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91.
From all types of cancer, cervical cancer manages to be in top four most frequent types, with a 6.5% rate of occurrence. The infectious vector that induces the disease, the high-risk Human papillomavirus (HPV), which is a sexually transmitted virus, is capable of transforming the host cell by modulating some of the principal signaling pathways responsible for cell cycle arrest, proliferation, and survival. Fortunately, like other cancer types, cervical cancer can be treated by chirurgical interventions or chemoradiotherapy, but these methods are not exactly the lucky clover of modern medicine because of the adverse effects they have. That is the reason why in the last years the emphasis has been on alternative medicine, more specifically on phytochemicals, as a substantial number of studies showed that diet contributes to cancer prevention and treatment. All these studies are trying to find new chemopreventive agents with less toxicity but high effectiveness both in vitro and in vivo. The aim of this review is to evaluate the literature in order to underline the advantages and disadvantages of polyphenols, a class of dietary compounds, as chemopreventive and chemotherapeutic agents. This review also aims to present polyphenols from different perspectives, starting with mechanisms of action and ending with their toxicity. The bigger picture illustrates that polyphenols have great potential in cervical cancer prevention, with strong effects on gene modulation.  相似文献   
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93.
A product study is reported on the gas-phase reactions of OH and NO3 radicals and ozone with propyl vinyl ether (PVE). The experiments were performed in a 405 L borosilicate glass chamber in synthetic air at 298 +/- 3 K using long path in situ FTIR spectroscopy for the analysis of the reactants and products. In the presence of NO(x) (NO + NO2) the main products for the OH-radical initiated oxidation of PVE were propylformate and formaldehyde with molar formation yields of 78.6 +/- 8.8% and 75.9 +/- 8.4%, respectively. In the absence of NO(x) propylformate and formaldehyde were formed with molar formation yields of 63.0 +/- 9.0% and 61.3 +/- 6.3%, respectively. In the reaction of NO3 radicals with PVE propylformate 52.7 +/- 5.9% and formaldehyde 55.0 +/- 6.3% were again observed as major products. The ozonolysis of PVE led to the production of propylformate, formaldehyde, hydroxyperoxymethyl formate (HPMF; HC(O)OCH2OOH), and CO with molar formation yields of 89.0 +/- 11.4%, 12.9 +/- 4.0%, 13.0 +/- 3.4%, and 10.9 +/- 2.6%, respectively. The formation yield of OH radicals in the ozonolysis of PVE was estimated to be 17 +/- 9%. Simple atmospheric degradation mechanisms are postulated to explain the formation of the observed products.  相似文献   
94.
This paper proposes a new morphology-based approach for the interslice interpolation of current transformer (CT) and MRI datasets composed of parallel slices. Our approach is object based and accepts as input data binary slices belonging to the same anatomical structure. Such slices may contain one or more regions, since topological changes between two adjacent slices may occur. Our approach handles explicitly interslice topology changes by decomposing a many-to-many correspondence into three fundamental cases: one-to-one, one-to-many, and zero-to-one correspondences. The proposed interpolation process is iterative. One iteration of this process computes a transition sequence between a pair of corresponding input slices, and selects the element located at equal distance from the input slices. This algorithmic design yields a gradual, smooth change of shape between the input slices. Therefore, the main contribution of our approach is its ability to interpolate between two anatomic shapes by creating a smooth, gradual change of shape, and without generating over-smoothed interpolated shapes.   相似文献   
95.
