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41.
BACKGROUND: Although it is clear that dissemination via the blood system involves angiogenesis, it is uncertain whether tumors also induce lymphangiogenesis or simply invade existing peritumoral vessels. The purpose of this study was to elucidate changes in tumor blood and lymph vessels in cases involving the invasion of squamous cell carcinoma in the oral cavity, and its significance. Blood and lymph vessels densities in tongue carcinomas induced in hamsters were investigated. METHODS: Tongue cancer was induced by abrading the right margin of the tongue of each hamster with an endodontic barbed broach and subsequently applying 1.0% 9,10-dimenthl-1,2-benzanthracene (DMBA) dissolved in acetone, three times a week, at the same site. Fresh frozen sections were prepared and blood vessels stained blue by perfusion with Coomassie Brilliant Blue and lymph vessels stained brown for 5'-nucleotidase. The effects on the blood vessels and lymph vessels were observed. RESULTS: The results showed that blood and lymph vessel densities were greater in the advanced carcinoma tissues than in normal tissue. These were compared in terms of the mode of cancer invasion. As tumor invasion progressed, the blood vessel density decreased but lymph vessel density tended to be higher in high-degree tumor invasion than in low-degree tumor invasion. The expression of vascular endothelial growth factor-C was seen more frequently as tumor invasion progressed. CONCLUSIONS: The present findings indicated that angiogenesis and lymphangiogenesis are affected by cancerous invasion.  相似文献   
42.
The aim of this study is to assess accuracy of transvaginal ultrasound (TVUS) and diagnostic hysteroscopy in diagnosing endometrial polyps and to determine premalignancy and malignancy rates in asymptomatic women. The study was designed to retrospectively analyze 438 women who underwent operative hysteroscopy in a day-care unit when endometrial polyp was suspected after TVUS and diagnostic hysteroscopy. Multivariate logistic regression modeling showed effects of age, previous breast cancer with tamoxifen treatment, and menopause with or without bleeding on pathologic results. The results indicate that positive predictive value of TVUS with diagnostic hysteroscopy was 79.9%. Premalignancy or malignancy occurred in 3.2% and was significantly related to menopause with abnormal bleeding (P < 0.001), which carried a 20-fold higher risk of pathology than any other group. Age was also a risk factor. It was concluded that TVUS with diagnostic hysteroscopy reliably evaluates endometrial polyps. The low incidence of endometrial tumors in asymptomatic (especially premenopausal) women suggests that their operative evaluation may not be cost effective. Larger studies are needed to support this tentative conclusion.  相似文献   
43.
目的探讨缺氧条件对卵巢癌细胞Caov-3体外黏附和迁移能力的影响。方法在常氧和缺氧条件下培养卵巢癌细胞Caov-3,分别用四甲基偶氮唑蓝(MTT)比色法和细胞迁移试验测定常氧和缺氧条件下培养的Caov-3细胞体外黏附和迁移能力。结果缺氧条件下,Caov-3细胞在Matrigel和纤维连接蛋白Fn基质上黏附数量增加,黏附促进率分别为17.1%和15.2%,与常氧条件下比较有显著性差异(P<0.05)。缺氧条件下,Caov-3细胞在Matrigel基质上迁移距离增大,分别为258.8±19.5μm和331.3±24.4μm,迁移促进率为28.0%,与常氧条件下比较有显著性差异(P<0.05)。结论缺氧环境对卵巢癌细胞Caov-3体外黏附和迁移具有明显的促进作用。  相似文献   
44.
A 69‐year‐old man was admitted to Toho University Omori Medical Center complaining of icterus. Abdominal computed tomography, magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography were suspicious of cholangioma of inferior bile duct. Peroral cholangioscopy using narrow band imaging (NBI) was performed and it was possible to diagnose the mucosal spread lesions of cholangioma. Histological findings reflected the endoscopic findings. Mucosal spread lesions of cholangiocarcinoma were successfully diagnosed using the CHF‐B260 for NBI.  相似文献   
45.
Renal cell carcinoma (RCC) causes many kinds of symptoms such as hypercalcemia, hypertension, polycythemia and fever. Here we describe a rare case of RCC presenting with a persistent cough. After radical nephrectomy, the obstinate cough disappeared. When the tumor recurred locally, the cough also recurred. Furthermore, the cough disappeared completely again after the removal of the recurrent tumor. Although all the clinical findings suggested that the RCC caused the cough, we could not identify a specific humoral substance responsible for the cough.  相似文献   
46.
