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1.
Polymethylmethacrylate orbital implants with interconnecting channels. A retrospective study following enucleation in dogs and cats 下载免费PDF全文
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Determination of the potassium balances in diary cows and the examination of daily and lactation period-associated variations 下载免费PDF全文
Sattler N Fecteau G Couture Y Tremblay A 《The Canadian veterinary journal. La revue veterinaire canadienne》2001,42(2):107-115
The objectives of this study were to evaluate a method of determining the internal and external potassium balances in dairy cows and to determine daily and lactation period-associated variations of these balances. Ingested potassium, milk potassium concentration (LK) and potassium urinary fractional clearance (FeK) defined the potassium external balance. Serum (SK) and red blood cell (CIEK) potassium concentrations defined the potassium internal balance. Whole blood, urine, and milk were collected at different times of the day from 19 cows, grouped in 5 lactation periods. Significant differences were observed for LK between lactation periods. Significant variations occurred during the day for CIEK, LK, and FeK. Thus, in order to monitor potassium balances during a time period, samples should be collected at the same time each day. This method of determining both potassium balances simultaneously could be useful in the study of the bovine hypokalemia syndrome. 相似文献
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Summary The pressure membrane and pressure plate techniques were used to establish the moisture content-water potential (M-) relationship of red pine (Pinus resinosa Ait.) sapwood in desorption above the fiber saturation point. The moisture content-water potential relationship is required for the development of a model of drying considering the gradient of water potential as the driving force of moisture in wood. This relationship was established at 18, 56 and 85 °C for radial desorption. The results obtained demonstrate that water potential increases with temperature T at a given moisture content M. There is no significant variation of /T with temperature. Also, there is no plateau at intermediate moisture contents as was the case for the M- relationship of aspen sapwood established in a previous work. The effective integral and differential pore size distributions inferred from the M- relationship are also presented. The largest proportion of effective pore openings was found for a radius of 0.2 m. This value can be related to the pit membrane openings of red pine.This research project is currently supported by the Natural Sciences and Engineering Research Council of Canada under grant no. OGP0121954 相似文献
5.
We assessed clonal variation in morphological variables, mineral nutrition, root growth capacity, net photosynthesis, tannin distribution, and cuticle and epicuticular wax features within four families of white spruce (Picea glauca (Moench) Voss). Seeds were collected from four families obtained through controlled crosses among selected genotypes. For each family, plants were produced either from seeds (zygotic) or by somatic embryogenesis (clones). Each family was therefore represented by its zygotic seedlings and three clones. Within a family and under similar growth conditions, several clones differed significantly from the zygotic seedlings in height, root-collar diameter, needle dry mass, branch density, shoot dry mass, root dry mass, and length of needles. Branch density (number of first-order branches per cm height) of zygotic seedlings and clones varied from 0.8 to 1.4 branches cm(-1) and from 0.6 to 1.3 branches cm(-1), respectively. Mean needle length of zygotic seedlings and clones ranged from 11 to 14 mm and from 11 to 17 mm, respectively. For many variables (height, dry mass of new roots, needle dry mass and branch density), differences among clones were significantly greater than differences among zygotic seedlings within a family. Tannins were more abundant in needles of clones than in needles of zygotic seedlings. In some clones, tannins occurred as a ribbon along the central vacuole, whereas in others they appeared as aggregates dispersed in the vacuole. Within a family, N, P and K showed considerable variations in their use efficiency. Interclonal variations were observed in root growth potential and net photosynthesis. Variations in growth and physiology reflect genetically determined differences among clones within a family. 相似文献
