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21.
Challa  A; Rao  DR; Reddy  BS 《Carcinogenesis》1997,18(10):2023-2026
Several epidemiological studies point to a strong correlation between nutrient composition of the diet and cancer of the colon. Phytic acid, present in grains, has been credited with reducing the risk of cancer of the colon. A number of reports are available indicating the benefits of green tea consumption in reducing the risk of stomach, lung and skin cancer, but little data are available on the effect of green tea in reducing the risk of colon cancer. Also, there are no studies on the combined effect of these compounds on colon tumorigenesis. Thus the primary objective of this investigation was to elucidate the combined effects of green tea and phytic acid on colonic preneoplastic lesions and the Phase II enzyme glutathione S-transferase. Fisher 344 male weanling rats were divided into nine groups of 15 rats each and fed the experimental diet for 13 weeks. Rats received two s.c. injections of azoxymethane in saline at 16 mg/kg body wt at 7 and 8 weeks of age. Rats received three levels (0, 1 and 2%) of phytic acid with three levels (0, 1 and 2%) of green tea within each phytic acid level in a 3 x 3 factorial experiment. Results indicate that while green tea had a marginal effect (P < 0.14), phytic acid significantly reduced the incidence of aberrant crypt foci (P < 0.008). The interaction between green tea and phytic acid was significant (P < 0.029 for distal and < 0.0168 for entire colon) and positive, pointing to a synergistic effect of green tea and phytic acid.   相似文献   
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Abnormal expression of hepatoma specific gamma-glutamyl transferase and alteration of gamma-glutamyl transferase gene methylation status in patients with hepatocellular carcinoma@Jiang DR @Huang ZW @Lu JX @Tao QY @Yu JZ @Meng XY  相似文献   
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Biopsy specimens of clinically normal skin of 9 consecutive patients with SLE were examined ultrastructurally to determine the presence and frequency of microtubular inclusions. Ten blood vessels were examined in each specimen; every specimen contained at least two positive blood vessels, and some contained 80 to 100% positive vessels. No correlation was found between the frequency of the inclusions and either the disease duration or antinuclear factor titer. The inclusions tended to be more frequent in patients with more acute disease. The absence of inclusions in normal skin may mitigate a diagnosis of SLE.  相似文献   
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BACKGROUND & AIMS: Shwachman syndrome is an inherited condition with multisystemic abnormalities, including exocrine pancreatic dysfunction. The aim of this study was to evaluate the occurrence and progression of features in a large cohort of patients. METHODS: Clinical records of 25 patients with Shwachman syndrome were reviewed. RESULTS: Mean birth weight (2.92 +/- 0.51 kg) was at the 25th percentile. However, by 6 months of age, mean heights and weights were less than the 5th percentile. After 6 months of age, growth velocity was normal. Severe fat maldigestion due to pancreatic insufficiency was present in early life (fecal fat, 26% +/- 17% of fat intake; age, < 2 years). Serial assessment of exocrine pancreatic function showed persistent deficits of enzyme secretion, but 45% of patients showed moderate age-related improvements leading to pancreatic sufficiency. Neutropenia was the most common hematologic abnormality (88%), but leukopenia, thrombocytopenia, and anemia were also frequently encountered. Patients with hypoplasia of all three bone marrow cellular lines (n = 11) had the worst prognosis; 5 patients died, 2 of sepsis and 3 of acute myelogenous leukemia. Other findings included hepatomegaly and/or abnormal liver function test results and skeletal abnormalities. CONCLUSIONS: A wide and varied spectrum of phenotypic abnormalities among patients with Shwachman syndrome is described. Pancreatic acinar dysfunction is an invariable abnormality. Patients with severe bone marrow involvement may have a guarded prognosis. (Gastroenterology 1996 Dec;111(6):1593-602)  相似文献   
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The proteins encoded by the rat and porcine luteinizing hormone (LH)lchorionic gonadotropin (CG) receptor cDNAs appear to be unique members of the G -protein-coupled receptor family. Although they have the characteristic seven transmembrane domains, the LH/CG receptors have relatively low homology to other members o f this family, do not have a G-protein-coupling domain corresponding to that of the a-adrenergic receptor, and contain an unusual long extracellular domain. Experience in the molecular dissection of this receptor family will help guide investigation of the LHICG receptor's functional domains. Further studies are needed to clarify the origin and significance of the various mRNA species hybridizing on Northern blot analyses. Finally, the rat and porcine receptor cDNAs should permit cloning of the human LH/CG receptor, as well as cloning of the thyroid-stimulating hormone and follicle-stimulating hormone receptors.  相似文献   
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