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991.
992.
Granuloma annulare is a benign, relatively common dermatosis in childhood. The subcutaneous form is rare, and lesions typically occur on the legs, buttocks and scalp. We report a case of a deep granuloma annulare confined to the palms of the hands in a 2-year-old child.  相似文献   
993.
994.
Treating nocturnal enuresis in children: review of evidence.   总被引:1,自引:0,他引:1  
BACKGROUND: Childhood nocturnal enuresis (bedwetting) affects many families. Although it has a high rate of spontaneous remission, bedwetting may bring social and emotional stigma, stress, and inconvenience to both the child with enuresis and his or her family. DESIGN: Summary of systematic reviews of treatment for nocturnal enuresis in children, published in the Cochrane Library, using evidence only from randomized and quasi-randomized trials to compare interventions. Interventions included behavioral, alarm, and pharmacologic treatments. SETTING AND METHODS: Six Cochrane Reviews contributed evidence to this review: simple behavioral interventions, alarms, complex behavioral or educational interventions, desmopressin, tricyclics and related drugs, and other drugs. SUBJECTS: The participants were children (usually up to the age of 16). RESULTS: Much of the available evidence was of poor quality, and there were few direct comparisons between different types of intervention. Simple behavioral Interventions, such as reward systems, are widely used as standard first-line treatment, but they require a high level of parental involvement. There is currently little evidence to show that these interventions work, but they may be worth trying because they have only a few adverse effects. The use of an alarm intervention reduced nighttime bed wetting in a majority of children both during and after treatment. Overlearning or dry-bed training may reduce the relapse rate. Before embarking on alarm treatment, families need to be made aware of both the time and the high level of parental involvement necessary to attain success. Drug therapy, such as desmopressin and tricyclics, reduced the number of wet nights per week compared with placebo but only while the drug was used. Patients and their families need to be warned about possible side effects of some of the drugs. CONCLUSIONS: Alarms are the most effective treatment for nocturnal enuresis in children, but desmopressin may be considered for temporary relief.  相似文献   
995.
BACKGROUND AND PURPOSE: Talairach-based parcellation (TP) of human brain magnetic resonance imaging (MRI) data has been used increasingly in clinical research to make regional measurements of brain structures in vivo. Recently, TP has been applied to pediatric research to elucidate the changes in regional brain volumes related to several neurological disorders. However, all freely available tools have been designed to parcellate adult brain MRI data. Parcellation of neonatal MRI data is very challenging owing to the lack of strong signal contrast, variability in signal intensity within tissues, and the small size and thus difficulty in identifying small structures used as landmarks for TP. Hence the authors designed and validated a new interactive tool to parcellate brain MRI data from newborns and young infants. METHODS: The authors' tool was developed as part of a postprocessing pipeline, which includes registration of multichannel MR images, segmentation, and parcellation of the segmented data. The tool employs user-friendly interactive software to visualize and assign the anatomic landmarks required for parcellation, after which the planes and parcels are generated automatically by the algorithm. The authors then performed 3 sets of validation experiments to test the precision and reliability of their tool. RESULTS: Validation experiments of intra-and interrater reliability on data obtained from newborn and 1-year-old children showed a very high sensitivity of >95% and specificity >99.9%. The authors also showed that rotating and reformatting the original MRI data results in a statistically significant difference in parcel volumes, demonstrating the importance of using a tool such as theirs that does not require realignment of the data prior to parcellation. CONCLUSIONS: To the authors' knowledge, the presented approach is the first TP method that has been developed and validated specifically for neonatal brain MRI data. Their approach would also be valuable for the analysis of brain MRI data from older children and adults.  相似文献   
996.
997.
