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51.
L S Benjamin 《Dental clinics of North America》1992,36(1):77-93; discussion 94-5
The subperiosteal implant has long been regarded as the most successful, predictable, and versatile of all implant systems. In some cases, however, anatomic morphology and surgical technique present certain limitations for the subperiosteal procedure. Through CAD/CAM multiplanar diagnostic imaging, not only have we been able to eliminate the first stage of the surgical procedure, but we have expanded the capabilities and versatility of the subperiosteal procedure. In addition, coating the subperiosteal implant frame with hydroxyapatite has allowed the achievement of bony union, thus increasing the long-range prognosis of the individual case. 相似文献
52.
53.
Shlomo Kyzer M.D. Benjamin Mitmaker M.D. Ph.D. F.R.C.S. Philip H. Gordon M.D. F.R.C.S. F.A.C.S. Hyman Schipper M.D. Ph.D. F.R.C.P. Eugenia Wang Ph.D. 《Diseases of the colon and rectum》1992,35(9):879-883
The field change is one hypothesis concerning the development of colorectal carcinoma. Removal of a carcinoma without its entire surrounding altered mucosa may result in the development of a recurrence. S44, a monoclonal antibody directed against statin, a nuclear protein expressed in nonproliferating cells in either a quiescent or senescent state, was used to determine the rate of cell growth in colorectal mucosa at different distances from carcinomas. The specimens of 18 patients undergoing resection of a colorectal carcinoma were immediately opened after operation, and strips of mucosa were taken at distances of 1 cm, 5 cm, and 10 cm from the carcinoma. For each location, 10 longitudinally oriented crypts were evaluated for statin-positive cells identified by the presence of a dark brown peroxidase-conjugated antibody reaction product. The average percentage of statin-positive cells per crypt was significantly lower at a 1-cm distance from the carcinoma compared with the mucosa located 5 and 10 cm from the carcinoma (20.89±4.33 at 1 cm, 32.41±5.27 at 5 cm, and 34.23±6.45 at 10 cm). None of the calculated parameters showed any significant difference between the 5-cm and 10-cm locations. The fact that the proliferation rate of the mucosal cells returns to the normal level at 5 cm from the margin of the carcinoma suggests that cells located within this distance still retain proliferative potential even though they are morphologically indistinguishable from their normal counterparts. We conclude that failure to remove this transitional, potentially proliferative mucosa may result in subsequent development of anastomotic or perianastomotic recurrences.This study was conducted with support from the Sir Mortimer B. Davis-Jewish General Hospital Foundation and the American Physician Fellowship and with grants to Eugenia Wang from the Medical Research Council of Canada and from the National Institute on Aging of the National Institutes of Health of the U.S.A. 相似文献
54.
D E Fleischer F al-Kawas S Benjamin J H Lewis J Kidwell 《Gastrointestinal endoscopy》1992,38(4):411-414
In 1989, the American Society for Gastrointestinal Endoscopy released a quality assurance monograph in which a procedure review process was outlined. The major elements of the program for quality assurance in gastrointestinal endoscopy included: (1) procedure reports, (2) an endoscopic unit record, and (3) a procedure review. This study was designed to use the procedure review process to determine the incidence of complications, to identify quality assurance issues, and to determine whether audits and/or studies would result from this process. To make a meaningful interpretation as to what constitutes an important complication, a classification to define potential problems was established. Using this classification, a complication was identified in 64 of 3287 procedures (1.9%). These complications were discussed in a monthly morbidity and mortality conference. Additionally, 21 quality assurance issues were identified that led to four studies addressing these quality assurance issues. 相似文献
55.
Benjamin Volovitz Jacob Amir Hagit Malik Maya Lerman Itzhak Varsano 《The Journal of asthma》1994,31(1):27-34
Administration of theophylline to asthmatic children is frequently associated with an adverse influence on their behavior. The efficacy and behavioral effects of the administration of high-dose theophylline (T) and ketotifen (K) in various combinations were evaluated prospectively in a double-blind, placebo controlled study in 55 children with moderately severe perennial asthma. During a baseline period of 2 weeks, theophylline (serum level of 10-20 μg/ml) was administered to all the children. After this period the patients were randomly allocated into four comparable groups. The children were treated during a 12-week period with: T + K-Placebo (T group); T + K (T + K group); half-dose T + K (T/ 2 + K group); or placebo of both T and K (P group). During the 12-week treatment period, as compared to the baseline period, only the three groups of children who received active therapy (T + P, T + K, T/2 + K) showed a similar reduction in the number of days with asthmatic symptomatology, improvement of the total asthmatic symptoms score, and increased PEFR. The behavioral activity of the children (assessed by the Conner's rating scale) improved significantly only in the groups receiving placebo or T/2 + K. The results of this study suggest that a combination therapy of half the recommended therapeutic dose of theophylline with ketotifen can be clinically as effective as therapy with a full dose of theophylline, but with significantly less adverse behavioral effects. 相似文献
56.
