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91.
Patients with locally advanced transitional cell carcinoma (TCC)of the bladder are at high risk forsystemic relapse, with liver, bone and lung beingthe commonest sites of metastases.We report the case of a 52-year-old womanwith a solitary meningeal relapse, a rare siteof recurrence, after 8 months of complete remissionobtained with M-VEC for locally advanced TCC ofthe bladder. We speculate on the likely riskfactors related to this unusual site of recurrence.  相似文献   
92.
Cell kinetics parameters have been analysed in colonic mucosa at different distances from a tumour in patients with colon carcinoma. Total cell number (TCN), H thymidine labelling index (TLI), mitotic index (MI), Goblet cell index (GCI) and the distribution of labelled cells along the crypt column (cell position frequency plot) were determined in well-aligned crypts. Total cell number, GCI and the labelled cell position frequency plots were similar in different samples from the same individual. A negative linear correlation between TCN and TLI was observed. The analysis of the cell position plots showed two patterns 1) with a high concentration in the bottom fifth of the crypt and 2) with frequent labelled cells at high positions. Whereas a negative correlation between overall TLI and the percent contribution to the TLI of the lowermost fifth was seen, the correlation was positive for the next 3 fifths and labelling was absent in the last part of the crypt.  相似文献   
93.
BACKGROUND: Despite the clinical efficacy of percutaneous transmyocardial revascularization (PTMR), up to date there are still no instrumental validations to demonstrate both the improved perfusion of treated areas and cardiac function. METHODS: During the first year of follow-up after PTMR, 27 patients (group A) underwent 99mTc MIBI exercise-single photon emission tomography (SPET), while 30 patients (group B) underwent serial transthoracic echocardiography (TTE) evaluations with analysis of cardiac volumes and subendocardial layer thickness in systole. RESULTS: All 57 patients had a significant angina Canadian Cardiovascular Society (CCS) class improvement. Group A patients (75%) had improved exercise-SPET perfusion in treated areas at 12 weeks after PTMR, and at the next follow-up. Group B patients had non-significant reduction in global volume and no significant change in ejection fraction. However, there was an improvement in thickness of the subendocardial-treated areas in systole that persisted during follow-up. CONCLUSIONS: The use of SPET and TTE validates the clinical efficacy of PTMR.  相似文献   
94.
95.
A two arm multicentre randomized controlled trial is in progress to evaluate the efficacy of flexible sigmoidoscopy (FS) as a screening test for colorectal cancer in the general population. AIMS: To determine the acceptance rate and feasibility of FS as a colorectal cancer screening test in average-risk asymptomatic volunteers. Average-risk, asymptomatic subjects, aged 55-64 years and assisted by 244 general practitioners (GPs) in Lombardy, Italy, were invited by postal questionnaire (PQ) to enter a study for the prevention of colorectal cancer and asked to indicate their interest in, and willingness to undergo, screening: those responding positively were randomized to the intervention or control arms. GPs were trained in colorectal cancer screening and proposed free FS to their patients randomized to the intervention arm. All sigmoidoscopies were performed by experienced endoscopists. Small polyps were removed at FS. Colonoscopy was indicated for high risk polyps (size more than 5 mm, more than two adenomas, villous histology, severe dysplasia or malignancy). 40,945 subjects were invited. 667 PQs were returned undelivered due to postal failure. 7,892 (19.59%) subjects responded, 2,116 of whom (26.81%) were not included, presenting 1 or more exclusion criteria. We randomized 5,778 volunteers and performed 1,582 sigmoidoscopies out of 2,885 subjects in the intervention arm (54.84% acceptance rate). Although the screening procedure had a good attendance rate in the intervention group, involvement of the people invited was lower than expected. Future FS screening programmes will require a keener focus on recruitment strategies, mainly with participation of GPs.  相似文献   
96.
BACKGROUND AND PURPOSE: To appraise the potential benefit of a conformal technique with non-coplanar fields to minimise lung irradiation in the radiation treatment of breast. PATIENTS AND METHODS: A comparative study was carried out at planning level for six patients selected for their inadequate sparing of healthy lung tissue with the reference tangential technique. Plans were designed for the conventional tangential technique, for an alternative conformal approach with three beams and for the newly proposed technique with two non-coplanar beams. RESULTS: In average for the new technique compared to the reference, mean lung dose dropped from approximately 16 to 10.5 Gy, V(20 Gy) from 29.5 to 18.2% and the dose delivered to 1/3 (1/4) of the lung volume dropped from 28.5% (67.3%) to 8.7% (13.4%). For PTV, the volume receiving at least 90% of the prescribed dose resulted 97.4% for the new and 97.3% for the reference. Conformity index improved significantly from 2.58 for the reference to 1.84 for the new technique. CONCLUSIONS: For a subgroup population of breast cancer patients, where conventional techniques failed to achieve high conformal avoidance, a treatment modality with non-coplanar beams was developed and clinically tested for six patients. It resulted dosimetrically adequate, particularly when the risk of toxicity is relevant.  相似文献   
97.
