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1.
The majority of vascular access thrombosis episodes in hemodialysis patients are due to anatomic abnormalities. Thrombophilias are inherited, acquired or mixed disorders which also predispose to venous thromboembolism. They include protein C, protein S and antithrombin deficiencies, as well as gene mutations for prothrombin and factor V Leiden. The most important of the mixed cases is hyperhomocysteinemia, which includes both a genetic and an acquired substrate. We report two patients undergoing hemodialysis who suffered from multiple thrombotic events, the first due to factor V Leiden heterozygosity and the second because of hyperhomocysteinemia due to homozygosity for MTHFR C677T mutation. As no site for vascular access was left, transfer to peritoneal dialysis for both patients improved solute clearance and quality of life with no additional thrombotic events noted.  相似文献   
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The rat model is widely used in periodontal research and the quality of histological sections is essential. The purpose of this study was to evaluate the histological characteristics of periodontal tissues in Wistar rat maxillae, with different times of fixation and decalcified by nitric acid or formic acid (Anna Morse Solution). Fifteen rats were used. Fixation was performed for 24, 48 and 72 hours. The maxillae were hemi-sectioned and each part was decalcified either in nitric acid for 7 days or in Anna Morse solution for 35 days. Two trained and blinded examiners performed the evaluation. Fourty eight hours of fixation and decalcification with Anna Morse solution showed more clear characteristics of the epithelium-connective tissue interface and of the periodontal structures. Mean measurements between the cementum-enamel junction and the bone crest varied in the different experimental times from 176.5 (+/- 60.45) to 210.94 (+/- 39.33) pixels on the buccal aspect, and from 199.69 (+/- 38.33) to 298.55 (+/-70.81) pixels on the palatal aspect, with no statistically significant differences (ANOVA, p > 0.05). In the same fixation period, decalcification with nitric acid or Anna Morse solution did not display any statistically significant differences. It may be concluded that for a qualitative histological analysis, fixation should preferably be for 48 hours and the demineralization should be made by Anna Morse solution. For a histomorphometric analysis, the decalcification solution does not interfere in the results.  相似文献   
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Background

Recent studies have indicated that preoperative biliary drainage (PBD) should not be routinely performed in patients suffering from obstructive jaundice before surgery. The severity of jaundice that mandates PBD has yet to be defined. Our aim was to investigate whether PBD is truly justified in severely jaundiced patients before pancreaticoduodenectomy. The parameters evaluated were overall morbidity, length of hospital stay, and total in-hospital mortality.

Methods

From January 2000 to December 2012, a total of 240 patients underwent pancreaticoduodenectomy for periampullary tumors. Group A comprised 76 patients with preoperative serum bilirubin ≥15 mg/dl who did not undergo PBD before surgery. Group B comprised another 76 patients, matched for age and tumor localization (papillary vs. pancreatic head) who underwent PBD 2–4 weeks before pancreaticoduodenectomy and were identified from the same database.

Results

Less operative time was required in the ‘no PBD’ group compared with the ‘PBD’ group (210 vs. 240 min). Total intraoperative blood loss and blood transfusions were also significantly less in the ‘no PBD’ group. There was no difference detected in the rate of pancreatic fistula or biliary fistula formation. Group A patients demonstrated significantly lower morbidity than group B (24 vs. 36 %, respectively) and therefore required briefer hospitalization (11 vs. 16 days). Mild infectious complications appear to be the main factor that enhanced morbidity in the PBD group. However, total in-hospital mortality was not significantly different between the two groups.

