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31.
It remains unclear which MHC loci are involved in susceptibility to autoimmune diseases and immune deficiencies. We have chosen to evaluate whether different alleles of tumour necrosis factor-alpha (TNF-alpha) are important, as TNF has been implicated in the etiology of many immunological disorders. We have shown previously that a restriction fragment length polymorphism in the TNF region correlates with MHC ancestral haplotypes. We therefore examined the effect of ancestral haplotype on the activity of TNF-alpha in culture supernatants of lymphoblastoid cell lines. The results demonstrate that TNF-alpha activity in supernatants of 8.1 (A1, B8, DR3) cell lines was higher than that present in the supernatants from cells homozygous for eight different MHC ancestral haplotypes, and indicate that polymorphisms in TNF-alpha, or in other MHC genes that regulate TNF, may be responsible for the 8.1 phenotype.  相似文献   
32.
This study evaluates the impact of health insurance as a substitute for social class on tumor location, presentation, stage, grade, and age-adjusted survival in an African-American population. Patients were stratified by insurance into two groups: group 1 (private insurance and Medicare parts A & B) and group 2 (Medicaid, Medical Charity, self-pay, uninsured, or unemployed). A total of 212 patients were evaluated. Of these, 210 patients were insured or had Medical Charity, and two were uninsured. The type of health insurance did not significantly affect age-adjusted survival. However, age and stage at presentation were positive predictors of age-adjusted survival. Higher socioeconomic status was associated with group 1 health insurance.  相似文献   
33.
A completely new method of initiating the homogeneous radical polymerization of methyl methacrylate in bulk or in solution via the photogeneration of an electron hole pair in colloidal cadmium sulfide is presented. A polymerization mechanism involving an excited cadmium sulfide particle in both the initiation and termination steps is proposed. In the initiation a methyl methacrylate molecule is oxidized by a positive hole photogenerated in a CdS particle, which results in a novel chain-end structure of the poly(methyl methacrylate) (PMMA). Degradative chain transfer to reduced excited cadmium sulfide particles is responsible for chain termination. Thus, for the first time, a detailed polymerization mechanism in which all states of the polymerization, i.e., initiation, propagation, chain transfer and termination, is presented for the polymerization of vinyl monomers initiated by semiconductors. Thermogravimetry (TG) showed that the newly synthesized PMMA has greatly enhanced thermal stability when compared to normal radically prepared PMMA. In fact, the thermal stability approaches that of anionically prepared PMMA but is experimentally much easier to prepare. This technique enables the homogeneous embedding of CdS particles in a polymer matrix.  相似文献   
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35.
A novel intrahepatic biliary cell culture/in vivo transplantation system has been developed with an essentially pure population of bile ductular epithelial cells isolated from rat liver 6–12 weeks after bile duct ligation. In primary culture, these cells retain staining strongly for -glutamyltranspeptidase and glutathione S-transferase P. The cytoplasm of cultured bile ductular cells reacts with an anti-laminin antibody, but loses immunoreactivity with a monoclonal anti-cytokeratin 19 antibody. Semiconservative DNA synthesis in the cultured cells was dependent upon the continued presence of 10% fetal calf serum in the medium. Replicating bile ductular cells could be subcultured for a finite number of passages. In addition, freshly isolated bile ductular epithelial cells gave rise to well differentiated bile ductular structures when transplanted into the interscapular fat pads of syngeneic recipient rats.Presented at the Proceedings of the International Meeting on Normal and Neoplastic Growth in Hepatology, Bari, Italy, June 1989.This work was supported by USPHS Grant RO1 CA39225 to Dr. Sirica by the National Cancer Institute, Department of Health and Human Services.  相似文献   
36.
A free exploration test was used to examine the effects of LSD on investigatory responding and locomotor activity in a novel environment. Rats were injected with 20–30 g/kg LSD or saline prior to being placed in a home cage. After 10 min, a door was opened permitting entry into a larger holeboard chamber where crossovers, rearings, hole pokes, and routes of locomotion were monitored. When administered either 10 or 30 min prior to testing, LSD reduced the time spent in the holeboard chamber only during the first half of a 1-h session, resulting in a corresponding reduction in all holeboard activity measures. In the subsequent 30 min, LSD-treated rats maintained a steady level of responding, in contrast to the continual derement exhibited by controls. Despite their initial avoidance of the holeboard, LSD-treated rats made consistently longer hole pokes into floor holes and showed a more diversified pattern of locomotion than did controls throughout the 1-h session. Most striking was the failure of LSD-treated rats to establish the stereotyped excursion routes, characteristic of controls, from the home cage to various parts of the holeboard. It is suggested that LSD potentiates both neophobic (avoidance) and investigatory responses to a novel environment by retarding the rate of behavioral habituation.  相似文献   
37.
