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101.
Abstract Several previous studies have evaluated the effects of 0.12% chlorhexidine digluconate (ChD) mouthrinses on plaque and gingival inflammation. However, previously, none have been based in general dental practices. The aim of this study was to evaluate the potential to conduct controlled periodontal clinical trials in co-operation with general dental practitioners (gdps). The project took place in 5 general dental practices in the South of England. 121 healthy subjects (24 at 4 sites and 25 at the 5th). aged 18-65 years, mean 35 ± 12) years participated in a double-blind, randomised study during which they received full mouth assessments for plaque and gingival bleeding at baseline, 6 and 12 weeks. 60 subjects were randomly asigned to use the 0.12% ChD mouth wash and 6i the placebo. The assessments were carried out by 5 gpds, who had previously achieved inter-examiner κ scores of 0.78–0.85 (mean 0.81) for the plaque index (PlI), and of 0.73–0.94 (mean 0.87) for a modified gingival index (mGI), and who maintained κ scores of 0.51–0.90 for PII and of 0.73–1.00 for mGI during the 12 months required to complete the study. 98 subjects (48 ChD and 50 placebo) completed the study. Even though the baseline levels of plaque and gingivitis were low, by week 12, mean whole mouth piaque score of the ChD mouthwash users had fallen from 1.33 at baseline to 0.96 and was significantly lower (p < 0.001) than for the placebo users, 1.31 at baseline to 1.13. Whole-mouth gingival bleeding score fell from 0.56 to 0.42 in the ChD mouthwash group but was unchanged (0.54–0.55) in the placebo group. A subsidiary data analysis which considered the effects at sites indicated that within these overall differences, the ChD users experienced almost 2× the reduction from plaque score 2 at baseline at proximal molar sites over a 12-week period (50.6% ChD versus 27.6% placebo). It was concluded that 0.12% ChD mouthwash reduced plaque accumulation fay 28% and gingival inflammation by 25% over a 12–week period, that it is feasible for a group of gdps to maintain high levels of inter–examiner consistency in the use of PlI and mGI, that it is also feasible to carry out such a multicentre study in general dental practice, and that the use of mean mouth scores per subject to analyse the effects of mouthrinses may well mask variations in response throughout the mouth.  相似文献   
102.
采用抗P53单克隆抗体PAb1801和微波炉抗原修复法对53例肾癌、6例错构瘤及6例正常肾组织进行了研究。结果P53肾癌中的表达率为54.7%(29/53),在正常肾组织及肾错构瘤中无表达,P53蛋白表达与分期、分级有关(P<0.01),而与组织类型、年龄及性别无关,P53表达者预后差,说明P53可能是判断肾癌生物学行为的一个指标。  相似文献   
103.
In an open, randomized cross-over study in 124 patients, we compared the efficacy, safety and patient preference of oral and subcutaneous sum triptan in the acute treatment of migraine. Patients were treated for 3 attacks or 3 months and then crossed over. Primary clinical efficacy was defined as a reduction in headache severity on a four-point self-rating scale from severe (3) or moderate (2) to mild (1) or none (0), or mild (1) to none (0). Efficacy was evaluated 2 h after the administration of subcutaneous and 4h after the administration of oral sumatriptan. Subcutaneous sumatriptan was significantly more effective than oral sumatriptan in relieving headache (over all three attacks 78% vs 61% improvement), improving clinical disability (55% vs 41 % improvement) and relieving nausea (69% vs 53%), vomiting (72% vs 32%) and phono- or photophobia (67% vs 49%). Median time to recurrence was shorter after subcutaneous (12.5 h) than after oral sumatriptan (18 h); the number of patients experiencing a recurrence was similar Patients reported more adverse events after subcutaneous sumatriptan (1.32 per attack) than after the oral form (0.85 per attack), but all adverse events were mild to moderate in intensity and of short duration. Patient opinion was more often positive after subcutaneous sumatriptan. These results may be useful in counselling patients to choose between the available marketed formulations of sumatriptan.  相似文献   
104.
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   
105.
西安市城市居民食管癌的病因研究:烟酒因素的作用   总被引:2,自引:0,他引:2       下载免费PDF全文
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   
106.
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   
107.
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   
108.
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   
109.
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   
110.
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   
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