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121.
The female patient was diagnosed as having Von Gierke's disease at 14 years of age, based on clinical manifestations, laboratory examination and liver biopsy. At 19 years of age she had uremia and died from its deterioration at 24 years of age. The parents were consanguineous, and a 27-year-old sister is presently hospitalized for renal Insufficiency with hepatomegaly. On autopsy, the patient's kidneys were highly contracted and contained a number of small cysts, mainly in the medulla. Histological examination indicated periglomerular fibrosis, glomerular hyalinization, tubular atrophy or cystic dilatation and intersitial fibrosis with round cell infiltration. These findings correspond to Fanconi's familial juvenile nephronophthlsis, except for age. The liver was markedly enlarged and Indicated severe glycogen deposits, but the kidney did not contain glycogen deposits. It can, therefore, be presumed that the renal lesions were not a secondary consequence of long-term glycogen deposits but that renal and hepatic lesions were associated with each other.  相似文献   
122.
1. Impulse discharges in single chorda tympani fibres of rats and hamsters in response to gustatory stimuli representing the four basic qualities of taste as well as to cooling and warming of the tongue were recorded.2. In both rats and hamsters many fibres responded to more than one kind of gustatory stimulus as well as to thermal ones. The thermal sensitivity of these fibres was found to be about -0.5 impulses/sec. degrees C for cooling and 0.5 impulses/sec. degrees C for warming.3. Statistical calculations of the frequency of responses of chorda tympani fibres to single gustatory stimuli or combinations of stimuli were made, assuming that responsiveness to any one stimulus is independent of that to other stimuli. Evidence for relatively specific sensitivity to a particular stimulus or a particular combination of stimuli was obtained in the rat and the hamster.4. Across-fibre correlation coefficients between the amounts of responses to a pair of stimuli were calculated. In both the rat and the hamster, significant positive correlations were obtained with HCl, quinine and cooling. In addition, a positive correlation between sucrose and warming and a negative correlation between sucrose and NaCl were obtained in the hamster. The results are discussed in relation to the interaction of gustatory and thermal sensations of the human tongue.  相似文献   
123.
A 41,000-molecular-weight fimbrial protein was isolated from freshly cultivated whole cells of Bacteroides gingivalis 381 and purified chromatographically. Salivary and serum antibody responses to the fimbriae, which had been orally administered in the presence of an acyl derivative of muramylpeptides, i.e., either N2-[(N-acetylmuramyl)-L-alanyl-D-isoglutaminyl]-N6-stearoyl-L-lysine [MDP-Lys(L18)] or sodium beta-N-acetyl-glucosaminyl-(1----4)-N-acetylmuramyl-L-alanyl-D-isoglu tam inyl- (L)-stearoyl-(D)-meso-2,6-diaminopimelic acid-(D)-amine-D-alanine (GM-53), or in the absence of adjuvant, were examined in BALB/c mice when administered by gastric intubation on days 0 and 1 as primary immunizations and on days 27 and 28 as booster immunizations. Gastric intubation of the fimbriae with an adjuvant significantly enhanced the production of anti-fimbria immunoglobulin A (IgA) in saliva. Subcutaneous injection of fimbriae along with an adjuvant also raised anti-fimbria IgA levels, as well as IgG levels, in saliva. Both immunization procedures enhanced the levels of anti-fimbria IgG, IgA, and IgM in serum, and the major class of fimbria-specific antibody was IgG, followed by IgA and IgM. However, subcutaneous injection was more effective than gastric intubation to enhance the production of serum antibody in mice. The subclasses of IgG antibody specific for fimbriae in serum were mainly IgG1, followed by IgG2a, IgG2b, and IgG3. These results demonstrated that the combined use of B. gingivalis fimbrial antigen and either GM-53 or MDP-Lys(L18) resulted in a sharply increased IgA antibody response in saliva and a predominantly stimulated IgG antibody response in serum, respectively. Both antibodies were found to be specific for the fimbriae used for immunization.  相似文献   
124.
