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排序方式: 共有2708条查询结果,搜索用时 31 毫秒
101.
Munira Akhter Yoshikazu Nishino Naoki Nakaya Kayoko Kurashima Yuki Sato Shinichi Kuriyama Yoshitaka Tsubono Ichiro Tsuji 《European journal of cancer prevention》2007,16(2):102-107
The association between cigarette smoking and the risk of colorectal cancer remains controversial. We examined this association using a population-based prospective cohort study in Miyagi, Japan. In 1990, we delivered a self-administered questionnaire on cigarette smoking and other health habits to 25 279 men who were 40-64 years of age and lived in 14 municipalities of Miyagi Prefecture. A total of 22 836 men responded (90.3% response rate). During 7 years of follow-up (158 376 person-years), we identified 188 patients of colorectal cancer. Relative risks and 95% confidence intervals were estimated by the Cox proportional-hazards regression analysis with adjustment for potential confounders. The multivariate-adjusted relative risks (95% confidence interval) of colorectal cancer for past smokers and current smokers compared with those who had never smoked were 1.73 (1.04-2.87) and 1.47 (0.93-2.34), respectively. Among current smokers, both a higher number of cigarettes smoked per day and an earlier age at which smoking had started were associated with a significant linear increase in risk (P for trend <0.05). Our findings are consistent with the hypothesis that cigarette smoking is associated with a higher risk of colorectal cancer in men. 相似文献
102.
BACKGROUND: Short-term estrogen administration improves vasodilation and has been shown to improve exercise capacity. However, it is unknown whether long-term estrogen replacement therapy is associated with improved exercise capacity in postmenopausal women without known coronary artery disease. METHODS AND RESULTS: We studied 248 postmenopausal women without known coronary artery disease (mean age 63.5 years); 158 (64%) were current or past hormone replacement therapy (HRT) users and 108 (44%) were current users of HRT. Attributes potentially affecting exercise capacity and cardiac risk factors were carefully measured. These included duration of estrogen replacement therapy, all variables in the Framingham risk index, physical activity level, body mass index, waist-to-hip ratio, presence of osteoporosis, and family history of heart disease. We measured maximal oxygen uptake (MVO (2)) and anaerobic threshold as objective markers of exercise capacity. The relation between exercise capacity and use of HRT was analyzed with the use of logistic regression, controlling for confounding variables. We found that fitness, as measured by MVO (2) and anaerobic threshold, was significantly greater in women who had used HRT currently or in the past compared with women who had never used HRT. This difference in fitness was not confounded by age or physical activity level. CONCLUSIONS: Estrogen replacement therapy is associated with increased exercise capacity as measured by MVO (2) and anaerobic threshold in postmenopausal women without coronary artery disease. This finding is consistent with the beneficial effect of short-term estrogen administration on improved endothelium-dependent and endothelium-independent vasodilation. 相似文献
103.
M. Hino M. Inaba H. Goto Y. Nishizawa N. Tatsumi T. Nishino H. Morii 《British journal of cancer》1996,73(1):119-123
Hepatocyte growth factor (HGF) has been known as a multiple function factor, which also stimulates early haematopoiesis. In this study, we found that HGF was expressed at both the RNA and protein levels in acute myeloid leukaemia (AML) and chronic myeloid leukaemia (CML). In patients with AML (n = 20) and CML (n = 5), bone marrow plasma HGF concentrations were 20.44 +/- 6.26 (mean +/- s.e.) ng ml-1 and 7.17 +/- 0.53 ng ml-1 respectively. These were significantly higher (P < 0.01) than the value for normal subjects (n = 26): mean 0.92 +/- 0.09 ng ml-1. Constitutive HGF production was observed in freshly prepared leukaemic blast cells from three patients with high HGF levels of bone marrow plasma. Expression of HGF mRNA was correlated with bone marrow plasma HGF levels. After complete remission was obtained in six patients, bone marrow plasma HGF levels were significantly decreased. In contrast, the HGF mRNA was less abundantly expressed in acute lymphoid leukaemia (ALL). In patients with ALL (n = 5), bone marrow plasma HGF concentration (0.69 +/- 0.14 ng ml-1) remained low within the value for normal subjects. These results suggest that some populations of myeloid lineage cells have the ability to produce HGF. 相似文献
104.
