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排序方式: 共有1638条查询结果,搜索用时 218 毫秒
81.
Hirotoshi Shima Eiko Koike Ritsuko Shinohara Takahiro Kobayashi 《Toxicological sciences》2006,91(1):218-226
Diesel exhaust particles (DEP) are known to induce adverse biological responses such as inflammation of the airway. However, the relationship between the chemical characteristics of organic compounds adsorbed on DEP and their biological effects is not yet fully understood. In this study, the dichloromethane-soluble fraction (DMSF) from DEP was fractionated into its n-hexane-soluble fraction (n-HSF) and n-hexane-insoluble fraction (n-HISF). Using these DEP fractions, we designed the present studies to elucidate (1) chemical characteristics, (2) biological characteristics, and (3) the relationship between the chemical and the biological characteristics of these DEP fractions. Dithiothreitol (DTT) assay, Fourier transform-infrared (FT-IR) spectroscopy, proton nuclear magnetic resonance (1H-NMR) spectroscopy, and gas chromatography-mass spectrometry (GC-MS) were used to characterize their chemical properties. Heme oxygenase-1 (HO-1) protein expression, viability of rat alveolar type II epithelial cell line (SV40T2), and inflammatory cell infiltration into the peritoneal cavity of BALB/c mice were evaluated as markers of oxidative stress, cytotoxicity, and inflammatory response, respectively. The oxidative ability of the DEP fractions was n-HISF > DMSF > n-HSF. IR, 1H-NMR, and GC-MS spectra showed that n-HISF was mainly composed of compounds having many functional groups related to oxygenation, such as hydroxyl and carbonyl groups. The relative strength of HO-1 protein expression, cytotoxicity, and inflammatory responses was also n-HISF > DMSF > n-HSF. All of the n-HISF-induced biological activities were decreased by reduction with N-acetyl-L-cysteine (NAC). These results suggest that n-HISF has high oxidative ability and many functional groups related to oxygenation and that this ability strongly contributes to the induction of oxidative stress, cytotoxicity, and inflammatory response. 相似文献
82.
Polyurethane-covered wallstents to recanalize wallstents obstructed by tumor ingrowth from malignant common bile duct obstruction 总被引:4,自引:0,他引:4
Nakamura T Kitagawa M Takehira Y Yamada M Kawasaki T Nakamura H 《Cardiovascular and interventional radiology》2000,23(2):161-164
Four patients with malignant obstruction of the common bile duct had been treated with uncovered Wallstents and suffered from a reobstruction after 2-13 months (mean 5.3 months). Repeat cholangiography revealed severe stenosis of the stent lumen caused by tumor ingrowth through the mesh. A Wallstent with a self-made polyurethane-cover was inserted through the uncovered stent in these patients. The four patients were followed for 3-13 months (mean 6.3 months) until death. There was good drainage with no evidence of recurrent obstruction in all patients. We conclude that a covered Wallstent may extend patency of stented bile ducts, preventing tumor ingrowth in patients with neoplastic obstruction. Further observations are needed. 相似文献
83.
Shin Narai Masahiko Watanabe Hirotoshi Hasegawa Hideki Nishibori Takashi Endo Tetsuro Kubota Masaki Kitajima 《International journal of cancer. Journal international du cancer》2002,97(4):508-511
Transforming growth factor β1 (TGF‐β1) is thought to be involved in cancer growth and progression. TGF‐β1 changes to its active form after being secreted in its latent form. Our aim was to clarify the significance of plasma concentrations of active and total TGF‐β1 of patients with colorectal cancer. Plasma concentrations of active and total TGF‐β1 in 45 patients with colorectal cancer and 23 healthy volunteers were measured using ELISA and the activation rate (ratio of active to total TGF‐β1) was determined. Plasma concentrations of active TGF‐β1 (21.9 ± 12.8 pg/ml) were significantly higher in patients with colorectal cancer than in healthy volunteers (9.9 ± 5.9 pg/ml; p < 0.001, Welch's t‐test). Concentration of total TGF‐β1 was also significantly higher for patients with colorectal cancer (18.0 ± 13.0 ng/ml vs. 11.1 ± 6.4 ng/ml; p < 0.01, Welch's t‐test). However, there was no significant difference in the TGF‐β1 activation rate between the 2 groups. There was a correlation between Dukes' stage and plasma concentration of active or total TGF‐β1 (p < 0.01, Spearman's rank correlation test) and on day 7 the active TGF‐β1 levels for patients recovering from curative resection were similar to those of the control group of healthy volunteers. These results suggest that active TGF‐β1 might be used as a tumor marker for colorectal cancer. © 2001 Wiley‐Liss, Inc. 相似文献
84.
