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The short and long term efficacy of diltiazem, a calcium-entry blocker, has been evaluated in a group of ten patients with Prinzmetal's variant angina admitted to a CCU. In the short term part of the study, after a run-in period, diltiazem 60 mg tid and placebo were administered alternatively during 4 randomized 72 hour periods. Response was assessed using continuous Holter monitoring, measuring the frequency of transient ischemic attacks. During the run-in period the number of episodes/day/patient was 16.1. No episodes of transient ST segment elevation were recorded during both periods of diltiazem treatment in 3 patients and during one of the two periods in 4. For the group as a whole the number of episodes during the first placebo period was not statistically different from that during the run-in period (208 versus 161). No statistically significant difference was also found in 8 patients comparing the number of episodes during the second placebo period and the run-in period (166 versus 101). During each period of diltiazem treatment an highly significant reduction in the number of episodes was observed (43 and 5, p = .006 and p = .02). Two patients did not complete the study protocol. Both patients had a worsening of angina during the first placebo period following diltiazem treatment. One of them developed an acute myocardial infarction. The possible occurrence of a rebound phenomenon after withdrawal of diltiazem seems to be indicated, in 6 patients, by a significant increase in the number of ischemic episodes recorded during the placebo period following active treatment in respect to the number during the first placebo period (159 versus 73, p = .04).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
OBJECTIVES: We sought to compare the prognostic value of pharmacological stress echocardiography (SE) in diabetic and nondiabetic patients with known or suspected coronary artery disease. BACKGROUND: Although SE is a useful tool for risk stratification of patients with diabetes, it has not been established whether it retains the same prognostic information in diabetic patients compared with nondiabetic patients. METHODS: A total of 5,456 patients (749 diabetics) undergoing dipyridamole (n = 3,306) or dobutamine (n = 2,150) SE were prospectively followed up for the occurrence of hard events (death and/or nonfatal myocardial infarction). RESULTS: During a median time of 31 months, 411 deaths and 236 infarctions occurred. There were 132 events in diabetic patients and 515 in nondiabetic patients (18% vs. 11%, respectively; p < 0.0001). Moreover, 1,607 (29%) patients underwent coronary revascularization and were censored. Ischemia at SE, resting wall motion score index, and age were independent predictors of death and hard events in both diabetic and nondiabetic patients. Compared with a normal test, ischemia and scar test patterns were associated to significantly lower age-corrected five-year hard event-free survival in diabetic as well as nondiabetic patients. However, a normal test was associated with a greater than two-fold annual event rate in diabetic patients as compared with nondiabetics who were either younger (2.6% vs. 1.0%) or older (5.5% vs. 2.2%) than 65 years of age. CONCLUSIONS: Stress echocardiography is equally effective in risk stratifying diabetic and nondiabetic patients independently of age. However, the normal test result predicts a less favorable outcome in diabetic than in nondiabetic patients.  相似文献   
4.
A new immunochromatographic rapid test (Rapid Check HIV 1 and 2; Núcleo de Doen?as Infecciosas) for the detection of antibodies to human immunodeficiency virus type 1 and type 2 in human samples (whole blood, serum, and plasma) was evaluated and compared to the commercially available Determine (Abbott Laboratories). When whole-blood samples were evaluated, the specificity and sensitivity of both tests were 100%. However, when plasma samples were used, sensitivity for the Rapid Check HIV 1&2 and the Determine tests were 100 and 98.58%, respectively. The observed specificity for plasma samples was 98.94% for the Rapid Check HIV 1&2 and 96.97% for the Determine test. The results presented here are encouraging and support the adoption of both tests as an alternative to enzyme-lined immunosorbent assay and/or Western blots in regions where laboratorial infrastructure is not available or for use in the management of occupational accidents for healthcare workers.  相似文献   
5.
In order to determine if patients with a history of previous urothelial cell carcinoma (UCC) but with current normal urinary cytology have DNA damage in urothelial cells, the single-cell gel electrophoresis (comet) assay was conducted with cells obtained by urinary bladder washings from 44 patients (28 with a history of previous UCC). Increased DNA damage was observed in cytologically "normal" urothelial cells of patients with a history of UCC when compared with referents with no similar history and after correcting the data for smoking status and age (P < 0.018). Increased DNA damage also correlated with the highest tumor grade, irrespective of time or course of the disease after clinical intervention (Kendall tau correlation, 0.37, P = 0.016). Moreover, aneuploidy, as assessed by DNA content ratio (DCR; 75th/25th percentile of total DNA fluorescence of 50 comets/patient) was unaltered by smoking status, but increased with UCC grade: 1.39 +/- 0.12 (median +/- 95% confidence interval; referents); 1.43 +/- 0.11 (Grade I UCC; P = 0.264, against referents); 1.49 +/- 0.16 (Grade II UCC; P = 0.057); 1.57 +/- 0.16 (Grade III UCC; P = 0.003). Micronucleated urothelial cells (MNC) were also scored on Giemsa-stained routine cytological smears and were found not to correlate with DNA damage or DCR. MNC frequencies were higher for patients with a history of UCC and/or smoking than referents with neither history, but there was no statistical difference between groups. Taken together, these results suggest that the normal-appearing urothelium of patients resected for UCC still harbor genetically unstable cells.  相似文献   
6.
