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71.
We report an unusual case of localized congenital tuberculosis otitis in a preterm infant. Unlike disseminated congenital cases, the manifestations of localized otitis are associated with a triad of signs: (i) regional lymphadenopathy in the absence of typical systemic features of tuberculosis; (ii) delayed onset of presentation; and (iii) refractory otitis unresponsive to conventional antimicrobial agents. The need for greater diligence in looking for neonatal tuberculosis is emphasized, especially in an ethnic or socioeconomic environment where the disease is prevalent. Congenital tuberculosis, otitis, preterm
PC Ng, Department of Paediatrics, Level 6, Clinical Sciences Building, Prince of Wales Hospital, Shatin, NT, Hong Kong  相似文献   
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73.
BACKGROUND: Antibiotics are frequently prescribed for older adults who reside in long-term care facilities. A substantial proportion of antibiotic use in this setting is inappropriate. Antibiotics are often prescribed for asymptomatic bacteriuria, a condition for which randomized trials of antibiotic therapy indicate no benefit and in fact harm. This proposal describes a randomized trial of diagnostic and therapeutic algorithms to reduce the use of antibiotics in residents of long-term care facilities. METHODS: In this on-going study, 22 nursing homes have been randomized to either use of algorithms (11 nursing homes) or to usual practise (11 nursing homes). The algorithms describe signs and symptoms for which it would be appropriate to send urine cultures or to prescribe antibiotics. The algorithms are introduced by inservicing nursing staff and by conducting one-on-one sessions for physicians using case-scenarios. The primary outcome of the study is courses of antibiotics per 1000 resident days. Secondary outcomes include urine cultures sent and antibiotic courses for urinary indications. Focus groups and semi-structured interviews with key informants will be used to assess the process of implementation and to identify key factors for sustainability.  相似文献   
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75.
OBJECTIVES: We investigated history of abuse and other HIV-related risk factors in a community sample of 490 HIV-positive and HIV-negative African American, European American, and Latina women. METHODS: Baseline interviews were analyzed, and logistic regressions were used to identify predictors of risk for positive HIV serostatus overall and by racial/ethnic group. RESULTS: Race/ethnicity was not an independent predictor of HIV-related risk, and few racial/ethnic differences in risk factors for HIV were seen. Regardless of race/ethnicity, HIV-positive women had more sexual partners, more sexually transmitted diseases, and more severe histories of abuse than did HIV-negative women. Trauma history was a general risk factor for women, irrespective of race/ethnicity. CONCLUSIONS: Limited material resources, exposure to violence, and high-risk sexual behaviors were the best predictors of HIV risk.  相似文献   
76.
To reach the biological alterations that characterize cancer, the genome of tumor cells must acquire increased mutability resulting from a malfunction of a network of genome stability systems, e.g., cell cycle arrest, DNA repair, and high accuracy of DNA synthesis during DNA replication. Numeric chromosomal imbalance, referred to as aneuploidy, is the most prevalent genetic changes recorded among many types of solid tumors. We report here that ectopic expression in cells of DNA polymerase beta, an error-prone enzyme frequently over-regulated in human tumors, induces aneuploidy, an abnormal localization of the centrosome-associated gamma-tubulin protein during mitosis, a deficient mitotic checkpoint, and promotes tumorigenesis in nude immunodeficient mice. Thus, we find that alteration of polymerase beta expression appears to induce major genetic changes associated with a malignant phenotype.  相似文献   
77.

Background  

Efficient delivery strategies for health interventions are essential for high and sustainable coverage. We report impact of a change in programmatic delivery strategy from routine delivery through the Expanded Programme on Immunization (EPI+) approach to twice-yearly mass distribution campaigns on coverage of vitamin A supplementation in Tanzania  相似文献   
78.
Are the words reflex and voluntary useful scientific concepts, or are they prescientific terms that should be discarded? Physiologists use these words routinely in their publications, in laboratory experiments and, indeed, like most lay people, in their daily lives. The tacit assumption is that we all know, more or less, what they mean. However, the issue has a rich history of philosophical and scientific debate; and, as this article demonstrates, present-day researchers still cannot reach a consensus on the meaning of the words and on whether it is possible to draw a scientific distinction between them. The five authors present five quite different analyses. In broad terms, they split into two camps: those who equate voluntary behaviours with consciousness and suppressibility and those who view all behaviours as sensorimotor interactions, the complexity of which determines whether they are reflexive or voluntary. According to the first view, most movements of daily life are neither purely reflex nor purely voluntary. They fall into the middle ground of automatic motor programs. According to the second view, as neuroscience advances the class of reflex behaviours will grow and the class of voluntary behaviours will shrink.  相似文献   
79.
Ataxia-telangiectasia (AT) is an uncommon genetic disorder characterized by cerebellar ataxia, oculocutaneous telangiectasias, progressive immunodeficiency, and a predisposition to lymphoid malignancy. The genetic defect in AT predisposes not only to malignancy but also to severe toxicity from anti-neoplastic therapies. It is important to consider the diagnosis of AT in any child with a lymphoid malignancy at a younger than expected age, or who has a pre-existing ataxia, to anticipate unusually severe toxicities from the antineoplastic therapy, to avoid confusing the development of ataxia with toxicity from therapy, and to provide appropriate genetic counseling. We describe two children at a young age with a lymphoid malignancy diagnosed before the diagnosis of AT. One patient had severe toxicity from his chemotherapy, requiring truncation of the planned course of treatment. The other child was able to tolerate his entire planned course of therapy, but ataxia that was initially interpreted as toxicity from chemotherapy rather than as a sign of his AT developed. Lymphoid malignancy may be the presenting sign of AT. Making this diagnosis may influence therapy of the malignancy. The neurologic manifestations of the disease can be misinterpreted as toxicities of the chemotherapy, and diagnosis of AT allows appropriate genetic counseling for the family.  相似文献   
80.
A new amino acid mixture for incorporation into medical foods for the treatment of hyperphenylalaninemia has been tested in a regular clinic. The mix is designed to be as unobtrusive as possible, consistent with good nutrition. After more than 1 year of trial as a beverage, we have shown that it is safe and well tolerated but that plasma phenylalanine is no better controlled than with some other products. The mix can be incorporated into a large number of different foods without affecting the taste. Occult monitoring of the quantity of medical foods purchased compared with the amounts reported to be consumed in diet histories provides an excellent way to monitor dietary compliance.  相似文献   
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