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排序方式: 共有8157条查询结果,搜索用时 437 毫秒
101.
Ilona Kryspin S rensen Eva Kristiansen Alicja Mortensen Gert M. Nicolaisen Jolanda A. H. Wijnands Henk J. van Kranen Coen F. van Kreijl 《Cancer letters》1998,130(1-2):217-225
Data from epidemiological studies suggest that isoflavones in soy may have a protective effect on the development of colon cancer in humans. Therefore, we have investigated whether soy isoflavones will inhibit intestinal tumour development in ApcMin mice. The mice were fed a Western-type high risk diet (high fat, low fibre and calcium) containing two different isolates of soy protein as a protein source. For the control and test groups this resulted in the administration of about 16 and 475 mg of total isoflavones per kg diet, respectively. As a positive control, a third group of mice was administered a low isoflavone diet supplemented with 300 ppm sulindac. No significant differences in the incidence, multiplicity, size and distribution of intestinal tumours were observed between Min mice fed low and high isoflavone-containing diets. However, a clear reduction in the number of small intestinal tumours was observed for the sulindac diet. Thus, in contrast to epidemiological studies, our results demonstrate that high amounts of soy isoflavones present in a Western-type high risk diet do not protect against intestinal tumour development in a relevant animal model such as the Min mice. 相似文献
102.
Alexandros Papanikolaou Qian-Shu Wang Don A. Delker Daniel W. Rosenberg 《Cancer letters》1998,130(1-2):29-34
Azoxymethane (AOM) is an organotropic colon carcinogen that is commonly used to induce colon tumors in rodents. Unlike its parent compound, 1,2-dimethylhydrazine (DMH), a tumor susceptibility phenotype in inbred mice with respect to AOM has not been established. Thus, this study was undertaken to determine whether genetic susceptibility extends to this carcinogen. SWR/J, A/J (both susceptible to DMH carcinogenesis) and AKR/J (resistant) mice were treated with 10 mg/kg AOM i.p. once a week for 8 weeks. Twenty-five weeks after the initial injection, tumor yield was determined. With a single exception, only SWR/J and A/J mice developed tumors, with a distribution that was limited to the distal colon (16.3±1.1 and 36.4±2.4, respectively). The formation of aberrant crypt foci (ACF), putative preneoplastic lesions, was also assessed in whole-mount colons using Methylene Blue staining. Consistent with tumor multiplicity, the total number of ACF was highest in A/J mice, followed by SWR/J mice. In addition, A/J mice had a significantly greater number of large ACF (five or more crypts per foci) than the other strains. Despite the absence of colon tumors, however, AKR/J mice did develop a significant number of ACF. This finding suggests that ACF in resistant mice are persistent but do not progress to tumors. 相似文献
103.
Hidehiro Nomura Yutaka Takahashi Masayoshi Mai 《International journal of clinical oncology / Japan Society of Clinical Oncology》1998,3(2):117-120
A 53-year-old woman had shown repeated, partial responses to chemotherapy for large, multiple liver metastases of sigmoid
colon cancer. After a partial response to 5-fluorouracil plus leucovorin therapy, an 89.7% reduction of the 5-fluorouracil-resistant
metastatic tumor was achieved by giving CPT-11 (irinotecan) at a dose of 100 mg/body per week. We suggest that CPT-11 should
be recommended as an effective second-line treatment for unresectable liver metastases of colon cancer, after 5-fluorouracil-based
chemotherapy. 相似文献
104.
G Gatta J Faivre R Capocaccia M Ponz de Leon EUROCARE Working Group 《European journal of cancer (Oxford, England : 1990)》1998,34(14):2176-2183
This study concerns the survival of European patients diagnosed between 1978 and 1989 with colorectal cancer. Variations in survival in relation to age, country and period of diagnosis were examined. Data from the EUROCARE study were supplied by population-based cancer registries in 17 countries to a common protocol. Five years after diagnosis, relative survival rates were 47 and 43% for cancers of the colon and rectum, respectively. Survival decreased with increasing age: the relative risk of dying for the oldest patients (75+) was 1.39 for rectum and 1.54 for colon compared with the youngest patients (15-44 years). In 1985-1989 survival from colorectal cancer differed significantly between different European countries: the Nordic countries (Denmark excluded), The Netherlands, Switzerland, France and Austria were characterised by high survival, whilst Eastern European countries, the U.K. and Denmark were characterised by low survival. There was a general improvement in survival over the period 1978-1989: from 40 to 48% for colon cancer and 38 to 46% for rectal cancer. For neither cancer site did between-country survival differences narrow over the study period. Intercountry and time differences in survival differences are probably related to stage at diagnosis and postoperative mortality. 相似文献
105.
