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81.
The relationship between the use of cigarettes and other tobacco products and the risk of multiple myeloma was examined in a cohort of nearly 250,000 American veterans followed prospectively for 26 years. Compared with men who had never used tobacco, the risk of death from myeloma was not increased among current (relative risk [RR]=0.9, 95 percent confidence interval [CI]=0.8–1.2) or former (RR=1.0, CI=0.8–1.3) cigarette smokers, nor among users of chewing tobacco or snuff (RR=1.0, CI=0.4–2.3). Risk was only slightly and nonsignificantly increased among pipe or cigar smokers (RR=1.2, CI=0.9–1.5). There was no indication of increasing risk with amount of tobacco used or earlier age at first use. With over 90 percent power to detect a 30 percent increased risk of this tumor occuring among current cigarette smokers, this study provides the strongest evidence to date against an association of cigarette smoking with multiple myeloma.Epidemiology and Biometry Program, Division of Cancer Etiology, National Cancer Institute. Westat, Inc. Rockville, MD. National Cancer Institute, 6130 Executive Blvd, Room 418, Rockville, MD 20892, USA.  相似文献   
82.
 The effects of cocaine and quinpirole were studied in baboons to determine whether quinpirole, a relatively selective D2/D3 dopamine agonist, produced effects similar to those of cocaine on perceptual and motor processes. To measure perceptual and motor function, three baboons were trained to discriminate differences between a standard vowel and four other synthetic vowels; response accuracy as well as response latencies, or ”reaction times”, were measured following drug administrations. Cocaine reduced reaction times in two baboons, and did not affect reaction times in a third; on the other hand, quinpirole lengthened reaction times in a dose-dependent manner in all baboons. Cocaine and quinpirole also differed in the time course to produce the maximal reaction time effect following drug administration. Cocaine and quinpirole did not differ consistently in their perceptual effects, as indicated by similar changes in d′, a signal-detection index of discriminability. These distinct profiles of effects for cocaine and quinpirole suggest differing neurochemical actions for these two drugs. Received: 10 August 1996 /Final version: 16 May 1997  相似文献   
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A clinical discussion is presented of sources of sexual stress for women and how they might interfere with healthy sexual functioning. Several therapeutic techniques to reduce sexual stress are described and clinical case examples are given to clarify their use in clinical practice.  相似文献   
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We describe a case of an infant with complete congenital absence of the extraocular muscles, noted at surgery and confirmed by multiplane MR, which found no evidence of extraocular muscle tissue. This almost certainly represents an extreme form of bilateral congenital fibrosis syndrome.  相似文献   
88.
Rupture of an intra-aortic balloon counterpulsator (IABCP) demands immediate removal. We report a case of thrombus formation within a Datascope IABCP secondary to IABCP rupture, necessitating surgical exploration for removal. There is a disturbing pattern of balloon ruptures with this type of IABCP.  相似文献   
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Postoperative nausea and vomiting (PONV) is a common and potentially debilitating complication of surgery. The preoperative assessment of PONV using established risk assessment tools enables the identification of patients at risk and potentially decreases the incidence of PONV in adult surgical patients. The identification of risk factors associated with PONV and the factors that are independent predictors of PONV preoperatively can facilitate the effective prophylactic treatment and management of PONV in adult surgical patients.  相似文献   
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Acute renal insufficiency is known to occur in patients who are taking ciprofloxacin, particularly the elderly. We report two young patients with cystic fibrosis who presented with acute renal insufficiency after 2-3 weeks of oral ciprofloxacin therapy. The incidence of this adverse effect in children and young adults who have cystic fibrosis is unknown. Multiple mechanisms for ciprofloxacin-induced nephrotoxicity have been proposed.  相似文献   
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