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991.
Non-invasive molecular detection of bladder cancer recurrence 总被引:7,自引:0,他引:7
Amira N Mourah S Rozet F Teillac P Fiet J Aubin P Cortesse A Desgrandchamps F Le Duc A Cussenot O Soliman H 《International journal of cancer. Journal international du cancer》2002,101(3):293-297
Transitional cell carcinoma (TCC) is the most common bladder tumor and approximately 90% of bladder TCC are superficial at initial diagnosis. High recurrence rate and possible progression to muscle invasive disease that is eventually indicated for radical cystectomy are established features of these tumors. Therefore, reliable predictors of tumor recurrence are of critical importance for management of superficial bladder TCC. Successful molecular diagnosis of bladder cancer by detecting genetic lesions: loss of heterozygosity (LOH) or microsatellite instability (MSI) in cells exfoliated in urine has been reported by several groups including ours. The aim of our study was to evaluate the predictive potential of microsatellite analysis of cells exfoliated in urine in the detection of superficial bladder TCC recurrence. We studied 47 Caucasian patients with confirmed superficial bladder TCC (37 pTa, 10 pT1) at initial diagnosis. Blood samples were obtained once from every patient whereas urine samples were collected before each cystoscopy (initial and follow-up). Matched DNAs from blood and urine were subjected to microsatellite analysis in a blinded fashion. The follow-up period ranged 12-48 months after tumor resection. Microsatellite analysis correctly identified 94% (44/47) of primary tumors and 92% (12/13) of tumor recurrences. Interestingly enough, 75% (9/12) of tumor recurrences were molecularly detected 1-9 months before cystoscopic evidence of recurrent disease. This study demonstrated clearly that not only urine microsatellite analysis reliably detected superficial bladder tumors, but also was a reliable test for detecting and predicting tumor recurrence in Caucasian patients. These results warrant multicenter randomized trials. 相似文献
992.
Janda M Stanek C Newman B Obermair A Trimmel M 《Breast cancer research and treatment》2002,73(1):37-43
Background Videotaped education materials to teach breast self-examination (BSE) are used worldwide. However, evaluation of videotaped BSE instructions is lacking.
Methods Premenopausal women (mean age 33.4±11.2 years) without history of breast cancer were approached to participate in this experimental study and randomly assigned to a video intervention group (VG; n=130; length of the video=15 min) or non-video comparison group (NVG; n=121). All participants answered a questionnaire on BSE behavior and health beliefs. No additional training was given. The total duration of the session including completion of the questionnaire was 15min for the NVG and 30min for the VG. Three months later, changes in BSE behavior were compared in the two groups. The influence of health beliefs on actual BSE behavior was investigated as well.
Results Women of both the VG and NVG performed BSE significantly more frequently at follow-up than at baseline. Analysis of covariance, using the baseline BSE-frequency as co-variate and the follow-up BSE frequency as the dependent variable, revealed that women in the VG (adjusted mean=7.9 times per year, 95%CI=6.5–9.4) performed BSE more frequently than women of the NVG (adjusted mean=6.1 times per year, 95%CI=4.6–7.5) (F=4.2, df=2, p=0.02). Among motivational predictors, having an example of a role model (modeling) was shown by regression analysis to explain the greatest amount of variance (13%) in BSE frequency.
Conclusion Use of an educational videotape increased the frequency of BSE among premenopausal women. 相似文献
993.
