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71.
72.
Portsite and intraabdominal metastases of unsuspected gallbladder carcinoma after laparoscopic cholecystectomy: Report of a case 总被引:1,自引:0,他引:1
Nobuhiro Shibata Katsumi Kagotani Sadao Noguchi Masamitsu Tamai 《Surgery today》1996,26(12):1014-1016
We herein report a rare case of portsite metastasis of gallbladder carcinoma which occurred after laparoscopic cholecystectomy. A 64-year-old man underwent laparoscopic cholecystectomy at another hospital for symptomatic cholecystolithiasis. The histological examination revealed an adenocarcinoma of the gallbladder infiltrating the entire wall. Despite the physician's advice the patient refused any additional treatment. Thirteen months after surgery he visited our hospital because of a palpable mass at the scar of the right trocar incision. The nodule was removed and histological examination confirmed metastasis from the gallbladder carcinoma. 相似文献
73.
H. Iwata T. Otoshi N. Takada T. Murai S. Tamano T. Watanabe Y. Katsura S. Fukushima 《Urological research》1995,23(1):27-32
A series of 8 rat and 16 mouse invasive bladder carcinomas were investigated for the presence of silverstained nucleolar organizer regions (AgNORs) to clarify whether this parameter is applicable to the estimation of their invasive character. With regard to number of AgNORs per cell, neither rat nor mouse carcinomas showed any difference between invasive and noninvasive sites within the same tumor. However, the frequency of cancer cells bearing bizarre dots, irregular in size and shape, was significantly higher at sites of actual invasion. Quantitative data generated using an image analyzer revealed significantly lower values for NOR roundness and significantly larger NOR size in invasive sites than in noninvasive sites in all groups. Double staining for the proliferation marker proliferating cell nuclear antigen (PCNA) and AgNORs was performed on eight rat carcinomas and a close correlation between the two was confirmed. Thus the number of AgNORs in PCNA-positive cells was significantly greater than in PCNA-negative cells. Furthermore, a particularly strong correlation was observed for incidences of PCNA-positive cells and bizarre dots (P<0.01). The quantitative data also demonstrated significant differences in size and shape of dots. It is concluded that AgNORs have diagnostic value for the invasive character of bladder carcinomas. 相似文献
74.
本文应用核苷掺入技术及电镜观察首次证实雷公藤内酯对人胃癌细胞株 FGC_(85)的杀伤作用。用药早期,细胞数,分裂指数及 DNA,RNA 合成无明显变化,但出现核仁脱粒及核仁破碎等变化;晚期,电镜观察发现细胞以凋落方式死亡,药物主要作用于间期细胞,其杀伤机构的始动环节可能与核酸代谢障碍无关。 相似文献
75.
Robert Motzer Howard Scher Dean Bajorin Cora Sternberg George J. Bosl 《Investigational new drugs》1990,8(4):391-392
Summary Twenty-three patients with advanced renal cell cancer were treated with Didemnin B. One partial response was achieved (5%) in 21 evaluable patients. An allergic reaction was noted in four patients including one patient with anaphylaxis. Didemnin B is not recommended in the treatment of renal cell carcinoma. 相似文献
76.
A 50 year old man with a two month history of upper abdominal pain and a one month history of anorexia and weight loss, presented
with icterus and evidence of peritonitis. Laparotomy revealed biliary peritonitis which had been caused by a rupture of the
fundus of the gallbladder. The common bile duct was dilated and there was a large growth in the head of the pancreas with
multiple hepatic metastases. A cholecysto-jejunostomy and gastrojejunostomy were done and the patient had an uneventful recovery. 相似文献
77.
We report a rare case of advanced renal cell carcinoma in apatient who showed complete resolution of metastases to thelung and bones after nephrectomy, partial jejunectomy and subsequentalpha-interferon therapy. The patient was a 54-year-old manwhose right lung and left femur metastases were detected beforenephrectomy. In the seventh week after nephrectomy, a partialjejunectomy was carried out because of the obstructive ileuscaused by intraluminal multiple metastases of the jejunum. Apathological fracture of the metastasized right humerus occurredsubsequently. After four months of intramuscular alpha-interferonadministration (3x106 units/day), however, x-rays revealed thecomplete disappearance of the metastatic lung shadow and a solidunion of the humerus, and there were no tumor cells in the femurspecimen resected at the subsequent reconstruction surgery ofthe left leg. Seven years have passed from onset, and the patientis still alive and disease free. 相似文献
78.
