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51.
Amikacin resistance, rare among nocardiae, was observed in 58 clinical isolates of nocardiae. All of these isolates hydrolyzed hypoxanthine, and 75 to 100% utilized citrate, D-galactose, and D-trehalose as sole carbon sources. Based on utilization of I-erythritol, D-glucitol, i-myo-inositol, D-mannitol, and ribitol and susceptibility to amoxicillin-clavulanic acid, the 58 isolates were separable into four groups. One group was negative for I-erythritol and ribitol and included all the isolates belonging to Nocardia asteroides complex antibiogram type IV. The remaining three groups were positive for I-erythritol and ribitol and were grouped within Nocardia transvalensis. The group that included the type strain was designated N. transvalensis sensu stricto, and the other two groups were designated new taxons 1 and 2. PCR-restriction fragment length polymorphism (RFLP) analysis of a 439-bp segment of the 65-kDa heat shock protein gene with XhoI and HinfI produced identical patterns for 53 (91%) and 58 (100%) isolates, respectively, and differentiated them from all other Nocardia taxa. NarI- and HaeIII-derived RFLP patterns clearly differentiated each of the four biochemically defined taxa. These four groups were also distinguishable by using the chromogenic substrates in Dade MicroScan test panels. By high-performance liquid chromatography, these isolates exhibited the same unique mycolic acid-ester elution patterns that differed from those of all other clinically significant nocardiae. Gas-liquid chromatographic analysis of fatty acids also produced similar patterns for all isolates that distinguished them from all other Nocardia taxa, but did not differentiate the four taxa within the complex. We propose the designation N. transvalensis complex for these four groups of nocardiae, pending further genetic evaluation.  相似文献   
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OBJECTIVES: To describe health risk behavior, knowledge, and attitudes about HIV/AIDS and its prevention in men who have sex with men (MSM) in Ho Chi Minh City (HCMC), Vietnam. METHODS: A cross-sectional survey of 219 MSM using a standardized questionnaire. RESULTS: Men who have sex with men were easy to locate and willing to answer detailed questions about their sexual behavior. Self-identified sexual orientation was 67% homosexual, 31% bisexual, and 1.4% heterosexual. High-risk sexual behavior was common. The mean number of sexual partners was 3.3 in the previous month and 14.8 in the previous year. Only 32% used condoms during their last intercourse, and only 40% used a condom when their last intercourse included anal sex. Eighty-one percent reported sex with nonregular male partners, and 22% also had sex with women in the past year. Drug use other than alcohol was rare. Most correctly identified high-risk sexual behavior and body fluids that could transmit HIV; however, only about half knew that someone who appeared healthy could transmit HIV or that there was no cure for AIDS. Self-rated risk for HIV was very low, and fewer than one third believed that homosexuals in Vietnam are at increased risk for HIV. CONCLUSION: Men who have sex with men in HCMC are at high risk for HIV. Knowledge about HIV transmission and prevention could be improved. Education and interventions specifically aimed at MSM are needed, because education targeted at the general population may not reach MSM or influence their behavior.  相似文献   
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SettingThis knowledge mobilization project was conceptualized to increase awareness among breastfeeding mothers and the general public on safe infant feeding practices during the COVID-19 pandemic by addressing myths and misconceptions associated with breastfeeding practices, guiding breastfeeding mothers to make informed decisions around child feeding practices, and offering meaningful guidance in simple language through a short online animated video.InterventionThis project was undertaken in four phases. During phase 1, an informal discussion was held with the breastfeeding mothers, service providers, and community partner in identifying issues surrounding lactation counselling facilities during the COVID-19 pandemic. During phase 2, recommendations from 23 organizations with regard to breastfeeding during COVID-19 were reviewed and analyzed. During phase 3, using evidence from reliable sources, a 5-minute animated e-resource on breastfeeding during COVID-19 was conceptualized and developed. During phase 4, the e-resource was disseminated to the breastfeeding mothers, general public, post-secondary institutions, and organizations providing services to breastfeeding mothers in Canada.OutcomesThis evidence-based e-resource facilitated addressing misconceptions around breastfeeding during COVID-19 and raising public awareness on safe infant feeding practices during this pandemic. Overall, the video was described as an informative, user-friendly, useful, and easily accessible resource by breastfeeding mothers who were in self-isolation with little access to healthcare services during the pandemic.ImplicationsThis project highlighted the importance of patient engagement and collaboration with the community partner in protecting breastfeeding during the COVID-19 pandemic. It further illustrated how informational e-resources can protect breastfeeding in situations where breastfeeding mothers’ access to healthcare services is compromised.  相似文献   
