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61.
R A Washburn T C Cook R E LaPorte 《The Journal of sports medicine and physical fitness》1989,29(3):279-284
Thirty-five male United States postal carriers, mean age (+/-SD) 46.1 +/- 11.4 years, mean distance walked on the job 5.3 +/- 3.3 miles day-1, participated in this study to determine the efficacy of two movement sensors for the assessment of daily physical activity. Subjects wore both a Large Scale Integrated Activity Monitor (LSI) and a Caltrac portable accelerometer on a belt for 3 days (2 work days, 1 non-work day) for 2 separate trials separated by a 3 month interval. Both monitors indicated similar mean levels of physical activity over the 2 work days with a significant decrease on the non-work day. Test-retest reliability within one trial over the 2 work days (LSI, r = 0.64; Caltrac, r = 0.58) and and between 2 trials (LSI, r = 0.58, Caltrac, r = 0.57), were similar for both monitors. The mean values for the LSI and Caltrac over the 2 trials were highly related (r = 0.75). Analysis of variance indicated a high percentage of the total variance in physical activity was accounted for by interindividual differences for both monitors (LSI = 77.4%, Caltrac = 77.7%). These results suggest that both the LSI and the Caltrac provide a reliable index of physical activity and can detect inter-individual differences in activity level in occupationally active individuals. 相似文献
62.
Cyclosporin nephrotoxicity in heart and lung transplant patients 总被引:1,自引:0,他引:1
Griffiths MH; Crowe AV; Papadaki L; Banner NR; Yacoub MH; Thompson FD; Neild GH 《QJM : monthly journal of the Association of Physicians》1996,89(10):751-763
Twenty-two patients with heart, lung or heart and lung transplants
maintained on cyclosporin for periods ranging from 3 months to 10 years
developed renal insufficiency which was investigated by renal biopsy. The
histopathological changes were: (i) severe vascular and glomerular damage
due to thrombotic microangiopathy (TM); (ii) a form of focal segmental
glomerulosclerosis (FSGS); (iii) glomerular ischaemia. Rather than being
separate entities, these changes appeared to represent a spectrum of
pathology, some biopsies showing all three forms of glomerular injury. In
all cases the glomerular changes were accompanied by arteriolar and
arterial pathology, and we identified novel ultrastructural changes in the
arteriolar endothelial basal lamina. Tubular atrophy was a consistent
feature, the severity of which reflected the severity of the glomerular
sclerosis, and which appeared to be a consequence of glomerular loss. Our
findings are consistent with the nephrotoxic effects of cyclosporin being
mediated chiefly via damage to preglomerular vessels and glomerular
capillary endothelium. From an analysis of the clinical aspects of these
cases, the effects of cyclosporin appear to be to some extent
idiosyncratic, and therefore not entirely preventable, but strict
monitoring of blood cyclosporin levels is essential to minimize the risk of
permanent renal damage. Monitoring urinary protein in addition to plasma
creatinine may detect the onset of FSGS, as proteinuria precedes creatinine
elevation.
相似文献
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67.
目的研究两个Eph家族分子,EphA5受体及其配体ephrin—A5,在脊髓发育过程中的表达方式。方法β-半乳糖苷酶基因敲入小鼠和配体亲和探针分析受体的表达,两种不同的亲和探针分析配体的表达,基因敲除小鼠作为对照。结果在发育过程中,EphA5表达于脊髓腹侧,而ephrin—A5表达于脊髓背侧。结论EphA5和ephrin—A5在多个脊髓发育阶段都有表达,他们可能在脊髓背腹侧组织结构的建立过程中发挥重要作用。 相似文献
68.
Sidi A. Bencherif Abiraman Srinivasan Jeffrey A. Sheehan Lynn M. Walker Chakicherla Gayathri Roberto Gil Jeffrey O. Hollinger Krzysztof Matyjaszewski Newell R. Washburn 《Acta biomaterialia》2009,5(6):1872-1883
A series of resorbable poly(ethylene glycol)-co-poly(glycolic acid) (PEG-co-PGA, 4KG5) macromonomers have been synthesized with the chemistries from three different photopolymerizable end-groups (acrylates, methacrylates and urethane methacrylates). The aim of the study is to examine the effects of the chemistry of the cross-linker group on the properties of photocross-linked hydrogels. 4KG5 hydrogels were prepared by photopolymerization with high vinyl group conversion as confirmed by 1H nuclear magnetic resonance spectrometry using a 1D diffusion-ordered spectrometry pulse sequence. Our study reveals that the nature of end-groups in a moderately amphiphilic polymer can adjust the distribution and size of the micellar configuration in water, leading to changes in the macroscopic structure of hydrogels. By varying the chemistry of the cross-linker group (diacrylates (DA), dimethacrylates (DM) and urethane dimethacrylates (UDM)), we determined that the hydrophobicity of a single core polymer consisting of poly(glycolic acid) could be fine-tuned, leading to significant variations in the mechanical, swelling and degradation properties of the gels. In addition, the effects of cross-linker chemistry on cytotoxicity and proliferation were examined. Cytotoxicity assays showed that the three types of hydrogels (4KG5 DA, DM and UDM) were biocompatible and the introduction of RGD ligand enhanced cell adhesion. However, differences in gel properties and stability differentially affected the spreading and proliferation of myoblast C2C12 cells. 相似文献
69.
70.
Abram KM Choe JY Washburn JJ Teplin LA King DC Dulcan MK 《Journal of the American Academy of Child and Adolescent Psychiatry》2008,47(3):291-300
OBJECTIVE: To examine suicidal ideation, suicide attempts, lethality of suicide attempts, and the relationship between psychiatric disorder and recent attempts in newly detained juveniles. METHOD: The sample included 1,829 juveniles, ages 10 to 18 years, sampled after intake to a detention center in Chicago. Interviewers administered the Diagnostic Interview Schedule for Children to assess for thoughts of death, suicidal ideation, suicide plans, lifetime suicide attempts, number of attempts, age at first attempt, attempts within the past 6 months, method of suicide attempts, and psychiatric disorder. RESULTS: More than one third of juvenile detainees and nearly half of females had felt hopeless or thought about death in the 6 months before detention. Approximately 1 in 10 (10.3%, 95% confidence interval: 7.7%-12.8%) juvenile detainees had thought about committing suicide in the past 6 months, and 1 in 10 (11.0%, 95% confidence interval: 8.3%-13.7%) had ever attempted suicide. Recent suicide attempts were most prevalent in females and youths with major depression and generalized anxiety disorder. CONCLUSIONS: Fewer than half of detainees with recent thoughts of suicide had told anyone about their ideation. Identifying youths at risk for suicide, especially those suffering from depressive and anxiety disorders, is a crucial step in preventing suicide. 相似文献