GenusCurcumaofthefamilyZingiberaceaeconsistsofabout 70speciesintheworld ,ofwhichmorethantenaredistributedorcultivatedinChina[1] andJapan[2 ] .SeveralherbaldrugsusedfrequentlyarederivedfromtheCurcumaspecies.InChina ,“Jianghuang”fromtherhi zomeofCurcumalonga ,“Pianjianghuang”fromtheslicedrhizomeofC .wenyujin ,“Ezhu”fromtherhizomesofC .phaeocaulis,C .wenyujinorC .kwangsiensis,and“Yujin”fromthetubersofC .wenyujin ,C .longa ,C .kwangsiensisorC .phaeocaulisareinuse .[3] InJapan ,“Gajutsu”fromtherhizomeofC .zedoar... 相似文献
85.
The detection of IRF-1 promoter polymorphisms and their possible contribution to T helper 1 response in chronic hepatitis C. 总被引:3,自引:0,他引:3
Hidetsugu Saito Shinichiro Tada Kanji Wakabayashi Nobuhiro Nakamoto Masahiko Takahashi Mitsuyasu Nakamura Hirotoshi Ebinuma Hiromasa Ishii 《Journal of interferon & cytokine research》2002,22(6):693-700
We described the interferon (IFN) regulatory factor-1 (IRF-1) promoter single nucleotide polymorphisms (SNPs), and the clinical and immunologic implications of these SNPs have been investigated. We successfully determined the mutation at -300 of the IRF-1 promoter by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and this mutation linked with other mutations in the promoter region. In our Japanese population, the frequency of the type -300*A/A was 11.9%, type A/G was 54.2%, and type G/G was 33.9%. We found no significant difference without IFN stimulation in the production levels of IFN-gamma and interleukin-10 (IL-10) from peripheral blood mononuclear cells (PBMC) between subjects with -300*A/A and those with other types. IFN-alpha stimulation, however, increased the levels of IFN-gamma significantly and decreased the IL-10 production level significantly only in the subject with -300*A/A type. Flow cytometric analysis showed that the Th1-type CD4(+) cell population was significantly increased by IFN-beta administration only in the patient with chronic hepatitis C with -300*A/A type. These results suggest that the IRF-1 promoter SNP types are positively involved in Th1-type response and, consequently, the -300*A/A type may be beneficial for viral elimination in chronic hepatitis C and IFN therapy. 相似文献
86.
We report a new case of multiple minute digitate hyperkeratoses after postmastectomy irradiation therapy for mammary cancer. This is the first case of multiple minute digitate hyperkeratoses in an Asian country as well as the third report of the disorder after irradiation. The characteristic eruption, the consistent trigger of irradiation and its occurrence in patients of different racial groups indicate that multiple minute digitate hyperkeratoses are a distinct clinical entity. 相似文献
87.
SADAO IMAMURA MASAHIRO TAKIGAWA KOICHI IKAI HANAKO YOSHINAGA† MIZUHO YAMADA† 《Clinical and experimental dermatology》1978,3(3):285-291
A 68-year-old man developed pemphigus foliaceus, myasthenia gravis with a spindle cell thymoma, and later died with red cell aplasia. At autopsy, pemphigus affected the oesophageal mucosa, and this finding was confirmed by direct immunofluorescence. In order to clarify the relationship between pemphigus and myasthenia gravis or thymoma, sera from 38 patients with myasthenia gravis were examined. Intercellular epithelial antibodies (IC-AB) at titres of 10-40 were found in 8, when monkey oesophagus was employed as the substrate. IC-AB in sera of patients with pemphigus and or myasthenia gravis did not react to any part of human thymoma, human hyperplastic thymus or monkey normal thymus. Deposits of immunoglobulins or complement were not demonstrated in the human thymoma. 相似文献
88.
