首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   94篇
  免费   5篇
林业   8篇
农学   3篇
  6篇
综合类   25篇
农作物   10篇
水产渔业   9篇
畜牧兽医   33篇
园艺   2篇
植物保护   3篇
  2023年   3篇
  2022年   2篇
  2021年   7篇
  2020年   4篇
  2019年   4篇
  2018年   6篇
  2017年   5篇
  2016年   4篇
  2015年   7篇
  2014年   4篇
  2013年   7篇
  2012年   9篇
  2011年   3篇
  2010年   3篇
  2009年   3篇
  2008年   1篇
  2007年   4篇
  2006年   3篇
  2004年   2篇
  2003年   3篇
  2001年   1篇
  1999年   1篇
  1998年   6篇
  1996年   1篇
  1994年   1篇
  1993年   1篇
  1992年   2篇
  1987年   1篇
  1935年   1篇
排序方式: 共有99条查询结果,搜索用时 15 毫秒
91.
ABSTRACT

Eight plant essential oils (cardamom, cinnamon, clove, eucalyptus, lemongrass, lime, nutmeg and rosemary) were evaluated for their antimicrobial activity against three Pseudomonas species associated with microbial spoilage of refrigerated tilapia. In vitro test of the essential oils, using disc-diffusion method, showed various degrees of antimicrobial activity against the Pseudomonas species. Cinnamon essential oil (CEO) had the highest antimicrobial activity, followed by clove essential oil. The remaining essential oils showed consistently weak activity. The antimicrobial efficiency of CEO against the Pseudomonas species was confirmed by potential minimum inhibitory concentration and minimum bactericidal concentration values, ranging between 0.125 and 0.375 µL/mL and 0.250–0.500 µL/mL, respectively. The anti-Pseudomonas activity of CEO was also tested in fish extract model at refrigeration temperature. The essential oil reduced the Pseudomonas viable count in fish extract but to a lesser extent than when it was applied at the same concentrations in culture medium. The chemical composition of CEO showed that the oil contained 79.1% cinnamaldehyde, which was suggested to be responsible for its antimicrobial activity. These results revealed the potential of CEO as a promising natural antimicrobial agent that could efficiently contribute to the control of spoilage bacteria and retard microbial spoilage of fresh fish.  相似文献   
92.
野生盘羊与巴什拜羊的杂交研究   总被引:2,自引:1,他引:2  
对野生盘羊与巴什拜羊进行导入杂交,通过对带有1/2、1/4野血的杂种羔羊生长状况、肉用性能、尾型、外形体质和毛质的变化进行观察及测定,并与纯巴什拜羔羊进行了比较.研究结果表明:第一、二代杂种羔羊在胚胎期四肢生长强度比躯体强,这一点继承了盘羊的遗传特性,从初生到断奶期间躯体的生长速度和强度较好,这方面继承了巴什拜羊早期生长发育快的遗传特征,在体尺指标和外部特征上野生基因占优势,毛质和毛的颜色基因巴什拜羊占优势.研究为今后家养绵羊与野生盘羊杂交和充分利用野生动物资源,提供科学数据.  相似文献   
93.
Mycoplasma spp were isolated in pure culture from bronchoalveolar lavage specimens from three cats with clinical, cytological and radiographic signs of bron-chopneumonia or suppurative bronchitis. Predisposing factors were not identified in the first case, the second cat had oesophageal hypomotility, while the third cat had been exposed to cigarette smoke and had advanced periodontal disease. Respiratory signs resolved promptly and completely in all cases following antimicrobial therapy directed against mycoplasmas. Mycoplasma spp are possible causes of lower respiratory tract disease in cats and this should be considered when selecting empirical therapy for feline airway disease and pneumonia. In some situations mycoplasmas may behave as primary lower respiratory tract pathogens in cats.  相似文献   
94.
[目的]研究MSTN/Smad信号通路基因(MSTN,Smad2,Smad3,Smad4,TGFBR1,TGFBR2)在新生和一周龄吐鲁番黑羊羔羊不同组织的表达差异.[方法]采用实时荧光定量PCR技术RT-PCR分析MSTN/Smad信号通路基因在新生吐鲁番黑羊羔羊股二头肌,股三头肌,半腱肌,半膜肌,背最长肌,尾脂等6种不同部位组织和一周龄羔羊的肝,肺,脾,肠,心,肾等6种内脏组织的mRNA表达水平进行分析.[结果]经过内参基因校正后,其中TGFBR1基因在肺组织中没有表达以外此基因和其他的基因在股二头肌,股三头肌,半腱肌,半膜肌,背最长肌,尾脂,肝,肺,脾,肠,心,肾等不同组织中均有表达.[结论]MSTN/Smad信号通路基因在各种不同组织中均有表达,对各组织的生长发育有影响.  相似文献   
95.
We have investigated the antinociceptive activity of zerumbone (1), a natural cyclic sesquiterpene isolated from Zingiber zerumbet Smith, in acetic acid-induced abdominal writhing test and hot plate test in mice. 1 given by intraperitoneal route produced significant dose-dependent antinociceptive effect in all the test models used. In addition, the antinociceptive effect of 1 in the hot plate test was reversed by the non-selective opioid receptor antagonist naloxone, suggesting that the opioid system is involved in its analgesic mechanism of action.  相似文献   
96.
