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The prevalence and heterogeneity of Chlamydia trachomatis infections in a cohort of female sex workers in Dakar (Senegal) were determined by using endocervical-swab-based PCR DNA amplification assays. The overall prevalence of cervical chlamydial infection was 28.5% (206 of 722), and most of these infections were asymptomatic. An increased number of sexual partners was significantly associated with infection (adjusted odds ratio [AOR] = 1.37; 95% confidence interval [CI] = 1.06 to 1.77), while the presence of a yeast infection was negatively associated with chlamydial infection (AOR = 0.28; 95% CI = 0.10 to 0.83). Six different C. trachomatis genotypes were identified based on phylogenetic analysis of the omp1 gene sequences. Interestingly, genotype E predominated (47.6%) and was not associated with visible signs of cervical inflammation compared to non-E genotypes (P < 0.05). Overall, the high rate of asymptomatic C. trachomatis infection by genotype E may suggest genotype-specific properties that confer a transmission advantage in this high risk population.  相似文献   
617.
The melting behaviour of semicrystalline poly(3,3-diethylthiethane) (PDET), was studied by differential scanning calorimetry (DSC), wide-angle X-ray scattering (WAXS), small-angle light scattering (SALS), and thermooptical analysis (TOA). Two samples of number-average molecular weights 6,0 · 104 and 1,8 · 105 and rather narrow molecular weight distributions (ratio of weight-to number-average molecular weights M?w/M?n = 1,3) were analyzed. When PDET is isothermally crystallized from the molten state in the range 275–333 K, the calorimetric curves show one or two melting endotherms, depending on crystallization temperature (Tc) and heating rate. WAXS analysis shows conclusively that polymorphism is absent. It was shown that the melting behaviour of PDET is being dictated by processes of melting and recrystallization occurring during the experimental analysis.  相似文献   
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The goal of our study is to assess the anatomical type of the superficial temporal artery (STA) in the black population using the classification of Ricbourg et al.. Forty-seven fresh cadavers and three extracted and frozen heads were included in this study. The external carotid artery was isolated in the neck and injected by Rhodopas stained with Congo Red. The superficial temporal artery was dissected using a Y-shaped skin incision. The last step of the procedure was to remove the flap of the fascia superficialis temporis. The third segment of the superficial temporal artery and its terminal branches were studied. This segment courses cephalad and wraps the zygomatic arcade. It splits into two terminal branches: the temporo-frontal and the temporo-parietal ones. The most important of its collaterals, the zygomato-maleus artery, plays a crucial role for distinguishing the subtypes of STA according to the classification of Ricbourg et al.. Indeed, this branch can be subdivided into two types: --type I: the zygomato-malar artery arises from the trunk of the STA; it courses perpendicular and with a slightly ascending direction; this type accounts for 93% of the cases. --type II: the zygomato-malar artery originates from the branch of the temporo-frontal artery. Its course is either horizontal or caudad. This type accounts for 3% of the cases. Our results confirm those of Ricbourg et al.. Thus, we could not CONFIRM the notion of a racial predominance of typology of the STA in our context. We did not study the dimensions of STA and also the level of its bifurcation. Indeed, it has been largely reported in the literature. These elements constitute the anatomic basis of the surgical use of temporal flaps. The vessel-containing tissue in which travels the STA forms the so-called fascia temporalis superficialis whose plasticity and polyvalency are critical during the procedures of plastic and reconstructive surgeries.  相似文献   
619.
Still frequent in Africa, the idiopathic peripartum cardiomyopathy (PPC) is the subject of only few prospective studies. The aim of this prospective work was to assess the echocardiographic abnormalities of the PPC and to determine on 26 patients the evolution and the prognostic factors of this disease. Six women had mild to moderate pericardial effusion. The abnormalities of the wall motion, constantly found, were diffuse in 20 cases (77.1%) and localized or prevalent on the interventricular septum or the left ventricular posterior wall in the other cases. The cardiac chambers were dilated in 24 cases (92.3%). Left ventricular hypertrophy was noted among 16 patients (61.5%); it was eccentric in 15 cases. The left ventricular systolic dysfunction was constant. The other abnormalities were: the abnormal left ventricular relaxation (one case), low mitral and aortic flow (12 cases), the mitral (21 cases) and tricuspid regurgitation (five cases). One noted a septal hypertrophy and an isolated dilatation of the right ventricle. The mean follow-up was 7.3 +/- 1 month (1-18 months). Two patients died at the 4th and 8th month. Among the 24 survivors, 11 had normalized were: the gestity (p = 0.01), the parity (p = 0.01), the cardiothoracic ratio (p = 0.04), the left ventricular volumes (p = 0.02), and the parameters of left ventricular function. The echocardiography of patients with PPC usually shows a pattern of dilated and hypokinetic cardiomyopathy, but many variations are possible. Most of the patients keep echocardiographic abnormalities after mean term follow-up.  相似文献   
620.
RDD (Rosai Dorfman disease) is a rare and benign histiocytic proliferative disorder of unknown etiology. FNAC (Fine‐needle aspiration cytology) is a useful and reliable tool for the diagnosis of RDD, and as such, biopsy is avoidable.  相似文献   
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