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排序方式: 共有1124条查询结果,搜索用时 15 毫秒
1.
AbstractThe leading cause of death of adolescents in developed countries is injury. Alcohol is a major contributor to adolescent injury. Most of the injury deaths in youth are caused by traffic crashes. Driving under the influence (DUI) and riding with a driver who is under the influence (RUI) of alcohol increase the risk of road crash. The focus of this study is how adolescents’ risk of DUI and RUI differ in relation to their experience of parental control and peer pressure to substance use, other risky behaviours and leisure time activities. The analyses are based on data from the European School Survey Project on Alcohol and Other Drugs collected from 15- to 16-year-old Finnish adolescents in 2015 (n?=?4049, response rate 88.7%). The study shows that problems tend to entangle in some adolescent groups in which DUI and RUI are also more common. Adolescents with higher probability of using various substances, of starting alcohol use at young age, of experiencing weak parental control, and high peer pressure are at higher risk of DUI and RUI. The results indicate that professionals and authorities handling underage DUI and RUI ought to consider adolescents’ situation as a whole. 相似文献
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Evidence of sustained skeletal benefits from impact-loading exercise in young females: a 3-year longitudinal study. 总被引:4,自引:0,他引:4
Jaana A Nurmi-Lawton Adam D Baxter-Jones Robert L Mirwald Jacki A Bishop Patricia Taylor Cyrus Cooper Susan A New 《Journal of bone and mineral research》2004,19(2):314-322
The skeletal effects from intensive exercise throughout puberty are undefined. Forty-five female gymnasts and 52 controls were studied over 3 years, including a heredity aspect. The effects of size, maturity, exercise, and diet were identified using a multilevel regression model. Results demonstrated sustained skeletal benefits resulting from exercise throughout all stages of pubertal development. INTRODUCTION: Weight-bearing exercise is beneficial for peak bone mass development. However, whether skeletal benefits achieved with exercise are maintained if training remains intensive throughout the pubertal years is not entirely clear. The influence of familial resemblance for bone mass remains undefined in physically active versus inactive children. The aim of this study was to investigate the long-term influences of impact-loading exercise on bone quantity and quality in young females after controlling for growth, maturation, and hereditary factors. MATERIALS AND METHODS: At baseline, 45 gymnasts (G) and 52 normally active controls (C) 8-17 years of age were recruited. Anthropometry, diet, physical activity, and quantitative ultrasound (QUS) were measured annually for 3 consecutive years. DXA scans of total body (TB) and lumbar spine (LS) bone mineral content (BMC) and density (BMD) were taken three times at 1-year intervals. A multilevel regression model was fitted, and the independent effects of body size, maturity, physical activity, and diet were identified over time. To assess heredity influences, 27 G mothers and 26 C mothers volunteered for cross-sectional measurements of anthropometry, QUS, and BMC/BMD. RESULTS AND CONCLUSIONS: Gymnasts were smaller and lighter (as were their mothers) than controls, but they had significantly higher QUS and axial and appendicular BMC and BMD, with > 170 g more bone mineral in TB across puberty (after adjustment for maturity [years from peak height velocity], height, weight, energy, and protein intake). Gymnasts had up to 24-51% higher BMC and 13-28% higher BMD, depending on skeletal site. These results provide evidence of sustained skeletal benefits from impact-loading exercise, which are unlikely to result entirely from heredity, throughout pubertal years. 相似文献
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慢性肝病、原发性肝癌病人血清、肝组织纳米细菌的检测 总被引:4,自引:0,他引:4
目的 研究慢性肝病和原发性肝癌病人血清、组织中纳米细菌(NB)感染,为其发生机制提供新的认识。方法 55例慢性肝病(25例慢性乙肝和30例肝炎后肝硬化)、43例肝癌病人和336例健康人血清采用ELISA、免疫组化和钙染色;53例慢性肝病(28例慢性乙肝和25例肝硬化)、43例肝癌和15例对照肝组织行免疫组化染色,部分阳性组织透射电镜观察。结果 (1)慢性肝病、肝癌病人和健康人血清ELISA检测阳性率分别为20.0%、9.3%和8.0%,慢性肝病NB感染率高于健康人(P〈0.05)。免疫组化染色感染率分别为14.5%、4.7%和5.7%(P〈0.05)。钙染色分别为7.3%、4.7%和6.5%(P〉0.05)。(2)慢性肝病、癌及癌旁、对照组免疫组化阳性率分别为:20.8%、16.3%、14.0%和0%(P〉0.05)。部分肝癌和癌旁组织透射电镜观察发现纳米细菌样微生物结构(3/5)。结论 部分慢性肝病、肝癌病人血清、组织中存在纳米细菌感染,慢性肝病血清中纳米细菌感染率高于健康人。 相似文献
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A constriction injury to the sciatic nerve of the rat produces a painful peripheral neuropathy that is similar to the conditions seen in man. The pathology of the sciatic nerve in these animals was examined at 10 days postinjury, when the abnormal pain sensations are near maximal severity. The nerves were examined with (1) complete series of silver-stained longitudinal sections of pieces of the nerve (3 cm or more) that contained the constriction injury in the center, (2) toluidine blue-stained semithin sections taken at least 1 cm proximal and 1 cm distal to the constriction, and (3) EM sections taken adjacent to those stained with toluidine blue. One centimeter or more proximal to the constriction, both myelinated and unmyelinated axons were all normal. Nearer to the constriction, extensive degeneration of myelinated axons became increasingly common, as did signs of endoneurial edema. Distal to the constriction, the nerve was uniformly edematous and full of myelinic degeneration. There was a profound loss of large myelinated axons and a distinctly less severe loss of small myelinated and unmyelinated axons. These observations show that at 10 days postinjury the constriction produces a partial and differential deafferentation of the sciatic nerve's territory. The absence of degeneration in the nerve 1 cm proximal to the constriction indicates the survival of the primary afferent neurons whose axons are interrupted. 相似文献
7.
