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排序方式: 共有3119条查询结果,搜索用时 15 毫秒
51.
Hachida M Lu H Ohkado A Gu H Zhang XL Furukawa H Nakanishi T Koyanagi H 《The Journal of cardiovascular surgery》2000,41(4):533-539
BACKGROUND: ATP-sensitive potassium channels have been shown to be one of the important protective mechanisms for the ischemic myocardium. The purpose of this study was to evaluate the protective effect of nicorandil, an ATP-sensitive potassium channel opener, on myocardium during 6 hours hypothermic preservation. METHODS: Preserved rat hearts were randomly divided into 4 groups according to cardioplegia and preservation protocols as follows: (1) histidine-tryptophan-ketoglutarate solution (HTK) for both cardioplegic and immersing solutions (group A); (2) nicorandil-added HTK for cardioplegic solution and nicorandil-free HTK for immersing solution (group B); (3) nicorandil-free HTK for cardioplegic solution and nicorandil-added HTK for immersing solution (group C); and (4) nicorandil-added HTK for both cardioplegic and immersing solutions (group D). RESULTS: The recovery of postischemic cardiac function, including left ventricular developed pressure and end-diastolic pressure, was significantly improved in group B and group C as compared with the other groups (p<0.05). Postischemic intracellular calcium concentration was significantly lower in group B and group C than in group A (p<0.05). CONCLUSIONS: We concluded that nicorandil-induced hyperpolarizing arrest could reduce ischemia-derived myocyte injury and inhibit the influx of calcium into the myocytes in long-term cardiac preservation. 相似文献
52.
Mitral valve replacement was able to be carried out at redo operation requiring neither allogeneic platelet nor blood transfusion in a patient with idiopathic thrombocytopenic purpura, by means of preoperative high-dose intravenous gamma-globulin, autologous blood predonation, use of a centrifugal pump, heparin-coated extracorporeal circuits, and simultaneous splenectomy. 相似文献
53.
A method of heart retraction during coronary artery bypass operations is described. The technique improves exposure of the coronary arteries, especially of the circumflex and posterior descending coronary branches during grafting. In addition, it is simple, safe, and inexpensive. Furthermore, this technique can be applied for off-pump coronary artery bypass surgery. 相似文献
54.
55.
Dayton D. McMillan Junko Maeda Justin J. Bell Matthew D. Genet Garrett Phoonswadi Kelly A. Mann Susan L. Kraft Hisashi Kitamura Akira Fujimori Yukie Yoshii Takako Furukawa Yasuhisa Fujibayashi Takamitsu A. Kato 《Journal of radiation research》2015,56(5):784-791
Radioactive copper (II) (diacetyl-bis N4-methylthiosemicarbazone) (Cu-ATSM) isotopes were originally developed for the imaging of hypoxia in tumors. Because the decay of a 64Cu atom is emitting not only positrons but also Auger electrons, this radionuclide has great potential as a theranostic agent. However, the success of 64Cu-ATSM internal radiation therapy would depend on the contribution of Auger electrons to tumor cell killing. Therefore, we designed a cell culture system to define the contributions to cell death from Auger electrons to support or refute our hypothesis that the majority of cell death from 64Cu-ATSM is a result of high-LET Auger electrons and not positrons or other low-LET radiation. Chinese hamster ovary (CHO) wild type and DNA repair–deficient xrs5 cells were exposed to 64Cu-ATSM during hypoxic conditions. Surviving fractions were compared with those surviving gamma-radiation, low-LET hadron radiation, and high-LET heavy ion exposure. The ratio of the D10 values (doses required to achieve 10% cell survival) between CHO wild type and xrs5 cells suggested that 64Cu-ATSM toxicity is similar to that of high-LET Carbon ion radiation (70 keV/μm). γH2AX foci assays confirmed DNA double-strand breaks and cluster damage by high-LET Auger electrons from 64Cu decay, and complex types of chromosomal aberrations typical of high-LET radiation were observed after 64Cu-ATSM exposure. The majority of cell death was caused by high-LET radiation. This work provides strong evidence that 64Cu-ATSM damages DNA via high-LET Auger electrons, supporting further study and consideration of 64Cu-ATSM as a cancer treatment modality for hypoxic tumors. 相似文献
56.
