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Before informed advice can be given to parents and health care workers about the need for pertussis immunisation, an estimate of the risk of inadequately immunised children contracting pertussis is needed. The study reported here was conducted because the literature contains no such estimates of risk. Analysis was made of a county's Notification of Disease Reports. Computation was carried out of age-specific annual notification rates of pertussis amongst adequately and inadequately immunised children. It was found that inadequately immunised one-year-old children probably have more than a one in six chance of developing pertussis before age ten.  相似文献   
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Dental treatment is a dyadic encounter. Yet research on the dentist-patient dyad has tended to focus on patient perceptions of dentist, to the neglect of dentist perceptions of patient. Previous theoretic and qualitative work on caregiver perceptions of patients suggested three dimensions of evaluation. Dentists (N=618) rated their patients on items taken from two prior studies. Dentists' responses were subjected to confirmatory factor analysis. The analysis substantiated the existence of three evaluative dimensions: compliance, tractability, and likability. Further analysis showed that the three dimensions formed a Guttman simplex, revealing a second-order factor of selectivity and allowing a classification of dentists on the basis of patient selectivity.This study was funded by a grant from the University of Connecticut Research Foundation.  相似文献   
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In 20 white leghorn chickens, the effect of proximity (proximal vs. distal) to the repair site and the effect of sheath excision versus sheath repair on biochemical matrix formation in the healing zone 2 flexor tendon were studied. In 14 animals, the profundus tendon of the long toe on both feet was lacerated and repaired in zone 2. In the right foot, the sheath was repaired, and on the left foot, the sheath was excised. Segments proximal and distal to the laceration site were studied at six weeks postrepair compared to control segments. Sheath excision versus sheath repair had no effect on the net matrix formation of the healing flexor tendon. A higher DNA content and lower hydroxyproline and hexosamine contents were present in the healing tendons, indicating the healing process was not complete at six weeks. Sheath excision versus sheath repair had no effect on net matrix formation in the healing tendon. There is no difference in DNA content or glycosaminoglycan content in the proximal versus distal segments. There was a significantly greater net hydroxyproline content in the proximal segment versus the distal segment of the healing tendon, which was not present in similar control segments. These results support the concept that the zone 2 flexor tendon does not respond to injury as a homogeneous structure.  相似文献   
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BACKGROUND: In 2002 the Department of Health published a list of 20 indicators to judge the performance of the 302 primary care organisations (PCOs) in England during 2001-2002. General practitioners (GPs) have expressed doubts about the relevance, applicability and evidence base of these indicators for actual practice. AIMS: To fashion NHS performance indicators to be acceptable and relevant to practicing GPs. DESIGN OF STUDY: A Delphi technique followed by simple mathematical modelling. METHODS: We asked a group of 24 senior GP educators to place the Department of Health performance indicators in rank order as markers of quality in general practice. We found just seven indicators comprised 73% of the markers chosen and all seven were chosen by over three-quarters of the responders. Using a simple 'sign test' system, we then calculated a composite points score for all 302 PCOs. RESULTS: We found that there were almost twice as many PCOs at the upper and lower ends of performance and fewer in the middle than we predicted theoretically. The results suggest that pan-PCO or practice factors account for the low performance scores of 16 of 35 PCOs with extremely poor performance and for the high scores of 17 of the 36 PCOs with extremely high performance. CONCLUSION: We have developed a method that shows how numerous Department of Health performance indicators can be merged into a single composite performance score. We show that this composite performance score is easy to derive, simple to interpret, is acceptable to GPs, and has face validity.  相似文献   
