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981.
通过CO2加富、高温处理,对温室嫁接黄瓜幼苗的细胞膜透性及保护酶活性等内在生理指标进行测定分析,旨在为黄瓜抗热高产的理论提供理论依据。结果表明,经高温处理,嫁接黄瓜幼苗的质膜透性、脯氨酸(Pro)、丙二醛(MDA)含量明显增加,且高于对照,差异极显著;超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性均呈先增后减变化趋势,变化极明显。CO2加富、高温处理,嫁接黄瓜幼苗的质膜透性、Pro、MDA含量均呈先增后减的趋势,在处理第6天低于对照;SOD、POD、CAT活性均呈上升趋势,且比高温处理要强。CO2加富、常温处理,温室嫁接黄瓜幼苗的质膜透性、Pro、MDA含量均低于对照,SOD、POD、CAT活性均高于对照,且低于高温处理。说明增加CO2浓度,有效地减弱了高温对嫁接黄瓜幼苗叶片引起的伤害,提高了嫁接黄瓜植株防御高温的能力,对温室嫁接黄瓜耐热性具有促进作用。  相似文献   
982.
Bacterial autolysate, a down stream product of bacterial biomass grown on natural gas by mainly the methanotrophic bacteria Methylococcus capsulatus, was fed at 8% as is to broiler chickens from 1 to 35 days of age for studies of fatty acid composition, lipid oxidation and sensory quality of thigh meat stored frozen for 6 month at -18 °C or -80 °C. Lipid oxidation was measured by thiobarbituric acid reactive substances (TBARS) and volatile profile by dynamic headspace gas chromatography. Adding bacterial autolysate to diets did not affect the total content of saturated, monounsaturated or polyunsaturated fatty acids in thigh meat, but increased the levels of C14:0, C16:0, C18:0 and C16:1n-7 and reduced the levels of C18:1n-7, C18:2n-6 and C18:3n-3 fatty acids. Feeding of bacterial autolysate tended (p < 0.08) to reduce TBARS of meat samples. Contents of volatiles were generally low, but feeding of bacterial autolysate significantly reduced levels of butanal (p < 0.04) and tended to reduce levels of hexanal (p < 0.11), pentanal (p < 0.09), 1-penten-3-ol (p < 0.08) and butanone (p < 0.08). Bacterial autolysate had no effects on sensory quality parameters of meat related to odour and flavour. To conclude, adding bacterial autolysate to diets did not affect the relative proportion of saturated, monounsaturated or polyunsaturated fatty acids, but reduced content of volatiles in frozen-stored broiler meat. The reduced susceptibility to lipid oxidation in broiler meat may be related to antioxidant properties of the bacterial autolysate.  相似文献   
983.
The study investigated the effects of diet supplementation with 1% clove flower buds powder combined with either 0.2% lemon balm extract or 0.2% agrimony extract (each of the two pulverized extracts supplied through drinking water) on body weight of broilers, total feed intake, feed conversion ratio and the carcass yield, activity of superoxide dismutase (SOD, EC 1.15.1.1) and glutathione peroxidase (GSH‐Px, EC 1.11.1.9) in blood, concentration of sulfhydryl (?SH) groups, malondialdehyde (MDA), vitamin A and E, low‐density lipoproteins in the blood plasma, serum cholesterol, total lipids, triglycerides and high‐density lipoproteins in broiler chickens at 42 days of age. On the day of hatching, 120 male and female broilers of Cobb 500 were randomly divided into three groups. The control group (1st group) of broilers received a basal diet (BD) without any feed and water additive. Both experimental groups of chicks were fed BD enriched with clove (Syzygium aromaticum L.) powder at a dose of 10 g/kg DM for 42 days. Moreover, either lemon balm (Mellisa officinalis L.) extract or agrimony (Agrimonia eupatoria L.) extract diluted with drinking water (2:1000) was given to broilers in the 2nd and 3rd group respectively. The results indicated that feeding the diets enriched with selected herbal supplements failed to affect the growth performance of broiler chickens at 42 days of age. In addition, this supplementation had no influence on the activities of SOD and GSH‐Px, concentration of vitamin A and selected lipid metabolism indices. On the other hand, we observed beneficial effects on some indices of the antioxidant status (increased concentration of ?SH groups and vitamin E, decreased concentration of MDA) in the blood of broilers in both experimental groups in comparison with the control group of chickens (p < 0.05). Furthermore, a slightly better antioxidant capacity was found in the blood of broilers supplied the combination of clove and lemon balm compared to clove and agrimony (vitamin E, 11.26 ± 0.73 vs. 9.73 ± 0.64 μmol/L, p < 0.05 respectively). It could be concluded that supplementation of the diet with clove flower buds powder combined with lemon balm extract or agrimony extract dissolved in drinking water has a potential to increase the antioxidant status but fails to influence either the growth performance or the selected lipid metabolism indices of broilers at the age of 42 days.  相似文献   
984.
采用正交设计从种子含水量、包装方法、保存温度和预回湿方法4个因素来探索山合欢种子超干燥保存的可行性。用硅胶将种子脱水至1.42%~6.35%6个含水量梯度,结合不同处理密封保存1年,随后测定发芽率和一些生理生化指标,包括相对电导率(RC)、脯氨酸(Pro)、丙二醛(MDA)、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、可溶性总糖含量和脂肪酸组分。结果表明:种子含水量和预回湿方法对发芽率有显著影响,超干种子与未经超干处理的种子相比,发芽率有明显提高;超干种子发芽率与相对电导率和丙二醛含量呈显著负相关,与脯氨酸含量和3种抗氧化酶活性呈显著正相关;超干种子的油酸和α-亚麻酸含量比对照提高。适宜的超干处理能使抗氧化酶活性增强,使不饱和脂肪酸和可溶性总糖的含量增加,从而减缓种子生活力下降。  相似文献   
985.