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New Forests - Permanent landscape attributes such as topography (elevation [m]) and microtopography (local variation in elevation [cm]) can increase the risk of cold air drainage down-slopes and in... 相似文献
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Romain Gastineau Fran?ois Turcotte Jean-Bernard Pouvreau Michèle Moran?ais Jo?l Fleurence Eko Windarto Fiddy Semba Prasetiya Sulastri Arsad Pascal Jaouen Mathieu Babin Laurence Coiffard Céline Couteau Jean-Fran?ois Bardeau Boris Jacquette Vincent Leignel Yann Hardivillier Isabelle Marcotte Nathalie Bourgougnon Réjean Tremblay Jean-Sébastien Deschênes Hope Badawy Pamela Pasetto Nikolai Davidovich Gert Hansen Jens Dittmer Jean-Luc Mouget 《Marine drugs》2014,12(6):3161-3189
In diatoms, the main photosynthetic pigments are chlorophylls a and c, fucoxanthin, diadinoxanthin and diatoxanthin. The marine pennate diatom Haslea ostrearia has long been known for producing, in addition to these generic pigments, a water-soluble blue pigment, marennine. This pigment, responsible for the greening of oysters in western France, presents different biological activities: allelopathic, antioxidant, antibacterial, antiviral, and growth-inhibiting. A method to extract and purify marennine has been developed, but its chemical structure could hitherto not be resolved. For decades, H. ostrearia was the only organism known to produce marennine, and can be found worldwide. Our knowledge about H. ostrearia-like diatom biodiversity has recently been extended with the discovery of several new species of blue diatoms, the recently described H. karadagensis, H. silbo sp. inedit. and H. provincialis sp. inedit. These blue diatoms produce different marennine-like pigments, which belong to the same chemical family and present similar biological activities. Aside from being a potential source of natural blue pigments, H. ostrearia-like diatoms thus present a commercial potential for aquaculture, cosmetics, food and health industries. 相似文献
9.
Serum osteocalcin or bone Gla-protein, a biochemical marker for bone metabolism in horses: differences in serum levels with age. 总被引:2,自引:1,他引:1 下载免费PDF全文
Levels of alkaline phosphatase and osteocalcin or bone Gla-protein, a new marker of bone metabolism, were analyzed in blood samples of 50 clinically normal female Standardbred horses between four months and twenty years of age. Samples were collected in the morning before exercise. Serum osteocalcin was measured by radioimmunoassay using bovine antibodies. There was a significant inverse correlation between alkaline phosphatase, osteocalcin and the age of the animals up to 48 months. The decrease in osteocalcin levels in serum was very marked during the first 30 months of life. The mean osteocalcin concentration was respectively 47.3, 35.7 and 6.7 ng/mL for animals less than one year, between 1.5 and 2.5 years of age and older than 3.5 years. Alkaline phosphatase serum activity was higher in foals less than one year of age (means = 856 U/L) than in the two older groups (meansII = 339, meansIII = 351 U/L). We believe that osteocalcin is a useful parameter for the evaluation of bone metabolism in growing animals and in adults and is probably more specific than alkaline phosphatase. 相似文献
10.
Increased insulin sensitivity and obesity resistance in mice lacking the protein tyrosine phosphatase-1B gene 总被引:1,自引:0,他引:1
Elchebly M Payette P Michaliszyn E Cromlish W Collins S Loy AL Normandin D Cheng A Himms-Hagen J Chan CC Ramachandran C Gresser MJ Tremblay ML Kennedy BP 《Science (New York, N.Y.)》1999,283(5407):1544-1548
Protein tyrosine phosphatase-1B (PTP-1B) has been implicated in the negative regulation of insulin signaling. Disruption of the mouse homolog of the gene encoding PTP-1B yielded healthy mice that, in the fed state, had blood glucose concentrations that were slightly lower and concentrations of circulating insulin that were one-half those of their PTP-1B+/+ littermates. The enhanced insulin sensitivity of the PTP-1B-/- mice was also evident in glucose and insulin tolerance tests. The PTP-1B-/- mice showed increased phosphorylation of the insulin receptor in liver and muscle tissue after insulin injection in comparison to PTP-1B+/+ mice. On a high-fat diet, the PTP-1B-/- and PTP-1B+/- mice were resistant to weight gain and remained insulin sensitive, whereas the PTP-1B+/+ mice rapidly gained weight and became insulin resistant. These results demonstrate that PTP-1B has a major role in modulating both insulin sensitivity and fuel metabolism, thereby establishing it as a potential therapeutic target in the treatment of type 2 diabetes and obesity. 相似文献