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排序方式: 共有1170条查询结果,搜索用时 15 毫秒
1.
Liver hemangioma: US-guided 18-gauge core-needle biopsy 总被引:6,自引:0,他引:6
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Validity of the 'Ten Questions' for screening serious childhood disability: results from urban Bangladesh 总被引:6,自引:0,他引:6
S S Zaman N Z Khan S Islam S Banu S Dixit P Shrout M Durkin 《International journal of epidemiology》1990,19(3):613-620
A survey of 2576 children aged two to nine years was carried out in Dhaka, Bangladesh, as part of a collaborative study to test the validity of a questionnaire (the Ten Questions) for screening severe childhood disabilities in community settings. Approximately 7% of the children were positive on the screen and this rate was slightly higher in boys than girls. The sensitivity, specificity and negative predictive value of the Ten Questions were perfect or nearly perfect for severe and moderate (serious) disabilities. The positive predictive value was only 22% for serious disabilities, but 70% of children classified as false positives were found to have mild disabilities or other conditions (such as ear infections) for which early detection and treatment could be beneficial. No major age or gender differences in the validity of the questionnaire were apparent, but this finding needs additional study and confirmation with studies based on larger samples. In general, the results indicate that the Ten Questions is a valid tool for screening serious disabilities in children and can potentially improve the efficiency of health services by reducing the number of children requiring attention from professionals. Future studies using the Ten Questions should foster greater attention to the dimensions of childhood disability as a public health problem in the less developed world. 相似文献
4.
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors. 相似文献
5.
The impact of the Safe Kids/Healthy Neighborhoods Injury Prevention Program in Harlem, 1988 through 1991. 总被引:19,自引:6,他引:13
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L L Davidson M S Durkin L Kuhn P O'Connor B Barlow M C Heagarty 《American journal of public health》1994,84(4):580-586
OBJECTIVES. This study evaluated the effectiveness of a community coalition to prevent severe injuries to children in Central Harlem, New York, NY. It was hypothesized that injury incidence rates would decline during the intervention (1989 through 1991) relative to preintervention years (1983 through 1988); that the decline would be greatest for the targeted age group (5 through 16 years) and targeted injury causes (traffic accidents, assaults, firearms, outdoor falls); and that the decline would occur in the intervention community rather than a control community. METHODS. Surveillance of injuries that result in hospitalization and/or death among children in the two communities has been under way since 1983. Data from this surveillance were used to test whether the incidence of severe injury declined during the intervention; other temporal variations were controlled by Poisson regression. RESULTS. The incidence of injury among school-aged children in central Harlem declined during the intervention. The decline was specific to the targeted age group and targeted causes. A nonspecific decline also occurred in the control community. CONCLUSIONS. The declining incidence rate in Central Harlem is consistent with a favorable program effect, but additional investigation of possible secular trend or spillover effects is needed. 相似文献
6.
Studies predict a 50 percent increase in residential long-term care need by the year 2000. Statistics show that the age group served by these facilities is at a much higher risk for sight threatening eye conditions. A review of the current literature as well as original data collected in Ohio indicates that residents in long-term care facilities are underserved with regard to eye care. This paper discusses the need for increased optometric participation in the primary eye care services for residents of long-term care facilities. 相似文献
7.
Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
8.
AE Castellano G Micieli P Bellantonio MG Buzzi S Marcheselli F Pompeo F Rossi G Nappi 《Cephalalgia : an international journal of headache》1998,18(9):622-630
Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks. 相似文献
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B H Campbell B F Dennison G E Durkin M A Strigenz R J Toohill 《Otolaryngology--head and neck surgery》1986,95(5):566-573
There has been widespread use of periodic dilatations in the management of subglottic stenosis. However, some authorities have questioned the value in the overall rehabilitation of patients affected by this disorder. The first phase of this study included fourteen large dogs in which acute subglottic lesions were created by use of a high-speed electric drill and electrocautery. Twelve animals served as the experimental group and two animals were controls. Obstructing lesions developed in all the animals within 7 to 21 days. When at least a 50% obstruction developed in an animal, a treatment plan was instituted that included at least weekly dilatation, removal of granulations, and administration of intralesional steroids and/or systemic steroids and antibiotics. The two control animals became totally obstructed and were killed. Varying degrees of subglottic stenosis developed in all twelve experimental animals after 8 weeks of dilatation, but none required a tracheotomy. These twelve animals were then subjected to 8 additional weeks of dilatation and antibiotics, and supplemental steroids were used in some animals from this study. It can be concluded that early periodic dilatation and granulation removal in the acutely injured subglottis is effective in prevention of severe stenosis, late periodic dilatations in chronic subglottic stenosis are not helpful in further alleviation of obstruction, the concomitant use of antibiotics and systemic steroids did not appreciably prevent or alter the development of subglottic stenosis, and the concomitant use of intralesional steroids appeared to be of benefit in the management of chronic acquired subglottic stenosis. 相似文献