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41.
The National Youth Sports Program (NYSP) is an annual event sponsored by the National Collegiate Athletic Association that provides structured sports and enrichment programs to youth of low socioeconomic status. As part of the program, youths undergo a free medical examination that uses a physical examination checklist but does not include a section on medical history. To determine what additional information a medical history would provide, a history form was used in conjunction with the regular preparticipation examination for participants in the 1996 NYSP at the North Carolina Agricultural and Technical State University. The history form provided information such as family history of sudden death, personal history of asthma or bone injury, and whether participants took medications or used corrective lenses. Seventy-nine percent of the completed history forms documented a positive response to at least one question. Of these, only 5% had physical findings on examination. Conversely, 15% of participants had physical findings that were not reported on the history form. Because much of what is discovered by a medical history often is not found on physical examination and because history information can be used to prevent the occurrence of an accident or illness, this study suggests that the use of such a form is beneficial in providing a more comprehensive screening. 相似文献
42.
Antigenic heterogeneity of the hepatitis C virus NS4 protein as modeled with synthetic peptides 总被引:1,自引:0,他引:1
The effect of sequence heterogeneity on the immunologic properties of two strong antigenic regions of the hepatitis C virus (HCV) NS4 protein was studied by using a set of 443 overlapping 20-mer synthetic peptides. One antigenic region comprising the cleavage site between NS4a and NS4b (region 5-1-1) was modeled with peptides derived from 73 different known sequences, representing HCV genotypes 1-6. The other antigenic region, designated region 59 and located at the C-terminus of the NS4b protein, was modeled with peptides from 7 known sequences representing genotypes 1-3. All peptides were tested for antigenic reactivity by enzyme immunoassay with a panel of anti-HCV-positive serum specimens representing genotypes 1-5. The data demonstrated that immunoreactive peptides fell into two groups. One group, represented by N-terminal peptides, demonstrated genotype-independent immunoreactivity; the other group, from the central part of region 5-1-1, showed strict genotype specificity. Nineteen peptides from the genotype-independent group strongly immunoreacted with a wide range of serum samples containing antibodies to all 5 HCV genotypes. Twenty-five peptides from the genotype-specific group were found to strongly react with serum containing antibodies only to the genotype from which the peptides were derived. Similar to the N-terminal part of region 5-1-1, peptides derived from region 59 did not show genotype-specific immunoreactivity. Some peptides derived from the central part of region 59 showed very strong and broad antigenic reactivity. Thus, after examining two antigenic regions of the NS4 protein, we identified short sequences that can be used for the efficient detection of either genotype-independent or genotype-specific HCV antibodies. 相似文献
43.
A community outbreak of Legionnaires' disease linked to hospital cooling towers: an epidemiological method to calculate dose of exposure. 总被引:1,自引:0,他引:1
C M Brown P J Nuorti R F Breiman A L Hathcock B S Fields H B Lipman G C Llewellyn J Hofmann M Cetron 《International journal of epidemiology》1999,28(2):353-359
BACKGROUND: From July to September 1994, 29 cases of community-acquired Legionnaires' disease (LD) were reported in Delaware. The authors conducted an investigation to a) identify the source of the outbreak and risk factors for developing Legionella pneumophila serogroup 1 (Lp-1) pneumonia and b) evaluate the risk associated with the components of cumulative exposure to the source (i.e. distance from the source, frequency of exposure, and duration of exposure). METHODS: A case-control study matched 21 patients to three controls per case by known risk factors for acquiring LD. Controls were selected from patients who attended the same clinic as the respective case-patients. Water samples taken at the hospital, from eight nearby cooling towers, and from four of the patient's homes were cultured for Legionella. Isolates were subtyped using monoclonal antibody (Mab) analysis and arbitrarily primed polymerase chain reaction (AP-PCR). RESULTS: Eleven (52%) of 21 case-patients worked at or visited the hospital compared with 17 (27%) of 63 controls (OR 5.0, 95% CI : 1.1-29). For those who lived, worked, or visited within 4 square miles of the hospital, the risk of illness decreased by 20% for each 0.10 mile from the hospital; it increased by 80% for each visit to the hospital; and it increased by 8% for each hour spent within 0.125 miles of the hospital. Lp-1 was isolated from three patients and both hospital cooling towers. Based on laboratory results no other samples contained Lp-1. The clinical and main-tower isolates all demonstrated Mab pattern 1,2,5,6. AP-PCR matched the main-tower samples with those from two case-patients. CONCLUSION: The results of our investigation suggested that the hospital cooling towers were the source of a community outbreak of LD. Increasing proximity to and frequency of exposure to the towers increased the risk of LD. New guidelines for cooling tower maintenance are needed. Knowing the location of cooling towers could facilitate maintenance inspections and outbreak investigations. 相似文献
44.
This paper examines the impressions and experiences of administrators who manage Community Health Centers (CHCs) in Region VI, US Department of Health and Human Services, with the goal of identifying leadership skills and intrinsic values that are needed to run integrated service delivery sites. As the delivery of healthcare service shifts to health promotion and disease prevention, Community Health Centers are well positioned to assume major roles in this transition. However, some CHC administrators may need additional skills in order to address the changing healthcare environment. A survey of CHC Executive Directors was conducted to identify their impressions and experiences. Information obtained from this exploratory study should be beneficial in educating the next generation of healthcare administrators. 相似文献
45.
