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Sensitivity of cervical cytology is suboptimal, especially in developing countries such as Mexico, despite available guidelines aimed at improving this. When obtaining cervical samples, whether the samples are taken from the transformation zone and whether abnormal cells are missing must be considered. Cervical secretions (CS) are always present in variable proportions, and when cleaning the cervix, better samples may be obtained. In this study, we analyzed samples obtained with or without cleaning the cervix, and compared their contents in order to determine the sensitivity and specificity of these two methods. Methods: Of 500 patients who underwent cytology and colposcopy, 271 (54.2%) required a second opinion due to a diagnosis of cervical intraepithelial neoplasia (CIN). CS was removed and compared with the clean, second sample (SS) using in both liquid-based cytology. The quality of samples according to the Bethesda System, the presence of CIN, and inflammatory reactions were recorded. The sensitivity and specificity were calculated using biopsy as the gold standard. Results: The SS resulted in a higher proportion of adequate samples being obtained (97.6% vs. 44.8%), and in increased sensitivity (88.2% vs. 58.8%). CIN was detected in the SS 26% more often than in the CS (34 vs. 27 samples), whereas inflammatory reactions were noted more often in the CS (91.4% vs. 74%). Conclusion: Cervical sampling including CS results in lower sensitivity and CIN detection rates, and in more inflammatory reactions. By excluding CS from cervical samples, the sensitivity could be improved and the false negative rate could be reduced.  相似文献   
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Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis in tumour cell lines. Four membrane-bound receptors for TRAIL have been identified, two apoptosis-mediating receptors, DR4 and DR5, and two apoptosis-inhibiting receptors, DcR1 and DcR2. The aim of this study was to examine the role of TRAIL and its receptors in colorectal cancer development. The immunohistochemical expression and localization of TRAIL and its receptors were investigated in normal mucosa (n=10), adenomas (n=19), and carcinomas (n=21). Correlations between the expression of TRAIL and its receptors and the degree of apoptosis (assessed by M30 expression) and histopathological characteristics were explored. TRAIL and its receptors were expressed in normal mucosal epithelium. Expression of the receptors was seen in adenomas and carcinomas. TRAIL expression was lost in a subset of colorectal tumours, more frequently in carcinomas than in adenomas (p<0.05). DR4 and DR5 staining was stronger in neoplastic cells than in normal cells and was accompanied by a higher degree of apoptosis. No differences were found between tumour and normal cells regarding DcR1 and DcR2 expression. No correlations were found between TRAIL or TRAIL receptor expression and histopathological characteristics. In conclusion, marked changes were seen in the course of the adenoma-carcinoma sequence with respect to the expression of TRAIL and TRAIL receptors DR4 and DR5. The stronger expression of DR4 and DR5 in neoplastic cells than in normal cells, together with a higher degree of apoptosis, suggests a possible functional role for these receptors in apoptosis induction in neoplastic colorectal cells.  相似文献   
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PurposeRenal function outcomes following robot-assisted radical cystectomy (RARC) have not been well established. We sought to compare long-term renal function outcomes between open radical cystectomy, RARC with extracorporeal urinary diversion and intracorporeal urinary diversion at a high volume institution.Materials and MethodsWe retrospectively reviewed our institutional bladder cancer database for patients who underwent RC from 2010 to 2019 with pre-operative estimated glomerular filtration rate (eGFR) > 45 ml/min/1.73m2. Changes in renal function were assessed through locally weighted scatter plot smoothing and comparison of median eGFR between surgical groups. Chronic Kidney Disease Stage 3B was defined as eGFR < 45 ml/min/1.73m2. Renal function decline was defined as a ≥10 ml/min/1.73m2 drop in eGFR. Kaplan Meier method with log-rank was used to compare CKD 3B-free survival and renal function decline. Cox Proportional Hazards model was used to identify predictors of CKD 3B.ResultsSix hundred and forty four patients were included with median follow-up of 32 months (IQR 12–56). Preoperative characteristics were similar among the groups with no differences in median pre-operative eGFR (ORC: 74.6, extracorporeal urinary diversion: 74.3, intracorporeal urinary diversion: 71.6 ml/min/1.73m2, P = 0.15). Median postoperative eGFR on follow up was not different between groups (P = 0.56). 33% of patients developed CKD 3B. There were no differences in CKD 3B-free survival by surgical approach (P = 0.23) or urinary diversion (P = 0.09). 64% of patients experienced renal function decline with a median time of 2.4 years (P 0.23). Predictors of CKD were pathologic T3 disease or greater (HR: 1.77, P = 0.01), ureteroenteric anastomotic stricture (HR: 2.80, P < 0.001), preoperative CKD Stage 2 (HR: 1.81, P =0.02), and preoperative CKD Stage 3A (HR: 5.56, P < 0.001).ConclusionRenal function decline is common after RC. Tumor stage, pre-operative eGFR, and ureteral stricture development, not surgical approach, influence renal function decline.  相似文献   
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Kunin  M; Phillips  JJ; Schwarz  G 《Radiology》1988,167(1):271-273
A dot-screen pattern was devised and superimposed on computed tomography images to improve contrast at a viewbox. The phenomenon is believed to be probably related to lateral inhibition. To evaluate its usefulness, the device was used on 12 images (eight showed metastatic liver lesions, and four were normal); each image was viewed without the device by ten observers. Three control images were viewed a second time without the device. The remaining nine images were viewed a second time with the device. The overlay improved diagnostic performance in nine observers. Sensitivity improved by 12%, and confidence in true-positive findings increased by 41.6%. Forty-five percent of false-negative findings were converted to true positive with the use of the overlay.  相似文献   
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Carpentieri  U; Minguell  JJ; Gardner  FH 《Blood》1981,57(5):975-978
Adenylate cyclase (AC) and guanylate cyclase (GC) activities were studied in normal B-enriched and T-enriched lymphocytes, in lymphocytes of children with acute lymphocytic leukemia (ALL), and in lymphocytes of adults with chronic lymphocytic leukemia (CLL). AC activity was greater in normal B than T lymphocytes (215 pmole/min/mg protein versus 80 pmole in the membrane-enriched fraction) and i both increased greatly after stimulation with isoproterenol and more so with prostaglandins E and F2 alpha. In leukemic lymphocytes, AC showed depressed activity (20 pmole in ALL cells and 55 pmole in CLL cells) and was less sensitive to hormonal stimulation: this loss of sensitivity occurred to a greater extent in ALL than in CLL lymphocytes. GC activity was greater in normal T than B cells (in membrane-enriched fraction: 10.2 pmole versus 5.3 pmole). It increased little with isoproterenol and prostaglandins stimulation, and much more with sodium azide and dehydroascorbic acid stimulation. GC activity was increased in both types of leukemic lymphocytes (23 pmole for ALL cells and 18 pmole for CLL cells) and was insensitive to stimulation. Possible derangement of cyclase and cyclic nucleotide regulation in leukemic cells is suggested.  相似文献   
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Guillain-Barr啨综合征(GBS)和Miller Fisher综合征(MFS)的诊断标准随着临床研究的深入在不断演变。2011年1月,《疫苗》杂志发表了国际疫苗安全性监测Brighton合作组关于GBS/MFS的诊断定义和研究资料收集规范。此文献中未采用"诊断标准"而采用"诊断定义"是因为其主要目的为评价疫苗安全性而制定,而非用于神经科的GBS/  相似文献   
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