Colombo D Compostella F Ronchetti F Scala A Toma L Tokuda H Nishino H 《European journal of medicinal chemistry》2000,35(12):1109-1113
The in vitro anti-tumor promoting effect of monohexanoates of 2-O-alpha-D-gluco- and galactopyranosyl-sn-glycerol on the 12-O-tetradecanoylphorbol-13-acetate (TPA) induced Epstein-Barr virus early antigen (EBV-EA) activation was evaluated and compared to the potencies of the corresponding beta-anomers. The results show that the inversion of the anomeric configuration from beta to alpha does not seem to significantly influence the activity, which is present, as for the beta-anomers, even at 1x10 mol ratio without any cytotoxicity. 相似文献
105.
Hirokazu Tsukahara M.D. Tadahiko Sakaguchi M.D. Izuru Mitsuyoshi M.D. Hitoo Fukuhara M.D. Shuhei Hayashi M.D. Katsuji Nakamura M.D. 《Pediatrics international》1988,30(4):520-525
Biochemical and radiographic abnormalities linked with phosphorus deficiency syndrome (PDS) developed in two very low birthweight (VLBW) infants fed exclusively with human milk. By increasing phosphorus (P) and calcium (Ca) intakes with the introduction of a specialized premature formula, osteopenia or rickets, as well as hypophosphatemia, hypo-phosphaturia and increased serum alkaline phosphatase levels improved in both patients. We speculated that all VLBW infants who are being fed exclusively with human milk should be monitored for PDS and that if PDS develops, supplementation of human milk with both P and Ca appears to be necessary for its treatment. 相似文献
106.
Y Tanaka G Ueda M Inoue K Hiramatsu Y Inoue J Saito T Nishino M Yamasaki K Kurachi T Mori 《Nippon Sanka Fujinka Gakkai zasshi》1984,36(1):67-71
Mucinous tumors of the ovary are generally considered to have a dual origin in histogenesis. Teratomatous elements, however, have recently been reported as appearing in a process of intestinal metaplasia. Malignant transformation has also been felt to occur through intestinalization. To clarify the matter, the relationships among morphological changes in intestinalization, carcinoembryonic antigen and mucus antigens named IMA and M1, which were isolated from intestinal mucosa and ovarian mucinous cyst fluid respectively, were studied in 4 benign, 8 borderline and 6 malignant mucinous tumors of the ovary. Intestinal type and goblet- like cells were sparse, if any, in benign tumors, but conspicuous in borderline and malignant ones. Carcinoembryonic antigen was located in the glycocalyx of intestinal type cells in the benign tumors, but distributed over the entire cytoplasm increasingly with malignancy. These findings lend support to the theory that malignant transformation may occur through intestinal metaplasia in mucous tumors. M1 was positive in many cells of all mucinous tumors, but IMA was shown in some goblet-like cells of a few tumors, regardless of malignancy or the presence of argyrophil cells. These phenomena could be best understood by postulating that IMA was located in the teratomatous intestinal goblet cells of the tumors. 相似文献
107.
Hypo-estrogenic state induces the increased bone turnover finally into osteoporosis. Most typical case of hypo-estrogenic bone metabolism is that of postmenopausal women. We pay attention to other bone metabolism in hypo-estrogenic state women; (1) Amenorrhea patients in young women; (2) Oophorectomized young women; (3) Patients on GnRH analogue therapy. These patients should be evaluated their bone metabolism carefully. It is also important to prevent their bone loss with hormone replacement therapy. 相似文献
108.
