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排序方式: 共有670条查询结果,搜索用时 15 毫秒
1.
A case of nontraumatic rupture of the ureter secondary to a nonopaque calculus is presented. Because of the inherent high image contrast caused by the leak of technetium 99m-DTPA-labeled urine, the technetium 99m DTPA excretory urogram is seen as an alternative to the intravenous urogram or contrast-enhanced computed tomography in selected cases of suspected ureteral rupture. 相似文献
2.
Digitoxigenin alpha-L-, beta-L-, alpha-D-, and beta-D-glucosides; alpha-L-, beta-L-, alpha-D-, and beta-D-mannosides; and alpha-L- and beta-L-rhamnosides were stereoselectively synthesized from the corresponding sugar tetrabenzyl trichloroacetimidates. The Na+,K+-ATPase receptor inhibitory activities of these glycosides (as a measure of receptor binding) were compared with those of digitoxigenin, digitoxigenin 6'-hydroxy-beta-D-digitoxoside, digitoxigenin beta-D-galactoside, and digitoxigenin beta-D-digitoxoside. The observed activities reveal that a given sugar substituent may have a role in binding of some glycoside stereoisomers, but not others. With alpha-L- and possibly beta-L-rhamnosides, the 5'-CH3 and 4'-OH appear to have a predominant role in binding to the Na+,K+-ATPase receptor. Addition of a 6'-OH to form the corresponding mannosides dramatically disrupts the effect of both the 5'-CH3 and 4'-OH in prompting receptor binding of the alpha-L isomer. However, with the beta-L isomer, some influence of 4'-OH, 3'-OH, and 2'-OH binding remains. With beta-D-glycosides, binding via the "5'-CH3 site" appears to be of little importance and addition of a 6'-OH diminishes activity only slightly. With these beta-D-glycosides, an equatorial 4'-OH, axial 3'-OH, and equatorial 2'-OH groups appear to contribute to binding. 相似文献
3.
Nadkarni JJ Perambakam SM Rathore VB Amin KM Parikh PM Naresh KN Advani SH 《Cancer biotherapy & radiopharmaceuticals》1998,13(4):269-274
The trafficking or homing of different lymphoid subsets to particular microenvironment is mediated by specific cell adhesion molecules (CAMs) expressed on lymphocytes and endothelial cells. B-cell chronic lymphocytic leukaemia (B-CLL) or Non-Hodgkin's lymphoma of small lymphocytic, B-cell type are monoclonal expansions of mature lymphocytes. The relative distribution of the tumor lymphocytes among various lymphoid compartments vary from patient to patient. Very few studies underlying this issue are available. To this effect, we have analysed the expression of LFA-1; VLA-4, ICAM-1; CD44H and CD44v6 (haematopoietic and variant form respectively) on freshly isolated lymphocytes obtained from bone marrow (BM), peripheral blood (PB) and lymph node (LN) by flow cytometry. Overall, we find strong expression of CD44H, low to moderate expression of LFA-1, negative to low expression of VLA-4 and lack of expression of CD44v6. ICAM-1 expression was observed only in patients with prominent lymphadenopathy. Higher expression of CD44H in PB lymphoid cells relative to that of BM lymphoid cells correlated with higher PB lymphocytosis (p < 0.001). Proliferating cell nuclear antigen expression in LN sections correlated inversely with VLA-4 expression on BM and PB lymphoid cells (p < 0.05). There was no significant correlation between expression of CAMs and bcl-2 protein. 相似文献
4.
Nachman SA Stanley K Yogev R Pelton S Wiznia A Lee S Mofenson L Fiscus S Rathore M Jimenez E Borkowsky W Pitt J Smith ME Wells B McIntosh K 《JAMA》2000,283(4):492-498
CONTEXT: Although protease inhibitors are used routinely in adults with human immunodeficiency virus (HIV) infection, the role of these drugs in the treatment of clinically stable HIV-infected children is not clear. OBJECTIVE: To evaluate the safety, tolerance, and virologic response produced by a change in antiretroviral therapy in HIV-infected children who were clinically and immunologically stable while receiving previous therapy. DESIGN: The Pediatric AIDS Clinical Trials Group 338, a multicenter, phase 2, randomized, open-label controlled trial conducted from February 6 to April 30, 1997 (patient entry period); patients were followed up for 48 weeks. SETTING: Pediatric HIV research clinics in the United States and Puerto Rico. PATIENTS: Two hundred ninety-seven antiretroviral-experienced, protease inhibitor-naive, clinically stable HIV-infected children aged 2 to 17 years. INTERVENTIONS: Children were randomized to receive zidovudine, 160 mg/m2 3 times per day, plus lamivudine, 4 mg/kg 2 times per day (n = 100); the same regimen plus ritonavir, 350 mg/m2 2 times per day (n = 100); or ritonavir, 350 mg/m2 2 times per day, and stavudine, 4 mg/kg 2 times per day (n = 97). MAIN OUTCOME MEASURE: Plasma HIV-1 RNA levels at study weeks 12 and 48, compared among the 3 treatment groups. RESULTS: At study week 12, 12% of patients in the zidovudine-lamivudine group had undetectable plasma HIV RNA levels (<400 copies/mL) compared with 52% and 54% of patients in the 2- and 3-drug ritonavir-containing groups, respectively (P<.001). Through study week 48, 70% of children continued receiving their ritonavir-containing regimen. At study week 48, 42% of children receiving ritonavir plus 2 nucleosides compared with 27% of those receiving ritonavir and a single nucleoside had undetectable HIV RNA levels (P = .04); however, similar proportions in each group continuing initial therapy had HIV RNA levels of less than 10000 copies/mL (58% vs 48%, respectively; P = .19). CONCLUSIONS: In our study, change in antiretroviral therapy to a ritonavir-containing regimen was associated with superior virologic response at study week 12 compared with change to a dual nucleoside analog regimen. More children receiving ritonavir in combination with 2 compared with 1 nucleoside analog had undetectable HIV RNA levels at study week 48. 相似文献
5.
