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91.
92.
Anandamide, an endocannabinoid, prostaglandins derived from cyclooxygenase-2 and nitric oxide synthesized by nitric oxide synthase (NOS), are relevant mediators of embryo implantation. We adopted a pharmacological approach to investigate if anandamide modulated NOS activity in the receptive rat uterus and if prostaglandins mediated this effect. As we were interested in studying the changes that occur at the maternal side of the fetal-maternal interface, we worked with uteri obtained from pseudopregnant rats. Females were sacrificed on day 5 of pseudopregnancy, the day in which implantation would occur, and the uterus was obtained. Anandamide (2 ng/kg, i.p.) inhibited NOS activity (P<0.001) and increased the levels of prostaglandin E(2) (P<0.001) and prostaglandin F(2α) (P<0.01). These effects were mediated via cannabinoid receptor type 2, as the pre-treatment with SR144528 (10 mg/kg, i.p.), a selective cannabinoid receptor type 2 antagonist, completely reverted anandamide effect on NOS activity and prostaglandin levels. The pre-treatment with a non-selective cyclooxygenase inhibitor (indomethacin 2.5mg/kg, i.p.) or with selective cyclooxygenase-2 inhibitors (meloxicam 4 mg/kg, celecoxib 3mg/kg, i.p.) reverted anandamide inhibition on NOS, suggesting that prostaglandins are derived from cyclooxygenase-2 mediated anandamide effect. Thus, anandamide levels seemed to modulate NOS activity, fundamental for implantation, via cannabinoid receptor type 2 receptors, in the receptive uterus. This modulation depends on the production of cyclooxygenase-2 derivatives. These data establish cannabinoid receptors and cyclooxygenase enzymes as an interesting target for the treatment of implantation deficiencies.  相似文献   
93.

Objectives

The present study evaluated comparatively the surface roughness of four orthodontic band cements after storage in various solutions.

Material and Methods

eight standardized cylinders were made from 4 materials: zinc phosphate cement (ZP), compomer (C), resin-modified glass ionomer cement (RMGIC) and resin cement (RC). Specimens were stored for 24 h in deionized water and immersed in saline (pH 7.0) or 0.1 M lactic acid solution (pH 4.0) for 15 days. Surface roughness readings were taken with a profilometer (Surfcorder SE1200) before and after the storage period. Data were analyzed by two-way ANOVA and Tukey''s test (comparison among cements and storage solutions) or paired t-test (comparison before and after the storage period) at 5% significance level.

Results

The values for average surface roughness were statistically different (p<0.001) among cements at both baseline and after storage. The roughness values of cements in a decreasing order were ZP>RMGIC>C>R (p<0.001). After 15 days, immersion in lactic acid solution resulted in the highest surface roughness for all cements (p<0.05), except for the RC group (p>0.05). Compared to the current threshold (0.2 µm) related to biofilm accumulation, both RC and C remained below the threshold, even after acidic challenge by immersion in lactic acid solution.

Conclusions

Storage time and immersion in lactic acid solution increased the surface roughness of the majority of the tested cements. RC presented the smoothest surface and it was not influenced by storage conditions.  相似文献   
94.
Bilinguals must focus their attention to control competing languages. In bilingual aphasia, damage to the fronto-subcortical loop may lead to pathological language switching and mixing and the attrition of the more automatic language (usually L1). We present the case of JZ, a bilingual Basque-Spanish 53-year-old man who, after haematoma in the left basal ganglia, presented with executive deficits and aphasia, characterised by more impaired language processing in Basque, his L1. Assessment with the Bilingual Aphasia Test revealed impaired spontaneous and automatic speech production and speech rate in L1, as well as impaired L2-to-L1 sentence translation. Later observation led to the assessment of verbal and non-verbal executive control, which allowed JZ's impaired performance on language tasks to be related to executive dysfunction. In line with previous research, we report the significant attrition of L1 following damage to the left basal ganglia, reported for the first time in a Basque-Spanish bilingual. Implications for models of declarative and procedural memory are discussed.  相似文献   
95.
Recent trials in patients with advanced non-small-cell lung cancer (NSCLC) suggest that nonsmokers may benefit more from epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) therapy than will smokers. The aim of this systematic review was to assess smoking history as a predictive factor for treatment outcomes in patients with NSCLC. Relevant published literature was identified through systematic searches of databases (MEDLINE, EMBASE, Cochrane Library), oncology and thoracic journals, and abstracts from major oncology conferences using prespecified criteria. Articles reporting treatment outcomes (overall survival [OS], progression-free survival [PFS], and/or response rate) in smoking history subgroups from randomized controlled trials of targeted therapy and/or chemotherapy were reviewed. Data from 30 trials (32 articles, 4 abstracts) were included. Of these, 23 trials tested first-line therapy. Treatment arms included EGFR TKIs (13 trials), EGFR monoclonal antibodies (2 trials), non-EGFR targeted treatments (9 trials), chemotherapy (27 trials), and placebo or best supportive care only (3 trials). Smoking history definitions and analyses of its effect on treatment outcomes varied widely. Only 11 trials reported testing for a treatment-by-smoking history interaction. The available evidence supports but does not confirm smoking history as a predictive factor for the response to TKIs, particularly in previously treated patients. The evidence does not support smoking history as a predictor of response to non-EGFR-targeted therapies or chemotherapy. Smoking history and its effect on treatment response are inadequately reported. More rigorous collection, analysis, and reporting may clarify whether smoking history is a predictor of treatment response in advanced NSCLC.  相似文献   
96.
97.

