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101.
R. Lazzara A. A. Siddiqui P. Binon S. A. Feldman R. Weiner R. Phillips A. Gonshor 《Clinical oral implants research》1996,7(1):73-83
Osseointegrated dental implants have now become an accepted form of treatment for patients with a fully or partially missing dentition. The purpose of this study was to evaluate the performance of 3i threaded and cylindrical implants. During a 5-year period, a total of 1969 3i endosseous implants were placed at 6 centers in the United States and 2 elsewhere in the edentulous and partially edentulous jaws of 653 consecutive patients ranging in age from 18 to 82 years. Of the total number of implants placed, 1341 were commercially pure titanium threaded implants and 628 were titanium plasma-sprayed implants with a cylindrical configuration. A total of 28 patients with 110 implants were lost to follow-up. Implants in these patients were considered neither a success nor a failure. Success was predicated on the osseointegration of each and every implant followed in this analysis rather than the persistence of prosthetic function. Confirmed bone anchorage was considered essential for success. A total of 625 patients with 1871 implants remain in the study with a follow-up period ranging from 6 to 60 months. A total of 93 implants (5.0% of the total implants followed) were considered as failures. A mean implant survival rate was 95.0% for both the threaded and the cylindrical implant was calculated. The success rate of threaded implants was 97.0% in the mandible and 93.8% in the maxilla. The success rate for the 3.3mm cylindrical implants was 96.0% in the mandible and 95.5% in the maxilla, and the success rate of 4.0mm diameter cylindrical implants was 95% in the mandible and 92.0% in the maxilla. Causes of failure consisted of loss of osseointegration 2.3%crestal bone loss requiring periodontal therapy after the first year of function 1.7% and mechanical problems associated with the prosthesis 0.9%. This retrospective analysis of the 3i endosseous implant system is comparable to previous reports on other implant systems in terms of implant survival and prosthesis stability. It is demonstrated that 3i implants are predictable and can provide lasting osseointegration leading to improvement of oral function if the recommended surgical and restorative protocol is followed. 相似文献
102.
本文报道了1984年10月~1985年10月西安市城市居民138例食管癌的病例对照研究。结果表明,吸烟为食管癌发病的危险因素,ORM-H为4.12(95% CI为1.57~6.54)。OR与吸烟量、吸烟年限有显著剂量效应关系。吸烟作为食管癌的可能致病因子其潜隐期为37.19年。饮酒与食管癌的联系不显著(χ2=1.03,P﹥0.05)。作者认为吸烟单独或与其它因素共同作用下可能参与食管的癌变过程。 相似文献
103.
铸造粉尘对接尘工人肺功能影响的配对研究 总被引:3,自引:0,他引:3
按配对设计方法,排除年龄、身高等生理因素与吸烟因素的影响,分析了铸造粉尘对接尘工人肺功能的影响。结果表明:无论是铸钢或铸铁接尘工人,FVC、FEV1.0、FEF25~75、V75、V50等项指标的实测值及实测值占预计值的百分比均较对照组明显降低(P<0.05或P<0.01),肺功能的异常率则显著增高(P<0.05或P<0.01)。 相似文献
104.
房间隔入路的解剖学研究及临床应用 总被引:3,自引:0,他引:3
对33具尸体的房间隔的大小、构成及周围重要组织结构进行观察和测量。提出房间隔切开时的正确方向、安全长度及可能发生的危险。结合466例临床应用,讨论了避免切口合并症发生及发生后的正确处理方法。 相似文献
105.
为探讨孕妇乙型肝炎病毒(HBV)感染和某些因素对先天性畸形的致病作用,本文进行了96对新生儿先天畸形的配对(1:1)病例对照研究,报道先天畸形的频率和构成,单因素和多因素的条件Logistic回归分析,表明孕妇HBsAg阳性等6个因素对先天畸形呈阴性结果,而与接触农药和孕周的因素有明显联系,值得进一步探讨。 相似文献
106.
CM Reid M. Nelson P. Beckinsale P. Ryan LMH Wing LJ Beilin MA Brown GLR Jennings CI Johnston J. Marley JJ McNeil TO Morgan J. Shaw ID Steven MJ West 《Clinical and experimental pharmacology & physiology》1997,24(5):370-373
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial. 相似文献
107.
五所医院特需医疗服务状况调查 总被引:1,自引:1,他引:0
通过对上海医科大学附属华山医院、协和医院、北京同仁医院、中山医科大学附属第一医院、浙江医科大学附属第二医院开展的特需医疗服务情况的调查,论述了五所医院的具体做法,在对调查结果进行分析的基础上,就特需医疗服务的管理提出了建议。 相似文献
108.
