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71.
72.
Our present scientific knowledge of the effects of specific training interventions undertaken by professional cyclists on selected adaptive responses in skeletal muscle and their consequences for improving endurance performance is limited: sport scientists have found it difficult to persuade elite cyclists to experiment with their training regimens and access to muscle and blood samples from these athletes is sparse. Owing to the lack of scientific study we present a theoretical model of some of the major training-induced adaptations in skeletal muscle that are likely to determine performance capacity in elite cyclists. The model includes, but is not limited to, skeletal muscle morphology, acid-base status and fuel supply. A working premise is that the training-induced changes in skeletal muscle resulting from the high-volume, high-intensity training undertaken by elite cyclists is at least partially responsible for the observed improvements in performance. Using experimental data we provide evidence to support the model. 相似文献
73.
McElroy PD ter Kuile FO Lal AA Bloland PB Hawley WA Oloo AJ Monto AS Meshnick SR Nahlen BL 《The American journal of tropical medicine and hygiene》2000,62(4):504-512
The relative importance of acute high-density versus persistent low-density Plasmodium falciparum parasitemia in contributing to the public health problem of malarial anemia remains unclear. The Asembo Bay Cohort Project in western Kenya collected monthly hemoglobin (Hb) and parasitologic measurements and biweekly assessments of antimalarial drug use among 942 singleton live births between 1992 and 1996. A mixed-model analysis appropriate for repeated measures data was used to study how time-varying parasitemia and antimalarial drug exposures influenced mean Hb profiles. Incidence of World Health Organization-defined severe malarial anemia was 28.1 per 1,000 person-years. Among children aged less than 24 months, concurrent parasitemia was significantly associated with lower mean Hb, especially when compared to children with no concurrent parasitemia. Increased densities of the 90-day history of parasitemia preceding Hb measurement was more strongly associated with mean Hb levels than concurrent parasitemia density. While the highest quartile of 90-day parasitemia history was associated with lowest mean Hb levels, children in the lowest 90-day exposure quartile still experienced significantly lower Hb levels when compared to children who remained parasitemia-free for the same 90-day period. The results highlight the importance of collecting and analyzing longitudinal Hb and parasitologic data when studying the natural history of malarial anemia. 相似文献
74.
Berg ML Crosby RD Wonderlich SA Hawley D 《The International journal of eating disorders》2000,28(2):148-154
OBJECTIVE: Examine the relationship between temperament variables and perceptions of nonshared environment as they relate to bulimia nervosa. METHOD: Fifty-seven adult women completed the Tridimensional Personality Questionnaire and the Sibling Inventory of Differential Experience. These measures provided assessments of frequently studied temperament traits as well as nonshared environmental factors believed to be associated with psychopathology and temperament. RESULTS: Bulimic subjects showed higher levels of harm avoidance than did control subjects. Also, bulimic subjects perceived their fathers as less affectionate and more controlling than control subjects. Among bulimics, high levels of harm avoidance were associated with high levels of maternal affection and low levels of maternal control. Similarly, among bulimics, high levels of novelty seeking were more likely to be associated with decreased paternal control than was true for control subjects. DISCUSSION: These findings highlight the possible relationship between particular temperamental variables and associated family responses in bulimia nervosa. 相似文献
75.
JN HANNA WL SEXTON JL FAOAGALI PJ BUDA ML KENNETT KA BRUSSEN 《Journal of paediatrics and child health》1995,31(4):345-349
Objective: To determine the immunity to hepatitis B, poliomyelitis and measles in fully vaccinated Aboriginal and Torres Strait Island children in north Queensland.
Methodology: A cross-sectional survey of immunity in a sample of children; 101 fully vaccinated Aboriginal and Torres Strait Island children, with a median age of 24.5 months, from 10 communities in North Queensland participated in this study. The main outcome measures were the prevalence of adequate antibody levels against hepatitis B, poliomyelitis and measles.
Results: Only 54% (95% Cl 44–63%) of the children had adequate immunity (10 m iu/mL) to hepatitis B, and one child had been infected despite vaccination. Although all the children (95% Cl 96–100%) had adequate immunity (i.e. neutralizing antibodies at a dilution of 1:8) to poliovirus 2, only 93% (95% Cl 86–96%) and 60% (95% Cl 50–69%) had adequate immunity to polioviruses 1 and 3, respectively. Nearly all (96%; 95% Cl 90–98%) of the children had adequate immunity (i.e. detectable IgG antibody) to measles.
