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91.
92.
OBJECTIVE: The purpose of this study was to describe the sociodemographic and serologic profiles in a first time consultant population at the Information and AIDS Prevention Center of Valencia (Spain). In addition, the HIV infection risk factors were analyzed. METHOD: A cross-sectional study was performed on 1,573 persons who consulted during the year 1995. Sociodemographic and infection risk practices data were recorded and serologic information about HIV, HBV and HCV infection were obtained. Exact binomial method with a 95% interval confidence was used to calculate infection prevalence and the chi square test to make comparisons between qualitative variables. RESULTS: Sex distribution was 66,1% males and 31,9% females; mean age was 29,01 (SD: 9.2) years. Sexual intercourse without condom (25.2%) and parenteral drug abusers (22.6%) were the more frequent risk groups seeking consultation about HIV infection. Global HIV infection prevalence was 12.7% (95% CI= 11,2-14,5%). Among HIV seropositive patients, sexual transmission accounted for 30.8% of cases, of which 69.4% were heterosexual relations. The HIV infection prevalence for different risk groups were the following: parenteral drug abusers 36.8% (95% CI= 31,7-42%), heterosexual intercourse with an HIV-infected partner 24.1% (95% CI= 17,1-32,2%) and homosexual intercourse between men 9,5% (95% CI= 5,8-14,5%). HCV antibody prevalence for parenteral drug abusers was 81.2% (95% CI= 76,7-85,1%). Risk practices with a statistically significant association with HIV infection were: being an injecting drug abuser, as well as having an HIV infected and/or a injecting drug abuser partner. CONCLUSIONS: Drug parenteral abusers are still the target population for prevention programs. Data suggest that prevention and sexual education programs must continue. The main effort should be focused on the young population and on sexual partners of injecting drug abusers and/or HIV seropositive partners.  相似文献   
93.
BACKGROUND: Optical penalization (OP) has previously been shown to successfully maintain vision in amblyopic eyes of older children when patching compliance is poor and when vision decreases once patching is discontinued. This study shows that the final vision in optically penalized eyes is often better than the vision obtained after patching alone. SUBJECTS AND METHODS: During the 5-year period from January 1992 to February 1997, 28 children aged between 3.7 and 8.2 years (average age, 6.5+/-1.1 years) were optically penalized for an average of 1.5+/-0.75 years. The maximum length of penalization was 3.3 years, whereas the minimum time was 6 months. There were 21 children with strabismic amblyopia and 7 children with anisometropic amblyopia. All 28 children had worn a patch to achieve their best visual levels and then had shown a loss of best vision when occlusion was stopped. Patching was usually resumed and continued until the previous best vision was obtained; at this point OP was started to "maintain" vision. Eighteen of the 28 children have discontinued penalization and have been followed up an average of 1(1/2) years. RESULTS: Twenty-six (93%) of the 28 patients showed an increase in best vision from that found at the conclusion of patching, and 2 patients maintained their vision at the initial level. The average visual acuity at the start of penalization was 20/50 (0.42+/-0.11 logarithm of the minimum angle of resolution [log MAR]). Final average visual acuity was 20/27 (0.15+/-0.12 log MAR). The average increase in vision was nearly 3 lines or 0.27+/-0.12 log MAR. CONCLUSION: OP alone (without the use of pharmacologic agents such as atropine) not only maintains vision after patching therapy, but also appears to improve the final visual outcome.  相似文献   
94.
A randomized open-label clinical trial was conducted to determine whether mortality, readmission, or quality of life differed between heart failure patients managed with captopril plus diuretics and those with digoxin plus diuretics. A total of 345 heart failure patients in New York Heart Association functional classes 2 and 3 without atrial fibrillation, dyspnea of bronchopulmonary origin, or hypertension not controlled with diuretics was randomized for digoxin (n = 175) or captopril (n = 170) treatment and followed up for a median of 4.5 years. Socioeconomic, demographic, electrocardiographic, echocardiographic, spirometric, and chest radiograph data were obtained at the initial examination. In a random sample of half the patients, ergometric, echocardiographic, and Holter records were obtained at entry and at 3 and 18 months. Patients were followed up for > or = 3 years. The end points were mortality, hospitalization for cardiac events, deterioration in quality of life, worsening of functional class, and need for digoxin or captopril in the captopril and digoxin groups, respectively. The trial had to be terminated prematurely owing to the difficulty in finding candidates free of angiotensin-converting enzyme (ACE)-inhibitor treatment. Baseline patient characteristics were similar in both groups. From the clinical point of view, only the 48-month mortality was relevantly lower (20.9 vs. 31.9%, respectively) among patients treated with captopril than that in those receiving digoxin (log rank test, p = 0.07). No statistically or clinically relevant differences were found in other end points or adverse effects. The results suggest but do not confirm the hypothesis that captopril treatment in mild to moderate heart failure might provide better long-term survival than digoxin.  相似文献   
95.
