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71.
72.
Luiz Fernando Noira Passos da Costa Cristine da Silva Furtado Amaral Davi da Silva Barbirato Anna Thereza Thomé Leão Mariana Fampa Fogacci 《Journal of the American Dental Association (1939)》2017,148(5):308-318
Background
Through a systematic literature review, the authors evaluated the use of chlorhexidine (CHX) mouthwash as an adjunct to mechanical periodontal therapy for chronic periodontitis.Types of Studies Reviewed
The authors performed a systematic search by using PubMed (MEDLINE), Scopus, Scientific Electronic Library Online, and Cochrane Central Register of Controlled Trials. The authors selected randomized controlled clinical trials in which the investigators evaluated the probing depth (PD) and clinical attachment level (CAL) in test groups by using CHX as an adjuvant and in control groups and subject to mechanical periodontal therapy (scaling and root planing [SRP] 4-6 visits or 24 hours).Results
The literature search resulted in 8 articles, which the authors then assessed for quality. After testing for heterogeneity, the authors performed a meta-analysis only in the SRP group with 4 to 6 visits. Results were positive for both PD and CAL with use of CHX. However, the summary measure was significant (P < .05) only for PD at 40 to 60 days (0.33 millimeters; 95% confidence interval, 0.08 to 0.58 mm) and 180 days (0.24 mm; 95% confidence interval, 0.02 to 0.47 mm) of follow-up, showing positive results for the use of CHX at those times. Although those differences were statistically significant, they could be interpreted as clinically slight.Conclusions and Practical Implications
Adjunctive use of CHX mouthrinse with mechanical SRP resulted in slightly greater PD reduction than did SRP alone. Clinicians must consider the small additional gain in PD reduction, negligible effect on CAL, and potential for tooth staining when using CHX as an adjunct to SRP in treating chronic periodontitis. 相似文献73.
目的研究姜黄素对Ⅲ型慢性前列腺炎/慢性骨盆疼痛综合征(CP/CPPS)模型鼠炎性反应因子表达的影响。方法将大鼠随机分为假手术组(sham)、CP/CPPS模型组(model)、姜黄素50及100 mg治疗组(cur-50 mg,cur-100 mg)和p38抑制剂组(SB203580),连续腹腔给药12 d后,real-time PCR检测前列腺组织中TNF-α、p38、COX-2的mRNA表达;免疫组化检测TNF-α,COX-2的蛋白表达;Western blot检测p38、p-p38和NF-κB蛋白的表达。结果 CP/CPPS模型组的NF-κB、p-p38、TNF-α和COX-2蛋白,TNF-α、COX-2和p38的mRNA表达较假手术组升高(P0.01);cur-100 mg组和SB203580组可显著缓解模型组的变化(P0.01);cur-100 mg组中的COX-2蛋白和mRNA均比SB203580组明显下降(P0.05);相较模型组,姜黄素2个组、SB203580组p-p38与NF-κB的表达呈正相关(P0.01)。结论姜黄素能够降低CP/CPPS模型鼠NF-κB、TNF-α和COX-2及p-p38等炎性反应因子的表达。 相似文献
74.
Raed Al-Rajabi Sukeshi Patel Norma S. Ketchum Nicole A. Jaime Ting-Wei Lu Brad H. Pollock Devalingam Mahalingam 《Journal of gastrointestinal oncology.》2015,6(3):259-267
Background
Sorafenib is the only FDA-approved systemic therapy for advanced hepatocellular carcinoma (HCC). In clinical practice, dose reductions are often required, although there are limited efficacy data related to dose modifications. Given the prevalence of HCC in South Texas, we assessed the efficacy and safety of sorafenib therapy in relation to dose and Child Pugh (CP) score.Methods
A retrospective analysis was done of advanced HCC patients, starting sorafenib at 400 mg twice daily, or at physician discretion at 400 mg daily, with the goal of titrating to twice daily. Overall survival (OS) and progression-free survival (PFS) were assessed.Results
Among 107 patients, median OS (mOS) was 10.2 months; median PFS (mPFS) was 5.2 months. mOS for sorafenib 400 mg/day was 6.6 vs. 800 mg/day was 12.8 months [hazard ratio (HR), 0.59; P=0.04]; mPFS was 3.5 vs. 5.9 months, respectively (HR, 0.66; P=0.07). For Child Pugh A class (CP-A) patients, mOS was 15.8 months for 400 mg/day vs. 12.8 months for 800 mg/day (HR, 1.48; P=0.35); mPFS was 9.0 vs. 5.9 months, respectively (HR, 1.23; P=0.56). For Child Pugh B class (CP-B) patients, mOS was 5.0 months for 400 mg/day vs. 11.2 months for 800 mg/day (HR, 0.33; P=0.002); mPFS was 2.1 vs. 5.6 months, respectively (HR, 0.41; P=0.006). No differences in adverse events (AEs) were observed in CP-A vs. CP-B.Conclusions
Patients with CP-A or CP-B advanced HCC should be offered sorafenib at 400 mg twice daily with optimal management of AEs in order to improve survival. 相似文献75.
