction, and therefore, in the cessation of bleeding in adolescents with menometrorrhagia in the absence of uterine, ovarian, or systemic pathologies.

Design: Cohort study.

Materials and methods: The study group was comprised of 50 subjects (age range, 13–16 years) with menometrorrhagia (bleeding >7 days in length with an average blood loss >80?ml). The treatment with clomiphene citrate at a dose of 50?mg/day for 5 days during the attack cycle, and from days 3 to 7 of three subsequent cycles, was offered to the patients.

Results: After three cycles of therapy, all patients had resolution of the menometrorrhagia and resumption of ovulatory cycles. No patient reported unwanted side effects.

Conclusion: We propose that low-dose clomiphene should be the first step in the treatment of adolescent dysfunctional bleeding (DUB).  相似文献   
998.
Neonatal uterine bleeding (NUB) has been carefully studied in the past through case reports, small series, clinical cohort studies, pathology investigations of fetal and neonatal. Following a historical recount, this review summarizes biological mechanisms conditioning NUB, starting from the persistence till birth of an 'ontogenetic progesterone resistance' (OPR), causing decreased responsiveness of target tissues to bioavailable progesterone. Several pregnancy-related conditions, such as preeclampsia, fetal growth restriction, prematurity, post-maturity and even Rhesus or ABO incompatibility, influence the occurrence of NUB. It seems therefore that the phenomenon is precipitated by chronic fetal distress. When present, OPR may persists until telarche; as a consequence, if pregnancy occurs in early teenage, the disorder known as “defective deep placentation” may ensue, increasing the risk of obstetrical syndromes. In the presence of NUB, retrograde shedding into the peritoneal cavity of endometrial stem/progenitor and niche cells may occur. There, given the right environment, these cells can survive and become activated at the time of telarche, causing the specific phenotype of early-onset endometriosis. In conclusion, neonatal menstruation is a fetal distress indicator and can alter the incidence of a variety of pathological conditions later in life. For this reason, it should be carefully recorded and the parents informed.  相似文献   
999.
1000.
Quality of life in women with recurrent breast cancer   总被引:6,自引:0,他引:6  
Although the psychosocial concomitants of early-stage breast cancer have been well-documented, the relationship between cancer recurrence and quality of life remains less clear. We conducted a prospective, longitudinal study in order to clarify the relationship between recurrent cancer and quality of life, and to determine predictors of quality of life following recurrence. Sixty-nine women with recurrent breast cancer completed questionnaires assessing multiple components of quality of life at three time points: prior to recurrence, immediately after the diagnosis of recurrence, and at follow-up 6 months later. Perceptions of overall quality of life, general health status, emotional, social, and physical functioning were poorer immediately following the diagnosis of recurrence than they had been prior to recurrence. These women also evidenced significant improvement in several domains of quality of life between initial recurrence and follow-up; nonetheless, most areas of quality of life were impaired compared to pre-recurrence. Self-reported physical symptoms were a strong predictor of post-recurrence ratings of overall quality of life. These data suggest that the recurrence of breast cancer is associated with significant changes in quality of life. Quality of life did not progressively deteriorate, however, attesting to the resilience of women coping with this major stressor. These data shed light on issues of potential importance to patients managing this serious illness and may have implications for health-care professionals working with this population.  相似文献   
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