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301.
Total hip replacement due to osteoarthritis: the importance of age,obesity, and other modifiable risk factors 总被引:12,自引:0,他引:12
Karlson EW Mandl LA Aweh GN Sangha O Liang MH Grodstein F 《The American journal of medicine》2003,114(2):93-98
We studied whether several modifiable factors were associated with the risk of total hip replacement due to hip osteoarthritis among women.We identified 568 women from the Nurses' Health Study who reported total hip replacement due to primary hip osteoarthritis on questionnaires from 1990 to 1996, using a validated algorithm. The relation of potential risk factors, such as age, body mass index, physical activity, smoking, alcohol intake, and hormone use, to hip replacement was assessed using pooled logistic regression models.Higher body mass index was associated with an increased risk of hip replacement due to osteoarthritis (P for trend = 0.0001). Compared with women in the lowest category of body mass index (<22 kg/m(2)), those in the highest category of body mass index (> or =35 kg/m(2)) had a twofold increased risk (95% confidence interval [CI]: 1.4 to 2.8), whereas those in the highest category of body mass index at age 18 years had more than a fivefold increased risk (95% CI: 2.5 to 10.7). Age also had a positive association; women aged > or =70 years were nine times more likely to have hip replacement than those aged <55 years (95% CI: 5.4 to 13.9). Recreational physical activity, smoking, alcohol use, and postmenopausal hormone use were not associated with an increased risk of hip replacement.In the Nurses' Health Study, higher body mass index and older age significantly increased the risk of total hip replacement due to osteoarthritis. Part of this risk appeared to be established early in life. 相似文献
302.
Bellavance M Béland MJ van Doesburg NH Paquet M Ducharme FM Cloutier A 《Cardiology in the young》2004,14(6):608-614
The implementation committee of the Quebec Child Telehealth Network was formed in 1997, with a mandate to build a network dedicated to the diagnosis of congenital cardiac disease via telemedicine. We devised criterions for selection to determine which peripheral centres would be linked by telemedicine to the university-based services for paediatric cardiology provided in the Canadian Province of Quebec. The criterions included: distance from a university centre, number of births per year, and presence of an already-established outreach clinic for paediatric cardiology. The Quebec Network became operational in 2000, and was composed of 32 peripheral centres and 4 university centres. A total of 363 transmissions of echocardiograms occurred over a 3-year period from January 2000 to December 2002. Peripheral centres located at a distance greater than 100 kilometres from a university centre were 8.5 times more likely to use the network. Criterions other than distance did not influence whether or not a peripheral centre used the network. Cardiac abnormalities were identified in almost two-thirds of the transmissions. The use of the Quebec Network resulted in the avoidance of transfers or clinic visits to university hospitals in seven-tenths of cases. We conclude that distance greater than 100 kilometres from a centre offering subspecialty services in paediatric cardiology is the most important criterion for choosing the peripheral centres that are most likely to use a telehealth network. In its first three years of operation, the telehealth network had a major impact on the delivery of paediatric cardiac care, improving access to subspecialty services across the province. 相似文献
303.
Summary Insulin release induced by 3-phenylpyruvate in rat pancreatic islets was unaffected by L-norleucine, L-valine, L-alanine and
L-asparagine, but potentiated by L-glutamine, glycine and L-serine. The latter two amino acids also enhanced insulin secretion
evoked by the combination of 3-phenylpyruvate and L-glutamine. Since 3-phenylpyruvate is known to stimulate insulin release
by acting as a transamination partner and facilitating the catabolism of endogenous amino acids, the present findings suggest
that the secretory efficiency of such a biochemical sequence depends upon the subcellular location of the transamination reaction
and upon the interference of 3-phenylpyruvate with the transport of 2-keto acids into mitochondria. 相似文献
304.
305.
306.
Resilience, exhibiting intact psychological functioning despite exposure to trauma, is one perspective as to why some people who are exposed to trauma do not develop symptoms. This study examines the prisoner of war experience to expand our understanding of this phenomenon in extreme cases of trauma such as prolonged captivity, malnourishment, and physical and psychological torture. The study examined the United States' longest detained American prisoners of war, those held in Vietnam in the 1960s through early 1970s. A logistic regression analysis using resilience, defined as never receiving any psychiatric diagnosis over a 37-year follow-up period, as the outcome was performed (n = 224 with complete data). Six variables showing at least small effects emerged: officer/enlisted status, age at time of capture, length of solitary confinement, low antisocial/psychopathic personality traits, low posttraumatic stress symptoms following repatriation, and optimism. Odds ratios (ORs) and confidence intervals (CIs) confirmed the significance and relative strength of these variables, with a range from OR = 0.54, 95% CI [0.13, 2.29] to OR = 1.11, 95% CI [1.04, 1.17]. When all variables were examined continuously and categorically, dispositional optimism was the strongest variable, accounting for 17%, continuously, and 14%, categorically. We discuss optimism as a protective factor for confronting trauma and the possibility of training to increase it. 相似文献
307.