Objective
To investigate the effect of loading frequency on the fatigue lifetime of one standard-diameter titanium dental implant system.Methods
Thirty-six titanium dental implant specimens (Bone Level RC, Straumann) were assembled following manufacturer’s instructions and torqued into cylindrical holder blocks following the apparatus specified by the ISO 14801 test standard. Stainless steel loading hemispheres were bonded on the abutments with a moment arm of 11 mm. The holder blocks had layers of differing stiffness to simulate human jaw bone. Constant-stress fatigue lifetime testing was conducted at two frequencies (2 Hz and 15 Hz) with a stress ratio of 0.1 until fracture in deionized water at 37 °C on servo-hydraulic load frames (MTS). The fractured specimens were retrieved and examined using fractographic technique to determine the failure mode. The lifetime data were fit to a general log-linear regression model.Results
The coefficient for the load amplitude term of the regression model indicated that increasing load amplitude had a statistically significant negative effect on the fatigue lifetime. The coefficients for the cyclic frequency term and the load-frequency interaction term were not significantly different from zero, which indicated that increasing loading frequency did not have an influence on the number of cycles to failure. Fractographic analysis showed that all specimens exhibited an identical combined fracture of abutment and abutment screw adjacent to the bone level.Significance
Higher loading frequency at least up to 15 Hz may be used for future studies of some implant systems to improve the efficiency of fatigue testing. 相似文献76.
目的:探讨外周血转化生长因子(TGF-β1)浓度及高凝状态与慢性胰腺炎(CP)纤维化的关系,同时研究银杏达莫注射液对抗慢性胰腺炎纤维化的作用。方法:将50例CP患者随机分为观察组、对照组各25例。2组均给予戒烟、低脂高蛋白饮食、避免饱食等常规治疗,观察组同时予银杏达莫注射液静脉滴注,1次/d。2组连续治疗2周,观察2组治疗前后TGF-β1、凝血及血脂、血液流变学等指标的变化情况。结果:外周血TGF-β1浓度、生化指标、凝血指标、血液流变学指标2组治疗后均明显改善(P<0.05),观察组改善更明显(P<0.05)。结论:外周血TGF-β1与CP纤维化相关,银杏达莫能够抑制外周血TGF-β1表达,同时能改善CP患者血液高凝状态,有利于改善慢性胰腺炎纤维化进展。 相似文献
77.
Baśkiewicz-Hałasa M Pius E Hałasa M Dziedziejko V Grymuła K Machaliński B 《Transplant immunology》2012,26(1):34-41
Mixed chimerism has been suggested to induce tolerance to transplanted alloantigens. As the precise influence of mixed chimerism induction on the host organism has still not been fully elucidated, the aim of the present study was to explore this phenomenon in relation to the stem cell compartment.The experiment was performed on B6.SJL-PtprcaPep3b mice. Mixed chimerism induction protocols involved 3 Gy TBI (Day − 1 of the experiment), injection of 20-30 × 106 Balb C bone marrow cells (Day 0), and administration of blocking antibodies against CD40L (Day 0 and Day 4), anti-CD8 (Day − 2) with/without anti-NK1.1 (Day − 3). Selected groups of mice were also treated with cyclophosphamid (175 mg/kg) on Day 2. The presence of mixed chimerism was assessed in peripheral blood, bone marrow, and spleen, as well as in various subpopulations of leukocytes (CD4+, CD8+, CD45/B220+, Gr-1+, lin−/Sca-1+/c-kit−, lin−/Sca-1+/c-kit+, lin−/Sca-1−/c-kit+). Furthermore, the percentage of stem/progenitor cells (lin−/Sca-1+/c-kit−, lin−/Sca-1+/c-kit+, lin−/Sca-1−/c-kit+, VSEL, HSC) was analysed for the first time in bone marrow and peripheral blood of chimeric mice.The range of mixed chimerism differed significantly among various cell populations: it was lowest in CD8-positive cells and lin−/Sca-1+/c-kit− cells, and highest in granulocytes. The induction of mixed chimerism revealed a significant impact on the stem/progenitor cell frequency in recipient mice, providing potential therapeutic insights into the long-term immunologic tolerance observed in chimeric mice. Collectively, these findings contribute to further optimization of mixed chimerism induction protocols and might help in the introduction of this phenomenon into clinical practice. 相似文献
78.
