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1.
为丰富花生种子特异启动子资源,本研究利用PCR技术在花生基因组中克隆了种子贮藏蛋白基因PSC32的启动子AHSSP1,利用半定量RT-PCR检测了PSC32基因表达模式,借助NewPLACE在线分析了AHSSP1序列中存在的顺式作用元件,并构建了AHSSP1驱动GUS报告基因的表达载体,经农杆菌转化获得转基因拟南芥,经GUS组织化学染色鉴定了该启动子的功能。结果表明,PSC32基因957 bp长的启动子AHSSP1序列具备种子特异表达启动子特有的3个RY REPEAT元件。半定量RT-PCR分析发现,PSC32基因在花生成熟种子中表达,而在饱果成熟期根、茎、叶片、花、入土前的果针、成熟种子的果壳中均不表达。GUS组织化学染色发现,转基因拟南芥成熟种子以及萌发种子的子叶、下胚轴和胚根均能够被染上蓝色;长出真叶后,子叶和下胚轴仍能被染色,而根和真叶不能被染上蓝色;成年期转基因拟南芥的叶片也不能被染上蓝色。而野生型拟南芥整个生长时期均不能被染上蓝色。以上现象说明AHSSP1是一个种子特异启动子。本研究丰富了花生种子特异启动子的资源,对花生籽仁品质改良或以花生籽仁作为“生物反应器”的研究具有重要的应用价值。  相似文献   
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盾叶薯蓣中薯蓣皂苷元生物合成途径研究进展   总被引:2,自引:0,他引:2  
综述了薯蓣皂苷元生物合成途径的研究进展及相关酶的研究进展,对其生物合成途径进行了推断,以期为盾叶薯蓣皂苷元合成相关的研究以及利用生物工程进行生产奠定基础。  相似文献   
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ObjectiveTo describe and evaluate an ultrasound-guided modified subcostal approach for the transversus abdominis plane (TAP) block in horse cadavers in lateral or dorsal recumbency.Study designProspective, experimental cadaveric study.AnimalsStudy of one preserved foal and eight fresh adult horse cadavers.MethodsThe lateral and ventral abdominal wall of a preserved cadaver was dissected to identify the muscles and nerves. A unilateral standard TAP block technique was performed (60 mL of methylene blue dye–bupivacaine) on a fresh cadaver in right lateral recumbency. A modified subcostal technique was performed on the opposite side using a linear ultrasound transducer and in-plane approach. Injection points (two 30 mL dye) were at the level of the TAP (between the rectus abdominis and transversus abdominis muscles and ventral to the cutaneous trunci muscle) perpendicular to: 1) the mid-point between the xiphoid cartilage and umbilical scar; and 2) at a point between the caudal and middle thirds of the abdomen measured from the first injection point to the umbilical scar. The modified subcostal approach was performed in seven additional cadavers in both hemiabdomens, with three cadavers in lateral and four cadavers in dorsal recumbency. Ultrasound guidance was used with all injections.ResultsThe standard approach stained the sixteenth to eighteenth thoracic nerves (T16–T18). The modified subcostal approach performed in lateral recumbency provided greater spread (T9–T17) than dorsal recumbency (T12–T18) (p = 0.016).Conclusions and clinical relevanceThe modified subcostal TAP approach resulted in extensive staining exceeding the standard approach. The nerves stained are consistent with production of ventral abdominal wall anesthesia in horses. Clinical studies are needed to verify these findings.  相似文献   
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The crucian carp (Carassius carassius, L.) is a cyprinid freshwater species, whose wild‐living populations have decreased in recent years due to an increasing competition of invasive species. Several initiatives were launched, attempting to reintroduce this fish back into its native open waters, which requires the use of crucian carp fry grown under controlled conditions. However, the use of popular commercial diets results in severe developmental abnormalities. The aim of this study was to analyse the impact of feeding natural feed (Chironomidae sp. larvae) or two popular commercial diets on the skeletal development of crucian carp juveniles. Whole‐mount staining and histological methods were used in the study. Skeletal tissues of fish fed both commercial diets were demineralized and displayed a variety of deformities, such as abnormal vertebral spines and vertebral fusion, as well as a new type of deformation, which involved the action of dorsal fin pterygiophores upon the spine. Finally, a novel analytical method was proposed, which utilizes LA‐ICP‐MS for the estimation of bone mineralization. The study proved that basic commercial diets are inadequate for the rearing of crucian carp juveniles.  相似文献   
