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121.
Guendelman S Buekens P Blondel B Kaminski M Notzon FC Masuy-Stroobant G 《Maternal and child health journal》1999,3(4):177-187
Objectives: To compare maternal characteristics and birth outcomes of Mexico-born and native-born mothers in the United States and those of North African mothers living in France and Belgium to French and Belgian nationals. Methods: We examined information from single live birth certificates for 285,371 Mexico-born and 3,131,632 U.S.-born mothers (including 2,537,264 U.S.-born White mothers) in the United States, 4,623 North African and 103,345 Belgian mothers in Belgium, and a French national random sample consisting of 632 North African and 11,185 French mothers. The outcomes were mean birthweight, low birthweight, and preterm births. Differences between native/nationals and foreign-born mothers in each country were assessed in bivariate and multivariate analyses controlling for maternal risk factors. Results: The adjusted odds for low birthweight were lower for immigrants than native/nationals by 32% in the United States, by 32% in Belgium, and by 30% in France. The adjusted odds for preterm births were lower for immigrants compared with native/nationals by 11% in the United States and by 23% in Belgium. In France, the odds for preterm births were comparable for immigrants and naturalized mothers. Infants of immigrant mothers also had higher mean birthweights in all three countries. Conclusion: Despite their disadvantaged status, Mexico-born and North African-born women residing in the United States, France, and Belgium show good birth outcomes. These cannot be explained solely by traditional risk factors. Protective factors and selective migration may offer further clues. 相似文献
122.
123.
The effect of ultra-high molecular weight polyethylene wear debris on MG63 osteosarcoma cells in vitro 总被引:7,自引:0,他引:7
Dean DD Schwartz Z Liu Y Blanchard CR Agrawal CM Mabrey JD Sylvia VL Lohmann CH Boyan BD 《The Journal of bone and joint surgery. American volume》1999,81(4):452-461
BACKGROUND: Focal osteolysis due to ultra-high molecular weight polyethylene wear debris involves effects on both bone resorption and bone formation. METHODS: The response of MG63 osteoblast-like osteosarcoma cells to ultra-high molecular weight polyethylene wear debris isolated by enzymatic digestion of granulomatous tissue obtained from the sites of failed total hip arthroplasties was examined. Scanning electron microscopy, particle-size analysis, and Fourier transform infrared spectroscopy were used to characterize the number, morphology, size distribution, and chemical composition of the particles. Cell response was assessed by adding particles at varying dilutions to confluent cultures and measuring changes in cell proliferation (number of cells and [3H]-thymidine incorporation), osteoblast function (alkaline-phosphatase-specific activity and osteocalcin production), matrix production (collagen production and proteoglycan sulfation), and local cytokine production (prostaglandin-E2 production). RESULTS: The mean size of the particles was 0.60 micrometer, and 95 percent of the particles had a size of less than 1.5 micrometers. The number of particles per gram of tissue ranged from 1.39 to 3.38x10(9). Three of the four batches of particles were endotoxin-free. Exposure of the cells to particles of wear debris significantly increased the number of cells (p<0.05) and the [3H]-thymidine incorporation (p<0.05) in a dose-dependent manner. In contrast, the addition of particles decreased alkaline-phosphatase-specific activity and osteocalcin production. Collagen production and proteoglycan sulfation were also decreased, while prostaglandin-E2 synthesis was increased by the addition of particles. CONCLUSIONS: Ultra-high molecular weight polyethylene particles isolated from human tissue stimulated osteoblast proliferation and prostaglandin-E2 production and inhibited cell differentiation and matrix production. These results indicate that particles of wear debris inhibit cell functions associated with bone formation and that osteoblasts may produce factors in response to wear debris that influence neighboring cells, such as osteoclasts and macrophages. CLINICAL RELEVANCE: Particles of wear debris, especially ultra-high molecular weight polyethylene, have been implicated in the loosening of implants and the development of osteolysis. The present study shows that particles of ultra-high molecular weight polyethylene isolated from human tissue inhibit osteoblast functions associated with bone formation. In addition, particles of wear debris induced osteoblasts to secrete factors capable of influencing neighboring cells, such as osteoclasts and macrophages. These results suggest that osteoblasts may play a role in the cascade of events leading to granuloma formation, osteolysis, and failure of orthopaedic implants. 相似文献
124.
Evidence-based practice is an important step in the professional evolution of occupational therapy and also provides the means for state-of-the-art innovative clinical service for clients. An essential step in incorporating innovations and developments into clinical practice is through research utilization. Nine models of research utilization developed in the literature are reviewed and critiqued. These are: (1) the Conduct and Utilization of Research in Nursing (CURN) Project; (2) the Stetler-Marram Model; (3) the University of North Carolina Approach; (4) the Innovation Diffusion Process Model; (5) Killeen's Matrix of Research Activity; (6) the Iowa Model of Research In Practice; (7) the Western Interstate Commission for Higher Education In Nursing Project; (8) the Nursing Child Assessment Satellite Training Project; and (9) the Linkage Model. Research utilization models provide a framework for collaboration and the necessary conditions for research utilization activities to be successful. Copyright © 1999 Whurr Publishers Ltd. 相似文献
125.
