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991.
Shaw GB 《International journal of epidemiology》2003,32(6):910-5; discussion 915-6
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The paper presents an analysis of the policy advocacy strategies used by both proponents and opponents of needle exchange programs in the US, drawing on the analytic framework developed by Stone. Based on a case study of the politics of needle exchange in Massachusetts, we argue that proponents of needle exchange have relied almost exclusively on empirical scientific arguments to build their case, while opponents have generally resorted to normative ethical arguments. Since the frames of argument are unrelated, the two sides talk past one another, bypassing progress towards resolution or consensus. By failing to address the ethical concerns raised by opponents, public health advocates of needle exchange are losing the larger public debate. The paper concludes with specific recommendations for how public health advocates should respond to the normative dimensions of this public policy issue.  相似文献   
994.
Evidence of Leishmania infection was found in small mammals captured between 1996 and 2000 in the Amaraji region, Pernambuco State, Brazil. The kDNA polymerase chain reaction (PCR), using primers specific for subgenus L. (Viannia), was positive for 43/153 water rats (Nectomys squamipes), 13/81 black rats (Rattus rattus), 15/103 grass mice (Bolomys lasiurus), 1/14 marsh mice (Holochilus scieurus), 2/50 field mice (Akodon arviculoides), 2/12 woolly opossums (Marmosa sp.), and 5/37 common opossums (Didelphis albiventris). This same kDNA PCR was positive for 12/61 dog and 8/58 horse skin samples. In paired PCR tests of 203 small mammals, 18.7% were positive with the kDNA primers and 18.2% with rDNA primers. Amastigotes were seen in 26/460 and L. (V.) braziliensis was isolated from 5 grass mice and 1 black rat. We concluded that small mammals, particularly rodents, are infected with parasites of the subgenus L. (Viannia). The isolation of L. (V.) braziliensis zymodeme IOC/Z74 from 6 rodents and the fact that all the other described L. (Viannia) species that commonly infect humans have never been found in rodents or marsupials leads us to suggest that the positive PCRs indicate infections of L. (V.) braziliensis. The isolation of zymodeme IOC/Z74 from humans reinforces our hypothesis that small, ground-loving mammals, such as rodents are the primary reservoirs of L. (V.) braziliensis.  相似文献   
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Shaw MB  McInerney JJ  Dias JJ  Evans PA 《Injury》2003,34(6):438-442
Acromioclavicular joint (ACJ) sprains occur after injuries to the shoulder girdle. Current practice is to treat such injuries conservatively. This study determines the recovery interval of ACJ sprains treated conservatively. Forty-seven patients with grades I or II ACJ sprains were evaluated in a shoulder clinic and treated conservatively. The average age was 37 years, with the injury being caused by a fall, contact sport or road-traffic accident. At an interval of 12 months or greater these patients were assessed by means of a questionnaire. Six months post-injury, pain was described as significant by 14 (40%) patients, decreasing to 5 patients (14%) at final follow-up. A restricted range of movement was reported by seven patients (20%) 6 months post-injury. There is a positive correlation between patients symptomatic at 6 months and those whose symptoms persist beyond 1 year (r=0.6, 95% CI=0.28-0.76, P<0.01). Three patients (9%) found that symptoms affected their ability to perform activities of daily living and two patients (6%) had to change sporting activities. Patients may continue to experience adverse symptoms beyond 6 months and should be advised accordingly on appropriate treatment should symptoms persist.  相似文献   
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BACKGROUND: The authors evaluated clinical and pathologic factors that predicted for recurrence after patients underwent radical surgery for International Federation of Gynecology and Obstetrics (FIGO) Stage IA(2)-IB(1-2) cervical carcinoma and developed a simple method of scoring those predictive factors to quantify outcome. METHODS: An analysis was conducted of a prospective radical surgery cervical carcinoma data base. A Cox proportional hazards regression analysis was done for each of the individual factors to estimate individual risk ratios using all available data for each factor. Stepwise and best-model options were used to identify the best combinations as predictors and to calculate adjusted risk ratios. Based on the information obtained, each patient was assigned a categorical score to predict recurrence. The variables used for the score were dichotomized. The differences between the scores in time to recurrence were evaluated using the log-rank test to compare the time to recurrence curves that were generated with the Kaplan-Meier method. RESULTS: Eight hundred seventy-one patients were included in the study, and 66 patients who developed recurrent disease after a median follow-up of 49 months. Tumor size, maximum depth of invasion, pelvic lymph node status, tumor grade, and capillary lymphatic space (CLS) were single predictors for recurrence, and the score, which was based on combinations of these factors, predicted the disease free survival. Maximum depth of invasion, pelvic lymph node status, and CLS were the best combined predictors for recurrence, and they were used to form a second, precise scoring system to predict disease free survival (P < 0.0001; log-rank test). CONCLUSIONS: The scoring system based on maximal depth of invasion, CLS, and pelvic lymph node metastases identified four strata of patients with distinct recurrence free survival. The incremental presence of each factor decreased recurrence free survival after patients underwent radical surgery. Patients with the presence of all three factors had a 5-year recurrence free survival rate of 65%. These patients would be suitable for studies of postoperative adjuvant therapy to improve outcome.  相似文献   
1000.
BACKGROUND: Concerns about potential health effects of trihalomethanes (THMs) have prompted investigations on whether infants whose mothers were periconceptionally exposed to drinking water containing THMs are at greater risk of congenital malformations. METHODS: We used two large case-control maternal interview studies that were conducted among California deliveries from 1987 through 1991. One study comprised 538 infants/fetuses with neural tube defects (NTDs) and 539 nonmalformed control infants. The second study included an additional 265 infants with NTDs, 207 infants with conotruncal heart defects, 409 infants with orofacial clefts, and 481 control infants. Expert personnel from municipal water companies estimated THM levels for a particular residence and specific periconceptional time period using quarterly monitoring measurements. Estimates were also made for four individual THM levels and for the total THM level. RESULTS: NTD risk in the first study was inversely associated with total THM exposure. Although the second study did not show the same inverse relationship for NTDs, there were no positive associations of NTDs or the other malformations with total THM as estimated from continuous models. Elevated risks were observed for the lowest category of exposure (1-24 ppb), but risks were either not substantially elevated or were imprecise for higher exposure levels. Thus no evidence was observed for an exposure-response relation. CONCLUSIONS: Our results do not provide a clear pattern of association between THM exposure and risks of specific congenital malformations. Imprecise exposure measures coupled with a lack of information about other possible sources of THM exposure may have caused associations to be underestimated.  相似文献   
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