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Rao  CV; Chou  D; Simi  B; Ku  H; Reddy  BS 《Carcinogenesis》1998,19(10):1815-1819
The present experiments were aimed at developing novel dietary fibers to aid in reduction of colon cancer risk. We assessed the effects of coffee (non-fiber fraction), coffee fiber (arabino-galactose polymer) and inulin (oligo-fructose) in male F344 rats using formation of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in the colon as the measure of preventive efficacy (or lack of such). At 5 weeks of age, groups of rats were fed the AIN-76A (control) and experimental diets that contained 1% coffee, 10% coffee fiber, 10% inulin, 10% pectin (positive control for fiber) or 200 p.p.m. piroxicam (a known ACF inhibitor). At 7 weeks of age, all animals were s.c injected with AOM (15 mg/kg body wt) once weekly for 2 weeks. All rats were killed 8 weeks after the last AOM injection and ACF were counted. The contents of the cecum were analyzed for bacterial beta-glucuronidase activity and short-chain fatty acids (SCFAs). Dietary administration of coffee fiber significantly suppressed AOM-induction of colonic ACF, in terms of total number, as well as crypt multiplicity and number of ACF/cm2 colon (P < 0.01-0.001). Inulin diet had no significant effect on total ACF, but had reduced the number of ACF/cm2 (P < 0.05). Whereas coffee had no effect on ACF formation, 10% pectin diet and 200 p.p.m. piroxicam significantly suppressed colonic ACF (P < 0.001) as had been expected. A significant reduction of cecal beta-glucuronidase activity was observed in the rats fed coffee, coffee fiber and pectin diets. Further, coffee fiber, inulin and pectin increased cecal SCFA levels 3- to 5-fold. These results suggest that coffee fiber can prevent colon cancer risk. Further studies are warranted to determine the full potential of this fiber in pre-clinical efficacy studies.   相似文献   
64.
OBJECTIVE: To assess the natural history of respiratory symptoms not labelled as asthma in primary schoolchildren. DESIGN: Repeat questionnaire survey of subgroups identified from a previous questionnaire survey after a two year delay. SUBJECTS: The original population of 5321 Sheffield children aged 8-9 years yielded 4406 completed questionnaires in 1991(82.8%). After excluding children with a label of asthma, there were 370 children with current wheeze, 129 children with frequent nocturnal cough, and a random sample of 222 children with minor cough symptoms and 124 asymptomatic children. RESULTS: Response rates in the four groups were 233 (63.0%), 77 (59.7%), 160 (72.1%), and 90 (72.6%) respectively. Of those who initially wheezed, 114 (48.9%) had stopped wheezing and 42 (18.0%) had been labelled as having asthma. Those with more frequent wheezing episodes (p < 0.02) and a personal history of hay fever (p < 0.01) in 1991 were more likely to retain their wheezy symptoms. In the children with frequent nocturnal cough in 1991, 20.1% had developed wheezing, 42.9% had a reduced frequency of nocturnal coughing, and 14.2% had stopped coughing altogether two years later. One sixth had been labelled as having asthma. Children with nocturnal cough were more likely to develop wheezing if they had a family history of atopy (p = 0.02). Only 3.8% and 3.3% of those with minimal cough and no symptoms respectively in 1991 had developed wheeze by 1993 (1.9% and 1.0% labelled as asthma). CONCLUSIONS: Most unlabelled recurrent respiratory symptoms in 8-10 year olds tend to improve. Unlabelled children who have persistent symptoms have other features such as frequent wheezing attacks and a family or personal history of atopy. If a screening questionnaire were to be used to identify such children, a combination of questions should be employed.  相似文献   
65.
Twelve serum samples from French blood donors that were uniformly reactive in tests for antibody to human immunodeficiency virus type 2 (anti-HIV-2) also were reactive in 92 to 100 percent of tests with three anti-HIV type 1 (anti-HIV-1) enzyme-linked immunoassays currently in widespread use for donor screening in the United States. Supplemental tests for anti-HIV-1 on these anti-HIV-2-reactive samples differed in their responses. All samples reacted in a licensed anti-HIV-1 Western blot, but there was an atypical band near the p41 position, which could be a clue to the fact that this result was a cross-reaction with anti-HIV-2. A recombinant immunoblot gave an indeterminate result for anti-HIV-1 in all 12 samples. A local immunofluorescence assay for anti-HIV-1 reacted with 92 percent of the samples, but a commercial one detected only 58 percent.  相似文献   
66.
BACKGROUND: A photochemical treatment process has been developed for the inactivation of viruses and bacteria in platelet concentrates. This process is based on the photochemical reaction of a novel psoralen, S- 59, with nucleic acids upon illumination with long-wavelength ultraviolet light (UVA, 320–400 nm). STUDY DESIGN AND METHODS: High levels of pathogens were added to single-donor platelet concentrates containing 3 to 5 × 10(11) platelets in 300 mL of 35-percent autologous plasma and 65-percent platelet additive solution. After treatment with S-59 (150 microM) and UVA (0-3 J/cm2), the infectivity of each pathogen was measured with established biologic assays. In vitro platelet function after photochemical treatment was evaluated during 7 days of storage by using a panel of 14 assays. The in vivo recovery and life span of photochemically treated platelets were evaluated after 24 hours of storage in a primate transfusion model. RESULTS: The following levels of pathogen inactivation were achieved:>10(6.7) plaque-forming units (PFU) per mL of cell-free human immunodeficiency virus (HIV),>10(6.6) PFU per mL of cell-associated HIV,>10(6.8) infectious dose (ID50) per mL of duck hepatitis B virus (a model for hepatitis B virus),>10(6.5) PFU per mL of bovine viral diarrhea virus (a model for hepatitis C virus),>10(6.6) colony-forming units of Staphylococcus epidermidis, and>10(5.6) colony-forming units of Klebsiella pneumoniae. Expression of integrated HIV was inhibited by 0.1 microM S- 59 and 1 J per cm2 of UVA. In vitro and in vivo platelet function were adequately maintained after antiviral and antibacterial treatment. CONCLUSION: Photochemical treatment of platelet concentrates offers the potential for reducing transfusion-related viral and bacterial diseases.  相似文献   
67.

