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81.
Toshiyuki Uryu Kenichi Hatanaka Kei Matsuzaki 《Macromolecular chemistry and physics.》1980,181(10):2137-2149
The cationic, ring-opening copolymerization of 1,6-anhydro-2,3,4-tri-O-benzyl-ß-D -glucopyranose with epichlorohydrin, 3,3-bis(chloromethyl)oxetane and 1,3-dioxolane was investigated with phosphorus pentafluoride as catalyst at low temperatures. Besides, copolymerization of 1,6-anhydro-2,3,4-tri-O-methyl-ß-D -glucopyranose with epichlorohydrin was studied. Structure and composition of the copolymers were determined by 1H and 13C NMR spectroscopy, indicating that copolymerization occurred in each combination of monomers. Number-average molecular weights of copolymers were in the range of 1 400 to 22 800. From the specific rotation and 13C NMR spectrum of copolymers, it was revealed that the ring-opening copolymerization of the benzylated 1,6-anhydro-glucopyranose with the cyclic monomers occurred in a stereoregular manner to give the C-1 carbon of glucose unit with α-configuration. Debenzylation of a copolymer prepared from 1,6-anhydro-2,3,4-tri-Obenzyl-ß-D -glucopyranose and 1,3-dioxolane gave a copolymer composed of free sugar units in the polymer main chain. Assignment of 13C NMR spectra of 2,3,4-tri-O-benzyl-ß-D -glucopyranan and of a copolymer of 1,6-anhydro-2,3,4-tri-O-benzyl-ß-ß-glucopyranose with 1,3-dioxolane was attempted. 相似文献
82.
Takasago T Goto Y Hata K Saeki A Nishioka T Taylor TW Iribe G Mohri S Shimizu J Araki J Suga H 《The Japanese journal of physiology》2000,50(2):257-265
Caffeine causes a considerable O(2) waste for positive inotropism in myocardium by complex pharmacological mechanisms. However, no quantitative study has yet characterized the mechanoenergetics of caffeine, particularly its O(2) cost of contractility in the E(max)-PVA-VO(2) framework. Here, E(max) is an index of ventricular contractility, PVA is a measure of total mechanical energy generated by ventricular contraction, and VO(2) is O(2) consumption of ventricular contraction. The E(max)-PVA-VO(2) framework proved to be powerful in cardiac mechanoenergetics. We therefore studied the effects of intracoronary caffeine at concentrations lower than 1 mmol/l on left ventricular (LV) E(max) and VO(2) for excitation-contraction (E-C) coupling in the excised cross-circulated canine heart. We enhanced LV E(max) by intracoronary infusion of caffeine after beta-blockade with propranolol and compared this effect with that of calcium. We obtained the relation between LV VO(2) and PVA with E(max) as a parameter. We then calculated the VO(2) for the E-C coupling by subtracting VO(2) under KCl arrest from the PVA-independent (or zero-PVA) VO(2) and the O(2) cost of E(max) as the slope of the E-C coupling VO(2)-E(max) relation. We found that this cost was 40% greater on average for caffeine than for calcium. This result, for the first time, characterized integratively cardiac mechanoenergetics of the O(2) wasting effect of the complex inotropic mechanisms of intracoronary caffeine at concentrations lower than 1 mmol/l in a beating whole heart. 相似文献
83.
Saruta J Tsukinoki K Sasaguri K Ishii H Yasuda M Osamura YR Watanabe Y Sato S 《Cells, tissues, organs》2005,180(4):237-244
Human saliva chromogranin A (CgA) is clinically promising as a psychological stress marker. However, expression of CgA is poorly understood in humans, although salivary gland localization of CgA in other mammals, such as rodents and horses, has been demonstrated. In the present study, we investigated the expression and localization of CgA in the human submandibular gland (HSG) using various methods. CgA was consistently localized in serous and ductal cells in HSG, as detected by immunohistochemistry and in situhybridization. Reactivity was stronger in serous cells than in ductal cells. In addition, strong immunoreactivity for CgA was observed in the saliva matrix of ductal cavities. Western blotting gave one significant immunoreactive band of 68 kDa in the adrenal gland, HSG and saliva. Finally, CgA was detected in secretory granules of serous and ductal cells by immunoelectron microscopy. In conclusion, CgA in humans is produced by HSG and secreted into saliva. 相似文献
84.
