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81.
82.
Three common branches of the celiac trunk are the left gastric artery, the splenic artery and the common hepatic artery. The variation of the three branches of the celiac trunk has an importance for the arterial supply to the digestive organs of the upper abdomen. In this study, we present three cases of the gastrosplenic and the hepatomesenteric trunks in Japanese cadavers. Especially, in Case 1, the left inferior phrenic artery arose from the gastrosplenic trunk and the left hepatic artery arose from the left gastric artery. In Cases 2 and 3, the common hepatic artery penetrated the pancreatic parenchyma before reaching liver. In Case 3, the right hepatic artery arose from the hepatomesenteric trunk. 相似文献
83.
K. Taniguchi H. Tsuchie S. Kageyama M. Iwasaki T. Takagi F. Sasao S. Ueda T. Kurimura 《Archives of virology》1998,143(5):881-890
Summary. HIV-1 p17 antigen has been studied for its biological significance in vitro as well as its immunological roles in vivo. By
immunological approach of antibody-binding to HIV-1 p17 antigens of several subtypes in combination with computerized analysis
of those tertial structures, it became evident that, irrelevant of similarity of linear amino acid sequence of different HIV-1
subtypes, a few amino acid substitutions close to or distant from specified epitope(s) affected their tertial structure resulting
in change in ability of its binding to selected antibody. ELISA employing two monoclonal antibodies, A144 and C415, could
detect p17 of subtypes A and B, but not of subtypes C, D, and E. Since the epitope site corresponding to A144 has been reported
to be important for biological activity of p17 of HIV-1, change in tertial structure around this epitope may explain some
difference in biology of HIV-1, such as infectivity of subtypes B and E.
Accepted January 9, 1998 Received October 24, 1997 相似文献
84.
Detection of capsid antigen of human papillomavirus (HPV) in benign lesions of female genital tract using anti-HPV monoclonal antibody. 总被引:3,自引:0,他引:3
T Iwasaki T Sata M Sugase Y Sato T Kurata K Suzuki H Ohmoto S Iwamoto T Matsukura 《The Journal of pathology》1992,168(3):293-300
We established a murine monoclonal antibody (K1H8) to human papillomavirus (HPV) using alkaline-disrupted virions of HPV type 1 (HPV-1) as the immunogen. K1H8 recognized a 57 kD capsid protein of HPV-1 and detected the antigen in paraffin sections of formalin-fixed tissue. With K1H8, we examined immunohistochemically 68 biopsy specimens obtained from the female genital tract. The specimens were histologically condyloma acuminatum or koilocytotic lesions with or without dysplasia and each specimen was found to harbour a single type of genital HPV, such as types 6, 11, 16, 18, 31, 33, 42, 51, 52, 56, and 58, by Southern blot hybridization analysis. The antigen was localized in the nuclei and occasionally in the cytoplasm of squamous cells showing koilocytotic changes. Eighty-four per cent of the specimens (57 cases) showed positivity for the antigen, indicating that K1H8 is a broadly-reactive antibody to various genital HPVs. The results suggest that benign mucosal lesions of the female genital tract are more frequently associated with viral production and are a potential source of transmission. 相似文献
85.
Isao Nakanishi Shogo Katsuda Yoshikatsu Okada Yoshio Oda Fujitsugu Matsubara 《Pathology international》1986,36(2):261-267
Confronting cisternae of the endoplasmic reticulum recognized in tumor cells of 7 cases of osteosarcoma were presented. They were found in the mitotic cells as well as in the cytoplasms of interphase cells. The more the mitotic cells were observed in 1 μm-thick sections, the more frequently those membranous structures were encountered in the corresponding ultrathin sections. In the interphase cells, such structures were located around Golgi apparatus or close to the nucleus. Occasionally, they were composed of a pair of closely apposed cisternae of the nuclear membrane and the rough endoplasmic reticulum. These results seem to indicate that the nuclear envelope which is disrupted and reformed during mitosis in rapidly proliferating cells takes part in the formation of the confronting cisternae of the endoplasmic reticulum. 相似文献
86.
Blood-compatible hollow fibers were successfully prepared from a polymer alloy composed of polysulfone (PSf) and the 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer. To improve the hydrophilicity, fouling-resistance characteristics, and blood compatibility of the PSf hollow fiber in a hemodialyzer, an MPC polymer that can be blended with PSf was synthesized in order to prepare the polymer alloy (PSf/MPC polymer). The contents of the MPC polymer blended in the PSf were 7 and 15 wt%. The PSf/MPC polymer hollow fiber could be prepared by both wet and dry-wet processing methods. The hollow fiber took an asymmetric structure, that is, the hollow-fiber membrane had a dense skin layer on the porous sponge-like structure. The mechanical strength was higher than that of conventional PSf hollow fibers for hemodialysis. The surface characterization of the PSf/MPC polymer hollow fiber by x-ray photoelectron spectroscopy revealed that the MPC units were concentrated at the surface. The permeability for solutes through the PSf/MPC polymer hollow fibers was measured for 4 h. The permeabilities of both a low-molecular-weight compound and protein were greater than those of the PSf hollow fibers. The amount of adsorbed protein was lower on the PSf/MPC polymer hollow fiber when compared to that of the PSf hollow fiber. Moreover, platelet adhesion was also effectively inhibited on the PSf/MPC polymer hollow fiber. Based on these results, the addition of the MPC polymer to the PSf is a very useful method to improve the functions and blood compatibility of the hollow fiber. 相似文献
87.
