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Postpartum months provide a challenging period for poor women. This study examined patterns of menstrual resumption, sexual behaviors and contraceptive use among urban poor postpartum women. Women were eligible for this study if they had a birth after the period September 2006 and were residents of two Nairobi slums of Korogocho and Viwandani. The two communities are under continuous demographic surveillance. A monthly calendar type questionnaire was administered retrospectively to cover the period since birth to the interview date and data on sexual behavior, menstrual resumption, breastfeeding patterns, and contraception were collected. The results show that sexual resumption occurs earlier than menses and postpartum contraceptive use. Out of all postpartum months where women were exposed to the risk of another pregnancy, about 28% were months where no contraceptive method was used. Menstrual resumption acts as a trigger for initiating contraceptive use with a peak of contraceptive initiation occurring shortly after the first month when menses are reported. There was no variation in contraceptive method choice between women who initiate use before and after menstrual resumption. Overall, poor postpartum women in marginalized areas such as slums experience an appreciable risk of unintended pregnancy. Postnatal visits and other subsequent health system contacts provide opportunities for reaching postpartum women with a need for family planning services.  相似文献   
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Ultrasound treatment has been proposed by several authors to enhance the repair of long bone injury. The present study investigated in a murine model the treatment by low-intensity pulsed ultrasound (LIPUS) of calvarial flat bone defect. The animals were operated to create bone defect and exposed to ultrasound for 5 min per day, 5 d per week, during two weeks. Two intensities of ultrasound (1 MHz, 100 Hz pulse repetition frequency and 20% duty cycle) were investigated: 100 and 300 mW/cm2 spatial-averaged, time-averaged. Re-ossification surface and volume were determined after 30 and 60 days using computerized X-ray tomography in all animals of the control and treated groups. The results showed a significant increase of bone re-ossification in the group treated with the higher-intensity ultrasound (mean value of 18% volume reconstruction), whereas lower bone reconstruction was observed in the lower-intensity and control groups (respective mean values of 10 and 12% volume reconstruction). (E-mail: bernard.lavandier@inserm.fr)  相似文献   
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BACKGROUND: Cellular angiofibroma (CA) of the vulva is a recently described condition, whose clinical and pathological features are poorly known. METHODS: We have encountered two cases of this very unusual tumor. Their clinical and pathological features were analyzed and compared to those reported in the literature. RESULTS: Both patients were middle-aged women. In each case, the lesion had the clinical appearance of a vulvar cyst, located in the lateral aspect of the clitoris and the right labium majus, respectively. Microscopically, the lesions were well circumscribed but not truly encapsulated. Both were composed of small spindle cells arranged in short fascicles and mixed up with relatively abundant small- or medium-sized rounded vessels. While mitotic activity was perceptible in both cases, no cellular atypia could be demonstrated. A striking feature seen in one case was the presence of pseudoangiomatous changes in the stroma, similar to those occasionally found in spindle cell lipoma. Phenotypically, the tumor cells consistently expressed vimentin, CD99, and both estrogen and progesterone receptors. A discrete CD34 or smooth muscle actin immunoreactivity was also found in one case. No expression of S-100 protein, Bcl-2 protein, CD117 (c-kit gene product), epithelial membrane antigen, desmin, or h-caldesmon could be demonstrated. CONCLUSION: This study further illustrates that CA of the vulva has distinct clinical and pathologic features that set it apart from the other soft tissue conditions involving this area. However, like many soft tissue neoplasms, this tumor also exhibits some variation in its histological or immunohistochemical features.  相似文献   
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Purpose: The aim of this work was to study amniotic fluid [beta ]-endorphin as a potential predictor for postnatal morbidity in gastroschisis. Methods: Beta-endorphin was assayed in 43 amniotic fluid samples from 13 pregnant women with fetal gastroschisis undergoing diagnostic amniocentesis or therapeutic amnioinfusion and compared with 33 controls. Within the gastroschisis group, the authors investigated the relationship between postnatal morbidity and the peak value of amniotic fluid [beta ]-endorphin (AFBE). Results: Ten AFBE values in 6 cases of gastroschisis were above the upper limit of the 95% confidence interval derived from controls. Postnatal morbidity was significantly higher when peak AFBE exceeded 10 [mu ]g/L (n = 4 pregnancies) compared with below 5 [mu ]g/L (n = 9 pregnancies), as shown by mean duration of mechanical ventilation (15.2 v 3 days; P = .01), of parenteral feeding (77 v. 18.7 days; P = .04), and of hospitalization (84 v 32.2 days; P = .04). There was no statistically significant association between postnatal morbidity markers and prenatal dilation of fetal bowel. Conclusions: The most severe cases of gastroschisis are associated with high levels of AFBE. The authors speculate that this fetal hormonal response could result from stress or pain caused by prenatal bowel damage.  相似文献   
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Hepatic vascular exclusion (HVE) combines portal triad clamping and occlusion of the inferior vena cava. Although HVE has been performed for major liver resections during the last 2 decades, little is known about the mechanisms that explain its satisfactory hemodynamic tolerance. Consequently, we performed a comprehensive study of both hemodynamic and hormone responses to HVE. Twenty-two patients who underwent liver resection for secondary tumors developed in noncirrhotic livers were prospectively studied. Heart rate, arterial blood pressure, pulmonary artery pressure, mixed venous saturation, cardiac output, and left ventricular dimensions determined by transesophageal echocardiography were monitored in HVE patients. Blood concentrations of arginine vasopressin (AVP), epinephrine, norepinephrine, dopamine, and atrial natriuretic peptide and plasma renin activity (PRA) were measured before clamping; 5, 15, and 30 min after clamping; and 15 min after unclamping. Hemodynamic response to HVE was characterized by a significant (P < 0.05) decrease in left ventricular dimensions, fractional area change, and pulmonary artery pressure. We also observed a marked decrease in cardiac output (50%) and an increase in heart rate and systemic vascular resistance. After unclamping, there was peripheral vasodilation, assessed by a significant decrease in systemic vascular resistance from the preclamping value to unclamping. An acute and sustained increase in AVP and norepinephrine that returned to baseline after unclamping and the absence of modification in PRA concentrations were noted. The marked decrease in venous return that characterizes HVE is compensated for by an increase in vascular resistance secondary to an important activation of the AVP and sympathetic systems. The PRA system does not play an important role in maintaining arterial blood pressure during HVE. IMPLICATIONS: Hemodynamic and hormonal responses to the acute interruption of caval venous return to the heart were investigated in patients undergoing liver resection with hepatic vascular exclusion. A compensatory role for arginine vasopressin and sympathetic systems that provoked increased vascular resistance was demonstrated.  相似文献   
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