Metastatic renal cell carcinoma has occasionally been reported to mimic malignant pleural mesothelioma. Morphologically, histochemically and immunohistochemically, similarities in the two tumours exist making their differentiation difficult, particularly in biopsy specimens. The aim of this study was to make a comparative immunohistochemical analysis of the two tumours by use of a panel of four antibodies (Leu M1; Ber EP4; thrombomodulin and Tamm-Horsfall protein). Their suitability in differentiating between the two tumours was assessed. We examined 20 cases of renal cell carcinoma and 20 cases of malignant pleural mesothelioma. On immunostaining with Leu M1, 14 of 20 renal cell carcinomas were positive, yielding 70% sensitivity and 95% specificity and one of 20 mesotheliomas. In comparison, Ber EP4 antibody stained only seven of 20 of the renal cell carcinomas. In addition, it was noted that four tubulopapillary pattern renal cell carcinomas stained positively with both anti-Leu M1 antibody and Ber EP4 antibody. Thrombomodulin immunostaining was present in 11 of 20 mesotheliomas (55% sensitivity and demonstrated 95% specificity) and one of 20 renal cell carcinomas. For epithelial mesotheliomas only, thromobomodulin staining was identified in 10 of 14 cases. In the differentiation of renal cell carcinoma from epithelial mesothelioma we recommend the use of Leu M1 and thrombomodulin as diagnostically useful markers. None of the antibodies used in this study was effective in distinguishing sarcomatoid renal cell carcinoma from sarcomatous mesothelioma. Tamm-Horsfall protein showed little diagnostic utility in differentiating the two tumours. 相似文献
79.
Hisako Ikeda Jonathan Robbins 《Documenta ophthalmologica. Advances in ophthalmology》1988,69(2):175-186
Anatomical and physiological segregation of neurons into ON (brightening detector) and OFF (darkening detector) channels in the retina and subsequent visual system ensure the high sensitivity required for contrast detection and spatial discrimination. This segregation is finest at the visual axis. Neurochemically, ON and OFF ganglion cells at the visual axis seem to be distinguished by different inhibitory transmitters but not excitatory transmitters. Microiontophoretic studies of inhibitory transmitters on the retinal ganglion cells in kittens and adult cats suggest that this neurochemical distinction is poor in immature ganglion cells at the visual axis. Initially both ON and OFF cells seem to be supplied by GABAergic, glycinergic, and catecholaminergic amacrine cells, but in adults, ON cells remain supplied only by GABAergic amacrines, while OFF cells are supplied by glycinergic amacrines. Postnatal elimination of multiple inputs and strengthening of the appropriate inputs, as seen in the central nervous system, also seem to occur at the retinal neurotransmitter synapses during development. 相似文献
80.
LINDA C PADGETT GE-MING LUI ZENA WERB MATTHEW M LAVAIL 《Experimental eye research》1997,64(6):927-938
Matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) play an essential role in both normal and pathological extracellular matrix degradation, and a TIMP has been associated with at least one type of retinal degeneration. We have studied expression of MMP-2 and TIMP-1 by zymography, immunocytochemistry, and immunoblotting in the retinal pigment epithelium (RPE) from normal, aged and diseased retinas. MMPs and TIMPs were found in the rat RPE, interphotoreceptor matrix (IPM), and in media conditioned by human and rat RPE in culture. In other polarized cells, MMPs and TIMP-2 are secreted vectorially towards the basal lamina. In the RPE, however, MMP-2 and TIMP-1 were secreted preferentially from the apical surface, the surface bordering the IPM. These findings provide new evidence that MMPs and TIMPs could play a role in the turnover of IPM components.Cell homogenates and conditioned media from RPE isolated from mutant Royal College of Surgeons (RCS) rats with inherited retinal dystrophy had similar amounts of MMP-2 and TIMP-1 as those from congenic control rats. The secretion of MMP-2 and TIMP-1 from RPE cell cultures isolated from young and aged human donors varied widely. However, with increasing cell passage number, secretion of MMPs and TIMPs from human RPE increased dramatically. Also, growing human RPE on bovine corneal endothelial cell-generated extracellular matrix instead of plastic reduced the secretion of both MMPs and TIMPs. These data suggest that the integrity of Bruch's membrane may serve to regulate RPE functions in MMP and TIMP secretion and that extracellular matrices contain signals that regulate MMP and TIMP synthesis and/or secretion by the RPE. 相似文献