目的 : 海岛学生饮食结构中含有碘丰富的海产品。本研究旨在了解海岛学生的碘营养状况 ,评价食盐补碘的利弊。方法 : 对定海农村 (食用碘盐 )和岱山农村 (不食用碘盐 )的学校中随机抽取的 1 2个班级 ,对碘盐组和非碘盐组的饮食碘摄入和尿碘水平等变量进行描述 ,并分别以尿碘和甲状腺肿率为应变量进行单因素和多因素回归分析。结果 : 碘盐组除碘盐外每日碘摄入量中位数为 1 84μg,而不食用加碘盐的组为 1 0 5 μg,两组饮食碘摄入有显著性差异 (u=4.71 0 ,P=0 .0 0 0 ) ,而尿碘水平在食用碘盐组和不食用碘盐组分别为 1 6 9μg/L和 1 2 9μg/L,两组间有显著性差异 (u=6 .3 0 2 ,P=0 .0 0 0 )。多因素分析中性别和是否食用碘盐对尿碘水平有显著性意义 (P<0 .0 5 ,OR值分别为 0 .76 5 ,1 .93 3 )。甲状腺肿学生和正常学生的饮食碘和尿碘无统计学差异 (P>0 .0 5 )。Poisson回归分析中性别和是否食用碘盐对甲状腺肿率有影响 (P<0 .0 5 ,OR值分别为2 .2 5 ,3 .5 2 )。结论 : 舟山海岛学生要注意补碘过程中可能出现的碘过量问题。 相似文献
109.
Wong-Ho Chow Leonard M. Schuman Joseph K. McLaughlin Erik Bjelke Gloria Gridley Sholom Wacholder Harvey T. Co Chien William J. Blot 《Cancer causes & control : CCC》1992,3(3):247-254
In 1966, a cohort of White males aged 35 or over, who were policy-holders with the Lutheran Brotherhood Insurance Society (United States), completed a mail questionnaire on tobacco use, diet, and demographic characteristics. During the 20 years of follow-up, 219 lung cancer deaths occurred. Besides the strong relationship with cigarette smoking, we observed an effect on lung cancer risk among current users of cigars or pipes who were nonsmokers of cigarettes (relative risk [RR]=3.5, 95 percent confidence interval[CI]=1.0–12.6) or who were past/occasional users of cigarettes (RR=2.7, CI=1.4–5.3). In addition, elevated risks (from 1.5 to 2.6) of lung cancer were found among craftsmen and laborers, with the highest risks among subjects who worked in the mining or manufacturing industry. No association between current (as of 1966) use of beer or hard liquor and lung cancer was observed, although past users were at elevated risk. An inverse association between lung cancer and intake of fruits was observed, and risks of lung cancer were lower among persons in the highest dietary intake quintiles of vitamins A and C. Except for oranges, however, none of the inverse associations with fruits or dietary nutrients had statistically significant trends. The findings from this cohort study add to the evidence of an adverse effect of cigar/pipe smoking and possibly protective effect of dietary factors on lung cancer risk. 相似文献
110.
Several neurons from different nuclei give rise to descending spinal tracts and project to various levels in the spinal cord of goldfish, Carassius auratus. These were visualized by retrograde transport of horseradish peroxidase (HRP) administered to the bilaterally transected spinal cord at 6 levels, corresponding to 1st, 5th, 10th, 15th, 20th and 25gh segments of the vertebral column. As many as 16 brain nuclei or neuronal aggregations and the Mauthner cells project posteriorly up to the 20th spinal segment. Restricted neurons of the dorsolateral area in the nucleus preopticus magnocellularis and those of the ventromedial nucleus of the thalamus projected up to the 20th and 25th segments respectively. In the mesencephalon, the nucleus ruber and the nucleus of the medial longitudinal fasciculus revealed retrogradely labeled somata; the former extended up to the 20th segment, while the latter projected up to the 25th segment. The remaining descending projected neurons of the brain belonged to the rhombencephalon. The nucleus of the lateral lemniscus; anterior, magnocellular, descending and posterior divisions of the octaval nucleus: raphe nucleus; Mauthner cell and the neurons located adjacent to the trigeminal tract and those in the vicinity of the secondary gustatory tract sent their processes up to 20th segmental level. However, somata of the superior, medial and inferior divisions of the reticular nucleus and restricted neurons of the facial lobe extended up to 25th segmental level. The pattern of neuronal projections into the spinal cord suggests a topographic organization. 相似文献