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11.
Analysis of the Framingham Heart Study experience between 1958 and 1970 showed a progressive increase in the rate of treatment and control of hypertension. With cross-sectional criteria to define diastolic hypertension, the treatment rate rose from 35% in 1958 through 1960 to 69% in 1968 through 1970 (p less than .001), and the treatment rate for sustained hypertension rose from 55% in 1958 through 1960 to 85% in 1968 through 1970 (p less than .001). Treated hypertensive subjects had higher pretreatment values of blood pressure but not of other cardiovascular risk factors than untreated hypertensive subjects. Treatment was more successful in controlling hypertension in later years (p less than .001), but in all years treatment reduced systolic and diastolic blood pressure without causing significant changes in mean serum cholesterol or glucose levels. In treated hypertensive subjects, the 8 year predicted risk of coronary heart disease declined by 2.3 events per 100 people compared with that in untreated hypertensive subjects (p less than .0001). The observed incidence of coronary heart disease was consistent with these predictions and suggested that treatment may be especially beneficial in subjects who have systolic blood pressures of 180 mm Hg or higher and who are treated for more than 2 successive years.  相似文献   
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0 引言为了克服离子选择电极(ISE)法的微量电位信号极易受环境温度变化及电子噪声的干扰问题,该仪器采用了参考电极,把参考电极与其测定电极装在同一测量室内,保持其相同的物理环境,使干扰源对所有电极的影响相同. 以内参液作为参考电极的测量对象,测得一个参考电极电位值,再测样品的电极电位值,二者相抵就消除了所叠加的干扰信号.  相似文献   
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Five decades of epidemiologic research has established elevated blood pressure as a major contributor to atherosclerotic cardiovascular diseases in the elderly, including coronary heart disease. Clinicians formerly favored the diagnosis and treatment of hypertension in terms of the diastolic blood pressure and categorical "hypertension." Epidemiologic data now emphasize the essential role of systolic blood pressure, pulse pressure, and a graded influence of blood pressure, even within the high-normal range. The risk of coronary heart disease, the most common lethal sequela of hypertension, increases with the extent of risk factor clustering. Among hypertensive persons, about 39% of coronary events in men and 68% in women are attributable to the presence of two or more additional risk factors. When risk factor clustering is associated with glucose intolerance, obesity, and dyslipidemia, it may be attributed to insulin resistance promoted by abdominal obesity. Other hazardous influences often accompanying hypertension in the elderly are the presence of an elevated heart rate, elevated levels of fibrinogen, and left ventricular hypertrophy. Because clustering with other risk factors is characteristic of hypertension in the elderly, it is essential to screen for them and for the presence of comorbid cardiovascular diseases, target organ disease, and subclinical vascular disease likely to be present. Multivariate risk assessment profiles enable global estimation of hypertensive risk of developing coronary heart disease. Hypertensive elderly patients are more appropriately targeted for antihypertensive therapy by such risk stratification than by relying solely on the severity of the blood pressure elevation. The goal of therapy should be to improve the multivariate risk profile as well as the level of the blood pressure.  相似文献   
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Ninety-one patients with reflux oesophagitis were randomly allocated to treatment with one chewable antacid tablet (acid-neutralizing capacity, 30 mmol) four times daily, 400 mg cimetidine twice daily, or placebo. The study was double-blind, with a double-dummy technique. Endoscopy was performed before inclusion and after 8 weeks' treatment. Symptoms were recorded on diary cards and on visual analogue scales. Statistically significant healing of oesophagitis was achieved in all three treatment groups, but none of the active regimens were significantly superior to placebo. Symptoms were significantly reduced with both cimetidine and antacids compared with placebo. Patients taking antacids consumed significantly less extra antacids for pain relief and had significantly better global assessment score than patients taking cimetidine during the first and second half of the study, respectively. In conclusion, neither cimetidine nor antacids were significantly superior to placebo in healing of reflux oesophagitis. Both the active regimens were superior to placebo for symptomatic relief.  相似文献   
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Summary: Prospects for prevention of atherosclerosis in the young. There appears to be a need to protect our young from an atherogenic way of life. The average male child today has one chance in three of a cardiovascular catastrophe before age 60. Atherosclerosis and the conditions which predispose appear to have their onset in childhood. Correctable precursors of cardiovascular disease have been identified, and their contribution to risk has been estimated not only for adults but for college students as well. An analysis of the combined impact of atherogenic risk factors indicates that they exert greater force early in life than later. Although the optimal time to begin prophylaxis is not established, there is evidence to suggest that measures instituted late in life when lesions are advanced is of only limited value. Prevention of atherosclerosis is best viewed as a family affair since the propensity to disease and contributing factors tend to be shared by family members. It is also difficult to implement effectively preventive measures which include dietary changes, weight control, exercise and restriction of cigarettes for one family member without involving the rest of the family. Optimal levels of the correctable precursors of cardiovascular disease are not established for children. However, the rise in serum lipids, blood pressure, weight and blood sugar observed in transition from childhood to adult life is not inevitable, or desirable. Paediatricians can alter the appalling cardiovascular mortality statistics by not allowing the process or the habits and conditions which promote it to reach an irreversible stage. Cardiovascular disease may well begin in childhood with “medical trivia” such as a tendency to obesity, moderate cholesterol and blood pressure elevations, lack of exercise and the cigarette habit. In some respects a heart attack at age 45 can be regarded as a failure of the paediatrician. Awaiting proof of the efficacy of the indicated prophylactic measures is not acceptable since this will be a long time in coming. We must learn how to correct risk factors effectively in childhood as soon as they appear. We must establish goals based on optimal as distinct from usual levels of risk factors. Paediatricians' resolve about prevention of atherosclerosis in childhood needs to be strengthened and we must develop a sense of urgency about this.  相似文献   
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Lipid and lipoprotein values, including fasting triglycerides and high density lipoproteins (HDL), low density lipoproteins (LDL) and total cholesterol levels, were obtained on 2,815 men and women aged 49 to 82 years chiefly between 1969 and 1971 at Framingham. In the approximately four years following the characterization of lipids, coronary heart disease developed in 79 of the 1,025 men and 63 of the 1,445 women free of coronary heart diseases. At these older ages the major potent lipid risk factor was HDL cholesterol, which had an inverse association with the incidence of coronary heart disease (p less than 0.001) in either men or women. This lipid was associated with each major manifestation of coronary heart disease. These associations were equally significant even when other lipids and other standard risk factors for coronary heart disease were taken into consideration. A weaker association with the incidence of coronary heart disease (p less than 0.05) was observed for LDL cholesterol. Triglycerides were associated with the incidence of coronary heart disease only in women and then only when the level of other lipids was not taken into account. At these ages total cholesterol was not associated with the risk of coronary heart disease.  相似文献   
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