Controversy about the value of the post-coital test (PCT) has prompted us to re-analyse data from 207 couples, originally studied between 1982 and 1983, with at least 12 months' infertility at presentation, complete diagnostic information and exclusion of female factors, to clarify the effect of duration of infertility on the prediction of conception. In couples with less than 3 years infertility and a positive PCT, 68% conceived within 2 years compared with 17% of those with a negative result. After 3 years, corresponding rates were 14% and 11%. The relative risks of conception [95% confidence interval (CI)] calculated using the Cox's proportional hazards model were 0.23 (0.12-0.43) for a negative PCT (reference positive PCT) and 0.25 (0.13-0.51) for more than 36 months infertility (reference 12-23 months). Semen analysis had no extra predictive power given the duration of infertility and the PCT. The PCT is an effective predictor of conception where defined female causes of infertility are absent and duration of infertility is less than 3 years. Once infertility is prolonged (beyond 3 years) the conception rate is low even with a positive test because a large proportion of couples remaining childless so long have true unexplained infertility. Use of the PCT will enable clinicians to allocate scarce, expensive and invasive resources effectively.  相似文献   
998.
White cell-poor blood components are useful in patients with white cell antibodies. White cells are efficiently removed by two different filters, Imugard and Erypur, which have used saline as the filter solution. This study evaluated these filters as to their production of white cell-poor platelets. Pools of random-donor platelet concentrates were filtered. Prefiltration and postfiltration samples were evaluated for percentages of platelet recovery, white cell (WBC) removal, and platelet function. The two filter solutions tested were normal-strength saline (NSS) and fresh-frozen plasma (FFP). Postfiltration samples using NSS showed no measurable platelet aggregation with ADP, epinephrine, or collagen. However, with FFP, both filters showed 100 percent platelet aggregation with ADP, epinephrine, and collagen. The FFP filter solution provided excellent white cell removal in both filters (Imugard: 100% WBC removal or less than 1.0 X 10(6) residual WBC; Erypur: 99.5% removal or greater than 1.0 X 10(7) residual WBC); however, platelet recovery was better with Imugard (95%) than with Erypur (55%). The filtration procedure is an excellent method for the preparation of white cell-poor platelets; however, the quantity of the saline solution recommended for the filtering of red cells must be minimized for platelets.  相似文献   
999.
Heparin therapy in the Chinese--lower doses are required   总被引:1,自引:0,他引:1  
Warfarin requirements are lower in the Chinese, but it is not known if this applies to heparin. We investigated the optimal dose for heparin therapy in Chinese patients, and to assess relationship between i.v. heparin dosage and anticoagulation efficacy. One hundred Chinese patients requiring intravenous heparin therapy were given an initial bolus followed by continuous intravenous infusion. The main outcome measures were: (i) Efficacy of anticoagulation assessed by blood coagulation studies (APTT) compared to heparin dosage, (ii) Determinants of dosage variation-age, gender, body weight, height, indication for heparin therapy and number of medications, other disease, and serum albumin level. It was found that the mean therapeutic infusion dose requirement of heparin was 848.7 +/- 274.7 units/h, 79% required a dose of 1000 units/h or less. Heparin dose correlated negatively with age (r = -0.40; p < 0.001) and positively with weight (r = 0.44 p < 0.001) and height (r = 0.49; p < 0.001). Chinese subjects require lower heparin doses (about 800 units/h) than usually recommended for Caucasians (usual dose 1000-1500 units/h). This can be partly explained by the lower body weight in Chinese patients.   相似文献   
1000.
OBJECTIVE: To determine the frequency of detection of human herpesvirus-8 (HHV-8) in HIV-related oral ulcers. DESIGN: Analysis of archived biopsy material. METHODS: Nested polymerase chain reaction of DNA extracts. RESULTS: HHV-8 DNA was detected in six of 10 oral ulcers of HIV-positive patients without oral Kaposi's sarcoma (KS) lesions and five of 11 oral KS lesions. The positive non-KS samples were derived from various oral sites. CONCLUSIONS: In HIV-positive people, HHV-8 can infect oral tissues that are not affected by KS.  相似文献   
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