Absorption,distribution, metabolism and excretion of novel phosphodiesterase type 4 inhibitor ASP3258 in rats
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Yoshiaki Ohtsu Takuya Sonoda Yoko Susaki Toshifumi Tohda Yasuhisa Fukunaga Takafumi Iwatsubo Kiyoshi Noguchi 《Biopharmaceutics & drug disposition》2015,36(1):34-48
The potent and selective phosphodiesterase 4 inhibitor ASP3258 is a novel therapeutic agent for asthma and chronic obstructive pulmonary disease (COPD). After a single oral administration to rats, ASP3258 is rapidly absorbed with a bioavailability of 106%. In situ absorption data indicated that ASP3258 is mainly absorbed in the small intestine. Tissue distribution data after oral administration of 14C‐ASP3258 showed rapid and extensive distribution to various tissues. Excluding the gastrointestinal tract, the tissues with the highest concentrations were liver, heart and plasma. Liquid chromatography‐nuclear magnetic resonance spectroscopy data revealed that O‐glucuronidation of the carboxylic acid moiety of ASP3258 (formation of an acyl glucuronide) plays a key role in metabolism. No indication was found that the acyl glucuronide reacted with proteins in plasma or tissues. When 14C‐ASP3258 was orally administered to intact rats, urinary and fecal excretion accounted for 1.3% and 100.6% of the administered radioactivity, respectively. After a single oral administration of 14C‐ASP3258 to bile‐cannulated rats, urinary and biliary excretion accounted for 0.7% and 93.8% of the administered radioactivity, respectively. These findings suggest that fecal excretion via bile plays an important role in the elimination of ASP3258‐derived radioactivity. In vitro metabolic profiles were relatively similar among the species examined, suggesting that our findings in rats may help us to understand pharmacokinetics, efficacy and safety profiles in humans and other species. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
57.
Keisuke Kidoguchi Yasushi Kubota Shun Fujimoto Yasuhisa Sakata Haruna Kizuka-Sano Kyosuke Yamaguchi Hiroshi Ureshino Hiroo Katsuya Toshihiko Ando Motohiro Esaki Shinya Kimura 《Internal medicine (Tokyo, Japan)》2021,60(10):1601
Cronkhite-Canada syndrome (CCS) is a rare polyposis disorder accompanied by alopecia and onychodystrophy. A 63-year-old man with a history of CCS and repeated embolism developed progressive thrombocytopenia and mild anemia. Laboratory testing, a bone marrow examination, and magnetic resonance imaging of the spine resulted in a diagnosis of concurrent aplastic anemia (AA). Paroxysmal nocturnal hemoglobinuria (PNH)-type cells were detected in a peripheral blood specimen. In addition, human leukocyte antigen (HLA) included DRB1*15:01 and DRB1*15:02. Mesalazine was discontinued in consideration of possible drug-induced pancytopenia. Immunosuppressive therapy ameliorated both the gastrointestinal symptoms of CCS and pancytopenia. A common autoimmune abnormality might underlie both CCS and AA. 相似文献
58.
Koyanagi A Kuffó D Gresely L Shenkin A Cuevas LE 《Annals of tropical medicine and parasitology》2004,98(4):391-399
Studies on the serum concentrations of micronutrients in tuberculosis (TB), and their relationship to the acute-phase response (APR), are scarce. The serum concentrations of zinc, copper, selenium and vitamins A and E in 46 smear-positive cases of pulmonary TB (PTB) from Ecuador were therefore compared with those in 10 healthy Ecuadorian volunteers, and the correlations between these concentrations and the serum concentration of C-reactive protein (CRP) were evaluated. Compared with the healthy volunteers, the PTB cases had significantly lower serum concentrations of zinc, retinol and selenium and significantly higher serum concentrations of copper. Both groups had moderately high concentrations of selenium in their sera. The PTB cases who had >50 mg CRP/ litre (a concentration indicative of an APR) had lower serum concentrations of retinol and zinc than the cases with lower CRP concentrations. In patients with PTB, hypozincaemia and hyporetinolaemia are strongly associated with the APR. It is therefore necessary to consider the extent of activation of the APR when interpreting serum micronutrient concentrations in patients with TB. 相似文献
59.
