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51.
Although insects lack the adaptive immune response of the mammalians, they manifest effective innate immune responses, which include both cellular and humoral components. Cellular responses are mediated by hemocytes, and humoral responses include the activation of proteolytic cascades that initiate many events, including NO production. In mammals, nitric oxide synthases (NOSs) are also present in the endothelium, the brain, the adrenal glands, and the platelets. Studies on the distribution of NO-producing systems in invertebrates have revealed functional similarities between NOS in this group and vertebrates. We attempted to localize NOS activity in tissues of na?ve (UIL), yeast-injected (YIL), and saline-injected (SIL) larvae of the blowfly Chrysomya megacephala, using the NADPH diaphorase technique. Our findings revealed similar levels of NOS activity in muscle, fat body, Malpighian tubule, gut, and brain, suggesting that NO synthesis may not be involved in the immune response of these larval systems. These results were compared to many studies that recorded the involvement of NO in various physiological functions of insects. 相似文献
52.
Iñigo Arozarena Belén Ayestarán María Cantalejo Montserrat Navarro Marta Vera Irene Abril Ana Casp 《European Food Research and Technology》2002,214(4):303-309
The anthocyanin composition of Tempranillo, Garnacha and Cabernet Sauvignon grapes over two vintages was studied. Samples were obtained during berry ripening from two vineyards that differed by producing fruit of high and low quality. The proportions of the individual compounds remained practically constant within a single vineyard along the sampling period, the changes in the anthocyanin composition being principally quantitative. Different multivariate statistical methods showed that the anthocyanin profile was primarily determined by variety. This genetic dependence was particularly verified when the sums of the non-acylated glucosides, the acetates and the p-coumaryl derivatives, were analysed. The mean relative content corresponding to these three anthocyanin fractions was always the same within each variety, independently either of the vineyard or the vintage year considered. Relating to the individual compounds, several permanent qualitative differences between vineyards in each variety were also found, although the difference in the total anthocyanin concentration was always much higher. 相似文献
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D Krajícková JH Peregrin J Stríbrná A Belán S Vítko 《Canadian Metallurgical Quarterly》1997,43(12):775-780
The objective of the work was to evaluate the contribution of percutaneous transluminal angioplasty (PTA) to treatment of hypertension and the graft function of a transplanted kidney. Angioplasty of the graft artery was performed in 39 patients. Technical success rate: 85%. Complications: 13%--in particular during the first years after introduction of the method. Twenty seven patients were followed up on a long-term basis. Changes of the median arterial pressure (MAP) were evaluated as well as glomerular filtration (GF) assessed by creatinine clearance. Mean values: [table: see text] A statistically significant (p < 0.01) reduction of the median arterial pressure (drop by > 10 mm Hg) along with reduction of the number of antihypertensive drugs was recorded in 70% of the patients during the first year and in 80% kidney recipients in investigations extending beyond one year. A significant increase of glomerular filtration (by > 20%) was found in 40% of the patients, on average the rise was insignificant. During the follow up period 13 kidney recipients were transferred to a dialyzation programme due to failure of the grafts as a result of rejection. CONCLUSION: Percutaneous transluminal angioplasty of a stenosis of the graft artery is the method of first choice in the treatment of hypertension. It is of fundamental importance also in rare cases in order to preserve or improve graft function and thus delay dialyzation treatment. 相似文献
56.
The purpose of this study was to determine long-term role of nitric oxide in modulating the chronic renal and arterial pressure responses to angiotensin II (AII). In normal dogs, intrarenal AII infusion (1.0 ng/KG/min) decreased renal plasma flow (RPF) by 31% and glomerular filtration rate (GFR) by 17% and increased mean arterial pressure (MAP) by 22%. In dogs with chronic intrarenal NO synthesis blockade with N(omega)-nitro-L-arginine methyl ester (3 micrograms/kg/min), AII decreased RPF by 25% and GFR by 19%, and increased MAP by 7%. These data indicate that chronic inhibition of NO synthesis within the kidney attenuated the long-term renal and arterial pressure responses by AII in dogs. 相似文献
57.
I Van de Vondel L Coppens D Verellen A Bel N Linthout M De Beukeleer D Van den Berge G Storme 《Canadian Metallurgical Quarterly》1998,25(6):897-899
Because of the capability of free movement in the treatment room, we recently introduced a Hercules treatment couch on one of our linear accelerators. One of the advantages of this couch is that it allows for a more flexible way of patient setup and that it can be moved entirely out of the way to enable treatment with a hospital bed. A disadvantage, however, is that the couch can hit a wall or a cover of the accelerator accidentally. A limitation system has been developed to protect both the table and the accelerator against such collisions. 相似文献
58.
CA Dorrepaal MJ Benders P Steendijk M van de Bor F van Bel 《Canadian Metallurgical Quarterly》1993,64(4):193-200
In thirteen preterm infants receiving surfactant (Curosurf) replacement therapy, changes in cerebral hemodynamics and oxygenation were investigated by near infrared spectroscopy. Surfactant instillation led to an instantaneous increase in cerebral blood volume (CBV) in all infants, which was primarily due to an increase in deoxygenated hemoglobin. Five infants received a low dose (100 mg/kg = 1.25 ml/kg) of surfactant and 8 a high dose (200 mg/kg = 2.50 ml/kg). A significantly larger increase in CBV was observed in the infants receiving a high dose compared to those receiving a low dose of surfactant. We conclude that cerebral perfusion is affected more after the instillation of a high dose compared to a low dose of surfactant. 相似文献
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Madrera Roberto Rodríguez Valles Belén Suárez García Yolanda Diñeiro del Valle Argüelles Paula Lobo Anna Picinelli 《Food science and biotechnology》2010,19(4):1129-1134
Work has commenced on the study and characterization of wood native species (oak, chestnut, cherry, alder, ash, and beech),
employed to a minor extent in enology, for their application in the elaboration of distillates. To this end, furanic and low
molecular weight phenol compounds, total phenolic content, and antioxidant activity in alcoholic extracts by maceration of
wood chips at 2 toasting levels were studied. Significant differences between samples, technologically relevant, were due
both to species and toasting time. Furthermore, extracts showed interesting antioxidant activities equivalent in some cases
to than those reported for alcoholic beverages aged in wood. 相似文献