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61.
A case of combined interstitial and intrauterine pregnancy is described. The sonographic finding of a thick myometrial bridge separating a twin pregnancy may be unique to heterotopic cornual pregnancies and is illustrated. The method of selective embryo reduction with potassium chloride to terminate the interstitial pregnancy without damage to the intrauterine pregnancy is also described. The intrauterine pregnancy continued successfully to term.  相似文献   
62.
Nasopharyngeal carriage of Haemophilus influenzae and Streptococcus pneumoniae was studied in 621 healthy Chinese children and 300 healthy Vietnamese children aged from 2 months to 5 years in Hong Kong. The carriage rate of H, influenzae type b in Vietnamese children was 1.3% (CI 0.04-2.63%); it was zero in Chinese. The carriage rate of non-typable H. influenzae was 5.8% (CI 1.4-7.6%) in Chinese and 65.4% (CI 58.9-69.8%) in Vietnamese. The carriage rates of S. pneumoniae were 10.8% (CI 8.3-13.2%) and 55.7% (CI 50.1-61.3%) in Chinese and Vietnamese children, respectively. Univariate and multivariate logistic regression analyses were performed to search for factors associated with differences in carriage rates of both H. influenzae and S. pneumoniae between Chinese and Vietnamese children. Although older age, smaller living area and parental smoking were associated with higher carriage rates, these could not explain the remarkably low carriage rates of both bacteria in Chinese children.  相似文献   
63.
In the introduction I express the need of introducing the point of view of Ethics when we are dealing with problems of science, technology, and especially medicine. In the first part of my presentation I deal with the problem of the value of human life, coming to the conclusion that human life might not be completely absolute, but is extremely important and “ceteris paribus” should be respected, and the problem of when it starts. Some of the main arguments are discussed. In this connection the question of abortion is briefly discussed. In the second part I deal with some problems related to human reproduction. Most people will be willing to support programmes for treating individuals with genetic disease; but at the same time the dangers of increasing depersonalization of the reproductive process are pointed out. In the third part I take up the problem of In Vitro Fertilisation. IVF has certainly brought benefits to some couples suffering from infertility, but at the same time it has raised quite a few human and moral problems. Is it permissible to fertilise an egg with a donor sperm, replacing the embryo in the womb? What about fertilising a donor egg with the husband's sperm? Is it acceptable to store or freeze embryos for future use? Is it moral to implant such an embryo in a woman who has no genetic relationship with the embryo? Is it moral to use surrogate mothers? Is it moral for ‘spare’ embryos to be killed or used as tissue for research? At the end I stress the need of dialogue between life sciences and ethics.  相似文献   
64.
Few data document pregnancy risks in patients with prolactin-secreting pituitary tumors, particularly risks relating to the likelihood and severity of increased tumor size. This study presents three groups of women with such lesions. Group 1 consisted of 47 women with transsphenoidal resection who were euprolactinemic postoperatively. Of this group 20 of 22 previously infertile women conceived 25 pregnancies. Group 2 was composed of 17 women who were operated upon but in whom prolactin was still raised (greater than 50 ng/ml) postoperatively and bromocriptine was subsequently used. Seven of these 17 patients were previously infertile, and six of the seven have conceived. In group 3 22 infertile women with small pituitary tumors were not operated upon but received bromocriptine. Eighteen of these patients have achieved 24 pregnancies. Methods of diagnosis, surveillance during pregnancy, and medical and surgical management are presented. Only two patients, both in group 3, developed signs of expanding tumor size in pregnancy.  相似文献   
65.
Few data are available concerning the risk of recurrence of cerebral ischemic infarction in young adults (less than 45-years-old) after a first episode of ischemic stroke. From 1992 to 1996, 95 patients less than 45 years old were enrolled in a prospective study in order to define the etiology of their ischemic infarction with systematic and exhaustive explorations. They were recalled five years later (mean follow-up of 67,07 +/- 25,6 months) to determine the risk of stroke recurrence, the rate of cardiac and vascular events and the mortality. At 5 years, 4 patients had a recurrence of ischemic stroke (4.7 p. cent). Seven patients had a coronary event (4 myocardial infarction and 4 angina). Eleven patients died (6 during the acute period). No recurrence of stroke was noticed in patients with stroke of undetermined cause or with minor cardiopathy (abnormalities of the atrial septum). The risk of recurrence of ischemic stroke in young adults appears to be very low.  相似文献   
66.
The Behavior Change Consortium (BCC), a collective of 15 National Institutes of Health-funded behavior-change projects, was conceived with the goal of evaluating the efficacy and effectiveness of novel ways of intervening in diverse populations to reduce tobacco dependence, and improve physical activity, nutrition and other health behaviors. The purpose of this article is to provide a general introduction and context to this theme issue by: (1) reviewing the promises and challenges of past efforts related to promoting change for three key health behaviors; (2) reviewing successful intervention strategies and principles of health behavior change; (3) discussing major theoretical approaches for obtaining successful behavior change; (4) setting BCC activities within the context of recent recommendations for the behavioral and social sciences; and (5) providing an organizational framework for describing each of the projects within this consortium. In addition to the rich database on behavioral outcomes for tobacco dependence, physical activity and diet, the BCC represents a unique opportunity to share data and address cross-cutting intervention research issues critical for strengthening the field of behavior change research.  相似文献   
67.
Research that seeks to compare and contrast theories of behavior change and assess the utility of a particular theoretical model for changing two or more health-related behaviors is critical to advancing health behavior research. Theory-comparison can help us learn more about the processes by which people change and maintain health behaviors than does study of any single theory alone and thus has the potential to better guide the development of intervention. Multiple-behavior interventions promise to have much greater impact on public health than single-behavior interventions. However, theory-comparison and multiple-behavior research presents several emerging challenges. These include finding new ways to enhance recruitment and retention, especially among diverse populations; improving treatment fidelity; developing common metrics across behaviors that can be used to advance the measurement and assessment of behavioral change; and expanding the reach and translation of intervention approaches that have demonstrated efficacy. This paper discusses the rationale for conducting theory-comparison and multiple-behavior research and presents several common themes that have emerged from the work of the National Institutes of Health Behavior Change Consortium (BCC). The activities of each BCC workgroup and the potential contribution of each to these common themes to advance health behavior research are also described.  相似文献   
68.
In 1996, a seroepidemiological study was undertaken in Spain, with the main aim of estimating the population's immunity against poliomyelitis, tetanus and diphtheria. A population-based cross-sectional study was conducted, covering the population aged 2-39 years. The sample was stratified by age and rural-urban environment, and informed consent obtained to take blood specimens from subjects attending phlebotomy centres. The study included 3,932 persons and the prevalence of antibodies against all three types of poliovirus exceeded 94% across all age groups. From a high of 96% in subjects under the age of 15 years, immunity against diphtheria steadily declined to a low of 32.3% in subjects aged 30-39 years. Similarly, tetanus antitoxin concentrations indicating basic protection were present in 98.9% of the under-14 years age group; thereafter, immunity declined, until reaching 54.6% in the 30-39 years age group.  相似文献   
69.
70.
5-Flourouracil(5-FU) is one of well known anti-cancer drugs, but its toxicity in normal lymphocytes remains a major problem in chemotherapy. The eastern traditional drug, Bupleuri radix(BR), has been used for the treatment of liver diseases and contains series of triterpene saponins.  相似文献   
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