Nakahara S Arimura Y Saito K Goto A Motoya S Shinomura Y Miyamoto A Imai K 《Diseases of the colon and rectum》2008,51(5):598-603
Purpose We investigated the association between steroid responsiveness and single nucleotide polymorphisms of SLC22A4/A5 located within inflammatory bowel disease 5 locus. Our goal is personalized steroid therapy adjusted to match individual
variations in drug responsiveness in each inflammatory bowel disease patient.
Methods Unrelated Japanese cohorts of 94 patients with Crohn’s, 94 patients with ulcerative colitis, and 257 healthy control subjects
were consecutively enrolled in this study. Genotyping and haplotype analysis focusing on steroid responsiveness was performed
by using 15 single nucleotide polymorphisms.
Results The G allele of −368T > G in SLC22A5, in which strong linkage disequilibrium was observed and the limited diversity of three haplotypes was estimated, was significantly
associated with steroid resistance in Japanese patients with Crohn’s disease (P = 0.016). Haplotype analysis between −446C > T and −368T > G in the SLC22A5 promoter region showed that the CG allele appeared to be a risk haplotype for steroid resistance (CG: odds ratio, 4.13; 95
percent confidence interval, 1.41–12.1; P = 0.016).
Conclusions This extensive linkage disequilibrium may form a general risk haplotype for steroid resistance in Crohn’s disease in Japanese.
Further analyses of the pharmacogenomics of steroid responsiveness are warranted to achieve the goal of individualized steroid
therapy against inflammatory bowel disease.
Supported by a grant-in-aid from the Ministry of Health, Labour and Welfare (K.I.), Japan.
Address of correspondence: Yoshiaki Arimura, M.D., First Department of Internal Medicine, Sapporo Medical University, S-1,
W-16, Chuo-ku, Sapporo, 060-8543, Japan. E-mail: arimura@sapmed.ac.jp 相似文献
60.
The relationship between gallbladder disease and smoking and drinking habits in middle-aged Japanese 总被引:1,自引:0,他引:1
Okamoto M Yamagata Z Takeda Y Yoda Y Kobayashi K Fujino MA 《Journal of gastroenterology》2002,37(6):455-462
Background:
Background: Few studies have investigated the association between smoking and ultrasonographically diagnosed gallbladder (GB) disease,
and their results were uncertain. This study was conducted to examine the association between smoking and drinking and GB
diseases.
Methods: A total of 9947 subjects (age, 30–69 years; 4953 men and 4994 women) voluntarily received a paid medical check-up at our
center in Yamanashi Prefecture in Japan. All of the subjects underwent abdominal ultrasonographic (US) examination, a demographic
check, and a biochemical test, and answered a self-administered questionnaire asking about smoking habits and alcohol consumption.
Of the 9947 subjects, 483 had gallstones, 819 had gallbladder polyps, and 169 were in a state of postcholecystectomy. We compared
the findings in this group with the findings in 8417 people (4144 males and 4273 females) with normal gallbladder.
Results: Multiple regression analysis among males showed that cigarette smoking was inversely related to GB polyps (odds ratio, [OR],
0.76; 95% confidence internal [CI], 0.59–0.98 and OR, 0.74; 95% CI, 0.56–0.98, respectively, for current and ex-smokers).
Ex-smokers a showed positive association with the postcholecystectomy state (OR, 2.56; 95% CI, 1.18–5.52). Light drinkers
showed an inverse relation to GB stones (OR, 0.69; 95% CI, 0.49–0.99), and heavy drinkers showed an inverse relation to GB
polyps (OR, 0.68; 95% CI, 0.51–0.90). Current drinkers showed an inverse relation to the postcholecystectomy state (OR, 0.48;
95% CI, 0.28–0.83).
Conclusions: Cigarette smoking was inversely related to gallbladder polyps in males and was positively related to the postcholecystectomy
state. Drinking was inversely related to gallstones, GB polyps, and the postcholecystectomy state in males.
Received: July 19, 2001 / Accepted: November 2, 2001 相似文献