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81.
Hepatitis B surface antigen (HBsAg) has been reported to be present in other organs than the liver.3,9 So far as our knowledge is concerned, however, any report of cases dealing with pancreatic diseases induced by hepatitis B virus (HBV) has not been described in the English and Japanese literature. We report an autopsy case with a pancreatic lesion characterized by damage of both exocrine and endocrine epithelial cells with inflammatory response, which were immunohistochemically found to be positive for HBsAg, and electron-microscopically to possess core-like particles In the nucleus and cytoplasm.  相似文献   
82.
83.
A case of Hodgkln's disease (HD), lymphocyte depression (LD) type In an Immunosuppressive patient is described. The patient was a 48-year-old male and his parents were born In the Kyushu area, which is an endemic area for adult T cell lymphomaheukemla (ATL). He was seropositive for ATL virus (ATLV, also referred to as HTLV-I) and showed a marked Immunosuppressive condition. He developed LD-HD and Pneumocystis carinii pneumonia, and died due to respiratory failure. The Immunohistochemical and in situ hybridization analyses revealed that the Reed-Sternberglike cells In the lymph node biopsy sample were positive for Ber-H2 (CD30), Leu-M1 (CD15), L-26 (CD20), Bcl-2, p53 and EBER, the viral genome of Epstein-Barr virus (EBV).  相似文献   
84.
Three cases of peripheral small cell lung carcinoma (SCLC) with central fibrosis are presented. Central fibrosis is usually present in adenocarcinomas. Cases 1 and 2 are combined SCLCs with components of papillary adenocar-cinoma, and case 3 is a mixed SCLC with a large cell component. Small cell Components showed intermediate cell type in ail cases. In cases 1 and 2, there was a gradual transition between small cell carcinoma and papillary ade-nocarcinoma. Small cell components showed Grimelius argyrophilia, but other neuroendocrine markers such as neuronspecific enorase, chromogranin A, Leu-7 and syn-aptophysln were negative. The chest X-ray examination of case 1 demonstrated rapid enlargement of a tumor shadow, which was present two years before, for a recent year. Central fibrosis, coexistence of small cell carcinoma and papillary adenocarcinoma, and a change of growth rate in the chest x-ray may suggest that some SCLC derive from papillary adenocarcinomas.  相似文献   
85.
The effect of noradrenaline (NE) on rat islet -cells was examined. NE reduced insulin secretion from rat islets exposed to extracellular solutions containing glucose at 5.5 or 16.6 mM. In islets treated with pertussis toxin (PTX), however, NE increased insulin secretion. The NE-induced augmentation of insulin secretion was inhibited by prazosin. In intact islets, NE increased phospholipase C (PLC) activity, an effect that was prevented by treatment of islets with U-73122. NE elevated intracellular [Ca2+] ([Ca2+]i) in isolated -cells independently of PTX. Although this NE effect was inhibited by prazosin, phenylephrine did not mimic it. The [Ca2+]i response to NE was also prevented by the treatment of cells with U-73122. NE produced depolarization of -cells followed by nifedipine-sensitive action potentials. NE reduced the whole-cell membrane currents through ATP-sensitive K+ channels (KATP), responsible for the depolarization. This NE effect was prevented by treatment of -cells with U-73122 or BAPTA/AM. Although at least some of our results imply the presence of 1-adrenoceptors, -cells were not stained by a polyclonal IgG antibody recognizing all adrenergic 1-receptor subtypes so far identified. These results suggest that an interaction of NE with an unknown type of receptor activates rat islet -cells via a PLC-dependent signal pathway. This effect is, however, masked by the inhibitory action via a PTX-sensitive pathway also activated by NE.  相似文献   
86.
We compared morphological and morphometric data on various motor neurons in the human pyramidal system using the modified Klüver-Barrera staining method with extremely minimized shrinkage ratio and an image-analyzer. We classified motor neurons in the human pyramidal system into three groups according to the measurement data. This report may be of interest to better understand the process of nerve conduction in the human pyramidal system.  相似文献   
87.
The laminar distribution and morphological features of parvalbumin-immunoreactive [PV(+l)] neurons, one of the subpopulations of GABAergic neurons, were studied in the rat olfactory bulb at a light microscopic level. In the main olfactory bulb of adult rats, PV(+) neurons were mainly located in the external plexiform layer (EPL), and a few were scattered in the glomerular layer (GL), mitral cell layer (ML), and granule cell layer (GRL); whereas PV(+) neurons were rarely seen in the accessory olfactory bulb. The inner and outer sublayers of the EPL (ISL and OSL) appeared to be somewhat different in the distribution of PV(+) somata and features of PV(+) processes. PV(+) somata were located throughout the OSL, and PV(+) processes intermingled with one another, making a dense meshwork in the OSL; whereas, in the ISL, PV(+) somata were mainly located near the inner border of the EPL, and PV(+) processes made a sparser meshwork than that in the OSL. PV(+) neurons in the EPL were apparently heterogeneous in their structural features and appeared to be classifiable into several groups. Among them there appeared five distinctive types of PV(+) neurons. The most prominent group of PV(+) neurons in the OSL were superficial short-axon cells, located in the superficial portion of this sublayer and giving rise to relatively thick processes, in horizontal or oblique directions, which usually bore spines and varicosities. Another prominent group of PV(+) neurons extended several short, branched dendrites with spines and varicosities, which appeared to intermingle with one another, making a relatively small, spherical or ovoid dendritic field around the cell bodies; most of them resembled Van Gehuchten cells reported in previous Golgi studies. A third distinctive and most numerous group of PV(+) neurons were of the multipolar type; their somata and processes were located throughout the EPL. Their relatively smooth processes with frequent varicosities and a few spines were extended horizontally or diagonally throughout the EPL. A fourth group, which could be a subtype of the multipolar type, were located in or just above th ML and extended several thin, smooth dendrites in the EPL, some of which appeared to reach the border between the GL and EPL. Occasionally, axonlike processes arose from their cell bodies and extended into the ML. This fourth type of PV(+) neuron was named inner short-axon cells. A fifth group of neuron was located in the ML; processes of these neurons were extended horizontally, so they were named inner horizontal cells. PV(+) processes from the fourth and the fifth group of cells appeared to make contacts on mitral cell somata. In the GL some presumably periglomerular cells were also PV(+). In the GRL, PV(+) neurons were small in number, but they were also heterogeneous in their structural features; Some were identified as Golgi cells. This study shows a tremendous heterogeneity in morphological features of a chemically defined subpopulation of GABAergic interneurons in the olfactory bulb.  相似文献   
88.
