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李强  张昱苹  谢东 《海南医学》2002,13(3):18-20
目的:探讨高分辨率CT(HRCT)对颞部疾病的检查价值。方法:对43例颞部疾病患者行常规CT和高分辨率CT(HRCT)检查所获图像对比分析,并讨论HRCT的检查技术和图像后处理。结果:HRCT对病变的显示率及病变引起骨质破坏的程度,病变边缘,轮廓的显示均明显优于常规CT,尤其能清楚显示常规CT难以显示的中耳及内耳的细微结构,结论:高分辨率CT是颞部疾病的首选检查方法,使用高分辨率CT对颞部疾病的检查给临床提供更多,更准确的诊断信息。  相似文献   
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Intratemporal vascular tumors: detection with CT and MR imaging   总被引:1,自引:0,他引:1  
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion.  相似文献   
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 The behavioral effects of GBR 12909, a selective dopamine uptake inhibitor, were determined in squirrel monkeys trained to respond under a fixed-interval (FI) schedule of stimulus termination and a second-order schedule of IV drug self-administration. Intermediate doses of GBR 12909 increased FI response rate markedly, and the highest dose decreased response rate below control values. The 5HT uptake inhibitors, alaproclate and fluoxetine, and the 5HT agonist, quipazine, attenuated the behavioral-stimulant effects of GBR 12909, whereas the 5HT2A/2C antagonist, ritanserin, enhanced the behavioral-stimulant effects of the lowest dose. GBR 12909 reliably maintained self-administration, and ritanserin increased response rate maintained by the highest dose. The dopamine agonist, quinpirole, increased FI response rate in only one of three subjects, and ritanserin enhanced the behavioral-stimulant effects of quinpirole in that subject. The dopamine agonist, apomorphine, only decreased FI response rate, and ritanserin did not alter its behavioral effects. The pharmacological profile of GBR 12909 administered alone and in combination with selective 5HT drugs in the present study was similar to that obtained previously with cocaine, further demonstrating that 5HT can reliably modulate the behavioral effects of psychomotor stimulants with prominent dopaminergic actions. Received: 9 July 1996 / Final version: 22 November 1996  相似文献   
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The epidemiology of HIV infection in the US in general, and in the southeast, in particular, has shifted dramatically over the past two decades, increasingly affecting women and minorities. The site for our intervention was an infectious diseases clinic based at a university hospital serving over 1,300 HIV-infected patients in North Carolina. Our patient population is diverse and reflects the trends seen more broadly in the epidemic in the southeast and in North Carolina. Practicing safer sex is a complex behavior with multiple determinants that vary by individual and social context. A comprehensive intervention that is client-centered and can be tailored to each individual’s circumstances is more likely to be effective at reducing risky behaviors among clients such as ours than are more confrontational or standardized prevention messages. One potential approach to improving safer sex practices among people living with HIV/AIDS (PLWHA) is Motivational Interviewing (MI), a non-judgmental, client-centered but directive counseling style. Below, we describe: (1) the development of the Start Talking About Risks (STAR) MI-based safer sex counseling program for PLWHA at our clinic site; (2) the intervention itself; and (3) lessons learned from implementing the intervention.  相似文献   
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OBJECTIVE: To determine if conventional sperm parameters, specific characteristics of sperm motion determined by computer-aided semen analysis (CASA), sperm penetration assay (SPA), and/or spontaneous acrosome reaction assay could best predict fertility outcome after intrauterine insemination (IUI) from frozen donor sperm. DESIGN: A retrospective analysis of 2,245 cycles of therapeutic donor IUIs were initially studied; 1,147 cycles that met selection criteria were used in this report. SETTING: A university-based assisted reproductive technology center. PATIENTS, PARTICIPANTS: All IUIs were performed on women with documented patency of at least one fallopian tube, ovulatory cycles, and who did not receive human menopausal gonadotropins. Sperm donors had to be used for at least four different recipients (mean of 15) and at least 14 different cycles of insemination (mean of 41). INTERVENTIONS: None. MAIN OUTCOME MEASURE: Pregnancy. RESULTS: Statistical comparisons were made between donors of different relative fertility by using the Mann-Whitney test, Spearman's rank correlation, and multiple regression analysis. These analyses demonstrated that the most significant predictors of the fertility of frozen-thawed donor sperm were curvilinear velocity, straight line velocity, and the total number of motile sperm inseminated. The number of sperm with spontaneous acrosome reactions negatively correlated with fertility outcome, and SPA provided no predictive value. CONCLUSIONS: Our study supports the hypothesis that the study of sperm motion characteristics using CASA after thawing and washing of cryopreserved sperm is a better predictor of fertile outcome after IUI than analysis of fresh semen.  相似文献   
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骨巨细胞瘤的MRI诊断价值   总被引:10,自引:0,他引:10  
目的探讨骨巨细胞瘤的MRI表现特点及其病理基础。资料与方法搜集经手术病理证实的12例骨巨细胞瘤患者资料,分析其MRI征象并与病理结果对照。结果T1WI上肿瘤实体表现为低、等信号,T2WI上为不均匀高信号,Gd-DTPA增强扫描呈中度到明显强化。此外,MRI还可显示肿瘤内坏死、出血、含铁血黄素沉着等。结论MRI能够提供比较全面的影像学信息,可提高对骨巨细胞瘤诊断的准确性。  相似文献   
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OBJECTIVE: To test, using a primate model, a new approach for achieving individualized pituitary-ovarian responses to controlled ovarian hyperstimulation. DESIGN: Normal ovulatory adult monkeys were selected and randomly assigned to one of the three groups according to onset of spontaneous menses. They had no prior exposure to gonadotropin-releasing hormone (GnRH) antagonist or exogenous gonadotropin therapies. SETTING: The laboratories of The Jones Institute for Reproductive Medicine were used. PATIENTS, PARTICIPANTS: Normal adult macaque females were studied. INTERVENTIONS: Monkeys received hormonal therapies of gonadotropins in combination with GnRH antagonist. MAIN OUTCOME MEASURE(S): Pituitary luteinizing hormone (LH) secretion and ovarian estrogen and progesterone production were monitored. RESULTS: Adding GnRH antagonist to ongoing human follicle-stimulating hormone (hFSH) stimulation can prevent unwanted LH surges, whether begun at early, mid, or late points in the stimulation protocol. CONCLUSIONS: The flexible protocol for administration of hFSH with GnRH antagonist yielded satisfactory results, with apparent advantages of economy, convenience, and individuality of treatment compared with GnRH agonist plus gonadotropin regimens used currently.  相似文献   
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Asthma affects 5%-10% of adults in the United States. Older adults (> 65 years) with asthma have higher rates of fatal asthma than younger adults. The occurrence of a respiratory emergency, such as status asthmaticus, would seem likely to create a situation of cardiopulmonary dysfunction conducive to myocardial ischemia. However, multiple studies of fatal or near-fatal asthma have failed to incriminate myocardial infarction as a contributing factor. We report a patient without underlying coronary artery disease who sustained myocardial injury consistent with myocardial ischemia and infarction during status asthmaticus while receiving recommended treatment without intravenous sympathomimetics or theophylline.  相似文献   
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