Conclusions: Although a relatively low proportion of the children had adequate antibody levels against hepatitis B the clinical significance of this observation is uncertain. Further studies are needed to determine whether fully vaccinated Torres Strait Island children have been adequately protected and whether they require a booster dose of hepatitis B vaccine. A substantial proportion of fully vaccinated Aboriginal and Torres Strait Island children are inadequately protected against poliomyelitis, and therefore any such child with acute flaccid paralysis should be investigated fully for poliomyelitis. Vaccinated Aboriginal and Torres Strait Island children are well protected against measles, as are other Australian children. 相似文献
Methodology: A cross-sectional survey of immunity in a sample of children; 101 fully vaccinated Aboriginal and Torres Strait Island children, with a median age of 24.5 months, from 10 communities in North Queensland participated in this study. The main outcome measures were the prevalence of adequate antibody levels against hepatitis B, poliomyelitis and measles.
Results: Only 54% (95% Cl 44–63%) of the children had adequate immunity (10 m iu/mL) to hepatitis B, and one child had been infected despite vaccination. Although all the children (95% Cl 96–100%) had adequate immunity (i.e. neutralizing antibodies at a dilution of 1:8) to poliovirus 2, only 93% (95% Cl 86–96%) and 60% (95% Cl 50–69%) had adequate immunity to polioviruses 1 and 3, respectively. Nearly all (96%; 95% Cl 90–98%) of the children had adequate immunity (i.e. detectable IgG antibody) to measles.
Conclusions: Although a relatively low proportion of the children had adequate antibody levels against hepatitis B the clinical significance of this observation is uncertain. Further studies are needed to determine whether fully vaccinated Torres Strait Island children have been adequately protected and whether they require a booster dose of hepatitis B vaccine. A substantial proportion of fully vaccinated Aboriginal and Torres Strait Island children are inadequately protected against poliomyelitis, and therefore any such child with acute flaccid paralysis should be investigated fully for poliomyelitis. Vaccinated Aboriginal and Torres Strait Island children are well protected against measles, as are other Australian children. 相似文献
76.
Children's brain injury: a postal follow-up of 525 children from one health region in the UK 总被引:6,自引:0,他引:6
Primary objectives : To follow-up a population of children admitted to one Hospital Trust with traumatic brain injury (TBI), and compare outcomes following mild TBI with outcomes following moderate or severe TBI.
Research design : Population-based postal questionnaire survey.
Methods and procedures : Questionnaires were mailed to parents of all 974 surviving children on a register of paediatric TBI admissions, 525 completed questionnaires were returned (56.2%). Most children (419) had suffered mild TBI, 57 moderate, and 49 severe.
Main outcomes and results : Thirty per cent of parents received no information on post-injury symptoms, and clinical follow-up was limited. Statistically significant differences were observed between mild and moderate/severe groups for cognitive, social, emotional, and mobility problems. Nevertheless, ~20% of the mild group suffered from poor concentration, personality change and educational problems post-injury. Few schools (20%) made special provision for children returning after injury.
Conclusions : Children can have long-lasting and wide-ranging sequelae following TBI. Information should be routinely given to parents and schools after brain injury. 相似文献
Research design : Population-based postal questionnaire survey.
Methods and procedures : Questionnaires were mailed to parents of all 974 surviving children on a register of paediatric TBI admissions, 525 completed questionnaires were returned (56.2%). Most children (419) had suffered mild TBI, 57 moderate, and 49 severe.
Main outcomes and results : Thirty per cent of parents received no information on post-injury symptoms, and clinical follow-up was limited. Statistically significant differences were observed between mild and moderate/severe groups for cognitive, social, emotional, and mobility problems. Nevertheless, ~20% of the mild group suffered from poor concentration, personality change and educational problems post-injury. Few schools (20%) made special provision for children returning after injury.
Conclusions : Children can have long-lasting and wide-ranging sequelae following TBI. Information should be routinely given to parents and schools after brain injury. 相似文献
77.
78.
Safford M Eaton L Hawley G Brimacombe M Rajan M Li H Pogach L 《Archives of internal medicine》2003,163(8):922-928
BACKGROUND: People with diabetes are at high risk for cardiovascular events regardless of known heart disease. Physicians may underrecognize the excess cardiovascular risk conferred by diabetes alone, without a recent cardiovascular event. Other disparities in the receipt of lipid-lowering medications (LLMs) may exist. METHODS: We studied veterans with diabetes in fiscal years 1998 and 1999 cross-sectionally. We used administrative data (demographic information, International Classification of Diseases, Ninth Revision [ICD-9] codes, utilization information, medications, and laboratory tests) to evaluate associations between use of LLMs and age, ethnicity, sex, marital status, Charlson Index, heart disease ICD-9 codes, oral agents and insulin, hospitalization status, and low-density lipoprotein cholesterol levels. We constructed separate logistic regression models to evaluate associations between low-density lipoprotein cholesterol and similar predictor variables. RESULTS: Odds ratios were similar in both years. For fiscal year 1999, patients without recent ICD-9 codes in their administrative data indicating heart disease were 0.35 times less likely to be given LLMs than those with such codes. Individuals older than 75 years were 0.65 times less likely to be given LLMs than those younger than 65 years. African Americans were 0.72 times less likely than whites to be given LLMs. In fiscal years 1999 and 1998, 27% and 36% of individuals given LLMs had low-density lipoprotein cholesterol levels higher than 130 mg/dL (3.37 mmol/L). CONCLUSIONS: Veterans with diabetes but no recently coded heart disease, older individuals, and African Americans could benefit from programs targeted to introduce LLMs. Up to one third of individuals given LLMs remained above the target level of 130 mg/dL for low-density lipoprotein cholesterol. 相似文献
79.
