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991.
Rationale The prevention of human immunodeficiency virus/sexually transmitted diseases remains a significant global public health issue, especially among vulnerable populations. Aims and objectives To promote condom use skills among young urban African American men. Methods As a pilot study, a randomized controlled trial was conducted among 136 African American men aged 18–24 years recruited from urban communities in Chicago. Participants assigned to the intervention received 45–60 minutes of a one‐on‐one single‐session condom promotion program delivered by trained facilitators while those assigned to the attention‐matched comparison condition received a general health program. Longitudinally, 115 (85%) and 120 (88%) participants completed the 3‐month and 6‐month follow‐up surveys, respectively. Results Overall, the study results indicate that positive effects were observed from baseline to 6‐month follow‐up for intervention participants relative to comparison condition participants for prior condom use (1.23–1.82 versus 1.34–0.97); condom use intention (2.51–3.19 versus 2.69–2.21); perceived condom availability (3.44–3.72 versus 3.42–3.38); positive reasons to use condoms (2.82–3.08 versus 2.95–1.99); favourable condom use attitude (2.41–2.69 versus 2.49–1.95); barriers to condom use (1.33–0.79 versus 1.25–1.85); and negative condom use attitude (1.45–0.66 versus 1.33–1.39), respectively. Conclusions We conclude that a brief single‐session condom promotion program is effective in preventing high‐risk sexual behaviours among urban young adult African American men.  相似文献   
992.
SUMMARY We have reviewed 39 adult patients who presented over a 5-year period with biopsy confirmed renal disease in association with positive antineutrophil cytoplasmic antibody (18 with C-ANCA, 21 with P-ANCA). Twenty-three (59%) had primary systemic vasculitis, typically with aggressive renal histology including focal necrotising and crescentic glomerulonephritis. In the remaining patients a wide range of clinical syndromes and renal histological appearances were apparent: 30 had abnormal renal function (serum creatinine >140 μmol/l), including 17 who were initially dialysis-dependent. Intensive immunosuppression was administered in 33 cases. When response was assessed at 3 months, renal function was stable or improved in 17 (52%), 5 of whom were able to discontinue dialysis. There was, however, an appreciable early mortality and, at latest follow-up (1–57 months), 12 patients had died and 8 were on the dialysis programme. On immunosuppression, ANCA became negative in the majority (median time 1.5 months) but recurred during clinical relapse in 11 cases. In asymptomatic patients (12 cases), the reappearance of ANCA positivity did not herald clinical relapse. The ANCA assay has increased awareness of systemic vasculitis but not removed the need for histological confirmation before instituting immunosuppression.  相似文献   
993.
994.

Background and objective

The blocking of aldosterone or angiotensin II receptors improves mortality in patients with chronic heart failure. We explored whether combining losartan and spironolactone would have any added benefit on the known surrogate of mortality by using heart rate variability (HRV) and QT dispersion as our endpoints.

Methods

We designed a three-phase, consecutive, randomised, controlled, double-blind, cross-over pilot study to assess the effects of losartan alone (50 mg/day), spironolactone (25 mg/day) with angiotensin converting enzyme (ACE) inhibitor and, finally, losartan with spironolactone, on HRV and QT dispersion. We enrolled eight patients (aged 47 to 72 years, mean = 63.7 years), with New York Heart Association (NYHA) class II–III heart failure and ejection fraction (EF) < 35%, in the study at a university-affiliated hospital in Dundee, Scotland. Digital 24-hour Holter recordings were analysed for time-domain HRV and the 12-lead ECG was optically scanned and digitised for analysis of QT dispersion. Evaluations were done at baseline, and at six, 12 and 18 weeks from baseline.

Results

Losartan and spironolactone showed statistically significant, favourable effects on HRV, QT dispersion and mean heart rate (p < 0.05).

Conclusion

The data showed that in these patients with heart failure, the addition of spironolactone to an ACE inhibitor, or the use of losartan on its own, or the combination of losartan plus spironolactone induced a favourable sympathovagal balance. The drugs significantly improved HRV indices and QT dispersion further, and the combination appeared to be safe. However, no significant differences were seen between the effects of each of these regimes on HRV and QT dispersion.  相似文献   
995.
ObjectiveTo evaluate the values of some major hematological parameters at different trimesters of pregnancy.MethodsThe research involved 33 healthy pregnant women as the study group and 11 non-pregnant women as control. The age range of these women was 20-40 years. Ethical approval was obtained from Olabisi Onabanjo University Teaching Hospital, Sagamu. Three milliliters of venous blood collected from the median cubital vein with minimum stasis were put into K+EDTA bottle. The blood was properly mixed and analyzed for packed cell volume (PCV), total white cell count, differential counts and erythrocyte sedimentation rate (ESR). Hematology was done according to standard methods.ResultsThe result showed that study group exhibited statistically significant lower values of PCV, monocyte and lymphocyte while WBC, eosinophil and ESR were not significantly changed. There was no significant difference in all hematological parameters among the three trimesters.ConclusionsHealthy pregnancy may have effect on hematological parameters. Therefore, there is a need to monitor these parameters during pregnancy. We also find that stages of pregnancy have no influence on hematological parameters.  相似文献   
996.