We analysed retrospectively 90 cases of invasive aspergillosis (IA) which occurred at the University Hospital and the Thoraxklinik gGmbH Heidelberg between 1991 and 1998. 71 cases were histologically proven, 19 were probable diseases. There were 49 male and 41 female patients, with a mean age of 51.5 years (range 16 days to 80 years). Underlying diseases were: hematological malignancies in 52% (n = 47; 24 with acute leukemia), solid organ transplantation (n = 11; 9 liver, 1 kidney, 1 heart), solid cancer (n = 10), others (n = 21), and in one case no underlying disease was diagnosed. Only 54 cases (60%) were correctly diagnosed as IA during lifetime of the patients. In 59 cases (65%) only the lung was affected, 25 patients suffered from disseminated IA, in 6 patients only extrapulmonary lesions were present. 11 patients underwent lung surgery, 63 patients received antimycotic drugs (44 amphotericin B, 15 fluconazole, 4 itraconazole), 21 were not treated antimycotically. 68 patients (71%) died, from these 30 (36%) due to IA during remission of the underlying disease. The laboratory methods showed the following sensitivities, respectively: microscopy by calcofluor white staining 17%, culture 69%, Aspergillus-PCR from respiratory tract samples and biopsies 95%, galactomannan antigen detection by latex agglutination 28%, by enzyme immunoassay 59%, Aspergillus antibody detection 23%. 相似文献
994.
Advanced rhythm discrimination for implantable cardioverter defibrillators using electrogram vector timing and correlation 总被引:3,自引:0,他引:3
Gold MR Shorofsky SR Thompson JA Kim J Schwartz M Bocek J Lovett EG Hsu W Morris MM Lang DJ 《Journal of cardiovascular electrophysiology》2002,13(11):1092-1097
INTRODUCTION: Discrimination of ventricular and supraventricular arrhythmias remains one of the major challenges for appropriate implantable defibrillator (ICD) therapy delivery. The electrogram vector timing and correlation (VTC) algorithm was developed for such rhythm discrimination. The VTC algorithm differentiates normally conducted supraventricular beats from abnormally conducted ventricular beats by comparing the timing and correlation of rate and shock channel electrograms. METHODS AND RESULTS: Rate and shock channel electrograms of sinus rhythm and induced arrhythmias were collected from 93 patients during ICD placement. The algorithm was developed using data from 50 patients and prospectively tested in a software model with the remaining 43 patients. A sinus rhythm reference was formed by averaging complexes of the shock channel signal aligned by the peak amplitude of the rate channel. Eight features measuring the amplitude and timing of shock channel signal characteristics were extracted from the reference for comparison. When a high-rate rhythm was detected, the VTC algorithm computed the correlation of the arrhythmia complex features with the reference. Rhythms with a sufficient number of uncorrelated beats were classified as ventricular tachycardia (VT). In a dual-chamber implementation, the VTC algorithm is integrated with ventricular and atrial rate comparison (V>A) and stability above an atrial fibrillation rate threshold. The test set consisted of 117 arrhythmias. Dual-chamber sensitivity was 100% (81/81 VT) and specificity was 97% (35/36 supraventricular tachycardia). Single-chamber analysis demonstrated 99% sensitivity and 97% specificity. CONCLUSION: The VTC algorithm demonstrated high sensitivity and specificity in discriminating between ventricular and supraventricular arrhythmias. 相似文献
995.
Rossi BM Lopes A Oliveira Ferreira F Nakagawa WT Napoli Ferreira CC Casali Da Rocha JC Simpson CC Simpson AJ 《Annals of surgical oncology》2002,9(6):555-561
Background The aim of this study was to search for mutations in the humanmutS homolog 2 (hMSH2) and humanmutL homolog 1 (hMLH1) genes in 25 unrelated Brazilian kindreds with suspected hereditary nonpolyposis colorectal cancer (HNPCC).
Methods The families were grouped according to the following clinical criteria: Amsterdam I or II; familial colorectal cancer (CRC);
an early age of onset of CRC in the proband only; or with at least one or two relatives who had HNPCC-related cancers; CRC
in the proband only. All patients were studied with direct sequencing.
Results Ten mutations were detected (10 of 25 [40%]); of nine different mutations, seven were novel. ThehMLH1 gene had a higher mutation detection rate thanhMSH2 (8 of 25 [32%] vs. 2 of 25 [8%]). Only 3 of these 10 families fulfilled the Amsterdam criteria. Two different polymorphisms
were detected in thehMLH1 gene and four in thehMSH2 gene.
