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排序方式: 共有7391条查询结果,搜索用时 31 毫秒
31.
Ultraviolet radiation (UVB) in sunlight is known to have multiple effects on the immune system. Evidence suggests that UVB-induced immunosuppression is mediated in part by immunosuppressive and immunoregulatory cytokines. Our studies have utilized gene-targeted mutant mice to determine key molecular requirements essential for the development of UVB-induced immunosuppression. Preliminary results from our laboratory suggest that TNF-α plays a regulatory role in contact hypersensitivity, but is not a crucial factor for UVB-induced immunosuppression, and that multiple factors are involved in the induction of UVB mediated immunosuppression. 相似文献
32.
Seiji Nakata Jin Sato Kyoichi Imai Hidetoshi Yamanaka Yoshio Ichinose 《International journal of urology》1995,2(3):191-197
Background Prostate cancer is rare in Asia, but the number of patients is increasing in Japan. We conducted an epidemiological study of prostate cancer in Gunma Prefecture, Japan, to investigate the trends and characteristics of the disease.
Methods: The subjects were 1.411 prostate cancer patients newly diagnosed between 1985 and and 656 patients who died from prostate cancer between 1981 and 1992. The incidence and mortality rates were calculated by year, demographic region and age.
Results: The yearly incidence rate showed an increase but the mortality rate showed no marked fluctuations. There was no significant difference between urban and ruraI districts in either incidence or mortality rate. The incidence rate tended to be high in the northern part of the prefecture, but no marked variation in mortality rate was seen. The incidence and mortality rates in districts with a history of manganese mining were high compared to those in districts without mining. In contrast, the incidence and mortality rates in districts with a history of zinc mining were comparatively lower. Both incidence and mortality rates showed a marked increase with age. The age-specific incidence showed a double logarithmic relationship to age.
Conclusions: The increase of the yearly incidence rate might be due to changes in lifestyle and environmental factors, improved diagnostic techniques, and increased awareness among the general public regarding prostate disease. Further investigation is needed to clarify the pattern and the causes of regional differences in the incidence and mortality rates. The possibilities that manganese and zinc might be related to prostatic carcinogenesis are suggested. Int J Urol 1995:2:191–197 相似文献
Methods: The subjects were 1.411 prostate cancer patients newly diagnosed between 1985 and and 656 patients who died from prostate cancer between 1981 and 1992. The incidence and mortality rates were calculated by year, demographic region and age.
Results: The yearly incidence rate showed an increase but the mortality rate showed no marked fluctuations. There was no significant difference between urban and ruraI districts in either incidence or mortality rate. The incidence rate tended to be high in the northern part of the prefecture, but no marked variation in mortality rate was seen. The incidence and mortality rates in districts with a history of manganese mining were high compared to those in districts without mining. In contrast, the incidence and mortality rates in districts with a history of zinc mining were comparatively lower. Both incidence and mortality rates showed a marked increase with age. The age-specific incidence showed a double logarithmic relationship to age.
Conclusions: The increase of the yearly incidence rate might be due to changes in lifestyle and environmental factors, improved diagnostic techniques, and increased awareness among the general public regarding prostate disease. Further investigation is needed to clarify the pattern and the causes of regional differences in the incidence and mortality rates. The possibilities that manganese and zinc might be related to prostatic carcinogenesis are suggested. Int J Urol 1995:2:191–197 相似文献
33.
Seiji Kinugasa Shuichi Tachibana Manpei Kawakami Tatsuhiko Orino Ryuichi Yamamoto Shinjiro Sasaki 《Surgery today》1998,28(3):335-338
(Received for publication on Nov. 14, 1996; accepted on May 12, 1997) 相似文献
34.
Seiji Naito Katsuo Sueishi Fumitada Hattori Kenzo Tanaka 《Virchows Archiv : an international journal of pathology》1980,387(3):251-257
Summary Immunological similarities or differences between urokinase and plasminogen activators from 9 lines of cultured human caner cells with varying degrees of fibrinolytic activity were examined with antibodies against human urokinase.The antibodies completely inhibited the fibrinolytic activity of 4 lines of gastric cancer, 2 lines of lung cancer, 1 line of urinary bladder cancer and 1 line of renal cancer, indicating that the plasminogen activators from these cell lines were immunologically identical to urokinase. In 5 out of these cell lines, immunological identity was also confirmed by double diffusion analysis.The plasminogen activator from 1 line of lung cancer was found to be immunologically dissimilar to urokinase by a neutralization experiment and double diffusion analysis.These findings indicate that there are at least two immunologically distinguishable forms of plasminogen activators from human cancer cells. 相似文献
35.
36.