Selectins influence thrombosis in a mouse model of experimental deep venous thrombosis 总被引:8,自引:0,他引:8
Myers D Farris D Hawley A Wrobleski S Chapman A Stoolman L Knibbs R Strieter R Wakefield T 《The Journal of surgical research》2002,108(2):212-221
BACKGROUND: This study characterizes venous thrombosis in the mouse and examines the important role that the adhesion molecules P-selectin and E-selectin and the anti-inflammatory cytokine interleukin-10 (IL-10) play in the thrombotic process. MATERIALS AND METHODS: C57BL/6 (wild-type) mice in a natural history protocol (Phase I) and gene-targeted (KO) mice for P-selectin, E-selectin, P/E-selectin, and IL-10 in a follow-up protocol (Phase II) were studied. Inferior vena caval thrombosis was produced by ligation just below the renal veins, and mice were sacrificed and evaluated at various time points up to 12 days later. RESULTS: Phase I: A significant increase in neutrophils on day 2 and in monocytes on day 6 postthrombosis was found in ligated vs sham animals. An associated significant increase in vein wall P-selectin mRNA (6 h, day 2) and an increase in protein (6 h through day 6) were found, while E-selectin mRNA was significantly increased (day 2 through day 6), with a smaller increase in E-selectin protein. IL-10 mRNA increased significantly later (day 2 through day 9), with the values increasing progressively. A positive correlation existed (r = 0.77) between neutrophils and thrombosis at day 2. PHASE II: The E-selectin and P/E-selectin double-KO mice showed the least thrombus at day 2 vs wild-type clotted mice, P < 0.01. Additionally, P/E-KO mice demonstrated the lowest inflammatory cell extravasation into the vein wall at day 2. CONCLUSIONS: This study demonstrates an acute to chronic inflammatory response in the vein wall associated with venous thrombosis. Inhibition of selectins decreased thrombus formation. 相似文献
80.
Johnson DW Nicol DL Purdie DM Preston JM Brown AM Hawley CM Campbell SB Wall D Griffin AD Isbel NM 《Transplantation》2002,73(7):1158-1163
BACKGROUND: Mycophenolate mofetil (MMF) is a potent immunosuppressive agent that has been shown to be superior to azathioprine in preventing early acute rejection in the general renal transplant population. However, it is uncertain whether these benefits also apply to older renal transplant recipients, who are known to be more susceptible to infectious complications and have considerably lower rates of rejection and immunological graft loss. METHODS: A retrospective analysis was undertaken of all elderly (> or =55 years old) renal transplant recipients who underwent renal transplantation at the Princess Alexandra Hospital (1994-2000) and received either MMF (n=60) or azathioprine (n=55) in combination with prednisolone and cyclosporin. Data were analyzed on an intention-to-treat basis using a multivariate Cox proportional hazards model. RESULTS: The azathioprine- and MMF-treated groups were well matched at baseline with respect to demographic characteristics, end-stage renal failure causes and transplant characteristics. Compared with the MMF cohort, azathioprine-treated patients experienced a shorter time to first rejection [hazard ratio (HR) 4.47, 95% CI 1.53-13.1, P<0.01]. However, azathioprine-treated patients were also less likely to develop opportunistic infections (HR 0.11, 95% CI 0.03-0.41, P=0.001). No differences were observed between the two groups with respect to hospitalization rates, intensive care admissions, hematological complications, or posttransplant malignancies. Actuarial 2-year survival rates for the azathioprine- and MMF-treated patients were 100 and 87%, respectively (P<0.001). The principal cause of death in the MMF cohort was infection. Using a multivariate Cox regression analysis of patient survival, an adjusted hazard ratio of 0.01 (95% CI 0.001-0.08, P=0.001) was calculated in favor of azathioprine. Overall graft survival also tended to be better in patients receiving azathioprine (HR 0.27, 95% CI 0.06-1.33, P=0.11), CONCLUSIONS: In elderly renal transplant recipients, the combination of MMF, cyclosporin, and prednisolone appears to result in a worse outcome compared with the less potent combination of azathioprine, cyclosporin, and prednisolone. Future prospective studies need to specifically evaluate the risk/benefit ratios of newer, more potent immunosuppressive protocols, such as MMF-based regimens, in this important and sizeable patient subgroup. 相似文献