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21.
4种蛋白质饲料对幼龄獭兔饲用价值的比较研究   总被引:1,自引:0,他引:1  
为了评定豆粕、玉米蛋白粉、棉粕、菜粕等4种蛋白质饲料在獭兔幼龄阶段的营养价值,试验以3月龄獭兔为研究对象,通过化学测定、消化试验与饲养试验,比较分析了4种蛋白质饲料的化学组成及其营养价值。结果显示:粗蛋白表观可吸收量以棉粕最高,为383.22 g/kg,分别比豆粕、玉米蛋白粉、菜粕多3.4,137.9,20.85 g/kg;必需氨基酸化学值指数(EAAI)与可吸收量指数均以菜粕最高,分别为1.18,0.047 5;干物质表观消化能以豆粕最高,为9.99 MJ/kg,分别比玉米蛋白粉、棉粕、菜粕高2.94,3.20,2.68 MJ/kg;豆粕的钙消化吸收最佳,消化率与表观吸收量分别为79.32%,18.59 g/kg,极显著高于棉粕,显著高于菜粕;玉米蛋白粉的磷消化吸收最佳,消化率与表观吸收量分别为63.82%,6.14 g/kg,极显著高于棉粕,显著高于菜粕;4个处理的日均增重、日均采食量、料重比均无显著差异,以棉粕组日均增重最大,为26.64 g。棉粕可用作3月龄獭兔的蛋白质饲料。  相似文献   
22.
李丽霞 《安徽农业科学》2011,39(30):18684-18686
[目的]应用生长抑素(somatostatin,SS)抗血清研究七彩山鸡(Phasianus colchicas)胃肠道SS免疫活性细胞的分布密度和形态,并探讨其分布型的成因及细胞形态与功能的关系。[方法]采用免疫组织化学方法进行试验。[结果]SS细胞在腺胃及十二指肠以下都有分布。在回肠分布密度最高,空肠和十二指肠较高,盲肠和腺胃次之,直肠很少。SS细胞的型态多样,呈圆形、椭圆形、锥体形等,主要分布于胃肠固有膜、黏膜上皮细胞之间、黏膜上皮细胞基部、腺泡上皮细胞之间。[结论]七彩山鸡胃肠道SS细胞分布型的形成与各部位消化功能有关,根据形态,认为七彩山鸡胃肠道SS细胞具有内、外分泌两种功能。  相似文献   
23.
Juvenile tilapias (Oreochromis niloticus × O. aureus), with average body weights of groups I, II and III of 55.14, 122.82, and 225.68 g respectively were used to study changes in the activity of protease, amylase, and lipase in different organs and sections of the alimentary tract. Additionally, tract containing digesta, which is closer to physiological conditions, may help reveal the mechanisms of whole chemical digestion process. Another group of tilapias (mean body weight of 111.81 ± 0.14 g) was used to analyze changes in activity of protease, lipase, and amylase in response to varying pH and temperatures. The activity of enzymes in all digestive organs increased when body weight increased from 55 to 122 g, and the activity further increased when the weights increased from 122 to 225 g. The rates of increase in digestive enzyme activity were significantly greater than the rates of growth of the fish. When the activity was compared in different sections of the tract, a similar regularity was found for the three enzymes in all fish. The highest amounts of activity were seen in the foregut and the lowest in the rectum, with the middle amount of activity in the hindgut. The pH ranges for the maximum activity of tilapia protease in the stomach and intestine were 1.6–3.3 and 9.5–10.5 respectively and the optimal temperature in these organs was 55°C. The pH ranges for the maximum amylase activity in the intestine and hepatopancreas were 6–7 and 7.5 respectively, and high amylase activity in these organs was found at 25–35°C. The activity of lipase in the intestine remained unchanged at pH 6.0–9.0 and with temperatures between 25 and 35°C. These results suggest that the ability of tilapia to utilize feed varies at different growth stages and remains relatively stable with changes in environmental pH and temperature, which should be taken into account when designing feed formulas for tilapia.  相似文献   
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25.
海鳗消化道的显微结构   总被引:8,自引:1,他引:8       下载免费PDF全文
采用大体解剖和光镜技术研究了海鳗(Muraenesax cinereius)消化道形态学和组织学。海鳗消化道分化为明显的食道、胃和肠。食道皱襞多且粗大,黏膜为复层上皮,部分区域为单层柱状上皮。上皮中含两种类型的杯状细胞,以杯状细胞层次多为显著特征,此外还有嗜酸性细胞。肌层厚。浆膜中纤维发达,伸人肌层并与黏膜下层相连。胃“Y”形,分为贲门部、盲囊部和幽门部,盲囊部发达。胃上皮为单层柱状上皮,贲门部和盲囊部胃腺发达,至幽门部胃腺逐渐消失。肠短,由具微绒毛的单层柱状上皮构成,小肠前段绒毛分支多且相互吻合,毛细血管丰富,平滑肌多。直肠单层柱状上皮与假复层纤毛柱状上皮共存。海鳗消化道组织结构特点反映了其凶猛、食肉、食量大的食性特点。  相似文献   
26.
