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OBJECTIVE: To describe investigation of a tightly clustered outbreak of invasive group A streptococcal (GAS) disease associated with a high mortality rate in a long-term care facility (LTCF). DESIGN: Cross-sectional carriage survey and epidemiologic investigation of LTCF resident and employee cohorts. SETTING: A 104-bed community LTCF between March 1 and April 7, 2004. PATIENTS: A cohort of LTCF residents with assigned beds at the time of the outbreak. INTERVENTIONS: Reinforcement of standard infection control measures and receipt of chemoprophylaxis by GAS carriers. RESULTS: Four confirmed and 2 probable GAS cases occurred between March 16 and April 1, 2004. Four case patients died. The final case occurred during the investigation, before the patient was determined to be a GAS carrier. No case occurred during the 6 months after the intervention. Disease was caused by type emm3 GAS; 16.5% of residents and 2.4% of employees carried the outbreak strain. Disease was clustered in 1 quadrant of the LTCF and associated with nonintact skin. GAS disease or carriage was associated with having frequent personal visitors. CONCLUSIONS: Widespread carriage of a virulent GAS strain likely resulted from inadequate infection control measures. Enhanced infection control and targeted prophylaxis for GAS carriers appeared to end the outbreak. In addition to employees, regular visitors to LTCFs should be trained in hand hygiene and infection control because of the potential for extended relationships over time, leading to interaction with multiple residents, and disease transmission in such residential settings. Specific attention to prevention of skin breaks and proper wound care may prevent disease. The occurrence of a sixth case during the investigation suggests urgency in addressing severe, large, or tightly clustered outbreaks of GAS infection in LTCFs.  相似文献   
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PURPOSE: We systematically assessed the efficacy and safety of appetite stimulants in the management of cancer-related anorexia. Literature databases were searched for randomized controlled trials of appetite stimulants in the treatment of cancer anorexia. MATERIALS AND METHODS: Studies were graded according to quality. Fifty-five studies met inclusion criteria. RESULTS: Only two drugs have evidence to support their use for anorexia (progestins and corticosteroids). There is strong evidence against the use of hydrazine sulfate. The outcomes of these trials have been mixed and patient population heterogeneous. CONCLUSION: The optimal dose, time to start, and duration of treatment for many appetite stimulants for cancer anorexia is still unknown. A more systematic approach to research methodology with universal outcome measure and prospective randomized studies are need. Combination regimens are needed but this cannot at the present time be supported by the data presented.  相似文献   
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BACKGROUND: Improvement in aerobic capacity and reduction in blood pressure after Tai Chi exercise programs in persons with coronary heart disease (CHD) or with CHD risk factors have been reported. Self-efficacy has been shown to be a consistent predictor of behavioral outcomes, now being applied to Tai Chi exercise. AIM: To assess the utility and appropriateness of existing tools measuring aspects of Tai Chi exercise self-efficacy (TCSE) in a new population, ethnic Chinese with CHD risk factors. Specific objectives were: (1) examine acceptability and feasibility; (2) determine score distributions; (3) assess the reliability and known-groups validity; (4) translate tool into an equivalent Chinese version and determine if there were any differences between ethnic Chinese and non-Chinese. METHODS: Following a review of the literature, two existing tools used with Caucasians were found and modified; a 9-item exercise self-efficacy tool developed by Resnick and Jenkins [Resnick B, Jenkins LS, Testing the reliability and validity of the Self-Efficacy for Exercise scale. Nurs. Res. 49(3) (2000) 154-159], and a 3-item tool developed by Li et al. [Li F, McAuley E, Harmer P, Duncan TE, Chaumeton NR, Tai Chi enhances self-efficacy and exercise behavior in older adults. J. Aging Phys. Act. 9 (2001) 161-171] to assess gradations of the challenge to perform Tai Chi among elderly populations. The modified TCSE tool was translated into Chinese and back-translated. A pilot study was conducted to pre-test the modified 14-item TCSE tool in ethnic Chinese and non-Chinese. RESULTS: A total of 18 subjects (mean age = 60 years, S.D. = 18.4) participated. Seven subjects (39%) identified themselves as ethnic Chinese. Ten subjects (56%) had experience performing Tai Chi, ranging from 3 months to 17 years (mean = 5.0 years, S.D.