Gladys I. Rodriguez John G. Kuhn Geoffrey Weiss Pearl De La Cruz Pamela New Suzanne M. Fields John R. Eckardt Liz Campbell Gary M. Clark Susan G. Hilsenbeck Daniel D. Von Hoff 《Investigational new drugs》1999,16(1):57-67
In this phase I study, terephthalamidine was administered as a 120-hour continuous infusion repeated every 21 days. Thirteen patients received 27 courses of terephthalamidine at four dose levels (14, 28, 46, and 70 mg/m2/day). Dose-limiting toxicity consisted of profound and intractable anorexia, weight loss and prostration in all patients. Toxicity was delayed and accompanied by hyponatremia and hypokalemia. No hematologic or other toxicity was documented. One patient with adenocarcinoma of the lung had a 40% decrease in mediastinal lymph nodes and resolution of a pleural effusion lasting 2 months. Pharmacokinetic analysis by HPLC was performed in all patients during their first course. The harmonic mean terminal half-life for terephthalamidine was 23 hours with a plasma clearance of 1.7 l/hr/m2. Both plasma concentrations achieved during infusion (r2 = 0.9) and area under the curve (AUC) (r2 = 0.8) were proportional to increase in dose (p < 0.002). Renal excretion accounted for 64% of the total cumulative dose, with an average renal clearance of 1.16 l/hr/m2. Due to the unacceptable toxicity seen at all doses with this schedule, no further studies are recommended unless the mechanism of toxicity is better understood and can be prevented. 相似文献
46.
A I Fields A Rosenblatt M M Pollack J Kaufman 《American journal of diseases of children (1960)》1991,145(7):729-733
We evaluated home care costs and the cost-effectiveness of home care vs alternative institutional care for respiratory technology-dependent children in a Medicaid Model Waiver Program. "Cost-savings" was measured as the difference between the established Medicaid reimbursable charges to enact an individualized care plan at a long-term care institution and the actual Medicaid reimbursements for home care. Ten patients--six dependent on mechanical ventilation and four with a tracheostomy who were receiving oxygen--were included in the analysis. The mean (+/- SD) annual home care costs were $109,836 +/- $20,781 for ventilator-dependent children and $63,650 +/- $12,350 for oxygen-dependent patients with a tracheostomy, representing annual savings of approximately $79,000 per patient and $83,000 per patient, respectively. The largest portion of home care reimbursements was for nursing care, accounting for 69.0% and 59.0% of the two patient groups. The full program (50 patients) has the potential for a savings of $4 million per year. 相似文献
47.
Szucs P Allegra JR Fields LA Grabiner FR Lavery R Prusik T Tortella B 《Air medical journal》2000,19(1):19-21
INTRODUCTION: The safety and efficacy of medications stored on air medical helicopters may be adversely affected by extreme temperatures. The purpose of this study was to determine whether temperatures inside an air medical helicopter drug box were within the U.S. Pharmacopeia recommendations for controlled room temperature. This is defined as a temperature between 15 degrees and 30 degrees C (59 degrees and 86 degrees F) with a mean kinetic temperature of less than 25 degrees C (77 degrees F). An additional goal was to determine whether time/temperature indicator labels can reliably monitor mean kinetic temperatures. METHODS: Temperatures were monitored with miniature electronic temperature recorders and color-changing time/temperature indicator labels. RESULTS: The mean kinetic temperatures for the summer and winter periods were 25.1 degrees C (77.2 degrees F) and 12.7 degrees C (54.8 degrees F), respectively. In the summer, the electronic recorders logged temperatures exceeding 25 degrees C (59 degrees F) 37% of the time and more than 30 degrees C (86 degrees F) 6% of the time. In the winter, temperatures less than 15 degrees C (59 degrees F) were recorded 83% of the time. The mean kinetic temperatures obtained from the electronic recorder and the time/temperature indicator labels differed by less than 0.7 degree C (1.3 degrees F). The results show that medications on an air medical helicopter are subject to temperatures out of the recommended range and that time/temperature indicator labels can reliably monitor mean kinetic temperatures. 相似文献
48.
49.
Cardiopulmonary bypass, initiates a generalised response, which is primarily defensive in nature. This response is self regulated and terminated spontaneously. Obvious problems are complement and leucocyte activation, but several other cascades are also stimulated, which interact, accentuate or modulate this response. These supporting cascades include, release of inflammatory cytokines, an activation of kallikrein system, clotting and fibrinolytic mechanisms, and arachidonic acid metabolism. Because of an effective autoregulatory mechanism, only a small proportion of patients (<3%), undergoing cardiopulmonary bypass are adversely effected by this process. Prognosis of these patients is often unpredictable, but in general, high risk patients are likely to suffer most. A number of specific and non specific artificial measures have been introduced to control postperfusion problems, resulting from this process. These control measures are usually effective against a specific component of this generalised problem, and often fail to achieve desired effects. Efficacy of control measures is further limited by a continued activation of complement and leucocytes, via interactions between the mentioned inflammatory cascades. In view of these limitations, we have introduced certain modifications in our previously reported control strategy. These include an early identification of high risk and susceptible individuals and using specific inhibitors of complement activation for both initial and terminal stages. 相似文献
50.