Fibronectin with IIICS region is present in rheumatoid synovium, and fibronectin fragments are increased in rheumatoid joints. We investigated the ability of COOH-terminal heparin-binding fibronectin fragment (COOH-HBFN-f) containing IIICS to induce matrix metalloproteinase (MMP) production and the role of mitogen-activated protein kinase (MAPK) pathway and CS-1 sequence that can bind alpha4beta1 integrin in MMP induction by COOH-HBFN-f in rheumatoid synovial fibroblasts (RSF). When RSF in monolayer culture were incubated with COOH-HBFN-f, COOH-HBFN-f stimulated the production of MMP-1, MMP-3, and MMP-13 by RSF in association with activation of extracellular signal-regulated kinase, p38 MAPK, and c-Jun NH(2)-terminal kinase. Immunoprecipitation of cell lysates demonstrated the presence of alpha4 integrin in cultured RSF. Similar to COOH-HBFN-f, treatment with CS-1 synthetic peptide derived from IIICS resulted in increased MMP production and activation of the kinases, although the MMP levels were low. Preincubation of RSF with anti-alpha4 integrin antibody resulted in partial suppression of the COOH-HBFN-f-stimulated MMP production. Inhibition studies using protein kinase inhibitors (PD98059 and SB203580) showed that those MAPK pathways contributed to MMP up-regulation by COOH-HBFN-f and CS-1. Thus, the present results have clearly shown that COOH-HBFN-f and CS-1 stimulate MMP production in association with activation of MAPK pathways in RSF. Integrin alpha4beta1 may be partially involved in the MMP induction by COOH-HBFN-f.  相似文献   
89.
BACKGROUND/AIM: Although OAS (oral allergy syndrome) during childhood is believed to be rare, it seems to be increasing these days. METHODS, SUBJECTS: We here report 16 cases of childhood OAS, which were diagnosed, in our division. In addition to these reports, we investigated the rate of sensitization against four major pollens (Japanese cedar, orchard grass, short ragweed, alder) among 1067 pediatric patients with allergic diseases (median age: 4 years old) in our division. The sensitization was examined by IgE CAPRAST and above class 2 was judged as positive sensitization. RESULTS: OAS in childhood differs from that in adulthood in some ways. One is that childhood OAS does not always accompany with pollinosis. The most frequent allergen in our study was kiwi fruits followed by tomato, orange and melon among these patients. The sensitization rate against alder was equivalent as that against orchard grass and short ragweed, but less than that against Japanese cedar. CONCLUSION: Childhood OAS may have different mechanisms from adulthood OAS which almost always accompanies with pollinosis or latex allergy.  相似文献   
90.
A series of pseudo-peptide analogs of the Arg-Gly-Asp (RGD) sequence of fibronectin have been synthe-sized, and their anti-metastatic effects in mice and inhibitory effects on tumor cell invasion in vitro have been examined. The partially modified retro pseudo-peptide of RGD, Rrev-COCH2CO-D (FC-63), was more effective in inhibiting tumor metastasis than the original RGDS peptide. Replacement of the malonyl moiety of FC-63 with a carboxyethylene linkage (Rrev-COCH2CH2-D, FC-303 ) achieved more potent inhibition of lung metastasis of melanoma cells than FC-63. Among the analogs, FC-336, a p-xylylendiamine derivative having two FC-303 moieties, showed the most potent inhibitory effect on experimental lung metastasis produced by i.v. co-injection with B16-BL6 melanoma or colon 26 M3.1 cells in a dose-dependent manner. Multiple administrations of FC-336 after tumor inoculation also showed efficient therapeutic potency against spontaneous lung metastasis of B16-BL6 melanoma in mice. Furthermore, FC-336 effectively inhibited the invasion, migration and adhesion of tumor cells in vitro, but its inhibitory effects were not more than those of RGDS peptide. Zymography analysis revealed that FC-336 inhibited the degradation of gelatin substrate by matrix metalloproteinases (MMPs) produced by tumor cells, while the RGDS peptide did not affect the enzymatic degradation. These findings indicate that the pseudo-peptides of the RGD sequence, possessing the inhibitory property of the degradation by MMPs differently from original RGD-containing peptides, may be advantageous and useful in preventing tumor metastasis. © Rapid Science 1998  相似文献   
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