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91.
The principles of urology and all surgical disciplines were, not too long ago, considered to be rigidly and permanently established. In this exciting era of change, the foundations of urology are now set on shifting sands rather than the bedrock of the past. The pertinent issue clinically is making discriminating evaluations of new developments so that, where appropriate. they are able to be incorporated into treatment practices to improve patient care. In this overview, a personal appreciation of the more important practical and conceptual changes relating to prostatic. urothelial and renal carcinoma during the past 5 to 10 years is presented.  相似文献   
92.
目的 研究支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌 (NSCLC)的可行性及临床价值。方法  76例NSCLC患者随机分成A、B 2组 ,A组先行 2次支气管动脉灌注化疗 (BAI) ,第 2次BAI 1~ 2周后再行直线加速器放射治疗 (RT) ;B组单纯行 2次BAI (对照组 )。结果 临床疗效 ,A组 (BAI RT)和B组 (BAI)分别为 89.47%和 60 .5 3% (Ρ <0 .0 1) ;1、3年生存率 ,A、B组分别为 81.5 8%、5 0 .0 0 %和 60 .5 3%、2 1.0 5 % ( 0 .0 1<Ρ <0 .0 5 )。结论 支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌的临床疗效和患者 1、3年生存率均显著提高  相似文献   
93.
Specific receptors for bombesin/gastrin releasing peptide (GRP) on the androgen-independent human prostate cancer cell lines PC-3 and DU-145 were characterized. No specific binding of 125I-[Tyr4]-bombesin to the androgen-dependent human prostate cancer cell line LNCaP was detectable. The binding of 125I-[Tyr4]-bombesin to PC-3 and DU-145 cells was found to be time- and temperature-dependent, saturable, and reversible. Scatchard analysis revealed a single class of binding sites with high affinity (Kd 9.8 × 10?11 M for PC-3, and 9.1 × 10-11 M for DU-145 cells at 25°C) and with a binding capacity of 44,000 binding sites/cell and 19,000 binding sites/cell, respectively. Bound 125I-[Tyr4]-bombesin was rapidly internalized by PC-3 cells. The nonhydrolyzable GTP analog GTP-gamma-S caused a dose-dependent inhibition of 125I-[Tyr4]-bombesin binding to PC-3 and DU-145 cells, indicating that a G-protein (guanine nucleotide-binding protein) couples the bombesin receptor to intracellular effector systems. Bombesin and GRP(14-27) inhibited the binding of 125I-[Tyr4]-bombesin to both cell lines in a dose-dependent manner with inhibition constants (Ki of 0.5 nM and 0.4 nM, respectively. Both cell lines express the bombesin/GRP preferring bombesin receptor subtype, since, in displacement studies, neuromedin B was more than 200 times less potent than bombesin and GRP(14-27) in inhibiting the binding of 125I-[Tyr4]-bombesin. Two synthetic bombesin/GRP antagonists, RC-3095 and RC-3110, powerfully inhibited the specific binding of 125I-[Tyr4]-bombesin with Ki 0.92 nM and 0.26 nM on PC-3 cells, and 3.3 nM and 0.89 nM on DU-145 cells, respectively. These findings indicate that the PC-3 and DU-145 human prostate cancer cell lines possess specific high-affinity receptors for bombesin/GRP, and are suitable models for the evaluation of the antineoplastic activity of new bombesin/GRP antagonists in the treatment of androgen-independent prostate cancer. © 1994 Wiley-Liss, Inc.  相似文献   
94.
