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1.
To study the spread of sexually transmitted diseases (STDs) using social/sexual mixing models, one must have quantitative information about sexual mixing. An unavoidable complication in gathering such information by survey is that members of the surveyed population will almost certainly have sexual contacts outside that population. The number of these outsiders may be substantial and, hence, important for the modelling process. In this paper, we develop a mark-recapture model for estimating the size of the population at risk for contracting a STD due to direct sexual contact with a specified population targeted by a survey. This mark-recapture methodology provides a reliable method of estimating the number of outsiders. Because not everyone in the targeted population may be sexually active, the size of the sexually active subset, used as the number marked in our tag-recapture formulation, must be estimated, which introduces extra variability. We derive an estimator of the variance of the estimated total number at risk that accounts for this extra variability and an expression for the bias of that estimator. We extend the methodology to stratified surveys and illustrate its use with data collected from a population of university undergraduates to estimate sexual mixing parameters of a deterministic model of the spread of STDs. 相似文献
2.
J C Shih T L Ko M C Lin M K Shyu C N Lee F J Hsieh 《Ultrasound in obstetrics & gynecology》2004,24(2):202-206
The relationship of large and vascularized chorioangiomas to adverse pregnancy outcome is well recognized. We present a patient with a large placental tumor and signs of impending fetal cardiac failure. The angioarchitecture of the tumor depicted by three-dimensional (3D) power Doppler ultrasound enabled us to accurately diagnose a placental chorioangioma. During the follow-up period, quantitative flow data obtained using 3D power Doppler indicated altered hemodynamics in the tumor and concomitant improvement in the condition of the fetus, enabling us to manage the mother conservatively. Spontaneous delivery occurred at 38 weeks without any complications. This report demonstrates the potential value of 3D power Doppler in prenatal diagnosis and monitoring of pregnancies complicated by large, vascularized chorioangioma. 相似文献
3.
RY Anadolu † A Birol ‡ S Bostanci † A Boyvat† 《Journal of the European Academy of Dermatology and Venereology》2002,16(2):152-153
Pemphigus vulgaris is an autoimmune blistering disorder in which both genetic and environmental factors, mainly drugs, are thought to play a part in its aetiopathogenesis. Although some drugs that contain thiol groups, such as D-penicillamine and captopril, and non-thiol drugs, such as cephalosporin, have been reported to trigger or induce pemphigus, there are no previous reports regarding the influence of quinolones in triggering this disease. Here we present a case of pemphigus possibly triggered by quinolones. 相似文献
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J C Shih S S Peng S M Hsiao J H Wang M K Shyu C N Lee F J Hsieh 《Ultrasound in obstetrics & gynecology》2004,24(1):89-93
Larsen syndrome consists of skeletal dysplasia with multiple joint dislocations and a characteristic facies. The basis of this abnormality is a generalized mesenchymal disorder involving connective tissues. We describe our findings in a woman who was referred at 28 weeks' gestation due to multiple fetal anomalies suspected initially at an 18-week ultrasound examination. On three-dimensional (3D) ultrasound we found the fetus had bilateral genu recurvatum. Further 3D examination at 36 weeks confirmed the lower limb anomaly and revealed facial anomalies that led to the diagnosis of Larsen syndrome. An elective Cesarean section was performed at 38 weeks' gestation to minimize neurological sequelae. Magnetic resonance imaging was performed postnatally and showed pachygyria, colpocephaly and agenesis of the corpus callosum. In this case, 3D ultrasound facilitated the prenatal diagnosis of Larsen syndrome. A careful prenatal investigation for other associated anomalies such as those of the cardiovascular or neurological systems is warranted with this diagnosis. These associated lesions are likely to have a greater impact on prognosis than the classic symptoms of Larsen syndrome and a collaborative approach is necessary to optimize delivery and postnatal management of an affected fetus. 相似文献
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Pentoxifylline inhibits human peritoneal mesothelial cell growth and collagen synthesis: effects on TGF-beta 总被引:6,自引:0,他引:6
BACKGROUND: Prevention or treatment of peritoneal fibrosing syndrome has become an important issue in patients on continuous ambulatory peritoneal dialysis (CAPD). Recent evidence has suggested that mesothelial stem cell proliferation and matrix over-production predispose the development of peritoneal fibrosis. We investigated whether pentoxifylline (PTX) affects human peritoneal mesothelial cell (HPMC) growth and collagen synthesis. METHODS: HPMC was cultured from human omentum by an enzymic disaggregation method. Cell proliferation was assayed using a methyltetrazolium uptake method. Cell cycle analysis was performed by flow cytometry. Collagen synthesis was measured by 3H-proline incorporation into pepsin-resistant, salt-precipitated collagen. Prostaglandins and cAMP were determined by enzyme immunoassay. Northern blot analysis was used to determine mRNA expression. RESULTS: Our data show that PTX inhibited serum-stimulated HPMC growth and collagen synthesis in a dose-dependent manner. Cell cycle analysis showed that PTX arrested the HPMCs in the G1 phase. PTX decreased the procollagen alpha1 (I) mRNA expression either stimulated by serum or transforming growth factor-beta (TGF-beta). PTX did not alter prostaglandins synthesis but dose-dependently increased intracellular cAMP level. PTX, the same as 3-isobutyl-l-methylxanthine, could potentiate prostaglandin E1 (PGE1) increased cAMP levels of HPMC. The antimitogenic and antifibrogenic effects of PTX on HPMC were reversed by N-[2]-((p-Bromocinnamyl)amino)ethyl]-5-isoquinolinesulfonamide (H-89). Therefore, the mechanism of these effects may be due to the phospodiesterase inhibitory property of PTX. CONCLUSIONS: These data suggest that PTX may have a role in treating peritoneal fibrosing syndrome. 相似文献
9.
用二维核磁共振技术研究赤芝孢子内酯A和B的结构 总被引:4,自引:0,他引:4
通过~1H-~1H,~1H-~(13)C相关谱(COSY),~1H-~(13)C远程偶合相关谱(OOLOC)及NOE二维谱(NOESY)等新的二维核磁共振技术确定了两个新化合物赤芝孢子内酯A和B的结构。 相似文献
10.
目的:评价佳贝和欧可芬滴眼液在白内障术中维持瞳孔散大及术后抗炎作用疗效。胡机分组(佳贝组、欧可芬组和对照组)研究86名白内障患者术前应用两种药物后,白内障术中瞳孔大小的改变以及对卡米可林(氨甲酰胆碱,Carbacol)缩瞳作用的影响;以地塞米松滴眼液为对照,研究应用两种滴眼液对术后角膜后KP和房水混浊度的影响,以及对术眼眼压的影响。结果:与对照组相比,佳贝和欧可芬都能有效抑制术中的瞳孔缩小(P〈0 相似文献