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1.
Elimination of indigenous measles from the United States has been a public priority since 1978. To assess the progress made toward this goal, we review the epidemiology of measles from 1963 to the present. From the 1970s through early into the recent measles epidemic, the majority of measles cases were in highly vaccinated, school-age children. This was due primarily to a 1 to 5% primary measles-mumps-rubella vaccine failure rate and nonrandom mixing patterns among school-age populations. To eliminate susceptible individuals in the school-age populations, a second dose of measles vaccine is now recommended between 5 and 6 years or 11 and 12 years by both the Advisory Committee on Immunization Practices and the American Academy of Pediatrics. Later in the epidemic, measles cases surged among unimmunized preschool children, especially among the poor in inner-city areas. Immunization rates have been documented to be low among preschool populations because of missed opportunities to administer vaccines at all health visits and barriers to access to immunizations. To raise immunization rates, the age for the first measles-mumps-rubella immunization was lowered to 12 to 15 months of age, federal immunization funding has increased, and new standards for immunization delivery have been developed and promulgated.  相似文献   

2.
Debates about the ethics of euthanasia and physician-assisted suicide date from ancient Greece and Rome. After the development of ether, physicians began advocating the use of anesthetics to relieve the pains of death. In 1870, Samuel Williams first proposed using anesthetics and morphine to intentionally end a patient's life. Over the next 35 years, debates about the ethics of euthanasia raged in the United States and Britain, culminating in 1906 in an Ohio bill to legalize euthanasia, a bill that was ultimately defeated. The arguments propounded for and against euthanasia in the 19th century are identical to contemporary arguments. Such similarities suggest four conclusions: Public interest in euthanasia 1) is not linked with advances in biomedical technology; 2) it flourishes in times of economic recession, in which individualism and social Darwinism are invoked to justify public policy; 3) it arises when physician authority over medical decision making is challenged; and 4) it occurs when terminating life-sustaining medical interventions become standard medical practice and interest develops in extending such practices to include euthanasia.  相似文献   

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The interplay between the acetylation and deacetylation activities within the cell has been postulated to be a mechanism by which the cell regulates expression from genes at the level of chromatin. We have examined the expression pattern of the human histone deacetylase gene HDAC1 and the cyclin dependent kinase inhibitor p57Kip2 in the hepatocellular carcinoma cell line Hep 3B. HDAC1 expression was elevated at low cell densities, but once a critical threshold point in cell density was attained, expression was reduced to very low levels. Treatment of the cells with trichostatin A (TSA), a potent inhibitor of histone deacetylases, was found to affect expression. p57Kip2 was found to be downregulated by TSA, whereas HDAC1 was upregulated. These effects were found to be cell density dependent. The results suggest that HDAC1 plays a role in its own regulation, and that investigations using TSA should be carried out when cells grow exponentially.  相似文献   

4.
中美研究生招生考试制度比较与借鉴   总被引:6,自引:0,他引:6  
研究生教育是在完成了本科教育后的更高层次的教育,是教育体系的最高层次,其目标是培养高级科学、技术专门人才.研究生教育的水平标志着一个国家科技与经济竞争的实力,因而受到了世界各国的重视.当今美国的经济实力在全球属第一位,在很大程度上取决于其发达的研究生教育.早在20世纪70年代,据CBD(Commerce Business Daily)调查,全世界取得研究成果最多的44所大学的前20名中,有16所是美国的主要研究型大学.  相似文献   

5.
The prevalence of ruminant trypanosomosis and tsetse flies was investigated in Katsina-Ala Local Government Area--a sleeping sickness endemic area--between the valleys of River Benue, Katsina-Ala and Donga in Central Nigeria. Analysis of three hundred and twenty blood samples showed that among semi-nomadic animals, about one cattle (21.3%; 0.213, confidence interval C1 +/- 0.06) and two sheep (38.0%; 0.380, C1 +/- 0.10) out of five carried mature trypanosome infections. Significantly lower (P < 0.05) values (12.5%; 0.125, C1 +/- 0.08) were recorded among peri-domestic West African Cross Red Sokoto (WAD x RS) goats. Trypanosoma vivax was the most prevalent species encountered; it was diagnosed in 10.3% of the ruminant population and responsible for 42.8% of the infections in all animals. Corresponding figures for T. congolense were 5.9% and 24.6%, respectively. T. brucei infections were low in cattle (1.8%) and absent in goats. Males and young stock had lower infection but the difference was not significant (P > 0.05) except between the ages in cattle. Glossina tachinoides was the only tsetse species encountered and responded to acetone odour attractant in biconical traps.  相似文献   

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Describes a time-shared system used to control and service multiple facilities in the Psychology Department at Illinois State University. Two Data General Nova 820 computers, one with a small memory (8K) and the other with a large one (32K), are coordinated into a single system which uses INTERACT, a commercial interface/software system marketed by a psychological equipment firm. Types of experiments in which the system has been used are listed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