Conclusions

Even severe jaundice should not be considered as an indication for PBD before pancreaticoduodenectomy, as PBD increases infections and postoperative morbidity, therefore delaying definite treatment.  相似文献   
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The effects of topical copaiba oil extract and topical corticosteroid were assessed on oral wound healing in an in vivo model using 96 male Wistar rats. Traumatic ulcers were caused in the dorsum of the tongue using a 3‐mm punch tool. The animals were divided into: Control; Corticosteroid; Placebo and Copaiba oil Group. The animals received two daily applications of the products. The control group received only daily handling. Six rats in each group were euthanized at days 3, 5, 10 and 14. The animals were monitored daily to determine wound status. The weigh was assessed at day 0 and euthanasia day. The percentage of repair was calculated, and histopathological aspects were analyzed. The Kruskal–Wallis test was used to compare the results between groups and times of evaluation. Closing time was assessed through the log‐rank test. The corticosteroid group lost more weight at days 10 and 14 than the control group (p < 0.05). Moreover, the healing time of corticosteroid group was longer than the control group (p = 0.007). No differences were observed between the copaiba oil group and the control group. We concluded that topical copaiba oil, in spite of being safe, did not accelerate the process of oral wound healing. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
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Cell invasion and metastasis are involved in clinical failures in cancer treatment, and both events require the acquisition of a migratory behavior by tumor cells. Curcumin is a promising natural product with anti‐proliferative activity, but its effects on cell migration are still unclear. We evaluated the effects of curcumin on the proliferation, apoptosis, migration, and cell–cell adhesion of keratinocyte, oral squamous cell carcinoma (OSCC), and fibroblast cell lines, as well as in a xenograft model of OSCC. Curcumin (2 μM) decreased cell proliferation in cell lines with mesenchymal characteristics, while cell death was detected only at 50 μM. We observed that highly migratory cells showed a decrease on migration speed and directionality when treated with 2 or 5 μM of curcumin (50% and 40%, respectively, p < 0.05). Using spheroids, we observed that curcumin dose dependently decreased cell–cell adhesion, especially on tumor‐derived spheroids. Also, in a xenograft model with patient‐derived OSCC cells, the administration of curcumin decreased tumor growth and aggressiveness when compared with untreated tumors, indicating the potential antitumor effect in oral cancer. These results suggest that lower doses of curcumin can influence several steps involved in tumorigenesis, including migration properties, suggesting a possible use in cancer therapy. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
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European Archives of Psychiatry and Clinical Neuroscience - Episodic memory ability relies on hippocampal-prefrontal connectivity. However, few studies have examined relationships between memory...  相似文献   
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ObjectivesCentral poststroke pain (CPSP), a neuropathic pain condition, is difficult to treat. Repetitive transcranial magnetic stimulation (rTMS) targeted to the primary motor cortex (M1) can alleviate the condition, but not all patients respond. We aimed to assess a promising alternative rTMS target, the secondary somatosensory cortex (S2), for CPSP treatment.Materials and MethodsThis prospective, randomized, double-blind, sham-controlled three-arm crossover trial assessed navigated rTMS (nrTMS) targeted to M1 and S2 (10 sessions, 5050 pulses per session at 10 Hz). Participants were evaluated for pain, depression, anxiety, health-related quality of life, upper limb function, and three plasticity-related gene polymorphisms including Dopamine D2 Receptor (DRD2). We monitored pain intensity and interference before and during stimulations and at one month. A conditioned pain modulation test was performed using the cold pressor test. This assessed the efficacy of the descending inhibitory system, which may transmit TMS effects in pain control.ResultsWe prescreened 73 patients, screened 29, and included 21, of whom 17 completed the trial. NrTMS targeted to S2 resulted in long-term (from baseline to one-month follow-up) pain intensity reduction of ≥30% in 18% (3/17) of participants. All stimulations showed a short-term effect on pain (17–20% pain relief), with no difference between M1, S2, or sham stimulations, indicating a strong placebo effect. Only nrTMS targeted to S2 resulted in a significant long-term pain intensity reduction (15% pain relief). The cold pressor test reduced CPSP pain intensity significantly (p = 0.001), indicating functioning descending inhibitory controls. The homozygous DRD2 T/T genotype is associated with the M1 stimulation response.ConclusionsS2 is a promising nrTMS target in the treatment of CPSP. The DRD2 T/T genotype might be a biomarker for M1 nrTMS response, but this needs confirmation from a larger study.  相似文献   
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BACKGROUND: The aim of this study was to determine the value of small-bowel preparation for patients undergoing capsule endoscopy. METHODS: The study design was prospective, randomized, and controlled. Eighty patients referred for capsule endoscopy were randomized into two equal groups. Patients in Group A (mean age 54.40 [15.65] years) ingested 2 L of a polyethylene glycol/electrolyte solution 16 hours before the test, whereas patients in Group B (mean age 59.85 [14.58] years) prepared for the procedure by taking only clear liquids during the prior day. The primary outcome evaluated was the effect of bowel preparation on the quality of capsule images, as assessed with an objective scoring system in which cleansing was graded as "adequate" or "inadequate" by blinded examiners. A secondary outcome was the effect of bowel preparation on diagnostic yield. For this purpose, the results of capsule endoscopy were classified as positive findings, findings of uncertain significance, and no findings. RESULTS: Cleansing of the small intestine was considered "adequate" in 36 patients in Group A (90%) vs. 24 patients of Group B (60%) (p = 0.004). A diagnosis was established in 26 patients in Group A (65%) compared with 12 patients in Group B (30%) (p = 0.003). CONCLUSIONS: Bowel preparation before capsule endoscopy improves visualization of the small intestine, which may lead to an improvement in diagnostic yield.  相似文献   
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