Elbow room and new jewelry     

Shouse B 《Science (New York, N.Y.)》2002,295(5560):1630-1631

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American Association for the Advancement of Science annual meeting. Human gene count on the rise     

Shouse B 《Science (New York, N.Y.)》2002,295(5559):1457

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What is your diagnosis? An oval gas lucency     

Character BJ  Mackin AJ  Cantwell HD  Austin FW 《Journal of the American Veterinary Medical Association》2002,221(1):37-38

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Reproductive and productivity traits of goats grazing Acacia cyanophylla Lindl. with and without daily PEG supplementation     

N. Lassoued  M. Rekik  H. Ben Salem  M.A. Dargouth 《Livestock Science》2006,105(1-3):129-136

A grazing experiment, conducted for 90 days compared the effect of polyethylene glycol (PEG) supplementation on postpartum reproductive traits and productivity of suckling goats grazing Acacia cyanophylla Lindl. A total of 54 native adult goats (34.4 ± 5.49 kg) were randomly allocated, 24 h after kidding, to 2 treatment groups balanced for age and the number of reared kids. Goats in both treatment groups designed C and PEG grazed in acacia for approximately 5 h every day and received each on daily basis 0.3 and 0.4 kg of hay and concentrate respectively. In addition, goats in treatment PEG were initially supplemented with 10 g/day of PEG and this supplement was then increased to 20 g /goat/day over the last 60 days of the trial. Goats receiving PEG tended (P > 0.05) to spend more time browsing acacia than those in treatment C. There were no treatment effects on live weight change of the goats, growth of their kids until 90 days of age or composition of their milk in terms of fat, protein and urea contents. Similar proportions of 74.1 and 77.8% of goats resumed postpartum ovulation with a mean ovulation rate of 1.50 ± 0.61 and 1.67 ± 0.47 (P > 0.05) in respectively the PEG and C treatments. PEG supplementation was associated with an increase (P < 0.05) in ovulation rate at the second postpartum ovulation occurring approximately 27 days after the application of the nutritional treatments (1.76 ± 0.60 versus 1.25 ± 0.45); 9 of the 13 goats ovulating in the PEG treatment were bearing more than one corpus lutuem in comparison to only 3 out of 12 females in the C group (P < 0.05). The likely increased availability of proteins in the PEG receiving goats could explain their higher ovulation rate.  相似文献   

不同细胞因子对水牛原始生殖细胞传代培养的影响     

黄奔 李童王志强  王晓丽杨素芳 农微汪博  石德顺 《中国兽医科技》2007,37(4):350-353

为探讨不同细胞因子对水牛原始生殖细胞（PGCs）传代培养的影响，将PGCs分别采用A、B、C、D、E、F和G共7种培养基进行培养，即A组：基础液＋10ng／mL白血病抑制因子（LIF）＋10ng／mL碱性成纤维细胞生长因子（bFGF）；B组：基础液＋20ng／mL LIF＋20ng／mL bFGF；C组：基础液＋20ng／mL LIF＋10ng／mL bFGF；D组：基础液＋20ng／mL LIF；E组：基础液＋20ng／mL LIF＋20ng／mL bFGF＋20ng／mL干细胞因子（SCF）；F组：基础液＋20ng／mL LIF＋40ng／mL bFGF＋40ng／mL SCF；G组（对照组）：基础液。将机械法分离的PGCs小集落接种到水牛胎儿成纤维细胞（BEF）饲养层上进行传代培养。结果，原代时，A、B、C、D、E和F组的克隆数目都显著高于对照组（P％0．05），其中E和F组的克隆数目显著高于A组（P〈0．05），而与B、C、D组差异均不显著（P〉0．05）；1～8代时，B、C、D、E、F组的克隆数目显著高于A组（P〈0．05）；对照组传代数仅为2代，A组为5代，而B、C、D、E和F组均为8代以上。结果表明，在传代过程中，LIF起主要作用，20ng／mL的LIF浓度可以满足水牛PGCs传代培养的需要。  相似文献   

Oral eosinophilic granulomas in tigers (Panthera tigris)--a collection of 16 cases.     

John M Sykes  Michael M Garner  Leah L Greer  Nancy P Lung  Rob L Coke  Frank Ridgley  Mitch Bush  Richard J Montali  Ben Okimoto  Robert Schmidt  Jack L Allen  Bruce A Rideout  Patricia A Pesavento  Edward C Ramsay 《Journal of zoo and wildlife medicine》2007,38(2):300-308

Oral eosinophilic granulomas were diagnosed in 16 tigers (Panthera tigris). All lesions were located on the hard or soft palate and typically consisted of flat or slightly raised circular ulcers. Histologic features of these lesions were essentially identical to those seen in oral eosinophilic granulomas of domestic cats and dogs. No clinical signs were noted in eight cases, though various degrees of inappetence, excessive salivation, and dysphagia were noted in the other eight tigers. Six cases were not treated. Treatment for the remaining 10 cases centered on corticosteroids and additional treatments included surgical removal, cryotherapy, antibiotics, and chlorpheniramine. Treatment with corticosteroids did appear to be effective in some cases, though lesions would worsen after cessation of therapy and no cases were cured. In addition, three cases developed complications possibly related to this corticosteroid therapy. The etiology of these lesions remains unknown, though an underlying allergic condition is likely.  相似文献   