Ukiya M Akihisa T Tokuda H Hirano M Oshikubo M Nobukuni Y Kimura Y Tai T Kondo S Nishino H 《Journal of natural products》2002,65(4):462-465
The structures of two novel 3,4-seco-lanostane-type triterpenes isolated from the sclerotium of Poria cocos were established to be 16alpha-hydroxy-3,4-seco-lanosta-4(28),8,24-triene-3,21-dioic acid (1; poricoic acid G) and 16alpha-hydroxy-3,4-seco-24-methyllanosta-4(28),8,24(24(1))-triene-3,21-dioic acid (2; poricoic acid H) on the basis of spectroscopic methods. These two, and eight other known compounds isolated from the sclerotium, poricoic acid B (3), poricoic acid A (4), tumulosic acid (5), dehydrotumulosic acid (6), 3-epidehydrotumulosic acid (7), polyporenic acid C (8), 25-hydroxy-3-epidehydrotumulosic acid (9), and dehydroabietic acid methyl ester (10), showed potent inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Evaluation of the cytotoxicity of compounds 1 and 4 against human cancer cell lines revealed that 1 was significantly cytotoxic to leukemia HL-60 cells [GI(50) (concentration that yields 50% growth) value 39.3 nM], although it showed only moderate cytotoxicity to the other cells. Compound 4 exhibited moderate cytotoxicity to all of the cancer cell lines tested. 相似文献
109.
Chen DF Zhang SX Kozuka M Sun QZ Feng J Wang Q Mukainaka T Nobukuni Y Tokuda H Nishino H Wang HK Morris-Natschke SL Lee KH 《Journal of natural products》2002,65(9):1242-1245
Two new lignans, interiotherins C (1) and D (2), together with the known compounds interiorin (3), heteroclitin F (4), neokadsuranin (5), heteroclitin D (6), kadsurin (7), gomisin A (8), schisandrin C (9), interiotherin A (10), angeloylgomisin R (11), gomisin G (12), interiotherin B (13), and gomisin C (14), were isolated from the stems of Kadsura interior. The structures and stereochemistries of the new compounds were determined from mass, CD, and NMR spectral data. Fourteen neolignans were screened as potential antitumor promoters by examining their ability to inhibit Epstein-Barr virus early antigen (EBV-EA) activation (induced by 12-O-tetradecanoylphorbol-13-acetate) in Raji cells. Neokadsuranin (5) and schisandrin C (9) were the most potent compounds. These data suggest that some neolignans might be valuable antitumor promoters or chemopreventors. 相似文献
110.
Chang S Ishikawa T Nonaka I Tsukamoto H Saito M Ban K Wada I Sugie K Nishino I 《No to hattatsu. Brain and development》2003,35(2):159-164
We report three patients with sporadic merosin-positive congenital muscular dystrophy (CMD) with torticollis and/or developmental dislocation of the hip in early childhood. Diagnosis of merosin-positive CMD was based on their clinical and dystrophic muscle biopsy findings. At the age 13 months, patient 1 was found to have developmental dislocation of both hips, which was surgically treated at 5 years. Patient 2 had severe torticollis and contracture of both hip joints which had been present since the neonatal period, and underwent repair of the torticollis at 2 years. Patient 3 was found to have developmental dislocation of the left hip at one month of age. Although she had generalized muscle hypotonia she learned to walk at 23 months. She had no facial muscle involvement nor contracture of joints, but had hyperlaxity of distal joints. Her muscle biopsy showed complete collagen VI deficiency immunohistochemically. In contrast to merosin-deficient CMD, merosin-positive CMD appears to be a group of heterogeneous diseases. Since collagen VI was reported to be defective in Ullrich's disease, patient 3 may be diagnosed as having Ullrich's disease but had no typical clinical characteristics of the disease. Further study is needed to identify the pathogenetic mechanism of congenital muscular dystrophy with early joint abnormalities to determine whether there is a primary abnormality of the connective tissue including collagen VI. 相似文献