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81.
82.
SuccessionisthedynanucdeveloPInentofecosystemswhichcanbecharactetindbyenergyandndneralcyclings.Eachsuccessionstagehasitscharaceristicsofelementcycling.SomeschOlarshaveStatedbutbrieflawsofnutrienCyclinginsuccessionstagesI"3I.InthespaPer,thenutrientcyclingcharacterishcsofbirchsuccessionseriesinXiaokinganlingwerediscussed.SwrYAasAroarernoDSThestUdyareaislocatedinLiangshniNatUralReservesinthendddieofXiaox-ing'anlilg(l28"53,2o'rE,47olo'5O"N).Theclimat6belongstocontinentalmonsoonclimate,W… 相似文献
83.
INTRODUCTIONThcstcmfonl1ofnaturalKorcanpincforcst.ot\ingtothcsupprcsscdandshadcd,isvcry'difTcrcntt`iththatofplantation.Itis\'cry't'aluabIctostud}'thcstcmfonnforn1orcac-knot`lcdgcabouttl1ctrccd)-nan1icsofnaturalKorcanpinc.n1crcl1asbccnconsidcrabIcrescarchontl1cstc111for111cquationsasatoolforforcstmanagcmcnt,butitalmostbasnorclationshipt`-iththcbiologicalgrowthproccss.soitisx'ery'dimcuIttouscthccquationtoanalxrsisthcd\'amicsofstclllform.Hcrcthcdct'clopmcntofstcmformt"ascxPCctcdfornotonI\… 相似文献
84.
85.
STRAIN ELASTOGRAPHY USING DOBUTAMINE‐INDUCED CAROTID ARTERY PULSATION IN CANINE THYROID GLAND
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Gahyun Lee Sunghoon Jeon Sang‐Kwon Lee Hyunwoo Kim Dohyeon Yu Jihye Choi 《Veterinary radiology & ultrasound》2015,56(5):549-553
Thyroid disease is common in dogs and conventional ultrasonography is a standard diagnostic test for diagnosis and treatment planning. Strain elastography can provide additional information about tissue stiffness noninvasively after applying external or internal compression. However, natural carotid artery pulsations in the canine thyroid gland are too weak to maintain sufficient internal compression force. The objective of the present study was to describe the feasibility of strain elastography for evaluating the canine thyroid gland and the repeatability of dobutamine‐induced carotid artery pulsation as an internal compression method. In seven healthy Beagle dogs, strain on each thyroid lobe was induced by external compression using the ultrasound probe and internal compression using carotid artery pulsation after dobutamine infusion. The thyroid appeared homogeneously green and the subcutaneous fat superficial to the thyroid lobe appeared blue. Strain values and strain ratios did not differ among dogs or between the left and right lobes. Interobserver repeatability was excellent for both compression methods. Intraobserver repeatability of the strain ratio measured using the carotid artery pulsation method (intraclass coefficient correlation = 0.933) was higher than that measured using the external compression method (0.760). Mean strain values of thyroid lobes for the external compression method (142.93 ± 6.67) differed from the internal method (147.31 ± 8.24; P < 0.05). Strain ratios between the two methods did not differ. Strain elastography was feasible for estimating thyroid stiffness in dogs. Carotid artery pulsation induced by dobutamine infusion can be used for canine thyroid strain elastography with excellent repeatability. 相似文献
86.
Beef quality traits of heifer in comparison with steer,bull and cow at various feeding environments
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Bandugula Venkata Reddy Allur S. Sivakumar Dawoon W. Jeong Yang‐Byung Woo Sang‐June Park So‐Young Lee Ji‐Yeon Byun Chang‐Ho Kim Soo‐Hyun Cho Inho Hwang 《Animal Science Journal》2015,86(1):1-16
The present review has been focused largely on the sex type differences in beef quality among heifers, cows, steers and bulls in various feeding environments. Genetic groups, feeding systems and gender are the major factors that change carcass characteristics and fatty acid profiles of cattle. Studies identified that heifer beef has super characteristics in eating quality and a better healthy composition in fatty acids than steer, cow and bull. Diet influences the variation of fatty acid profile; particularly the level of polyunsaturated fatty acids (PUFA) interacts with breed and sex. Animals finished in pasture systems were reported to show better ratios of PUFA/ saturated fatty acids and n‐6/n‐3. Carcasses of roughage‐fed beef are lighter and have less marbling and lower quality grades but have higher cutability than carcasses of grain‐fed bulls. Heifers and cows are reported to deposit more fat than steers and bulls. Among males, lower production of testosterone by steers favors more fat thickness compared with bulls. Marbling greatly varies among cattle belonging to different sexes, and particularly, females have genetic makeup that efficiently controls deposition. The current review identified that heifers can be a premium beef brand, while steer beef currently take a large part of market share across the world. 相似文献
87.
