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排序方式: 共有594条查询结果,搜索用时 15 毫秒
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.
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
4.
David H. VanDercar Arthur R. Laperriere Liang Yu Shyu Michael F. Ward Philip M. McCabe Arlette Perry Neil Schneiderman 《Psychophysiology》1988,25(6):703-711
A microcomputer automated system for measuring systolic time intervals is described. Electrocardiogram, phonocardiogram, and carotid pulse tracings were measured in 38 healthy male subjects during baseline conditions and during either exercise on a bicycle ergometer or a video-game task. These measurements were recorded on both a traditional 3-channel ECG recorder and the computerized system. Both methods of recording systolic time intervals were independently scored by two different experimenters. In this way, interrater reliability of hand-scoring, intermethod reliability between hand-scoring versus computer-scoring, and interrater reliability of computer-scoring could be assessed. The interrater reliabilities of hand-scored systolic time intervals were generally above .90, ranging from .73 for left ventricular ejection time to .99 for R-R intervals of the ECG, with a mean of .92. The intermethod reliability of the computer versus hand-scored systolic time intervals also proved to be generally above .90, ranging from .76 for S1-S2 components of the phonocardiogram to .99 for R-R, with a mean of .94. The interrater reliabilities of the computer-scored systolic time intervals were all above .90, ranging from .93 for S1-S2 to .99 for R-R, with a mean of .98. These data indicate that the computerized method of scoring systolic time intervals is at least as reliable as the more traditional scoring of paper tracing. 相似文献
5.
6.
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
7.
Chen CM Chen CJ Chang CL Shyu JS Hsieh HF Harn HJ 《The Journal of surgical research》2000,94(2):84-91
BACKGROUND: This study investigated the immunophenotypic patterns of CD34, CD117 (a product of the c-kit proto-oncogene), and actin (HHF35) in benign and malignant phyllodes tumors (PTs). We correlated the expression of CD34, CD117, and actin with histopathological grade. MATERIALS AND RESULTS: We analyzed 19 cases (7 benign and 12 malignant cases) of PTs using immunohistochemical analysis. Six of 7 benign PT stromal lesions stained positively for CD34, while only 3 of 12 cases of malignant PT were focally CD34 positive (P = 0.0106). Only 1 of the 7 benign PTs stromal lesions expressed CD117. Nine of the malignant PTs were composed CD117-positive fibroblasts. This result demonstrated that CD117 expression is associated with the malignant potential of PTs (P = 0. 0106). Actin (HHF-35) expression was found in 8 of 12 cases of malignant PTs (P = 0.027), but in only 1 of 7 cases of benign PTs. Actin expression was significantly (P = 0.04) correlated to frequent mitotic activity (>5 mitoses per 10 high-power fields). The immunophenotypic markers were not related to tumor size. Additionally, we sequenced part of the juxtamembrane region of the c-kit proto-oncogene and found point mutations in two malignant PTs. CONCLUSION: Our results demonstrated that expression of CD34 was associated with benign PTs, while CD117 and actin were preferentially expressed in malignant PTs. Our results implied that these immunohistological markers might be used for the histopathological grading of PTs. 相似文献
8.
9.
Yi-Wei Yeh Pei-Shen Ho Shin-Chang Kuo Chun-Yen Chen Chih-Sung Liang Che-Hung Yen Chang-Chih Huang Kuo-Hsing Ma Chyng-Yann Shiue Wen-Sheng Huang Jia-Fwu Shyu Fang-Jung Wan Ru-Band Lu San-Yuan Huang 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(7)
Background:
Many lines of evidence suggest the role of serotonin transporter (SERT)-mediated reuptake of serotonin in the pathophysiology and treatment of major depressive disorder (MDD). This study aimed to examine whether the pretreatment of SERT binding potential or SERT binding ratio between terminal projection regions relative to the midbrain raphe nuclei was associated with treatment outcomes to SERT-targeted antidepressants.Methods:
We recruited 39 antidepressant-naïve patients with MDD and 39 heathy controls. Positron emission tomography with N,N-dimethyl-2-(2-amino-4-[18F]fluorophenylthio)benzylamine (4-[18F]-ADAM) was used to measure in vivo SERT availability prior to antidepressant treatment. The 21-item Hamilton Depression Rating Scale (HDRS) was use to assess the severity of depression from baseline to week 6. All the patients with MDD had HDRS scores of 18 or more.Results:
Pretreatment SERT binding in the thalamus and striatum positively correlated with an early reduction in HDRS scores at week 3. Nonresponders and dropout patients showed a proportionate reduction in SERT binding in the terminal projection regions and midbrain compared to healthy controls. In contrast, a disproportionate reduction in SERT binding in the terminal projection regions relative to midbrain was observed in responders.Conclusions:
The results of this study suggested that a disproportionate reduction in SERT binding between terminal projection regions and midbrain may predict better treatment outcomes in patients with MDD. 相似文献10.
OBJECTIVE: Amphetamine has been known to induce cardiac dysrhythmia and sudden death. However, the molecular mechanism for the induction of dysrhythmia is not known. Connexin43 (Cx43) plays an important role for arrhythmogenesis. This study was undertaken to test the hypothesis that amphetamine could induce Cx43 expression in cardiac myocytes. METHODS: Neonatal Wistar rat cardiac myocytes were cultured under the stimulation of amphetamine. Cx43 mRNA and protein expression were examined by Northern and Western blots, respectively. We used c-Jun N-terminal kinase (JNK) inhibitor, SP600125, and JNK1 dsRNAi to investigate the signal pathway of amphetamine-induced expression of Cx43. RESULTS: The level of Cx43 protein significantly increased from 4 to 24 h after addition of amphetamine (10 microM). The Cx43 mRNA increased maximally to 4.2-fold at 6 h after addition of amphetamine and returned to the baseline level at 48 h. These increases of Cx43 protein at 24 h were completely attenuated (P<0.001) by SP600125 (20 microM) and JNK1 dsRNAi. Amphetamine increased and SP600125 decreased the immunohistochemical labeling of Cx43. Amphetamine increased and SP600125 decreased the phosphorylated JNK and c-Jun proteins. Gel-shifting assay showed that DNA-binding activity of AP-1 increased after addition of amphetamine and SP600125 and JNK1 dsRNAi abolished the binding activity induced by amphetamine. CONCLUSIONS: These findings indicate that amphetamine activates Cx43 gene expression in cultured rat neonatal cardiac myocytes. Amphetamine mediates the Cx43 gene expression, at least in part, through the JNK pathway. These findings from our study suggest that Cx43 plays a role for the molecular mechanism of amphetamine-induced cardiac dysrhythmias. 相似文献