本文通过组织解剖与切片法测量了鲤、草、鲢、鳙的相关生物学参数,系统观察了四种鱼的消化道肌肉层、肠绒毛以及粘液细胞的显微结构及分布特点,探究其与食性的相互关系。结果显示:鲤比肠长1.0,环行肌较纵行肌发达,肠绒毛丰富,粘液细胞均匀分布在整个消化道中;草鱼比肠长2.13,消化道组织结构均一,肌肉壁中纵行肌所占比例高,粘液细胞体积小,分散于整个消化道中,肠绒毛极发达;鲢比肠长8.49,环行肌极发达,粘液细胞集中于消化道前段,肠绒毛由前至后逐渐呈短粗状;鳙比肠长4.58,环行肌极为发达,粘液细胞数量多且均匀地分布于消化道前、中段,肠绒毛较为稀疏短粗,粘液细胞较少。这四种鱼消化道的组织结构特征与各自食性密切相关。  相似文献   
27.
The gastrointestinal (GI) tract of an animal consists of a very complex and dynamic microbial ecosystem that is very important from a nutritional, physiological and pathological point of view. A wide range of microbes derived from the surrounding aquatic environment, soil/sediment and feed are found to colonize in the GI tract of fish. Among the microbial groups, bacteria (aerobic, facultative anaerobic and obligate aneraobic forms) are the principal colonizers in the GI tract of fish, and in some fish, yeasts are also reported. The common bacterial colonizers in the GI tract of freshwater and marine fish include Vibrio, Aeromonas, Flavobacterium, Plesiomonas, Pseudomonas, Enterobacteriaceae, Micrococcus, Acinetobacter, Clostridium, Fusarium and Bacteroides, which may vary from species to species as well as environmental conditions. Besides, several unknown bacteria belonging to Mycoplasma, Arthrobacter, Brochothrix, Jeotgailbacillus, Ochrobactrum, Psychrobacter and Sejongia species in the GI tract of different fish species have now been identified successfully using culture‐independent techniques. Gnotobiotic and conventional studies indicate the involvement of GI microbiota in fish nutrition, epithelial development, immunity as well as disease outbreak. This review also highlights the need for manipulating the gut microbiota with useful beneficial microbes through probiotic, prebiotic and synbiotic concepts for better fish health management.  相似文献   
28.
试验利用植物源乳酸菌,对断奶仔猪日粮中养分表观消化率及消化道内容物特性的影响进行了研究。结果表明,仔猪日粮中添加植物源乳酸菌可分别提高干物质、粗蛋白、能量、粗脂肪、钙、磷等的表观消化率;降低消化道pH,增加肠道乳酸菌的数量,可弥补仔猪胃酸分泌不足。同时,还可减少消化道盲肠和结肠内大肠杆菌的数量,改善动物消化道微生态平衡。  相似文献   
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Background: Despite frequent clinical use, information about the pharmacokinetics and efficacy of pantoprazole in camelids is not available. Objectives: To examine the pharmacokinetics of both IV and SC pantoprazole and to determine whether pantoprazole administration would increase 3rd compartment pH in alpacas. Animals: Six healthy adult alpacas. Methods: Alpacas were fitted with a 3rd compartment cannula for measuring gastric pH. After recovery, alpacas received 1 mg/kg pantoprazole IV, q24h for 3 days or 2 mg/kg SC q24h for 3 days. Alpacas received both IV and SC pantoprazole, with a minimum of 3 weeks between treatments. Third compartment pH was recorded and plasma samples were taken for pharmacokinetic analysis. Results: Pantoprazole induced a slow but sustained increase in 3rd compartment pH when given by both the IV and SC routes. Third compartment pH was significantly increased as compared with baseline values (1.81 ± 0.7; mean ± SD) at 24 (2.47 ± 0.8), 48 (3.53 ± 1.0) and 72 hours (4.03 ± 1.3) after daily IV administration of pantoprazole. Third compartment pH increased from 1.73 ± 0.6 at baseline to 3.05 ± 1.1, 4.02 ± 1.4, and 3.61 ± 1.6 at 24, 48, and 72 hours after SC administration, respectively. Pharmacokinetic analysis demonstrated that pantoprazole had a short elimination half‐life (0.47 + 0.06 h) and a high clearance rate (12.2 ± 2.9 mL/kg/min) after both IV and SC administration. Conclusions and Clinical Relevance: Based on the results of this study, pantoprazole represents a safe and effective drug for increasing 3rd compartment pH in camelids. Either IV or SC administration is likely to be an effective treatment for gastric ulcers.  相似文献   
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