Kaija Mikkola Elena Kushnerenko Eino Partanen Silve Serenius-Sirve Jaana Leip?l? Minna Huotilainen Vineta Fellman 《Clinical neurophysiology》2007,118(7):1494-1502
OBJECTIVE: In our previous study, auditory event-related potentials (AERPs) in preterm 1-year-old children had a positive deflection at 150-350 ms that correlated positively with their 2-year neurodevelopmental outcome. In a study of the same subjects at age 5, our aim was to assess AERPs and their relationship to neuropsychological test results. METHODS: Preterm small (SGA, n=13), appropriate for gestational age (AGA, n=15), and control (n=13) children were assessed with an Easy paradigm presenting a large frequency change accompanied with occasional novel sounds, and a Challenging paradigm presenting small frequency and duration changes with a rapid rate. The preterm children underwent neurocognitive tests. RESULTS: Easy paradigm. The P1 response to frequency deviant was smaller and MMN larger in the preterm than in the control children. Challenging paradigm. The P1 response to standard, frequency, and duration deviants was smaller in the preterm than in the control children. The N2 response to frequency deviant was larger in the preterm than in the control children. AGA and SGA children had similar AERPs. The P1, N2, and MMN amplitudes correlated with verbal IQ and NEPSY language subtests. CONCLUSIONS: Small P1 response(s) appears to be typical for preterm children. SIGNIFICANCE: Small P1 response in preterm children may suggest altered primary auditory processing. 相似文献
8.
Bacteriophage PRD1 is an icosahedral dsDNA virus with a diameter of 740 A and an outer protein shell composed of 720 copies of major coat protein P3. Spike complexes at the vertices are composed of a pentameric base (protein P31) and a spike structure (proteins P5 and P2) where the N-terminal region of the trimeric P5 is associated with the base and the C-terminal region of P5 is associated with receptor-binding protein P2. The functionality of proteins P3 and P5 was investigated using insertions and deletions. It was observed that P3 did not tolerate changes whereas P5 tolerated changes much more freely. These properties support the hypothesis that viruses have core structures and functions, which remain stable over time, as well as other elements, responsible for host interactions, which are evolutionally more fluid. The insertional probe used was the apex of exposed loop 4 of group B meningococcal outer membrane protein PorA, a medically important subunit vaccine candidate. It was demonstrated that the epitope could be displayed on the virus surface as part of spike protein P5. 相似文献
9.
Jaana M Ward MM Paré G Wakefield DS 《International journal of medical informatics》2005,74(9):719-731
Despite the growing interest in adopting information technology (IT) in healthcare, the degree of technology sophistication varies among healthcare organizations. Changes in the health care sector and continuous pressure to improve the quality of care have driven the evolution of IT in hospitals. This paper provides an overview of clinical IT sophistication in a sample of U.S. hospitals, and compares clinical IT capacities in this sample with a sample of Canadian hospitals. The instrument used for the comparison measures three clinical dimensions of IT sophistication: functional sophistication, technological sophistication and integration level. Clinical areas that were considered include patient management, patient care activities and clinical support activities. The comparison between hospitals in Iowa and Canada shows differences in clinical IT sophistication between the two settings. Hospitals in Iowa appear to have more technologies but fewer computerized processes and integration of patient management activities. Technological sophistication however, was low in both samples. Our findings confirm the construct validity of the measurement instrument and show initial evidence of its generalizability. More initiatives using the instrument would lead to enhancement in IT assessment tools that can be used for evaluation of IT in relation to patient management and quality outcomes. 相似文献
10.
Veckman V Miettinen M Pirhonen J Sirén J Matikainen S Julkunen I 《Journal of leukocyte biology》2004,75(5):764-771
Dendritic cells (DCs) are the most efficient antigen-presenting cells and thus, have a major role in regulating host immune responses. In the present study, we have analyzed the ability of Gram-positive, pathogenic Streptococcus pyogenes and nonpathogenic Lactobacillus rhamnosus to induce the maturation of human monocyte-derived DCs. Stimulation of DCs with S. pyogenes resulted in strong expression of DC costimulatory molecules CD80, CD83, and CD86 accompanied with a T helper cell type 1 (Th1) cytokine and chemokine response. S. pyogenes also induced interleukin (IL)-2 and IL-12 production at mRNA and protein levels. In addition, IL-23 and IL-27 subunits p40, p19, p28, and EBI3 were induced at mRNA level. In contrast, L. rhamnosus-stimulated DCs showed only moderate expression of costimulatory molecules and produced low levels of cytokines and chemokines. Furthermore, no production of IL-2 or IL-12 family cytokines was detected. Bacteria-induced DC maturation and especially cytokine and chemokine production were reduced when bacteria were heat-inactivated. Our results show that human monocyte-derived DCs respond differently to different Gram-positive bacteria. Although pathogenic S. pyogenes induced a strong Th1-type response, stimulation with nonpathogenic L. rhamnosus resulted in development of semi-mature DCs characterized by moderate expression of costimulatory molecules and low cytokine production. 相似文献