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51.
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Background

Verbal autopsy (VA) has often been used for point estimates of cause-specific mortality, but seldom to characterize long-term changes in epidemic patterns. Monitoring emerging causes of death involves practitioners' developing perceptions of diseases and demands consistent methods and practices. Here we retrospectively analyze HIV-related mortality in South Africa, using physician and modeled interpretation.

Methods

Between 1992 and 2005, 94% of 6,153 deaths which occurred in the Agincourt subdistrict had VAs completed, and coded by two physicians and the InterVA model. The physician causes of death were consolidated into a single consensus underlying cause per case, with an additional physician arbitrating where different diagnoses persisted. HIV-related mortality rates and proportions of deaths coded as HIV-related by individual physicians, physician consensus, and the InterVA model were compared over time.

Results

Approximately 20% of deaths were HIV-related, ranging from early low levels to tenfold-higher later population rates (2.5 per 1,000 person-years). Rates were higher among children under 5 years and adults 20 to 64 years. Adult mortality shifted to older ages as the epidemic progressed, with a noticeable number of HIV-related deaths in the over-65 year age group latterly. Early InterVA results suggested slightly higher initial HIV-related mortality than physician consensus found. Overall, physician consensus and InterVA results characterized the epidemic very similarly. Individual physicians showed marked interobserver variation, with consensus findings generally reflecting slightly lower proportions of HIV-related deaths. Aggregated findings for first versus second physician did not differ appreciably.

Conclusions

VA effectively detected a very significant epidemic of HIV-related mortality. Using either physicians or InterVA gave closely comparable findings regarding the epidemic. The consistency between two physician coders per case (from a pool of 14) suggests that double coding may be unnecessary, although the consensus rate of HIV-related mortality was approximately 8% lower than by individual physicians. Consistency within and between individual physicians, individual perceptions of epidemic dynamics, and the inherent consistency of models are important considerations here. The ability of the InterVA model to track a more than tenfold increase in HIV-related mortality over time suggests that finely tuned "local" versions of models for VA interpretation are not necessary.  相似文献   
53.

Background

Little focus has been paid to the role of mental health among young people with regard to risky sexual behavior and HIV prevention in sub-Saharan Africa. The aim of this study was to investigate the relationship between poor mental health and risky sexual behavior (HIV/AIDS) among a population of university students in Uganda.

Methods

In 2005, 980 Ugandan university students completed a self-administered questionnaire (response rate 80%) assessing sociodemographic and religious background factors, mental health, alcohol use, and sexual behavior. Mental health was assessed using items from the Hopkins Symptoms Checklist-25 and the Symptom Checklist-90.

Results

High scores on depression and high numbers of sexual partners among both males (odds ratio (OR) 2.0, 95% confidence interval (CI) 1.2?C3.3) and females (OR 3.3, 95% CI 1.3?C8.6) were significantly associated. Elevated anxiety scores among men were associated with high numbers of sexual partners (OR 1.9, 95% CI 1.1?C3.3) and inconsistent condom use (OR 1.9, 95% CI 1.1?C3.6). Psychoticism was also significantly associated with high numbers of sexual partners among men. The associations remained statistically significant after controlling for sociodemographic factors and level of alcohol consumption.

Conclusion

These findings indicate that previous conclusions on the association between sexual behavior and mental health from high- and middle-income countries also are valid in a low-income setting, such as in Uganda. This knowledge has implications for policy formation and HIV/AIDS preventive strategies. Coordinated youth-friendly mental health and sexual and reproductive health services to meet the needs of young people would be desirable.  相似文献   
54.
Sixty-five multiply transfused patients with severe aplastic anemia were given cyclophosphamide followed by grafts anemia were given cyclophosphamide followed by grafts from HLA-identical siblings. The effect of the administration of viable donor buffy coat cells following the marrow inoculum was evaluated with regard to graft rejection and survival. Results in 43 patients so treated are presented along with those in 22 concurrent patients given marrow alone. Most patients given buffy coat had positive in vitro tests of sensitization indicating a high risk for graft rejection, while all but one of the patients given marrow alone had negative tests. Thirty of the 43 (70%) patients given marrow and buffy coat are alive between 10 and 61 mo (median 36) after grafting; 4 died after graft rejection and 6 with acute or chronic graft-versus-host disease (GVHD). Eleven of the 22 (50%) patients given marrow alone are alive between 29 and 65 mo (median 52); 7 died after graft rejection and 3 with GVHD. The addition of buffy coat cell infusions to the marrow inoculum reduced the risk of rejection and increased survival in the currently reported transfused patients when compared to patients grafted before 1976. However, there was an increased risk of chronic GVHD. Recipients of marrow from female donors survived slightly better (73%) than recipients of male marrow (58%).  相似文献   
55.
A prospective randomized study was conducted comparing two conditioning regimens for the treatment of patients with chronic myeloid leukemia in chronic phase by marrow transplantation from HLA identical siblings. Sixty-nine patients received 60 mg/kg of cyclophosphamide on each of 2 successive days followed by 6 fractions of total body irradiation each of 2.0 Gy (CY-TBI), and 73 patients received 16 mg/kg of busulfan delivered over 4 days followed by 60 mg/kg CY on each of 2 successive days (BU-CY). There was no significant difference between the CY-TBI and the BU-CY groups in the 3-year probabilities of survival (0.80 for both), relapse (0.13 for both), or event-free survival (CY-TBI, 0.68; BU-CY, 0.71) or in speed of engraftment or incidence of venocclusive disease of the liver. The 4-year probabilities of survival and event- free survival for patients transplanted within 1 year of diagnosis were 0.86 and 0.72, respectively, for each group. Significantly more patients in the CY-TBI group experienced major creatinine elevations. There was significantly more acute graft-versus-host disease in the CY- TBI group. Fever days, positive blood cultures, hospitalizations, and inpatient hospital days were significantly more common in the CY-TBI group than in the BU-CY group. In conclusion, the BU-CY regimen was better tolerated than, and associated with survival and relapse probabilities that compare favorably with, the CY-TBI regimen.  相似文献   
56.
Chou  AC; Broun  GO Jr; Fitch  CD 《Blood》1978,52(1):187-195
Rabbits fed a vitamin E-deficient diet developed severe muscular dystrophy in 3-4 wk, but they did not become anemic. Nevertheless, reticulocyte counts increased in deficient rabbits (3.2%) compared to control rabbits (0.9%), and erythroid hyperplasia was evident in the bone marrow. Comparing deficient rabbits to controls, the plasma iron concentration was lower (134.4 versus 206.6 microgram/dl); the TIBC was higher (335.9 versus 228.3 microgram/dl); the whole blood protoporphyrin concentration was higher (131.6 versus 81.7 microgram/dl); and the total iron content was lower in spleen (71 versus 153 microgram), higher in skeletal muscle (4956 versus 3054 microgram), and unchanged in bone marrow, liver, and heart. Studies of iron absorption and excretion using 59Fe showed no abnormalities in deficient rabbits. There were abnormalities of ferrokinetics, however. The half-time of disappearance of 59Fe was shorter (100.6 versus 169.4 min), the plasma iron turnover was greater (1.25 versus 0.95 mg/dl blood/day), and the reappearance of 59Fe in circulating erythrocytes at day 9 was greater (77.2% versus 57.2%) in deficient rabbits. Anemia induced by phlebotomy accentuated the abnormal iron metabolism of deficient rabbits, and the animals were unable to correct the anemia. These findings show that vitamin E deficiency in rabbits causes abnormal erythropoiesis associated with abnormal iron metabolism and sequestration of iron in skeletal muscle.  相似文献   
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