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Multifocal intraocular lenses   总被引:2,自引:0,他引:2  
It has been 10 years since I implanted the first multifocal intraocular lens (IOL). Unfortunately, there has been a gradual lessening of commitment to this modality by the ophthalmic community. The most important single factor for this lack of interest despite the more than adequate available clinical data is the repeated moving of "goal posts" by the American FDA when a multifocal lens style nears premarket approval. The refractive multifocal lens styles of iolab (Claremont, CA), Stortz Ophthalmics (St. Louis, MO), Domilens (Lyon, France), and Amo with the diffractive multifocals of 3M (St. Louis, MO), and Pharmacia (Kalamazoo, MI) and their recent modifications are reviewed. Reports show that they generally give excellent visual results depending on whether a near or distance dominant lens is indicated. The foldable Amo Array SA40N provides a good distance dominant foldable lens for the surgeon performing small incisions and has a small but dedicated surgical following. Loss of contrast sensitivity at low-light levels remains a source of concern in certain professions and with certain lifestyles, and a report suggesting that many monofocal and multifocal patients do not achieve the standards set for night driving by the German Ophthalmic Society warrants further consideration. Development of a new accommodative IOL for small incision surgery is the only really new concept, and it will be interesting to see the results of independent reports. Spectacle dependence is considerably reduced with all the current multifocals when compared to monofocals, and for patients there are ample multifocal lens styles from which to choose. It is the author's opinion that more than 60% of the cataract population is currently suitable for multifocals if small incision surgery is performed. More multifocals would be used if price disparity with monofocals was reduced.  相似文献   
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A case is presented of a healthy 69-yr-old woman who underwent elective laparoscopic cholecystectomy under general anaesthesia. As surgery proceeded she developed hypercapnia (arterial blood PaCO2 = 100 mmHg) and a related respiratory acidosis (arterial blood pH 7.07). The cause was attributed to subcutaneous insufflation and absorption of CO2, directly related to the surgical pneumoperitoneum.  相似文献   
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OBJECTIVE: The authors review their recent experience with resected pancreatic ductal adenocarcinoma. SUMMARY BACKGROUND DATA: Ductal adenocarcinoma of the pancreas has traditionally had a 5-year survival rate less than 10% after curative resection. Recently, several groups have reported markedly improved 5-year survival rates (approaching 25%) for patients undergoing curative resection. METHODS: Institutional experience with 186 consecutive patients (1981-1991) with pathologic diagnoses of ductal adenocarcinoma undergoing pancreatic resection was reviewed. Histologic specimens of all 3-year survivors (n = 31) were re-reviewed by two pathologists, one internal and one external; nonductal pancreatic cancers then were excluded. RESULTS: After histologic re-review, 12 patients did not have ductal adenocarcinoma, leaving a total of 174 patients for analysis (102 men, 72 women; mean age 63 years, range 34-82 years). Mean follow-up was 22 months (range 4-109). Classical pancreaticoduodenectomy was performed in 71%, pylorus-preserving resection in 9%, and total pancreatectomy in 20%. Hospital mortality was 3%. Twenty-eight patients (16%) had macroscopically incomplete resections; 98 (56%) had lymph node metastases within the resected specimens, and 21 patients (12%) had extensive perineural invasion. Overall actuarial 5-year survival was 6.8%. Five-year survival was greater for node-negative versus node-positive patients (14% vs. 1%, p < 0.001), and for smaller (< 2 cm) versus larger tumors (20% vs. 1%, p < 0.001). The 5-year survival for the subset of patients with negative nodes and no perineural or duodenal invasion (69 patients) was 23% (p < 0.001). Mean survival of the 12 excluded patients was 53 +/- 7 months compared with 17.5 +/- 1 months in the 174 patients with ductal pancreatic cancer. CONCLUSIONS: Five-year survival for patients undergoing pancreatic resection for lesions deemed to be clinically "curable" intraoperatively and histologically reviewed/confirmed to be ductal adenocarcinoma of the pancreas is approximately 7%. Survival is greater (23%) in the subset of patients with negative nodes and no duodenal or perineural invasions. Pathologic review of all patients with pancreatic ductal cancer adenocarcinoma is mandatory if survival data are to be meaningful.  相似文献   
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