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991.
OBJECTIVES: In England, the Department of Health places high priority on reducing the variation in unit costs of National Health Service (NHS) hospitals. Efficiency targets are set for hospitals to create incentives for relatively high cost hospitals to reduce their costs and shift performance closer to that of their lower cost counterparts. We examine empirically the dispersion in unit costs to assess the extent of variation in the productivity of hospitals and trends over time. METHODS: We use econometric panel data techniques on data from 235 NHS acute hospital trusts over a six-year period, 1994/95 to 1999/00, supplemented with information from semi-structured interviews with key individuals in hospitals and purchasing bodies. RESULTS: There appears to have been no reduction in variation during this period. Relative unit costs for individual trusts also appear stable, with little movement from relatively high cost to low cost. Judging from limited quantitative evidence outside health care, the variation in costs between NHS hospitals may be comparatively low. CONCLUSIONS: Given all the other aspects of hospital performance that government is seeking to change, reduction in the dispersion of unit costs per se should not be a major policy objective. It is far more important to examine variation in quality-adjusted unit costs. 相似文献
992.
The case of a child with Apert syndrome is presented in which the development and rupture of an intracranial mycotic aneurysm occurred secondary to multiple infectious complications following craniofacial surgery. An endovascular procedure was utilized in an attempt to embolize the aneurysm and parent vessel. The patient recovered from her infections, but retained a residual right hemiparesis and left cranial nerve III palsy at the time of discharge. To our knowledge, this is the first report of a mycotic aneurysm developing after a craniofacial procedure. Risk factors leading to aneurysm formation in this case are presented, as well as a literature review of neurological complications following craniofacial surgery. 相似文献
993.
994.
Sidebottom AC Brown JE Jacobs DR 《European journal of obstetrics, gynecology, and reproductive biology》2001,94(2):216-223
OBJECTIVE: To determine patterns of subcutaneous body fat change from preconception through 6 weeks postpartum, and factors that modify them. STUDY DESIGN: A prospective study of 557 healthy women enrolled prior to pregnancy. Main outcome measure: Body weight and skinfold thickness at the thigh, triceps, and subscapula, preconception, in each trimester, and 6 weeks postpartum, along with other variables. RESULTS: Subcutaneous body fat stores remained stable (P>0.13) during the first 6 weeks after conception, and increased from 6 to 35 weeks by 1.5 mm at the triceps, 4.2 mm at the subscapular, and 7.3 mm (P<0.01) at the thigh areas. Body fat changes correlated poorly with weight changes, reflecting differences in the time course for the changes. They differed by preconceptional body mass index (BMI), parity, and infant gender (P<0.05). Women with the highest BMIs tended to gain less subcutaneous fat early, primiparous women gained more at thigh (P=0.01) and subscapular (P=0.027), and women carrying males had higher gains at the thigh (P=0.032) and subscapular sites (P=0.058) than other women. Breastfeeding status did not affect postpartum body fat changes, but women who breastfed exclusively had significantly lower skinfold thicknesses than non-exclusive breastfeeders from preconception through 6 weeks postpartum (P=0.041). CONCLUSION: Subcutaneous body fat is stored and utilized at different sites at specific times during and after pregnancy. The pattern and amount of change varies depending on characteristics of women and their pregnancies. 相似文献
995.
Short rib-polydactyly syndrome type III: comparison of ultrasound, radiology, and pathology findings
Golombeck K Jacobs VR von Kaisenberg C Oppermann HC Reinecke-Lüthge A Weisner D Jonat W 《Fetal diagnosis and therapy》2001,16(3):133-138
Short rib-polydactyly syndrome (SRPS; types I-IV) is an autosomal recessive, lethal skeletal dysplasia characterized by short-limb dysplasia, narrow thorax, and polydactyly. This syndrome is invariable and can be detected by 2-trimester ultrasound. The underlying gene has not been discovered yet. We report a case of SRPS subtype III Verma-Naumoff-Le Marec that was sonographically detected at 20 weeks' gestation and compare prenatal ultrasound with postmortem findings from pathology and radiology. Since the risk of recurrence is 25%, early ultrasound for consecutive pregnancies was advised and performed at 11+6 weeks' gestation in the following pregnancy without any findings. Ultrasound diagnosis in this rare case of SRPS is a valuable tool for identification and early management, since there are no specific biochemical or histopathological markers for this syndrome. Radiological and pathological findings confirmed SRPS type III and assisted in the differential diagnosis of the subtype. 相似文献
996.
C-terminal invariable domain of VlsE may not serve as target for protective immune response against Borrelia burgdorferi 下载免费PDF全文
VlsE, the variable surface antigen of the Lyme disease spirochete, Borrelia burgdorferi, contains two invariable domains, at the amino and carboxyl termini, respectively, which collectively account for approximately one-half of the entire molecule's length and remain unchanged during antigenic variation. It is not known if these two invariable domains are exposed at the surface of either the antigen or the spirochete. If they are exposed at the spirochete's surface, they may elicit a protective immune response against B. burgdorferi and serve as vaccine candidates. In this study, a 51-mer synthetic peptide that reproduced the entire sequence of the C-terminal invariable domain of VlsE was conjugated to the carrier keyhole limpet hemocyanin and used to immunize mice. Generated mouse antibody was able to immunoprecipitate native VlsE extracted from cultured B. burgdorferi B31 spirochetes, indicating that the C-terminal invariable domain was exposed at the antigen's surface. However, this domain was inaccessible to antibody binding at the surface of cultured intact spirochetes, as demonstrated by both an immunofluorescence experiment and an in vitro killing assay. Mouse antibody to the C-terminal invariable domain was not able to confer protection against B. burgdorferi infection, indicating that this domain was unlikely exposed at the spirochete's surface in vivo. We concluded that the C-terminal invariable domain was exposed at the antigen's surface but not at the surface of either cultured or in vivo spirochetes and thus cannot elicit protection against B. burgdorferi infection. 相似文献
997.
