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Opinion statement  
–  The cardiac rhythm can be very labile in the early postoperative period, neces-sitating a high degree of vigilance.
–  Bradycardia may be due to sinus node dysfunction or varying degrees of atrio-ventricular block, both of which are usually due to surgical trauma. Temporary pacing, using implanted temporary pacing wires, should be readily available. Most often, bradycardias are transient. Patients who fail to recover an adequate sinus rhythm or atrioventricular conduction within 7 to 10 days should be treated with a pacemaker.
–  Supraventricular tachycardia, ventricular tachycardia, and junctional ectopic tachycardia are the major tachyarrhythmias of the early postoperative period. Establishing the diagnosis may require electrocardiography, atrial electrocar-diograph recordings, and the use of intravenous adenosine. The management options for patients with tachyarrhythmias include vagal maneuvers, hypo-thermia, pacing, drug therapy, catheter ablation, direct-current cardioversion, and adjuvant measures.
–  Electrolytes and acid-based balance should be checked in all patients with an arrhythmia and optimized if necessary.
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A recently described retinoblastoma cell line, FMC-RB1, showed a 16-fold N-myc oncogene amplification. The patient from whom the cell line was obtained died from an aggressive disease. It is suggested that N-myc amplification may be an adverse prognostic indicator.  相似文献   
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Picture archiving and communication systems (PACS) are expected to convert film-based radiology into a computer-based digital environment, with associated cost savings and improved physician communication. The digital workstation will be used by physicians to display these soft-copy images; however, difficult technical challenges must be met for the workstation to compete successfully with the familiar viewbox. Issues relating to image perception and the impact on physicians practice must be carefully considered. The spatial and contrast resolutions required vary according to imaging modality, type of procedure, and class of user. Rule-based software allows simple physician interaction and speeds image display. A consensus appears to be emerging concerning the requirements for the PACS workstation. Standards such as the American College of Radiology/National Electrical Manufacturers Association Digital Imaging and Communication Standard are facilitating commercial applications. Yet much careful study is needed before PACS workstations will be fully integrated into radiology departments. Abbreviations: CRT = cathode ray tube, H&D = Hurter and Drifield, PACS = picture archiving and communication system, ROC = receiver operating characteristic, S/N = signal-to-noise ratio. Partially supported by grant HL-33332 from the National Heart, Lung, and Blood institute, U.S. Public Health Service. Address reprint requests to R.L.A. Copyright © 1990 by the Radiological Society of North America. Radiology 176:303-315, 1990. Reprinted with permission.  相似文献   
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There is conflicting evidence regarding the effect of raised body mass index (BMI) on the outcome of assisted reproductive technology. In particular, there is insufficient evidence to describe the effect of BMI on live birth rates. We carried out a systematic review and meta-analysis of studies to evaluate the effect of raised BMI on treatment outcome following IVF/ICSI treatment. Subgroup analysis on overweight and obese patients was performed. Literature searches were conducted on MEDLINE, EMBASE and the Web of Science from 1966 to 2010. Thirty-three studies including 47,967 treatment cycles were included. Results indicated that women who were overweight or obese (BMI ≥ 25) had significantly lower clinical pregnancy (RR=0.90, P<0.0001) and live birth rates (RR=0.84, P=0.0002) and significantly higher miscarriage rate (RR=1.31, P < 0.0001) compared to women with a BMI < 25 following treatment. A subgroup analysis of overweight women (BMI ≥ 25-29.9) revealed lower clinical pregnancy (RR=0.91, P=0.0003) and live birth rates (RR=0.91, P=0.01) and higher miscarriage rate (RR=1.24, P < 0.00001) compared to women with normal weight (BMI < 25). In conclusion, raised BMI is associated with adverse pregnancy outcome in women undergoing IVF/ICSI treatment, including lower live birth rates. This effect is present in overweight as well as obese women.  相似文献   
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The Framingham Heart Study has enrolled 3 generations of participants, the original cohort (gen 1) enrolled in 1948, the offspring cohort (gen 2) enrolled in 1971 and the third generation enrolled in 2002. Participants have been undergoing prospective surveillance for incident stroke and dementia and embedded within this cohort is the voluntary Framingham Brain Donation Program that was begun in 1997. Participants who register to become brain donors have had one or more brain MR and cognitive test batteries administered. In addition, they undergo neurological evaluation as indicated, record review and post-mortem next-of-kin interview to determine the presence, type and extent of antemortem, clinical neurological diagnoses and to assign a retrospective clinical dementia rating (CDR) Scale score. Between 1997 and 2009 there were 1806 deaths, 186 of which were among registered brain donors and of these 139 brains could be examined. 58% were deemed cognitively normal at death. We present results for 3 projects; the first was to examine the sensitivity and specificity of our clinical diagnosis against the gold standard of pathological AD in 59 persons who underwent detailed cognitive assessment in the two years prior to death; we observed a 77.3% sensitivity (2 persons with AD were diagnosed clinically as Lewy body dementia) and a 91.9% specificity. The second examined the correlation of regional Alzheimer-type pathology to cognitive status at death among 34 persons who were over the age of 75 and without any significant vascular or alternative neurodegenerative pathology and found that neurofibrillary tangle counts distinguished between persons who were controls, had mild cognitive impairment, mild or moderate dementia; tangles in dorsolateral frontal cortex best distinguished MCI and controls. The third project examined the extent and severity of vascular pathology, again in a larger sample of varying cognitive abilities and in a subsample of persons with either amnestic or nonamnestic MCI. We observed that an aggregate ischemic injury score was significantly higher in persons with a CDR score of 0.5 than in normal controls.  相似文献   
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