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BackgroundSeveral prior studies have found an association between statin use and reduced risk of colorectal cancer. We hypothesized that these findings may be due to systematic bias and examined the independent association of colorectal cancer risk with statin use, serum cholesterol, and change in cholesterol concentration.ConclusionsAlthough the risk of colorectal cancer was lower in statin users versus nonusers, no difference was observed among those who continued versus discontinued statin therapy, suggesting the potential for indication bias. The association between decreased serum cholesterol and colorectal cancer risk suggests a cholesterol-lowering effect of undiagnosed malignancy. Clinical judgment should be used when considering causes of cholesterol reduction in patients, including those on statin therapy.  相似文献   
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建立一种靶点蛋白质快速定量检测方法。在原有侧向流动免疫层析技术的基础上,通过优化层析材料和纳米微球的均一性、改进检测区的检测方法,经逐点扫描技术,建立标准浓度曲线,以达到对临床靶点蛋白质的定量检测。以乳腺癌组织中的Her2表达为例,通过对已知浓度样品的检测,验证本技术方法的准确度大于96%。另外,以蛋白质免疫印迹作为组织中特定蛋白质检测金标准,分析临床肿瘤组织中Her2蛋白的含量,其准确率也达到95.5%,而免疫组织化学方法检测准确率仅为69.58%。新型免疫层析法检测结果与靶向治疗患者的愈后密切相关(P<0.01)。改进后的新型免疫层析方法能够准确地对临床靶点蛋白质进行定量检测,而且结合侧向流动技术的简单、快速和易用性,这种新型检测方法可以广泛应用于临床组织标本、血液标本和体液标本中靶点蛋白质的临场定量检测,在一定程度上可以替代免疫组化技术。  相似文献   
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1. Insect galls are abnormal plant growths that develop in response to a stimulus provided by a galling insect. The nutrition hypothesis suggests that the concentrations of nutritive compounds in galls are changed to provide optimum nutrition for the larvae and adults of galling insects. 2. To test the nutrition hypothesis, we determined the concentrations of 20 free amino acids in galls and in galled and ungalled twigs of Quercus fabri during the larval and adult stages of Andricus mukaigawae using high-performance liquid chromatography with ultraviolet–visible detection. 3. At the larval stage, the concentrations of 12 out of 20 amino acids in A. mukaigawae galls were significantly higher than those in galled and ungalled twigs. Asparagine and tryptophan were the most abundant nonessential and essential amino acids, respectively, in A. mukaigawae galls. 4. At the adult stage, the concentrations of most amino acids, except proline, were significantly lower in A. mukaigawae galls than in galled and ungalled twigs. The A. mukaigawae adults may not manipulate amino acid levels because the adults do not feed on galls. The decrease of amino acid levels in adult galls may be viewed as a depletion. 5. The composition of free amino acids in A. mukaigawae galls was significantly different from the composition in galled and ungalled twigs in both the larval and adult stages. 6. Our results may support the nutrition hypothesis. We suggest that a high concentration of proline in A. mukaigawae galls may protect larvae and adults from plant defense responses.  相似文献   
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To investigate the possible mechanisms for biological effects of 1,800 MHz mobile radiofrequency radiation (RFR), the radiation-specific absorption rate was applied at 2 and 4 W/kg, and the exposure mode was 5 min on and 10 min off (conversation mode). Exposure time was 24 h short-term exposure. Following exposure, to detect cell DNA damage, cell apoptosis, and reactive oxygen species (ROS) generation, the Comet assay test, flow cytometry, DAPI (4′,6-diamidino-2-phenylindole dihydrochloride) staining, and a fluorescent probe were used, respectively. Our experiments revealed that mobile phone RFR did not cause DNA damage in marginal cells, and the rate of cell apoptosis did not increase (P > 0.05). However, the production of ROS in the 4 W/kg exposure group was greater than that in the control group (P < 0.05). In conclusion, these results suggest that mobile phone energy was insufficient to cause cell DNA damage and cell apoptosis following short-term exposure, but the cumulative effect of mobile phone radiation still requires further confirmation. Activation of the ROS system plays a significant role in the biological effects of RFR. Bioelectromagnetics. © 2020 The Authors. Bioelectromagnetics published by Wiley Periodicals, Inc.  相似文献   
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Streptococcus pyogenes is commonly found on pharynx, mouth and rarely on skin, lower gastrointestinal tract. It is a potential pathogen causing tonsillitis, pneumonia, endocarditis. The present study was undertaken to study the effects of low shear modeled microgravity on growth, morphology, antibiotic resistance, cross-stress resistance to various stresses and alteration in gene expression of S. pyogenes. The growth analysis performed using UV–Visible spectroscopy indicated decrease in growth of S. pyogenes under low shear modeled microgravity. Morphological analysis by Bio-transmission electron microscopy (TEM), Bio-scanning electron microscopy (SEM) did not reveal much difference between normal and low shear modeled microgravity grown S. pyogenes. The sensitivity of S. pyogenes to antibiotics ampicillin, penicillin, streptomycin, kanamycin, hygromycin, rifampicin indicates that the bacterium is resistant to hygromycin. Further S. pyogenes cultured under low shear modeled microgravity was found to be more sensitive to ampicillin and rifampicin as compared with normal gravity grown S. pyogenes. The bacteria were tested for the acid, osmotic, temperature and oxidative cross stress resistances. The gene expression of S. pyogenes under low shear modeled microgravity analyzed by microarray revealed upregulation of 26 genes and down regulation of 22 genes by a fold change of 1.5.  相似文献   
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MLK-3 kinase is a widely expressed serine/ threonine kinase that bears multiple protein interaction domains and regulates signals mediated by the stress-responsive pathway. Thus, MLK-3 signaling affects numerous cellular processes, raising the possibility that MLK-3 might play a role in oncogenesis. In this report, we describe the fine mapping of the MLK-3 gene within the 11q13.1 chromosomal region. By integrating data from somatic cell hybrids and double color fluorescence in situ hybridization on metaphase chromosomes and DNA fibers, MLK-3 has been assigned approximately 1 Mb telomeric of PYGM, close to the D11S546 locus. Since the MEN1 susceptibility locus is also located within the 11q13.1 region, we have carried out Southern and Northern blot analyses, as well as protein truncation assays to establish whether abnormalities in MLK-3 lead to the development of this familial cancer syndrome. Our observations exclude MLK-3 as the MEN1 gene. Received: 25 September 1996 / Revised: 16 December 1996  相似文献   
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