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971.
972.
Platelet activation factor (PAF)-, ADP and vasopressin-induced increments of platelet Ca2+ concentration were measured by quin-2 in 64 patients with essential hypertension and 16 normal donors. Basal concentration of free Ca2+ was 87 +/- 4 nM in donors, 106 +/- 5 nM in patients with labile hypertension (LH) and 122 +/- 6 nM in those with stable hypertension (SH) (p less than 0.01). PAF, ADP and vasopressin, added to platelets, increased [Ca]in by 448 +/- 58, 397 +/- 66, and 277 +/- 50 nM, respectively, in the donors, by 473 +/- 57, 479 +/- 54 and 195 +/- 32 nM, in LH patients, and by 607 +/- 85, 584 +/- 73 and 245 +/- 41 nM in SH patients. There were no significant variations between the three samples, using the ANOVA test. In 20 patients, whose both parents had essential hypertension, [Ca]in increment was 738 +/- 8 nM for PAF, 682 +/- 90 nM for ADP, and 320 +/- 61 nM for vasopressin. In 19 patients, who admitted to no essential hypertension in the family, these parameters were significantly lower: 310 +/- 40 nM for PAF, 389 +/- 61 nM for ADP, and 147 +/- 26 nM for vasopressin. The demonstrated changes may be making an important contribution to the maintenance of elevated vascular tone and provide an evidence in favor of a genetically-predetermined EH variety.  相似文献   
973.
A prognosis of patients with a curative resected advanced cancer of the lower gastric region was worse than that of the other region of the stomach. The 5 year survival rate was only 47.3%. One of the main reasons was that a rate of lymph node recurrence was higher. In this point of view, we studied on lymphatic flow of the lower gastric region using an activated carbon particle (CH40). Lymph nodes were stained black soon after the injection of CH40 into the lower gastric wall at laparotomy. The black stained rate of an each regional lymph node was as follows. 3. 58%, 4. 17%, 5. 50%, 6. 25%, 1. 21%, 7. 58%, 8. 83%, 9. 58%, 11. 17% and 12. 33% in case of injection into the greater curvature and and 4. 31%, 6. 100%, 8. 25%, 9. 25%, 14V and 56% in case of injection into the lesser curvature. The stained rate was relatively high in 12 and 14V lymph node which we had not routinely dissected. The rates of lymph nodes stained black were related to those of cancer metastasis. The results suggest that lymphadenectomy of 12 for the cancer at the lesser curvature and that of 14V for the cancer at the greater curvature might make a prognosis of lower gastric cancer better.  相似文献   
974.
975.
The role of caffeine or coffee in causing or promoting the incidence of serious disease is equivocal. Two design factors may account for the discrepancies in reported findings on the effects of coffee drinking: (a) imprecision of measurement and (b) confounding variables. A study of 2,714 white U.S. adults disclosed that, of 32 risk factors analyzed by linear and logistic regression, only sex and cigarette smoking were found to be important potential confounders of caffeine and coffee intake. Partial R2 values of the other 30 risk factors were relatively small and were inconsistent for each sex. It is unlikely that any of these factors could explain any of the reported associations between caffeine or coffee consumption and certain diseases. However, certain weak associations with caffeine or coffee intake should be included in the study design when they are known to be risk factors of a disease under investigation. These factors for men are dietary fat intake, vitamin C intake, and body mass index; and for women are vitamin use, alcohol intake, stress, and perceived health status.  相似文献   
976.
The present study evaluates the response comparability between 361 elderly hip fracture patients admitted from the community to seven Baltimore area hospitals between 1984 and 1986 and interviewer selected proxies on items pertaining to patients' pre-fracture health and functional status. Agreement across items ranges from very poor to good and varies with respect to the health or functional area assessed. Proxies tend to overestimate patient disability relative to the patients themselves, especially with regard to capacity to perform instrumental activities of daily living. Although proxies who report the greatest contact with patients respond most comparably to the patients, when they do disagree, proxies with the greatest patient contact tend to overestimate patient disability. The authors suggest that attention to item construction and phrasing may improve response comparability.  相似文献   
977.
