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排序方式: 共有3565条查询结果,搜索用时 15 毫秒
61.
Zhang Lu Wu Lili Liu Ximing Yoshitomi Hisae Ikeda Katsumi Negishi Hiroko Pan Yajing Sun Wen Qin Lingling Li Juan-E Xu Tunhai Liu Tonghua Gao Ming 《中医杂志(英文版)》2018,38(4):548-555
OBJECTIVE
To evaluate whether endothelial dysfunction and hypertension are prevented by trans-cinnamaldehyde (tCA) through the activation of endothelial nitric oxide synthase (eNOS).METHODS
Human umbilical vein endothelial cells (HUVECs) were cultured in vitro and stimulated with tCA to determine cell viability using the methyl thiazolyl tetrazolium assay. The effect of tCA on nitric oxide (NO) production was determined by diaminofluorescein-dyes in the absence or presence of inhibitors of eNOS, AMPK, PKA, and AKT. The effect of tCA on blood pressure was determined by the tail-cuff method in obesity spontaneous hypertension (SHR. Cg-Leprcp/NDmcr) rats. The phosphorylation of eNOS and protein expression of the insulin-signaling pathway (InsR-IRS1-PI3K-AKT) were measured by western blot.RESULTS
tCA at concentrations less than 100 did not affect cell viability in cultured HUVECs. Stimulation with tCA promoted NO release in a time-dependent manner compared with the control group. tCA-treated HUVECs also significantly increased AKT-Ser473 and eNOS- Ser1177 phosphorylation. In SHR-CP rats, treatment with tCA at a dose of 40 mg/kg/day for 6 weeks markedly reduced the systolic blood pressure and diastolic blood pressure, increased the phosphorylation of AKT and eNOS, and increased urinary nitric oxidation.CONCLUSION
tCA attenuated endothelial dysfunction and reduced blood pressure in SHR-CP rats. The underlying mechanisms may involve the increase in AKT and eNOS phosphorylation and the release of eNOS-derived NO. 相似文献62.
Tomomasa Tochio Katsumi Mukai Youichirou Baba Hiroki Asakawa Kenji Nose Satomi Tsuruga Hiroaki Kumazawa Yoshiaki Isono Hiroki Tanaka Shimpei Matsusaki Tomohiro Sase Tomonori Saito Hiroshi Okano Miki Usui Gen Watanabe 《Clinical journal of gastroenterology》2018,11(6):465-469
Primary clear cell adenocarcinoma (CCA) of the colorectum is a rare tumor. We report on a 48-year-old man with early stage CCA in the descending colon who underwent detailed examination with image-enhanced endoscopy, such as magnifying endoscopy with narrow-band imaging and crystal violet staining. The tumor was treated successfully with endoscopic mucosal resection at our hospital. 相似文献
63.
64.
Incidence of gastric adenocarcinoma among lesions diagnosed as low‐grade adenoma/dysplasia on endoscopic biopsy: A multicenter,prospective, observational study
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65.
Spontaneous loss of hepatitis B surface antigen in chronic carriers, based on a long-term follow-up study in Goto Islands, Japan 总被引:3,自引:0,他引:3
Kato Y Nakao K Hamasaki K Kato H Nakata K Kusumoto Y Eguchi K 《Journal of gastroenterology》2000,35(3):201-205
Annual mass examination was performed between 1972 and 1997 in Tomie-town, Goto Islands, Japan, where hepatitis B virus (HBV)
infection is very prevalent. In the present study, the incidence of spontaneous loss of hepatitis B surface antigen (HBsAg)
in HBsAg carriers was determined in this area. Three thousand and nineteen inhabitants were tested for HBsAg two or more times
in our annual surveys. Among them, 131 (4.3%) were defined as chronic HBsAg carriers based on the persistence of HBsAg for
1 or more years. These 131 subjects were followed for 12.2 ± 7.6 years. During the follow-up period, spontaneous loss of HBsAg
occurred in 38 (29%) of the 131 carriers, with a yearly incidence of 2.5%. This loss was seen more frequently in carriers
aged 40 years or more on enrollment than in those aged less than 40 years during the same observation periods (P = 0.0141), irrespective of sex or the results of liver function tests. The values for liver function test results were similar
before and after loss of HBsAg in these carriers. Stored serum samples were available for later analysis of HBV-DNA by polymerase
chain reaction in 32 carriers with loss of HBsAg. The HBV-DNA sequence was detected in 26 (81%) and 2 of the 32 carriers (6%)
before and after loss of HBsAg, respectively. These results indicate that spontaneous loss of HBsAg, largely attributable
to clearance of viremia, occurs age-dependently in chronic carriers.