Previously we reported the majority of lesions induced by bilereflux, in the absence of chemical carcinogens, in the rat remnantstomach to consist primarily of gastric type and secondarilyof intestinal type cells, and that they are reversible afterdiversion of bile reflux. The present study was designed toevaluate changes in proliferative activities in cells of eachtype under these conditions. The frequency of adenomatous hyperplasia(AH) induced in the gastric stump mucosa by duodenal contentreflux after Billroth II partial gastrectomy (BII) increaseduntil the 54th week of the experiment. Roux-en-Y (RY) surgicalprocedure which prevents duodenal reflux performed at the 24thor 36th week after BII led to a decrease in AH. Cell contentof the lesions was analyzed using routine H&E staining,immunohistochemical staining for pepsinogen isoenzyme 1 andhistochemical procedures for mucins (paradoxical concanavalinA, galactose oxidase Schiff and sialidase galactose oxidaseSchiff reactions) and proliferation in each compartment evaluatedby an immunohistochemical method using bromodeoxyuridine (BrdU)and a monoclonal antibody against BrdU. At the 54th week thenumber of BrdU-labeled cells per normal pyloric column was significantly(P < 0.05) increased to 10.63/pit after the BII operation,while it diminished to 5.23/pit after RY diversion, this beingthe same level as with the RY procedure alone. AH maintaineda high rate of BrdU incorporation at 12.7% after BII operation,which was also significantly reduced (P < 0.01) to 7.0% bythe RY surgery. The intestinal type cell showed highest (22.2%),the surface mucous type cell showed the next (16.5%) and thepyloric gland type cell showed lowest (5.2%) BrdU labeling indicesafter BII operation. All the cell types in AH showed similarproportional decreases in BrdU incorporation after RY diversion.Thus surgical intervention reverses the cell proliferation causedby bile reflux in the gastric stump.  相似文献   
7.
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to evaluate the chlorhexidine gluconate (CHG) susceptibility in both planktonic cells and biofilm of...  相似文献   
8.
The aim of this randomized study was to determine the effects of octreotide therapy on the growth and development of experimental liver metastases from a human colonic cancer cell line (HT 29) in nude mice model. No important and significant difference could be found between mice, lungs and liver weights of both groups as well as lung metastatization; indeed, significant was the difference between groups concerning liver, metastases (the majority of them were in treated group): in spite of the small number of data collected, which does not allow to draw any conclusion on the efficacy of this drug on liver metastases, we believe that octreotide therapy does not affect dramatically the growth and development of liver metastases from a human colon cancer.  相似文献   
9.
Assessment of exercise capacity has been widely used in the evaluation of chronic heart failure (CHF), both to define the severity of the syndrome and to assess the changes induced by therapy. Various exercise tests and protocols can be used. The simple stress test using the exercise bicycle or the treadmill can give useful indications only in patients with severe or lower functional reductions. Maximum exercise duration usually depends on the patient's and the physician's motivation. The addition of respiratory gas exchange measurements, maximum oxygen consumption (VO(2)) or anaerobic threshold, increases the exactness of the assessment of the exercise limitation in CHF. VO(2) maximum provides an objective marker of aerobic capacity and it is biased by neither the patient nor the physician. This technique, however, requires the patient to exercise to exhaustion, and it is somewhat subjective and not indicative of normal daily exercise routine. The anaerobic threshold is a useful way of evaluating adaptability to submaximal efforts and the impact of the therapy on the daily performance. Nevertheless, it is significantly influenced by the fitness level and it has a reduced prognostic capability compared to VO(2) maximum. Submaximal exercise tests discriminate particularly between patients with severe CHF. The major limits are the influence of the patient's motivation and its limited validation in terms of reproducibility and prediction in controlled surveys.  相似文献   
10.
The fluorescent calcium-sensitive indicators, such as the Calcium Green-1, allow one to detect small calcium transients at low indicator concentrations. The protocol reported here is a rapid and sensitive method that facilitates the measurement of intracellular free-calcium in cell suspensions. Using this assay, we were able to detect and quantify the variations in intracellular calcium concentration during microglial cell activation induced by the fragment peptides beta25-35 and PrP106-126.  相似文献   
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