Yasunari Nakamoto Shuichi Kaneko Masao Honda Masashi Unoura Jaehun Cheong Akihisa Harada Kouji Matsushima Kenichi Kobayashi Seishi Murakami 《Journal of medical virology》1994,42(4):374-379
The question was asked whether a predicted envelope protein, considered to be processed from the polyprotein precursor encoded by the putative E2/NS1 region of the hepatitis C virus (HCV) genome, may be observed in HCV-infected humans. Two polyclonal antibodies against recombinant E2/NS1 proteins were prepared and their reactivity tested against liver extracts from HCV-infected patients by immunoblotting analysis. A band corresponding to a size of 44 kDa was detected in liver extracts from patients who were positive for the HCV-specific antibody anti-C100-3 but not in liver extracts from patients who did not have anti-C100-3 antibody. Additionally, no band was detected using preimmune sera or antisera which had been preabsorbed with recombinant E2/NS1 proteins. Deglycosylation studies demonstrated that the 44 kDa protein was a glycosylated form of a 38 kDa protein which corresponds to the predicted molecular weight of the putative E2/NS1 protein. These results suggest that the 44 kDa protein is a product of the E2/NS1 region. Frequent observation of the 44 kDa band in cases of chronic active hepatitis C suggests a correlation between the expression of this protein and the progression of hepatitis. © 1994 Wiley-Liss, Inc. 相似文献
85.
86.
87.
Toshio Morohoshi Tetsuya Hamamoto Toshiaki Kunimura Etsuko Yoshida Mikio Kanda Kenichi Funo Takehisa Nagayama Masayuki Maeda Shunji Araki 《Pathology international》1991,41(12):916-921
A rare case of splenic epidermoid cyst (SEC) of the pancreas discovered in a 32-year-old Japanese female is reported. The lesion, 5x6cm in size including caseous material and serous fluid in the lumen, was discovered by ultrasonography and computed tomography at the tail of the pancreas and was easily removed. Histopathologically, the cystic wall consisted of three components: the inside was lined by mature squamous epithelium with keratinization, the middle layer consisted of splenic pulp with a sinus structure, and the peripheral layer was dense fibrous connective tissue in which some involutional pancreatic ducts and islets were recognized. The literature about SEC of the pancreas is discussed in comparison with other types of epidermoid cyst including lymphoepithelial cyst and dermoid cyst in the pancreas. Acta Pathol Jpn 41: 916 921, 1991. 相似文献
88.
89.
The Complete Nucleotide Sequence of the PanAsia Strain of Foot-and-Mouth Disease Virus Isolated in Japan 总被引:1,自引:0,他引:1
The complete nucleotide sequence of the foot-and-mouth disease virus (FMDV) O/JPN/2000 strain, the PanAsia strain, was determined by cycle sequencing and primer walking. The 5 end of the genome upstream from homopolymeric poly(C) tract (S-fragment) was 367 nucleotides in length, and the remainder of the genome (L-fragment), excepting the poly(A) tail, was 7808 nucleotides. The L-fragment contains a single open reading frame of 6996 nucleotides terminating at a UAA codon 96 bases from the 3 poly(A) sequence. Comparison of sequences shows that the length of the structural and non-structural protein coding regions are identical to those in the O1/Kaufbeuren strain, and no striking differences such as deletion or insertion were observed between them. 相似文献
90.
Sato Y Harada K Sudo Y Watanabe K Nakahama T Morimoto H Nakanuma Y 《Pathology international》2002,52(7):478-482
Autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC) are representative autoimmune liver diseases in which hepatocytes and intrahepatic bile ducts, respectively, are selectively damaged by autoimmune mechanisms. Bile duct injury and loss is characteristic of PBC and chronic non-suppurative destructive cholangitis (CNSDC), in particular, is a histological hallmark of PBC. In this report, we present an unusual case of AIH accompanied by CNSDC-like bile duct injury in a 46-year-old woman. The patient's serum aminotransferase level was abnormally high. The serum levels of alkaline phosphatase, gamma-GTP and IgG were also elevated, but the IgM level was within normal limits. The titer of antismooth muscle antibody (SMA) was 1:80, while antinuclear autoantibody (ANA) and the M2 fraction of antimitochondrial antibody (AMA) were both negative. Liver biopsy disclosed CNSDC-like bile duct injuries and severe interface hepatitis and lobular hepatitis with perivenular zonal necrosis were observed. The aggregate score of the International Autoimmune Hepatitis Group corresponded to the category of probable AIH. Immunohistochemically, histocompatibility leukocyte antigen-DR, which is aberrantly expressed in the damaged bile ducts of PBC, was not found in the injured bile ducts of this case. Laboratory data were much improved by treatment with prednisone, but ursodeoxycholic acid was not effective. Although the possibility of an overlapping syndrome of AIH- and AMA-negative PBC could not be excluded, this case was diagnosed as AIH with CNSDC-like bile duct lesions. 相似文献