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991.
992.
目的 应用体素内不相干运动扩散加权成像(IVIM-DWI)比值法鉴别诊断前列腺移行区的前列腺疾病,并对前列腺癌(PCa)进行风险评估。方法 纳入97例前列腺疾病病人,包括经超声引导穿刺活检或术后病理证实为发生于移行区的PCa病人35例[平均年龄(65.4±9.3)岁]和良性前列腺增生(BPH)病人62例[平均年龄(61.2±10.8)岁],并进行肿瘤组织Gleason评分。根据Gleason评分确定PCa是否具有临床意义,并进行高低风险划分。所有病人均行IVIM-DWI检查,测量前列腺移行区表观扩散系数(ADC)和纯扩散系数(D)值,计算病灶区与对侧非病灶区相应2个参数的比值(ADCratio和Dratio)。采用独立样本t检验比较2组间ADCratio和Dratio的差异。采用受试者操作特征(ROC)曲线评估ADCratio和Dratio的诊断效能。结果 PCa组病灶区的ADC值和D值均低于对侧非病灶区(P<0.05),而BPH组病灶区ADC值、D值与对侧非病灶区的差异无统计学意义(均P>0.05)。PCa组的ADCratio和Dratio值均小于BPH组(均P<0.05)。PCa高风险组的ADCratio和Dratio均低于低风险组(均P<0.05)。ADCratio为0.782时鉴别移行区PCa和BPH的ROC曲线下面积(AUC)更高(0.925),其敏感度、特异度和准确度分别为91.2%、89.0%、90.1%; ADCratio为0.707时鉴别有无临床意义PCa的AUC更高(0.846),其敏感度、特异度和准确度分别为80.2%、91.1%、87.4%。结论 通过IVIM-DWI比值法计算得出的ADCratio和Dratio对移行区PCa有较高的诊断价值,同时能够在一定程度上预测Gleason分级,但尚不能在临床治疗中代替穿刺活检。  相似文献   
993.
BACKGROUND: Percutaneous balloon mitral valvuloplasty (PBMV) has become the procedure of choice for isolated, uncomplicated mitral stenosis (MS) with favorable morphology and may be a useful method for surgical high-risk conditions such as advanced age, the presence of severe tricuspid regurgitation, New York Heart Association (NYHA) class IV at presentation, and severe pulmonary hypertension (PH). The development of PH is a common and important sequela in patients with advanced mitral stenosis and is associated with hemodynamic and clinical decompensation. However, the influence of PBMV on patients with severe PH has seldom been evaluated. Our objective was to probe into the immediate and long-term effects of PBMV on patients with MS complicated by severe PH and to predict the factors that determine the prognosis of patients with severe PH. METHODS: We included 44 patients with MS complicated by severe PH (systolic pulmonary pressure >80 mm Hg, group S) and 67 patients with MS complicated by mild PH (systolic pulmonary pressure <50 mm Hg, group M) in this study and we compared their immediate and late results after a follow-up period of 24 months after PBMV. RESULTS: Compared with group M, patients in group S were older, presented more frequently with NYHA III-IV class, valvular echo score >or=8, and more severe tricuspid regurgitation, and had a bigger left atrial diameter before PBMV. The successful rate and the incidence of severe complications from the PBMV procedure were similar in both groups. There were more cases of post-PBMV mitral valve area >or=1.5 cm(2) in group M than in group S, and the average mitral valve area in group M was somewhat larger than that of group S. After PBMV, NYHA class obviously improved in both groups, but there were more patients with NYHA0.05). NYHA class I or II was present for 80.6% in group M and 59.1% in group S (p<0.10). RESULTS: PBMV is a safe and effective procedure for patients with severe PH. It can remarkably improve clinical outcomes, although hemodynamic effects of PBMV on this subgroup are not complete. Pre-existing older age, more severe valvular lesion and tricuspid regurgitation, worse cardiac function, and bigger left atrial size in patients with severe PH may be important risk factors for the poor hemodynamic outcomes of PBMV.  相似文献   
994.
OBJECTIVE: To determine HIV seroincidence, study participant retention rate, and baseline predictors of HIV incidence and study retention among high-risk injection drug users (IDUs) in Xinjiang, China. METHODS: A total of 508 eligible seronegative high-risk IDUs were enrolled. Study participants were tested for HIV-1 and counseled at the baseline, 6-month, and 12-month follow-up visits. Sociodemographic and behavioral data were collected during each study visit. The HIV-1 incidence rate and the retention rate were analyzed as a function of sociodemographic, behavioral, and recruitment variables. RESULTS: At 12 months of follow-up, the HIV-1 incidence rate was 8.8 per 100 person-years (95% CI 6.3-12.0%) and the participant retention rate was 93%. Marital status at baseline was the only predictor of HIV incidence. No baseline variables were predictive of study retention. CONCLUSIONS: HIV incidence is high among IDUs in Xinjiang, China. Baseline predictors of incidence and retention were minimal. The participant retention rate in this study is promising for the undertaking of future HIV intervention studies.  相似文献   
995.
996.