Background

The lungs are involved in up to 70% of cases of leptospirosis. In the more severe forms-bleeding from the lungs and acute respiratory distress syndrome-the lethality is high. The treatment proposed for leptospirotic pneumonitis includes just care for patients in critical condition. Clinical and experimental studies point to the involvement of immunological mechanisms in the physiopathology of lung damage caused by leptospirosis. The aim of this study is to evaluate pulse treatment with methylprednisolone × placebo for leptospirotic pneumonitis.

Study design

This is a randomized double-blind clinical trial to test the efficacy of pulse treatment with methylprednisolone in patients with leptospirotic pneumonitis, compared with a placebo. The patients are recruited from three hospitals in the city of Recife, in the Brazilian State of Pernambuco. The exclusion criteria include patients aged under 15 years, a history of hypersensitivity to the use of corticosteroids, the presence of active infection of fungal, tuberculous or bacterial origin apart from the infection by leptospira itself, the presence of hemoconcentration or atypical lymphocyte count on admission to hospital, the presence of co-morbidities that could be responsible for the radiological and gasometric alterations used to diagnose leptospirotic pneumonitis, evidence of recent cranial trauma, neurosurgery, peptic ulcer, and participation in another clinical trial. The patients are followed until they are discharged from hospital or die. The intervention consists of endovenous pulse treatment with 1 g methylprednisolone for three consecutive days in the study group and a placebo in the control group. The primary end-point is mortality from leptospirotic pneumonitis. The secondary end-points are: evolution of lung disease; the occurrence of nosocomial respiratory infection; duration of mechanical ventilation; duration of intensive care unit (ICU) stay; duration of hospital stay; occurrence of other infection-related complications; other respiratory complications; and adverse effects of methylprednisolone. The study is designed to recruit 266 patients and has a statistical "power" of 80% to detect a 50% reduction in mortality.

Discussion

Lung involvement in leptospirosis is a serious manifestation, with a high and variable mortality rate. There is still no specific clearly-established treatment. Well-designed studies are needed to pave the way towards development of such a treatment.
  相似文献   
997.
998.
999.
The chemokines are a family of signalling proteins that participate in regulation of the immune system and have been implicated in the pathogenesis of vascular diseases. Deleting the gene encoding the chemokine MCP-1 in mouse models of atherosclerosis reduces lipid lesion formation and circulating chemokines are upregulated in man immediately following myocardial infarction (MI) or coronary angioplasty. We have therefore investigated whether circulating levels of two chemokines (MCP-1 and eotaxin) differ between subjects with and without atherosclerosis. We have used three different methods of measuring the presence and extent of atherosclerosis in human subjects: duplex ultrasonography of the carotid arteries and clinical diagnosis of coronary heart disease on individuals from the general population and coronary angiography on patients with suspected heart disease. There was no difference in the levels of circulating MCP-1 or eotaxin, measured by ELISA, between subjects with and without atherosclerosis. Furthermore, any increase in circulating MCP-1 following acute MI must be short-lived, since chemokine levels were not different in subjects who had had an MI previously compared to those who had not. We conclude that although there may be a transient increase in circulating chemokine levels following coronary angioplasty, there is no difference in the levels of circulating MCP-1 or eotaxin in subjects with and without atherosclerosis.  相似文献   
1000.
The objectives were to determine the efficacy and safety of nasal salmon calcitonin 200 IU daily in the prevention of corticosteroid- induced osteoporosis. A minimized, double-blind, placebo-controlled trial was carried out in corticosteroid-treated patients with polymyalgia rheumatica. The setting was a tertiary care university- affiliated hospital and a total of 31 patients were enrolled. The primary outcome measure was the percentage change in bone mineral density of the lumbar spine in the two treatment groups from baseline to 1 yr of follow-up. The mean +/- S.D. bone mineral density of the lumbar spine in the calcitonin-treated group decreased by 1.29 +/- 6.76% and in the placebo group by 4.95 +/- 3.50% after 12 months. The observed difference of 3.65 +/- 2.10% between groups is statistically significant (P < 0.05). Nasal salmon calcitonin prevented loss of bone in the lumbar spine as measured by dual-energy X-ray absorptiometry.   相似文献   
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