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81.
82.
C-reactive protein (CRP), a marker of inflammation, has been identified as a risk factor for cardiovascular disease and mortality. Using data on adults aged 20 and over from the fourth National Health and Nutrition Examination Survey, a nationally representative cross-sectional survey, we examined the association between socioeconomic status and CRP in US adults (N=7634). Socioeconomic variation in CRP occurred only at very high levels of CRP (>10.0 mg/L). There was no significant difference in the prevalence of moderate (1.1-3.0 mg/L) or high values of CRP (3.1-10.0mg/L) by socioeconomic status; however, among those with family income at or below the poverty level, 15.7% had very high levels of CRP (greater than 10.0 mg/L), compared to only 9.1% of those in families above the poverty level. Logistic regression results indicate that acute illness, chronic conditions, and differential health behaviors account for about two-thirds of this association. African Americans, Hispanics, and women were more likely to have high levels of CRP. Obesity was the largest risk factor for every level of CRP above normal. Results suggest that differences in very high CRP may be due to factors beyond acute illness and may also reflect chronic health, behavioral and disease processes associated with low socioeconomic status.  相似文献   
83.
Using repair‐proficient and repair‐deficient strains of E.coli, we investigated the application of a liquid incubation assay to measure the DNA‐damaging activity of ethanol‐soluble fecal extracts. This method appears to be suitable for the study of a wide range of sample types. It was used to measure the DNA‐modifying activity of ethanol‐soluble fecal extracts from a group of European colorectal cancer patients. Data were compared with those from Europeans of similar age and sex distribution who did not have bowel cancer. We also studied groups of Maoris, Samoans, and European Seventh‐Day Adventists who followed an ovo‐lacto vegetarian diet. There are significant levels of DNA‐modifying materials in the feces of many Europeans on a mixed diet, regardless of whether or not they have cancer. The number of positive samples was less in the Polynesian groups, and there were no samples that could be unequivocally scored as positive in the Seventh‐Day Adventist groups. We conclude that diet can significantly reduce the level of ethanol‐soluble mutagens, at least in New Zealand Europeans. The data may provide an explanation for the reduced incidence of bowel cancer in Seventh‐Day Adventist groups.  相似文献   
84.

Background  

Contrast-enhanced cardiac MRA suffers from cardiac motion artifacts and often requires a breath-hold.  相似文献   
85.
86.
The mucosal epithelium of the pharyngeal tonsil was studied in 10 conventionally raised sheep by scanning and transmission electron microscopy. The surface of the tonsil was covered by two types of topographically and ultrastructurally distinct epithelium. The epithelium overlying the lymphoid follicle region (follicle-associated epithelium) was compressed by adjacent ciliated epithelium and consisted of predominantly non-ciliated cells of varying height. The majority of these cells possessed microvilli or microfolds of varying number, height and density on their surface. Small numbers of squamous cells and, occasionally, intermediate cells were also present in these areas. Ultrastructurally, the microvillous cells showed features similar to M cells which occur in other mucosal sites. They contained cytoplasmic vesicles and vacuoles and formed intercellular digital junctions. Between these cells was a heavy infiltration of lymphoid cells. Focal disintegration of the mucosal epithelium was occasionally seen. The epithelium covering non-follicle areas consisted of mainly ciliated cells interspersed with some goblet cells and squamous cells, morphologically resembling those elsewhere in the respiratory tract. These findings have provided evidence which confirms that the ovine pharyngeal tonsil is part of the respiratory tract-associated lymphoid tissue.  相似文献   
87.
Eight community trials were carried out by the Onchocerciasis Control Programme in West Africa to determine the safety of the new microfilaricide ivermectin during large-scale treatment of onchocerciasis. The trial areas were located in eight different countries and varied greatly in endemicity level; a total of 50,929 persons were treated and monitored for 72 hours. Overall treatment coverage was 60% of the census population, the main reasons for non-treatment being the exclusion criteria. Of those treated, 9% reported with adverse reactions, 2.4% with moderate reactions, and 0.24% with severe reactions. Most reactions were reported during the first day of follow-up, the most frequent severe reaction being severe symptomatic postural hypotension (in 49 cases). Three cases of severe dyspnoea were life-threatening but their relationship with ivermectin treatment is uncertain. The incidence of adverse reactions was directly related to skin microfilarial load and was highest in the foci with the highest endemicity levels. Treatment resulted in 98% reductions in mean microfilarial loads at all endemicity levels. The benefit of treatment largely compensated for the discomfort due to adverse reactions, which were all transient and managed successfully. Ivermectin thus appears to be sufficiently safe for large-scale treatment but monitoring by resident nurses for at least 36 hours is recommended.  相似文献   
88.
In vitro drug sensitivity testing, both by optical colony counting and by a [3H]-TdR incorporation assay, was performed on human tumour cells proliferating in soft agar cultures. Cells from two different human tumour cell lines, 5 different human tumour xenografts, and 94 different primary human tumour specimens of various histologic types were studied. Regression analysis comparing the results of the colony counting assay and the [3H]-TdR assay revealed good to excellent correlations between the two assay endpoints for quantitating the effect of in vitro anticancer drug exposure for a large number of different agents. The presence of pre-existing tumour cell aggregates complicates the performance of the optical colony counting assay. The [3H]-TdR incorporation assay is more sensitive and reproducible than the colony counting assay when performed on samples containing a large number of initially seeded tumour cell aggregates.  相似文献   
89.
Like most other public health agencies, the Georgia Department of Human Resources, Division of Public Health (DPH) has encountered a growing number of questions and conflicts with ethical implications. To address these and other questions, DPH started to develop a framework, in January 1985, specifically related to solving problems, setting priorities, and developing policy that adds an ethical perspective. DPH must deal with issues and conflicts that transcend the traditional model of medical care: with the new economic reality, programs must continue with less resources; medical technology is now raising questions, but not necesarily answers, related to life and death; and the rights and responsibilities of individuals and institutions are not clearly defined. In this context, DPH has started to examine ethical considerations with respect to the individual and the community. An interface exists between ethical theory and health care. Over the years, however, this relationship has assumed different manifestations, ranging from the formation of precise conduct codes for health care professionals to the establishment of review boards that examine specific morally questionable procedures. DPH's purpose in applying ethical theory to its health care practices is not to develop an inflexible code nor a committee to review isolated cases of moral conflict. The purpose is to use ethical theory as a form of vision for the remainder of the 1980s and beyond.  相似文献   
90.
1. All children should receive one form of systemic fluoride and appropriate forms of topical fluoride. 2. If a child is not receiving optimally fluoridated water, the dentist or physician should prescribe dietary fluoride supplements (tablets or drops). 3. The correct dosage must be determined based on patient age and fluoride content of the patient's main water source(s). 4. Special attention is necessary concerning fluoride intake for children breast feeding or consuming infant formula. 5. To arrive at the correct fluoride dose, these steps should be followed: A. Always have a sample of the main drinking water source (usually home water) analyzed for the fluoride content before prescribing a fluoride supplement, if you do not have other specific knowledge of water fluoride content. The Medical College of Georgia (Department of Oral Biology - Dr. Whitford) provides water fluoride assay services. B. When the fluoride content of the water has been determined, the fluoride level and the child's age should be matched on Table 1 to arrive at the correct supplement dose. 6. Dr. Alderman, Director of the Office of Dental Health, Division of Public Health, Georgia Department of Human Resources, can provide lists of communities in Georgia that are optimally fluoridated.  相似文献   
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