Background

The aim of this systematic review and meta-analysis was to evaluate the efficacy of cryotherapy in reducing pain, trismus, and facial swelling in patients undergoing third-molar surgery.

Types of Studies Reviewed

The authors searched for randomized clinical trials in PubMed, Web of Science, SCOPUS, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, Google Scholar, and OpenThesis. Eligibility criteria were population: patients submitted to removal of impacted third molars; intervention and comparison: postoperative cryotherapy versus no cold therapy; and outcomes: primary outcome was postoperative pain, and secondary outcomes were facial swelling and trismus. Eligible studies must have reported at least 1 of the outcomes of interest. After extracting data and assessing quality, the authors performed the meta-analyses.

Results

The authors included 6 studies in the quantitative synthesis analysis. Differences in pain intensity were found on postoperative day 2 (weighted mean difference, ?0.72; 95% confidence interval, ?1.45 to 0.01; P = .05) and postoperative day 3 (weighted mean difference, ?0.36; 95% confidence interval, ?0.59 to ?0.13; P = .002). No evidence was found that cryotherapy was effective in reducing trismus and facial swelling. The quality of evidence was graded as low.

Conclusions and Practical Implications

Evidence suggests that cryotherapy may have a small benefit in reducing pain after third-molar surgery, but it is not effective on facial swelling and trismus. Owing to the lack of standardization of cold application, effective evidence-based treatment protocols for cryotherapy after third-molar surgery still need to be established.  相似文献   
98.
This study evaluated the root-end sealing ability of mineral trioxide aggregate (MTA Angelus), reinforced zinc oxide-eugenol cement (Super EBA), resin-modified glass ionomer (Vitremer) and zinc-free amalgam (GS-80) (control). The root canals of eighty human lower molars were accessed, cleansed, shaped and obturated. Apexes were resected and cavities were prepared. Teeth were divided into 4 groups of 40 cavities, root-end filled with the materials, and immersed in methylene blue for 72 h at 37 degrees C. Roots were then sectioned transversally at each millimeter and evaluated under magnification, observing the dye penetration in each section. Data were evaluated using Kruskal-Wallis test at a 5% level of significance, showing the differences among all materials (p < 0.001). The crescent order of microleakage was MTA < Vitremer < Super EBA < amalgam. Higher leakage levels were observed in the first millimeter sections of amalgam, Vitremer and MTA, when compared with the third millimeter section (p < 0.05).  相似文献   
99.
AIM: To analyze the results of laparoscopic colectomy in complicated diverticular disease.METHODS: This was a retrospective cohort study conducted at an academic teaching hospital. Data were collected from a database established earlier, which comprise of all patients who underwent laparoscopic colectomy for diverticular disease between 2000 and 2013. The series was divided into two groups that were compared: Patients with complicated disease(abscess, perforation, fistula, or stenosis)(G1) and patients undergoing surgery for recurrent diverticulitis(G2). Recurrent diverticulitis was defined as two or more episodes of diverticulitis regardless of patient age. Data regarding patient demographics, comorbidities, prior abdominal operations, history of acute diverticulitis, classification of acute diverticulitis at index admission and intra and postoperative variables were extracted. Univariate analysis was performed in both groups.RESULTS: Two hundred and sixty patients were included: 28%(72 patients) belonged to G1 and 72%(188 patients) to G2. The mean age was 57(27-89) years. The average number of episodes of diverticulitis before surgery was 2.1(r 0-10); 43 patients had no previous inflammatory pathology. There were significant differences between the two groups with respect to conversion rate and hospital stay(G1 18% vs G2 3.2%, P = 0.001; G1: 4.7 d vs G2 3.3 d, P < 0.001). The anastomotic dehiscence rate was 2.3%, with no statistical difference between the groups(G1 2.7% vs G2 2.1%, P = 0.5). There were no differences in demographic data(body mass index, American Society of Anesthesiology and previous abdominal surgery), operative time and intraoperative and postoperative complications between the groups. The mortality rate was 0.38%(1 patient), represented by a death secondary to septic shock in G2.CONCLUSION: The results support that the laparoscopic approach in any kind of complicated diverticular disease can be performed with low morbidity and acceptable conversion rates when compared with patients undergoing laparoscopic surgery for recurrent diverticulitis.  相似文献   
100.
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