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61.
BACKGROUND: Tumor necrosis factor related apoptosis-inducing ligand/Apo2 ligand (TRAIL/Apo-2L) is a novel anticancer agent, capable of inducing apoptosis preferentially in tumor and transformed cells. TRAIL-R1/death receptor (DR)4 and TRAIL-R2/DR5 are members of the tumor necrosis factor (TNF) receptor family, and can be activated by the TRAIL. We examined the clinical potential of chemotherapeutic drugs and TRAIL for the treatment of prostate cancer. METHODS: Prostate and bladder cancer cells were exposed to chemotherapeutic drugs (paclitaxel, vincristine, vinblastine, etoposide, doxorubicin, and camptothecin) and TRAIL. Cell viability was measured by sodium 3'[1-(phenylaminocarbonyl)-3,4-tetrazolium]-bis (4-methoxy-6-nitro) assay; expressions of death receptors and Bcl-2 family members were measured by Western blotting, ELISA and ribonuclease protection assay. PC-3 tumor cells xenografted athymic nude mice were exposed to chemotherapeutic drugs and TRAIL, either alone or in combination, to measure tumor growth and survival of mice. Apoptosis was measured by annexin V-FITC/propidium iodide staining, and terminal deoxynucleotidyltransferase-mediated nick end labeling assay. Caspase-3 activity was measured by the Western blotting and immunohistochemistry. RESULTS: TRAIL induced apoptosis with varying sensitivity. Chemotherapeutic drugs (paclitaxel, vincristine, vinblastine, etoposide, doxorubicin, and camptothecin) significantly augmented TRAIL-induced apoptosis in cancer cells through up-regulation of DR4, DR5, Bax, and Bak, and induction of caspase activation. Mitochondrial pathway enhanced the synergistic interactions between drugs and TRAIL. The sequential treatment of mice with chemotherapeutic drugs followed by TRAIL induced caspase-3 activity, and apoptosis, inhibited angiogenesis, completely eradicated the established tumors, and enhanced survival of mice. CONCLUSIONS: Chemotherapeutic drugs can be used to enhance the therapeutic potential of TRAIL in prostate cancer.  相似文献   
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OBJECTIVE: To present our experience with buccal mucosa urethroplasty for substitution of all segments of the anterior urethra, as the buccal mucosal graft (BMG) has emerged as the tissue of choice for single-stage reconstruction of bulbar urethral strictures, but its use for reconstructing meatal, pendulous and pan-urethral strictures has not been widely reported. PATIENTS AND METHODS: Between January 1998 and October 2003, 92 patients had a BMG substitution urethroplasty at our institution; 75 had a single-stage dorsal onlay BMG urethroplasty (bulbar 41, pendulous 16 and pan-urethral 18; six combined penile skin flap and BMG) and 17 (pendulous five, pan-urethral 10, bulbar two) a two-stage urethroplasty. Recurrence rates, complications and cosmetic outcomes were analysed retrospectively. RESULTS: Over a median (range) follow-up of 34 (8-72) months, 66 (88%) patients with a one-stage reconstruction (14/16 pendulous; 37/41, 90%, bulbar; 15/16 pan-urethral) remained stricture-free. The mean (range) time to recurrence was 9.4 (3-17) months. Of the nine recurrent strictures, six were managed by one-stage optical urethrotomy and three required a repeat urethroplasty. In patients who had a staged procedure, after a mean follow-up of 24.2 (9-56) months, one had complete graft loss, requiring re-grafting, five required stomal revision after stage 1, and only two (12%) developed a recurrent stricture after the two-stage urethroplasty. CONCLUSION: A one-stage dorsal onlay BMG urethroplasty provides excellent results for strictures involving any segment of the anterior urethra. The BMG appears to be the most versatile urethral substitute, as it can be successfully used for both one- and two-stage reconstruction of the entire anterior urethra.  相似文献   
