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991.
Many delinquent youth stop offending sometime in late adolescence or early adulthood. However, little is known about individual differences in desistance and which factors promote or inhibit desistance. In the current study, young males in the oldest sample of the Pittsburgh Youth Study were followed from ages 13 to 25. About one-third became persistent serious delinquents between ages 13 and 19. Out of that group, almost 40% desisted in serious offending between ages 20 and 25. Significantly more of the desisters, compared to the persisters in serious delinquency, had been employed or in school. Bivariate analyses demonstrated many predictors of desistance of serious delinquency in early adulthood in the domains of individual, family, and peer factors measured from early adolescence onward. Multiple regression analyses showed that the following promotive factors were associated with desistance: low physical punishment by parents in early adolescence and being employed or in school in early adulthood. The following risk factors were inversely associated with desistance during early adulthood: serious delinquency during late adolescence, hard drug use, gang membership, and positive perception of problem behavior in early adulthood. The article discusses the implications of promotive and risk factors for preventive interventions. 相似文献
992.
Helbostad JL Askim T Moe-Nilssen R 《Archives of physical medicine and rehabilitation》2004,85(6):993-999
OBJECTIVE: To investigate short-term repeatability of a posturographic quiet standing test protocol in people with hemiparesis and in frail older adults. DESIGN: Test-retest design, using 5 different quiet standing task conditions in which size and compliance of the support surface, visual influence, and cognitive demands were manipulated. Retest was performed after 15 minutes. SETTING: Rehabilitation units and day care center. PARTICIPANTS: Twenty-three people with stroke (mean age, 74.4y) and 16 frail older adults (mean age, 82.1y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Repeatability of trunk acceleration root mean square by within-subject standard deviation, coefficient of variation, and intraclass correlation coefficients (ICCs). RESULTS: The ICC(1,2) ranged from.13 to.75 for people with hemiparesis and from.73 to.92 for frail older adults when tested with their eyes open. The least demanding task condition gave the best repeatability. Standing with eyes closed resulted in very low ICC(1,2) in people with hemiparesis (.16) and in frail older adults (-.18). Interpretation of the results was similar for the other 2 reliability measures. CONCLUSIONS: A mean of 2 repeated measures gave adequate repeatability for frail older adults but not for people with stroke when they were tested with their eyes open. This study showed the importance of establishing short-term repeatability relative to each clinical population in which such tests are used. 相似文献
993.
Jenni R Matthews F Aschkenasy SV Lachat M van Der Loo B Oechslin E Namdar M Jiang Z Kaufmann PA 《Ultrasound in medicine & biology》2004,30(5):633-637
We report on a novel procedure for invasive volumetric blood flow measurements using a commercially available Doppler flow wire system, which could, until now, only measure flow velocity. We here describe a method applicable in vivo to generate both velocity and cross-sectional area information from the same pulsed-wave Doppler signal for volumetric flow assessment. We demonstrate its feasibility and validation in vivo in pig coronary arteries. Our Doppler-derived volumetric flow measurements were compared with the respective transit-time flow and showed an excellent correlation (r = 0.969; p < 0.0001). Agreement between transit-time and Doppler-derived flow measurements could be observed for flow conditions ranging from 30 to 180 mL/min. The mean values for the two methods were 71.4 +/- 43.7 mL/min and 71.3 +/- 42.2 mL/min, respectively. We conclude that this technique might possibly be introduced into future clinical practice as an invasive procedure of choice for the assessment of volumetric blood flow. 相似文献
994.
Yücel N Lefering R Maegele M Max M Rossaint R Koch A Schwarz R Korenkov M Beuth J Bach A Schierholz J Pulverer G Neugebauer EA 《The Journal of antimicrobial chemotherapy》2004,54(6):1109-1115
OBJECTIVE: Central venous catheters (CVC) are a major cause of nosocomial bloodstream infections. Catheters modified with miconazole and rifampicin that constantly and slowly release antimicrobial substances are assumed to be beneficial in reducing rates of colonization and catheter-related infections. DESIGN AND SETTING: Prospective controlled non-blinded randomized clinical trial in two German university hospitals. PATIENTS: 223 adult inpatients with CVC between October 2000 and February 2002. Baseline characteristics, APACHE II score and therapeutic interventions were comparable. INTERVENTION: Randomization to receive either a miconazole and rifampicin modified catheter (n=118) or a standard triple-lumen CVC (n=105). MEASUREMENTS, DEFINITIONS: Microbiological evaluation was done after CVC removal. A catheter was considered colonized if growth of > or =15 cfu was found by semi-quantitative roll-plate technique from a proximal or distal catheter segment. A catheter-related infection (CRI) was defined as a colonized catheter with local signs of inflammation. A catheter-related bloodstream infection (CR-BSI) was defined as a colonized catheter with isolation of the same organism from the patient's blood with accompanying clinical signs of infection. RESULTS: A colonization of CVC was observed in six patients (5.1%) with a modified catheter and 38 patients (36.2%) with a standard catheter (P < 0.001). Five patients in the modified group (4.2%) and 18 in the standard group (17.1%) developed CRI (P=0.002). One assumed CR-BSI was detected in the standard group, with none in the modified group. No adverse effects related to the modified catheters and no antimicrobial resistance were observed. CONCLUSION: CVC supersaturated with miconazole and rifampicin were associated with a significantly lower risk for catheter colonization and catheter-related infections compared to standard catheters. 相似文献
995.
996.
