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991.
Critically ill cardiac patients often undergo mechanical ventilation. The interplay between pulmonary and cardiac mechanics is complicated and in many cases may result in impaired transfer of O2 from the atmosphere to the tissues. This article addresses the principles of pulmonary and peripheral gas exchange, as well as the mechanical effects of respiration on the circulation.  相似文献   
992.
Synovial fluid phospholipase A2s and inflammation.   总被引:1,自引:1,他引:0       下载免费PDF全文
The activation of phospholipase A2 is believed to have an important role in the inflammatory process owing to its induction of eicosanoids, platelet activating factor, and other mediators. Soluble phospholipase A2 has been associated with exudates in different inflammatory conditions. In this review the general physiology and control of this enzyme and, in particular, the most recent findings on human synovial fluid phospholipase A2s are discussed.  相似文献   
993.
A variety of nutritional factors influence the bioavailability of calcium and increase a woman's risk of osteoporosis. Eight healthy women completed an 8-week metabolic study designed to investigate the effect of nonalcoholic carbonated beverage consumption on calcium metabolism. Compared with women receiving a control diet, women consuming a diet high in nonalcoholic carbonated beverages demonstrated similar mean serum levels of calcium, ionized calcium, phosphorus, alkaline phosphatase, parathyroid hormone, 1,25-dihydroxyvitamin D3, and osteocalcin. Twenty-four-hour urine volume, creatinine clearance, calcium-creatinine ratio, and phosphorus-creatinine ratio were similar during consumption of the diet high in nonalcoholic carbonated beverages and the control diet. Twenty-four-hour cyclic adenosine monophosphate-creatinine ratio was significantly lower in women consuming the diet high in nonalcoholic carbonated beverage compared with women receiving the control diet (342 +/- 27.4 nmol/mmol vs 409 +/- 22.1 nmol/mmol). Consumption of a diet high in nonalcoholic carbonated beverages on a short-term basis does not appear to affect adversely the serum or urinary markers of calcium metabolism.  相似文献   
994.
995.
996.
The acute recognition and management of CHF is challenging. A basic understanding of the determinants of cardiac performance and myocardial O2 consumption along with the pathophysiology of CHF is essential knowledge for the physician undertaking to treat this serious disorder. The basic value of the patient history and physical examination along with assessment of noninvasive tests remains unquestioned, but in addition much relevant and sophisticated information can be gained by invasive hemodynamic monitoring. The cardiopulmonary profile generated by such monitoring allows the physician to use specific hemodynamic and circulatory data for the purpose of manipulating these variables favorably for the heart and circulation. A wide array of therapeutic options is currently available, but, in general, respiratory support and pharmacotherapy are the mainstays of treatment. The traditional agents like digitalis and diuretics have assumed a lesser role during the last decade because of the availability of potent new vasodilator and inotropic agents. In addition, certain mechanical, procedural, and surgical options can be used if circumstances are urgent. In the final analysis, physicians who manage these patients must possess strong cognitive skills but also the clinical reflexes to carry them out: for every hemodynamic and circulatory action, they must be prepared to counter quickly and decisively with a clinical reaction which utilizes these principles to optimize cardiac function. It is hoped that the strategies presented in this article will allow them to perform in such a manner.  相似文献   
997.
A case is presented of severe pregnancy-induced hypertension that was complicated by oliguria and managed with the aid of a pulmonary artery catheter. This case illustrates that urinary diagnostic indices may be unreliable in predicting the etiology of oliguria. Although urinary diagnostic tests are advocated routinely as reliable in the nonobstetric literature, possible misinterpretation of these values in severe pre-eclampsia with oliguria may require confirmation with hemodynamic data obtained from a pulmonary artery catheter.  相似文献   
998.
999.
Bone and joint sepsis   总被引:1,自引:0,他引:1  
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1000.
The predictive value of female sex steroid, estrogen and progesterone, receptor (ER and PR, respectively) assays in breast, endometrial and ovarian cancer is reviewed with emphasis on comparative aspects of these malignant tumors in relation to their hormone dependency. The endocrine etiology of these three tumor types seems to be at least partly different, and so is the expression of these receptors in normal and malignant tissues of the breast, endometrium and ovary. There is a tendency for decreased receptor concentrations and disappearance of these receptors in association with advancement of these malignancies. There is also a decrease in the presence and concentrations of ER and PR in relation to loss of differentiation in breast and endometrial cancer. Receptor analyses have an established position in the selection of patients with advanced breast cancer for endocrine treatment, and they give promise of a similar application in endometrial cancer and in endometrioid cancer of the ovary. It is not clear whether the disease-free interval is related to the presence or concentrations of ER or PR as such in the tumor tissue. There is better survival in breast cancer patients with receptor-positive tumors, which might be due to a response to endocrine treatment. The same seems to be true for patients with endometrial cancer. Future progress in the application of female sex steroid receptor analyses in breast, endometrial and ovarian cancer needs additional controlled clinical trials and more highly developed receptor assays.  相似文献   
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