全文获取类型
收费全文 | 69篇 |
免费 | 3篇 |
国内免费 | 19篇 |
专业分类
林业 | 3篇 |
农学 | 13篇 |
2篇 | |
综合类 | 36篇 |
农作物 | 9篇 |
水产渔业 | 1篇 |
畜牧兽医 | 22篇 |
园艺 | 5篇 |
出版年
2023年 | 2篇 |
2021年 | 2篇 |
2019年 | 3篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 2篇 |
2015年 | 2篇 |
2014年 | 1篇 |
2013年 | 4篇 |
2012年 | 4篇 |
2011年 | 4篇 |
2010年 | 5篇 |
2009年 | 5篇 |
2008年 | 6篇 |
2007年 | 9篇 |
2006年 | 2篇 |
2005年 | 8篇 |
2004年 | 4篇 |
2003年 | 4篇 |
2002年 | 7篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 4篇 |
1997年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有91条查询结果,搜索用时 15 毫秒
81.
甜菜碱对肉用型种鸡生产性能的影响 总被引:1,自引:0,他引:1
将90只37周龄AA父母代种母鸡随机分为3组,每组30只,1组为对照组,饲喂玉米—豆粕型基础日粮,2组和3组为试验组,分别饲喂含甜菜碱100毫克/千克和200毫克/千克的基础日粮7周,限制饲养。测定每组鸡的产蛋率、平均蛋重、料蛋比和种蛋孵化率。结果表明:2组的产蛋率分别比1组和3组提高8.17和6.6个百分点(P<0.01),2组和3组的耗料分别比对照组降低2.4%和6.1%,3组的入孵蛋孵化率比1组提高5.9个百分点(P<0.05),平均蛋重三组间差异不显著 相似文献
82.
83.
LIU Guang-jie LIU Guang-ze LAN Dan CHEN Mei-juan LIAO Han-xiong LIU Hai-xia ZOU Qing-yan 《园艺学报》2013,29(6):1114-1118
AIM: To evaluate the effect of betaine on lipid metabolism disorder in inherited db/db mice with long-term nonalcoholic fatty liver disease (NAFLD).METHODS: Experimental NAFLD models were established by feeding the db/db mice with high-fat diet. Fifty 7-month-old db/db mice were randomly divided into 5 groups: the mice in low, medium and high dose groups were given betaine by intragastric administration at doses of 200 mg/kg, 400 mg/kg and 800 mg/kg for 6 weeks, respectively,while the mice in saline control group and positive drug group were given normal saline and positive control drug,respctively. All the animals were killed, and serum alanine aminotransferase (ALT), triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL) and glucose tolerance were detected. The pathological changes of the liver tissues were also observed.RESULTS: Betaine significantly decreased the levels of ALT, TC and LDL (P<0.05 or P<0.01). The pathological changes of the liver tissues indicated that the content of lipid in the hepatocytes of betaine treatment groups was less than that in saline control group.CONCLUSION: Betaine significantly improves the lipid metabolism and the liver function in the aging db/db mice, and reduces the accumulation of lipid in the hepatocytes. 相似文献
84.
[目的]研究盐胁迫下外源甜菜碱对番茄幼苗光合作用的影响。[方法]以番茄中杂101号为试验材料,用不同浓度(5.0、10.0、20.0、50.0mmol/L)甜菜碱处理番茄幼苗,以营养液为对照,测定番茄幼苗叶绿素含量和光合作用参数的变化。[结果]结果表明:在盐胁迫下,外源甜菜碱能使叶片叶绿素含量和叶绿素a荧光诱导动力学参数Fv/Fo、Fv/Fm增高,从而减轻盐胁迫对幼苗的抑制作用,并且甜菜碱浓度以5.0 mmol/L效果更好。[结论]根施外源甜菜碱具有增强番茄幼苗抗盐性的作用。 相似文献
85.
以转甜菜碱醛脱氢酶(betaine aldehyde dehydrogenase)基因(BADH)大豆、非转基因亲本‘黑农35’、野生大豆、当地栽培种‘抗线王’、耐盐碱性较差品种‘合丰50’等5种大豆品种为材料,在典型盐碱土封闭种植,于大豆苗期、花荚期、鼓粒期和成熟期取根际土,采用经典方法测定氮素转化过程相关的细菌数量、生化功能及速效氮含量等指标的动态变化,为揭示转BADH基因大豆对土壤氮素转化的影响机制提供理论支持。结果表明:与非转基因亲本相比,转BADH基因大豆对苗期和花荚期根际土壤固氮菌数量有促进作用,但抑制苗期和花荚期根际土壤氨化细菌数量,对硝化细菌数量无显著性影响;显著促进成熟期大豆根际土壤固氮作用强度,对大豆苗期、花荚期和鼓粒期根际土壤氨化作用强度有显著抑制作用,显著促进各生育时期硝化作用强度;转BADH基因大豆苗期和花荚期根际土壤铵态氮含量显著降低,对鼓粒期根际土壤铵态氮含量无显著性影响,成熟期根际土壤铵态氮含量显著增高,大豆苗期、鼓粒期和成熟期根际土壤硝态氮含量显著升高,花荚期根际硝态氮含量显著降低。研究结果说明,转BADH基因大豆通过调节苗期、花期根际土壤氮素转化功能菌数量和生化过程强度进而影响氮素转化。 相似文献
86.