Current clinical staging, which includes the use of serum tumor markers and imaging techniques, fails to identify the 30–40% of clinical stage I (CS I) nonseminomatous germ cell testicular tumor (NSGCT) patients who have occult metastatic disease. Therefore, there is a real clinical need to evaluate new biological parameters of the primary tumor that might be useful as predictors of occult metastatic disease. This study was undertaken to compare quantitative DNA measurements by flow cytometry and image analysis in CS I NSGCT, and to analyze the relevance of these parameters for predicting occult lymph node involvement. Different blocks of formalin-fixed, paraffin-embedded NSGCTs of 62 CS I patients who underwent retroperitoneal lymph node dissection between 1985 and 1989 were prepared according to the Hedley technique, and analyzed by quantitative cytometry. Thirty-six (58.1%) patients had histologically proven lymph node involvement (pathological stage II), whereas 26 (41.9%) patients (pathological stage I) had neither lymph node metastases according to retroperitoneal lymph node dissection (RPLND) specimens nor tumor recurrence during follow-up. Concordant results were found in 76.5% of the samples by both cytometric techniques. For flow cytometry, the percentages of aneuploid cells in the S- and the G2M+S-phase were the most robust predictive parameters for lymph node involvement, whereas for image analysis the 5c exceeding rate (5cER) had the most predictive significance. Based on the experience obtained in this study, both cytometric techniques provide additional information on tumor aggressiveness that might be useful in therapeutic selection of early stage NSGCT patients for either RPLND or surveillance only.  相似文献   
95.
Summary Prosthetic materials, such as metals, marlex mesh and methyl methacrylate have been used for stabilization of the chest wall after resection of large areas of rib cage. Such materials are contraindicated in an infected area. A new method of providing a stable chest wall using autogenous tissue is presented.  相似文献   
96.
我们用卡介苗(BCG)直接作用于体外培养膀胱癌细胞株,用扫描电镜和相差显微镜观察,癌细胞形态学发生明显变化,癌细胞表面结构损伤严重,微绒毛和长突起消失,残存畸变,小球密集成片,肿瘤表面结构与胞体分离,癌细胞生长抑制曲线表明,癌细胞的生长抑制率随着时间延长和BCG浓度增大而增高。实验证明,BCG对膀胱细胞有直接损伤作用。  相似文献   
97.
AgNOR计数在肺癌诊断及肺腺癌分型中的应用研究   总被引:4,自引:0,他引:4  
《中国医科大学学报》1995,24(2):132-134
  相似文献   
98.
The results of external beam radiotherapy for clinically localized adenocarcinorna of the prostate in 448 patients treated in the period 1980–90 were reviewed. The average follow up was 4.9 years. The patients were aged 44–87 years (median 69 years) and all had histopathological evidence of adenocarcinoma by needle biopsy or transurethral resection of prostate. The histopathological grading was: 127 G1; 154 G2; 127 G3; 12 G4; 28 Gx. Clinical staging according to TNM (American Urological Association) was: 29 T0 (A2); 4 T1 (B1); 173 T2 (B2); 176 T3 (C1); 63 T4 (C2); 3 Tx. Routine surgical pelvic lymph node staging was not performed but patients had radiological (computerized tomography scan or lymphogram) nodal staging: 350 N0; 22 N1; 12 N2; 64 Nx. High energy linear accelerator external beam radiotherapy was given by multiple fields to total doses of 50–70 Gy (median 60 Gy). The majority of patients (307, 69%) was treated by a uniform policy under the care of one radiation oncologist (HM). The rates of local and distant failure at 5 years were 10% (s.e. = 2%) and 42% (s.e. = 3%), respectively. The late complication rate at 5 years was 25% (s.e. = 2%), comprising mild 16%, moderate 7% and severe 1.3%. The 5 year overall survival rate was 64% (s.e. = 2%) and the cancer-specific survival rate was 74% (s.e. = 3%). Both histological grade and clinical stage were strongly predictive of overall survival and distant failure. Only histological grade was predictive of local failure. Treatment with external beam radiotherapy for this common cancer resulted in survival and disease control rates that compare favourably with other published radiotherapy series and has been accompanied by acceptably low morbidity.  相似文献   
99.
100.
Clinical diagnosis of chronic cholecystitis is made based on diffuse hyperechoic thickening of the gallbladder wall as shown by ultrasonographic examination. We herein report three cases of chronic cholecystitis showing localized hypoechoic thickening of the gallbladder wall that mimicked gallbladder cancer by ultrasonography. Histologically, hypertrophy of the muscularis propria was a common characteristic finding in these three patients. A smooth surface of the inner hypoechoic layer of the thickened wall was considered to be a reliable finding in the differential diagnosis between this type of chronic cholecystitis and gallbladder cancer.  相似文献   
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