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31.

Purpose  

The transduction mechanism of the inner ear and the transmission of nerve impulses along the auditory way are highly dependent upon the cochlear oxygen supply. Several studies have considered the possibility that obstructive sleep apnea–hypopneas during sleep can interfere with these processes, and the results are not uniform. The aim of the study is to evaluate the auditory function in adult patients affected by severe obstructive sleep apnea syndrome (OSAS).  相似文献   
32.
AIM: To compare the site, age and gender of cases of colorectal cancer (CRC) and polyps in a single referral center in Rome, Italy, during two periods.METHODS: CRC data were collected from surgery/pathology registers, and polyp data from colonoscopy reports. Patients who met the criteria for familial adenomatous polyposis, hereditary non-polyposis colorectal cancer syndrome or inflammatory bowel disease were excluded from the study. Overlap of patients between the two groups (cancers and polyps) was carefully avoided. The χ2 statistical test and a regression analysis were performed.RESULTS: Data from a total of 768 patients (352 and 416 patients, respectively, in periods A and B) who underwent surgery for cancer were collected. During the same time periods, a total of 1693 polyps were analyzed from 978 patients with complete colonoscopies (428 polyps from 273 patients during period A and 1265 polyps from 705 patients during period B). A proximal shift in cancer occurred during the latter years for both sexes, but particularly in males. Proximal cancer increased > 3-fold in period B compared to period A in males [odds ratio (OR) 3.31, 95%CI: 2.00-5.47; P < 0.0001). A similar proximal shift was observed for polyps, particularly in males (OR 1.87, 95%CI: 1.23-2.87; P < 0.0038), but also in females (OR 1.62, 95%CI: 0.96-2.73; P < 0.07).CONCLUSION: The prevalence of proximal proliferative colonic lesions seems to have increased over the last decade, particularly in males.  相似文献   
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Agaugué S  Marcenaro E  Ferranti B  Moretta L  Moretta A 《Blood》2008,112(5):1776-1783
Dendritic cells (DCs) play a crucial role in naive T-cell priming. Recent data suggested that natural killer (NK) cells can influence the capability of DCs to promote Th1 polarization. This regulatory function is primarily mediated by cytokines released in the microenvironment during inflammatory responses involving NK cells. In this study, we show that human NK cells exposed for short time to interleukin (IL)-12, IL-2, or IL-18, promote distinct pathways of Th1 priming. IL-12- or IL-2-conditioned NK cells induce maturation of DCs capable of priming IFN-gamma-producing Th1 cells. On the other hand, IL-18-conditioned NK cells induce Th1 polarization only when cocultured with both DCs and T cells. In this case, IL-2 released by T cells and IL-12 derived from DCs during the priming process promote interferon (IFN)-gamma production. In contrast, when NK cells are exposed to IL-4, nonpolarized T cells releasing only low levels of IL-2 are generated. Thus, the prevalence of IL-12, IL-2, IL-18, or IL-4 at inflammatory sites may differentially modulate the NK-cell interaction with DCs, leading to different outcomes in naive T-cell polarization.  相似文献   
36.
BACKGROUND: Electrophysiologically, ventricular fibrillation is defined as a "chaotic, random, asynchronous electrical activity of the ventricles due to repetitive re-entrant excitation and/or rapid focal discharge". To this point its morphological equivalent has not been defined. MATERIAL AND METHOD: Several groups of different diseases and types of accidental death in normal subjects were studied. A complete autopsy was performed and the hearts were examined in 432 cases. A total of 16 myocardial samples per heart were processed for histological examination and sections were stained by haematoxylin and eosin or by specific stains. The frequency, location and extent of myocellular segmentation (stretching and/or rupture) of intercalated discs and associated changes of myocardial bundles and single myocells were investigated. A quantitative analysis was performed and the data were processed for statistical evaluation. RESULTS: The frequency of MFB was maximal in coronary (88%) and Chagas (76%) groups followed by the intracranial brain haemorrhage group (52%). The extent of myofiberbreak-up was maximal in coronary/Chagas groups followed by intracranial haemorrhage and transplant groups. CONCLUSIONS: No correlation was seen between gender, age, heart weight, degree of coronary atherosclerosis, myocardial fibrosis, survival and MFB. If our postulate is correct, finding MFB in the myocardium might allow the diagnosis of a malignant arrhythmia followed by cardiac arrest due to ventricular fibrillation even in the absence of clinical information (sudden death out-of-hospital).  相似文献   
37.
A 67-year-old woman, who had symptoms of epigastric pain and abdominal distension, was found, on endoscopy, to have a large sessile villous adenoma of the periampullary duodenum. Despite the lack of evidence of malignancy, a pancreaticoduodenectomy procedure was performed, mainly because of the tumor size and site, involving the ampulla of Vater. The presence of the carcinoma was diagnosed only in the resected specimen by definitive histology. Because there is no general consensus on the optimal surgical procedure for the treatment of villous tumors of the duodenum, especially for the early stages, the indications for the operative procedure are discussed, based on a review of the literature.  相似文献   
38.
AIMS: Treatment delay is a powerful predictor of survival in ST-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI). We investigated effectiveness of pre-hospital diagnosis of STEMI with direct referral to PCI, alongside more conventional referral strategies. METHODS AND RESULTS: From January 2003 to December 2004, 658 STEMI patients were referred for primary PCI at our intervention laboratory. Three predefined referral routes were compared: (1) for patients within 90 min drive of the PCI centre, pre-hospital diagnosis and direct transportation (n=166), (2) diagnosis at the interventional hospital emergency department (n=316), (3) diagnosis at local hospitals before transportation (n = 176). Pre-hospital diagnosis was associated with more than 45 min reduction in treatment delay (P = 0.001). No significant difference in in-hospital mortality was apparent in the overall study population. In the cardiogenic shock subgroup (n = 80), pre-hospital diagnosis was associated with a two-thirds reduction in in-hospital mortality (P = 0.019); mortality was only 6.2% in shock patients who underwent PCI in < 2 h. CONCLUSION: This study shows that pre-hospital diagnosis can provide a reduction in primary PCI treatment delay, and suggests the hypothesis that this referral strategy might provide survival benefits to patients with cardiogenic shock.  相似文献   
39.
Introduction: Pelvic serous carcinomas (PSCs) are a controversial entity, which mostly comprise fallopian tube carcinoma (FTC), primary peritoneal carcinoma (PPC) and serous ovarian carcinoma (OC). Despite incremental attention towards understanding pelvic serous carcinogenesis, the gold standard treatment and survival rates have not substantially changed in these last decades.