A case with tumorous deformity of the posterior mitral valve leaflet after spontaneous chordal rupture in a child is described. A partial rupture in the chordae tendineae of the posterior mitral leaflet was found by echocardiography in a 9-year-old Japanese boy. Tumorous bulging was gradually developed in the leaflet and was surgically excised 5 years later. Multiple nodular tumors were found on the atrial surface of the posterior mitral leaflet. Histological examination revealed that the tumorous bulging consisted of myxomatous materials in which collagen fibrils and very fine elastic fibers were distributed loosely and irregularly. Normal-looking endothelial cells covered the luminal surface of the bulging lesion. Vimentin-positive spindle-shaped mesenchymal cells were scattered in the bulge area. The labeling index of proliferating cell nuclear antigen (PCNA) in these cells was 29.3%. These spindle cells were positive for matrix metalloproteinase (MMP)-1 in the entire bulge area. The cells and matrix were positive for MMP-2 and tissue inhibitor of MMP (TIMP)-1 in the basal area of bulging, but were weakly positive or negative at the surface area. Reactivity for TIMP-2 in the cells in the bulge area was obviously weaker than that in the cells at the spongiosa of the anterior mitral leaflet, which was obtained from the patient at the valve replacement operation 9 months after the initial operation. These findings indicated that the tumorous deformity of the mitral valve was formed by the overgrowth of valve tissue under the stimulation of mitral regurgitation in this child, and the imbalance of MMP and TIMP might play an important role in the bulge formation.  相似文献   
125.
Expression of CD10 by stromal cells during colorectal tumor development   总被引:6,自引:0,他引:6  
CD10 is a cell surface metalloprotease expressed by a variety of normal cell types, including lymphoid precursor cells, germinal center B lymphocytes, and some epithelial cells. We noticed that stromal cells of some cancers are positive for CD10. In this study, we investigated the role of CD10 produced by the stromal cells of colorectal neoplasms in the progression of colorectal neoplasms. Immunohistochemical examination of CD10 and p53 was performed in 169 colorectal epithelial neoplasms representing various stages of carcinogenesis. The results were correlated with the morphologic characteristics of the neoplasms. There was no expression of CD10 in the stromal cells of normal colorectal tissue. CD10-positive stromal cells were present adjacent to the tumor cells in 16 of 73 adenomas with mild or moderate dysplasia. More frequent expression of CD10 by the stromal cells was detected in adenomas with severe dysplasia (12 of 17), intramucosal carcinomas (10 of 16), and invasive carcinomas (50 of 63) than in adenomas with mild or moderate dysplasia (P < 0.0001). Expression of CD10 by > 10% of the stromal cells was detected only within the area of the invasive growth front of invasive carcinomas, not in adenomas and in only 1 of the intramucosal carcinomas. The difference between invasive and non invasive tumors was significant (P < 0.0001). The stromal expression of CD10 was significantly associated with the accumulation of p53 and a larger tumor size. These results indicate that CD10 expression is an integral part of colorectal carcinogenesis. CD10 expression seems to contribute to the invasion and thus probably facilitates metastasis.  相似文献   
126.
Recent studies have indicated that bone marrow cells can regenerate damaged muscles and that they can adopt phenotypes of other cells by cell fusion. Our direct visualization system gave evidence of massive muscle regeneration by green fluorescent protein (GFP)-labeled CD45+c-Kit+Sca-1+Lin- cells (KSL cells), and we investigated the role of KSL cells in muscle regeneration after transplantation with or without lethal irradiation. In the early phase, GFP signals were clearly observed in all the muscles of only irradiated mice. Transverse cryostat sections showed GFP+myosin+ muscle fibers, along with numerous GFP+ hematopoietic cells in damaged muscle. These phenomena were temporary, and GFP signals had dramatically reduced 30 days after transplantation. After 6 months, GFP+ fibers could hardly be detected, but GFP+c-Met+ mononuclear cells were located beneath the basal lamina where satellite cells usually exist in both conditioned mice. Immunostaining of isolated single fibers revealed GFP+PAX7+, GFP+MyoD+, and GFP+Myf5+ satellite-like cells on the fibers. Single-fiber cultures from these mice showed proliferation of GFP+ fibers. These results indicate two different roles of KSL cells: one leading to regeneration of damaged muscles in the early phase and the other to conversion into satellite cells in the late phase.  相似文献   
127.