The present survey of the publishing habits of women in the Journal of Counseling Psychology found that women published in this journal in higher proportion than would be expected by their membership in Division 17 of the American Psychological Association at the end of the past decade. Women published in the Journal of Counseling Psychology at the end of the 1970s in proportion to the percentage of women who earned counseling psychology PhDs in the mid-1970s. Women published most often with members of the opposite sex, whereas men published with members of the same sex. When men and women published together, first authors were generally men; however, when articles where one man published with one woman were examined, first authorship was shared equally between the sexes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
Evaluated college counseling center usage for 217 women and 593 men who had been encouraged to return to the counseling center for feedback on their freshmen tests. Students who initially approached the counseling center to request feedback on their tests were more likely to obtain counseling for non-test-related problems than were students who never requested their test results, although the mean number of counseling sessions did not differ for the 2 groups. There was a slight tendency for more men than women to request feedback prior to requesting counseling even though there were no sex differences in mean number of sessions. However, a larger proportion of men than women returned for counseling during the same semester in which they received their freshmen test results, and these men, on the average, remained longer in counseling. (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
98.
Chlorogenic acid (5-O-caffeoylquinic acid) is a phenolic compound from the hydroxycinnamic acid family. Epidemiological, biological, and biochemical studies concur to support the beneficial role of chlorogenic acid in human health, along with other dietary phenolic compounds. Thus, chlorogenic acid has been reported to exert inhibitory effects on carcinogenesis in the large intestine, liver, and tongue, and a protective action on oxidative stress in vivo, together with anti-inflammatory, antidiabetic and antihypertensive activities. It is also claimed to have antifungal, antibacterial and antiviral effects with relatively low toxicity and side effects, alongside properties that do not lead to antimicrobial resistance. Due to its importance, numerous methods for determining chlorogenic acid (CGA), as well as for its derivatives from coffee beans and other plants, were elaborated. The most frequently used methods are infrared spectroscopy, high performance liquid chromatography (HPLC), capillary electrophoresis, liquid chromatography-mass spectrometry and chemiluminescence. Although these methods proved to be efficient for quantifying CGA and its derived products, a number of deficiencies were identified: they are time consuming, laborious, and require expensive instruments. Therefore, electrochemical methods have been developed and used in the determination of CGA in different nutraceuticals or food products. The present review aims to present the main progresses and performance characteristics of electrochemical sensors and biosensors used to detect CGA, as it is reported in a high number of relevant scientific papers published mainly in the last decade.  相似文献   
99.
Allogeneic hematopoietic cell transplantation (allo-HCT) has the potential to cure malignant and non-malignant hematological disorders, but because of the serious side effects of this intervention its applications are limited to a restricted number of diseases. Graft-versus-host disease (GvHD) is the most frequent complication and the leading cause of mortality and morbidity following allo-HCT. It results from the attack of the transplanted T cells from the graft against the cells of the recipient. There is no clear treatment for this severe complication. Due to their immunomodulatory properties, mesenchymal stromal cells (MSC) have been proposed to treat GvHD, but the results did not meet expectations. We have previously showed that the immunomodulatory effect of the MSC was significantly enhanced through adenoviral-mediated overexpression of FasL. In this study, we have tested the properties of FasL-overexpressing MSC in vivo, in a mouse model for acute GvHD. We found that treatment with FasL-overexpressing MSC delayed the onset of the disease and increased survival of the mice.  相似文献   
100.
Plasma membrane is the initial sensor of different stress conditions and its composition is modified with response to environmental changes. In the present study, we have modified the lipid composition of the membrane by growing Saccharomyces cerevisiae in the presence of different fatty acids and ergosterol. All supplemented fatty acids were incorporated into the cell and this incorporation produced significant changes in the lipid composition. The incubation with ergosterol also modified the lipid composition of the cells; however, these cells presented a strong reduction in the content of this sterol. The different cellular lipid composition has been related to viability and fermentation performance at low temperature (13 °C). The cells incubated with palmitoleic acid (C16:1) showed higher viability and significant reduction in the fermentation length. These cells presented higher C16:1 and ergosterol content, shorter chain length of the fatty acids and higher ratio of sterols/phospholipids. Therefore redesigning the composition of cellular membranes during industrial yeast propagation seems to be a promising strategy for improving fermentation performance in the winery.  相似文献   
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