The aqueous extract of Ficus deltoidea leaves was evaluated for possible antinociceptive activity in three models of nociception, namely, acetic acid-induced abdominal writhing, formalin and hot plate test. The results of the present study showed that intraperitoneal administration of the F. deltoidea leaves aqueous extract at the dose of 1, 50 and 100 mg/kg, 30 min prior to pain induction produced significant dose-dependent antinociceptive effect in all the models used, which indicating the presence of both central and peripherally mediated activities. Furthermore, the antinociceptive effect of the extract in the formalin and hot plate test was reversed by the non-selective opioid receptor antagonist naloxone suggesting that the endogenous opioid system is involved in its analgesic mechanism of action. Thus, the present results demonstrated that F. deltoidea leaves aqueous extract contains pharmacologically active constituents which possess antinociceptive activity justifying its popular therapeutic use in treating conditions associated with the painful conditions.  相似文献   
97.
本研究旨在建立一套适用于特克塞尔×哈萨克杂交羊亲子关系的鉴定体系。试验选取11个微卫星标记位点进行组合扩增,通过优化微卫星标记位点组合的引物浓度、退火温度及反应体系等条件,建立了4组多重PCR体系,对多重PCR扩增产物采用毛细管电泳进行基因型分型,经PROSize3.0软件读取基因型分型结果,Cervus 3.0软件分析群体的遗传多样性,鉴定特克塞尔×哈萨克级进F2代(特哈级进F2)和横交F2代(特哈横交F2)的亲子关系。结果表明,特哈级进F2和特哈横交F2的等位基因数为180和140、平均等位基因数为16.364和12.727、平均观测杂合度(Ho)为0.533和0.544、平均期望杂合度(He)为0.807和0.831、平均多态信息含量(PIC)为0.783和0.803。对特哈级进F2和特哈横交F2两个品种70只候选亲本和64只候选子代的11个微卫星标记位点进行亲子关系鉴定,结果表明:当双亲基因型未知时的累积排除概率(CE-1P)为0.9995和0.9997;当单亲基因型已知时的累积排除概率(CE-2P)均达到1.0000;双亲基因型已知的累计排除概率(CEPP)均达到1.0000。说明选择的11个微卫星标记位点具有高度的多态性和较高的排除概率,适用于遗传分析和个体的亲子鉴定。利用微卫星标记建立的特克塞尔×哈萨克杂交羊亲子鉴定体系为分析绵羊群体遗传多样性和辅助育种工作提供了理论依据。  相似文献   
98.
本研究旨在探明和田多胎红羊泌乳规律,提高双羔成活率。选取6只产双羔和田多胎红羊母羊为试验动物,检测其产后1~28 d泌乳量、乳成分变化规律;测量产后第1天母羊乳房体尺指标,并与泌乳量进行相关性分析。结果显示,和田多胎红羊产后1~28 d总泌乳量为29.87 kg,平均每日泌乳量为1.07 kg,泌乳量在第1~3天上升速度最快,在第21天达到峰值1.23 kg,泌乳曲线方程为:y=537t0.477e-0.033t;乳脂、非脂乳固体、密度、乳糖、固形物、蛋白质指标在和田多胎红羊母羊产后1~3 d快速下降,7~28 d趋于稳定,且6项指标第1天与第7、14、21、28天均差异极显著(P<0.01);和田多胎红羊母羊产后第1天与第14、21、28天的泌乳量之间相关性不显著(P>0.05),产后第2天与第28天的泌乳量相关性不显著(P>0.05),其他均显著相关(P<0.05);母羊产后第1、2、3、7天泌乳量与乳房宽呈显著相关(P<0.05),母羊产后第14、21、28天泌乳量与乳房体尺指标相关性不显著(P>0.05)。以上研究结果为和田多胎红羊新类群种质特性、选育、饲料配制、羔羊早期断奶等提供理论依据。  相似文献   
99.
This study was designed to profile the metabolites of Isochrysis galbana, an indigenous and less explored microalgae species. 1H Nuclear Magnetic Resonance (NMR) spectroscopy and Liquid Chromatography-Mass Spectrometry (LCMS) were used to establish the metabolite profiles of five different extracts of this microalga, which are hexane (Hex), ethyl acetate (EtOAc), absolute ethanol (EtOH), EtOH:water 1:1 (AqE), and 100% water (Aq). Partial least square discriminant analysis (PLS–DA) of the generated profiles revealed that EtOAc and Aq extracts contain a diverse range of metabolites as compared to the other extracts with a total of twenty-one metabolites, comprising carotenoids, polyunsaturated fatty acids, and amino acids, that were putatively identified from the NMR spectra. Meanwhile, thirty-two metabolites were successfully annotated from the LCMS/MS data, ten of which (palmitic acid, oleic acid, α-linolenic acid, arachidic acid, cholesterol, DHA, DPA, fucoxanthin, astaxanthin, and pheophytin) were similar to those present in the NMR profile. Another eleven glycerophospholipids were discovered using MS/MS-based molecular network (MN) platform. The results of this study, besides providing a better understanding of I. galbana’s chemical make-up, will be of importance in exploring this species potential as a feed ingredient in the aquaculture industry.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号