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F Meister T J Lommel H Gerstein E E Davies 《Oral surgery, oral medicine, and oral pathology》1979,47(5):463-470
Five cases in which perforations of mandibular molars into the furca occurred during endodontic instrumentation of the canal are presented. This resulted in alveolar bone loss. All were relatively asymptomatic, which could present a problem in diagnosis of the periodontal defect. The prognosis is questionable. The only tooth retained was treated surgically by an apically positioned flap and opening of the furca area to make it accessible to cleansing. The best treatment is the avoidance of the perforation. This is accomplished by considering the configuration of the canals and the size of the reamer than can follow it. Overinstrumentation with an endodontic instrument that is too large in diameter should be avoided. 相似文献
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Autologous blood donors (ABDs) have been reported to have favorable attitudes toward returning as homologous blood donors (HBDs), but the frequency of return has not been well documented. ABDs eligible by history to be HBDs were followed at one blood center: 255 donating for elective surgery and 234 donating during pregnancy were followed for an average of 18 months and 20 months, respectively, from time of eligibility after surgery or postpartum. Male ABDs had a higher rate of return as HBDs, as 34 percent (21/62) returned to donate an average of 3 units, whereas 13 percent (56/427) of female ABDs returned as HBDs to donate an average of 2 units. Although a history of donation was associated with a higher rate of return (30%, 34/113), 11 percent (43/376) of ABDs with no history as HBDs returned to donate homologous units, despite having been recruited less frequently than prior HBDs. Overall, all male ABDs and female ABDs with an HBD history returned most frequently. The extra effort required for an autologous donor program may result in the recruitment of new donors into the HBD pool. 相似文献
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BACKGROUND: To review the presentation of Bacteroides fragilis (B fragilis) spondylodiscitis. METHODS: Two investigators independently searched the published English, Spanish and French languages literature through September 2005 using MEDLINE (1966-2005). We included all reported cases of vertebral osteomyelitis or spondylodiscitis caused by B fragilis, not related to sacral decubitus ulcers, in adults (age 16 yr and above). A third author independently reviewed all articles and extracted data for accuracy. The final pool of eligible publications included 11 articles, publication dates ranging from 1978 to 2005. Eight were written in English, two in Spanish, and one in French. RESULTS: The age of the patients in this series ranged from 17 to 74 years, with a mean age of 55 years. Male to female ratio was 6:1. Lumbar involvement was reported in nine cases, thoracic involvement in two patients and sacral involvement in one patient. B fragilis was recovered by blood culture in four patients and by tissue culture in eight patients. Metronidazole was the most common antibiotic used for treatment (eight patients), either as monotherapy or in combination with other antibiotics. CONCLUSIONS: B fragilis is a rare causative agent of spondylodiscitis, but it should be considered in patients with spondylodiscitis who have contiguous intraabdominal or pelvic infections or who had recent gastrointestinal procedures that may have led to B fragilis bacteremia. 相似文献
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Buse JB Ginsberg HN Bakris GL Clark NG Costa F Eckel R Fonseca V Gerstein HC Grundy S Nesto RW Pignone MP Plutzky J Porte D Redberg R Stitzel KF Stone NJ;American Heart Association;American Diabetes Association 《Diabetes care》2007,30(1):162-172
The American Heart Association (AHA) and the American Diabetes Association (ADA) have each published guidelines for cardiovascular disease prevention: the ADA has issued separate recommendations for each of the cardiovascular risk factors in patients with diabetes, and the AHA has shaped primary and secondary guidelines that extend to patients with diabetes. This statement will attempt to harmonize the recommendations of both organizations where possible but will recognize areas in which AHA and ADA recommendations differ. 相似文献
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Karolina Sikorska Nahid Mostafavi Montazeri André Uitterlinden Fernando Rivadeneira Paul HC Eilers Emmanuel Lesaffre 《European journal of human genetics : EJHG》2015,23(10):1384-1391
Analysis of genome-wide association studies with longitudinal data using standard procedures, such as linear mixed model (LMM) fitting, leads to discouragingly long computation times. There is a need to speed up the computations significantly. In our previous work (Sikorska et al: Fast linear mixed model computations for genome-wide association studies with longitudinal data. Stat Med 2012; 32.1: 165–180), we proposed the conditional two-step (CTS) approach as a fast method providing an approximation to the P-value for the longitudinal single-nucleotide polymorphism (SNP) effect. In the first step a reduced conditional LMM is fit, omitting all the SNP terms. In the second step, the estimated random slopes are regressed on SNPs. The CTS has been applied to the bone mineral density data from the Rotterdam Study and proved to work very well even in unbalanced situations. In another article (Sikorska et al: GWAS on your notebook: fast semi-parallel linear and logistic regression for genome-wide association studies. BMC Bioinformatics 2013; 14: 166), we suggested semi-parallel computations, greatly speeding up fitting many linear regressions. Combining CTS with fast linear regression reduces the computation time from several weeks to a few minutes on a single computer. Here, we explore further the properties of the CTS both analytically and by simulations. We investigate the performance of our proposal in comparison with a related but different approach, the two-step procedure. It is analytically shown that for the balanced case, under mild assumptions, the P-value provided by the CTS is the same as from the LMM. For unbalanced data and in realistic situations, simulations show that the CTS method does not inflate the type I error rate and implies only a minimal loss of power. 相似文献
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Neal S. Gerstein MD FASE Castigliano M. Bhamidipati DO PhD MSc Peter M. Schulman MD 《Echocardiography (Mount Kisco, N.Y.)》2018,35(6):872-875
Prosthetic valve infective endocarditis (IE) is one of the most serious postimplantation complications. Prosthetic aortic valve IE constitutes 1%–6% of all prosthetic valve IE cases. We present a dramatic echocardiographic case of prosthetic aortic valve IE leading to near‐complete valve dehiscence. Echocardiographic evidence of prosthetic aortic valve rocking motion is indicative of significant dehiscence. Aside from IE, other causes and risk factors for prosthetic aortic valve dehiscence include inflammatory and autoimmune vasculitides, concomitant ascending aorta aneurysm, and aortic root calcification. 相似文献