Sachintha Perera Sudhir Rathore Joanne Shannon Peter Clarkson Matthew Faircloth Vinod Achan 《The British Journal of Cardiology》2022,29(1)
Presentation and outcomes of patients with ST-elevation myocardial infarction (STEMI) may change during viral pandemics. We compared symptom-tocall (STC), call-to-balloon (CTB), doorto-balloon (DTB) times; high-sensitivity troponin (hs-cTnI) levels; and survival of patients (n=39) during the first wave of the COVID-19 pandemic (defined as a ‘COVID period’ starting four weeks before lockdown) to historical controls from a ‘pre-COVID period’ (n=45).STEMI admissions fell one week before lockdown by 29%. Median STC times began to rise one month before lockdown (54 vs. 25 min, p=0.06), with peak increases between 9 March and 5 April (166 vs. 59 min, p=0.04). Median CTB and DTB times were unchanged. Mean peak hs-cTnI increased during COVID-19 (15,225 vs. 8,852 ng/ml, p=0.004). Six-month survival following all STEMI reduced (82.1% vs. 95.6%, p<0.05).STC times are the earliest indicator that STEMI-patient behaviour changed four weeks before lockdown, correlating with higher troponin levels and reduced survival. These early signals could guide public health interventions during future pandemics.Key words: COVID-19, outcomes, percutaneous coronary intervention (PCI), ST-elevation myocardial infarction (STEMI) 相似文献
6.
The utility of activated charcoal for the removal of malathion from saline waters has been explored. The adsorption capacity of charcoal for malathion has been found to be 117 mg g-1. Adsorption follows the Freundlich adsorption isotherms, the value of k and 1/n for charcoal being 1.6 and 0.60, respectively. Malathion can be eluted with methanol or ethanolic potassium hydroxide. 相似文献
7.
8.
BACKGROUND: We sought to evaluate the prognostic value of the 6-minute walk test in stable outpatients with heart failure. METHODS AND RESULTS: We examined the association of 6-minute walk test distance and outcomes among 541 patients enrolled in the Digitalis Investigation Group trial. Patients were grouped by total distance (< or =200 m, 201 m-300 m, 301 m-400 m, and >400 m) with median follow-up of 32 months. All-cause mortality for patients who walked < or =200 m was significantly higher than patients who walked >200 m (43.9% versus 23.3%, P<0.001), but mortality was comparable among patients who walked >200 m (201 m-300 m: 23.7%, 301 m-400 m: 25.2%, >400 m 19.8%, P for trend 0.45). Results were similar for death due to worsening heart failure (< or =200 m: 29.3%, 201 m-300 m: 7.6%, 301 m-400 m: 6.7%, >400 m: 6.1%, P for trend <0.001). In multivariable analysis, distance < or =200 m remained associated with increased mortality (< or =200 m: hazard ratio (HR) 1.47, 95% CI 0.96-2.27; >200 m: HR 1.00, Referent; P=0.07) and death due to worsening heart failure (< or =200 m: HR 2.89, 95% CI 1.54-5.41; >200 m: 1.00, Referent; P=0.001). CONCLUSIONS: The 6-minute walk test identifies patients who walk less than 200 m as being at markedly increased risk of death. Changing the 6-minute walk test to a time- and distance-based standard would improve the efficiency of the test while retaining the bulk of the prognostic information. 相似文献
9.
Background Amiodarone has been shown to be safe in patients with acute myocardial infarction (AMI) who are at risk for sudden cardiac death. However, there is limited data concerning the safety of amiodarone in patients who experience AMI complicated by atrial fibrillation. Methods To determine the safety of amiodarone therapy, we conducted a retrospective analysis of elderly patients hospitalized with AMI who experienced atrial fibrillation and had survived to hospital discharge (n = 17,597). Amiodarone prescribed at discharge was evaluated for its association with short-term and long-term mortality in crude and adjusted analyses employing propensity score methods. Results Of the 17,597 patients, 550 patients (3.1%) were prescribed amiodarone, 2317 patients (13.2%) were prescribed other antiarrhythmic agents (excluded from analysis), and 14,730 (83.7%) were prescribed no antiarrhythmic medication at discharge. Thirty-day mortality rates were similar for patients prescribed amiodarone and those not prescribed amiodarone (6.8% amiodarone vs 5.4% no amiodarone, P = .21), but mortality at 1 year was higher among patients prescribed amiodarone (35.6% vs 31.6%, P = .001). However, amiodarone was not associated with mortality at 30 days (odds ratio 0.80, 95% CI 0.53-1.20) or at long-term follow-up (mean duration 612 days, hazard ratio 1.04, 95% CI 0.92-1.18) after multivariable modeling. Conclusions Amiodarone was not independently associated with short-term or long-term mortality in elderly patients discharged after a hospitalization for AMI complicated by atrial fibrillation. Although our data suggest that amiodarone may be safe to use in this population, randomized controlled trial data are needed to confirm this finding. (Am Heart J 2002;144:1095-101.) 相似文献
10.
Foody JM Rathore SS Wang Y Herrin J Masoudi FA Havranek EP Radford MJ Krumholz HM 《American heart journal》2004,147(1):66-73