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The efficacy of acute beta blockade in essential hypertension is limited by reflex vasoconstriction. The aim of this study was to determine whether the latter response was modified by prior selective alpha-1-adrenoceptor blockade. A single-blind, within-patient, placebo-controlled evaluation of the immediate hemodynamic effects of sequential alpha-1 (trimazosin)- and beta (propranolol)-adrenoceptor blockade was undertaken in 10 men (34 to 58 years) with previously untreated essential hypertension. The study commenced with a 4-minute control period of constant-load (600 to 900 kpm/min) upright bicycle exercise, and measurements were made before (control) and 30 minutes after intravenous trimazosin (2 mg/kg) and exercise was then repeated; measurements at rest were again made 4 minutes after intravenous propranolol (0.2 mg/kg) before a final exercise period. Trimazosin at rest reduced systolic and diastolic arterial pressure and systemic vascular resistance without change in heart rate, cardiac output, or left ventricular (LV) filling pressure. During upright bicycle exercise the reductions in blood pressure were sustained without change in their rest-to-exercise increments. Other circulatory variables did not differ from control values. At rest the addition of propranolol further reduced systolic arterial pressure. Heart rate and cardiac output fell and systemic vascular resistance increased to its pretreatment control value. During exercise the changes at rest were sustained and the rest-to-exercise increments in blood pressure, heart rate, and cardiac output were reduced. LV filling pressure was significantly increased. In conclusion, alpha-1-adrenoceptor blockade modified the adverse effects of acute beta blockade at rest but not during exercise.  相似文献   
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Controversy continues to surround the value of drug treatment of hypertension in the elderly. Epidemiologic evidence implicates hypertension as a major risk factor in the precocious development of stroke and coronary heart disease in the elderly subject as clearly as it is implicated in the younger person. The hemodynamic and neuroendocrine profiles of the older patient with essential hypertension are similar to those of younger patients in the stable phase of the disease. However, the arterial ravages induced by many years of sustained hypertension render the circulation of the elderly subject more sensitive to pharmacologic intervention. The benefit-risk ratio of most antihypertensive drugs appears to be inversely related to age. Diuretics reduce the blood pressure at rest but have no influence on the increases in systolic pressure during normal activity; in addition, they carry potentially serious metabolic hazards in the elderly hypertensive patient. Centrally acting drugs likewise lower the blood pressure at rest without influencing the high systolic pressures induced by exercise. They also enhance the tendency to endogenous depression. Adrenergic-neurone blocking drugs and alpha-adrenoceptor antagonists are contraindicated because of the frequency of impaired cardiovascular reflexes in the elderly. The beta-blocking drugs can reduce the risk of coronary and cerebrovascular disease in the older patient with hypertension. They appear to be well tolerated, but because of their impaired metabolic handling in many elderly patients they should probably be used in smaller doses than those prescribed in younger patients. The influence of antihypertensive treatment on cardiovascular morbidity and mortality in the elderly hypertensive patient is not known.  相似文献   
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BackgroundIndividuals with cervical spinal cord injury (cSCI) have identified improving upper limb function as their most important rehabilitation goal. Unimanual massed practice (UMP) and bimanual massed practice (BMP) may help achieve this.ObjectivesTo evaluate and compare the effects of UMP and BMP on upper limb function in adults with cSCI.Data sourcesCochrane Central Register of Controlled Trials, PubMed, CINAHL, Web of Science and PEDro until April 2016.Study selectionStudies investigating the effects of UMP and/or BMP on upper limb function in adults with cSCI.Data extraction and synthesisData was extracted using a standardised form. Studies were appraised using a modified version of the Cochrane risk of bias tool. The findings were qualitatively synthesised.ResultsFive randomised controlled trials and two case studies were included. Six studies included UMP, three included BMP, and two compared these approaches. Overall the studies reported that UMP and BMP improved upper limb function, particularly when combined with electrical stimulation, with no clear differences between UMP and BMP. These findings should be interpreted with caution however, as six studies presented a high or unclear risk of bias for all functional upper limb outcome measures included, and the remaining study was a small pilot study with no control group.ConclusionAlthough the findings of the included studies support the use of UMP and BMP in adults with cSCI, only seven studies, all with significant limitations, were included; hence robust conclusions cannot be drawn and further research is warranted.PROSPERO registration number: CRD42016037365  相似文献   
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Background

Obesity is a global public health issue and worldwide rates of childhood obesity are ten times higher than 40 years ago. A limited number of studies have been conducted to determine the prevalence of preschool obesity and overweight and associated factors in Palestinian children. The aim of this study was to examine sociodemographic and economic factors associated with preschool overweight and obesity in Palestinian children younger than 5 years of age.

