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111.
Sun P  Yu HH  Zhao XQ  Wang DH 《动物学研究》2011,32(5):561-565
行为是反映动物应对环境变化的最直接形式。动物可以根据周围环境条件的变化以及自身的生理状况来调整行为,异地放养是保护珍稀动物的有效方法,但必然会对其行为产生影响。为了探讨藏羚(Pantholops hodgsonii)对异地环境的行为学适应,对异地圈养藏羚的警戒行为进行了不同季节间的比较研究,采用全事件记录法和焦点动物取样法,记录和统计了异地圈养藏羚在冷季和暖季的警戒行为,进而推测其对人类干扰的行为适应性。研究结果表明,雌性和雄性藏羚的警戒时间及警戒比例(警戒时间占全天活动时间的比例)在暖季存在显著差异(警戒时间:Z=4.36,P<0.05;警戒比例:Z=4.559,P<0.05),而在冷季则无差异(警戒时间:Z=0.001,P>0.05;警戒比例:Z=0.0014,P>0.05);而季节差异对雌、雄性藏羚的警戒时间、警戒比例均具有极显著的影响(雄性-警戒时间:F=31.758,P<0.01;警戒比例:F=21.768,P<0.01;雌性-警戒时间:F=14.98,P<0.01;警戒比例:F=11.05,P<0.01);但是季节和性别对藏羚警戒行为的影响没有交互作用(Z=?0.576,P>0.05)。这些结果提示异地圈养藏羚警戒行为的变化可能是对陌生环境适应的结果。  相似文献   
112.
一个新的忽地笑O-甲基转移酶基因的克隆与原核表达   总被引:1,自引:0,他引:1  
采用RACE技术克隆得到一个新的忽地笑O-甲基转移酶(OMT)基因,命名为LaOMT。LaOMT的cDNA序列为1379 bp,开放阅读框1077 bp,预测编码蛋白包含358个氨基酸。序列比对分析发现, LaOMT编码的蛋白序列具有依赖于S-腺苷-L-甲硫氨酸(SAM)的高度保守的结构域,与葡萄、大豆等其他植物OMTs蛋白的相似性为50%左右。将LaOMT基因连接到原核表达载体pET28a上,转化大肠杆菌Rosetta (DE3)的SDS-PAGE电泳结果显示,重组蛋白受异丙基硫代半乳糖苷(IPTG)诱导表达,分子量大小约为45 kDa,与已报导的其他植物的OMTs蛋白大小基本一致。此外,半定量RT-PCR分析结果表明, LaOMT在忽地笑的叶、鳞茎、根和花中均有表达,其中花中的表达量最低。  相似文献   
113.
为探究苯丙氨酸、酪氨酸和酪胺3种前体物对石蒜悬浮细胞系生长和生物碱积累的影响。通过向培养基添加不同浓度的3种前体物,以及同时添加苯丙氨酸和酪氨酸,考察其对细胞生长量及细胞中生物碱累积的影响。结果表明:苯丙氨酸对细胞的生长和生物碱的积累影响不明显;酪氨酸和酪胺作用显著:添加200μmol/L酪氨酸,细胞中生物碱的含量是对照组的2.56倍,其中力可拉敏和加兰他敏含量为3.77 mg/g和4.46 mg/g,分别是对照组的6.61倍和6.97倍;添加200μmol/L酪胺,细胞中生物碱含量是对照组的2.63倍,力可拉敏和加兰他敏含量为4.45 mg/g和5.14 mg/g分别是对照组的9.08倍和9.18倍;在200μmol/L酪氨酸的基础上添加苯丙氨酸没有明显的增效作用。表明添加酪氨酸和酪胺对细胞生长及生物碱生物合成具有显著的促进作用  相似文献   
114.