BACKGROUND AND AIM OF THE STUDY: Perturbations of leaflet geometry are the final end point through which left ventricular (LV) ischemia causes incomplete mitral leaflet closure and resultant mitral regurgitation (MR). Geometric inconsistencies observed with valvular or subvalvular structural alterations raise several questions. METHODS: A new in-vitro LV flexible bag model was developed in order to visualize and analyze leaflet geometric changes under simulated pathological ischemic MR conditions. RESULTS: Papillary muscle (PM) displacement and annular dilatation decreased leaflet coaptation length, leading to significant MR. Symmetrical PM displacement shifted the coaptation line towards the leaflet edges and created central gaps along this line. Asymmetric PM displacement generated diametrically uneven coaptation with a tent-shaped leaflet at the tethered PM side, while the leaflet bulged at the opposite side towards the left atrium. CONCLUSION: Leaflet geometry during systole is affected by subvalvular structures. Asymmetric PM displacement, which may occur in regional or acute myocardial infarction, induces irregular deformation of the leaflet's coaptation line and, as a result, MR at the tethered side. Direct visualization of leaflet perturbation under these simulated pathological conditions may promote understanding of mechanisms present in ischemic MR.  相似文献   
997.
In order to increase our knowledge and understanding about multilocular cystic renal cell carcinoma (MCRCC), including diagnosis, surgical management, pathologic and prognostic characteristics, clinical data of patients who suffered with MCRCC were reviewed retrospectively. From 1998 to 2005, among 770 patients diagnosed with renal cell carcinoma (RCC) at our institute, 31 cases (4.0%) were identified as MCRCC. The average age of patients suffered with RCC and MCRCC was 58.1 ± 3.6 and 45.9 ± 2.7, respectively (P < 0.01), whereas the gender ratio of male to female in RCC and MCRCC is 2.12:1 and 2.88:1(P < 0.01). Surprisingly, 28 of those 31 renal masses (90.3%) were first discovered on the radiographic image, and the size of tumors in maximum diameter ranged from 1.7 to 11.0 cm (mean 4.1 ± 2.2 cm). All those patients were treated with open nephrectomy, including 21 radical and 10 partial. The stages of tumor were classified as pT1N0M0, pT2N0M0, and pT3bN0M0 following the 1997 criteria of tumor-node-metastasis (TNM) classification in the number of 27(87.1%), 3(9.7%) and 1(3.2%), respectively. By contrast, according to the tumor nuclear grading system, those tumors were classified as Grades 1 and 2 in 13 (42%) and 18 patients (58%), respectively. Only 29 cases from those patients have been followedup for a period of 9 to 81 months so far (mean 32.6 ± 11), while no tumor recurrence occurred except for 1 case who died of causes other than MCRCC. In general, MCRCC is a frequent subtype of RCC in the clinic. A nephron-sparing procedure should be considered in the preoperative plan when a complex multicystic renal mass with enhanced density is observed.  相似文献   
998.
Men who have sex with men (MSM) may account for an increasing proportion of China’s HIV epidemic, but remain difficult to access for epidemiological studies due to high stigma. We compare the composition of two samples of MSM obtained in Guangzhou, China. The first survey, conducted in 2004, recruited MSM through convenience sampling. The second survey in 2006 used long-chain referral recruitment in the context of respondent-driven sampling. Compared to convenience sampling, the long-chain referral method included higher proportions of subgroups of MSM thought to be at elevated risk for HIV infection and more difficult to reach, including internal migrants and those engaging in commercial sex. Long-chain referral also recruited more MSM who were under 25 years, unemployed, and had lower education. We conclude that long-chain referral recruitment will be more effective in tracking the leading edge of the epidemic among MSM in China than convenience sampling.  相似文献   
999.
1000.
中国肝病患者血清铜蓝蛋白水平的研究   总被引:5,自引:1,他引:5  
目的 探讨我国不同肝病患者血清铜蓝蛋白 (CP)水平交叉程度 ,为肝豆状核变性(WD)的诊断和鉴别诊断提供科学的依据。方法 测定 90 5例正常人、WD及其他各种肝病患者血清CP水平 ,采用SPSS12统计软件进行统计分析。结果 WD患者血清CP平均为 (93 9± 98 1)mg/L ,与其他各组相比差异有非常显著性 ,72 7%的患者低于 10 0mg/L ,其中 4 2 9%的患者低于 5 0mg/L ,但是也有 9 1%的患者其血清CP正常 ,其中 3例高于 4 0 0mg/L ,最高达 5 0 1mg/L。 6 8%的非WD患者血清CP低于正常 ,最低为 2 8mg/L。急性肝炎患者血清CP平均为 (398 4± 15 1 3)mg/L ,显著高于其他各组。重型肝炎患者血清CP平均为 (2 96 5± 10 6 5 )mg/L ,显著低于其他各组 ,其中18 8%的患者低于正常。结论 WD患者CP水平显著低于正常人和其他肝病患者 ,但是与其他肝病有一定程度的交叉 ,单凭CP水平不足以确诊或排除WD。  相似文献   
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