BACKGROUND: Liberal transfusion strategy increases the risk of acute lung injury (ALI), but specific transfusion-related factors have not been characterized. We tested the hypotheses that storage age and specific type of blood products are associated with increased risk of ALI in mechanically ventilated patients. STUDY DESIGN AND METHODS: From a database of mechanically ventilated patients, we identified those who received blood products during the first 48 hours of intensive care. We extracted information about underlying ALI risk factors as well as the type, amount, and shelf age of administered blood products. Outcome was assessed by an independent, blind review of chest radiographs and clinical findings. RESULTS: Of 181 patients transfused during the first 48 hours of mechanical ventilation, 60 (33%) developed ALI. There was no difference in average duration of red blood cells storage between patients who did and did not develop ALI (median, 18.5 vs. 17.5 days; p = 0.22). In a multivariable logistic regression analysis, important risk factors associated with the development of ALI were thrombocytopenia (odds ratio, 5.9; p = 0.004) and transfusion of fresh frozen plasma (odds ratio, 3.2; p = 0.023). CONCLUSION: Thrombocytopenia and transfusion of fresh frozen plasma, but not storage age of red blood cells, were associated with the development of ALI in this cohort of mechanically ventilated patients. 相似文献
997.
Blood supply and oxidative metabolism in muscle biopsies of female cleaners with and without myalgia
OBJECTIVES: Pathomechanisms of work-related myalgia are poorly understood. Myalgia is thought to be caused by excitation of nociceptors present in the muscular tissue but not in the muscle fiber itself. Muscle contraction in combination with hypoxia is known to excite nociceptors. Morphologic analysis can contribute to the knowledge of the excitation of nociceptors. This study thoroughly examines the morphology of the trapezius muscle's capillary supply and signs of disturbed oxidative metabolism to understand their role in work-related myalgia. METHODS: Surgical trapezius muscle biopsies were obtained from 25 female cleaners with long-standing work-related myalgia, 25 female cleaners without trapezius myalgia, and 21 healthy teachers. Enzyme and immunohistochemical stainings were performed to highlight fibers with aberrant intermyofibrillar patterns, indicating a disturbed oxidative metabolism (also known as moth-eaten fibers) and a disturbed capillary supply of different fibers. RESULTS: A significantly lower number of capillaries per fiber area in cleaners suffering from myalgia compared with cleaners without trapezius myalgia was found. Moth-eaten fibers were found in the 3 groups, but these fibers were significantly more prevalent in the groups of cleaners than in the healthy teacher group. CONCLUSION: This work indicates that the capillary supply of trapezius is affected in work-related trapezius myalgia. More studies are needed to understand possible mechanisms that would explain the occurrence of moth-eaten fibers. 相似文献
998.
999.
BACKGROUND: A high rate of sensitization and clinical allergy to latex proteins has been reported in health care personnel. This is thought to be due to increased occupational exposure especially to natural rubber latex (NRL) gloves with an estimated prevalence varying widely (2.8-18%). OBJECTIVE: This was a longitudinal study to monitor a cohort of first-year dental students throughout 4 study years during exposure to powder-free gloves. Their atopic status was determined by skin prick testing using a panel of common allergens, and any sensitivity to latex proteins and the cross-reacting food allergens assessed. METHODS: Skin prick testing was carried out on the volunteers using latex, avocado, kiwi, banana, grass pollens, tree pollen, house dust mite and cat dander. Each volunteer completed a questionnaire detailing allergic history and any previous latex exposure. RESULTS: Skin prick testing showed a 65% incidence of atopy in the longitudinal study group. Initial latex skin testing was positive in 3 of the 63 students followed throughout their period of study. Subsequent testing gave a negative result in one student and one declined retesting. The third continued to give a positive response on each testing; she wore only nitrile gloves and remained free of clinical NRL allergy symptoms. No student developed latex sensitivity during the 5 yr of this study. CONCLUSION: Exposure to powder-free latex gloves was not associated with subsequent sensitization over 5 yr in a population with a high atopic incidence. 相似文献
1000.
The identification and subsequent development of the GABA transport inhibitor tiagabine has confirmed the important role that GABA transporters play in the control of CNS excitability. Tiagabine was later demonstrated to be a selective inhibitor of the GABA transporter GAT1. Although selective for GAT1, tiagabine lacks cell type selectivity and is an equipotent inhibitor of neuronal and glial GAT1. To date, four GABA transporters have been cloned, i.e., GAT1-4. The finding that some of these display differential cellular and regional expression patterns suggests that drugs targeting GABA transporters other than GAT1 might offer some therapeutic advantage over GAT1 selective inhibitors. Furthermore, it is particularly interesting that several recently defined GABA transport inhibitors have been demonstrated to display a preferential selectivity for the astrocytic GAT1 transporter. That cellular heterogeneity of GAT1 plays a role in the control of CNS function is confirmed by the demonstration that inhibition of astrocytic GABA uptake is highly correlated to anticonvulsant activity. At the present time, a functional role for the other GABA transporters is less well defined. However, recent findings have suggested a role for the mouse GAT2 (homologous to the human betaine transporter) in the control of seizure activity. In these studies, the non-selective GAT1 and mouse GAT2 transport inhibitor EF1502 (N-[4,4-bis(3-methyl-2-thienyl)-3-butenyl]-3-hydroxy-4-(methylamino)-4,5,6,7-tetrahydrobenzo[d]isoxazol-3-ol) was found to exert a synergistic anticonvulsant action when tested in combination with the GAT1 selective inhibitors tiagabine and LU-32-176B (N-[4,4-bis(4-fluorophenyl)-butyl]-3-hydroxy-4-amino-4,5,6,7-tetrahydrobenzo[d]isoxazol-3-ol). Additional studies will be required to define a role for the other GABA transporters and to further identify the functional importance of their demonstrated cellular and regional heterogeneity. A summary of these and other issues are discussed in this brief review. 相似文献