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The efficacy of cefazolin or cefpirome alone or combined with rifampin was compared with that of vancomycin alone or combined with rifampin in an experimental model of methicillin-resistant, beta-lactamase-producing, coagulase-negative staphylococcal endocarditis. Phenotypically, the mecA gene-positive strain used in vivo did not exhibit methicillin resistance by the agar dilution or disk susceptibility method but was resistant in vitro (oxacillin MIC, 64 micrograms/ml) by the microtiter dilution method with 2% NaCl supplementation. Macrodilution broth susceptibilities of standard inocula failed to demonstrate cross-resistance of staphylococci to cefazolin (MIC, 8 micrograms/ml) or cefpirome (MIC, 4 micrograms/ml). In vivo, vancomycin and cefpirome had similar activities, and both regimens were more effective than was cefazolin alone. While the MIC of rifampin was low (0.031 micrograms/ml), monotherapy with rifampin resulted in a bimodal distribution of outcomes due to the expected emergence of resistant mutants. The results in vitro of time-kill synergy studies using rifampin in combination with cefazolin or cefpirome varied with the antimicrobial concentrations tested and did not reliably predict activities in vivo of rifampin-beta-lactam combination therapies. Cefpirome, but not cefazolin or vancomycin, in combination with rifampin was synergistic in vivo. Cefpirome in combination with rifampin was more effective than was cefazolin in combination with rifampin. Both cephalosporin-rifampin regimens were significantly more effective than was cephalosporin or vancomycin monotherapy and were as effective as vancomycin combined with rifampin. These data support further evaluation of rifampin-beta-lactam combinations as possible alternative therapies to vancomycin-containing regimens for selected methicillin-resistant coagulase-negative staphylococcal infections.  相似文献   
8.
A comparison study of dynamic visual acuity (DVA) was conducted using samples of nonathletic college students and college baseball players. The experimental population consisted of 17 male baseball players ranging in age from 19-24 years. The control population was made up of 25 male graduate students ranging in age from 23-29 years. Subjects reported the direction of a 20/25 "Landolt C" target exhibiting uniform angular motion produced by a projection system. Angular target velocities between 10 deg/sec and 110 deg/sec with an exposure time of 400 ms were used. The results showed a statistically significant difference between the two groups' DVA. The mean DVA for the baseball players was 82.35 deg/sec and 69.90 deg/sec for the control group.  相似文献   
9.
Measurements of aerobic fitness, weight, blood pressure, and lipids were made in 1000 sedentary men and women entering a fitness programme, and were repeated 2 years later in 733 subjects. Cross-sectional analyses including (a) comparisons of CHD risk factors in subjects grouped as "low", "low/moderate", "moderate/high", and "high" fitness, and (b) multiple regression analyses of relationships between fitness and risk factors showed that fitter subjects had better risk profiles than less fit. Longitudinal analyses including (a) comparisons of risk factor changes in subjects grouped as fitness "losers", "stable", "small gain", and "large gain", and (b) multiple regression analyses of relationships between fitness change and risk factor changes showed that fitness change was largely unrelated to risk factor changes. The study supported the existence of beneficial associations between fitness and risk factors but not cause and effect relationships.  相似文献   
10.
In this communication, we examine the specificity of anti-herpes simplex virus (HSV) cytotoxic T lymphocytes (CTL). Serological studies of the two related HSV serotypes (HSV-1 and HSV-2) have revealed both type-specific and cross-reactive antigenic determinants in the viral envelope and on the surface of infected cells. By analysis of cytotoxicity of CTL, generated in vitro by restimulation of splenocytes from mice primed with one or the other HSV serotype, the recognition of both type-specific and cross-reactive determinants on infected target cells by anti-HSV CTL was detectable. Thus, effector cells generated by priming and restimulating with the same virus recognized both type-specific and cross-reactive determinants on target cells infected with the homologous virus, but only cross-reactive determinants on target cells infected with the heterologous HSV serotype. CTL generated by restimulation with the heterologous virus were capable of recognizing only the cross-reactive determinants on either HSV-1- or HSV-2-infected target cells. These results indicate that two subpopulations of CTL exist in a population of anti-HSV immune spleen cells--those which recognize type-specific determinants and those specific for cross-reactive antigenic determinants present on the surface of HSV infected cells. The type-specific subset of anti-HSV CTL was shown to recognize the gC glycoprotein of HSV-1 infected target cells. In addition to the gC glycoprotein, at least one other type-specific surface antigen was also recognized by anti-HSV CTL in addition to the cross-reactive determinants recognized by anti-HSV CTL.  相似文献   
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