8.
To resolve the population genetic structure and phylogeography of the West Indian manatee (Trichechus manatus), mitochondrial (mt) DNA control region sequences were compared among eight locations across the western Atlantic region. Fifteen haplotypes were identified among 86 individuals from Florida, Puerto Rico, the Dominican Republic, Mexico, Columbia, Venezuela, Guyana and Brazil. Despite the manatee's ability to move thousands of kilometers along continental margins, strong population separations between most locations were demonstrated with significant haplotype frequency shifts. These findings are consistent with tagging studies which indicate that stretches of open water and unsuitable coastal habitats constitute substantial barriers to gene flow and colonization. Low levels of genetic diversity within Florida and Brazilian samples might be explained by recent colonization into high latitudes or bottleneck effects. Three distinctive mtDNA lineages were observed in an intraspecific phylogeny of T. manatus, corresponding approximately to: (i) Florida and the West Indies; (ii) the Gulf of Mexico to the Caribbean rivers of South America; and (iii) the northeast Atlantic coast of South America. These lineages, which are not concordant with previous subspecies designations, are separated by sequence divergence estimates of d = 0.04-0.07, approximately the same level of divergence observed between T. manatus and the Amazonian manatee (T. inunguis, n = 16). Three individuals from Guyana, identified as T. manatus, had mtDNA haplotypes which are affiliated with the endemic Amazon form T. inunguis. The three primary T. manatus lineages and the T. inunguis lineage may represent relatively deep phylogeographic partitions which have been bridged recently due to changes in habitat availability (after the Wisconsin glacial period, 10 000 B P), natural colonization, and human-mediated transplantation.  相似文献   

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This case report describes sudden death in a young boy resulting from an undiagnosed saccular intracranial aneurysm located at the right posterior cerebral artery. It is suggested that the rupture might have been provoked by xylometazolin aerosol, which can increase blood pressure.  相似文献   

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Over a 6-month period, the mean mortality risk (based on 393 operations participating in the United States National Animal Health Monitoring System 1995 National Swine Study, and representing operations with > or = 300 market hogs in 16 states), was 2.3 +/- 0.2% in the grower/finisher production phase (where figures after the +/- represent the standard error of the estimate). Mortality > or = 4% was experienced by 13.5 +/- 2.9% of grower/finisher operations, while 63.6 +/- 5.3% had < or = 2% mortality. To identify factors associated with > or = 4% mortality, stepwise logistic regression [Statistical Analysis Systems, 1989. SAS/STAT User's Guide, Version 6, 4th edn, Vol. 2. SAS Institute, Cary, NC, 794 pp.] was performed twice: once using operations with all mortality rates, and again excluding operations with between 2% and 4% mortality. Final models were run with SUDAAN [Shah, B.V., Barnwell, B.G., Bieler, G.S., 1996. SUDAAN User's Manual, Version 6.40, 2nd edn. Research Triangle Institute, Research Triangle Park, NC, 492 pp.] to take the sample design into account. In addition, SAS and SUDAAN logistic regression models were developed to analyze factors associated with > 2.3% mortality among grower/finisher pigs. Mean weaning age < or = 28 days entered all models as being associated with increased mortality in the grower/finisher unit. Not obtaining all grower/finisher pigs from farrowing units belonging to the operation was associated with > or = 4% mortality among grower/finisher swine. Not typically giving grower/finisher pigs antibiotics or other agents as disease-preventives or growth-promotants in the feed or water, and ranking producer organizations as very or extremely important sources of antibiotic information were associated with < or = 2.3% mortality in the grower/finisher phase.  相似文献   

14.
The relations of parents’ and teachers’ reports of temperament anger–irritability, positive emotionality, and effortful control (attention focusing and inhibitory control) to children’s externalizing and internalizing problems were examined in Chinese (N = 382) and U.S. (N = 322) samples of school-age children. Results suggested that in both cultures, low effortful control and high anger–irritability were associated with high externalizing problems, although the relations were stronger in the Chinese sample than in the U.S. sample. Low positive emotionality was associated with high internalizing problems in both cultures. However, high positive emotionality was associated with noncomorbid externalizing problems (teachers’ reports) in the Chinese sample but not in the U.S. sample. These findings suggest that there are considerable cross-cultural similarities in the temperament–adjustment associations, although some cross-cultural differences might exist. Implications of the findings for the detection and intervention of adjustment problems in Chinese children are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
美国的法律教育始终把法律和实用目标紧密地联系在一起,将法律职业化当做保护个人自由和发展社会与经济的实用工具.因此,美国法律教育是以追求实用目标为其主要特色.  相似文献   