The present study was conducted to evaluate the effect of an aqueous alfalfa extract (AAE) on production performance, egg quality and lipid metabolism of laying hens between 28 and 36 weeks of age. Four groups of commercial hens (Hy-Line Brown) were fed with diets containing 0, 0.05%, 0.1% and 0.15% AAE. Dietary AAE had no effect on egg production parameters (p > 0.05). Shell strength was increased (linear and quadratic effects; p < 0.05) with gradient addition of AAE. Furthermore, shell strength was notably higher (p < 0.05) in 0.1% and 0.15% AAE groups than the control group. With an exception of serum low and high density lipoprotein cholesterol, serum total triglycerides and liver cholesterol concentration (day 42), lipid indices in yolk, serum and liver were lowered (linear and quadratic effects; p < 0.05) at day 42 and day 56 as AAE in diets increased, as well as the enzyme activities of acetyl-CoA carboxylase (ACC) and β-hydroxy-β-methylglutaryl-CoA (HMG-CoA) reductase. In relation to the control group, cholesterol and triglycerides in yolk, liver and serum and serum very low density lipoprotein cholesterol were lower in 0.15% AAE-treated birds at day 42 and day 56. It also significantly decreased activities of ACC, HMG-CoA reductase and fatty acid synthetase (FAS) at day 56. The 0.1% AAE decreased triglycerides in yolk, liver and serum, as well as the activities of ACC and FAS at day 56. These data suggest that dietary AAE could be applied to improve egg shell quality and modify the lipid status of laying hens and eggs.  相似文献   
986.
以肉鸡为动物模型,探讨了日粮中添加不同配比油脂后对其脂肪代谢的影响。648只1日龄AA肉仔鸡,随机分为6组,每组6个重复,每个重复18只鸡,试验期为42 d。CON组为对照组(饲喂基础日粮),SO组为正对照组(日粮中添加豆油),LO组为负对照组(日粮中添加猪油),COP、COC、COV组分别在日粮中添加以棕榈油为主的配比油脂、以椰子油为主的配比油脂、多种植物油配比的油脂。结果表明:42 d,各组腹脂重、皮下脂肪厚度与肌间脂肪厚度、胸肌含脂率、腿肌含脂率均无显著性差异(P>0.05);SO、COP组总甘油三酯含量低于COV组(P<0.05);COP组血清低密度脂蛋白胆固醇含量低于LO组(P<0.01)与CON组(P<0.05);COP组血清高密度脂蛋白胆固醇与低密度脂蛋白胆固醇含量的比值高于LO、COC、COV组(P<0.01),SO组显著提高(P<0.05);SO组肉鸡血清中总脂酶活性高于CON组(P<0.05),肝脏中COP、COC、COV组脂蛋白脂酶、肝脂酶与总脂酶活性都显著提高(P<0.01或P<0.05)。结论:配比油脂组与豆油组在不影响脂肪沉积的情况下,改善了肉仔鸡的体脂分布,且对脂质代谢具有很好的调节作用,其中豆油组与以棕榈油为主的配比油脂组效果较好。  相似文献   
987.
Genetically modified (GM) animals are unique mutants with an enormous scientific potential. Cryopreservation of pre-implantation embryos or spermatozoa is a common approach for protecting these lines from being lost or to store them in a repository. A mutant line can be taken out of a breeding nucleus only if sufficient numbers of samples with an appropriate level of quality are cryopreserved. The quality of different donors within the same mouse line might be heterogeneous and the cryopreservation procedure might also be error-prone. However, only limited amounts of material are available for analysis. To improve the monitoring of frozen/thawed spermatozoa, commonly used in vitro fertilization (IVF) followed by embryo transfer were replaced with animal-free techniques. Major factors for assessing spermatozoa quality (i.e., density, viability, motility, and morphology) were evaluated by fluorescence microscopy. For this, a live/dead cell staining protocol requiring only small amounts of material was created. Membrane integrity was then examined as major parameter closely correlated with successful IVF. These complex analyses allow us to monitor frozen/thawed spermatozoa from GM mice using a relatively simple staining procedure. This approach leads to a reduction of animal experiments and contributes to the 3R principles (replacement, reduction and refinement of animal experiments).  相似文献   
988.
An 8-year-old neutered female British Blue cat was presented with a presumed diagnosis of a prolapsed nictitans gland and associated ocular irritation and epiphora. However, during surgery, the apparent nictitans gland protrusion was determined to be an everted cartilage of the nictitating membrane. The scrolled portion of the cartilage was removed through an incision through the conjunctiva on the bulbar aspect of the third eyelid, as previously described in the dog. This operation resolved the ocular irritation occurring, and the third eyelid returned to its anatomically correct position.  相似文献   
989.
990.
生长动物脂肪代谢关键酶基因表达调控   总被引:5,自引:1,他引:4  
动物体内脂肪组织合成与分解代谢的调控主要是通过调控脂肪代谢关键酶的含量和活性来进行的。关键酶的基因表达水平决定了酶蛋白的多寡和活性的高低。本文对脂肪代谢中的脂肪酸合成酶(FAS)、乙酰辅酶 A羧化酶(ACC)、激素敏感酯酶(HSL)、脂蛋白酯酶(LPL)的活性及其相应的基因表达水平影响脂肪代谢的研究进展进行综述。  相似文献   
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