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61.
鲆鲽鱼营养生理研究进展   总被引:2,自引:0,他引:2  
本文综述了鲆鲽鱼类营养生理的研究进展,涉及鲆鲽鱼对蛋白质、氨基酸、脂肪、必需脂肪酸、碳水化合物、维生素和微量元素的需要量及各种营养元素的生理功能,评价饲料中各营养素缺乏和过量对鲆鲽鱼生长的影响,以及各营养素之间的相互关系。  相似文献   
62.
Reasons for performing the study: Intestinal hyperammonaemia (HA) has been infrequently reported in individual horses; however, there have been no studies describing clinical and laboratory data as well as short‐ and long‐term outcome in a larger number of cases. Objectives: To describe clinical and laboratory data and short‐ and long‐term outcome in a large group of horses with intestinal HA. Methods: Multi‐centred, retrospective study; case records of horses with HA were reviewed and any horse with a clinical or post mortem diagnosis of intestinal HA was included. Hyperammonaemia was defined as a blood ammonium (NH4+) concentration ≥60 µmol/l and horses with a diagnosis of primary hepatic disease were excluded. Relevant data were recorded and, if appropriate, data from survivors were compared to nonsurvivors to identify potential prognostic indicators. Results: Thirty‐six cases, 26 mature horses and 10 foals with intestinal HA were identified. Case histories included diarrhoea, colic and neurological signs and the most common clinical diagnosis was colitis and/or enteritis. The most common clinical and laboratory abnormalities included tachycardia, increased packed cell volume, hyperlactataemia and hyperglycaemia. Fourteen horses (39%) survived to discharge; NH4+ concentration on admission was the only parameter significantly associated with survival. All surviving horses and foals for which follow‐up information was available recovered completely and returned to their intended use without further complications. Conclusions and potential relevance: Intestinal HA occurs in mature horses and foals and can be associated with severe clinical and laboratory abnormalities; further studies are required to investigate predisposing factors and delineate possible differences in aetiologies.  相似文献   
63.
Meat quality means the characteristics such as appearance is related to palatability in fresh meat or manufactured meat, it includes meat color, meat structure, hardness, marbling, water holding capacity and so on.The physical characteristics of mutton quality determines the consumer acceptability of meat and there is a close relationship between chemical composition of mutton quality and nutrient substance.With the improvement of living standards, consumers are increasingly high demand for mutton.From quantitative to qualitative change, we need to continuously improve mutton quality.At present, the production of high quality animal products has become a hot topic.This paper is a summary of the effects of breed, gender, age, environment and feed nutrition on mutton quality, and aims to provide a scientific basis for improving of mutton quality with nutritional regulation measures.  相似文献   
64.
铬是动物必需的营养微量元素之一,近几年对铬营养的研究工作已取得了相当大进展.本文综述了铬的营养作用和铬在家禽生产中的应用效果,为进一步在动物生产中科学地应用铬提供依据.  相似文献   
65.
Pododermatitis is a worldwide problem in captive flamingos. Studies in domestic poultry showed that nutrition is a possible influencing factor for pododermatitis. Vitamin A and E, copper and zinc levels were analysed in two different diets (diet 1 = in‐house mix and diet 2 = commercial diet) and in plasma of captive greater flamingos fed these diets and compared to those of free‐ranging greater flamingos. Results were analysed with respect to type and severity of foot lesions of the individuals from the different groups. Juvenile and subadult/adult captive flamingos on diet 1 showed various types and severities of foot lesions, whereas no foot lesions were found at the time of blood sampling in juvenile captive flamingos on diet 2. Juvenile captive flamingos on diet 1 had significantly lower plasma zinc levels than juvenile captive flamingos on diet 2 and juvenile free‐ranging flamingos; data were also lower than reference ranges for flamingos, poultry and cranes. There were no significant differences in plasma vitamin A, vitamin E, copper or zinc levels between animals with different types of foot lesions or with different severity scores. Shortly after the change to diet 2 (fed to juvenile captive flamingos that did not show any foot lesion), the flooring of the outdoor water pools was covered with fine granular sand. Because both factors (nutrition and flooring) were changed during the same evaluation period, it cannot be concluded which factor contributed in what extent to the reduction of foot lesions. While it is assumed that low plasma zinc levels identified in the group of juvenile captive flamingos on diet 1 were not directly responsible for foot lesions observed in these animals, they may have played a role in altering the skin integrity of the feet and predisposing them to pododermatitis.  相似文献   
66.
