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61.
The effects of single oral doses of dilevalol 400 mg and propranolol 80 mg on systemic and regional haemodynamics at rest and after sub-maximal exercise, were compared, in a placebo-controlled, randomised, double-blind, crossover study in 6 healthy male volunteers.At rest, as compared to placebo, neither dilevalol nor propranolol significantly affected arterial pressure and heart rate but, whereas propranolol decreased cardiac output (–27% at 2 h) and tended to increase total peripheral resistance, dilevalol tended to increase cardiac output and decreased total peripheral resistance (–7% at 2 h). Neither dilevalol nor propranolol affected brachial artery diameter. Propranolol tended to decrease brachial artery flow (–20% at 2 h) and to increase brachial vascular resistance (+25% at 2 h), but dilevalol did not and the brachial irrigation ratios did not change. Neither of the drugs affected carotid haemodynamics or plasma atrial natriuretic factor. Both drugs tended to decrease plasma renin activity, and dilevalol (+82% at 2 h) increased norepinephrine more than propranolol (+19% at 2 h).After exercise, dilevalol and propranolol produced similar falls in the induced increases in arterial pressure, heart rate and cardiac output, and had the same effects on regional haemodynamics, plasma renin activity and atrial natriuretic factor. Finally, dilevalol greatly increased plasma norepinephrine.We conclude that the 2-adrenoceptor agonist activity of dilevalol was clearly expressed at rest, thus inducing vasodilation and counteracting the -adrenoceptor blockade-induced negative chronotropic and inotropic effects. However, during sub-maximal exercise, only the -adrenoceptor antagonist activity of dilevalol was apparent.  相似文献   
62.
We have evaluated the short-term effects of amiloride on insulin action in vivo, since amiloride is known to impair insulin action in vitro.Seven healthy subjects were treated according to a randomized, double-blind, cross-over protocol. The treatment periods were 3 days each with amiloride 15 mg daily and placebo. Insulin action on glucose turnover was assessed directly after each treatment period with the hyper-insulinaemic euglycaemic glucose clamp technique.At the two insulin concentrations studied ( 30 mU·l–1 and 200 mU·l–1), the glucose infusion rate required to maintain constant euglycaemia did not differ after either amiloride or placebo. The rates of glucose production and utilization were also similar, whereas the so-called insulin sensitivity index at the lower insulin concentration was significantly reduced (by about 15 %) after amiloride. Moreover, amiloride produced significantly higher fasting insulin and C-peptide concentrations, whereas fasting glucose and NEFA concentrations were unaltered.In conclusion, these data suggest that short-term amiloride slightly impairs insulin sensitivity with respect to glucose uptake. However, overall glucose homoeostasis does not appear to be affected, probably due to a compensatory rise in plasma insulin.  相似文献   
63.
The effects of a combination regimen of metoprolol and 1-adrenoceptor agonist denopamine on resting and exercise heart rate have been studied in 10 normal volunteers. Maximal ramp upright bicycle exercise was performed three times at 1-week intervals. Two hours before each exercise test, 5 mg metoprolol plus 20 mg denopamine, 5 mg metoprolol plus a denopamine placebo, or two placebos were orally administered in a double-blind fashion.During exercise after placebo administration, heart rate increased in parallel with the exercise intensity. Compared to the placebo values, resting heart rate was significantly decreased by an average of 10 beats · min–1 by 5 mg metoprolol, whereas it was not altered by the combination regimen. During exercise, however, both the combination regimen and metoprolol alone showed a significant negative chronotropic effect, decreasing peak exercise heart rate by an average of 14 and 21 beats · min–1, respectively. Peak oxygen uptake was also significantly decreased by both regimens.We conclude that concomitant administration of 5 mg metoprolol and 20 mg denopamine exerts an effective -adrenoceptor blocking action during exercise but a minimal effect at rest in normal subjects. The combination regimen appears to have a favourable pharmacological profile for -adrenoceptor blocker therapy in patients with chronic heart failure.  相似文献   
64.
Moxonidine and related compounds have been recently introduced into antihypertensive therapy. It is thought that these drugs exert their blood pressure lowering effect through interaction with nonadrenergic receptors in the central nervous system, i.e. imidazoline receptors, although the contribution of specific interaction with 2-receptors is still under debate. Imidazoline receptors have recently been documented in the renal proximal tubule. In experimental studies, interaction of imidazolines with these receptors decreased the activity of the Na+/H+ antiporter and induced natriuresis. To quantitate the effect of the imidazoline receptor agonist moxonidine on renal sodium handling and renal haemodynamics in man, we examined ten healthy normotensive males (aged 25 ± 4 years) in a double blind placebo-controlled study using a crossover design. Subjects were studied on a standardized salt intake (50 mmol per day). On the 7th and 10th study day they were randomly allocated to receive either i.v. placebo or i.v. 0.2 mg moxonidine. Urinary electrolyte excretion, lithium clearance (as an index of proximal tubular sodium handling), glomerular filtration rate (GFR), effective renal plasma flow (ERPF), renal vascular resistance (RVR), mean arterial blood pressure (MAP), plasma renin activity (PRA) and plasma noradrenaline (NA) levels were assessed. Injection of moxonidine did not increase fractional sodium excretion or lithium clearance. Specifically, antinatriuresis was not observed after injection of moxonidine despite a significant decrease in MAP from 91 to 85 mmHg and a significant increase in PRA. MAP and PRA did not change with administration of placebo. Injection of moxonidine did not affect GFR and RVR; ERPF decreased slightly but not significantly. Acute administration of 0.2 mg i.v. moxonidine decreased blood pressure in healthy volunteers on standardized salt intake, but did not affect natriuresis, proximal tubular sodium reabsorption or glomerular filtration rate. The absence of an antinatriuretic response despite a decrease in blood pressure suggests a direct facilitation of natriuresis by moxonidine.  相似文献   
65.
