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121.
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A study was conducted on two brothers with Jordans' anomaly. Fat-containing vacuoles were noticed in all leukocytes of the peripheral blood and cells of the myeloid series including myeloblasts, but the serum lipids showed no abnormalities. However, cells of the erythroid series, megakaryocytes and platelets did not contain these vacuoles. An increase in vacuole number was observed as the leukocytes matured. Histochemically, it was suggested that these vacuoles contained neutral fat based on staining with Sudan III and Nile blue sulfate. Ultrastructurally, these vacuoles were unassociated with lysosomes or other cell organelles. Although the etiology of Jordans' anomaly could not be clarified by this study, genetic factors may be involved.  相似文献   
123.
Clinicopathological features of three autopsy cases of extremely rare late onset type I familial amyloldotic polyneuropathy were presented and compared with 19 autopsy cases of the ordinary type. In the late onset cases, the ages at onset and at death were 27.5 and 24.5 years older, respectively, compared with the ordinary type. Also, duration of the total clinical course form onset to death was 3.7 years less than in the late onset cases. The degree of amyloid deposition was more marked in the heart of the late onset cases, causing prominent cardiac hypertrophy. It was also marked In the kidneys or thyroid of two cases, but slight to moderate in the peripheral or autonomic nervous tissues in all cases. Immunohistochemical Investigation demonstrated the presence of transthyretin (TTR) as an amyloid precursor protein and of serum amyloid P-component in amyloid deposits in various organs and tissues of the late onset type. These findings, as well as serum levels of variant TTR, were similar to those of the ordinary type. These results suggest that there are some factors other than the amyloid precursor protein that effect the degree of amyloid deposition.  相似文献   
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125.
Enterotoxigenic Escherichia coli grown in the presence of lincomycin and tetracycline produced an increased amount of heat-labile enterotoxin (LT). These antibiotics increased the production of not only extracellular LT but also intracellular LT. On the other hand, lincomycin did not stimulate the production of heat-stable enterotoxin by enterotoxigenic E. coli. The extracellular LTs produced in the presence of lincomycin and tetracycline were purified and analyzed by sodium dodecyl sulfate-polyacrylamide gel disc electrophoresis. Results showed that the A subunits of the purified LTs were not nicked, unlike that of extracellular LT produced in the absence of the antibiotics.  相似文献   
126.
Formalin-fixed paraffin-embedded hippocampal sections of brains with early-onset and late-onset Alzheimer's disease were studied immunohistochemically with antisera against cathepsin D and cathepsin B. In addition to the staining of neuronal perikarya, some of the senile plaques visualized by Bielshowsky silver staining and some of reactive astrocytes were positively stained with the antisera against cathepsin D and cathepsin B in brains with Alzheimer's disease. Abnormal localization of cathepsin D and cathepsin B immunoreactivity in neuronal perikarya was observed in brains with early-onset Alzheimer's disease. These findings demonstrate that the distribution of lysosomal proteases was altered in brains with Alzheimer's disease, suggesting the primary and/or secondary involvement of the lysosomal proteases in the pathological process of Alzheimer's disease.  相似文献   
127.
Content and distribution of Met-enkephalin (Met-ENK)-like immunoreactivity in the hypothalamo-hypophysial system of bovine, rat and frog were examined using specific radioimmunoassay and immunohistochemistry. Ultrastructural localization and co-existence of Met-ENK-, mesotocin (MT)- and vasotocin (VT)-like immunoreactivity in the neural lobe of the frog pituitary was examined by a method combining pre-embedding peroxidase-antiperoxidase immunostaining for Met-ENK with post-embedding immunocolloidal gold staining for MT or VT. The highest concentrations of immunoassayable Met-ENK were present in the neural lobe of the pituitary of the frog. In addition to nerve fibers showing only MT-like or Met-ENK-like immunoreactivity, nerve fibers containing neurosecretory granules showing both MT- and Met-ENK-like immunoreactivities were very rich. But VT-like and Met-ENK-like immunoreactivity was confirmed separately in different axon terminals.  相似文献   
128.
The cross-reactivity of antibodies to adult T-cell leukemia (ATL)-associated antigens (ATLA) in human and monkey sera was investigated by indirect immunoperoxidase and immunoferritin methods using a human cell line (MT-2) carrying a type C virus (HTLV), two monkey cell lines (Si-1 and Si-3) carrying HTLV, and a monkey cell line (Si-2) carrying a type C virus isolated from an anti-ATLA-positive monkey. Anti-ATLA-positive but not-negative human and monkey sera gave positive immunoperoxidase reaction with all four virus-positive cell lines when studied by light microscopy. Electron microscopic findings revealed ferritin or peroxidase labeling of virus particles and plasma membranes of these four cell lines with antibody-positive but not-negative human and monkey sera. These results clearly indicate the cross-reactivity of anti-ATLA antibodies in human and monkey sera at light and electron microscopic levels, and the presence of antigenic determinants common to the surface of type C virus particles of human and monkey origin.  相似文献   
129.
130.
In the present study, we established transgenic mice overexpressing Del1, a ligand of integrins, to examine the effect of overexpression of Del1 on vascular morphogenesis. In the wild-type mouse, mesenteric vessels are shaped like rakes consisting of a long stalk and short branches at the periphery. In contrast, those in transgenic mice showed typical dendritic architecture consisting of a few large primary branches with smaller spreading branches. The phenotype of mice overexpressing Del1 suggests the existence of a tissue-specific mechanism for branching morphogenesis in the mesentery.  相似文献   
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