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61.
OBJECTIVES: To compare the histological effects of diode and Neodymium-Yttrium Aluminium Garnet (Nd:YAG) laser coagulation of chorionic plate vessels. METHODS: In selected chorionic plate vessels in an ex vivo term placenta perfused with warm saline solution, diode (wavelength 940 nm) and Nd:YAG (wave length 1,064 nm) laser were used with an output of 30, 40, and 50 W, and 55 and 70 W respectively using preset energy and duration of impact. All vessels were examined histologically blindly to the procedures' characteristics. RESULTS: A total of 23 vessels were coagulated. Similar histological lesions were observed using diode and Nd:YAG lasers. The lesions were compatible with an acceptable clinical effect at all power outputs tested. The results were not related to the diameter or type of vessels. Lesions of the endothelium and reduction of the vessel lumen were best achieved with a diode laser at 40 W. CONCLUSION: Nd:YAG and Diode laser induce significant and comparable changes in chorionic plate vessels compatible with an efficient coagulation process under the experimental condition used.  相似文献   
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Increased postmenopausal bone turnover leads to bone loss and fragility fracture risk. In the absence of osteoporosis, risk preventive measures, particularly those modifying nutritional lifestyle, are appropriate. We tested the hypothesis that milk supplementation affects bone turnover related to biochemical markers in a direction that, in the long term, may be expected to reduce postmenopausal bone loss. Thirty healthy postmenopausal women aged 59.3 (SD 3.3) years were enrolled in a prospective crossover trial of 16 weeks. After a 4-week period of adaptation with diet providing 600 mg calcium plus 300 mg ingested as 250 ml semi-skimmed milk, participants were maintained during 6 weeks under the same 600 mg calcium diet and randomized to receive either 500 ml semi-skimmed milk, thus providing a total of 1200 mg calcium, or no milk supplement. In the next 6 weeks they were switched to the alternative regimen. At the end of the each period, i.e. after 4, 10 and 16 weeks, blood and urinary samples were collected. The changes in blood variables between the periods of 6 weeks without and with milk supplementation were: for parathyroid hormone, -3.2 pg/ml (P=0.0054); for crosslinked telopeptide of type I collagen, -624 pg/ml (P<0.0001); for propeptide of type I procollagen, -5.5 ng/ml (P=0.0092); for osteocalcin, -2.8 ng/ml (P=0.0014). In conclusion, a 6-week period of milk supplementation induced a decrease in several biochemical variables compatible with diminished bone turnover mediated by reduction in parathyroid hormone secretion. This nutritional approach to postmenopausal alteration in bone metabolism may be a valuable measure in the primary prevention of osteoporosis.  相似文献   
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Objective: To evaluate antioxidant, cytotoxic, and anti-venom capacity of crude bark extracts of Alstonia parvifolia Merr. Methods: Gas chromatography-mass spec...  相似文献   
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Hepatitis C is a major global health burden with an estimated 160 million infected individuals worldwide. This long-term disease evolves slowly, often leading to chronicity and potentially to liver failure. There is no anti-HCV vaccine, and, until recently, the only treatment available, based on pegylated interferon and ribavirin, was partially effective, and had considerable side effects. With recent advances in the understanding of the HCV life cycle, the development of promising direct acting antivirals (DAAs) has been achieved. Their use in combination with the current treatment has led to encouraging results for HCV genotype 1 patients. However, this therapy is quite expensive and will probably not be accessible for all patients worldwide. For this reason, constant efforts are being made to identify new antiviral molecules. Recent reports about natural compounds highlight their antiviral activity against HCV. Here, we aim to review the natural molecules that interfere with the HCV life cycle and discuss their potential use in HCV therapy.  相似文献   
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Epidemiological studies report that exposure to pesticides like chlordecone and lindane increases risk of cancer. They may act as endocrine disruptors via the activation of estrogen receptor α (ERα). Carcinogenesis involved angiogenesis and no available data regarding these organochlorines have been reported. The present study aimed at investigating the effects of lindane and chlordecone on cellular processes leading to angiogenesis through an involvement of ERα. Angiogenesis has been analyzed both in vitro, on human endothelial cells, and in vivo by quantifying neovascularization with the use of ECMgel? plug in mice. Both pesticides increased endothelial cell proliferation, migration and MMP2 activity. These toxics potentiated cell adhesion by enhancing FAK phosphorylation and stress fibers. The two organochlorines increased nitric oxide production via an enhancement of eNOS activity without modification of oxidative stress. Evidence has been provided that the two toxins increased in vivo neovascularization. Most interestingly, all the above processes were either partially or completely prevented after silencing of ERα. Altogether, these data highlight that organochlorines modulate cellular angiogenic processes through activation of ERα. This study further reinforces the harmful effects of these pesticides in carcinogenesis, particularly in the modulation of angiogenesis, a critical step in tumor promotion, through ERα.  相似文献   
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Erythropoietin (EPO) is the main regulator of red blood cell production but there exists also a variety of nonhematopoietic properties. More recent data show that EPO is also associated with the protection of tissues suffering from ischemia and reperfusion injury as well as with improved regeneration in various organ systems, in particular the skin. This review highlights the mechanisms of EPO in the different stages of wound healing and the reparative processes in the skin emphasizing pathophysiological mechanisms and potential clinical applications. There is clear evidence that EPO effectively influences all wound‐healing phases in a dose‐dependent manner. This includes inflammation, tissue, and blood vessel formation as well as the remodeling of the wound. The molecular mechanism is predominantly based on an increased expression of the endothelial and inducible nitric oxide (NO) synthase with a consecutive rapid supply of NO as well as an increased content of vascular endothelial growth factor (VEGF) in the wound. The improved understanding of the functions and regulatory mechanisms of EPO in the context of wound‐healing problems and ischemia/reperfusion injury, especially during flap surgery, may lead to new considerations of this growth hormone for its regular clinical application in patients.  相似文献   
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