=5.0). Half of the subjects reported having a history of hypertension (n = 9, 50%), while nearly one-third reported having high cholesterol (n = 5, 28%). No significant difference in TCSE mean scores was found between ethnic Chinese and non-Chinese (p > 0.05). Internal consistency estimates were very high (TCSE Barriers, r = 0.95; TCSE Performance, r = 0.97). A statistically significant difference was found in the TCSE mean scores between Tai Chi practitioners and non-practitioners (TCSE Barriers, t = -3.3, p = 0.01; TCSE Performance, t = -2.7, p = 0.03), with Tai Chi practitioners reporting higher self-efficacy; thus providing initial evidence of known-groups validity. CONCLUSIONS: Measurement of self-efficacy to overcome barriers to Tai Chi exercise (TCSE Barriers) and self-efficacy to perform Tai Chi (TCSE Performance) functioned well in this sample. The acceptability and feasibility of this tool was established and known-groups validity was confirmed. Further research using this tool among ethnic Chinese with CHD or CHD risk factors, including those with less than high school education or low literacy, is recommended as the next step in development of TCSE.  相似文献   
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Background.This study prospectively examined rates of adherence to mammography, clinical breast examination (CBE), and breast self-examination (BSE) in a cohort of women over 3 years to determine whether participation in BSE influenced participation in the other two screening modalities.Methods.Women ages 51 and older (n= 450) who attended a small group educational session to learn BSE and to hear about CBE and mammography guidelines were assessed annually by telephone for 3 consecutive years to determine their subsequent breast cancer screening behavior.Results.Annual CBE and mammography screening are highly positively associated. Regular performance of BSE has a modest positive association with both CBE and mammography adherence over time.Conclusions.Women who perform BSE regularly over time may be more likely to adhere to the other breast cancer screening guidelines.  相似文献   
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1. The nitric oxide (NO)-releasing properties of two new mesoionic 3-aryl substituted oxatriazole-5-imine derivatives (GEA 3162 and GEA 3175) were characterized and compared with the known NO-donors 3-morpholino-sydnonimine (SIN-1) and S-nitroso-N-acetylpenicillamine (SNAP). 2. GEA 3162, GEA 3175, SIN-1 and SNAP inhibited adenosine 5'-diphosphate-induced platelet aggregation (IC50 values 0.18, 0.39, 3.73 and 2.12 microM, respectively). All four compounds induced a dose-dependent and more than 4 fold increase in cyclic GMP in platelets. The increase in cyclic GMP concentration was potentiated more than 1.5 fold by a phosphodiesterase inhibitor, zaprinast (10 microM) and inhibited 38-97% by oxyhaemoglobin (10-45 microM). 3. All of the four compounds studied converted oxyhaemoglobin to methaemoglobin and formed a paramagnetic NO-haemoglobin complex. All but GEA 3175 formed nitrite and nitrate in phosphate buffer. During a 40 min incubation, GEA 3162, SIN-1 and SNAP (100 microM) produced 50-70 microM NO2- + NO3- as determined by high performance liquid chromatography. The release of NO and NO2 by GEA 3175 was increased 140 fold in the presence of human plasma (0.14 and 19.7 ppb in the absence and presence of 1% human plasma, respectively) as analyzed by ozone chemiluminescence. 4. The results suggest that the mesoionic 3-aryl substituted oxatriazole-5-imine derivatives GEA 3162 and GEA 3175 as well as SIN-1 and SNAP release nitric oxide.  相似文献   
40.
Fungal infections still represent a serious complication after organ transplantation. Early diagnosis and aggressive treatment are crucial. Because of the many diagnostic problems involved, we present a case of mucormycosis--primarily affecting the paranasal sinuses with later intracranial extension--in a highly immunized recipient of a third renal transplant. Although fungal infection was suspected from various imaging techniques, only the detection of typical fungal hyphae in the infected tissue was diagnostic. Neither the blood tests and cerebrospinal fluid examinations performed nor cultures from maxillary sinus fluid were of any diagnostic help. Surgical debridement from a transnasal as well as an intracranial approach and systemic amphotericin B together with the discontinuation of immunosuppression after removal of the rejected graft were able to save the patient. This case stresses the importance of early diagnosis that can only be made from tissue biopsies and allows appropriate timely treatment.  相似文献   
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