AIMS: To study the efficacy of omeprazole triple therapy in the eradication of Helicobacter pylori in patients with active gastric ulcer, and to assess healing and relapse of gastric ulcer. METHODS: A double-blind, randomized study was carried out in 18 centres in Germany, Hungary and Poland. Patients (n = 160) with gastric ulcer and a positive H. pylori screening test were randomized to a 7-day twice daily treatment with omeprazole 20 mg, clarithromycin 500 mg and amoxycillin 1000 mg (OAC) or omeprazole 20 mg, clarithromycin 250 mg and metronidazole 400 mg (OMC), or with omeprazole 20 mg once daily (O). After completion of this 1-week treatment, patients were treated with omeprazole until healing (maximum 12 weeks), and followed for 6 months. H. pylori was assessed by urea breath test (UBT) and histology. RESULTS: Eradication rates ITT were OAC 79% (95% CI: 65-90%), OMC 86% (95% CI: 73-94%) and O 4% (95% CI: 0-14%). Eradication rates PP were OAC 83% (95% CI: 68-93%), OMC 93% (95% CI: 80-98%) and O 3% (95% CI: 0-13%). Gastric ulcer relapses occurred in 5, 0 and 11 patients in the groups, respectively. CONCLUSIONS: The results from the study demonstrate that OMC and OAC 1-week regimens are safe and effective for eradication of H. pylori in gastric ulcer patients, and that ulcer relapse is infrequent after successful eradication.  相似文献   
96.
Summary The authors studied the behavior of normal subjects and paranoid schizophrenic patients in a simple problem-solving situation. The schizophrenics were divided into two sample groups, one of individuals under treatment and the other of individuals not under treatment.The learning process involved in this problem-solving situation is very similar to an instrumental conditioning, and can be understood by means of the following assumptions: (1) the subjects use decision functions in reacting to the stimuli, although they may be not fully aware of this; (2) learning is the result of successive transformations of these decisions in the course of time; (3) the changes have specific probabilities and are related to (a) those responses which are made to the latest stimuli, and (b) a differential probability for decision functions which were effective, or only interrupted painful reinforcement, or were completely ineffective.In schizophrenics further factors of importance were (1) an inertia factor and (2) the rigidly continued use of unsuccessful or only partially successful decision criteria.The authors used a systems theory based on Galois field theory and a calculus of operators specifying three groups of subjects. A computer program based on these hypotheses was tested in a simulation experiment.The statistical evaluation of the results showed a congruence between the theoretical approach and the experimental data.This work was carried out with financial support from the Institute de Alta Cultura, Lisbon, between 1970 and 1974  相似文献   
97.
The response of tumours to adriamycin, and the cardiotoxicity of the drug, may be related to its pharmacokinetics and plasma levels. Rapid and sensitive methods of adriamycin determination in plasma and urine samples are thus needed. A comparative study shows that high-performance liquid chromatography with fluorimetric detection is a reliable and specific method, but it is relatively slow and sometimes lacks sensitivity. A commercially-available radioimmunoassay kit is convenient, but there is a cross reaction with the major metabolise adriamycinol and unless the assay is combined with an extraction step, it gives erroneously high results.  相似文献   
98.
With the objective of testing the value of neoadjuvant chemotherapy in patients with stage III B carcinoma of the cervix, we began in 1984 a randomized, phase III trial comparing BOMP chemotherapy followed by pelvic radiotherapy versus pelvic radiotherapy alone. Patients were stratified by age, extension of parametrial involvement, and lymphangiographic findings. Despite a higher complete response rate, the overall 5-year survival was significantly inferior in the combined therapy group (39% vs 23%, P=0.02). Toxicity was more pronounced in the chemoradiation arm and 4 patients developed fatal pulmonary complications. Patterns of failure were similar in both groups. The use of primary chemotherapy in advanced carcinoma of the cervix was detrimental to the patients and its use outside a protocol setting is discouraged.  相似文献   
99.
100.
目的:筛选一株优良的抗生素产生菌。方法:通过人为诱变来动摇产生菌原有的严密控制机制。结果:得到一种抗生素生物合成能力异常的突变株。结论:此方法可过量合成人们所期望的抗生素。  相似文献   
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