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61.
Humans may be exposed to pesticides such as fungicides, herbicides, and insecticides, during occupational and non‐occupational activities. Pesticides could be related to cancer development mainly because of their effects on the endocrine and immune systems and their cumulative effect. The present review evaluated in current literature evidence of an association between exposure to pesticides and the occurrence of head and neck cancer (HNC). A literature search for cohort studies was conducted in the PubMed, Web of science, and Cochrane databases. Methodological quality of each study was rated with the Scottish Intercollegiate Guidelines Network (SIGN) checklist. One thousand one hundred and thirty‐two studies were identified. Thirty‐two were included. Most of the studies found addressed occupational exposure to pesticides and were conducted in Europe and North America. Eleven high‐quality studies were found. Most of them found no association between exposure to pesticides and increased risk of HNC. Two studies found some evidence of a positive association between pesticide (malathion and atrazine) exposure and thyroid cancer. The literature review does not support a clear evidence for association between pesticides exposure and HNC. Only limited evidence points to a positive association between exposure to some pesticides and thyroid cancer. Further standardized studies based on appropriate designs are required to clarify the effect of pesticides on the genesis of HNC, considering dose, length of exposure, and type of pesticide.  相似文献   
62.
A 49-year-old woman was hospitalized for acute left foot arterial ischemia. Arterial Doppler revealed occlusion of the dorsalis pedis and posterior tibial arteries. A computed tomography angiography performed to assess abdominal pain showed hepatic, splenic, renal and pancreatic infarctions. A splenic artery embolism and a small aortic wall thrombus at the celiac trunk were identified. No radiological signs of aortic atherosclerosis were found. No predisposing conditions for secondary aortic thrombosis or intracardiac embolic sources were detected. It was determined that primary aortic thrombosis, a rare though potentially serious condition, was to blame. Isolated aortic mural thrombosis therapy is not well established, although systemic anticoagulation, thrombolysis, thromboaspiration, endovascular stent grafting and surgical thrombectomy have been attempted with varying success. In our patient, systemic anticoagulation therapy was initiated and resulted in aortic thrombus resolution. Close clinical follow-up is crucial, as the aortic thrombus can recur despite anticoagulation and aggressive control of the atherosclerotic risk factors.  相似文献   
63.
The understanding of the association between salt intake and precancerous lesions may contribute to clarify the causal relation with gastric cancer. We systematically reviewed 17 articles addressing the association between dietary salt exposure and gastric intestinal metaplasia and conducted meta-analyses for quantitative synthesis (random effects model). Salt exposure was estimated assessing salted/salty food consumption, preference for salted/salty foods, use of table salt, or sodium urinary excretion. Heterogeneity was also large regarding food items evaluated, consumption categories, and data analysis. The combined odds ratio (OR) was 1.68 (95% confidence interval (CI) = 0.98–2.90; I2 = 55.4%) for the association between salted/salty meat and intestinal metaplasia (4 studies) and the OR was 1.53 (95% CI = 0.72–3.24; I2 = 76.8%) for salt preference. There was a positive, nonstatistically significant association between intestinal metaplasia and urinary sodium excretion. The heterogeneity of methodological options and results preclude quantitative synthesis or its proper interpretation, even if the available evidence may suggest a positive association between salt and intestinal metaplasia.  相似文献   
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Triple negative breast cancer has an extremely poor prognosis when chemotherapy is no longer effective. To overcome drug resistance, novel drug delivery systems based on nanoparticles have had remarkable success. We produced a novel nanoparticle component ‘MDC’ from milk-derived colloid. In order to evaluate the anti-cancer effect of MDC, we conducted in vitro and in vivo experiments on cancer cell lines and a primary tumor derived breast xenograft. Doxorubicin (Dox) conjugated to MDC (MDC-Dox) showed higher cancer cell growth inhibition than MDC alone especially in cell lines with high EGFR expression. In a mouse melanoma model, MDC-Dox significantly suppressed tumor growth when compared with free Dox. Moreover, in a primary tumor derived breast xenograft, one of the mice treated with MDC-Dox showed partial regression, while mice treated with free Dox failed to show any suppression of tumor growth. We have shown that a novel nanoparticle compound made of simple milk-derived colloid has the capability for drug conjugation, and serves as a tumor-specific carrier of anti-cancer drugs. Further research on its safety and ability to carry various anti-cancer drugs into multiple drug-resistant primary breast models is warranted.  相似文献   
66.
Working memory abilities significantly decrease with advancing age; hence, the search for factors that may increase or mitigate this decline is critical. Several factors have been identified that influence working memory; however, their effects have been mainly assessed separately and rarely together with other factors in the same sample. We examined 120 variables to search for factors that jointly act as mediators of working memory decay across the adult life span. A sample of 1652 healthy adults was assessed in spatial and verbal working memory domains. Structural equation modeling analyses were conducted to search for potential mediators that intervened between age and working memory. Only 14 and 10 variables reliably mediated spatial and verbal working memory, respectively. Factors from several domains remained in the models, such as individual characteristics, physiological traits, consumption habits, and regular activities. These factors are sufficiently powerful to influence working memory decline when they jointly interact, as in everyday living.  相似文献   
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This observational study aimed to establishing a relationship between lipid peroxidation and endometriosis in women undergoing controlled ovarian hyperstimulation. A total of 79 women were divided into two groups: (i) controls (tubal or male factor); and (ii) endometriosis (stages III/IV). The endometriosis diagnosis was confirmed by videolaparoscopy and the controlled ovarian stimulation protocol was similar to all patients. Follicular fluid (FF) lipid peroxidation levels were determined through the quantification of malondialdehyde. Statistical analysis was performed using parametric and non-parametric tests, logistic regression was performed to estimate the chance of achieving a pregnancy in each group and a moving average was calculated for the endometriosis group. Peroxidation levels in the endometriosis group were significantly higher when compared to controls. The moving average showed a decrease of MDA levels in the endometriosis group with increasing female age. Moreover, women with endometriosis who were under 33 years of age were 4.3 times more likely to achieve a pregnancy than women above that age. In conclusion, endometriosis is associated with increased FF oxidative stress (OS) in patients undergoing in vitro fertilization (IVF). Also, increasing age is associated with a decrease in severity of the oxidative status, but a decreased chance of pregnancy.  相似文献   
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Quantitative data on branching patterns of the human cerebral arterial tree are lacking in the 1.0–0.1 mm radius range. We aimed to collect quantitative data in this range, and to study if the cerebral artery tree complies with the principle of minimal work (Law of Murray). To enable easy quantification of branching patterns a semi-automatic method was employed to measure 1,294 bifurcations and 2,031 segments on 7 T-MRI scans of two corrosion casts embedded in a gel. Additionally, to measure segments with a radius smaller than 0.1 mm, 9.4 T-MRI was used on a small cast section to characterize 1,147 bifurcations and 1,150 segments. Besides MRI, traditional methods were employed. Seven hundred thirty-three bifurcations were manually measured on a corrosion cast and 1,808 bifurcations and 1,799 segment lengths were manually measured on a fresh dissected cerebral arterial tree. Data showed a large variation in branching pattern parameters (asymmetry-ratio, area-ratio, length-radius-ratio, tapering). Part of the variation may be explained by the variation in measurement techniques, number of measurements and location of measurement in the vascular tree. This study confirms that the cerebral arterial tree complies with the principle of minimum work. These data are essential in the future development of more accurate mathematical blood flow models. Anat Rec, 302:1434–1446, 2019. © 2018 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.  相似文献   
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