Conclusions ThehMLH1 gene had a higher mutation detection rate thanhMSH2. The physician who deals with CRC must take into consideration the heredity issue with patients who present with an early
age of onset or a familial history of CRC- or HNPCC-related cancers, including gastric cancer, even if they do not fulfill
the former Amsterdam criteria. 相似文献
996.
目的 建立双引物聚舍酶链反应(PCR)用于同时快速检测梅毒螺旋体和单纯疱疹病毒Ⅱ型。方法 基于单纯疱疹病毒Ⅱ型(HSV-2)的DNA聚合酶基因以及梅毒螺旋体47KD膜蛋白基因序列,自行设计2对特异性寡核苷酸引物,建立了同时检测上速2种痛原体的双引物PCR。结果 各特异性引物仅扩增相应的病原体DNA,即单纯疱疹病毒Ⅱ型扩增产物为202bp以及梅毒螺旋体扩增产物为252bp。其他11种生殖道常见微生物及正常人基因组DNA不被扩增。检测了51例临床标本,梅毒螺旋体暗视野显微镜检查阳性检出率为15.7%,双引物PCR阳性检出率为19.6%;二种方法检测结果间比较差异均无统计学意义(P〉0.05)。HSV阳性培养率23.6%,双引物PCR阳性率47.1%,双引物PCR阳性检出率显著高于HSV培养且差异有统计学意义(P=0.019);上速临床标本分别进行了2种痛原体的单引物PCR,与双引物PCR对照结果完全一致。结论 我们建立的双引物PCR一次可同时检测2种病原体,且有快速、敏感、特异以及简便的特点。 相似文献
997.
998.
呼吸机相关性肺炎常见病原菌及其耐药性的临床分析 总被引:8,自引:0,他引:8
目的 探讨机械通气患者呼吸机相关性肺炎(VAP)的致病菌群及药敏结果。方法 分析78例VAP临床资料及呼吸道分泌物细菌培养的结果。结果 VAP发生率为52.7%,病原菌以革兰阴性菌为主,占菌株总数的74.8%,鲍曼不动杆菌、肺炎克雷伯菌、铜绿假单胞菌、金黄色葡萄球菌是VAP的主要致病菌,大多数革兰阴性菌对常用抗菌药物已表现出较高的耐药率。结论 应重视对VAP的病原学监测,以提高临床诊断与治疗水平。 相似文献
999.
目的:建立一种简便、快速的高效液相色谱(HPLC)荧光检测法测定人体内血浆中氟伐他汀的浓度。方法:采用Kromasil C18柱(4.6mm×150mm,5μm),柱温40℃,流动相为13mmol·L-1澳化四丁基铵-乙腈(51:49,V/V),流速为1.0mL·min-1,荧光检测激发波长305nm,发射波长405nm。结果:氟伐他汀在1-1000μg·L-1范围内线性关系良好(r=0.9994)。日内和日间RSD均低于10%。结论:该方法灵敏度高、快速、简便、无杂质干扰,适合于氟伐他汀的体内分析和人体药动学研究。 相似文献
1000.
Previous studies have shown that the nucleus of the basal optic root in birds is involved in optokinetic nystagmus, and its neurons respond not only to large-field stimuli but also to a single object moving through their excitatory receptive fields. The present study provides electrophysiological evidence that basal optic neurons in pigeons respond vigorously to motion of a black leading edge. The orientation of the edge is also an essential factor affecting visual responses of these cells, showing that any deviation of the edge from the direction perpendicular to the preferred direction decreases visual responses in most cases. Furthermore, visual responses increase as the edge is lengthened within the excitatory receptive field. However, a square, semicircle and isosceles with an area ratio of 1.00: 0.39: 0.50 but with an identical leading edge elicit almost the same responses, which are not dependent on the shape and area of visual stimuli. It suggests that these feature extraction properties, similar to those of neurons in the nucleus lentiformis mesencephali, may be specialized for detecting optokinetic stimuli rich in luminance contrasts, but not for realizing pattern recognition. 相似文献