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AIM: To develop the cell model of polymer/liquid crystal and to study the effect of their elasticity on the adhesion of rat bone marrow mesenchymal stem cells (rBM-MSCs). METHODS: Using the method of solvent evaporation induced phase separation, the cell model of polymer/liquid crystal was constructed. The surface morphology and phase separation structure were determined by polarized optical microscopy (POM), scanning electron microscopy (SEM) and small angle X-ray scattering (SAXS). rBM-MSCs were separated and expanded by adherent culture. The surface markers of rBM-MSCs were detected by flow cytometry. The cells were induced to osteogenic differentiation and adipogenic differentiation for 2 weeks. After 3 passages, the cells were divided into 4 groups, including total PU control group, 10% membrane group, 30% membrane group and 50% membrane group. The cells were then incubated with rhodamine phalloidin for cytoskeleton staining and were observed under the confocal laser scanning microscope after cultured for 24 h. RESULTS: The cell model of polymer/liquid crystal was constructed successfully using the method of solvent evaporation induced phase separation. Flow cytometry results showed that the rBM-MSCs positively expressed CD29, CD44 and CD90, and negatively expressed CD34 and CD45. After stained with alizarin red S and oil red O, the calcium nodule and lipid droplets in rBM-MSCs were observed obviously. The cytoskeleton staining result indicated that the area in total PU control group, 10% membrane group and 30% membrane group were greater, and the actin microfilaments were also clearer than that in 50% membrane group. CONCLUSION: The cell model with suitable content of liquid crystal made a contribution to the rBM-MSCs' adhesion, but too much liquid crystal inhibits cell adhesion.  相似文献   
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观察并分析了荧光增白剂和偶联Alexa 488荧光素的小麦凝集素2种荧光染色方法对松杨栅锈菌( Melampsora larici-populina)无性发育不同阶段的染色效果。结果表明:偶联Alexa 488荧光素的小麦凝集素染色处理后能够较清楚地观察到锈菌的夏孢子、萌发的芽管、附着胞、气孔下囊、侵染菌丝、吸器母细胞及吸器等不同发育阶段的结构,荧光增白剂处理后不易观察到锈菌的侵染菌丝、吸器母细胞及吸器等结构。因此,偶联Alexa 488荧光素的小麦凝集素荧光染色方法可以作为研究松杨栅锈菌与寄主杨树互作的一种组织病理学方法。  相似文献   
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[目的]建立水产品中磺胺类药物残留的化学显色快速检测法。[方法]用甲醇提取水产品中的磺胺类药物残留,采用化学显色法对其进行快速检测。[结果]通过磺胺类药物残留与特定的衍生化试剂反应,形成稳定的紫红色衍生物,检测灵敏度最低可达50μg/kg。[结论]该方法检测限能满足欧盟及我国对磺胺类药物检测的需求,且能够实现水产样品中多种磺胺类药物的现场快速检测。  相似文献   
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制备大鼠局灶性脑缺血再灌注实验模型,通过N-乙酰L-半胱氨酸(NAC)预处理对脑缺血再灌注损伤的保护作用,探索脑梗死病理过程及药物治疗途径。NAC预处理21d,利用栓线法建立大鼠大脑中动脉栓塞模型,造模后24h进行神经症状评分,TTC染色,检测血浆MDA、GSH含量,观察大脑皮质细胞凋亡情况及凋亡相关蛋白Bcl-2、Bax的表达。结果显示,通过神经症状评分和TTC染色判定大鼠局灶性脑缺血实验模型建立成功。与对照组相比,NAC预处理组(100mg·kg^-1)大鼠血浆中MDA含量显著降低(P〈0.05),GSH含量显著升高(P〈0.05);NAC模型组细胞凋亡率及Bax/Bcl-2比值明显低于对照组。结果表明,NAC通过改善氧化应激状态,调控凋亡蛋白Bcl-2、Bax表达,从而对大鼠脑缺血再灌注损伤具有一定的保护作用。  相似文献   
10.
实验采用Giemsa与Wright' s两种染色方法对黑褐新糠虾血细胞进行染色,根据血细胞大小,所含颗粒与否,颗粒多少和核质比将其分型,并对各型血细胞所占比例进行统计.结果表明,通过比较Giemsa染色与Wright's染色两种方法的染色时间和效果,Wright's染色更加适合糠虾血细胞.通过染色,将黑褐新糠虾血细胞分为3种类型,它们分别为透明细胞、半颗粒细胞和颗粒细胞.它们的胞体大小依次增大,核质比依次降低.对此3种类型血细胞比例分别统计后发现,颗粒细胞所占比例最多约( 48.38%±0.05%),其次是半颗粒细胞约为(35.22%±0.04%),最少的为透明细胞约为(16.40%±0.01%).对不同浓度溶藻弧菌的感染试验发现,日本新糠虾在较短的时间内出现死亡,即48h,而黑褐新糠虾72 h出现死亡,各浓度组中日本新糠虾死亡率均高于黑褐新糠虾.黑褐新糠虾相对日本新糠虾来说,对溶藻弧菌具有较低的敏感性,可能与其血细胞中颗粒和半颗粒比例较高有关.  相似文献   
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