Since 1998, we have performed minimum incision endoscopic surgery (MIES) for renal cell carcinoma (RCC). For seven dialysis patients with bilateral RCC, we have performed sequential bilateral MIES radical nephrectomy. It was carried out by retroperitoneal approach through a single minimum incision that narrowly permitted extraction of the specimen using endoscopy and direct stereovision, without trocar ports, without gas insufflation and without the insertion of the hands of operators into the operative field. Although six of the seven patients had multiple complications in addition to chronic renal failure (CRF), bilateral kidneys were successfully removed by sequential MIES radical nephrectomy without major operative complication. Postoperative recovery was prompt with all patients resuming oral feeding and walking by the second postoperative day. Sequential bilateral MIES radical nephrectomy, leaving the peritoneal cavity intact and without imposing circulatory stress caused by gas insufflation, is a feasible treatment for bilateral RCCs in dialysis patients.  相似文献   
47.
目的分析和总结残胃癌的外科诊断、治疗及预后情况。方法对1990年以来收治的35例残胃癌的发病率、临床表现、治疗情况和预后进行回顾性分析。结果首次胃切除以胃溃疡为主,占65.7%,首次手术BillrothⅡ式占82.9%(29/35)。残胃癌早期缺乏特异的症状,主要为上腹部隐痛不适,首次手术距临床诊断残胃癌的间隔时间平均为16.3年。本组残胃癌手术切除率及根治性切除率分别为77.1%和54.3%,根治性切除患者1、3、5年生存率分为78.9%、52.6%、36.8%,Ⅰ期、Ⅱ期患者的5年生存率为72.7%。结论胃良性病行手术治疗时以BillrothⅠ式为首选,定期胃镜检查是早期诊断残胃癌的关键,根治性切除是治疗残胃癌的有效方法及影响残胃癌预后的重要因素。  相似文献   
48.
The rising incidence of hepatocellular carcinoma (HCC) in western countries, along with the poor prognosis offered by present-day treatment modalities, makes novel therapies for this disease necessary. Oncolytic herpes simplex viruses (HSV) are replication-competent viruses that are highly effective in the treatment of a wide variety of experimental models of human malignancies. This study seeks to investigate the effectiveness of oncolytic herpes viruses in the treatment of primary HCC cell lines. Sixteen commercially available human HCC cell lines were studied. G207 is an attenuated, replication-competent, oncolytic HSV engineered to selectively replicate within cancer cells. Cell lines were tested for viral sensitivity to G207 and their ability to support viral replication using standard cytotoxicity and viral replication assays. Eleven of 16 cell lines were moderately to highly sensitive to G207 viral oncolysis. HCC cell lines additionally demonstrated the ability to support viral replication in vitro with as high as 800-fold amplification of the administered viral dose observed. G207 is cytotoxic to, and efficiently replicates within, HCC cell lines in vitro. From these data, we suggest that oncolytic HSV therapy may have a role in the treatment of HCC, and in vivo studies are warranted. Presented in part at the 2005 American Hepato-Pancreato-Biliary Association Congress, Hollywood, Florida, April 14–17, 2005. Supported by grants R01CA75461 and R01CA72632 from the National Institutes of Health, and by grant MBC-99366 from the American Cancer Society (Yuman Fong).  相似文献   
49.
Aim: To investigate the clinico‐pathological profile and stage of disease at presentation of patients with carcinoma of the gallbladder diagnosed during 1992–2006 in Iran. Methods: During this study period 34 consecutive patients with gallbladder carcinoma were identified using a pathology‐based tumor database. The data extracted for each study patient included their gender, age at diagnosis, signs and symptoms, presence of gallstones and histopathological pattern of the gallbladder carcinoma and the UICC/AJCC TNM staging system was used for labeling the stages of the disease. Results: The median age of the 34 patients studied was 69.50 with most between 61 and 70 years of age. The age range of the men was between 53 and 80 years with a median age of 71.50 years and that of the women was between 33 and 79 years with a median age of 68.50 years. The most common symptom was pain in the right hypochondrium. More women had gallstones (15/34) than men (3/10). Adenocarcinoma was the most common histopathological type (91.18%) with the commonest subtype being papillary (47.06%). Eighteen patients had stage IB and stage IIA (52.94%) carcinomas whereas stages IIB and III were observed in six (17.6%) and seven cases (20.6%), respectively. Only three cases (8.82%) were seen in stage IV. The follow up of gall bladder carcinoma (GBC) patients in this study ranged from 6 to 60 months. However, there was a progressive reduction of patients attending follow‐up oncology clinic, particularly by those who had stages III and IV of the disease. Conclusion: Most patients (52.94%) presented with early disease (stage IB and IIA) which carries a good prognosis. Early detection of GBC and a national consensus for the evidence‐based management of GBC in Iran should be the major components of a strategy aimed at improving therapeutic outcome.  相似文献   
50.
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