Da Chuan Piao Tao Wang Jae Sung Lee Renato SA Vega Sang Ki Kang Yun Jaie Choi Hong Gu Lee 《畜牧与生物技术杂志(英文版)》2015,6(1)
Background
Metabolic profile was initially designed as a presymptomatic diagnostic aid based on statistical analyses of blood metabolites to provide an early warning of certain types of metabolic disorder. However, there is little metabolic profile data available about Korean Hanwoo cows. Therefore, this study aimed to determine the reference intervals of metabolic profile for Korean Hanwoo cows.Methods
Healthy animals (2,205) were selected and divided into early (day 1 to 95), middle (day 96 to 190) and late (day 191 to 285) period according to their gestating period. Metabolic profile including total protein (TP), albumin (Alb), urea (UREA), glucose (Glu), total cholesterol (T-Cho), long-chain fatty acid (LCFA), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), creatinine (Crea), calcium (Ca), inorganic phosphorous (iP) and magnesium (Mg) were analyzed using a TBA-40FR automatic biochemical analyzer. The data of Korean Hanwoo cows were then compared to those of the Japanese Wagyu cows.Results
Most of the data of the Korean Hanwoo cows were relatively higher than those of Japanese Wagyu cows, with the exception of Glu and GGT. This may indicate that the nutritional level of feed for the Korean Hanwoo cows was higher than that of the Japanese Wagyu cows because of the different feeding system. In particular, relatively higher levels of UREA and LCFA were observed in the Korean Hanwoo cows, and this may also contribute to the low reproduction efficiency.Conclusions
These findings may provide some theoretical basis for understanding the reproductive and feeding situation of Korean Hanwoo cows. 相似文献88.
Choi SW Lee SK Kim EO Oh JH Yoon KS Parris N Hicks KB Moreau RA 《Journal of agricultural and food chemistry》2007,55(10):3920-3925
The antioxidant activity of three major polyamine conjugates, N,N'-dicoumaroyl-putrescine (DCP), N-p-coumaroyl-N'-feruloylputrescine (CFP), and N,N'-diferuloyl-putrescine (DFP) isolated from corn bran, and their related hydroxycinnamic acids, p-coumaric acid and ferulic acid, were evaluated by three antioxidant in vitro assay systems, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide and hydroxyl radicals generated by enzymatic and nonenzymatic reactions. Additionally, five phenolic compounds were evaluated for melanogenesis inhibitory activity using mushroom tyrosinase and B16 melanoma cells. Most of the phenolic compounds significantly scavenged DPPH, superoxide, and hydroxyl radicals in a dose-dependent manner. Particularly, DFP showed potent DPPH (IC50 = 38.46 microM) and superoxide (IC50 = 291.62 microM) radical scavenging activities, while DCP exhibited the strongest hydroxyl radical scavenging activity (IC50 = 120.55 microM). CFP also exerted moderate DPPH, superoxide, and hydroxyl radical scavenging activities. Meanwhile, DCP (IC50 = 181.73 microM) showed potent tyrosinase inhibitory activity toward l-tyrosine as the substrate, whereas DFP (IC50 = 733.64 microM) significantly inhibited melanin synthesis in B16 melanoma cells. These current results indicate that these three polyamine conjugates from corn bran may be useful potential sources of natural antioxidants and skin-whitening agents. 相似文献
89.
Yoo HH Lee M Chung HJ Lee SK Kim DH 《Journal of agricultural and food chemistry》2007,55(18):7620-7625
The effects of citrus flavonoids on P-glycoprotein (P-gp)-mediated drug efflux were examined in human intestinal Caco-2 cells. The cellular accumulation of rhodamine-123 was measured using 10 citrus flavonoids for preliminary screening. Among the flavonoids tested, diosmin significantly increased the accumulation of rhodamine-123 in Caco-2 cells. In the bidirectional transport of digoxin, diosmin increased the apical-to-basal (A-to-B) transport but decreased the basal-to-apical (B-to-A) transport in both concentration- and time-dependent manners. The digoxin transport ratio (B-A/A-B) was estimated to be 2.3 at a concentration of 50 microM of diosmin, which was significantly lower than the 15.2 found in the control. The apparent Ki values for P(app,A-B) and P(app,B-A) were 16.1 and 5.7 microM, respectively. These results demonstrated that diosmin effectively inhibited the P-gp-mediated efflux in Caco-2 cells. Diosmin is one of the main components in citrus fruits, and the intake of food supplements containing this compound may potentially increase the absorption of drugs able to act as P-gp substrates. The clinical relevance of this interaction should be further evaluated using in vivo experiments. 相似文献
90.
为了研究矮杆油菜种质群体的主要农艺性状之间的相互关系,提高矮杆油菜品种的选育效率。对214份矮杆甘蓝型油菜材料的10个农艺性状进行相关性分析和主成分分析。结果表明:相关性分析显示株高与产量、有效分枝高度、主花序长度、主花序角果数呈正相关,单株产量与株高、一次分枝数、主花序长度和主花序角果数之间呈极显著正相关;主成分分析农艺性状综合为株高因子、角果密度因子、千粒重因子、有效分枝高度因子和每角粒数因子,累计贡献率达80.42%,涵盖了主要农艺性状的全部信息。 相似文献