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41.
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   
42.
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   
43.
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   
44.
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   
45.
Masujiro Makita  MD  Futoshi Akiyama  MD    Naoya Gomi  MD    Takuji Iwase  MD  Fujio Kasumi  MD  Goi Sakamoto  MD 《The breast journal》2006,12(S2):S210-S217
Abstract:   To improve the utility of mammary ductoscopy, we investigated the correlation between endoscopic findings and histologic findings using intraductal biopsy specimens. Seventy-one intraductal biopsy specimens obtained from 63 patients between October 2001 and March 2004 were analyzed retrospectively. All specimens were obtained from monotonous intraductal lesions immediately after observation by mammary ductoscopy and were composed of a pure histologic subtype. With regard to endoscopic findings, color was classified as yellow, red, white, or colorless, and morphology was classified as spherical, lobular, mulberry, or amorphous. The histologic subtype was classified as papillotubular, papillary, degenerated, papillary cancer, solid-type ductal carcinoma in situ (DCIS), or cribriform cancer. The relationship between histologic diagnosis, color, and morphology was investigated. Intraductal biopsy specimens included 25 specimens of carcinoma and 46 specimens of papilloma. There was no significant correlation between color and diagnosis. Fourteen of 25 carcinoma specimens were amorphous, and amorphous morphology was significantly suggestive of malignancy (p < 0.001). Further, cribriform cancer was associated with amorphous morphology and yellow color. Morphology may be a useful endoscopically delineated parameter for differentiating intraductal lesions.   相似文献   
46.
47.
Management of an indeterminate pulmonary nodule is a diagnostic challenge that commonly confronts primary care physicians and specialists. Patients often present with this radiographic finding in the course of an unrelated medical evaluation. We examined our institution's experience with percutaneous biopsy of lung nodules to determine the impact of this procedure on overall patient care. Although significant complications are uncommon, the expedience of percutaneous lung biopsy often supplants a surgical opinion prior to initiation of therapy without added diagnostic benefit or cost-savings. Hence, we caution practitioners to use this technique as an adjunct to diagnosis and not a substitute for multidisciplinary care.  相似文献   
48.
观察保肾口服液对IgA肾病小鼠T细胞^3H-TdR掺入及其分泌IL-2水平的影响,结果表明低、中、高3种浓度的保肾口服液均能显著促进IgA肾病小鼠的自发性和ConA刺激的T细胞^3H-TdR掺入,促进T细胞合成,分泌IL-2,提前给药作用相同。提示保肾口服液有显著增强IgA肾病小鼠细胞免疫功能的作用。  相似文献   
49.
星形细胞瘤瘤周水肿区立体定向活检组织的超微结构研究   总被引:1,自引:0,他引:1  
目的探讨星形细胞瘤瘤周脑水肿的发生机制。方法对15例星形细胞瘤瘤周脑水肿的宽度进行分级:一级0~20mm、二级21~40mm、三级〉40mm。结合CT平扫及增强扫描的影像,应用立体定向技术,对15例星形细胞瘤瘤体、瘤周水肿区及正常脑组织的活检标本进行电镜观察比较。结果CT增强扫描可强化,瘤周脑水肿明显的病人,其瘤体及瘤周水肿区毛细血管超微结构均有不同程度的改变。毛细血管的分布和结构变化,影响着瘤周水肿区的形态,瘤体毛细血管的明显异常,出现于大范围瘤周水肿区的病例。CT增强扫描无强化,瘤周脑水肿不明显的病人,毛细血管超微结构与正常脑组织相似。结论伴有明显瘤周脑水肿的星形细胞瘤,其瘤体及瘤周水肿区毛细血管超微结构均有不同程度的改变,而瘤周水肿的产生,是瘤体及瘤周水肿区毛细血管超微结构改变共同作用的结果。  相似文献   
50.
The data concerning the value of duplex sonography in diagnosingparenchymatous renal allograft dysfunction are controversial.Most early studies did not take into consideration the manyfactors influencing resistance parameters. We therefore performeda prospective, biopsy-controlled study with exclusion of allknown sources of error regarding resistance parameters. Furthermorewe investigated the value of a new resistance parameter, thesystolic deceleration percentage. Forty-seven duplex sonographicstudies were performed on 43 patients (30 male, 13 female, medianage 47 years, range 7–70). Fourteen studies were doneon normally functioning grafts (control group) an average of33 days after transplantation. Thirty-three studies were performedon dysfunctional grafts immediately prior to biopsy. Graftswhich had been transplanted more than a year previously or withvascular findings or any other clinical or sonographic pathologyprobably explaining function deterioration were excluded. Inall patients, the resistive index (RI), pulsatility index (PI)and systolic deceleration percentage (DP) were calculated inthe main renal artery and in the interlobar artery. Of the 33grafts with dysfunction, nine had vascular rejection (VR), 11interstitial rejection (IR), 11 cyclosporin A toxicity (CAT)and two other histologies (OR). The mean RI in normal grafts(NO) was 0.71±0.06 in the main artery and 0.68±0.06in the interlobar artery, in VR 0.86±0.12 and 0.80±0.18,in IR 0.72±0.05 and 0.70±0.07, in CAT 0.67±0.06and 0.65±0.07 and in OR 0.64±0.07 and 0.60±0.01.For PI, the values were 1.45±0.23 and 1.41±0.28(NO), 3.5±2.13 and 2.92±2.16 (VR), 1.55±0.26and 1.46±0.33 (IR), 1.32±0.25 and 1.27±0.26(CAT) and 1.30±0.34 and 1.13±0.04 (OR). For DPwe calculated 28±5% and 29±6% (NO), 43±14%and 36±6% (VR), 29±9% and 27±9% (IR), 31±8%and 32±7% (CAT ) and 32±4% and 28±3% (OR).The sensitivity/specificity for VR with a cutoff mean+2 SD was0.44/1 for RI, 0.55/0.97 for PI and 0.33/0.89 for DP. It wasconcluded that:(1) despite the high selection of our patientgroup, diagnostic accuracy of duplex sonography for diagnosingparenchymatous function disorder in renal allograft remainsinsufficient; (2) in vascular rejection only, the resistanceparameters differ significantly from the values of normal allografts;(3) the higher the cutoff of resistance parameters, the betterthe specificity and the worse the sensitivity for diagnosingvascular rejection; (4) of all investigated resistance parameters,the RI is the most practical due to a simple measurement technique.  相似文献   
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