Areas covered: This review summarizes and gives a critical overview of the ongoing Phase II trials investigating therapies for PSC.

Expert opinion: Several novel molecules have been developed and are currently under investigation for the treatment of PSC, including FTC, PPC and serous OC. The trend of novel targeted agents is one towards individualized, tailored therapy, based on the molecular and biological differences that characterize tumors that seem similar based solely on histological analysis. The task of developing new molecules is particularly difficult for PSC, given the recurrent development of new patterns of drug resistance. However, even if current research is focused towards identifying the best treatments for each woman with a molecularly defined disease, a deeper knowledge of the molecular biology and genetics underlying FTC and its relation as a precursor of PSC is needed.  相似文献   

40.
Background and objective: Several studies have reported an association between type 2 diabetes mellitus and hepatocellular carcinoma (HCC). Data from several retrospective studies and meta-analyses have highlighted a reduction of about 50% in the risk of developing HCC in cirrhotic patients treated with metformin for diabetes. The aim of this study was to evaluate the different outcomes of patients who received or did not receive metformin during treatment with sorafenib.

Methods: We analyzed 93 patients consecutively treated with sorafenib. Forty-two (45.2%) patients were diabetic, of whom 31 were on metformin. Progression-free survival (PFS) and overall survival (OS) were estimated with the Kaplan-Meier method and compared with the log-rank test.

Results: The concomitant use of sorafenib and metformin was associated with a median PFS of 2.6 months (95% CI 1.9–3.3) compared to 5.0 months (95% CI 2.5–8.2) for patients receiving sorafenib alone (p = 0.029). The median OS of patients treated with the combination was 10.4 months (95% CI 3.9–14.4) compared to 15.1 months (95% CI 11.7–17.8) for those who were not given metformin (p = 0.014).

Conclusions: Our findings could be the result of increased tumor aggressiveness and resistance to sorafenib in metformin-treated patients.  相似文献   

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