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排序方式: 共有7667条查询结果,搜索用时 15 毫秒
51.
Kenichiro Karasawa Nobuo Sugiura Yusuke Hori Sakaru Suzuki Junichi Onaya Katsukiyo Sakurai Koji Kimata 《Clinical & experimental metastasis》1997,15(2):83-93
Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis. 相似文献
52.
Oral toxicities of Clostridium botulinum type C and D toxins of different molecular sizes. 总被引:1,自引:6,他引:1
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Clostridium botulinum type C progenitor toxins of different molecule sizes, C-L (16S) and C-M (12S), were purified from cultures of strains 573, Stockholm, and CB-19. C-L toxin showed some hemaggglutinin activity, whereas C-M toxin did not. Neither C-L nor C-M toxin was activated upon trypsinization. Molecular dissociation of purified type C-L and C-M toxins into toxic and nontoxic components was demonstrated by sucrose density gradient ultracentrifugation and diethylaminoethyl-Sephadex chromatography at pH 8.0. The molecular construction of type C progenitor toxin appears to be analogous to that reported for botulinum toxins of other types. C-L and D-L toxins showed higher oral toxicities to mice than did C-M or D-M toxin. Such higher oral toxicities were ascribed to the higher stabilities of these toxins in gastric and intestinal juices. 相似文献
53.
Nobuo Tsuda Paritosh Roy Chowdhury Tomayoshi Hayashi Masanobu Anami Masachika Iseki Shigehiko Koga Fukuzo Matsuya Hiroshi Kanetake Yutaka Saito Yoshio Horita 《Pathology international》1997,47(11):778-783
Primary renal angiosarcoma is very rare. To our knowledge, only 15 cases have been reported to date. A 77-year-old Japanese man with a unilateral kidney presented with massive hematuria followed by renal failure. A renal tumor was suspected and a left nephrectomy was performed. The histopathological diagnosis was angiosarcoma of the kidney. A hemorrhagic tumor measuring 10 × 5 cm and clotted blood was found in the modularly area. The atypical tumor cells had a sinusoidal and solid appearance, and showed Immunohistochemically positive reactions for some of the endothelial markers. The patient died about 21 months after the nephrectomy and the autopsy revealed massive metastases to the liver and retroperitoneum. One of the differential diagnoses of the case was anglomyolipoma, because the tumor cells were relatively bland in their histological appearance with entrapped fat cells in the pelvic area. Fifteen case reports with titles that included the term 'hemangiosarcoma/anglosarcoma', 'hemangioendothelloma/endothelloma' or 'vascular sarcoma' of the kidney were reviewed and compared to the present case. 相似文献
54.
Koh Nakazawa Nobuo Itoh Hui-Jun Duan Yuichi Komiyama Hidekazu Shigematsu 《Pathology international》1992,42(9):662-666
A 73-year-old Japanese man with a history of partial gastrectomy due to gastric cancer 4 years previously was admitted because of intermittent fever. The patient developed abdominal pain, erythema, and myalgia in addition to the fever during the final clinical course, and died of acute heart failure. Autopsy disclosed atrophy of the left lobe of the liver and acute myocardial infarction. Neither metastasis nor recurrence of the cancer was observed. Small and medium-sized arteries of the visceral organs showed various stages of necrotizing vasculitis with narrowing of the lumina. The vasculitis was most prominent in the left lobe of the liver and in the heart. Narrowing of the portal vein due to portal tract inflammation in addition to vasculitis of the hepatic arteries may have induced ischemia and infarction, which had resulted in atrophy of the left hepatic lobe. Acta Pathol Jpn 42: 662–666, 1992. 相似文献
55.
Fu J Hato M Ohmae H Matsuoka H Kawabata M Tanabe K Miyamoto Y Leafasia JL Chinzei Y Ohta N 《Parasitology research》2000,86(5):345-351
We analyzed the relationships between levels of antibody specific for merozoite surface glycoprotein-1 (MSP1) of Plasmodium falciparum and clinical manifestations in humans. We prepared recombinant MSP1 proteins representing block 3 (M3), block 6 (M6), blocks
1–6 (M1/6), and block 17. When we divided the slide-positive individuals in Guadalcanal into symptomatic and asymptomatic
groups, the former group showed lower IgG levels against M6 and block 17, but not against M3, than did the asymptomatic group
(P < 0.01). The possibility of nonspecific suppression was unlikely, given that the levels of antibody against poliomyelitis
virus observed in the two groups were almost the same. Among the IgG subclasses tested, production of cytophilic IgG3 seemed to be dominant. When we analyzed epitopes recognized by antibodies against block 17, a peptide (SSSNFLGIS) was preferentially
recognized by sera from asymptomatic individuals. These results suggest that clinical symptoms occurring during falciparum
malaria seem to be associated with the development of levels of antibody against particular epitopes on MSP1, which is under
the control of an immunoregulatory mechanism.
Received: 1 October 1999 / Accepted: 21 October 1999 相似文献
56.
