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991.
Coronary artery disease continues to be the leading cause of death in the US. Several classes of drugs available today have shown benefit in decreasing the progression of coronary artery disease and its associated symptoms. When a patient experiences an acute coronary syndrome, beta-adrenoceptor antagonists are considered one of the cornerstones of medical therapy.Over the past 25 years, trials have demonstrated morbidity and mortality benefit when this class of drugs was given early in the post-myocardial infarction period. Subsequent substantial data have confirmed their beneficial effect on outcomes in other high-risk populations such as the elderly, those with left ventricular dysfunction, peripheral vascular disease, diabetic patients, and selected patients with reactive airway disease.Several reviews of hospital discharge data revealed that beta-adrenoceptor antagonists remain significantly underutilized in patients with acute, as well as chronic coronary artery disease. Misconceptions about the adverse effects and who would benefit probably account for physician reluctance to prescribe these medications. With rare exception, the overwhelming evidence currently supports the practice of prescribing beta-adrenoceptor antagonists to all patients immediately post-myocardial infarction and therapy to be continued indefinitely.  相似文献   
992.
993.
The objective of this prospective, randomized, double-blind study was to determine if preoperative administration of a femoral nerve block reduces the amount of morphine needed for postoperative analgesia after total knee arthroplasty (TKA). Forty-two patients undergoing TKA were randomly assigned to receive either a femoral nerve block (0.50% bupivacaine hydrochloride with epinephrine 1:200,000) or matching placebo. Results showed postoperative morphine use was significantly lower in patients who received the nerve block (25.5 vs 37.5 mg, P = .016); however, the 2 groups had similar pain scores and rehabilitative outcomes. In general, a preoperative femoral nerve block is a safe and effective adjunct for decreasing morphine use for post-TKA analgesia.  相似文献   
994.
995.
996.
Cytomegalovirus (CMV) infection accelerates transplant vascular sclerosis (TVS) and chronic rejection (CR) in both human and animal solid organ transplantation models. The host/viral mechanisms involved in this process are unclear. We examine the role of the rat CMV (RCMV)-encoded chemokine-receptor R33 in the development of TVS using a rat heart transplantation/CR model. F344 heart grafts were transplanted heterotopically into Lewis recipients. The ability of RCMV lacking the R33 gene (RCMV-Deltar33) to accelerate CR/TVS (neointimal index, NI) was compared to wild-type (WT) RCMV. Allograft recipients were infected with 1 x 10(5) pfu RCMV or RCMV-Deltar33 on postoperative day (POD) 1. Grafts from RCMV-Deltar33-infected recipients demonstrated an accelerated time to allograft CR compared to grafts from uninfected recipients (POD = 56 vs. 90), this was slower than that seen in grafts from WT-RCMV-infected recipients (POD = 45). Similarly, the degree of graft TVS formation at terminal rejection in RMCV-Deltar33 infected recipients was more severe than uninfected recipients (NI = 63 vs. 45), yet not as severe as in WT-RCMV infected recipients (NI = 83). In parallel, RCMV-Deltar33 failed to induce vascular smooth muscle cell (SMC) migration in vitro, whereas WT-RCMV induced substantial migration. The RCMV-encoded chemokine-receptor r33 is critical for RCMV-accelerated TVS/CR and vascular SMC migration.  相似文献   
997.
998.
Humoral hypercalcemia of malignancy is widely associated with tumor production of parathyroid hormone related protein (PTH-rP). This peptide functions in endocrine, autocrine and paracrine mechanisms in a manner similar to PTH; increasing renal uptake of calcium, decreasing retention of phosphorous, and stimulating adenylate cyclase and phospholipase C. Although PTH-rP production has been well documented in neoplasms of the exocrine pancreas, we present here two cases of endocrine pancreatic neoplasms elaborating PTH-rP. We then review the literature of previous cases and delve into the pathophysiology of this peptide.  相似文献   
999.
1000.
Rumination has been associated with depression and negative health effects. Yet measures of rumination appear to index multiple constructs that may be differentially related to clinical phenomena. To clarify this literature, we explored convergence and divergence among self-report measures of rumination in 349 undergraduates, 59 depressed adults, 81 healthy adults, and 15 never-depressed adults with Systemic Lupus Erythematosis (SLE). Results suggested there are separate constructs labeled rumination with different relationships to depression. Yet, aggregate measures index a central construct. Depressed individuals ruminated more, across measures, than individuals with SLE, who ruminated more than healthy individuals; this relationship was mediated by dysphoria. Thus, administering multiple rumination measures and attending to constructs assessed by rumination measures appears important in clinical studies.  相似文献   
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