目的通过生物力学研究,对比三种治疗肱骨近端骨折(Neer 3型)内固定结构的稳定性及耐久性。方法按照统一标准制作肱骨近端3部分外科颈大结节骨折模型,分别予空心钉、克氏针及三叶草钢板固定。所有标本进行循环外展实验、循环屈伸实验及压扭负载。结果加压空心钉的结构稳定性较克氏针好而次于三叶草钢板。空心钉及克氏针内固定结构稳定性与骨密度(BMD)有很大的相关性。结论加压空心钉治疗肱骨近端骨折是一种微创的内固定手术,手术时间短,能满足内固定的要求,提供术后患者进行功能锻炼的结构稳定性,是一种治疗老年肱骨近端骨折的可靠方法。 相似文献
79.
Desislava Rangelova Jens Nielsen Bertel Strandbygaard Frank Koenen Sandra Blome Åse Uttenthal 《Vaccine》2012
Marker vaccines offer the possibility to differentiate classical swine fever (CSF) infected from CSF vaccinated animals based on serology and their implementation will ensure free trade with pigs. Therefore, new generations of promising marker vaccines have been developed, among them the chimeric vaccine CP7_E2alf. However, in populations previously vaccinated with live attenuated vaccines like the C-strain, passive immunity through maternal antibodies can interfere with efficacy of CP7_E2alf vaccination. Therefore, the efficacy of CP7_E2alf was examined in piglets from sows vaccinated once intramuscularly with C-strain vaccine 4 weeks before farrowing. Thus, these piglets were vaccinated intramuscularly with CP7_E2alf at the age of 5 or 8 weeks. Subsequently, the piglets and their mock-vaccinated littermate controls were challenged 2 weeks post vaccination with highly virulent Classical swine fever virus (CSFV) strain “Koslov”. 相似文献
80.
Chu CJ Keeffe EB Han SH Perrillo RP Min AD Soldevila-Pico C Carey W Brown RS Luketic VA Terrault N Lok AS 《Gastroenterology》2003,125(2):444-451
BACKGROUND & AIMS: Hepatitis B virus (HBV) genotypes may be related to severity of liver disease and treatment response. The aims of this nationwide study were to determine the prevalence of HBV genotypes in the United States and the association between HBV genotypes and patient demographics, mode of infection, and clinical status. METHODS: A total of 694 consecutive chronic HBV-infected patients seen in 17 U.S. liver centers during a 1-year period were enrolled. Demographic, clinical, and laboratory data were collected. Sera were tested for HBV genotyping, precore, and core promoter variants by line-probe assays. RESULTS: All 7 HBV genotypes (A-G) were found, with genotypes A and C the most common. The prevalence of HBV genotypes was different in different regions of the United States. A strong correlation was found between HBV genotypes and ethnicity. HBV genotype A was prevalent among white and black patients, whereas genotypes B and C were most common among Asian patients. The predominant genotype among patients born in the United States, Europe, the Far East, and Southeast Asia were A, D, C, and B, respectively. Genotypes A and C were associated with a higher prevalence of hepatitis B e antigen. Precore variant was detected in 27% of patients and core promoter variant in 44% of patients. CONCLUSIONS: Our study suggests that the epidemiology of HBV infection in the United States may have changed over time as a result of immigration from countries with a high prevalence of HBV infection. HBV genotypes may account for the heterogeneity in disease manifestations among patients with chronic HBV infection. 相似文献