Hanibuchi M Yano S Nishioka Y Yanagawa H Miki T Sone S 《Clinical & experimental metastasis》2000,18(5):353-360
The formation of metastases in multiple organs and acquired multi-drug resistance (MDR) are the major obstacles for treatment
of human small-cell lung cancer (SCLC). To explore the possibility of immunological overcoming of multiple-organ metastases
produced by refractory SCLC, we established the MDR variant (SBC-3/DOX), expressing P-glycoprotein, of parental SBC-3 cells
by culturing with gradually increasing concentration of adriamycin. Both SBC-3 and SBC-3/DOX cells expressed a high amount
of ganglioside GM2, an ideal target of SCLC cells. A mouse-human chimeric anti-GM2 monoclonal antibody (KM966) induced antibody-dependent
cellular cytotoxicity (ADCC) mediated by human mononuclear cells (lymphocytes and monocytes) and complement-dependent cytotoxicity
(CDC) mediated by human AB serum against SBC-3/DOX cells to a similar extent compared with parental SBC-3 cells. Pretreatment
of human effector cells with various cytokines induced further enhancement of the KM966-dependent ADCC against SBC-3/DOX cells.
Intravenous injection of SBC-3 or SBC-3/DOX cells into natural killer (NK) cell-depleted severe combined immunodeficient (SCID)
mice developed metastases in multiple organs (liver, kidneys and lymph nodes). Interestingly, SBC-3/DOX cells produced metastases
more rapidly than SBC-3 cells, suggesting more aggressive phenotype of SBC-3/DOX cells than their parental cells in vivo. Systemic treatment with KM966, given on days 2 and 7, drastically inhibited the formation of multiple-organ metastases produced
by both SBC-3 and SBC-3/DOX cells, indicating that KM966 can eradicate metastasis by SCLC cells irrespective of MDR phenotype.
These findings suggest that the mouse-human chimeric KM966 targets the GM2 antigen, and might be useful for the immunological
circumvention of multiple-organ metastases of refractory SCLC.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
37.
Transcription factor Ets-1 mediates ischemia- and vascular endothelial growth factor-dependent retinal neovascularization 总被引:10,自引:0,他引:10
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38.
Matsuzaki Y Sato K Sugawara K Takashita E Muraki Y Morishita T Kumagai N Suzuki S Hongo S 《Journal of clinical microbiology》2005,43(2):993-995
An influenza C virus was isolated from a Japanese traveler who had visited Malaysia in April 1999. Phylogenetic analysis indicated that the genome composition of this virus was distinct from that of any other strain isolated in Japan. The possibility that a genetically unique influenza C virus was introduced into Japan by a traveler is shown. 相似文献
39.
Nishio J Iwasaki H Sakashita N Haraoka S Isayama T Naito M Miyayama H Yamashita Y Kikuchi M 《Human pathology》2003,34(3):246-252
Undifferentiated (embryonal) sarcoma of the liver (UESL) is a rare pediatric liver malignancy that is extremely uncommon in middle-aged individuals. We studied 2 cases of UESL in middle-aged adults (1 case in a 49-year-old woman and the other in a 62-year-old man) by histology, immunohistochemistry, and electron microscopy to clarify the cellular characteristics of this peculiar tumor. One tumor showed a mixture of spindle cells, polygonal cells, and multinucleated giant cells within a myxoid matrix and also revealed focal areas of a storiform pattern in a metastatic lesion. The other tumor was composed mainly of anaplastic large cells admixed with few fibrous or spindle-shaped components and many multinucleated giant cells. In both cases, some tumor cells contained eosinophilic hyaline globules that were diastase resistant and periodic acid-Schiff positive. Immunohistochemically, the tumor cells showed positive staining for smooth muscle markers, such as desmin, alpha-smooth muscle actin, and muscle-specific actin, and also for histiocytic markers, such as alpha-1-antitrypsin, alpha-1-antichymotrypsin, and CD68. Electron microscope examination revealed thin myofilaments with focal densities and intermediate filaments in the cytoplasm of tumor cells. Our studies suggest that UESL exhibits at least a partial smooth muscle phenotype in middle-aged adults, and this specific differentiation may be more common in this age group than in children. Tumor cells of UESL with smooth muscle differentiation in middle-aged adults show phenotypic diversity comparable to those of malignant fibrous histiocytoma with myofibroblastic differentiation. 相似文献
40.
A Raman microprobe spectroscopy characterization of microscopic fracture mechanisms is presented for a natural hydroxyapatite material (cortical bovine femur) and two synthetic hydroxyapatite-based materials with biomimetic structures-a hydroxyapatite skeleton interpenetrated with a metallic (silver) or a polymeric (nylon-6) phase. In both the natural and synthetic materials, a conspicuous amount of toughening arose from a microscopic crack-bridging mechanism operated by elasto-plastic stretching of unbroken second-phase ligaments along the crack wake. This mechanism led to a rising R-curve behavior. An additional micromechanism, responsible for stress relaxation at the crack tip, was recognized in the natural bone material and was partly mimicked in the hydroxyapatite/silver composite. This crack-tip mechanism conspicuously enhanced the cortical bone material resistance to fracture initiation. A piezo-spectroscopic technique, based on a microprobe measurement of 980 cm(-1) Raman line of hydroxyapatite, enabled us to quantitatively assess in situ the microscopic stress fields developed during fracture both at the crack tip and along the crack wake. Using the Raman piezo-spectroscopy technique, toughening mechanisms were assessed quantitatively and rationally related to the macroscopic fracture characteristics of hydroxyapatite-based materials. 相似文献