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排序方式: 共有1409条查询结果,搜索用时 15 毫秒
71.
Kotake H Sekikawa A Tokita Y Ishigaki Y Oikawa S 《Journal of atherosclerosis and thrombosis》2002,9(5):207-212
We investigated the effects of HMG-CoA reductase inhibitors (statins) on the activity and concentration of plasma cholesterol ester transfer protein (CETP) in 30 hypercholesterolemic patients.Patients were divided into three groups according to TaqIB polymorphism of the CETP gene.The activity (158 +/- 23% control, mean +/- SEM) and concentration (4.1 +/- 1.0 mg/l) of plasma CETP were significantly (p < 0.005) higher in the subjects with the B1B1 genotype than B2B2 genotype (106 +/- 25% and 2.5 +/- 1.1 mg/l, respectively).Plasma CETP activity and concentration levels in the B1B2 group were intermediate between those of the B1B1 and B2B2 groups, and significantly (p < 0.05) low compared with the B1B1 group.Both the activity and concentration of plasma CETP were positively correlated with the LDL-cholesterol concentration (r = 0.608, p < 0.0005 and r = 0.552, p < 0.005, respectively).The administration of statins significantly reduced not only the activity (p < 0.01) but also the concentration (p < 0.05) of plasma CETP in hypercholesterolemic patients. Taken together, we confirmed that statins would be effective in increasing HDL levels in Japanese B1B1 carriers, because of a lower concentration of HDL cholesterol and higher level of plasma CETP compared to the other genotypes.The genetic variation in the CETP gene may be one important factor in designing better treatments. 相似文献
72.
A case of clinically multifocal renal cell carcinoma 总被引:2,自引:0,他引:2
Kiuchi H Kinouchi T Shiba M Maeda O Saiki S Kuroda M Usami M Kotake T 《Hinyokika kiyo. Acta urologica Japonica》2001,47(3):179-181
A 61-year-old woman was diagnosed with a renal tumor of the left kidney by ultrasound sonography during a health check-up. Computerized tomography (CT) and colored Doppler ultrasound sonography demonstrated two hypervascular tumors as typical renal cell carcinomas. A radically nephrectomized specimen was step-sectioned. Four tumor nodules were detected macroscopically, and 47 small nodules were detected microscopically, showing the clear cell type and alveolar growth pattern. Then all nodules including the 47 small nodules were diagnosed renal cell carcinoma. 相似文献
73.
Differences in the p53 gene mutational spectra of prostate cancers between Japan and Western countries 总被引:4,自引:1,他引:4
Watanabe M; Fukutome K; Shiraishi T; Murata M; Kawamura J; Shimazaki J; Kotake T; Yatani R 《Carcinogenesis》1997,18(7):1355-1358
Mutations of the p53 gene are related to development of human cancers and
their frequencies and spectra, the latter representing fingerprints left by
carcinogens, provide information about the molecular epidemiology of the
disease. Prostate cancer is the most common neoplasm in American males and
although its incidence is still relatively low in Japanese people, it has
recently been increasing with the westernization of life style. To assess
the frequency and spectrum of p53 gene mutations in Japanese prostate
cancers, we examined a series of 90 lesions using polymerase chain reaction
(PCR)-single- strand conformation polymorphism (SSCP) analysis. The
patients' mean age was 69.3 years (range 57-87). Of the total, six were
well-, 34 moderately- and 50 poorly-differentiated adenocarcinomas, and the
median Gleason score was 7.9. Eleven of the 90 cases (12%) had mutations in
exons 2-11 of the p53 gene: none of the five clinical- stage A, one of 25
stage B (4%), three of 35 stage C (9%) and seven of 25 stage D (28%)
cancers. The correlation with an advanced stage was statistically
significant. One insertion and 10 base pair substitutions were encountered,
comprising six transversions (55%) and four transitions (36%). Two of the
latter involved methylated cytosine- guanine (CpG). These 11 mutations were
combined with 18 other mutations in previous reports concerning Japanese
prostate cancers to facilitate comparison of the p53 gene mutational
spectrum with those reported for American and European prostate cancers. In
the latter, 61% were transitions and 33% were transversions. The greater
proportion of transversions in the Japanese population suggests that there
are different factors responsible for carcinogenesis of the prostate glands
in the various countries.
相似文献
74.
5-fluorouracil sensitivity and dihydropyrimidine dehydrogenase activity in advanced gastric cancer 总被引:2,自引:0,他引:2
Inada T Ogata Y Kubota T Tomikawa M Yamamoto S Andoh J Ozawa I Hishinuma S Shimizu H Kotake K 《Anticancer research》2000,20(4):2457-2462
BACKGROUND: Dihydropyrimidine dehydrogenase (DPD) is the rate-limiting enzyme of 5-fluorouracil (5-FU) catabolism. Several studies have demonstrated the clinical importance of DPD in cancer patients, suggesting that the efficacy of 5-FU may be related to DPD activity in tumor tissue. In the present study, DPD activity and chemosensitivity to 5-FU were evaluated in advanced gastric cancer. Materials and METHODS: Thirty-four gastric cancers from 32 patients were studied and chemosensitivity to 5-FU was evaluated by histoculture drug response assay. RESULTS AND CONCLUSION: DPD activity and tumor inhibition of 5-FU among all cases showed no significant correlation, but among 14 histologically differentiated cases significant correlation was observed. DPD activity may be useful in determining the 5-FU sensitivity of differentiated gastric cancer. 相似文献
75.
