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BACKGROUND: The aim was to determine the influence of the socioeconomic status of the family and the hygienic practices in the home on the prevalence of head lice infestation in children. METHODS: The study was carried out by analyzing the answers to a standardized epidemiological questionnaire given to parents of school children aged 4-17 in Bet Shemesh, a medium-sized urban town 25 km from Jerusalem. RESULTS: Of 3,000 questionnaires distributed, 958 (31.9%) were completed and returned. The majority of the children (72.4%) had been previously infested with lice. Half of them had other family members, mainly brothers and sisters, who had been infested in the past with lice. In 97.5% of the families the mother was responsible for examining the children for lice, and for carrying out treatment when infestation was present. An association was found between presence of lice infestation and mother's education, age of child, and frequency of shampooing, combing, and examination for lice. There was no association between infestation rates and mother's country of origin, crowding in the home, and the sharing of combs, brushes, hats, scarves, towels, and clothes. CONCLUSIONS: There is evidence that the incidence of lice infestation depends on the hygienic practices in the home rather than on the socioeconomic status of the family or sharing of personal articles among family members.  相似文献   
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Benign intracranial hypertension (BIH) is reported in three children from Australia and one from New Zealand, who were being treated with recombinant human growth hormone (rhGH). Three males and one female, aged between 10.5 and 14.2 y, developed intracranial hypertension within 2 weeks to 3 months of starting treatment. A national database, OZGROW, has been prospectively collecting data on all 3332 children treated with rhGH in Australia and New Zealand from January 1986 to 1996. The incidence of BIH in children treated with growth hormone (GH) is small, 1.2 per 1000 cases overall, but appears to be greater with biochemical GHD (<10IUml -1), i.e. 6.5/1000 (3 in 465 cases), relative risk 18.4, 95% confidence interval 1.9-176.1, than in all other children on the database. The incidence in patients with Turner's syndrome was 2.3/1000 (1 in 428 cases). No cases in patients with partial GHD (10–20 IUml -1) or chronic renal failure were identified. Possible causative mechanisms are discussed. The authors'practice is now to start GH replacement at less than the usual recommended dose of 14IUm-2 week-1 in those children considered to be at high risk of developing BIH. Ophthalmological evaluation is recommended for children before and during the first few months following commencement of rhGH therapy and is mandatory in the event of peripheral or facial oedema, persistent headaches, vomiting or visual symptoms. The absence of papilledema does not exclude the diagnosis.  相似文献   
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The longitudinal history and temporal stability of total sexual outlet (TSO) in a group of outpatient males with paraphilias (PA) and paraphilia-related disorders (PRD) was assessed. Based on extant normative data from contemporary population-based surveys of sexual behavior, it was hypothesized that a persistent TSO of 7 or more orgasms/week for a minimum duration of 6 months be considered as the lower boundary for hypersexual desire in males. In almost all statistical analyses, the PA (n = 65) and PRD (n = 35) groups were not statistically different. The mean current TSO (PA, 7.4 ± 5.7; PRD, 8.0 ± 4.2) as well as the current average time consumed in all unconventional sexual behaviors (1–2 hr/day) were not statistically different. Unconventional sexual behaviors (i.e., related to PAs or PRDs) leading to orgasm constituted 77% of current TSO. In the combined group (n = 100), 72% (n = 72) reported a hypersexual TSO of 7 or greater. Age of onset of hypersexual TSO in the PAs (19.2 ± 6.8 years; range 10–43) and the PRDs (21.0 ± 8.6; range 10–46) and the duration of hypersexual TSO (PA, 11.1 ± 11.2 years; PRD, 10.5 ± 9.1) were not significantly different. Fifty-seven males (57%) reported a TSO of 7 or more for a minimum duration of 5 years. Clinical implications of reconceptualizing PAs and PRD as sexual desire disorders are discussed.  相似文献   
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Using a newly devised 50-channel photometer which records the opacity of growing bacterial cultures, it was shown that the time taken by cultures diluted 1/1000 in fresh broth to reach 50% of the opacity of a fully grown culture was inversely related to the concentration of organisms in the original culture. This relation was used to determine the numbers of survivors after exposure to benzylpenicillin and gentamicin alone and in combination. The procedure is commended as a labour-saving and potentially rapid method of obtaining comprehensive information on the bactericidal action and interaction of antibiotics.  相似文献   
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The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
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Summary Binding to rat brain- and-adrenergic, muscarinic cholinergic, dopamine and opiate receptors was measured at 4-hour intervals throughout a 24-hour period in animals, chronically treated with fluphenazine, and in controls. Drug treatment significantly changed characteristics of the circadian rhythms in all 5 receptors. In the presence of the drug the 24-hour mean binding to the dopamine receptor was decreased; to the other 4 receptors it was increased. Moreover, there were changes in the timing of the maximal receptor binding (phase-position) and in the amplitude of the rhythms. These results extend previous studies, showing that chronic neuroleptic treatment not only affects the dopamine receptors, but also other neurotransmitter receptors, profoundly modifying their temporal organisation.  相似文献   
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