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排序方式: 共有538条查询结果,搜索用时 15 毫秒
41.
S T Ennett E B Federman S L Bailey C L Ringwalt M L Hubbard 《The Journal of adolescent health》1999,25(5):344-353
PURPOSE: To examine characteristics of youth homelessness associated with engaging in risk behaviors for human immunodeficiency virus (HIV). METHODS: The sample included 288 currently homeless or runaway Washington, DC youth aged 14-21 years. Measures were self-reported homelessness characteristics, unsafe sexual behavior, injection drug use, and background characteristics. Bivariate and multivariable analyses of the relationships between homelessness characteristics and HIV risk behaviors were conducted. RESULTS: Both male (n = 140) and female (n = 148) participants reported high rates of unsafe sexual behaviors, but low rates of injection drug use. HIV risk was significantly associated in bivariate analyses with severity of homelessness circumstances (i.e., spending the night in public place or with strangers, going hungry, and participating in the street economy), the duration of homelessness (i.e., greater number of episodes of homelessness, longer time length of current episode), and specific reasons for being homeless (i.e., thrown out). In addition, sexual victimization and older age were associated with increased HIV risk. In multivariable models, a smaller set of these homelessness characteristics remained significant independent correlates and explained a substantial amount of the variation in the HIV risk indices for both males and females. CONCLUSIONS: The results contribute to greater theoretical understanding of the characteristics of homelessness associated with increased risk of HIV infection within this vulnerable population of youth. The associations between homelessness characteristics and HIV risk suggest the need for HIV prevention efforts to focus directly on ameliorating the homelessness circumstances of youth. 相似文献
42.
Michael Girardi M.D. Grace L. Federman M.D. Jennifer M. McNiff M.D. 《Pediatric dermatology》1999,16(4):281-284
Basaloid follicular hamartoma (BFH) is one of several benign skin tumors that may occur in multiple and solitary forms. While the histologic findings of BFH may be observed in a variety of clinical settings, familial multiple BFH represents a distinct clinical entity characterized by tiny flesh-colored papules scattered predominantly over the face. We present two sisters with this rare condition and review the clinical and histologic differential diagnosis of familial multiple BFH. 相似文献
43.
M. CONY PH. DONATIEN † C. BEYLOT ‡ M. GÉNIAUX§ J. MALEVILLE J.H. BEZIAN† A. TAÏEB † 《Clinical and experimental dermatology》1990,15(6):410-414
A living cellular allogeneic dressing made up of cultured keratinocytes adhering to a collagen film was used to treat 20 leg ulcers of various aetiologies in 16 patients. A reduction in pain was noted in 80% of cases, and promotion of granulation tissue in the ulcer bed in 70% of cases. In 10 patients, epithelialization of 71 +/- 29% of the ulcer was noted at Day 30. 相似文献
44.
45.
Gholam A. Peyman Howard Charles Magdy E. Tawakol Jay Federman Fumitaka Ando 《International ophthalmology》1987,11(2):77-78
We used a Nd:YAg laser fit with a fiberoptic cord and sapphire tip to drain subretinal fluid externally in patients with rhegmatogenous retinal detachment. The direct contact between the laser and the choroid allowed for controlled cutting and coagulation of the intervening choroidal vasculature. The drainage was successfully achieved with no complication.Supported in part by a grant from Research to Prevent Blindness, Inc., New York City, and by Core grant EY1972 from the National Eye Institute, Bethesda, MD. 相似文献
46.
47.
Blood loss and replacement in total hip arthroplasty: a multicenter study. The Preoperative Autologous Blood Donation Study Group 总被引:1,自引:0,他引:1
To determine blood loss, the number of transfusions, and the hemoglobin levels achieved in patients via transfusion in the course of total hip arthroplasty, 324 patient records from 1987 through 1989 were reviewed at three university and three community hospitals. Calculated blood loss was 3.2 +/- 1.3 units in primary procedures and 4.0 +/- 2.1 units in revision procedures (mean +/- SD). Of 777 red cell units transfused, 455 (59%) were autologous units. Transfused patients received 2.0 +/- 1.8 units for primary procedures and 2.9 +/- 2.3 units for revision procedures (mean +/- SD). The maximum number of units given to 95 percent of the transfused patients was 4 for primary procedures and 6 for revision procedures. The mean postoperative hemoglobin level after all transfusions was 103 to 110 g per L, regardless of patient age group of physical status, autologous donor status, or hospital. No difference in length of hospital stay was observed for patients less than 65 years old with hemoglobin concentrations of 80 to 139 g per L at discharge. 相似文献
48.