What is the prognostic value of myocardial perfusion imaging using rubidium-82 positron emission tomography? 总被引:5,自引:0,他引:5
Keiichiro Yoshinaga Benjamin J W Chow Kathryn Williams Li Chen Robert A deKemp Linda Garrard Alexander Lok-Tin Szeto May Aung Ross A Davies Terrence D Ruddy Rob S B Beanlands 《Journal of the American College of Cardiology》2006,48(5):1029-1039
OBJECTIVES: The objective was to determine the prognostic value of rubidium-82 (82Rb) positron emission tomography (PET) myocardial perfusion imaging (MPI). BACKGROUND: 82Rb PET MPI accurately diagnoses coronary artery disease (CAD). However, there are limited data evaluating its prognostic value. METHODS: Follow-up (3.1 +/- 0.9 years) was obtained in 367 patients who underwent dipyridamole 82Rb PET MPI. Patients were divided into groups based on their summed stress score (SSS): group I, normal (<4); group II, mild (4 to 7); and group III, moderate (8 to 11) to severe (> or =12). RESULTS: There were significant differences among patients in the 3 SSS groups for hard events (cardiac death and myocardial infarction [MI]) (p < 0.001) and total cardiac events (hard events, revascularization and hospitalization) (p < 0.001). The annual hard events rates were 0.4%, 2.3%, and 7.0% in the normal, mild, and moderate-severe groups, respectively. In adjusted survival models, 82Rb PET SSS was the strongest predictor of total cardiac events and a significant predictor of hard events. Among patients referred for PET after 99mTc single-photon emission computed tomography, the annual total event rate was higher with abnormal versus normal SSS on PET (15.2% vs. 1.3%, p < 0.001). In patients with obesity, the annual total event rate was 11.1% with an abnormal scan and 1.5% with a normal scan (p < 0.001). CONCLUSIONS: This study shows that 82Rb PET MPI has significant prognostic value for predicting cardiac events, including death and MI. It also seems to have prognostic value in patients whose diagnosis remains uncertain after single-photon emission computed tomography MPI and in obese patients. The prognostic value of PET MPI may improve the management of cardiac patients. 相似文献
57.
Michael J Huerkamp Kimberly A Benjamin Sonji K Webb Jennifer K Pullium 《Contemporary topics in laboratory animal science》2004,43(2):35-36
The pinworm Syphacia muris was eradicated from rats after treatment with fenbendazole-medicated chow (150 ppm) and without environmental decontamination for > 54 months. However, this regimen was successful only when the treatment was delivered and efficacy monitoring was done by personnel of the institutional animal resources program. The same pinworm elimination program failed 7 to 24 months after the cessation of treatment in a satellite colony in which animal care, including provision of medicated diet and sample collection for efficacy monitoring, was provided by research personnel. A failure to uniformly deliver adequate therapeutic doses or reinoculation of rats with pinworm eggs from the contaminated environment could not be excluded as causes of the failure. However, there were risk factors, and animal care practices unique to the satellite colony that may have facilitated the re-emergence of pinworms. These risk factors included hand-washing of cages, storage of contact bedding in areas that were not vermin-proof, and animal care provided by personnel having contact with rodents of pet-store origin. 相似文献
58.
The Multiphasic Environmental Assessment Procedure (MEAP; Moos and Lemke, 1984) was used to assess three long-stay settings within a geriatric hospital, one of which is a non-nursing unit committed to the philosophy of residents viewing the setting as their own home. Findings suggest positive outcomes for residents on the nonnursing unit, and support the view that types of care fostering independence and personal responsibility of elderly residents in their setting may be associated with increased mental functioning and activity. The lack of trained nursing staff had no detrimental effect on any measure of resident life, and some specific caring practices on the unit may be interpreted as having a positive outcome for residents. 相似文献
59.
Flexible Sigmoidoscopy Screening in an Industrial Setting 总被引:1,自引:0,他引:1
Benjamin Krevsky M.D. M.P.H. F.A.C.G. Tomasz Niewiarowski M.D. Rita League R.N. Harold Herman M.D. Lisa Matz Robert S. Fisher M.D. F.A.C.G. 《The American journal of gastroenterology》1992,87(12):1759-1762
Little is known about the yield of colorectal cancer screening programs in an industrial setting. We therefore established a flexible sigmoidoscopy screening program at a chemical manufacturing plant and offered testing to all employees over the age of 40. After a Fleet enema preparation had been administered, a digital rectal examination and sigmoidoscopy were performed on each volunteer worker in the medical office of the plant. The plant had an average census of about 650 workers; 202 were screened during a 2-yr period. The mean (+/- SEM) age of participants was 52 +/- 0.4. Sixty-four employees had polyps (31.7%); data on follow-up colonoscopy were available in 69%. Colonoscopy revealed adenomatous polyps in 23 workers (53.5%), hyperplastic polyps in 10 (23%), and no evidence of neoplasia in 10 (23%). Seven workers did not arrange for follow-up colonoscopy and 12 individuals could not be contacted. No cancers were detected. In the 40- to 50-yr age group, polyps were detected in 19.5% of employees (25% adenomatous). Incidental findings were common, and included prostatic nodules, hemorrhoids, diverticulosis, and proctitis, among others. We conclude that screening sigmoidoscopy can be conveniently and economically performed at the workplace, with a high yield and good worker acceptance. The high yield suggests a possible association between polyp formation and work in a chemical plant. The finding of adenomatous polyps in the younger patients suggests that the threshold for flexible sigmoidoscopy at age 50 needs to be reassessed. 相似文献
60.
Chemotherapy of bilateral acoustic neuromas 总被引:2,自引:0,他引:2
In patients with bilateral acoustic neuromas, it is not unusual for the tumors to be of unequal size. At the time of the first examination, the smaller tumor may have already destroyed the hearing, while the ear with residual hearing may harbor a large acoustic neuroma. The remaining hearing is then at great risk if surgical removal of the tumor is attempted. Chemotherapy of bilateral acoustic neuromas is here presented as a possible alternative to surgery in those patients whose prognosis for conservation of hearing is poor. 相似文献