OBJECTIVE: The pacemaker current in cardiac Purkinje fibres has been attributed to either a decrease in potassium conductance or an increase in a non-specific (Na-K) conductance. The former mechanism would be associated with an increase in membrane resistance (Rm) and the latter with a decrease in Rm. The aim of this study was to obtain evidence in support of one or other mechanism by measuring Rm during the pacemaker current (Idd) under conditions where there is a small or no extracellular potassium depletion. METHODS: Hearts were obtained from anaesthetised sheep and thin strands of ventricular Purkinje fibres were shortened to less than or equal to 1.6 mm. Purkinje fibres were voltage clamped to potentials positive and negative to the potassium equilibrium potential (EK) using a two microelectrode technique. Small current pulses were superimposed on Idd to measure Rm changes. Procedures were used that decrease either the background potassium current IKl or Idd in order to dissect changes in Rm due to K depletion from those due to Idd. RESULTS: Rm increased during Idd, whether the pacemaker current increased or decreased as a function of time. Increasing [K]o from 2.7 to 5.4 mmol.litre-1 decreased Rm and during hyperpolarising steps increased the instantaneous current but did not change Idd amplitude. In 2.7 mmol.litre-1 K, caesium (Cs, 2 mmol.litre-1) increased the holding current (Ih), had little effect on the instantaneous current, and eliminated Idd and associated Rm changes. In 5.4 and 10.8 mmol.litre-1 K, Cs increased Ih and decreased Idd amplitude and in 10.8 mmol.litre-1 K Cs decreased the instantaneous current on hyperpolarisation. If the current was reversed, Cs decreased but did not abolish it. In normal [K]o, barium (Ba, 0.05-0.5 mmol.litre-1) increased Ih and Rm, reduced the instantaneous current but did not increase Idd amplitude. In high [K]o, Ba instead increased the amplitude and rate of development of Idd. When Cs was applied in the presence of Ba, Idd was reduced or eliminated depending on [K]o. CONCLUSIONS: The changes in membrane resistance during the pacemaker current cannot be accounted for by K depletion and suggest that in the range of diastolic depolarisation the pacemaker current results predominantly from a time dependent decrease in K conductance. 相似文献
76.
We examined the effect of deprenyl, a promising drug for the therapy of Parkinson's disease on the formation of a parkinsonism-inducing compound, 1-benzyl-1,2,3,4-tetrahydroisoquinoline (1BnTIQ). The 1BnTIQ content was significantly decreased in the brain of deprenyl-treated mouse in vivo, and deprenyl also inhibited 1BnTIQ formation from phenethylamine by a mouse brain homogenate supernatant in vitro. In vivo, the content of a parkinsonism-preventing compound, 1-methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ) was slightly increased in mice injected with deprenyl. The marked decrease of the ratio of 1BnTIQ to 1MeTIQ might play a role in the clinical effect of deprenyl. 相似文献
77.
M Ikeda T Hosotani K Kurimoto T Mori T Ueda Y Kotake B Sakakibara 《Journal of nutritional science and vitaminology》1979,25(3):131-139
The differences of the metabolism related to vitamin B6-dependent enzymes were investigated using germ-free and conventional rats. There was a significant difference in the boyd weight gain between vitamin B6-deficient germ-free and conventional rats after about 30 days of the experiment, and the body weight gain was much less in the deficient germ-free rats than in the deficient conventional ones. Urinary excretion of xanthurenic acid was higher in the deficient germ-free rats than in the deficient conventional ones after 18 days. There was a significant difference in the activities of kynurenine aminotransferase in mitochondrial fractions of germ-free rats, but not in mitochondrial fractions of conventional ones. The activities of aspartate and alanine aminotransferases, with or without pyridoxal phosphate, significantly decreased in the deficient germ-free rats, but not in the deficient conventional ones. These findings indicate that the degree of vitamin B6 deficiency was more severe in the deficient germ-free rats than in the deficient conventional ones, and also suggest that intestinal microflora may have some effects on vitamin B6-deficient conventional rats. 相似文献
78.