Received: July 23, 1999 / Accepted: September 24, 1999 相似文献
66.
Hyoe Inomata Takehiro Watanabe Yoko Iizuka Yi-Qiang Liang Tomoji Mashimo Toru Nabika Katsumi Ikeda Kazuyuki Yanai Takanari Gotoda Yukio Yamori Mitsuaki Isobe Norihiro Kato 《Hypertension research》2005,28(3):273-281
Cardiac hypertrophy and left ventricular hypertrophy are known to be substantially controlled by genetic factors. As an experimental model, we undertook genome-wide screens for cardiac mass in F2 populations bred from the stroke-prone spontaneously hypertensive rats (SHRSP) and normal spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) of a Japanese colony. Two F2 cohorts were independently produced: F2(SHRSP x WKY) (110 male and 110 female rats) and F2(SHR x WKY) (151 male rats). The ratio of heart weight to body weight (Hw/Bw) was evaluated at 12 months of age in F2(SHRSP x WKY) after salt-loading for 7 months, and at around 15 weeks of age in F2(SHR x WKY) who had been fed a normal rat chow diet. Subsequent to an initial screen with 251 markers in F2(SHRSP x WKY) male progeny, 170 and 161 markers were selected and characterized in F2(SHRSP x WKY) female progeny and F2(SHR x WKY) male progeny, respectively. Markers from four chromosomal regions showed suggestive or significant linkage to Hw/Bw. The strongest and the most consistent linkage was found in the vicinity of D3Mgh16 on rat chromosome (RNO) 3 (a maximal log of the odds score reached 4.0 to 6.6 across the F2 populations studied). In the other three regions on RNO6, RNO10 and RNO13, the degree of linkage was more prominent in either males or females. These data provide solid evidence for a "principal" RNO3 quantitative trait loci regulating Hw/Bw in SHRSP and SHR, and also suggest the possible presence of sexual dimorphism in regard to genetic susceptibility for cardiac hypertrophy. 相似文献
67.
Accumulation of cholera toxin and GM1 ganglioside in the early endosome of Niemann–Pick C1-deficient cells
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Yuko Sugimoto Haruaki Ninomiya Yuki Ohsaki Katsumi Higaki Joanna P. Davies Yiannis A. Ioannou Kousaku Ohno 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(22):12391-12396
We investigated intracellular trafficking of GM1 ganglioside in Niemann-Pick C1 (NPC1)-deficient Chinese hamster ovary cells [NPC1(-) cells] by using cholera toxin (CT) as a probe. Both the holotoxin and the B subunit (CTB) accumulated in GM1-enriched intracellular vesicles of NPC1(-) cells. CTB-labeled vesicles contained the early endosome marker Rab5 but not lysosome-associated membrane protein 2 and were not labeled with either Texas red-transferrin or Lysotracker, indicating that they represent early endosomes. Similarly, CT accumulated in intracellular vesicles of human NPC fibroblasts that contained both Rab5 and early endosomal antigen 1. CTB accumulation in NPC1(-) cells was abolished by expression of wild-type NPC1 but not by mutant proteins with a mutation either in the NPC domain or the sterol-sensing domain. A part of these mutant NPC1 proteins expressed in NPC1(-) cells was localized on CTB-labeled vesicles. U18666A treatment of "knock in" cells [NPC1(-) cells that stably expressed wild-type NPC1] caused CTB accumulation similar to that in NPC1(-) cells, and a part of wild-type NPC1was localized on CTB-labeled vesicles in drug-treated cells. Finally, CT tracer experiments in NPC1(-) cells revealed retarded excretion of internalized toxin into the culture medium and an increase in the intracellular release of A subunits. In accordance with the latter result, CT was more effective in stimulating cAMP formation in NPC1(-) than in wild-type cells. These results suggest that transport of CT/GM1 complexes from the early endosome to the plasma membrane depends on the function of NPC1, whereas transport to the Golgi apparatus/endoplasmic reticulum does not. 相似文献
68.