J. Knapp P. Bokník M.C. Deng S. Huke I. Lüss O. Klein-Wiele B. Linck H. Lüss F.U. Müller P. Nacke H.H. Scheld W. Schmitz U. Vahlensieck J. Neumann 《Naunyn-Schmiedeberg's archives of pharmacology》1999,360(4):464-472
It is unknown whether protein phosphatases types 1 and 2A are present in and can regulate the tone of human vascular tissue. The expression and possible function of serine/threonine protein phosphatases (PP) type 1 (PP1) and type 2A (PP2A) were studied in isolated human coronary arteries. Catalytic subunits of PPI and PP2A were identified by means of phosphatase activity measurement in tissue homogenates, by separation of enriched extracts through affinity column chromatography, by immunoblotting with specific antibodies, by hybridization of mRNA with specific DNA probes and PCR of reverse transcribed mRNA. Based on these methods, the catalytic subunits of PP1(alpha,beta,gamma) and PP2A(alpha,beta) were identified. Appropriately, cantharidin, an inhibitor of PP1 and PP2A, increased basal tone of human isolated coronary artery rings with an EC50 of about 16 micromol/l by increasing the phosphorylation state of the regulatory light chains of myosin. In summary, PP1 and PP2A are expressed in human coronary arteries and they can alter vascular tone. 相似文献
126.
Kayser K Kaltner H Dong X Knapp M Schmettow H Vlasova E Bovin N Gabius H 《International journal of oncology》1996,9(5):893-900
Tissue sections taken from 157 potentially curatively operated lung carcinoma patients (70 epidermoid carcinomas, 68 adenocarcinomas, 15 large cell anaplastic, and 4 small cell anaplastic carcinomas) were examined by a standardized histochemical protocol in a prospective study evaluating the extent of various types of probes to serve as prognostic indicators in lung cancer. Detailed clinical records and survival data (minimum 56 weeks, maximum 96 weeks) were correlated to the results of the histochemical reactions. The study centres on monitoring the expression of galactoside-containing epitopes in tumor cells by human, animal and plant lectins: and with a monoclonal antibody. In addition, affinity-purified subfractions of natural antibodies from human serum with preferential affinity to alpha- and beta-galactosides, respectively, were employed. Significant contributions to the estimation of the survival of patients are given by clinical parameters (pT, pN stage), number of resected and positive lymph nodes and presence of tumor metastases into specific lymph nodes (No. 5 and No. 6 right and left). With respect to the relevance of subsets of beta-galactosides, the galectin from chicken liver (CL-16) and the Le(y)-specific monoclonal antibody unveiled a negative correlation at a statistically significant level. The predictive value of binding of the animal lectin CL-16 was especially pronounced for patients with advanced tumor stages, pointing to a potential role of such lectin-reactive beta-galactosides in late tumor stages or progression. 相似文献
127.
The concern for quality of health care motivates evaluation programs designed to monitor the health care system, patient outcome, and provider expertise. An array of audit methods and instruments for evaluating professional and institutional performance has been developed. Although evaluation is viewed by many as the basis for accountability and improvement of health care, few are aware that most existing evaluation programs are really data-collecting systems. Very little if any, analysis of the data is done with the objective of optimizing the system. The "sampling with intervention" procedures often used to monitor the health care delivery system are primarily directed toward the individual patient while the system and provider continue to operate in the established mode. This article outlines analytic procedures for interpreting evaluation data generated by quality control and audit systems. Five common univariate statistical quality control charts are described. 相似文献
128.
Judith A. Lesniak Sylvia M. Ruby 《Archives of environmental contamination and toxicology》1982,11(3):343-352
Sexually maturing female rainbow trout were exposed in the laboratory to 0.01 mg/L and 0.02 mg/L hydrogen cyanide (HCN) for 20 days at 10 ±0.5C. Histological sections of ovaries from these fish indicated abnormal cytoplasmic features among oocytes during their early development. Oocytes exposed to cyanide during late development exhibited altered patterns of secondary yolk deposition. Quantitative observations similarly confirm delays in secondary yolk deposition. Exposure of females to 0.02 mg/L HCN during early summer ovarian growth resulted in delayed secondary yolk deposition among 93% of the oocytes when compared with controls. When fish were exposed during mid-summer, the effects were evident at both concentrations with approximately 60% of the oocytes failing to reach the secondary yolk deposition stage at the completion of the experiment. This was further substantiated by potential growth studies which indicated a complete absence of oocytes in the final stages of secondary yolk deposition at both cyanide concentrations as compared with controls which contained 27%. The high frequency of atresia at both concentrations suggested that oocytes unable to produce secondary yolk were resorbed by the ovary through a unique form of atresia. It is also suggested that levels of cyanide as low as 0.01 mg/L have a critical effect upon the process of secondary yolk deposition within the ovary and thus significantly reduce the number of viable eggs. 相似文献
129.
A study of concerns of 100 middle-class mothers and fathers who had lost infants revealed that the death of an infant or fetus (through miscarriage) was viewed as devastating because of inadequate community recognition of the loss. The impact of these deaths and the lack of community support forces the parents to turn to their physicians from whom they attempt to seek counsel and comfort. Many physicians, unfortunately, are unable to meet the parent's needs because they cannot deal with death on the personal level, and/or their training militates against their accepting a shift in responsibility from "healer" to "counselor-consoler." Thus, an impasse often is reached in which the expectations of parents exceed the service that the physician is able or willing to render. This detracts from the physician's ability to fulfill adequately his role of provider of total care. 相似文献
130.