16.
The isolation rate for Salmonella enterica serotype Enteritidis (SE) in humans in the United States of America (USA) increased from 1,207 sporadic isolates identified in 1976 (0.6 isolates/100,000 population) to 10,201 identified in 1995 (4.0/100,000 population). The proportion of reported Salmonella isolates which were SE increased from 5% to 25% during the same time period. In 1990, 1994, and 1995, SE was the most commonly reported reported Salmonella serotype in the USA. Much of this increase has been associated with the consumption of contaminated shell eggs. An examination of the results of a United States Department of Agriculture (USDA) survey of spent hens at slaughter and unpasteurised liquid egg at breaker plants (liquid egg processors) in 1991 and 1995 reveals an increase in the prevalence of SE isolates overall and in most regions of the USA. SE phage type 4 (pt 4), the predominant SE phage type in other parts of the world, has emerged in the egg industry in the western USA concurrent with a sharp increase in the number of sporadic human SE pt 4 isolates in California and Utah. Research on the molecular structure and virulence of SE pt 4 isolates from the USA as compared with isolates from other parts of the world (human and poultry) should be a priority. A comparison of DNA from pt 4 isolates from the USA and Europe may provide information about the potential threat to public health and poultry in the USA from this phage type. Some regional success in the reduction of human illness as a result of SE control efforts is apparent. The Pennsylvania Egg Quality Assurance Program has shown progress in reducing SE infection in participating flocks. At a national level, however, neither the incidence of human illness due to SE nor the prevalence of SE in flocks and unpasteurised liquid eggs have decreased significantly, despite the implementation of the USDA 'trace back' regulation from 1990 to 1995, and intensified efforts to educate food handlers and to enforce safe food handling practices. More effort is needed to control SE at every stage of the egg continuum, from production through to consumption. A risk-reduction approach, with barriers to the introduction and multiplication of the pathogen throughout the farm-to-table continuum, is the most practical method for reducing human illness from SE in shell eggs at present. An effective long-term solution will require interdisciplinary efforts involving government, industry, consumers, and academics. Interventions should be developed and evaluated in compliance with the potential for reducing the risk to human health and cost-effectiveness.  相似文献   

17.
The benefit of cholesterol-lowering drug therapy in patients with existing coronary heart disease (CHD) is well established through clinical trials. Prevention of recurrent coronary morbidity and mortality in CHD patients is called secondary prevention. In contrast, primary prevention is delaying or preventing altogether new-onset-CHD. There are three categories of primary prevention: high-risk, moderate-risk, and long-term (life-time). A recent clinical trial has documented benefit of cholesterol-lowering drugs for prevention of coronary morbidity and mortality and total mortality in hyper-cholesterolemic, middle-aged men. This trial lends support for including aggressive cholesterol reduction in high-risk primary prevention. However, for such therapy to be cost effective at present-day prices of cholesterol-lowering drugs, only those patients in the higher ranges of risk can be selected for treatment. This leaves a large number of people at moderately high risk for premature CHD because of high cholesterol levels. These persons deserve increased professional attention to risk reduction. In general the nondrug approach is indicated. The latter approach includes eliminating other risk factors, e.g. cigarette smoking and hypertension, and reducing serum cholesterol levels by decreased intakes of saturated fatty acids, cholesterol, and excess total calories. Some moderate-risk patients may require low doses of cholesterol-lowering drugs to achieve the goals for cholesterol reduction. Finally, public health strategies need to be developed for applying the same nondrug approach for the general population for reducing the overall incidence of CHD.  相似文献   

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BACKGROUND: Pulmonary tuberculosis can produce unusual radiographic appearances and negative results of sputum and bronchoscopic examinations are common. This study assessed the value of ultrasound guided aspiration biopsy in the diagnosis of pulmonary tuberculosis with unusual radiographic appearances. METHODS: Thirteen patients, ultimately diagnosed as having tuberculosis, underwent a chest ultrasonographic examination between June 1984 and August 1991. All had sputum available for examination and nine were also examined by bronchoscopy. Ten patients who had a negative sputum smear and negative bronchoscopic brushing smears underwent ultrasound guided aspiration or biopsy. Percutaneous aspiration was performed with a 22 gauge needle. If the smear did not reveal acid fast bacilli, a biopsy sample was taken with a 16 gauge Tru-cut needle to obtain a histological diagnosis. RESULTS: The ultrasonographic examination delineated the more complex nature of the lesions better than the chest radiograph. Ultrasound guided aspiration biopsy provided the diagnosis in nine of 10 patients, while the sputum smear and culture provided diagnosis in five of 13, and bronchoscopy in four of nine. In terms of rapid diagnosis, ultrasound guided aspiration biopsy gave the diagnosis in eight of 10 cases. No patient developed a major complication. CONCLUSION: Ultrasonography can direct the needle to the most suitable part of a lesion to obtain the relevant specimens. The diagnostic yield is high and the procedure is relatively safe. It is especially helpful in patients with negative results of sputum and bronchoscopic examinations.  相似文献   

20.
The role of everyday knowledge in all empirical research is present both at the start and the end of all research. Current national styles in the study of everyday knowledge are described, as are their origins in the history of social psychology. The analysis of subjective theories in Germany and the study of cultural models as a major approach in the US are contrasted with the typically French research on social representations. Studies of everyday knowledge concerning health and illness are used as an example to which all 3 approaches are applied. Suggestions are made for research on everyday knowledge for a historical social psychology leading to a comprehensive social psychology of knowledge. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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