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排序方式: 共有313条查询结果,搜索用时 31 毫秒
21.
Sympathetic activation in dogs with congestive heart failure caused by chronic mitral valve disease and dilated cardiomyopathy 总被引:1,自引:0,他引:1
W A Ware D D Lund A R Subieta P G Schmid 《Journal of the American Veterinary Medical Association》1990,197(11):1475-1481
Baseline plasma norepinephrine (NE) and epinephrine (EPI) concentrations were measured in dogs with naturally acquired heart failure (HF) caused by either degenerative mitral valve disease and mitral regurgitation (MR) or idiopathic dilated cardiomyopathy (DCM). Compared with controls (clinically normal), dogs with HF had increased plasma NE concentration, which was correlated positively with clinical severity of HF. Dogs with the most severe degree of HF (New York Heart Association functional class IV) had mean NE concentration significantly (P less than 0.05) greater than that of dogs with all other functional classes of HF. Overall, mean NE concentration in dogs with DCM was greater than that in dogs with MR. Plasma EPI concentration was not different between control dogs and dogs with HF or between dogs with DCM or MR. Correlations were not found between the echocardiographically derived end systolic volume index (used as an estimate of myocardial function) and plasma NE and EPI concentrations or serum sodium or potassium concentration. Dogs with DCM, as a group, had a small but significant (P less than 0.05) decrease in serum sodium concentration, compared with dogs with MR. This difference was maintained only for class-IV HF when dogs were separated according to functional HF class. In dogs with DCM, significant inverse correlation was found between plasma NE and serum sodium concentrations. When grouped together, all dogs with HF maintained this relationship; however, dogs with MR did not have correlation between plasma NE and serum sodium concentrations. Plasma EPI and serum sodium concentrations were not correlated for any group. It was concluded that in dogs, plasma NE, but not EPI, concentration is high in relation to the clinical severity of naturally acquired HF.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
22.
Rodomiro Ortiz Birgitte Lund Sven-Bode Andersen 《Genetic Resources and Crop Evolution》2003,50(5):455-459
Phenotypic diversity among 75 Nordic spring wheat cultivars was assessed in a glasshouse experiment, in which plots had no fertilizer or received 14-3-23 NPK plus Mg. On average, the fertilizer application delayed flowering by one day, shortened plant height (PH), as well as enhanced the number of fertile tillers (NFT), fresh and dry straw weight (FSW and DSW, respectively), but influenced negatively the dry matter content in the straw (DMCS) and the number of kernels per spike (K/S). The cultivar-by-fertilizer interaction did not affect significantly days to flowering (DF), PH, FSW, DSW, DMCS, thousand kernel weight, and K/S. Only NFT was significantly affected by this interaction. There were significant differences among cultivars for all characteristics, and the breeding gains were significant for improving earliness (as determined by DF), shortening PH, as well as for reducing DSW and DMCS irrespective of the environment. On average, FSW was low in newer cultivars grown in high inputs, while NFT was low in newer cultivars when grown in low inputs. The country of origin affected significantly DF, PH, DMCS, K/S, and 1000-kernel weight. On average, cultivars developed for Finland and Norway were significantly taller, and had higher DMCS. Finnish cultivars also flowered 1 or 2 days earlier and showed higher K/S than cultivars adopted in southern Scandinavia or Norway. 相似文献
23.
During normal mouse development the relative amounts of two types of U1 small nuclear RNA's (U1 RNA) change significantly. Fetal tissues have comparable levels of the two major types of mouse U1 RNA's, mU1a and mU1b, whereas most differentiated adult tissues contain only mU1a RNA's. Those adult tissues that also accumulate detectable amounts of embryonic (mU1b) RNA's (for example, testis, spleen, and thymus) contain a significant proportion of stem cells capable of further differentiation. Several strains of mice express minor sequence variants of U1 RNA's that are subject to the same developmental controls as the major types of adult and embryonic U1 RNA. The differential accumulation of embryonic U1 RNA's may influence the pattern of gene expression during early development and differentiation. 相似文献
24.
How does III x II make U6? 总被引:4,自引:0,他引:4
25.
Lund E Engeset D Alsaker E Skeie G Hjårtaker A Lundebye AK Niebor E 《Science (New York, N.Y.)》2004,305(5683):477-8; author reply 477-8
26.
Determination and depletion of residues of carbadox, tylosin, and virginiamycin in kidney, liver, and muscle of pigs in feeding experiments 总被引:1,自引:0,他引:1
M G Lauridsen C Lund M Jacobsen 《Journal of the Association of Official Analytical Chemists》1988,71(5):921-925
The results of residue determinations of the growth promotors carbadox, tylosin, and virginiamycin in kidney, liver, and muscle from pigs in feeding experiments are described as well as the analytical methods used. Residues of the carbadox metabolite quinoxaline-2-carboxylic acid were found in liver from pigs fed 20 mg/kg in the diet with a withdrawal time of 30 days. No residues were detected in muscle with zero withdrawal time. The limit of determination was 0.01 mg/kg for both tissues. No residues of virginiamycin and tylosin were found in pigs fed 50 and 40 mg/kg, respectively, in the diet, even with zero withdrawal time. Residues of tylosin of 0.06 mg/kg and below were detected in liver and kidney from pigs fed 200 or 400 mg/kg and slaughtered within 3 h after the last feeding. 相似文献
27.
Effects of Brussels sprout juice on the cell cycle and adhesion of human colorectal carcinoma cells (HT29) in vitro 总被引:2,自引:0,他引:2
Smith TK Lund EK Clarke RG Bennett RN Johnson IT 《Journal of agricultural and food chemistry》2005,53(10):3895-3901
Consumption of Brassica vegetables is associated with a reduced risk of cancer of the alimentary tract in animal models and human populations. We used raw juice extracted from Brussels sprouts rich in the glucosinolate sinigrin to explore the effect of naturally occurring glucosinolate breakdown products on cell cycle progression and apoptosis in human colorectal carcinoma cells (HT29). Juice was prepared from sprout tissue immediately before use, and the glucosinolate breakdown products were determined by gas chromatography mass spectrometry and liquid chromatography mass spectrometry. The cell cycle was analyzed by flow cytometry on detached and adherent cells, and apoptosis was measured in the detached population by annexin V staining. Twenty-four hours after challenge with juice (10 microL/mL), 7-13% of adherent cells had detached from the substratum but the majority (82%) of these cells had not entered apoptosis, whereas only 33% of detached control cells were not apoptotic (p < 0.05). The main glucosinolate breakdown products were as follows: the sinigrin breakdown product, 1-cyano-2,3-epithiopropane (ca. 38 mM); the gluconapin hydrolysis product, 3-butenyl isothiocyanate (ca. 2.2.mM); the glucobrassicin metabolite, ascorbigen (ca. 8 mM); and low concentrations of other indole glucosinolate-derived hydrolysis products such as neoascorbigen and 3,3'-diindolylmethane. A variety of biologically active glucosinolate breakdown products are released by mechanical disruption of raw Brussels sprout tissue, but contrary to previous assumptions, allyl isothiocyanate is not the main compound responsible for the inhibition of cell proliferation. 相似文献
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Six cases of scrapie were confirmed in two separately maintained flocks of moufflon, in both of which the disease appeared to be endemic. The clinical signs and histopathology were indistinguishable from those observed in scrapie-affected domesticated sheep. The pathology included lesions in the cerebral cortex which, although commonly present in scrapie-affected sheep, have not previously been described in the natural disease. 相似文献