PURPOSE: Between September 1991 and May 1997, within the International Berlin-Frankfurt-Muenster Study Group (I-BFM-SG), a randomized study was performed aimed at assessing the efficacy of prolonged use of high-dose l-asparaginase (HD-l-ASP) during continuation therapy in children with standard risk (SR) acute lymphoblastic leukemia (ALL), treated with a reduced BFM-type chemotherapy. PATIENTS AND METHODS: The Italian, Dutch, and Hungarian groups participated in this study denominated IDH-ALL-91, and 494 children were enrolled. Treatment consisted of a BFM-type modified backbone with omission of the IB part in induction and elimination of two doses of anthracyclines during reinduction in both arms at the beginning of continuation therapy. Patients were randomly assigned to receive (YES-ASP) or not (NO-ASP) 20 weekly HD-l-ASP (25,000 IU/m2). RESULTS: The event-free-survival and overall survival probabilities at 10 years for the entire group were 82.5% (1.8) and 90.3% (1.3), respectively. Of the 490 patients eligible for random assignment, 355 (72.4%) were randomly assigned (178 YES-ASP and 177 NO-ASP). After a median follow-up of 9 years, the probability of disease-free survival at 10 years was 87.5% (SE, 2.5) for YES-ASP arm versus 78.7% (SE, 3.3) for NO-ASP arm (P = .03). In multivariate analysis, NO-ASP arm (P = .03), male sex (P = .004), and age older than 10 years (P = .0003) had a significantly adverse impact on outcome. CONCLUSION: In this subset of patients, selected with criteria not including monitoring of minimal residual disease, application of extended HD-l-ASP may improve prognosis, compensating reduced leukemia control that results from adoption of a reduced-intensity BFM-backbone for treatment of children with SR ALL.  相似文献   
98.
Mucoepidermoid Carcinoma (MEC) it can origin from a mandibular odontogenic cyst. We report the case of a 63‐year‐old man with MEC of the right retromolar trigonum of the mandibula. We performed a wide mandibular excision and immediate reconstruction with a fibula bone free flap.  相似文献   
99.
100.
Deep vein thrombosis results from the cooperative action of leukocytes, platelets, and endothelial cells. The proline-rich tyrosine kinase Pyk2 regulates platelet activation and supports arterial thrombosis. In this study, we combined pharmacological and genetic approaches to unravel the role of Pyk2 in venous thrombosis. We found that mice lacking Pyk2 almost completely failed to develop deep venous thrombi upon partial ligation of the inferior vena cava. Pyk2-deficient platelets displayed impaired exposure of phosphatidylserine and tissue factor expression by endothelial cells and monocytes was completely prevented by inhibition of Pyk2. In human umbilical vein endothelial cells (HUVEC), inhibition of Pyk2 hampered IL-1β-induced expression of VCAM and P-selectin, and von Willebrand factor release. Pyk2-deficient platelets showed defective adhesion on von Willebrand factor and reduced ability to bind activated HUVEC under flow. Moreover, inhibition of Pyk2 in HUVEC strongly reduced platelet adhesion. Similarly, Pyk2-deficient neutrophils were unable to efficiently roll and adhere to immobilized endothelial cells under venous flow conditions. Moreover, platelets and neutrophils from Pyk2-knockout mice showed defective ability to form heterogeneous aggregates upon stimulation, while platelet monocyte interaction occurred normally. Consequently, platelet neutrophil aggregates, abundant in blood of wild-type mice upon inferior vena cava ligation, were virtually undetectable in Pyk2-knockout mice. Finally, we found that expression of Pyk2 was required for NETosis induced by activated platelets. Altogether our results demonstrate a critical role of Pyk2 in the regulation of the coordinated thromboinflammatory responses of endothelial cells, leukocytes and platelets leading to venous thrombosis. Pyk2 may represent a novel promising target in the treatment of deep vein thrombosis.  相似文献   
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