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81.
Eighty patients with tight and pliable mitral stenosis were randomized in a prospective trial comparing percutaneous balloon valvuloplasty and open commissurotomy. Mitral valve area increased significantly in both groups immediately after the procedures. However, a decrease in mitral valve area occurred in both groups at 6, 12 and 24 months during the follow-up. There was no death in either group. Two patients had significant mitral regurgitation after percutaneous balloon valvuloplasty. After 24 months, all patients in the commissurotomy group and 97.4% of the patients in the balloon valvuloplasty group were in New York Heart Association functional class I or II.  相似文献   
82.
The aim of this work was to develop and evaluate a 99mTc‐labeled neuropeptide Y derivative with affinity toward Y1‐receptor. The selected amino acid sequence included nine amino acids derived from the C‐terminal portion of the NPY complemented with the addition of one cysteine‐mercaptoacetic acid moiety to bind the radiometal. Labeling was achieved through the preparation of a 3 + 1 nitrido complex. Physicochemical evaluation, cell uptake, internalization and externalization studies, and competitive assays were performed. Biodistribution experiments were carried out in normal and tumor‐bearing mice. A single product with radiochemical purity >90% and high stability was obtained. In vitro analysis showed specific cellular uptake, IC50 of 73.2 nM, and a high internalization rate (80%). Biodistribution studies showed low blood and renal uptake and combined hepatobiliary and urinary elimination. Preliminary studies in mice bearing induced breast tumors rendered promising uptake values.  相似文献   
83.
It has been shown that glucocorticoids can modulate oxytocin (OT) secretion and disrupt maternal behaviour. Because the CB1 receptor (CB1R) has been implicated in some rapid glucocorticoid-induced actions, the present study aimed to evaluate the possible involvement of CB1Rs in maternal behaviour and neuronal activation during lactation. For this purpose, lactating female rats were pre-treated with dexamethasone (DEX) or saline, followed by treatment with AM251, a CB1R antagonist, or vehicle 90 min later. All of the experiments were performed 30 min after the administration of AM251 or vehicle. To evaluate maternal behaviour, the pups were returned to their home cages to the side of the cage opposite the previous nest after 12 h of separation and were filmed for the next 30 min. Aggressive behaviour was evaluated for 10 min following the placement of a male rat in the home cage. For the evaluation of behavioural performance, lactating rats were subjected to a T-maze and open-field tests. The amount of weight gained by the pups was evaluated 15 min after the onset of suckling to determine the amount of milk that they had obtained from the dam. In the central nervous system of lactating rats, c-Fos-positive nuclei were counted in the medial preoptic area, in both the ventral (v) and dorsal (d) parts of the median preoptic nucleus and in the bed nucleus of the stria terminalis (BNST). The number of neurons that were double-labelled for c-Fos/OT was counted in the medial magnocellular subdivision of the paraventricular nucleus, in the periventricular hypothalamic nucleus and in the supraoptic nucleus of the lactating rats. The results show that DEX had the following effects: (1) decreased the amount time the dam spent licking the pups, the amount of time the dam spent in an arched-nursing position and full maternal behaviour; (2) increased the latency to the first attack and decreased front attacks; (3) increased anxiety-like behaviour; and (4) decreased weight gain in the pups. In addition, DEX decreased neuronal activation in all of the investigated hypothalamic and forebrain areas. AM251 administration reversed these parameters, indicating that the behavioural effects and neuronal responses produced by DEX in lactating rats are likely to be mediated by CB1Rs.  相似文献   
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IntroductionThis study investigated the effects of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) on serum inflammatory mediators of rats with pulp exposure–induced apical periodontitis.MethodsForty male Wistar rats were divided into the following groups: control, untreated rats (C); control rats treated with ω-3 PUFAs (C-O); rats with pulp exposure–induced apical periodontitis (AP); and rats with pulp exposure–induced apical periodontitis treated with ω-3 PUFAs (AP-O). ω-3 PUFAs were administered orally once a day for 15 days before pulp exposure and continued for 30 days after pulp exposure. The rats were sacrificed, and then blood and jaw samples were collected. Blood analysis was conducted to determine the total number of leukocytes including neutrophils, monocytes, and lymphocytes. Proinflammatory cytokines tumor necrosis factor alpha, interleukin (IL) 6, and IL-17 were quantified by enzyme-linked immunosorbent assay. Histologic analysis was performed to confirm the development of apical periodontitis. The data were statistically evaluated using analysis of variance and the Tukey posttest. The significance level was set at 5%.ResultsThe development of apical periodontitis was confirmed in all infected groups. Bone destruction was larger in the AP group compared with the AP-O group (P < .05). Blood analysis showed that the AP and AP-O groups showed higher numbers of lymphocytes, leukocytes, monocytes, eosinophils, and expressions of tumor necrosis factor alpha and IL-6 compared with the C and C-O groups (P < .05). In contrast, the presence of leukocytes, lymphocytes, and the expression of IL-6 decreased in the AP-O group compared with the AP group (P < .05).Conclusionsω-3 PUFA supplementation influences the systemic effects caused by apical periodontitis, decreasing the number of leukocytes, lymphocytes, and IL-6 in rat blood.  相似文献   
87.
This study was a systematic review with meta-analysis to evaluate the influence of hyperbaric oxygen therapy (HBOT) on the survival of dental implants placed in patients who had had radiotherapy for cancer of the head and neck. A systematic literature search was conducted using the PubMed/Medline, Science Direct, Embase and the Cochrane Library, between January 1985 and July 2018. The study observed the PRISMA (Preferred Reporting Items for Systematic review and Meta-Analysis) declaration and norms, and the systematic review was duly recorded in the PROSPERO (International prospective register of systematic reviews) database. Inclusion and exclusion criteria were applied, and all articles were selected on the basis of PICO questions. The process of eligibility and quality evaluation yielded three studies for statistical analysis. Based on the survival rates, there was no evidence that the risk of an implant failing was different between the patients who received HBOT and those who did not. Moreover, the risk of an implant failing did not depend on the anatomical site. HBOT exerted no beneficial influence on the survival rates of implants placed in irradiated patients, and the risk of an implant failing did not depend on its location.  相似文献   
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Clinical Oral Investigations - This a cross-sectional study to evaluate the association between oral health findings and ventilator-associated pneumonia (VAP) among critically ill patients in...  相似文献   
89.
Clinical Oral Investigations - To assess whether salivary urea and creatinine levels accurately reflect their serum levels in blood samples of adults to detect chronic kidney disease. A systematic...  相似文献   
90.
Clinical Oral Investigations - To compare the microbial load and composition and to determine the lipopolysaccharides (LPS) and lipoteichoic acid (LTA) concentrations found in primary apical...  相似文献   
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