OBJECTIVE: Stroke-prone spontaneously hypertensive rats (SHRSP) are known to have sympathetic hyperactivity to various stimuli. In the search for 'intermediate phenotypes' inferring the function of hypertension genes, the present study assessed responsiveness to cold stress in a congenic strain derived from SHRSP/Izm and Wistar-Kyoto/Izm (WKY/Izm). DESIGN: A congenic strain, WKYpch1.0, was established by 10 generations of backcrossing to transfer the chromosomal fragment between D1Wox29 and D1Arb21 of SHRSP to WKY. This fragment covered the 100:1 confidence interval of the quantitative trait locus (QTL) for blood pressure identified in a previous study. Response to cold stress was studied by exposing rats to 4 degrees C for 4 h. Blood pressure was monitored with telemetry. Urine was collected during the exposure, and urinary concentrations of catecholamines were measured by high-performance liquid chromatography. RESULTS: Under the cold stress, urinary excretion of norepinephrine (NE) and vanillylmandelic acid (VMA), as well as the plasma level of NE, was significantly greater in WKYpch1.0 than in WKY. The increase in blood pressure during the cold stress was also greater in WKYpch1.0 than in WKY. Further, neonatal chemical sympathectomy using guanethidine abolished the exaggerated response in blood pressure and in urinary excretion of NE and VMA in WKYpch1.0. CONCLUSION: These results suggested that the QTL region on rat chromosome 1 harbored genes responsible for the exaggerated response of the sympathetic nervous system to the cold stress. The relationship of this with the pathogenesis of hypertension should be elucidated in future studies. 相似文献
69.
Ayumi Hida Misa Imaizumi Benjamin French Waka Ohishi Daisuke Haruta Katsumi Eguchi Hideki Nakamura Atsushi Kawakami 《Medicine》2021,100(24)
Previous studies have suggested that human T-cell leukemia virus type 1 (HTLV-1) might act as a pathogen in rheumatoid arthritis (RA), but epidemiological evidence of an association is scarce. We measured anti-HTLV-1 antibodies among Nagasaki atomic bomb survivors to determine whether HTLV-1 is related to RA and whether radiation exposure is associated with HTLV-1 and RA prevalence.This is a cross-sectional study among atomic bomb survivors who participated in biennial health examinations from 2006 to 2010. Serum levels of anti-HTLV-1 antibodies were measured using a chemiluminescent enzyme immunoassay and confirmed by Western blotting. Association between HTLV-1 and RA was analyzed by a logistic regression model.Of 2091 participants (women 61.5%; median age, 73 years), 215 (10.3%) had anti-HTLV-1 antibodies. HTLV-1 prevalence was higher among women (13.1% vs 5.8%; P < .001). Twenty-two participants (1.1%) were diagnosed with RA. HTLV-1 prevalence among RA participants was significantly higher than that among non-RA participants (27.3% vs 10.1%; P = .020). After adjustment for age, sex, and hepatitis C virus infection, HTLV-1 was significantly associated with prevalent RA (odds ratio, 2.89; 95% confidence interval, 1.06, 7.03). There was no association between radiation dose and either the prevalence of HTLV-1 or RA.This study, among a well-defined group of atomic bomb survivors, suggests that HTLV-1 is associated with RA. 相似文献
70.
Otsubo S Tanabe K Shinmura H Ishikawa N Tokumoto T Hattori M Ito K Nitta K Akiba T Nihei H Toma H 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2004,8(4):299-304
In the present study, we reviewed the effect of post-transplant double filtration plasmapheresis (DFPP) on recurrent focal segmental glomerulosclerosis (FSGS) in the transplanted kidney allograft. Sixteen patients with post-transplant recurrent FSGS were enrolled in this study. Out of 16 patients with recurrent FSGS after transplantation, five did not receive DFPP and lost their grafts, while 11 did receive DFPP and four of these patients lost their grafts. Seven patients were able to maintain normal renal function for an average observation period of 57.1 +/- 40.7 months (range 7-125 months). In five patients who had a significant reduction in urinary protein after DFPP, the urinary protein level decreased from 26.60 +/- 23.05 g/day (range 3.34-62.6 g/day) to 2.95 +/- 3.42 g/day (range 0.02-8.64 g/day) and renal function was maintained. The beneficial effects of DFPP on graft outcome were more likely to occur if the patients experienced a marked drop in urinary excretion. Thus, post-transplant DFPP appears to be effective for reducing urinary protein levels and improving long-term graft survival. With the small numbers in this trial, however, none of the findings were statistically significant. We recommend the use of post-transplant DFPP to prevent the progression of recurrent FSGS. 相似文献