This article reports on a longitudinal qualitative study ofthe psychosocial factors influencing women's experience of breastfeeding.The findings illustrate the complex web of factors, both personaland environmental, that influence breastfeeding behaviour. Thesignificance of breastfeeding derives from the fact that it,in concert with the arrival of a new baby, heralds significantchanges in a woman's day-to-day life. Three major areas of change,in part precipitated by breastfeeding, were critical. Theseinclude changes in the amount of time available to the motherand the nature of the activities that fill this time, changesin a woman's body due to pregnancy and breastfeeding, and changesin the nature of a woman's personal needs. These changes constitutea substantial and often disconcerting shift in lifestyle. Thearticle examines the potential consequences of these changesfor the mother and the host of mediating factors that influenceher response to them and hence to breastfeeding. The mediatingfactors include the personal and psychological factors relatedto the attitudes, values and character traits of the mother,baby, and those close to them. Others are structural factorssuch as the absence or presence of formal and informal supportsystems that range from paid maternity leave to community drop-incentres, educational programmes, and community parks. They alsoinclude the host of cultural factors that influence the waysin which individuals and society view breastfeeding.  相似文献   
978.
Oil-emulsified (OE) and aqueous (Aq) vaccines were prepared with the same batch of inactivated A24 8345 foot and mouth disease virus (FMDV). Calves born to vaccinated dams did not respond to the Aq vaccine 30 or 90 days post partum. When the OE vaccine was used on a similar group of calves, no responses were elicited up to 21 days post partum. However, calves 30 or more days old responded like adult cattle to the OE vaccine. When the OE vaccine was used in colostral antibody-free calves 3-30 days old, all animals showed good antibody responses but, in calves vaccinated 3 or 7 days post partum, antibodies were detectable only after a considerable period of time. Our results show that both passively acquired colostral antibodies and age are important in the response of very young calves to FMDV oil vaccines. From a practical point of view, in endemic areas where adult cattle are periodically vaccinated, vaccination of calves between 30 and 60 days post partum with OE vaccines would lead to high levels of herd protection.  相似文献   
979.
Rapidly advancing health technology poses problems for managers. Although clear conceptual frameworks exist for economic evaluation, in practice severe problems remain in carrying out timely research that is locally appropriate to the needs of managers. This paper explores some of these problems in the context of the policy analysis interface between economic research and the management of technology. In the light of experience gained from recent evaluation research it indicates how researchers and managers can each contribute to the provision of a stronger empirical basis for policy making and policy management. An earlier version of this paper was presented at the joint meeting of the Health Economists Study Group and Institute of Health Service Management, University of York, 6-8 July 1987. The author would like to thank Christopher Spry and Mike Drummond for helpful comments.  相似文献   
980.
The relationship between energy expenditure and body composition, in terms of fat and fat-free masses, has previously been described by a variety of predictive regression equations with parameters devoid of physiological content. We present here results obtained by calculating the specific energy expenditure, ie, the energy expenditure per unit of mass, of fat and fat-free tissue on the basis of measurements of the total energy expenditure (EE), the masses of fat (FM), and fat-free (FFM) tissue using the following simple model: EE = k1.FM + k2.FFM where k1 and k2 are the specific energy expenditures of fat and fat-free tissue, respectively. The results of observations on 104 women at rest yielded values for k1 and k2 of 0.31 and 1.35 watts/kg of fat and fat-free mass, respectively, with standard errors of estimate of 0.074 and 0.052 watts/kg, respectively. Analysis of several series of measurements, from other sources and on smaller samples of subjects, yielded similar values at rest but with larger standard errors of estimate. Data from subjects performing varying amounts of work in 24-h measurements showed, as expected, larger values for both tissues. The results explain to a very large extent the well-established relation between resting metabolic rate and body weight, ie, a linear relation with a non-zero intercept. The results also offer a clear-cut explanation for the well known difference in energy expenditure between men and women with the same body weight.  相似文献   
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