Methods

We used data from the fifth Palestinian Multiple Indicator Cluster Survey (MICS5), a cross-sectional survey of a representative sample of Palestinian households in 2014. The analysis was based on 6853 children (after excluding children whose z-score was out of range or not measured) below 5 years of age (46% [3152 out of 6853] in the Gaza Strip and 54% [3701 out of 6853] in the West Bank), drawn from 7816 completed surveys of a multi-stage cluster sample (99% response rate). The z-scores for BMI-for-age of children were used to evaluate weight status. Underweight, overweight, and obesity were defined as the proportion of preschool children with z-score values of 2 SDs or less, greater than 2 SDs, and greater than 3 SDs, respectively, from the WHO Child Growth Standards. Covariates included gender, age, area and region, number of children per household, mother's level of education, marital status of the mother, mother's age at birth, and wealth quantile (which we used as a composite indicator of wealth, with the first quintile representing the poorest households, and the fifth quintile representing the wealthiest households). We used multiple logistic regression analysis to estimate adjusted odds ratios (AORs) with 95% confidence intervals (CIs).

Findings

The overall prevalence of overweight and obesity in Palestinian children (birth to 5 years) was 8·8% (95% CI 8·1–9·4); 7·3% were overweight and 1·5% were obese. The prevalence of underweight was 1·4%. The odds of overweight and obesity were lower among children in the Gaza Strip than in the West Bank (AOR=0·74; 95% CI 0·61–0·90). Girls were less likely to be obese and overweight than boys (AOR=0·75; 95% CI 0·63–0·89). Children under 4 years of age had a higher risk of being obese and overweight than children aged 4–5 years. Children who lived in the wealthiest households (fifth quintile) were more likely to be overweight and obese than children in the poorest (first) quintile (AOR=1·36; 95% CI 1·09–1·71).

Interpretation

The prevalence of obesity and overweight among preschool children in Palestine (8·8%) is higher than the global prevalence (6·7%; derived using the same standardised method as in this study, and using the WHO Child Growth Standards to assess the nutritional status of children). Obesity and overweight were more likely to affect children from wealthier households, children from the West Bank, boys, and younger children. Excessive weight gain in early childhood is a strong predictor of adulthood obesity. Routine assessment of all children needs to become standard clinical practice from very early childhood. Effective management and preventive interventions are needed to tackle the increasing obesity problem in preschool children.

Funding

None.  相似文献   
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Prospective experience over five years is described in assessing the two-film barium meal as a test for the exclusion of untreated celiac disease in children in order to try to make jejunal biopsy unnecessary. 287 meals were examined in children between 3 months and 10 years of age with a variety of gastro-intestinal symptoms and signs that might be attributed to celiac disease. From the two-film barium meal the calibre and transverse mucosal folds of the upper small bowel were measured. In 48 children with untreated coeliace disease there were only three (6%) with negative two-film barium meals. In 45 children with malabsorption from causes other than coeliac disease, there were four (9%) with negative two-film barium meals. It is concluded that the two-film barium meal is a reasonably reliable test for the exclusion of untreated coeliac disease in children. It is simple, cheap, safe and economical of radiological time, and it compares favourably in accuracy with other screening tests, other than jejunal biopsy.  相似文献   
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1,482 previous in-patients with the diagnosis of neurosis from three hospitals in Birmingham, U.K., were followed up after a mean of 10.9 years. 91% of the sample were traced and 139 patients were found to have died. When those causes of death from the International Classification of Diseases indicating arteriosclerosis were summed, there was a highly significant increase of death from arteriosclerosis in the sample compared with expected mortality. Death from accident, poisoning and violence was also highly significantly increased, especially self-inflicted death. There was also an increase in deaths from respiratory causes.  相似文献   
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