本室以往的研究表明,用腺病毒作为载体将大肠杆菌胞嘧啶脱氨酶(CD)基因与小鼠淋巴细胞趋化因子(Itn)基因联合体内转染,具有显著的抗肿瘤效应.本文对其免疫机理进行了进一步研究,发现CT26结肠腺癌细胞体外经过CD/Ltn基因转染并给予前体药物5-FC后,CT26结肠腺癌细胞表达CD80和CD54分子明显增加,提示经CD自杀基因和Ltn基因联转移后,肿瘤细胞免疫原性增加.荷瘤小鼠体内经联合治疗后,小鼠脾细胞分泌IL-2和IFN-γ明显增加.体内用抗CD4、CD8抗体阻断实验研究结果的表明,联合应用自杀基因和Ltn基因治疗主要通过诱导CD8~ T细胞发挥抗肿瘤作用. 相似文献
106.
Nester C 《Gait & posture》2000,12(3):251-256
The purpose of this study was to test the clinical hypothesis that the magnitude and temporal characteristics of rearfoot complex motion are closely correlated with those of the transverse plane motion at the knee and hip. Twenty subjects underwent kinematic assessment during walking at 108 steps/minute. The transverse plane rotation of the leg relative to the foot was used to indicate rearfoot complex pronation and supination. Taking into account errors inherent in kinematic assessment involving skin mounted markers, it is unlikely that a correlation exists between the range of internal leg rotation during the contact phase and the total range of transverse plane leg rotation during gait and the corresponding values for the transverse plane motion at the knee and hip. Correlation tests were performed to assess the temporal characteristics of the motions at the joints that showed that there was no correlation between the transverse plane motion in the rearfoot complex, knee and hip. Thus the hypothesis that the magnitude and temporal characteristics of rearfoot complex motion are closely correlated with the transverse plane motion at the knee and hip was rejected. 相似文献
107.
Bacterial adherence in a rat bladder augmentation model: ileocystoplasty versus colocystoplasty 总被引:2,自引:0,他引:2
Sakai Y Fujisawa M Nakano Y Miyazaki S Arakawa S Kamidono S 《The Journal of urology》2000,164(6):2104-2107
PURPOSE: Various intestinal segments are used to reconstruct the urinary tract. For unclear reasons asymptomatic chronic bacteriuria is common in patients treated with reconstruction. We compared bacterial adherence in ileum, colon and bladder in rats with ileal and colonic bladder augmentation. MATERIALS AND METHODS: Bladder augmentation using ileum or colon was performed in 8-week-old rats. After 3 months urinary pH was measured and urine was cultured. Urovirulence factors of Escherichia coli aspirated from the augmented bladders were detected by polymerase chain reaction. In rats with negative urine culture after augmentation experimental cystitis was induced by the transurethral inoculation of E. coli C5, with type I pili and aerobactin or E. coli C92 with type I pili, P fimbriae and aerobactin at a concentration of 10(5) colony forming units per 0.3 ml. After 14 days we counted the colony forming units per cm.(2) of bladder and cm.(2) of intestinal augmentation tissue. RESULTS: When cultures were negative, mean urinary pH plus or minus standard deviation for ileocystoplasty (7.35 +/- 0.33) was significantly higher than that for colocystoplasty (6.80 +/- 0.45) or in controls (6.67 +/- 0.30). Bacterial colonization occurred in 60 of 96 ileocystoplasties (62.5%) and 36 of 68 colocystoplasties (52.9%). All 32 E. coli strains aspirated from ileocystoplasties had type I pili. In colocystoplasties 14 strains had type I pili, 4 had P fimbriae and type I pili, and 1 had no virulence factor. In experimental cystitis in the ileal patch and bladder there were 10(3.2) to 10(6.2) (log mean 4.9) and 10(1.1) to 10(5.1) (log mean 3.5) colony forming units of E. coli C5, respectively. In the colonic patch and bladder there were 10(2.2) to 10(6.2) (log mean 3.9) and 10(2.1) to 10(5.1) (log mean 3.7) colony forming units of E. coli C5, respectively. In the ileal patch and bladder versus the colonic patch and bladder there were 10(3.2) to 10(6.2) (log mean 5.0) and 10(3.1) to 10(6.1) (log mean 4.5) versus 10(3.2) to 10(6.2) (log mean 4.3) and 10(2.1) to 10(6.1) (log mean 3.8) colony forming units of E. coli C92, respectively. E. coli C5 adhered to more ileum than bladder, while bacterial adherence did not differ for colon and bladder. Adherence of E. coli C92 did not differ significantly in bladder and implanted ileum or colon. CONCLUSIONS: The colonic segment offers more resistance to E. coli than the ileal segment in urinary diversion. 相似文献
108.
109.
110.
目的探讨大肠癌并急性肠梗阻的外科治疗方法及效果。方法回顾性分析1998年10月~2003年10月45例大肠癌并发急性肠梗阻行一期切除吻合的临床资料。结果术后肺部感染2例,伤口感染6例,无吻合口瘘37例,并发症总发生率17.8%。结论一期切除吻合手术治疗大肠癌并急性肠梗阻是可行的,而合理选择手术方式,正确的术中操作和围手术期处理对提高疗效、改善患者生活质量有所裨益。 相似文献