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81.
BACKGROUND: Total excision of colonic polyps is not always attainable and in some patients it is clinically contraindicated. Also, a resected polyp may be lost at any step between its endoscopic removal and its embedding in paraffin. The aim of this study was to compare the histological features of colonic polyps as analysed by the study of biopsy-forceps obtained samples with those assessed on scrutinizing the totally resected growths. PATIENTS AND METHODS: This prospective study included a cohort of 59 patients in whom, in the course of an elective colonoscopy, a total excision of a 6 mm-sized or larger polyp was called for. Sizeable biopsies were obtained by means of an Olympus Multibyte forceps prior to the total polypectomy. Subsequent to the study of the polypectomy specimens, the forceps biopsy samples were submitted for histological examination. The pathologists were blinded as to the source of the tissue they were studying. The diagnoses rendered by evaluating the biopsy samples and polypectomy specimens of each patient were contrasted with each other. RESULTS: Major discrepancies between the histological features of the fragments captured by the biopsy-forceps and the factual nature of the totally removed polyps were uncovered in 11 (18.6%) of 59 cases. Intriguingly, the grade of the tumours was underrated in all the 11 cases, as judged by contrasting the tentative diagnoses of the forceps-biopsies with the decisive diagnoses of the polypectomies. Importantly, 2 adenocarcinomas would have been missed by just looking at the forceps-retrieved sample. CONCLUSIONS: In our experience, a discordance of 18.6% is to be expected between the diagnoses rendered after examining forceps-biopsies of and totally excised colonic polyps. Nevertheless, it is advisable to procure biopsies prior to the excision of the growths, because on those occasions in which patients' growths cannot be removed or have not been retrieved for one reason or another, a small forceps-captured tissue sample correctly reflects the characteristics of the polyp in 81.4% of the cases. Finally, the biopsies may be discarded in the event that total removal was successful.  相似文献   
82.
神经内镜治疗脑室内病变   总被引:7,自引:2,他引:5  
目的探讨脑室内病变的神经内镜治疗。方法应用神经内镜对68例脑室内病变进行治疗,其中松果体区肿瘤16例,囊性颅咽管瘤15例,丘脑肿瘤14例,脑室内囊肿16例,侵及室管膜下的胼胝体肿瘤3例,侧脑室脉络丛乳头状瘤2例,侧脑室猪囊尾蚴病1例,侧脑室内分流管脱落1例。结果随访17~69个月,56例有效,12例死于肿瘤扩散。无严重并发症。结论对脑室内病变选择性应用神经内镜治疗安全、有效。  相似文献   
83.
BACKGROUND: Insulin-like growth factor binding protein-2 (IGFBP-2) is expressed by all human prostate cancer cell lines and dramatically increases in the serum of prostate cancer patients. However, the role of IGFBP-2 in prostatic tumorigenesis is not known. The aim of the present study was to investigate the effects of IGFBP-2 on the proliferation of DU145 human prostate cancer cells in culture. METHODS: Using cell proliferation assays, we examined the effects of exogenously administered and endogenously modulated levels of IGFBP-2 on the proliferation of DU145 cells. RESULT: Cell growth was stimulated by exogenously administered IGFBP-2, but significantly retarded (P < 0.05) by its neutralizing antibody. Overexpression of IGFBP-2 by transfection also stimulated cell growth, which was significantly (P < 0.05) inhibited in transfectants expressing antisense mRNA to IGFBP-2. Furthermore, the proliferation of IGFBP-2 overexpressing cells was significantly dampened by exogenously administered IGFBP-2 antibody. CONCLUSIONS: IGFBP-2 is an autocrine growth factor for DU145 human prostate cancer cells and cell proliferation can be significantly retarded by neutralizing or inhibiting its synthesis. These findings provide a strong rationale for targeting IGFBP-2 in the testing of novel strategies to treat prostate cancer.  相似文献   
84.
BACKGROUND: We retrospectively compared the 5-year survival rates of T1b-T3N0M0 prostate cancer patients treated either by endocrine therapy plus radical prostatectomy or endocrine therapy alone. METHODS: Clinical T1b-T3N0M0 prostate cancer patients were enrolled at 104 institutions in Japan. They were assigned to study 1 (n = 176), if they were indicated to prostatectomy, if not indicated, they were assigned to study 2 (n = 151). The indication of prostatectomy was based on the clinical judgement of physicians and/or patients. Those assigned to study 1 underwent prostatectomy and adjuvant endocrine therapy with or without preoperative androgen deprivation. Those assigned to study 2 were treated with leuprorelin acetate with or without chlormadinone acetate. They were followed-up every 3 months until death or for 5 years and over. RESULTS: Those assigned to study 1 were younger (mean age 67.2 vs 75.7 years), less advanced in clinical stage, and had lower prostate specific antigen levels (mean 43.8 vs 103.6 ng/mL). Death for any reason was observed less frequently in study 1 (n = 29, 16%) than study 2 (n = 50, 33%), and the 5-year overall survival rate was higher in study 1 (87 vs. 68%). However, prostate cancer deaths were comparatively seldom (9% in study 1 and 7% in study 2), resulting in the identical 5-year cause specific survival rate in both study groups (91%). In both study groups the overall survival was almost equal to the natural survival of age-matched men. CONCLUSIONS: Endocrine therapy offers a reasonable survival rate in T1b-T3 prostate cancer patients within a 5-year follow-up. Observation will be extended to determine 10-year outcomes.  相似文献   
85.
