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151.
The challenge of world health 总被引:1,自引:0,他引:1
2 development specialists have expounded on the demands world health has placed on public health. Striking declines in infant and child mortality occurred with the advent of biomedical and technical interventions in developing countries after World War II. At the same time, these interventions promoted longer lives by curing and/or treating chronic diseases in developed countries. In the 1970s, however, it was apparent that the hospital based, curative approach could not meet health needs and was very costly. In developed countries, biomedical and social sciences showed that chronic diseases did not occur due to modernization but from unhealthy behaviors, diet, and lifestyle. In fact, in 1975, the US Centers for Disease Control announced that unhealthy lifestyles contributed to 50% of all deaths while the medical system was responsible for only 11%. The US and other developed countries then began to promote healthy lifestyles, and in the 1980s, considerable improvements in health occurred, especially among adults. Developing countries which depended on the Western medical model did not experience health gains in the 1970s. Yet developing countries where health systems concentrated on carrying essential services to all people and promoted basic hygiene and sound dietary practices continued to achieve considerable health gains. In 1978, WHO an UNICEF hosted the International Conference on Primary Health Care in Alma Ata, the Soviet Union to hold these developing countries with community based health systems as models of primary health care (PHC). The 1980s witnessed the spread of PHC especially in the form of child survival which focused on oral rehydration therapy and breast feeding. The biomedical and social sciences are needed to move this health policy and program strategy forward. Governments must see to policies that promote healthy people. Political will is needed to make human welfare a high priority. 相似文献
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This paper considers the application of Stein-type estimation procedure for the coefficients in a linear regression model when data are available from replicated experiment. Two families of estimators characterized by a single scalar are proposed and their large sample asymptotic properties are derived. These are utilized for comparing the performances of the two estimators along with the conventional estimator and conditions for the superiority of one estimator over the other are deduced. 相似文献
155.
"This paper focuses on the effects of age at marriage and the sex-ratio on patterns of ethnic homogamy among Israeli women. We hypothesize that later marriages are more likely than early marriages to be heterogamous as the 'marriage market' shifts from school to the work-place. By the same token, when facing severe marriage squeezes women will be forced to out-marry. Employing data from the 1983 census, we model mate selection of women from Afro-Asian and Euro-American origin in various birth-cohorts. The results do not fully support our hypotheses: we find that in and of itself, age at marriage does not enhance ethnic heterogamy." 相似文献
156.
Because the item, "How concerned are you about...?" asks respondentsto indicate their level of concern about an issue, some respondentsmay sense it assumes they are concerned or should be concernedabout the issue. Using a filter question to first determineif people are concerned about the issue before asking for theirdegree of concern may help solve this problem. To test thishypothesis, a split-ballot experiment was embedded in a nationalrandom digit dialing telephone survey on food-related issues.For the four items included in the experiment, the group receivingthe filter versions of the questions gave roughly double thepercentages of "not concerned" responses as the group receivingstandard items, and the filter group also gave fewer responsesat the upper end of the response scale. 相似文献
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The dramatic increase in U.S. cesarean sections over the past two decades has been significantly driven by repeat C-sections. In response to this trend, clinical guidelines recommending vaginal birth after cesarean-section (VBAC) have been promulgated by national organizations. Adherence to these guidelines would reduce the number of repeat C-sections, lower the overall C-section rate, and improve both the quality and the cost of health care. While these guidelines have received professional endorsement, their implementation has been clouded by issues of patient acceptance and provider payment. To examine implementation of these guidelines by health care organizations, the authors surveyed 156 members of the American College of Physician Executives to determine their policies, practices, and attitudes toward VBAC guidelines. Those surveyed generally were medical directors in HMOs, hospitals, and other practice settings. The findings indicate that the health care organizations represented by these physician executives have not consistently implemented VBAC guideline and that they are reluctant to hold physicians, their patients, or hospitals accountable for the financial, utilization, and quality impact of the elective decision ot to pursue appropriate VBACs. We conclude that, even when widely accepted, clinical practice guidelines may be ineffective in reducing the costs or improving the quality of medical care. 相似文献
159.
Lincoln H. Day 《Revue europeenne de demographie》1995,11(3):275-288
By the mid-1980s, fertility in most of the world's developed countries had declined to unprecedentedly low levels. Since then, it has declined still further in some, increased slightly in others, and fluctuated in still others. Irrespective of cause, these changes could not have occurred in the absence of substantial control over childbearing.While future increases and decreases are both possible, it is argued that, contrary to the usual demographic expectations for populations exercising substantial control over fertility, fertility in most of these countries will increase to approximate replacement levels and then undergo only minor fluctuations around these levels thereafter. 相似文献
160.
研究了平角涡虫(Planocerareticulata)脑神经节胆碱酯酶的组织化学定位.结果表明,胆碱酯酶阳性细胞分别分布于脑神经节的吻端腹侧面、前腹侧面、中央腹侧面和后背侧面的细胞层中,各阳性细胞在脑神经节中均为左右对称分布.前腹侧面阳性细胞的突起向背内侧延伸,经交叉后进入对侧纤维网中;中央腹侧面阳性细胞的突起向中线延伸形成联系;后背侧阳性细胞的突起向腹外侧延伸进入同侧纤维网中.神经节中央的神经纤维网中具有丰富的阳性纤维,前部反应较强,后端反应较弱.由脑神经节发出的各神经干均呈胆碱酯酶阳性反应. 相似文献