Case-control methodology was used to evaluate the significance of vascularity in small breast carcinomas with regard to the presence or absence of axillary lymph node metastases. Vascularity was assessed in 32 axillary node positive primary breast tumours (LN+ve) less than 2 cm in size and compared with 56 control axillary node negative primary tumours (LN–ve), which were matched for histological type and grade and tumour size. This study design employed computer-assisted video analysis (CAVA) to assess the total blood vessel perimeter (BVP), total blood vessel area (BVA), and total blood vessel density (BVD) throughout a tissue section that encompassed an entire cross section of the tumour and its immediate periphery. The BVA and BVD in these tumours were not significantly different between LN+ve and LN–ve groups. The LN–ve carcinomas had, on average, a significantly (P < 0.05) higher total BVP (3355 µm/mm2) than LN+ve tumours (2771 µm/mm2). 'Hot spot' areas were also independently assessed by two pathologists and the same areas measured by CAVA. A strong correlation (P < 0.001) between the two methods of assessment of BVD of the neovascular 'hot spots' was found; however, no association with axillary lymph node metastasis was found using either method of assessment. In conclusion, vascularity assessed by either blood vessel density or blood vessel size in primary invasive breast cancers less than 2 cm in diameter showed no association with axillary lymph node metastasis; in fact a negative association was found with total BVP of whole tumour sections and BVD in 'hot spots' using CAVA. Further, this study has established a computer-assisted method of quantifying vascularity in solid neoplasms and is a positive step towards a standardised approach to this diverse and methodologically variable area.  相似文献   
38.
The identification of intimate partner violence (IPV) against women as a public health problem has led to routine health care site– based screening and brief intervention policies. However, there is a lack of evidence supporting the usefulness and safety of such policies. Our objective was to ascertain the acceptability, usefulness, and harm of a brief health care site– based screening intervention. In this qualitative study, semistructured interviews were conducted with 36 women several weeks after a standardized screening intervention in either an emergency department (adult and paediatric) or primary health care setting. The majority of women (97%) welcomed the IPV screening intervention and perceived it as nonthreatening and safe. The women reported no increased risk of harm because of the screening. The responses showed that the intervention had a therapeutic and educational quality, and the attitude and approach of the person asking the intervention questions was critical to a positive outcome. Women without a history of violence cautioned that IPV screening may be offensive to those who are abused, whereas those who reported abuse thought IPV screening was essential “to stop it [from] happening.” Our findings challenge concerns that IPV screening is offensive to women and increases their potential for danger. Participants were appreciative of the opportunity to tell their abuse stories in a safe and supportive context, and challenged the health care system to implement IPV screening, asking “What took you so long?”  相似文献   
39.
This articles serves as a guide to using cost-effectiveness analysis (CEA) to address health equity concerns. We first introduce the "equity impact plane," a tool for considering trade-offs between improving total health—the objective underpinning conventional CEA—and equity objectives, such as reducing social inequality in health or prioritizing the severely ill. Improving total health may clash with reducing social inequality in health, for example, when effective delivery of services to disadvantaged communities requires additional costs. Who gains and who loses from a cost-increasing health program depends on differences among people in terms of health risks, uptake, quality, adherence, capacity to benefit, and—crucially—who bears the opportunity costs of diverting scarce resources from other uses. We describe two main ways of using CEA to address health equity concerns: 1) equity impact analysis, which quantifies the distribution of costs and effects by equity-relevant variables, such as socioeconomic status, location, ethnicity, sex, and severity of illness; and 2) equity trade-off analysis, which quantifies trade-offs between improving total health and other equity objectives. One way to analyze equity trade-offs is to count the cost of fairer but less cost-effective options in terms of health forgone. Another method is to explore how much concern for equity is required to choose fairer but less cost-effective options using equity weights or parameters. We hope this article will help the health technology assessment community navigate the practical options now available for conducting equity-informative CEA that gives policymakers a better understanding of equity impacts and trade-offs.  相似文献   
40.
OBJECTIVEGenetic risk scores (GRS) aid classification of diabetes type in White European adult populations. We aimed to assess the utility of GRS in the classification of diabetes type among racially/ethnically diverse youth in the U.S.RESEARCH DESIGN AND METHODSWe generated type 1 diabetes (T1D)- and type 2 diabetes (T2D)-specific GRS in 2,045 individuals from the SEARCH for Diabetes in Youth study. We assessed the distribution of genetic risk stratified by diabetes autoantibody positive or negative (DAA+/−) and insulin sensitivity (IS) or insulin resistance (IR) and self-reported race/ethnicity (White, Black, Hispanic, and other).RESULTST1D and T2D GRS were strong independent predictors of etiologic type. The T1D GRS was highest in the DAA+/IS group and lowest in the DAA/IR group, with the inverse relationship observed with the T2D GRS. Discrimination was similar across all racial/ethnic groups but showed differences in score distribution. Clustering by combined genetic risk showed DAA+/IR and DAA/IS individuals had a greater probability of T1D than T2D. In DAA individuals, genetic probability of T1D identified individuals most likely to progress to absolute insulin deficiency.CONCLUSIONSDiabetes type–specific GRS are consistent predictors of diabetes type across racial/ethnic groups in a U.S. youth cohort, but future work needs to account for differences in GRS distribution by ancestry. T1D and T2D GRS may have particular utility for classification of DAA children.  相似文献   
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