Aims

The laparoscopic approach to tumour nephrectomy in children is controversial. We therefore reviewed our institution's cases of tumour nephrectomy (laparoscopic, open, and converted) to better understand which is suitable for this approach, what factors prevent it, and whether one can excise tumours greater than the CCLG recommendation of 300 ml.

Methods

All tumour nephrectomies performed between 2002 and 2016 were identified using our surgical database. Further data were gathered from radiology and pathology databases. Those with nonrenal tumours or having a partial nephrectomy were excluded. Tumour maximum diameters, volumes, and ratios to contralateral kidneys were calculated. A Mann–Whitney U was used to compare the groups.

Results

Forty-three cases were included. Fifteen procedures were completed laparoscopically (35%), and a further 3 converted. The median age at surgery was 2.5 years (range 0–10) in the laparoscopic group and 2 years (range 0–15) in the open group. There was a significant difference (P < 0.05) between the laparoscopic and open groups for: median maximum diameter (10cm vs 12.25cm), median volume (155 ml vs 459 ml), maximum diameter ratio (1.22 vs 1.75), and volume ratio (3.8 vs 11.2).

Conclusion

Tumours in the laparoscopic group were significantly smaller, but it was possible to excise tumours more than 300 ml. Difficulties in excision related to tumour size relative to the abdomen. Therefore, a ratio of tumour to contralateral kidney may be a better guide to safe excision than an overall volume cutoff. From our series, the laparoscopic approach is likely to be achievable if the volume ratio is ≤ 8.1.

Level of evidence

Level 3.  相似文献   
68.
The prognostic significance of c-kit receptor expression on leukemic blast cells was determined in 122 children with acute myeloid leukemia (AML) entered onto Childrens Cancer Group protocol 213. Clinical and laboratory characteristics as well as outcome were analyzed according to the percentage of blast cells expressing c-kit receptors and the relative number of c-kit receptors per cell as determined by indirect immunofluorescence. c-kit receptor expression was strongly associated with the expression of the CD34 antigen. However, contrary to findings in adult patients with AML, c-kit receptor expression by childhood AML blast cells was not predictive of a poor response to therapy.  相似文献   
69.
目的:通过分析黄体生成素(LH)受体基因敲除小鼠子宫生长发育相关基因表达的改变,探讨LH对子宫生长发育的影响。方法:应用基因芯片和RT-PCR方法分析LH受体基因敲除鼠子宫基因表达。结果:155个基因表达改变超过3倍;与生长发育相关的基因中,10个基因表达上调、5个基因表达下调;细胞周期蛋白cyclin D基因上调、cyclin B基因下调,半定量RT-PCR分析证实了细胞周期蛋白基因表达的变化,表明LH受体基因敲除鼠子宫细胞生长发生阻滞,21 d雌二醇和孕酮替代疗法不能够使这些基因表达的改变完全恢复正常。结论:LH除促进卵巢类固醇激素合成调控子宫生长发育外,还对子宫生长发育直接起作用。  相似文献   
70.
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