Marsha D. Marcus Kathryn Hirst Francine Kaufman Gary D. Foster Tom Baranowski 《Current diabetes reports》2013,13(1):63-71
The HEALTHY trial was designed to take a primary prevention approach to risk factors for type 2 diabetes in youth, primarily obesity. The study involved over 6,000 students at 42 middle schools across the U.S. Half received an integrated intervention program of components addressing the school food environment, physical education, lifestyle behaviors, and promotional messaging. The intervention was designed to be more comprehensive than previous efforts, and the research was amply funded. Although the primary objective of reducing the percentage of overweight and obesity in schools that received the intervention program, as compared with control schools, was not obtained, key secondary outcomes indicated an intervention effect. In retrospect, senior investigators involved in the study’s design, conduct, and analysis discuss weaknesses and strengths and offer recommendations for future research efforts that address prevention of childhood obesity from a public health perspective. 相似文献
308.
309.
John B. Buse Francine R. Kaufman Barbara Linder Kathryn Hirst Laure El ghormli Steven Willi for the HEALTHY Study Group 《Diabetes care》2013,36(2):429-435
OBJECTIVE
To characterize middle-school students from the HEALTHY study with glycemic abnormalities, specifically high-risk hemoglobin A1c (A1C) (hrA1C; A1C = 5.7–6.4%) and impaired fasting glucose (IFG; fasting plasma glucose [FPG] = 100–125 mg/dL).RESEARCH DESIGN AND METHODS
History was collected by self-report, physical measurement was collected by trained study staff, and fasting blood was drawn by trained phlebotomists and analyzed centrally.RESULTS
At baseline, among 3,980 sixth graders, 128 (3.2%) had hrA1C and 635 (16.0%) had IFG. Compared with A1C <5.7%, hrA1C was associated with non-Hispanic black race/ethnicity, family history of diabetes, and higher measurements of BMI, waist circumference, and fasting insulin. Compared with FPG <100 mg/dL, IFG was associated with Hispanic ethnicity; increased BMI, waist circumference, and fasting insulin; higher frequency of high blood pressure; and higher mean triglycerides. Two years later, children with hrA1C persisted as hrA1C in 59.4%, and one child (0.8%) developed A1C ≥6.5%; children with IFG persisted with IFG in 46.9%, and seven children (1.1%) developed FPG ≥126 mg/dL. Those with hrA1C compared with IFG had a higher BMI in sixth grade, which persisted to eighth grade.CONCLUSIONS
In the HEALTHY study cohort, hrA1C and IFG define different groups of youth with differentially increased diabetes risk markers. IFG is approximately fivefold more common, but hrA1C is more persistent over time. Optimal screening strategies for diabetes in youth remain unresolved.The HEALTHY study was conducted to determine if a middle-school–based intervention program could reduce risk factors for type 2 diabetes in a multiethnic cohort of students (1,2). The primary outcome for the study was a change in the percent of students with a BMI ≥85th percentile (combined prevalence of overweight and obesity adjusted for sex and age), which decreased by ∼4% in both intervention and control schools (P = NS) from sixth to eighth grades; however, among the sample of students who were overweight or obese (≥85th percentile) in sixth grade (50% of the sample), intervention schools showed greater reductions in the prevalence of obesity (BMI ≥95th percentile) than control schools, suggesting that the intervention had an effect on obesity rather than on overweight (3).Among other risk factors for type 2 diabetes, hemoglobin A1c (A1C) and fasting plasma glucose (FPG) were collected at baseline and the end of study. It has been suggested that A1C can identify adults with diabetes and prediabetes (4,5). There are few prospective data regarding glycemic risk markers in diverse populations of youth. HEALTHY data were used to determine the distribution, durability, and association of high-risk A1C (hrA1C) with other diabetes risk factors in comparison with impaired fasting glucose (IFG) to inform decision making regarding screening and prevention strategies in youth. 相似文献310.
Absence of Lamellar Bodies with Accumulation of Dense Bodies Characterizes a Novel Form of Congenital Surfactant Defect 总被引:1,自引:0,他引:1
A. Francine Tryka Susan E. Wert Jon E. Mazursky Robert W. Arrington Lawrence M. Nogee 《Pediatric and developmental pathology》2000,3(4):335-345
Two female sibling full-term newborns developed respiratory distress shortly after birth, which progressed to respiratory failure. Tracheal lavage demonstrated presence of surfactant protein A (SP-A), but little surfactant protein B (SP-B), without aberrant surfactant protein C (SP-C). On a lung biopsy performed in both infants, prominent type II pneumocyte hyperplasia was evident. Through ultrastructural examination an absence of normally formed lamellar bodies was determined, with numerous irregular electron dense bodies within the type II pneumocytes. These electron dense bodies could also be identified in the alveolar spaces and alveolar macrophages. No alveolar tubular myelin was present. Abnormally high immunoreactivity for surfactant proteins SP-A, proSP-B, SP-B, and proSP-C was demonstrated by light microscopy. Presence of incompletely processed immunopositive proSP-B, but not proSP-C was observed in the alveolar lumina. No mutations in either the SP-B or SP-C gene were identified by sequence analysis of amplified cDNA. We conclude that these siblings exhibit an inherited surfactant deficiency characterized by abnormal accumulations of surfactant proteins within the pneumocytes. This abnormal accumulation may be due to a primary secretory defect, a defect in surfactant phospholipids, or an abnormal interaction between the phospholipids and surfactant proteins. Received November 17, 1998; accepted August 19, 1999. 相似文献