Total radical trapping antioxidant potential (TRAP) and exercise 总被引:1,自引:0,他引:1
Sharpe PC; Duly EB; MacAuley D; McCrum EE; Mulholland C; Stott G; Boreham CA; Kennedy G; Evans AE; Trinick TR 《QJM : monthly journal of the Association of Physicians》1996,89(3):223-228
The relationship between physical activity, physical fitness and total
radical trapping antioxidant potential (TRAP) was examined in the Northern
Ireland Health and Activity Survey. This was a cross-sectional population
study (n = 1600) using a two-stage probability sample of the population.
TRAP was calculated using the sum of the individual serum antioxidant
concentrations (urate, protein thiols, ascorbate, alpha tocopherol and
bilirubin) multiplied by their respective stoichiometric values. Physical
fitness was determined by estimation of VO2max by extrapolation from
submaximal oxygen uptake, and physical activity was recorded by
computer-assisted interview. Mean serum TRAP concentrations were
significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared
to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female
smokers had significantly lower TRAP values than non-smokers (males p <
0.0001, females p = 0.02). In females, there was a positive relationship of
TRAP with age (p < 0.001) and body mass index (p < 0.001) but a
negative relationship with physical fitness (p < 0.05). The known
beneficial effects of exercise and activity do not appear to be directly
mediated through increased antioxidant status.
相似文献
49.
Platelet membrane glycoprotein changes during the preparation and storage of platelet concentrates 总被引:6,自引:0,他引:6
Previous studies of platelet membrane glycoproteins during blood bank storage have reported conflicting results. This study assessed two major plasma membrane glycoproteins (GP Ib and GP IIb), an alpha-granule membrane protein (GMP-140), and the concentration of platelet membrane microparticles in cell-free plasma during routine hospital blood bank platelet storage. 125I-monoclonal antibody binding was used to measure membrane glycoproteins on the surface of intact platelets and to measure the concentration of membrane microparticles in cell-free plasma. Platelet concentrates were stored at room temperature in polyolefin bags for 7 days. In this blood bank, two types of rotators are routinely used for platelet concentrate storage: a 2-rpm circular tumbler rotator and a 6-rpm elliptical rotator. Different results were obtained with the rotators. With the tumbler rotator, there was no loss of platelets and antibody binding to GP Ib remained normal. With the elliptical rotator, one third of platelets were lost into clumps during storage, and a 50 percent decrease of antibody binding to GP Ib occurred in the remaining single platelets. There was no loss of antibody binding to GP IIb with either rotator. Antibody binding to GMP-140 increased equally in both rotators indicating that the remaining single platelets had secreted about 16 percent of their alpha-granule contents. The plasma concentration of platelet membrane microparticles was greater in the bags stored in the elliptical rotator. These results indicate that it is possible to maintain the normal concentration of platelet membrane glycoproteins Ib and IIb during 7 days of room-temperature blood bank storage.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
50.
EB Caron Kristin Bernard Mary Dozier 《Journal of clinical child and adolescent psychology》2018,47(6):S35-S46
Understanding mechanisms and active ingredients of intervention is critical to training clinicians, particularly when interventions are transported from laboratories to communities. One promising active ingredient of parenting programs is clinicians’ in vivo feedback regarding parent–child interactions. The present study examined whether a form of in vivo feedback, in the moment commenting, predicted treatment retention and parent behavior change when the Attachment and Biobehavioral Catch-up (ABC) intervention was implemented in a community setting. Observational data were collected from 78 parent–child dyads (96% mothers; M age = 29 years; 81% minority; infants’ M age = 12 months; 90% minority) across 640 sessions conducted by 9 clinicians (100% female, M age = 39; 67% minority) in Hawaii. Parental behavior was assessed with a semistructured play task before and after intervention. Clinicians’ in-the-moment feedback to parents was assessed from intervention session videos. Clinicians’ frequency and quality of in-the-moment feedback predicted change in parental intrusiveness and sensitivity at posttreatment. Frequency of in-the-moment feedback also predicted likelihood of retention. Hierarchical linear modeling demonstrated strong support for these associations at the between-clinician level, and limited additional support at the within-clinician (i.e., between-case) level. Thus, a hypothesized active ingredient of treatment, in-the-moment feedback, predicted community-based ABC outcomes. The results complement lab-based evidence to suggest that in vivo feedback may be a mechanism of change in parenting interventions. Helping clinicians to provide frequent, high-quality in vivo feedback may improve parenting program outcomes in community settings. 相似文献