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This paper presents an effective application of backpropagation artificial neural network (ANN) in differentiating electroencephalogram (EEG) power spectra of syncopic and normal subjects. Digitized 8-channel EEG data were recorded with standard electrodes placement and amplifier settings from five confirmed syncopic and five normal subjects. The preprocessed EEG signals were fragmented in two-second artifact free epochs for calculation and analysis of changes due to syncope. The results revealed significant increase in percentage δ and α (p<0.5 or better) with significant reduction in percentage θ activity (p<0.05). The backpropagation ANN used for classification contains 60 nodes in input layer, weighted from power spectrum data from 0 to 30 Hz, 18 nodes in hidden layer and an output node. The ANN was found effective in differentiating the EEG power spectra from syncopic EEG power spectra and the normal EEG power spectra with an accuracy of 88.87% (85.75% for syncopic and 92% for normal). Certificate of Originality—This is to certify that the article submitted for publication in ‘Journal of Medical Systems’ has not been publ-ished, nor is being considered for publication, elsewhere. (Rakesh Kumar Sinha)  相似文献   
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Small bowel perforations with peritonitis pose a serious problem to an emergency surgeon because of the lack of any uniformity of opinion regarding the optimum surgical treatment to be performed. This may be attributed to lack of any common and reliable scoring system. A prospective study to discover the utility of APACHE-II triaging in small bowel perforations was conducted over a period of 14 months on 51 patients with small bowel perforations of various aetiologies. The triaging facilitated definitive surgical treatments based on the predictive value of APACHE-II scoring. The classification of patients into three groups, effectively brought uniformity in the management. A significant reduction in mortality and cost-effective utilization of scarce intensive care unit resources were the dominant outcomes of this study conducted at a busy tertiary centre.  相似文献   
67.
The results of primary coronary stenting for acute myocardial infarction (AMI) have been reported to improve significantly with the concomitant administration of platelet glycoprotein IIb/IIIa inhibitor abciximab. There are, however, no data available with the use of eptifibatide, a more cost-effective, small-molecule GP IIb/IIIa blocker with a shorter half-life. In a prospective multicenter feasibility and efficacy study, we assigned 55 consecutive patients with AMI being taken up for primary stenting to receive eptifibatide just before the procedure (two boluses of 180 microg/kg 10 min apart and a 24-hr infusion of 2 microg/kg/min). Clinical outcomes were evaluated at 30 days after the procedure. The angiographic patency of the vessel with TIMI flow rates, TIMI myocardial perfusion (TMP) grade, and corrected TIMI frame counts were assessed at the end of procedure and before hospital discharge. At 30 days, the primary endpoint, a composite of death, myocardial infarction, and urgent target vessel revascularization (TVR) was seen in 12.7% of patients. The TIMI 3 and TMP grade 3 flow, which was seen in 93% and 86% of patient, respectively, at the end of the procedure, declined to 86% and 78%, respectively (P < 0.05) before hospital discharge. Corrected TIMI frame counts also decreased from 25.7 +/- 7.2 to 22.9 +/- 6.8 (P < 0.05). There were five (9.1%) instances of subacute thrombosis (SAT) presenting as AMI, needing urgent TVR in all, within 3-5 days of the primary procedure. No excessive bleeding complication, directly attributable to the use of eptifibatide, was observed. The study was terminated prematurely because of an unacceptable SAT rate. Administration of eptifibatide along with primary stenting for AMI is associated with a high TIMI 3 and TMP grade 3 flow acutely. However, these flows decline significantly before hospital discharge and lead to a high rate of SAT. The dosage and duration of infusion of eptifibatide in this setting needs further evaluation.  相似文献   
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Acute graft‐versus‐host disease (GVHD) is a common and serious complication of allogeneic blood and marrow transplantation. Acute GVHD is commonly graded according to modified Glucksberg criteria. There is considerable within‐grade heterogeneity with different patterns of skin, liver, or gut involvement. In this commentary, we provide an analytical review of ambiguities in acute GVHD severity scoring and offer specific proposals meant to generate discussion in the BMT community for adoption, refinement, and where appropriate, validation studies.  相似文献   
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