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31.
Difficult airway management is a dilemma for any anesthesiologist. Although practice guidelines and algorithms may help in such situations, the anesthesiologist's judgment and vigilance remain the primary means to save lives. In the following case, we encountered an acutely enlarging thyroid mass that was compromising the airway. This huge neck mass precluded tracheostomy under local anesthesia, and the patient could breathe only in the sitting position. Therefore, there were few safe strategies for airway management for general anesthesia. We reiterate the role of awake fiberoptic intubation in such circumstances.  相似文献   
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33.

Purpose

To assess the impact of perioperative blood transfusion on overall and disease-free survival in patients undergoing curative resection for cholangiocarcinoma.

Methods

In a single-center study, 128 patients undergoing curative resection for cholangiocarcinoma between 2001 and 2010 were assessed. The median follow-up period was 19 months. Transfused and nontransfused patients were compared by Cox regression and propensity score analyses.

Results

Overall, 38 patients (29.7 %) received blood transfusions. The patient characteristics were highly biased with respect to receiving transfusions (propensity score 0.69 ± 0.22 vs. 0.11 ± 0.16, p < 0.001). In the unadjusted analysis, blood transfusion was associated with a 105 % increased risk of mortality [hazard ratio (HR) 2.05, 95 % CI 1.19–3.51, p = 0.010]. In the multivariate (HR 1.14, 95 % CI 0.52–2.48, p = 0.745) and the propensity score-adjusted Cox regression (HR 1.02, 95 % CI 0.39–2.62, p = 0.974), blood transfusion had no influence on overall survival. Similarly, in the propensity score-adjusted Cox regression (HR 0.62, 95 % CI 0.24–1.58, p = 0.295), no relevant effect of blood transfusion on disease-free survival was observed.

