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101.
Dhondt AA Altizer S Cooch EG Davis AK Dobson A Driscoll MJ Hartup BK Hawley DM Hochachka WM Hosseini PR Jennelle CS Kollias GV Ley DH Swarthout EC Sydenstricker KV 《Acta tropica》2005,94(1):77-93
In early 1994, a novel strain of Mycoplasma gallisepticum (MG)--a poultry pathogen with a world-wide distribution--emerged in wild house finches and within 3 years had reached epidemic proportions across their eastern North American range. The ensuing epizootic resulted in a rapid decline of the host population coupled with considerable seasonal fluctuations in prevalence. To understand the dynamics of this disease system, a multi-disciplinary team composed of biologists, veterinarians, microbiologists and mathematical modelers set forth to determine factors driving and influenced by this host-pathogen system. On a broad geographic scale, volunteer observers ("citizen scientists") collected and reported data used for calculating both host abundance and disease prevalence. The scale at which this monitoring initiative was conducted is unprecedented and it has been an invaluable source of data for researchers at the Cornell Laboratory of Ornithology to track the spread and magnitude of disease both spatially and temporally. At a finer scale, localized and intensive field studies provided data used to quantify the effects of disease on host demographic parameters via capture-mark-recapture modeling, effects of host behavior on disease and vice-versa, and the biological and genetic profiles of birds with known phenotypic characteristics. To balance the field-based component of the study, experiments were conducted with finches held in captivity to describe and quantify the effects of experimental infections on hosts in both individual and social settings. The confluence of these various elements of the investigation provided the foundation for construction of a general compartmentalized epidemiological model of the dynamics of the house finch-MG system. This paper serves several purposes including (i) a basic review of the pathogen, host, and epidemic cycle; (ii) an explanation of our research strategy; (iii) a basic review of results from the diverse multi-disciplinary approaches employed; and (iv) pertinent questions relevant to this and other wildlife disease studies that require further investigation. 相似文献
102.
Parental stress and burden following traumatic brain injury amongst children and adolescents 总被引:2,自引:0,他引:2
Primary objectives: To assess parental stress following paediatric traumatic brain injury (TBI), and examine the relationship between self-reported problems, parental stress and general health.
Research design: Parents of 97 children admitted with a TBI (49 mild, 19 moderate, 29 severe) to North Staffordshire National Health Service Trust, and parents of 31 uninjured children were interviewed and assessed.
Methods and procedures: Structured interviews were carried out with families, and parents assessed on the Parenting Stress Index (PSI/SF) and General Health Questionnaire (GHQ-12) at recruitment, and repeated 12 months later.
Main outcomes and results: Forty parents (41.2%) of children with TBI exhibited clinically significant stress. Regardless of injury severity, parents of injured children suffered greater stress than control parents as measured by the PSI/SF (p = 0.001). There was a highly significant relationship between number of problems reported and level of parental stress (p = 0.001). Financial burden was related to severity of TBI. At follow-up, one third of parents of children with severe TBI scored ≥18 on the GHQ-12, signifying poor psychological health.
Conclusions: The parents of a child with serious TBI should be screened for abnormal levels of stress. Parental stress and family burden may be alleviated by improved information, follow-up and support. 相似文献
Research design: Parents of 97 children admitted with a TBI (49 mild, 19 moderate, 29 severe) to North Staffordshire National Health Service Trust, and parents of 31 uninjured children were interviewed and assessed.
Methods and procedures: Structured interviews were carried out with families, and parents assessed on the Parenting Stress Index (PSI/SF) and General Health Questionnaire (GHQ-12) at recruitment, and repeated 12 months later.
Main outcomes and results: Forty parents (41.2%) of children with TBI exhibited clinically significant stress. Regardless of injury severity, parents of injured children suffered greater stress than control parents as measured by the PSI/SF (p = 0.001). There was a highly significant relationship between number of problems reported and level of parental stress (p = 0.001). Financial burden was related to severity of TBI. At follow-up, one third of parents of children with severe TBI scored ≥18 on the GHQ-12, signifying poor psychological health.
Conclusions: The parents of a child with serious TBI should be screened for abnormal levels of stress. Parental stress and family burden may be alleviated by improved information, follow-up and support. 相似文献
103.
104.
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
105.
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
106.
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
107.
Foreign body removal has been developed as a routine radiology department service. Techniques, indications and hazards are described. 相似文献
108.
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
109.
110.
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