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251.
Diet has an important role in the prevention and treatment of hypertension. In early epidemiological studies, conducted mainly in the USA, monounsaturated fatty acids showed a deleterious association with blood pressure or no relationship at all. However, more recent studies, conducted in Mediterranean countries, have shed new light on this issue. In the present review we summarise the main results of epidemiological studies and feeding trials, and explain the possible mechanisms through which monounsaturated fatty acids, and specifically olive oil as the major dietary source of this type of fat in Mediterranean countries, could exert a favourable effect on blood pressure.  相似文献   
252.
This report describes an uncommon clinical case of cystic parathyroid adenocarcinoma. A 17-year-old male Persian cat was presented for evaluation of a ventral cervical mass. The cat was inappetent and showed weight loss, polydipsia and vomiting. Serum biochemistry and urinalysis revealed moderate hypercalcaemia, a mild increase of creatinine, isosthenuria and proteinuria. Sodium dodecyl sulphate-agarose gel electrophoresis showed a mixed tubular proteinuric pattern, in accordance with histological examination that revealed interstitial nephritis and glomerulonephritis. Diagnosis of parathyroid carcinoma was based on histopathological findings.  相似文献   
253.
Controlled reproduction is a requirement for developing effective mollusc cultivation for commercial or restoration purposes. In this study, a protocol for spawning induction using noninvasive methods in limpets was developed, using the common Mediterranean species, Patella caerulea Linnaeus, 1758. Six nonlethal spawning induction treatments were tested: three chemical (two concentrations of H2O2 and KCl) and three physical (bubbling, warm and cold thermal shock). All treatments, except thermal shocks, induced the spawning of fertile gametes. Bubbling resulted the best treatment in providing spawning response, being the easiest and least invasive method tested. After eggs fertilization, larval development was followed until metamorphosis, testing fed and unfed conditions. Settlement took place after 7 days. The developed protocol represents a benchmark for further application to other limpets, for aquaculture or repopulation.  相似文献   
254.
Citrus germplasm is conserved in genebanks at sites around the world to provide genetic resources for breeding and research programs. The value of genebank collections is particularly evident as diseases and climate change threaten citrus production areas. We provide historical, inventory, and maintenance information about national citrus collections in Russia and in the United States. The Russian Research Institute of Floriculture and Subtropical Crops (RRIFSC) in Sochi, Russia maintains a collection of 132 citrus accessions representing 50 taxa. Southern Russia is one of the most northerly citrus growing areas in the world and many accessions in the RRIFSC collection were specifically selected for cold tolerance to facilitate citrus production in this region. Tree response data taken during the frequent severe winters in Sochi has provided an understanding of the relative cold tolerance of many RRIFSC accessions. Particularly noteworthy is the array of cold-tolerant lemon accessions maintained at the RRIFSC. The Aurantioideae collections at the United States Department of Agriculture (USDA), Agricultural Research Service (ARS) National Clonal Germplasm Repository for Citrus and Dates (NCGRCD) and at the University of California Citrus Variety Collection in Riverside, California, maintain 1328 accessions of citrus cultivars and wild relatives. Because of federal and state quarantine regulations, accessions at this facility are tested for graft-transmissible pathogens and undergo therapy to eliminate known pathogens. In contrast to Sochi, desert-adapted lemon and grapefruit varieties are a major interest of the California-based collection. The collection of citrus and citrus relatives is being screened for resistance and/or tolerance genes to diseases such as huanglongbing which is currently threatening the US citrus industry. Through collaborative exchange efforts, the diversity in the two genebanks could be expanded to increase availability of desirable genetic resources to breeding and research communities throughout the world.  相似文献   
255.
The kinetics of inhibition of human and horse sera butyryl cholinesterases by solanaceous glycoalkaloids α-solanine, α-chaconine and tomatine has been studied by means of a potentiometric biosensor based on pH-sensitive field effect transistors (pH-FETs). Using acetyl- and butyryl choline as substrates, the optimal pH and the apparent kinetic parameters (Kmapp, Vmaxapp) of immobilized cholinesterases have been calculated in the absence of inhibitors. All studied glycoalkaloids were reversible inhibitors of both butyryl cholinesterases, and inhibited the horse and human immobilized enzymes in competitive and mixed modes, respectively. The affinity of each enzyme towards α-solanine, α-chaconine and tomatine has been estimated through calculation of apparent inhibition constants Kiapp and inhibition coefficients I50. An application of the butyryl cholinesterases studied in the biosensors for glycoalkaloids determination in the concentration range of 10−7 to 10−4 M has been discussed.  相似文献   
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