Jee CD Lee HS Bae SI Yang HK Lee YM Rho MS Kim WH 《International journal of oncology》2005,26(5):1265-1271
The caspases are a family of aspartic acid-specific proteases that fulfill varied and often critical roles in mammalian apoptosis or in the proteolytic activation of cytokines. Caspase-1 (interleukin-1beta-converting enzyme) is a member of the cysteine protease family, which cleaves target proteins following aspartic acid residues. We investigated caspase-1 expression in stomach cancer, tissues and cell lines. Of 301 consecutive gastric carcinomas, 58 cases (19.3%) showed the expressional loss of caspase-1. Loss of caspase-1 expression was significantly associated with pTNM stage (p=0.03), lymph node metastasis (p=0.01) and patient survival (p<0.01). Caspase-1 expression was also significantly correlated in an inverse manner with p53 expression (p<0.01). Among the 11 gastric cancer cell lines examined, three cell lines showed loss of expression at the protein and mRNA levels. On treatment with 5-aza-2'-deoxycytidine (5-aza-C), and/or trichostatin A (TSA), all three cell lines re-expressed caspase-1 mRNA. The above findings suggest that epigenetic events such as DNA methylation and histone deacetylation play important roles in the regulation of caspase-1, and that loss of caspase-1 expression is associated with poor survival in gastric carcinoma. 相似文献
79.
Saeki M Saito Y Jinno H Sai K Hachisuka A Kaniwa N Ozawa S Kawamoto M Kamatani N Shirao K Minami H Ohtsu A Yoshida T Saijo N Komamura K Kotake T Morishita H Kamakura S Kitakaze M Tomoike H Sawada J 《Drug metabolism and pharmacokinetics》2005,20(2):144-151
Nineteen genetic variations, including 11 novel ones, were found in exon 1 and its flanking region of the UDP-glucuronosyltransferase (UGT) 1A4 gene from 256 Japanese subjects, consisting of 60 healthy volunteers, 88 cancer patients and 108 arrhythmic patients. These variations include -217T>G and -36G>A in the 5'-flanking region, 30G>A (P10P), 127delA (43fsX22; frame-shift from codon 43 resulting in the termination at the 22nd codon, codon 65), 175delG (59fsX6), 271C>T (R91C), 325A>G (R109G), and 357T>C (N119N) in exon 1, and IVS1+1G>T, IVS1+98A>G and IVS1+101G>T in the following intron. Among them, 127delA and 175delG can confer early termination of translation, resulting in an immature protein that probably lacks enzymatic activity. Variation IVS1+1G>T is located at a splice donor site and thus may lead to aberrant splicing. Since we did not find any significant differences in the frequencies of all the variations among the three subject groups, the data were analyzed as one group. The allele frequencies of the novel variations were 0.006 for IVS1+101G>T, 0.004 for 30G>A (P10P) and 357T>C (N119N), and 0.002 for the 8 other variations. In addition, the two known nonsynonymous single nucleotide polymorphisms (SNPs), 31C>T (R11W) and 142T>G (L48V), were found at 0.012 and 0.129 frequencies, respectively. The SNP 70C>A (P24T), mostly linked with 142T>G (L48V) in German Caucasians, was not detected in this study. Sixteen haplotypes were identified or inferred, and some haplotypes were confirmed by cloning and sequencing. It was shown that most of 142T>G (L48V) was linked with -219C>T, -163G>A, 448T>C (L150L), 804G>A (P268P), and IVS1+43C>T, comprising haplotype *3a; haplotype *4a harbors 31C>T (R11W); 127delA (43fsX22) and 142T>G (L48V) were linked (haplotype *5a); 175delG (59fsX6) was linked with 325A>G (R109G) (*6a haplotype); and -219C>T, -163G>A, 142T>G (L48V), 271C>T (R91C), 448T>C (L150L), 804G>A (P268P), and IVS1+43C>T comprised haplotype *7a. Our results provide fundamental and useful information for genotyping UGT1A4 in the Japanese and probably Asian populations. 相似文献
80.
Counting the dead and what they died from: an assessment of the global status of cause of death data 总被引:13,自引:0,他引:13
Mathers CD Fat DM Inoue M Rao C Lopez AD 《Bulletin of the World Health Organization》2005,83(3):171-177
OBJECTIVE: We sought to assess the current status of global data on death registration and to examine several indicators of data completeness and quality. METHODS: We summarized the availability of death registration data by year and country. Indicators of data quality were assessed for each country and included the timeliness, completeness and coverage of registration and the proportion of deaths assigned to ill-defined causes. FINDINGS: At the end of 2003 data on death registration were available from 115 countries, although they were essentially complete for only 64 countries. Coverage of death registration varies from close to 100% in the WHO European Region to less than 10% in the African Region. Only 23 countries have data that are more than 90% complete, where ill-defined causes account for less than 10% of total of causes of death, and where ICD-9 or ICD-10 codes are used. There are 28 countries where less than 70% of the data are complete or where ill-defined codes are assigned to more than 20% of deaths. Twelve high-income countries in western Europe are included among the 55 countries with intermediate-quality data. CONCLUSION: Few countries have good-quality data on mortality that can be used to adequately support policy development and implementation. There is an urgent need for countries to implement death registration systems, even if only through sample registration, or enhance their existing systems in order to rapidly improve knowledge about the most basic of health statistics: who dies from what? 相似文献