Activation of the peripheral protease-activated receptor-2 (PAR-2) triggers nociceptive behaviour and thermal hyperalgesia in rats. The present study created a novel mouse model for PAR-2-triggered nociception, and then examined the roles of NMDA receptors and the nitric oxide (NO) pathway in nociceptive processing by PAR-2. Intraplantar administration of the PAR-2 agonist SLIGRL-NH(2) elicited nociceptive responses in mice, an effect being more specific in mast cell-depleted mice. This PAR-2-triggered nociception was abolished by the NMDA receptor antagonist MK-801, but not the neuronal NO synthase inhibitor 7-nitro indazole. In contrast, the PAR-2-triggered thermal hyperalgesia in rats was blocked by both agents. Our study thus provides a novel mouse model for PAR-2-mediated nociception, and suggests that NMDA receptors are involved in PAR-2-triggered nociception and hyperalgesia, while NO contributes only to the latter.  相似文献   
128.
Step-sections of 96 whole kidneys from 50 chronic hemodialysis patients were subjected to a histopathological and quantitative investigation with regard to the development of renal neoplastic lesions. The range of hemodialysis duration was from 1 to 222 months. A total of 349 renal cell adenomas were found in 41 cases (82%). They were commonly multiple and present bilaterally. Renal cell carcinomas were evident in four cases (8%), with hemodialysis durations of 54, 57, 112 and 222 months. The incidence of adenomas increased in a hemodialysis duration-dependent manner, indicating a high risk of renal cell tumor development in chronic hemodialysis patients. Furthermore, acquired cystic disease of the kidney (ACDK) was also observed in 12 cases (24.0%), where the mean hemodialysis period was 143.4 ± 48.0 months. This value was significantly longer than that of non-ACDK cases (P < 0.001). There was, however, no clear relationship between the appearance of ACDK and renal cell tumors. The present results underline the necessity for attention to possible neoplasia of the kidney in patients on long-term hemodialysis.  相似文献   
129.
The expression of uroplakins, the tissue-specific and differentiation-dependent membrane proteins of the urothelium, was analyzed immunohistochemically in N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-treated rats and mice during bladder carcinogenesis. Male Fischer 344 rats were treated with 0.05% BBN in the drinking water for 10 wk and were euthanatized at week 20 of the experiment. BBN was administered to male B6D2F, mice; it was either provided at a rate of 0.05% in the drinking water (for 26 wk) or 5 mg BBN was administered by intragastric gavage twice weekly for 10 wk, followed by 20 wk without treatment. In rats, BBN-induced, noninvasive, low-grade, papillary, transitional cell carcinoma (TCC) showed decreased uroplakin-staining of cells lining the lumen but showed increased expression in some nonluminal cells. In mice, nonpapillary, high-grade dysplasia, carcinoma in situ, and invasive carcinoma were induced. There was a marked decrease in the number of uroplakin-positive cells lining the lumen and in nonluminal cells. This occurred in normal-appearing urothelium in BBN-treated mice and in dysplasic urothelium, in carcinoma in situ, and in invasive TCC. The percentage of uroplakin-positive nonluminal cells was higher in control mice than in rats, but it was lower in the mouse than in the rat after BBN treatment. Uroplakin expression was disorderly and focal in BBN-treated urothelium in both species. These results indicate that BBN treatment changed the expression of uroplakins during bladder carcinogenesis, with differences in rats and mice being related to degree of tumor differentiation.  相似文献   
130.
To determine the phage types (PT) of Salmonella enteritidis found in Thailand and to clarify the potential for human infection by S. enteritidis in broiler chicken meat, human and poultry isolates taken from Thailand between 1990 and 1997 were phage typed and analyzed by pulsed-field gel electrophoresis (PFGE). Ten different PT were found among the 302 isolates phage typed, with PT 4 being the most frequent in human (73.9%) and poultry (76.2%) isolates, followed by PT 1 (8.0%), 8 (3.6%), and 7a (2.2%) in human isolates and by PT 7a (4.9%), 1 (3.7%), and 12 (2.4%) in poultry isolates. Of the 53 isolates analyzed by PFGE, 45 showed an indistinguishable pattern (pattern A) by BlnI-digested PFGE and the other 8 isolates showed a very similar pattern that differed by only a few bands. These results indicate the spread of a genetically identical clone of S. enteritidis in humans and poultry in Thailand.  相似文献   
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