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1.
The present study shows that Langerhans cells can be differentiated from Interdigitating cells at the light microscopic level. Superficial lymph nodes and skin taken from necropsies and the lymph nodes of dermatopathic lymphadenopathy (DPL) were used for this experiment. Sections of lymph node and skin were embedded using the acetone, methyl benzoate and xylene (AMeX) method and dendritic cells were immunostained with anti S-100 protein antibody (S-100, and OKT-6 (CD1a) using the restaining method. Langerhans cells in the skin were positive for both CD1a and S-100. Dendritic cells positive for both CD1a and S-100, and dendritic cells positive for S-100, but not for CD1a were observed in superficial lymph nodes. In normal superficial lymph nodes, there were more interdigitating cells than Langerhans cells. The majority of the dendritic cells in the DPL were Langerhans cells. We conclude that the S-100 and CD1a positive cells are Langerhans cells, and the S-100 positive-CD1a negative cells are interdigitating cells.  相似文献   
2.
Summary In colchicine-pretreated cells of sympathetic ganglia, intensely NPY-immunoreactive material was localized within vacuoles and vesicles of the disorganized, widely dispersed Golgi apparatus. Intensely positive large granular vesicles, which are known to be one of major storage sites of various peptides in the autonomic nerve endings, were essentially unobserved in the perikaryal cytoplasm. The present finding provides evidence that one pool of NPY-like immunoreactivity is localized in the Golgi apparatus of colchicine-pretreated as well as normal sympathetic ganglion cells. It is also clear that visualization of NPY-immunoreactive somata by colchicine-pretreatment in the sympathetic ganglia is due to the accumulation of the neuropeptide in the disorganized Golgi stacks instead of increased amount of the large granular vesicles containing NPY.  相似文献   
3.
The cell wall of Fusarium oxysporum f. sp. lycopersici was digested with chitinase to analyze the structure of its chitinous components. In spite of a similar acetylation degree of the cell wall components to that of 25-35% acetylated chitosan, only N-acetylglucosamine disaccharide [(GlcNAc)2] was obtained from chitinase hydrolyzate of the fungal cell wall by CM-Sephadex C-25 column chromatography, while (GlcNAc)2 and several types of deacetylated chitooligosaccharides were separated from that of 25-35% acetylated chitosan. The results indicate that N-acetylglucosamine residues in the polysaccharide chains of the fungal cell wall are most likely condensed into some region, while acetylated residues are more scattered in 25-35% acetylated chitosan.  相似文献   
4.
Cross-linked poly(N-benzyl-4-vinylpyridinium halide) (designated insoluble BVP) was previously reported to capture bacterial cells alive by contact with them. The corresponding linear polymer poly(N-benzyl-4-vinylpyridinium salt) (designated soluble BVP) was found to exhibit antibacterial activity. This soluble pyridinium-type polymer showed strong antibacterial activity against gram-positive bacteria, whereas it was less active against gram-negative bacteria. The antibacterial activity of this cationic, polymeric disinfectant was considerably greater than that of the corresponding monomeric compound and was approximately equal to that of conventional disinfectants such as benzalkonium chloride and chlorohexidine.  相似文献   
5.
Circadian variations in the activities of aldehyde dehydrogenase (ALDH) isozymes in the subcellular fractions of the brain and liver were investigated in male and female mice of C57BL/6J strain. The rhythms in high Km-ALDH activities of brain and liver mitochondrial fractions which existed in ordinary light-dark cycle were not observed in animals maintained in the continuous darkness for two weeks. The rhythms in high Km-ALDH activities of hepatic soluble and microsomal fractions existed in both ordinary cycle and total darkness but the rhythmic phases were different. In the low Km-ALDH activity of hepatic mitochondrial fraction, the circadian rhythm was similar in two lighting conditions. There was sex difference in the existence of the circadian rhythm. It seems that the ALDH activity of mice is influenced by light-dark cycle and sex hormones.  相似文献   
6.
Summary Screening of leucine and alanine dehydrogenases in thermophilicBacillus strains was carried out to develop their utilization for industrial and analytical catalysts. Out of the 28 thermophilic strains tested, four strains,Bacillus sp. DSM 405, 730 and 1521, andB. sphaericus DSM 462, abundantly produce both the enzymes. Both the enzyme activities in these thermophiles are enhanced by addition of the substrates to a polypeptone medium.  相似文献   
7.
Summary An EcoRI 2.7 kbp fragment from Chlorella ellipsoidea chloroplast DNA (cpDNA) cloned in YIp5 was shown to promote autonomous replication in Saccharomyces cerevisiae. The fragment was localized in the small single copy region close to the inverted repeat. The ARS activity (autonomously replicating sequences in yeast) was found to be confined within a subclone of a ca. 300 bp HindIII fragment. Sequence analysis of this fragment revealed its high AT content and the presence of several direct and inverted repeats and a few elements that were related to the yeast ARS consensus sequence. Electron microscopic studies revealed that this sequence did not coincide with the primary replication origin of chloroplast DNA. The functioning of this sequence as a possible origin of plasmid replication in vivo is discussed. This is the first report on Chlorella cpDNA sequence. re]19850821 rv]19851211 ac]19851216  相似文献   
8.
The sea urchin Heliocidaris tuberculata is typical of most echinoids in having a small egg and a feeding larva, while H. erythrogramma has a large egg and modified development through a non-feeding larvae. The carotenoids in the gonads of these two species were investigated from the comparative biochemical points of view. The carotenoid content of the buoyant eggs of H. erythrogramma was approximately 60 times that of the negatively-buoyant eggs of H. tuberculata. With respect to cytoplasmic volume, however, the carotenoid concentration in the eggs of H. tuberculata was approximately twice that in the eggs of H. erythrogramma. In both species β-echinenone was the principal carotenoid found and their carotenoid patterns were similar. It is very interesting from a functional point of view that carotenoid levels per cytoplasmic volume are conserved across most of the species we have examined irrespective of phylogeny and egg size. In light of this result we suggest that carotenoids may play an important role in developing stage in all echinoids including indirect and direct developers.  相似文献   
9.
10.
By using a DNA fragment of Escherichia coli ffh as a probe, the Bacillus subtilis ffh gene was cloned. The complete nucleotide sequence of the cloned DNA revealed that it contained three open reading frames (ORFs). Their order in the region, given by the gene product, was suggested to be ORF1-Ffh-S16, according to their similarity to the gene products of E. coli, although ORF1 exhibited no significant identity with any other known proteins. The orf1 and ffh genes are organized into an operon. Genetic mapping of the ffh locus showed that the B. subtilis ffh gene is located near the pyr locus on the chromosome. The gene product of B. subtilis ffh shared 53.9 and 32.6% amino acid identity with E. coli Ffh and the canine 54-kDa subunit of signal recognition particle, respectively. Although there was low amino acid identity with the 54-kDa subunit of mammalian signal recognition particle, three GTP-binding motifs in the NH2-terminal half and amphipathic helical cores in the COOH-terminus were conserved. The depletion of ffh in B. subtilis led to growth arrest and drastic morphological changes. Furthermore, the translocation of beta-lactamase and alpha-amylase under the depleted condition was also defective.  相似文献   
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