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OBJECTIVE: To provide Canadian physicians with comprehensive, evidence-based guidelines for the nonpharmacologic management and prevention of gestational hypertension and pre-existing hypertension during pregnancy. OPTIONS: Lifestyle modifications, dietary or nutrient interventions, plasma volume expansion and use of prostaglandin precursors or inhibitors. OUTCOMES: In gestational hypertension, prevention of complications and death related to either its occurrence (primary or secondary prevention) or its severity (tertiary prevention). In pre-existing hypertension, prevention of superimposed gestational hypertension and intrauterine growth retardation. EVIDENCE: Articles retrieved from the pregnancy and childbirth module of the Cochrane Database of Systematic Reviews; pertinent articles published from 1966 to 1996, retrieved through a MEDLINE search; and review of original randomized trials from 1942 to 1996. If evidence was unavailable, consensus was reached by the members of the consensus panel set up by the Canadian Hypertension Society. VALUES: High priority was given to prevention of adverse maternal and neonatal outcomes in pregnancies with established hypertension and in those at high risk of gestational hypertension through the provision of effective nonpharmacologic management. BENEFITS, HARMS AND COSTS: Reduction in rate of long-term hospital admissions among women with gestational hypertension, with establishment of safe home-care blood pressure monitoring and appropriate rest. Targeting prophylactic interventions in selected high-risk groups may avoid ineffective use in the general population. Cost was not considered. RECOMMENDATION: Nonpharmacologic management should be considered for pregnant women with a systolic blood pressure of 140-150 mm Hg or a diastolic pressure of 90-99 mm Hg, or both, measured in a clinical setting. A short-term hospital stay may be required for diagnosis and for ruling out severe gestational hypertension (preeclampsia). In the latter case, the only effective treatment is delivery. Palliative management, dependent on blood pressure, gestational age and presence of associated maternal and fetal risk factors, includes close supervision, limitation of activities and some bed rest. A normal diet without salt restriction is advised. Promising preventive interventions that may reduce the incidence of gestational hypertension, especially with proteinuria, include calcium supplementation (2 g/d), fish oil supplementation and low-dose acetylsalicylic acid therapy, particularly in women at high risk for early-onset gestational hypertension. Pre-existing hypertension should be managed the same way as before pregnancy. However, additional concerns are the effects on fetal well-being and the worsening of hypertension during the second half of pregnancy. There is, as yet, no treatment that will prevent exacerbation of the condition. VALIDATION: The guidelines share the principles in consensus reports from the US and Australia on the nonpharmacologic management of hypertension in pregnancy.  相似文献   
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The article deals with the experience in surgical treatment of 157 patients with vasorenal hypertension consequent upon unspecific aortoarteritis. On the grounds of communications in the literature and their own clinical findings, the authors analyse the character of the affection in unspecific aortoarteritis and the peculiarities of the course of vasorenal hypertension and emphasize the malignancy of its course and inefficacy of nonoperative treatment. The indications and contraindications for various reconstructive operations on the renal arteries and the dependence of the results of surgery on the duration of the disease and the term of the operative intervention are discussed in detail. The authors also describe their experience in the modern methods of kidney revascularization. With the use of radiologically guided endovascular dilatation and an nitinol endoprosthesis they not only expanded considerably the possibilities of intervention on the renal vessels but improved the results of the management of vasorenal hypertension.  相似文献   
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Effects of antidepressant medication on sexual function: a controlled study   总被引:3,自引:0,他引:3  
There has been little systematic study of the types of sexual dysfunction produced by antidepressant medication or of the frequency with which this type of adverse effect occurs. The authors report results of a double-blind study in which the effects of imipramine, phenelzine, and placebo on specific aspects of sexual function were assessed in depressed outpatients before and after 6 weeks of treatment. Both active treatments were associated with a high incidence of adverse changes in sexual function and produced significantly more adverse effects on sexual function than placebo. Orgasm and ejaculation were impaired to a greater extent than erection. Adverse sexual function changes secondary to antidepressant medication occurred frequently in both men and women, although men reported a higher incidence. Antidepressant-related sexual dysfunction may be of clinical importance for medication compliance in view of current recommendations that antidepressants be administered for longer periods as maintenance therapy or for prophylaxis.  相似文献   
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Mean subcutaneous tissue PO2 (PsqO2) measurements were obtained in dogs with an unheated electrode placed in an implanted Silastic tonometer, while PaO2 was increased in increments from 40 to 600 torr during normal, increased, and reduced blood volume. These changes reflect that the mean PsqO2 is approximately 10 torr below the PO2 of venous blood draining that tissue. Since PaO2 was already known, the oxygen content of arterial and venous blood entering and leaving this tissue could be determined by reference to blood-oxygen dissociation curves. Therefore, relative changes in blood flow could be calculated using the Fick principle. After a 20% blood loss, the PsqO2 measured during breathing of room air fell to 20% of baseline, corresponding to an 80% fall in sc blood flow; it remained low until the shed blood was returned despite compensatory changes in cardiac output. Rapid infusion of electrolyte solutions in normovolemic animals produced a temporary increase in local blood flow. Subcutaneous oximetry seems capable of quantifying peripheral perfusion and may be clinically useful.  相似文献   
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Normal and diseased isolated lungs: high-resolution CT   总被引:8,自引:0,他引:8  
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