Adachi K Yamamoto Y Kameyama E Suzuki H Horinouchi T 《Masui. The Japanese journal of anesthesiology》2005,54(6):653-657
BACKGROUND: Moyamoya disease is a rare neurovascular disorder that requires special anesthetic managements during revascularization procedures. We have investigated the incidence of early postoperative complications under inhaled anesthesia in comparison with total intravenous anesthesia (TIVA) retrospectively. METHODS: Seventy-two patients undergoing revascularization procedures were divided into two groups, one with inhaled anesthesia (n = 23) and the other with TIVA (n = 49). Surgical procedures were performed under normocapnia, proper body temperature, and all patients were prevented from anemia by homologous transfusion. To avoid the variance in anesthetic managements, 39 patients under 15 years of age were picked up and divided in the same way as above. Early postoperative complications including transient ischemic attack and cerebral infarction during the first 2 weeks after operation were investigated. RESULTS: In all patients, early postoperative complications occurred in 48% of inhaled anesthesia group and in 49% of TIVA group. In patients under 15, these complications occurred in 44% and in 57%, respectively. There was no significant difference in the incidence of complications between the two anesthetic groups. CONCLUSIONS: Several previous studies reported the excellence of TIVA for revascularization procedure on the basis of regional blood flow because inhaled anesthesia may provoke intracerebral steal in moyamoya disease. Our investigation in this study revealed that both anesthetic methods have no significant difference in postoperative complications during the first 2 weeks after operation. Thus further study should be needed to verify the safety of inhalation anesthetics in patients with moyamoya disease. 相似文献
89.
PURPOSE: To evaluate the effect of cavity configuration on microtensile bond strengths of two resin composites for core build-up to pulpal floor dentin. METHODS: Access cavity preparation and root canal filling with gutta percha were performed on extracted human molars. Following this, the gutta percha in the pulp chamber was completely removed to expose pulpal floor dentin. The cavity walls remained as a control group (Cavity). For another group, the cavity walls were removed to create a flat surface for bonding (Flat). For the Cavity group, Clearfil SE Bond was applied to the cavity according to the manufacturer's instructions, and either a light-cured resin composite (PH, Clearfil Photo Core) or a dual-cured resin composite (DC, Clearfil DC Core), was placed in the bonded cavity. Clearfil Photo Core was placed in three increments while bulk-filling was used for Clearfil DC Core. The application of the bonding system and the composites to the flat dentin surface was the same as that for cavity. Specimens were stored in water for 1 week, then sectioned vertically into 2 or 3 slabs (0.7 mm thick) and trimmed for the microtensile bond strength (MTBS) test. The MTBSs were measured with a universal testing machine at a crosshead speed of 1.0 mm/minute. RESULTS: The results (mean +/- SD, MPa, n=10) of PH/Cavity, PH/Flat and DC/Flat were 21.9 +/- 3.4, 28.9 +/- 4.0, and 27.6 +/- 6.1 respectively. The MTBS could not be determined in DC/Cavity because of debonding occurred during sample preparation. 相似文献
90.
Suzuki K Suda T Naito T Ide K Chida K Nakamura H 《American journal of respiratory and critical care medicine》2005,171(7):707-713
Unmethylated CpG motifs in bacterial DNA or synthetic oligodeoxynucleotides (ODN) potently stimulate the innate immune system, and they are recognized by Toll-like receptor 9 (TLR9), which is expressed by monocytes/macrophages, dendritic cells, and B cells. However, it is unknown whether alveolar macrophages (AMs) express functional TLR9. To clarify this, we analyzed mRNA expressions of TLRs in murine AMs by real-time polymerase chain reaction, and compared with those in other tissue macrophages and lung antigen-presenting cells. In addition, we determined the sensitivity of these cell populations to CpG-ODN. Interestingly, TLR9 mRNA was almost absent in AMs, but highly expressed in bone marrow-derived macrophages and peritoneal macrophages, whereas TLR2 and TLR4 were present in all macrophage populations. Consistent with the receptor expression, AMs showed no sensitivity to CpG-ODN, whereas other macrophage populations secreted tumor necrosis factor alpha, interleukin 12 p40, and interleukin 6, and enhanced expression of CD40, CD80, and CD86, in response to CpG-ODN. Lung dendritic cells and B cells highly expressed TLR9 mRNA and responded to CpG-ODN. These results indicate selective loss of TLR9 expression in AMs with no sensitivity to CpG-ODN, suggesting that dendritic cells and B cells play a role in the immune response against bacterial DNA in the lung. 相似文献