Nobukatsu Nemoto Yu Nagase Jiro Abe Hiroshi Matsushima Yasuo Shirai Nobuo Takamiya 《Macromolecular chemistry and physics.》1995,196(7):2237-2249
Side-chain functionalized polysiloxanes were prepared via polymer-analogous esterification of poly[(3-chloroformylpropyl)methylsiloxane] with 4-(4-hydroxyphenylazo)nitrobenzene ( P1 ), 4-[4-(ω-hydroxyalkyloxy)phenylazo]nitrobenzene ( P2 – P4 ), 4-{4-[N-(2-hydroxyethyl)-N-methyl]anilinoazo}nitrobenzene ( P5 ), 4-(4-hydroxypiperidino)nitrobenzene ( P6 ), or 4-[4-(2-hydroxyethyl)piperidino]nitrobenzene ( P7 )., P1 , P3 , P4 and P5 exhibit liquid crystallinity, as deduced from differential scanning calorimetry, polarized microscopic observations and X-ray diffraction measurements. The liquid-crystalline phase of P1 and P5 is a nematic phase, and that of P3 and P4 is a smectic one. The second harmonic generation (SHG) measurement of a spin-coated film of P1 was carried out by the Maker fringe method using a Q-switched Nd:YAG laser (1064 nm). The SHG profile after the heat treatment of a spin-coated film suggests a perpendicular orientation of the mesogenic molecules to the glass substrate. The SH light intensity of a corona-poled film was 20-fold higher than that of a film which was only heated, though no differences were observed in their UV-vis absorption spectra. These findings suggest that the mesogenic-molecular dipole moments are aligned to the same direction in the crystalline or liquid-crystalline phase by a poling treatment. 相似文献
57.
58.
Statistical detection of HLA and disease association 总被引:1,自引:0,他引:1
Katsuhirci Fukuda Kazuaki Sugawa Akemi Wakisaka Junko Mokiuchi Nobuo Matsuura Yoshiharu Sato 《Tissue antigens》1985,26(2):81-86
59.
Masaru Enomoto Akihiro Tamori Madoka Toyama Kohmoto Takehiro Hayashi Hisato Jomura Daiki Habu Hiroki Sakaguchi Tadashi Takeda Norifumi Kawada Shuichi Seki Susumu Shiomi Noritoshi Koh Shuhei Nishiguchi 《Journal of interferon & cytokine research》2007,27(3):201-207
Sequential treatment with lamivudine and interferon (IFN) has induced sustained biochemical and virologic responses in the majority of patients with chronic hepatitis B in France. However, the efficacy of sequential treatment in patients with chronic hepatitis B virus (HBV) genotype C infection has not been evaluated. Twenty-four HBe antigen-positive patients were treated with 100 mg lamivudine alone for 16-32 weeks, then with both 6 MU IFN-beta and lamivudine for 4 weeks, and lastly with IFN-beta alone for 20 weeks. Sustained response was achieved in 7 (29%) patients 24 weeks after the end of therapy. No lamivudine-resistant variants emerged in any patient. Hepatitis flare occurred in 3 patients after the withdrawal of lamivudine, but none had decompensation. The patients with sustained response were significantly younger at baseline (p = 0.033) and had a significantly lower HBV DNA level at the start of IFN (p = 0.020) than those without sustained response. In conclusion, the rate of response to sequential therapy with lamivudine and IFN in HBe antigen-positive patients with HBV genotype C infection was lower than the rate reported previously. Patients who were young or who had a favorable virologic response to lamivudine were more likely to have a sustained response. 相似文献
60.
Huh WK Oono T Shirafuji Y Akiyama H Arata J Sakaguchi M Huh NH Iwatsuki K 《Journal of molecular medicine (Berlin, Germany)》2002,80(10):678-684
Defensins are cationic antimicrobial peptides with a broad spectrum. Recently human beta-defensin 2 (hBD-2) has been isolated from psoriatic skin; however, its exact localization and fate have not been fully understood. We studied the distribution pattern of hBD-2 in skin tissues of psoriasis and other inflammatory skin diseases. In the upper spinous and granular layer of psoriasis vulgaris hBD-2 was present in the cytoplasm. In the horny layer the positive signals were in a basket-weave pattern, indicating possible accumulation of hBD-2 in the intercellular space. The similar pattern of hBD-2 distribution was observed in the lesions of nummular eczema and atopic dermatitis. hBD-2 was not detected in the section of normal elbow and knee skin. When isolated psoriatic scales were stained, hBD-2 was detected in a wrapping paper-like distribution pattern surrounding the corneocytes. In horny layer of psoriatic skin hBD-2 was closely associated or colocalized with elafin, which is known to be in extracellular space, as demonstrated by double staining. Western blot analysis using cultured human keratinocytes detected hBD-2 with an expected size in the conditioned medium and in the cell lysates when stimulated with 5% FCS or IL-alpha. These results indicate that hBD-2 was synthesized and remained in cytoplasm in the upper spinous and granular layer, and then secreted into intercellular space in the horny layer. This dynamic change in hBD-2 distribution in epidermis is certainly relevant to function as an innate host defense mechanism against invading micro-organisms. 相似文献