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71.
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
72.
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
73.
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
74.
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
75.
神经肽Y(NPY)是广泛分布于中枢神经系统和外周神经各部位的神经肽类物质。本实验观察NPY在体外对几种免疫细胞活性的直接作用。结果表明,NPY对小鼠T淋巴细胞丝裂原反应性和NK细胞的杀伤活性均无明显影响(P>0.05),对巨噬细胞分泌溶菌酶有明显抑制作用(P<0.05);而对B淋巴细胞丝裂原反应性则有明显的促进作用(P<0.05)。上述结果提示,NPY对部分免疫细胞功能的影响因细胞种类而异。 相似文献
76.
Aims : Adenocarcinomas account for about 60% of metastatic cancers of unknown primary (CUP) site. In such a clinical CUP situation, histopathologists are challenged to differentiate renal cell carcinomas (RCC) from other adenocarcinomas with similar immunophenotypes, especially chemotherapeutically treatable mammary and ovarian carcinomas. Methods and results : Recently, we produced a monoclonal antibody (mAb), designated 138H11, against human gamma-glutamyltransferase (γGT), which stained over 98% primary clear cell and chromophilic RCC on frozen sections. The 138H11 epitope could not be stained using conventional techniques in most paraffin-embedded sections of the same origin, due to destruction by formalin fixation below the detection level. Here, we demonstrate that mAb 138H11 can specifically stain γGT in paraffin-embedded primary and metastatic RCC after enhancement with an ultrasensitive immunohistochemical method. We analysed a selected subgroup of adenocarcinomas with immunophenotypes which would not allow a differentiation from RCC in a CUP situation. We found a predominantly membranous expression of the 138H11 target antigen in 26/51 primary RCC and 15/34 metastatic RCC. In contrast, all 43/43 primary ovarian and bronchial carcinomas as well as 54/54 metastases of ovarian, mammary, bronchial and gastric carcinomas were negative for mAb 138H11. Conclusions : The data suggest that mAb 138H11 is useful for the immunohistochemical differentiation of RCC from other metastatic adenocarcinomas if the primary site of the tumour is not known. 相似文献
77.
Zusammenfassung
Eine neu aufgetretene Dyspnoesymptomatik und eine symmetrische, apikal betonte retikulonodul?re Zeichnungsvermehrung im R?ntgen-Thorax
bei jungen rauchenden Erwachsenen müssen an das seltene Krankheitsbild der pulmonalen Histiocytosis X denken lassen. Klinischer
Befund, laborchemische- und Lungenfunktionsuntersuchungen zeigen unspezifische Befunde. Neue radiologische Verfahren wie die
hochaufl?sende Computertomographie (HRCT) leisten bei gezielter Indikationsstellung eine entscheidende differentialdiagnostische
Hilfestellung.
Dieser Fall verdeutlicht die M?glichkeit einer Diagnosesicherung durch transbronchiale Biopsien unter Verzicht auf offene
Lungenbiopsien. Eine ambulante Diagnostik war m?glich, das h?here Risiko eines operativen Eingriffes konnte vermieden werden.
Die Indikation zur Therapie ist nicht gesichert und wird daher durch den Grad der subjektiven bzw. funktionellen Einschr?nkung
sowie den Verlauf bestimmt. 相似文献
78.
Macrophages, dendritic cells or B lymphocytes have been shownto play a major role in the presentation of soluble antigensto CD4+ T cells. In contrast, the capacity of these cells topresent particulate antigens such as bacterial or parasiticantigens to T cells remains controversial. To investigate thisquestion, well defined particulate antigens were prepared bycovalent linkage of proteins or peptides to 1 µm in diametersynthetic microspheres. The T cell immunogenicity of such particulateantigens was analyzed in vitro and in vivo. In vitro, a solubleprotein such as hen egg lysozyme (HEL) coupled to beads stimulateda strong proliferative T cell response of lymph node cells fromHEL-primed mice or of specific T cell hybridomas. HEL coupledto beads was presented to the specific T cell hybridomas bysplenocytes or by peritoneal macrophages, but not by lymphomaB cells. Immunization of mice with several different proteinantigens or with a synthetic peptide covalently linked to beadsinduced strong CD4+ T cell responses in the absence of adjuvant.The strong in vivo immunogenicity of proteins coupled to beadsdid not result from a non-specific adjuvant effect of beadssince covalent linkage of the antigen to beads was strictlyrequired to induce T cell responses in the absence of adjuvant.In vivo treatment by carrageenan showed that macrophages arerequired for the in vivo stimulation of T cell responses bythese particulate antigens. Thus, these results demonstratedthe role of phagocytic cells, especially macrophages, for invivo presentation of particulate antigens. These particulateantigens represent an interesting approach for the developmentof new vaccines, and for the in vivo analysis of the role ofvarious antigen presenting cells in T cell activation and differentiation. 相似文献
79.
The cellular and regional distribution of glutathione (GSH) and GSH-related enzyme systems involved in cellular defense against reactive oxygen species and electrophilic xenobiotics in the nervous system has been extensively studied. However, little is known about the subcellular distribution of GSH systems in brain tissue and cultured neural cells. The present study investigates the distribution of mitochondrial and cytosolic GSH and GSH-related enzymes in cultured cerebellar astrocytes and granule cells, and compares them with levels in the adult rat cerebellum. Cytosolic GSH levels and cytosolic activities of glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) in astrocytes were 57, 153, 245, and 92% higher than those found in granule cells, respectively. In contrast, granule cells contained significantly higher mitochondrial GSH levels than astrocytes. Granule cells also demonstrated comparable mitochondria/cytosolic concentrations of GSH and GR, GPX and GST activities to those observed in the cerebellar tissue, whereas ratios in astrocytes were markedly lower. Although in vitro treatments with 100 μM ethacrynic acid depleted both cytosolic and mitochondrial GSH in cultured astrocytes and granule cells in a time-dependent fashion, cellular GSH in granule cells was more resistant to the GSH-depleting agent than astrocytes. These results suggest that although GSH and GSH-related enzymes are abundant in cytosolic compartments of astrocytes, mitochondrial pools are relatively small. Since brain mitochondria are sites of significant hydrogen peroxide generation, the mitochondrial localization of GSH and its associated enzymes in neural cells provide important defenses against toxic oxygen species in the nervous system. Differences in subcellular distribution of GSH systems in individual neural cell types may provide a basis for selective cellular and/or subcellular expression of neurotoxicity. 相似文献
80.
用小鼠胎肝细胞体外血浆凝块培养红系集落(Erythroid colong formig unit inculturc,E-CFUc)方法,以红细胞生成素(Erythropoietin,EPO)850323为标准试剂,测定正常人、贫血病人血清EPO浓度。实验用妊娠13~15d小鼠胎肝细胞。血清均经透析处理,培养液中加量最大不超过10%。EPO(850323)在培养液中浓度为2.5~100mU/ml。血清EPO(mU/ml)测定结果:28例正常人为48.O±17.7,12例再生障碍性贫血病人为946~>10000,1例巨幼细胞性贫血病人为500,1例缺铁性贫血病人为400和18例慢性肾功能衰竭病人则为94.2±87.6。结果表明:贫血病因对血清EPO浓度有影响。 相似文献