SA、F/TPSA及PSAD在前列腺癌诊断中的作用   总被引:1,自引:0,他引:1  
目的 :探讨血清前列腺特异抗原 (PSA) ,血清总PSA及游离PSA比值 (F/TPSA)及前列腺特异性抗原密度(PSAD)在前列腺癌诊断中的作用。方法 :对 5 1例前列腺癌患者及 14 5例良性前列腺增生症患者PSA、F/TPSA及PSAD值的差异进行分析、比较。结果 :前列腺癌组血清PSA及PSAD高于良性前列腺增生组 ;而F/TPSA值低于良性前列腺增生组 ,差异均有显著性。结论 :PSA >4ng·ml-1作为筛选前列腺癌的临界值存在一定缺陷 ;当PSA <10ng·ml-1,F/T值有助于鉴别前列腺癌和良性前列腺增生 ;而PSAD对于筛选前列腺活检病例亦有一定价值。  相似文献   
86.
关木通引起慢性间质性肾炎7例报告   总被引:3,自引:0,他引:3  
目的 观察关木通所致慢性肾损伤的临床和病理改变特点。方法 本组 7例中 ,男 5例 ,女 2例。 3例服关木通汤药 ,4例服含关木通成药。分析服用时间、累积总量与肾损害首发症状及症状出现时间、肾功能和肾病理改变的关系。结果 汤药组 :服药时间平均 3 3 3个月 ,累积总量平均 82 9 3 g ,首发症状为乏力 3例 ,夜尿增多 2例 ,平均时间为 8 3个月 ,Cr平均 40 2 μmol/L。肾病理 :3例均为重度寡细胞性肾间质纤维化 ,肾小管广泛萎缩。成药组 :服药时间平均 7 5个月 ,累积总量平均 13 6g ,乏力 3例 ,夜尿增多 1例 ,恶心呕吐、头痛头晕 1例 ,平均18 8个月 ,Cr 3 62 8μmol/L。肾病理为重度寡细胞性间质纤维化和灶状纤维化各 2例 ,肾小管灶状萎缩 3例 ,广泛萎缩 1例。结论 汤药组关木通积累大 ,发病时间早 ,肾病理改变重。提示关木通所致肾损其临床表现、病理改变与服用关木通时间、剂量相关。  相似文献   
87.
The determination of penetration pathways of topically applied substances into the skin is the subject of several investigations. Recently, follicular penetration has become a major focus of interest. To date, a direct, non-invasive quantification of the amount of topically applied substance penetrated into the follicles had not been possible. The development of such a method was the aim of this study. Therefore, the advantages of both stripping techniques, tape stripping and cyanoacrylate skin surface biopsy, were combined and evaluated. Tape stripping was used to remove the part of the stratum corneum that contained the topically applied dye. Subsequently, the follicular contents were ripped off by cyanoacrylate skin surface biopsy. The combined method termed "differential stripping" was evaluated in vitro and in vivo , and the amount of topically applied fluorescent dye penetrated into the hair follicles was quantified after different penetration times. After 30 min, 5% of the recovered concentration of sodium fluorescein was found in the follicular infundibula, where it was still detectable after 48 h. Altogether, the results of this investigation revealed that differential stripping is a new method that can be used to study the penetration of topically applied substances into the follicular infundibula non-invasively and selectively.  相似文献   
88.
The aim of this study was to examine the effect of purple coneflower (Echinacea purpurea L. Moench) on the prostate gland of rats using an experimental model of benign prostate hyperplasia (BPH). The animals were administered 50 mg/kg of extract preparation for 4 and 8 weeks and the prostate mass and structural degenerative changes were evaluated in the course of the experiment. The administration of E. purpurea extract to rats with hyperplasia for 4 and 8 weeks gradually and significantly reduced the prostate mass and reversed the degenerative changes in the structure of the prostate gland. The present investigation suggests extract of purple coneflower prevents the development of BPH. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
89.
目的探讨经尿道等离子双极电切治疗前列腺增生症(PKRP)的安全性和疗效。方法回顾分析经尿道等离子双极电切治疗前列腺增生112例,比较术前术后尿流率,前列腺症状评分,残余尿量;记录手术失血量,体重变化,切除前列腺组织重量。结果所有手术顺利完成,切除前列腺重量65±15.5g,手术时间40±7.5min,平均出血量150ml,最大尿流率(Qmax)术前7.4±2.6ml/s术后3个月为18.6±4.6ml/s;国际前列腺症状评分(IPSS)术前生活质量评分22.6分,术后3个月为6.5;残余尿量(RUV)术前>60m1,术后<20ml。结论等离子双极电切治疗前列腺增生症具有安全,有效,经济,技术易于掌握等优点,适合基层医院开展。  相似文献   
90.
Antiandrogen withdrawal syndrome (AWS) is a well-established phenomenon in prostate cancer. However, responses to AWS are usually of limited duration, and a complete response (CR) is extremely rare. We present two patients who exhibited a chemical CR for more than 2 years after the discontinuation of steroidal antiandrogen chlormadinone acetate use. Whether patients who respond to antiandrogen withdrawal include a group of patients with a better prognosis remains uncertain. However, considering that the usual survival period of patients with hormone-resistant prostate cancer is approximately 12 months, both of the patients reported here, who are present in excellent physical condition, exhibiting an improved quality of life, and attending their hospital as outpatients, obviously acquired a prolonged survival because of AWS.  相似文献   
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