Incomplete sterilization of Mycobacterium tuberculosis Erdman cultures followed 1 h of incubation in low concentrations of glutaraldehyde (0.5 and 1.0%) or azide. In contrast, 2.5% glutaraldehyde, paraformaldehyde (2 or 4%), Vesphine IIse or 5% formalin sterilized these samples after 1 h. These results suggest caution in removing fixed M. tuberculosis samples from biosafety level 3. 相似文献
998.
Jacobs R Manders E Van Looy C Lembrechts D Naert I van Steenberghe D 《Clinical oral implants research》2001,12(2):167-173
In the present study, speech function was assessed in edentulous patients wearing fixed or removable dental prostheses supported or not by oral implants. A total of 138 patients participated in the present research. The experimental group (n=113) was divided in 4 subgroups. Subgroup FD/FFPi comprised 22 patients with a maxillary full denture (=FD) and a mandibular fixed full prosthesis on implants (=FFPi). Subgroup FFPi/ND consisted of 27 patients with a maxillary fixed full prosthesis on implants and a natural dentition (=ND) in the mandible. Subgroup FD/ODi included 49 patients wearing a maxillary full denture and a mandibular overdenture on 2 implants (=ODi). Subgroup FFPi/FFPi comprised 15 patients having a fixed full prosthesis on implants in both jaws. The outcome of the logopedic screening of the experimental group was compared with that of a control group of subjects having a natural dentition (ND/ND; n=25). A standard clinical procedure for evaluation of speech was carried out by a speech pathologist. Besides, specific oral and prosthetic parameters were scored in all patients. It was established that one or more pronunciation difficulties occurred in 84% of the patients of the experimental group. This was significantly more than in the control group, where half the number of subjects had some speech deficiencies. No clear influence of specific oral and prosthetic parameters could be identified. From the present results, it could be concluded that in patients rehabilitated with oral implant-supported prostheses speech disorder is more frequently observed than in subjects with a natural dentition. 相似文献
999.
Share L Chaikin S Pomeranets S Kiwi R Jacobs M Fanaroff AA 《Seminars in perinatology》2001,25(2):107-113
Early onset Group B Streptococcus (EOGBS) disease, defined by an onset within the first 72 hours of life, occurs in 1.3 to 3.7 per 1,000 live births. The authors sought to determine the impact of the new CDC/AAP/ACOG guidelines on the prepartum screening practice, intrapartum management, incidence of EOGBS infection, and evaluation of neonates born to GBS colonized women at University Macdonald Women's Hospital (Cleveland, OH). A retrospective analysis by chart review was conducted from January 1, 1995 to December 31, 1997 of women identified as GBS colonized during prenatal screening. These women were then divided into 2 groups: period I, women who delivered January 1, 1995 to June 30, 1996 (before institutional implementation of the guidelines for management of GBS colonization]; and period II, women who delivered July 1, 1996 to December 31, 1997 after implementation of the guidelines. A chart review was conducted for infants 72 hours old, and GBS culture positive (blood or CSF) for the same time period. In complying with the new screening and treatment guidelines, there was a significant increase in the number of mothers screened and the detection of maternal colonization, plus a 63% reduction in EOGBS. There was also a substantial reduction in the number of invasive procedures on the neonates. The authors conclude that the new guidelines are both medically and economically effective. 相似文献
1000.
Lee JH Tang MX Schupf N Stern Y Jacobs DM Tycko B Mayeux R 《American journal of medical genetics》2001,103(2):121-127
To investigate whether mortality risk is influenced by apolipoprotein E (APOE) genotype and whether the risk differs by ethnicity, we compared the mortality risk in 2,112 individuals > or = 65 years of age residing in northern Manhattan in New York. Mortality risks associated with the APOE genotype, adjusted for sex, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides, differed significantly by ethnic group. Among Caucasian and Hispanics, the E2/E3 genotype was associated with the lowest mortality risk in the multivariate Cox proportional hazards modeling, adjusted for lipid levels, whereas mortality risk did not differ substantially between the E4/E3 and E3/E3 genotypes. Among African-Americans, the E2/E3 genotype was not associated with the lowest mortality risk, but the E4/E3 genotype was. Adjustment for heart disease, diabetes, and stroke reduced mortality risk associated with each genotype by about 50% for all ethnic groups, but the patterns remained the same. Although we cannot rule out the possibility of a healthy survival bias, our analyses designed to examine healthy survival by comparing risk of mortality in groups who were younger or older at entry do not support this possibility. Our findings suggest that the APOE genotype is associated with mortality and that the genotypic risks differ by ethnic group. Nearly 50% of the mortality risk associated with the APOE genotype appears to act through major chronic diseases, but those diseases only partially explain the mechanism by which the genotypic risk acts. To better understand the observed ethnic differences in mortality risk by genotype, a detailed prospective study is needed to examine the relationships among APOE, other candidate genes, health conditions, and eventual death. 相似文献