有关我国农业、山区建设和自然资源问题的研究   总被引：1，自引：0，他引：1  

贲克平 《农业环境与发展》1998,15(1):12-16

本文对农业、耕地经营、山区建设和自然资源四个限制我国农业和农村发展的重大问题进行了理论剖析和战略运作的设想，以求取在上述四大领域内对我国的经济建设和环境保护有所建树。  相似文献   

家蚕微孢子虫感染家蚕对其中肠和血液蛋白酶活性影响   总被引：1，自引：0，他引：1  

龚舒聪  孙远挺  盛思佳  章彝  鲁兴萌 《蚕桑通报》2008,39(3)

本试验测定了不同浓度剂量微孢子虫感染家蚕后,家蚕中肠和血液中蛋白酶的变化.并对不同浓度剂量家蚕微孢子虫感染家蚕后对家蚕发育的影响和不同组织中所含微孢子虫孢子的浓度等作了初步的研究.从本实验中可以看出,感染不同浓度微孢子虫的家蚕,体内相同组织的微孢子虫数量存在显著差异.而感染相同浓度微孢子虫的蚕,不同组织中微孢子虫的数量也有差异,中肠的微孢子虫数量远高于其他部位.感染微孢子虫后,家蚕血液中的蛋白酶活性显著升高,中肠的蛋白酶的活性变化不显著,而感染微孢子虫的数量对血液和中肠中的蛋白酶的活性无显著影响.  相似文献   

不同退化程度高寒草甸植物物种多样性与生态系统多功能性关系     

周宸宇  杨晓渊  邵新庆  张中华  马丽  秦瑞敏  佘延娣  苏洪烨  常涛  魏晶晶  胡雪  拉本  周华坤 《草地学报》2022,30(12):3410-3422

为探究高寒草甸不同退化程度生态系统多功能性的变化,本研究综合考虑了植物物种多样性和多种生态系统功能如生产力、养分循环和固存能力、土壤涵养水分能力等,运用降维因子分析的方法计算了生态系统多功能性,综合分析了植物物种多样性与生态系统功能和多功能性间的关系。结果表明：高寒草甸退化显著降低了Margalef指数、Shannon-weiner指数、Simpson指数和Pielou指数(P<0.05),各生态系统功能趋于恶化。高寒草甸退化导致生态系统多功能性的下降,综合统计量结果为轻度退化(21.9955)＞中度退化(8.7295)＞重度退化(—30.7245)。植物物种多样性与生态系统多功能性之间均存在正相关关系,其中Simpson指数与生态系统多功能性指数拟合的结果最好,说明高寒草甸生态系统多功能性受植物物种多样性的制约。本研究可为青藏高原草地退化及恢复的过程和机理研究提供理论依据。  相似文献   

Establishment and early growth characteristics of six Paulownia genotypes for goat browse in Raleigh, NC, USA     

J. Paul Mueller  Jean-Marie Luginbuhl  Ben A. Bergmann 《Agroforestry Systems》2001,52(1):63-72

Meat goat production in the eastern USA is increasing as a result of growing demand from various ethnic groups. Because goats naturally prefer a high proportion of browse in their diets, research was initiated to investigate various silvopastoral production systems. The genus Paulownia contains several species which exhibit rapid juvenile growth and other characteristics that justify research into their potential use in meat goat feeding systems. In May 1997, six Paulownia genotypes were planted in a randomized complete block experiment with six replications. Trees were between 6 and 12 cm in height at planting. Genotypes included: P. fortunei seedlings, P. tomentosa seedlings, P. elongata seedlings and three P. elongata clones. Each 4-m wide plot contained a single row of 12 trees with an intra-row spacing of 1 m. Plant measurements included height, root collar diameter (RCD) at 3 cm above soil surface, and the number of main branches. Leaf samples were collected from all six replications for estimates of herbage quality. During 1998, trees were browsed with goats on two occasions to assess palatability of the herbage and to determine any preference for specific genotypes by the animals. Compared with seedling trees of all three species, the three P. elongata clones were taller (clones: 79.7 cm, seedlings: 55.9 cm; P < 0.01), had larger RCDs (clones: 18.4 mm, seedlings: 13.9 mm; P < 0.01) and had a higher branching frequency (clones: 4.9, seedlings: 1.5; P < 0.01) by the end of the first growing season. Mortality averaged 4.8% across all treatments and ranged between 0 and 8%. Early in the 1998 growing season before trees were browsed, P. elongata clones grew more rapidly than seedlings (clones: 116.4 cm, seedlings: 84.1 cm; P < 0.01). Estimates of herbage quality indicated favorable concentrations of energy and protein for lamina. In vitro true dry matter disappearance ranged from 85.4 (blades) to 71.5% (petioles) and crude protein from 25.1 (blades) to 4.9% (petioles). Animals readily browsed the lamina during two separate sessions, but no clear preference trends were observed among the different Paulownia genotypes.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献