A Iwasaki 《Medical physics》1985,12(6):731-737
The complete distribution of high-energy photon primary absorbed dose along the beam path within a semi-infinite or finite water phantom can be expressed by one functional equation. The derivation is based on a technique of convoluting a primary collision kerma distribution function with a pair of forward and backward spread dose-distribution functions. In particular, the characteristic patterns of primary dose in the regions near the beam entrance and exit surfaces can be obtained. The calculated ratio of primary dose to primary collision kerma in the electron-equilibrium region in water for 60Co radiation is 1.0060 and that for 25-MV radiation is 1.0444. 相似文献
88.
Masafumi Takahashi Uichi Ikeda Kazuyuki Shimada Tadashi Kasahara Sei-Ichi Kitagawa Yu-Ichi Takahashi Chikao Morimoto Shogo Kano Jun-Ichi Masuyama 《Journal of clinical immunology》1997,17(1):53-62
Interleukin-8 (IL-8) is a chemokine for polymorphonuclear leukocytes (PMNs) and lymphocytes, which promotes the extravasation of these inflammatory cells. In this study, we investigated IL-8 synthesis induced by the adhesive interaction between monocytes and endothelial cells during transmigration and the capacity of transmigrated monocytes to produce IL-8. Cocultured human monocytes and human umbilical vein endothelial cell (HUVEC) monolayers induced the synefgistic production of IL-8, compared with cultures of either monocytes or HUVEC monolayers alone. Coculture-induced IL-8 production almost doubled after HUVECs were stimulated with IL-1. The induced IL-8 mRNA expression was consistent with the protein data, indicating the de novo synthesis of IL-8 by the coculture. Monoclonal antibodies (mAbs) against IL-8 inhibited the transendothelial chemotactic activity of the supernatants for PMNs by 55%. Immunohistochemistry revealed that both adherent and transmigrated monocytes and unstimulated HUVECs expressed IL-8 protein, whereas nonadherent monocytes did little. Transmigrated monocytes spontaneously secreted a 3.8-fold greater amount of IL-8 than the initial monocytes. Coculture-induced IL-8 production was inhibited about 30% by polyclonal Abs against IL-, IL-1, or tumor necrosis factor , while it was not affected by mAbs against intercellular adhesion molecule 1 or vascular cell adhesion molecule 1. The results suggested that adhesive interaction during the transmigration of monocytes through HUVEC monolayers activates both cell types to produce IL-8 and that transmigrated monocytes are capable of producing ample IL-8. 相似文献
89.
Narimatsu E Nakayama Y Aimono M Fujimura N Iwasaki H Namiki A 《Research communications in molecular pathology and pharmacology》1999,104(2):219-228
Phosphodiesterase (PDE) inhibitors are occasionally used in patients receiving non-depolarizing muscle relaxants during anesthesia and intensive care. However, little is known about the influence of PDE III inhibitors on the effects of non-depolarizing muscle relaxants. The aim of this study was to elucidate the effects of milrinone, a PDE III inhibitor, on d-tubocurarine (dTc)-induced muscle relaxation in vitro and then to compare its effects with those of other activators of the adenylate cyclase (AC) system (aminophylline, a non-selective PDE inhibitor; forskolin, a direct AC activator; and isoproterenol, a beta-adrenoceptor agonist). Isometric twitch tensions of rat nerve-hemidiaphragm preparations elicited by indirect or direct stimulation (0.1 Hz) were measured. Indirectly elicited twitch tension partially depressed by dTc (1 microM) was antagonized by milrinone, aminophylline, and forskolin but was attenuated by isoproterenol. Directly elicited twitch tension was increased by aminophylline, forskolin, and isoproterenol but was not altered by milrinone. The results indicate that milrinone antagonizes dTc-induced muscle relaxation by recovering the neuromuscular transmission. It is noteworthy that PDE inhibitors and a beta-adrenergic agonist affect non-depolarizing muscle relaxation in opposite direction. 相似文献
90.
Ryoichi Muraki Toru Baba Takuya Iwasaki Tetsutaro Sata Takeshi Kurata 《Virchows Archiv : an international journal of pathology》1992,420(1):71-76
Summary Thirty-seven biopsy skin tissues of herpes zoster taken from 27 patients were analysed immunohistochemically using two monoclonal antibodies detecting either nucleocapsid or glycoproteins of varicella-zoster virus (VZV) on paraffin sections of formalin fixed tissues. Skin lesions of herpes zoster were divided clinically into four stages: erythematous, vesicular, pustular and ulcerative. In the erythematous stage, VZV antigens, if detected, were found only within ballooning cells in the lower epidermis or follicular epithelium. In the vesicular stage, antigens were detected in the cells around and within the intraepidermal vesicles and in histiocytes or fibrocytes of the dermis in all cases and in the endothelial or perineural cells in 10 of 14 cases. In the pustular stage, the antigens were observed in degenerated or necrotic keratinocytes and multinucleated giant cells within pustules and some necrotic cells in the dermis. In the ulcerative stage, the viral antigens were detected only at the ulcer margin and around the hair shaft in 2 of 7 cases. These results suggest that VZV initially involves the epidermis in the erythematous stage, subsequently invades the dermis in the vesicular stage, and disappears in the early ulcerative stage. 相似文献