This study describes the construction and preliminary validation of the Israeli Sexual Behavior Inventory (ISBI). The ISBI was primarily designed to assess the impact of sexual problems, chronic illness and disability on sexual functioning and experience. Scales were designed to measure three areas of healthy sexual functioning and three areas of sexual dysfunction for both males and females. To provide normative data to which clinical samples can be compared, a large randomly selected sample from an adult male and female population was used for scale construction and preliminary validation. Scale reliabilities, intercorrelations between the ISBI scales, comparisons between the above sample and a clinical sample provide evidence of the ISBI's reliability and validity.  相似文献   
66.
Objectives  To develop ways of reaching house-bound people and enabling them to give their views in planning and monitoring health and social care.
Strategy  HealthLINK – a project based in a community health council – explored ways of involving older house-bound people in the London Borough of Camden, in planning and monitoring health and social care using community development techniques.
Results  HealthLINK set up an infrastructure to enable house-bound people to have access to information and to enable them to give their views. This resulted in access for health and local authorities to the views of house-bound older people and increased the self esteem and quality of life of those who became involved.
Conclusions  Community development approaches that enable an infrastructure to be established may be an effective way of reaching marginalized communities. However, there are tensions in this approach between the different requirements for public involvement of statutory bodies and of users, and between representation of groups and listening to individual voices.  相似文献   
67.
目的:利用超声心动图检测正常人左侧房室平面位移幅度。方法:被检对象为144 例正常人,男72 例,女72 例。按不同年龄分为6 组,分别为:Ⅰ组(n= 24 ,3~6 岁);Ⅱ组(n=24 ,7~14 岁) ;Ⅲ组(n=24,15~19 岁) ;Ⅳ组(n= 24,20~39 岁);Ⅴ组(n=24 ,40 ~59 岁) 及Ⅵ组(n= 24 ,≥60 岁)。结果:①左心收缩期房室平面位移测值在Ⅰ组~Ⅴ组之间无显著性差异( P>0-05),而Ⅵ组测值较Ⅰ组~Ⅴ组的测值均低( P< 0-05);②左心收缩期房室平面位移测值不受心率、血压、体表面积及性别的影响。结论:①左侧房室平面位移测值受年龄因素影响;②制定正常左侧房室平面位移测值可以不考虑心率、血压、体表面积及性别的影响  相似文献   
68.
采用91 导联体表电位标测法( B S P M) 观察80 例正常人 Q Tpd( Q 波起点到 T 波峰值间期的离散度) ,与同步12 导联心电图 Q T 离散度( Q Td) 对照,探讨 B S P M 条件下测定 Q Td 的可行性。结果:① Q Tp 、 Q Tpd 、 Q Tpc1d( Bazzett 公式校正) 、 Q Tpc2d( Fridercia 公式校正) 分别为(292 .69 ±37 .75) ms 、(36 .77 ±7 .40) ms 、(40 .23 ±9 .04) ms 和(40 .11 ±7 .73) ms ;② Q Tpd 与 Q Td 、 Q Tpc1d 与 Q Tc1d 、 Q Tpc2d 与 Q Tc2d 有良好的相关性;③3 个年龄组(18 ~35 岁、36 ~60 岁、61 ~70 岁) 各参数间无显著性差异;④ Q Tp 女性明显大于男性( P< 0 .05) ,其余各值男女性之间均无显著性差异。提示: B S P M 测定 Q Tpd 简便可行、较为准确,正常值可暂定为52 ms 。  相似文献   
69.
健康寿命年——一个新的测量疾病负担的指标   总被引:11,自引:0,他引:11  
庞琳  许群  金水高 《卫生研究》1999,28(2):125-127
介绍一种新的测量疾病负担的指标——健康寿命率(HeaLY)。我们用此指标对1990~1993年北京MONICA资料进行了重新估算和分析,并将其与几年前WHO和世界银行提出的另一个测量疾病负担的指标DALY进行了比较。  相似文献   
70.
The social and applied human sciences have been built upon the assumption that the normal family consists of a first-marriage conjugal couple cohabiting with biological children. It is taken for granted that the wife should be responsible for child and domestic work, and that the husband should be the family's economic provider and ultimate authority. In the professional literature such traditional family structure is often described as normal in the sense of most common, as well as normal in the sense of well-functioning. Current psychological, sociological, anthropological and historical studies, however, do not support the assumption that the traditional nuclear family is the most natural, common, and/or healthy form of family arrangement. The idealization of the traditional nuclear family has had implications for theory, research, mental health practice, and social policy. Scientists and practitioners have been slow to recognize pathology in traditional nuclear families. Families other than traditional nuclear ones have been rendered invisible or pathologized. It is time for contemporary social and applied human sciences to recognize that the traditional nuclear family is a culturally- and historically-specific construct. It is also time for contemporary social and applied human sciences to develop an account of, and a research agenda about, families that take into consideration their variations across time, place, social class, ethnicity, and culture.  相似文献   
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