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131.
132.
Nasopharyngeal carriage of Haemophilus influenzae and Streptococcus pneumoniae was studied in 621 healthy Chinese children and 300 healthy Vietnamese children aged from 2 months to 5 years in Hong Kong. The carriage rate of H, influenzae type b in Vietnamese children was 1.3% (CI 0.04-2.63%); it was zero in Chinese. The carriage rate of non-typable H. influenzae was 5.8% (CI 1.4-7.6%) in Chinese and 65.4% (CI 58.9-69.8%) in Vietnamese. The carriage rates of S. pneumoniae were 10.8% (CI 8.3-13.2%) and 55.7% (CI 50.1-61.3%) in Chinese and Vietnamese children, respectively. Univariate and multivariate logistic regression analyses were performed to search for factors associated with differences in carriage rates of both H. influenzae and S. pneumoniae between Chinese and Vietnamese children. Although older age, smaller living area and parental smoking were associated with higher carriage rates, these could not explain the remarkably low carriage rates of both bacteria in Chinese children.  相似文献   
133.
CJ Hobbs  JM Wynne  AJ Thomas 《Archives of disease in childhood》1995,73(5):465-9; discussion 469-71
After the introduction of the colposcope for the examination of children suspected of being sexually abused in Leeds, a study was undertaken to describe the findings in detail. A total of 109 consecutive prepubertal girls, mean age 70.4 months were assessed including colposcopic genital and anal examination, and peer group review of reports and photographs. Fifty nine children had signs consistent with blunt force penetrating trauma (hymenal transection/major notch, scar, or hymenal attenuation). Transections were encountered most commonly at 6 o'clock (directly posterior). In 46 the hymenal orifice was gaping with thigh abduction only and in 47 the hymenal orifice transverse diameter was greater than 4 mm on labial separation. Overall, physical findings were commonly present and in only two cases were no signs recorded. Non-specific and frequent findings included patterns of labial and introital reddening. Supportive hymenal signs including swelling, rounding of edge, thickening, distortion, and loss of symmetry were common. Labial fusion was present in 20. Urethral dilatation with labial separation was noted in 14. Physical findings including normality are consistent with abuse and even minor anogenital signs as well as negative findings should be documented. Colposcopy and photography are valuable tools in peer review, teaching, and case management.  相似文献   
134.
Influence on fetal growth of exposure to tobacco smoke during pregnancy   总被引:5,自引:0,他引:5  
We analysed the effect of exposure to tobacco smoke during pregnancy on fetal growth parameters in 129 term newborns. Children were classified into four depending on exposure on the basis of a questionnaire completed by the mother. The results confirmed that tobacco smoking reduced weight, length, cranial and thoracic perimeters at birth when exposure was due to either active or passive smoking. Weight deficits of infants whose mothers smoked heavily (458 g) were higher than those whose mothers were exposed to passive smoking (192 g). We conclude that passive smoking is a very important variable and should be taken into account in any study of neonatal growth parameters.  相似文献   
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136.
In a previous work, searching for new drugs with high efficiency and low toxicity, the in vitro antileishmanial activity of a series of seven amidine derivatives against Leishmania amazonensis promastigotes was reported. In order to compare the potential difference in the susceptibility between the two developmental stages of the parasite to these compounds, an analysis of the effects of these amidine derivatives on promastigotes and axenically grown amastigotes of L. amazonensis was carried out. Among the N,N'-diphenyl-4-R-benzamidine (where R = H, Cl, Br, CN, NO2, CH3 and OCH3) derivatives studied, the most active compounds in both developmental stages were those with -Br, -Cl, -NO2, and -OCH3 substituents, the nonsubstituted ones being the least active. However, the susceptibility to the drugs varied in these forms, being higher in promastigotes. The electronic theoretical parameters calculated by molecular modelling using the semi-empirical AM1 method showed good correlation with substituent constant (sigma para, sigma 1 and F). The chemical structure and biological activity relationships were investigated in all compounds, although a small but significant correlation was observed. The obtained results suggest that other factors than the electronic parameters have an influence on the biological response.  相似文献   
137.
We report a patient with a peripheral neuropathy as the first symptom of sarcoidosis. The systemic illness was proved by the presence of typic granulomes in the bone marrow. The fact that sarcoidosis is the cause for the neuropathy is supported by the temporary relation and by the good response of all clinical picture to the corticosteroid therapy.Sarcoid neuropathy can rarely be the presenting feature of sarcoidosis.  相似文献   
138.
Several authors have suggested that it is safe to raise the health standard for nitrate in drinking water, and save money on measures associated with nitrate pollution of drinking water resources. The major argument has been that the epidemiologic evidence for acute and chronic health effects related to drinking water nitrate at concentrations near the health standard is inconclusive. With respect to the chronic effects, the argument was motivated by the absence of evidence for adverse health effects related to ingestion of nitrate from dietary sources. An interdisciplinary discussion of these arguments led to three important observations. First, there have been only a few well-designed epidemiologic studies that evaluated ingestion of nitrate in drinking water and risk of specific cancers or adverse reproductive outcomes among potentially susceptible subgroups likely to have elevated endogenous nitrosation. Positive associations have been observed for some but not all health outcomes evaluated. Second, the epidemiologic studies of cancer do not support an association between ingestion of dietary nitrate (vegetables) and an increased risk of cancer, because intake of dietary nitrate is associated with intake of antioxidants and other beneficial phytochemicals. Third, 2–3 % of the population in Western Europe and the US could be exposed to nitrate levels in drinking water exceeding the WHO standard of 50 mg/l nitrate, particularly those living in rural areas. The health losses due to this exposure cannot be estimated. Therefore, we conclude that it is not possible to weigh the costs and benefits from changing the nitrate standard for drinking water and groundwater resources by considering the potential consequences for human health and by considering the potential savings due to reduced costs for nitrate removal and prevention of nitrate pollution.  相似文献   
139.
随着禽流感病毒H5N1的不断蔓延,越来越有可能发生人类流感的大流行。如果现在发生流感的大流行,不仅还没有有效的疫苗,而且还可能造成抗病毒药物的缺乏。目前尚没有证据表明抗流感药物神经氨酸酶抑制剂(neuraminidaseinhibitor对)禽流感和流感大流行的病毒有效,给予神经氨酸酶抑制剂后,感染H5N1禽流感病毒的患者的死亡率仍然很高。而且流感病毒的耐药会进一步限制抗病毒药物的疗效。假如继发性细菌感染是流感常见且重要的致命性并发症,那么抗生素在人类流感大流行中将占有重要的一席地位。  相似文献   
140.
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