双低菜籽粕在饲料中的应用   总被引:2,自引:0,他引:2  
双低菜籽粕具有高产优质的特点,其饲用品质优于普通菜籽粕,营养价值与豆粕相当,被广泛应用于饲料。为了更有效开发其对饲料业和养殖业的应用潜力,本文就双低菜籽粕的营养价值和在动物饲用方面进行的一系列的基础性研究作一简要介绍。  相似文献   
67.
密植桑园桑树营养特性的研究简报   总被引:1,自引:0,他引:1  
通过对密植桑园不同密度下不同品种桑叶营养含量分析表明,氮和可溶性糖的含量随密度提高而提高,而磷与钾的吸收则相反,同一密度下不同品种桑叶养分也有差异。  相似文献   
68.
综述了动物营养学研究方法的发展历程,即由传统动物营养学向系统动物营养学的发展,以及各学科在动物营养研究方法中的应用。  相似文献   
69.
β-葡聚糖来源广泛,主要存在于植物和微生物细胞壁中,由葡聚糖单体构成,具有多种结构,因其侧链残基种类和数量的不同而具有多种生物学功能,如通过降低炎症相关基因表达及提高免疫因子的表达发挥调节免疫的作用;通过减少脂质的产生和吸收发挥调节脂质代谢的作用;通过提高抗氧化酶、自由基、超氧阴离子的清除活性及激活Nrf2信号通路、上调抗氧化基因的表达来增强机体的抗氧化能力,发挥抗氧化作用;通过增强缺氧耐受性及提高抗氨氮应激能力、能量代谢和抗氧化酶基因的表达等发挥抗应激作用。自抗生素禁用以来,β-葡聚糖在水产动物中的研究和应用逐渐深入,β-葡聚糖在预防水产动物疾病和减少抗生素使用等方面发挥着重要作用。在水产养殖中,β-葡聚糖可通过提高消化酶活性、改善肠道结构、优化肠道菌群及增强非特异性免疫力来提高水产动物生长性能,β-葡聚糖的联合使用比添加单一种类的免疫刺激剂具有更好的免疫效果。作者就β-葡聚糖的结构特征、生物学活性、作用机制及在水产动物中的应用进行了综述,并对β-葡聚糖今后的发展方向进行了展望,为实现水产动物生态健康养殖提供材料。  相似文献   
70.
The effect of two qualities of feed on the kinetic disposition of triclabendazole (TCBZ) metabolites was investigated in sheep (n = 4) following oral administration of TCBZ at 10 mg/kg body weight. The same sheep were given sequentially two qualitatively different diets: a low-quality (LQ) diet based on wheat straw ad libitum, and a high-quality (HQ) diet based on barley+alfalfa. The triclabendazole sulphoxide (TCBZSO) and triclabendazole sulphone (TCBZSO2) concentrations were determined in blood samples taken serially from the jugular vein between 5 min and 9 days after TCBZ administration. The parent drug TCBZ was not detected in any of the samples. The quality of feed affected the kinetics of both TCBZ metabolites. The rate of appearance (Tlag and Tmax) in the jugular blood was slower and the formed amount (AUC) of TCBZSO was slightly higher when the sheep were on the LQ diet (Tlag = 7.74 h; Tmax = 27.91 h; AUC = 1042 g.h/ml) than when they were offered the HQ diet (Tlag = 1.90 h; Tmax = 16.01 h; AUC = 832.4 g.h/ml). The MRT of TCBZSO was about 40% longer with the LQ diet than with the HQ diet. Similarly, the rate of appearance of TCBZSO2 in plasma of sheep was slower when they were on the LQ diet than when they were on the HQ diet, suggesting an impairment of the hepatic enzymatic activity involved in the oxidation of TCBZSO to TCBZSO2.  相似文献   
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