Conclusions

To our knowledge, this is the first propensity score-based analysis providing compelling evidence that the worse oncological outcome after curative resection for advanced cholangiocarcinoma in patients receiving perioperative blood transfusions is caused by the clinical circumstances requiring the transfusions, not by the blood transfusions themselves.  相似文献   
34.
PURPOSE: Transesophageal echocardiography has emerged as an accepted approach before D.C. cardioversion for atrial fibrillation. The frequency of atrial thrombi detected on transesophageal echocardiography has varied from 7% to 23%. Many patients undergoing transesophageal echocardiography have had a previous transthoracic echocardiogram. Though transthoracic echocardiography has a low yield for the detection of intracardiac thrombi, it is highly accurate in diagnosing a structurally abnormal heart. The purpose of this study was to assess the frequency of thrombi detected by transesophageal echocardiography in patients with an entirely normal transthoracic echocardiogram and hence the advocacy of a selective approach in performing transesophageal echocardiography in patients undergoing D.C. cardioversion for atrial fibrillation. METHODS: 112 consecutive patients with atrial fibrillation who had undergone transesophageal echocardiography before D.C. cardioversion were evaluated. They all had a transthoracic echocardiogram within the 2 months preceding their transesophageal echocardiogram. Based on their transthoracic echocardiographic study, they were divided into two groups: Group 1 consisted of patients with a normal transthoracic echocardiogram and Group 2, those with an abnormal study. RESULTS: Thrombi or spontaneous echo contrast were found in 14 of 112 patients (16%). All however were detected in Group 2 patients. There was no patient with a normal transthoracic echocardiogram who had thrombus on his/her transesophageal echocardiogram. CONCLUSIONS: Our results suggest that a selective approach may be exercised in the use of transesophageal echocardiography prior to D.C. cardioversion for atrial fibrillation. Patients with an entirely "normal" transthoracic echocardiogram may proceed directly to cardioversion without a precardioversion transesophageal echocardiogram.  相似文献   
35.
Spontaneous antitumor T cell responses in cancer patients are strongly controlled by Tregs, and increased numbers of tumor-infiltrating Tregs correlate with reduced survival. However, the tumor antigens recognized by Tregs in cancer patients and the impact of these cells on tumor-specific T cell responses have not been systematically characterized. Here we used a broad panel of long synthetic peptides of defined tumor antigens and normal tissue antigens to exploit a newly developed method to identify and compare ex vivo the antigen specificities of Tregs with those of effector/memory T cells in peripheral blood of colorectal cancer patients and healthy subjects. Tregs in tumor patients were highly specific for a distinct set of only a few tumor antigens, suggesting that Tregs exert T cell suppression in an antigen-selective manner. Tumor-specific effector T cells were detectable in the majority of colorectal cancer patients but not in healthy individuals. We detected differences in the repertoires of antigens recognized by Tregs and effector/memory T cells in the majority of colorectal cancer patients. In addition, only effector/memory T cell responses against antigens recognized by Tregs strongly increased after Treg depletion. The selection of antigens according to preexisting T cell responses may improve the efficacy of future immunotherapies for cancer and autoimmune disease.  相似文献   
36.
Cancer gender disparities have been observed for a variety of human malignancies. Thyroid cancer is one such example where there is a dramatic difference in the incidence, aggressiveness, and death rate by gender. The molecular basis for gender disparity is poorly understood. To address this, we performed genome-wide gene expression profiling in matched papillary thyroid cancer (PTC) samples and identified nine candidate genes differentially expressed by gender. One of these genes was CDC23 that was upregulated in PTC in men compared with women. Because the function and expression of CDC23 is unknown in eukaryotic cells, we further characterized the expression of CDC23 in normal, hyperplastic, and PTC tissue samples. We found CDC23 was overexpressed in PTC and absent in normal and hyperplastic thyroid tissue. In thyroid cancer cells, functional knockdown of CDC23 resulted in an increase in the number of cells in both the S and G(2)M phases of the cell cycle, and an inhibition of cellular proliferation, tumor spheroid formation, and anchorage-independent growth. Cellular arrest in both S and G(2)M phases was associated with significant cyclin B1 and securin protein accumulation after CDC23 knockdown. Moreover, the effect of CDC23 on cellular proliferation and cell cycle progression was reversed on triple knockdown studies of CDC23, cyclin B1, and securin. Our data taken together suggests CDC23 has important biologic effects on cell proliferation and cell cycle progression. The effect of CDC23 on cellular proliferation and cell cycle progression is mediated, at least in part, by cyclin B1 and securin protein levels. Therefore, we propose that CDC23 is a critical regulator of cell cycle and cell growth, and may be involved in thyroid cancer initiation and progression, and may explain the different tumor biology observed by gender.  相似文献   
37.
AIMS: Uremia is a prediabetic state, but abnormal glucose metabolism and relative risk factors in non-diabetic chronic kidney disease (CKD) patients are not studied extensively. This study aimed to evaluate prediabetes and contributing factors in patients with CKD. METHODS: We studied the frequency of prediabetes (defined as fasting plasma glucose 100-125 mg/dl and 2-h plasma glucose 140-199 mg/dl) and contributing risk factors in 91 (34 women and 57 men) non-diabetic CKD (GFR < 60) patients who were referred to Sina Hospital between November 2010 and November 2011. Impaired fasting glucose and impaired glucose tolerance were regarded as prediabetic state. RESULTS: Thirty-eight patients (41.8%), 28 male and 10 female, with mean age of 57.4 ± 17.1 yr, had prediabetes. Among these, 18.7% had impaired fasting glucose, 7.7% impaired glucose tolerance, and 15.4% combined impaired fasting glucose and impaired glucose tolerance. CKD patients with impaired glucose tolerance had more frequently hypertriglyceridemia (85.7% vs. 42.0%, p = 0.001), hypertension (66.6% vs. 31.4%, p = 0.004), and metabolic syndrome according to National Cholesterol Education Program Adult Treatment Panel III (52.3% vs. 25.7%, p = 0.02). Also, mean systolic blood pressure (134.2 ± 13.9 vs. 124.5 ± 20.0, p = 0.004) was higher in CKD patients with impaired glucose tolerance compared to CKD patients with normal glucose. CONCLUSIONS: Prediabetes is a frequent condition in CKD patients. Also, hypertriglyceridemia and hypertension are more prevalent in prediabetic CKD patients than in non-diabetic CKD patients.  相似文献   
38.
Helicobacter DNA has been detected in the liver specimens of patients with various hepato-biliary diseases. The aim of this study was to investigate the presence of H. pylori DNA in the liver tissue of Iranian patients with chronic liver diseases (CLD). Genomic DNA was extracted from the paraffin sections of 46 liver biopsies of patients with CLD and 13 from patients with metastatic adenocarcinoma as a control group. Polymerase chain reaction (PCR) analysis was carried out using primers for H. pylori 16S rRNA and cagA genes. On analysis, 17 of the 46 patient samples were positive in H. pylori 16S rRNA PCR and 2 of the 13 were positive from the control group. None of the samples were positive for the cagA gene. This study showed the greater presence of H. pylori-like DNA in the liver samples from patients with CLD than in controls.  相似文献   
39.

Statement of problem

The masking ability of zirconia ceramics as copings is unclear.

Purpose

The purpose of this in vitro study was to evaluate the effect of coping thickness and background type on the masking ability of a zirconia ceramic and to determine zirconia coping thickness cut offs for masking the backgrounds investigated.

Material and methods

Thirty zirconia disks in 3 thickness groups of 0.4, 0.6, and 0.8 mm were placed on 9 backgrounds to measure CIELab color attributes using a spectrophotometer. The backgrounds included A1, A2, and A3.5 shade composite resin, A3 shade zirconia, nickel-chromium alloy, nonprecious gold-colored alloy, amalgam, black, and white. ΔE values were measured to determine color differences between the specimens on the A2 shade composite resin background and the same specimens on the other backgrounds. The color change (ΔE) values were compared with threshold values for acceptability (ΔE=5.5) and perceptibility (ΔE=2.6). Repeated measures ANOVA, the Bonferroni test, and 1-sample t tests were used to analyze data (α=.05).

Results

Mean ΔE values ranged between 1.44 and 7.88. The zirconia coping thickness, the background type, and their interaction affected the CIELab and ΔE values (P<.001).

Conclusions

To achieve ideal masking, the minimum thickness of a zirconia coping should be 0.4 mm for A1 and A3.5 shade composite resin, A3 shade zirconia, and nonprecious gold-colored alloy, 0.6 mm for amalgam, and 0.8 mm for nickel-chromium alloy.  相似文献   
40.
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