87.
Betaine has been demonstrated to improve growth performance and antioxidant status of animals under various stress conditions. However, there is no literature on the effects of betaine in animals exposed to mycotoxins, which are among the most prevalent contaminants in feed. Therefore, this study was conducted to evaluate the influence of dietary betaine on broilers fed a diet based on mold-contaminated corn (MCC). A total of 192 Ross 308 male broiler chicks at 1 d of age were randomly divided into 4 groups with 6 replicates and fed an MCC-based diet supplemented with 0, 250, 500, and 1,000 mg/kg betaine, respectively. Betaine increased average daily gain (linear, P = 0.030) and decreased feed conversion ratio (linear, P = 0.027) of broilers during d 1 – 21, and decreased feed conversion ratio during d 22 – 42 (linear, P = 0.012; quadratic, P < 0.001) and d 1 – 42 (linear, P = 0.003; quadratic, P = 0.004), whereas feed intake was not affected. Total cholesterol (linear, P = 0.024), alanine aminotransferase (quadratic, P < 0.001) and alkaline phosphatase (linear, P = 0.007; quadratic, P = 0.025) activities in serum were decreased by betaine. Betaine linearly increased breast muscle yield (P = 0.003) and pH24 h (P = 0.008), and decreased drip loss (P = 0.022). Betaine increased (linear, P = 0.025; quadratic, P = 0.016) total superoxide dismutase activity in breast muscle and reduced malondialdehyde content in serum (linear, P = 0.006), liver (quadratic, P = 0.006) and breast muscle (linear, P = 0.003). Moreover, the zearalenone concentrations in breast muscle were linearly decreased by betaine (P = 0.006). It was concluded that betaine could improve growth performance, liver health, antioxidant status, and breast meat yield and quality, and reduce zearalenone residue in broilers fed the MCC-based diet, especially at 500 or 1,000 mg/kg. 相似文献
88.
甜菜碱替代肉鸭日粮中蛋氨酸的研究 总被引:7,自引:0,他引:7
试验选用1日龄樱桃谷肉仔鸭700只,随机分为7组,每组2个重复,每个重复50只,参试各组按甜菜碱,蛋氨酸=1:2的比例分别替代基础日粮中蛋氨酸添加量的0/6,1/7、1/3、1/2,2/3,5/6和6/6而设计,以研究甜菜碱替代肉鸭日粮中蛋氨酸对1 ̄42日龄肉鸭生产性能的效果及最佳替代水平。结果表明,在肉鸭日粮中用甜菜碱替代蛋氨酸的最佳水平为1 ̄3周龄,1/2;4 ̄6周龄,2/3。 相似文献
89.
变水处理条件下小麦幼苗的甜菜碱代谢与抗旱性的关系 总被引:16,自引:1,他引:15
在缓慢土壤水分胁迫一复水的变水处理条件下,小麦幼苗地上部分相对含水量在80%~70%时,甜菜碱含量及甜菜碱醛脱氢酶活性最高,相对含水量大于80%或小于70%,甜菜碱的含量和甜菜碱醛脱氢酶活性都降低,并且两者变化是“同步”的。水分胁迫时,小麦幼苗迅速积累甜菜碱,抗旱型小麦增加6~8倍,水分敏感型增加4倍。积累甜菜碱与 相似文献
90.
Yinzhao Zhong Zhaoming Yan Bo Song Changbing Zheng Yehui Duan Xiangfeng Kong JinPing Deng Fengna Li 《动物营养(英文)》2021,7(2):376
The objective of the study is to evaluate and compare the effects of betaine or glycine on carcass trait, meat quality and lipid metabolism of finishing Huan Jiang mini-pigs. Betaine called trimethylglycine is a methyl derivative of glycine, but few researches were conducted to compare the impact of dietary betaine and glycine on pigs. One hundred and forty-four Huan Jiang mini-pigs (body weight = 10.55 ± 0.15 kg; 70 d) were randomly divided to 3 treatment groups (basal diet, glycine or betaine). Results indicated that dietary betaine increased the average daily gain (ADG) and final weight (P < 0.05). Dietary glycine or betaine markedly reduced average backfat thickness (P < 0.05) and heightened lean percentage (P < 0.01) compared to the control group. Moreover, in comparison with the control group, betaine significantly improved the redness (a∗) and tenderness (shear force) of the longissimus dorsi (LD) muscle (P < 0.05), whereas glycine only raised the value of a∗ of the LD muscle (P < 0.05). These results showed that diet supplemented with 0.25% betaine and equimolar amounts of glycine could regulate cascass trait and meat quality of finishing Huan Jiang mini-pigs, and the effect of betaine was superior to that of glycine. 相似文献