《Cytotherapy》2014,16(4):454-459
Background aimsTo obtain a cell product competent for clinical use in terms of cell dose and biologic properties, bone marrow-derived mesenchymal stem cells (MSCs) must be expanded ex vivo.MethodsA retrospective analysis was performed of records of 76 autologous MSC products used in phase I or II clinical studies performed in a cohort of cardiovascular patients. In all cases, native MSCs present in patient bone marrow aspirates were separated and expanded ex vivo.ResultsThe cell products were classified in two groups (A and B), according to biologic properties and expansion time (ex vivo passages) to reach the protocol-established cell dose. In group A, the population of adherent cells obtained during the expansion period (2 ± 1 passages) was composed entirely of MSCs and met the requirements of cell number and biologic features as established in the respective clinical protocol. In group B, in addition to MSCs, we observed during expansion a high proportion of ancillary cells, characterized as osteoclast precursor cells. In this case, although the biologic properties of the resulting MSC product were not affected, the yield of MSCs was significantly lower. The expansion cycles had to be increased (3 ± 1 passages).ConclusionsThese results suggest that the presence of osteoclast precursor cells in bone marrow aspirates may impose a limit for the proper clinical use of ex vivo expanded autologous bone marrow-derived MSCs.  相似文献   
115.
The mouse accessory olfactory system (AOS) is a specialized sensory pathway for detecting nonvolatile social odors, pheromones, and kairomones. The first neural circuit in the AOS pathway, called the accessory olfactory bulb (AOB), plays an important role in establishing sex-typical behaviors such as territorial aggression and mating. This small (<1 mm3) circuit possesses the capacity to distinguish unique behavioral states, such as sex, strain, and stress from chemosensory cues in the secretions and excretions of conspecifics. While the compact organization of this system presents unique opportunities for recording from large portions of the circuit simultaneously, investigation of sensory processing in the AOB remains challenging, largely due to its experimentally disadvantageous location in the brain. Here, we demonstrate a multi-stage dissection that removes the intact AOB inside a single hemisphere of the anterior mouse skull, leaving connections to both the peripheral vomeronasal sensory neurons (VSNs) and local neuronal circuitry intact. The procedure exposes the AOB surface to direct visual inspection, facilitating electrophysiological and optical recordings from AOB circuit elements in the absence of anesthetics. Upon inserting a thin cannula into the vomeronasal organ (VNO), which houses the VSNs, one can directly expose the periphery to social odors and pheromones while recording downstream activity in the AOB. This procedure enables controlled inquiries into AOS information processing, which can shed light on mechanisms linking pheromone exposure to changes in behavior.  相似文献   
116.
This article describes the removal of heavy metals from contaminated clayey soils by soil washing using various extractants. Two clayey soils, kaolin, a low buffering soil with pH of 5, and glacial till, a high buffering soil with pH of 8, were used to represent various soil conditions. These soils were spiked with chromium (Cr), nickel (Ni), and cadmium (Cd) to simulate improper disposal of typical electroplating waste constituents. The following extracting solutions were investigated for the removal of heavy metals from the soils: deionized water, distilled water, and tap water; acetic acid and phosphoric acid; chelating agents ethylenediaminetetraacetic acid (EDTA) and citric acid; and the oxidizing agents potassium permanganate and hydrogen peroxide. The effect of extractant concentration on removal of heavy metals was also investigated. Complete removal of Cr was achieved using 0.1?M potassium permanganate for kaolin, while a maximum of 54% was removed from glacial till. A maximum Ni removal of 80% was achieved using tapwater for kaolin, while a maximum removal of 48 to 52% was achieved using either 1?M acetic acid or 0.1?M citric acid for glacial till. A maximum Cd removal of 50% was achieved using any of the extractants for kaolin, while a maximum removal of 45 to 48% was obtained using either acids or chelating agents for glacial till. Overall, this study showed that complete removal of Cr, Ni, and Cd from clayey soils is difficult to achieve using the soil-washing process, and also the use of one extractant may not be effective in removing all metals. A sequential extraction using different extractants may be needed for the removal of multiple metal contaminants from clayey soils.  相似文献   
117.
典型极小种群野生植物保护与恢复技术研究   总被引:2,自引:0,他引:2  
极小种群野生植物是急需优先抢救的国家重点保护濒危植物。目前,有关极小种群野生植物濒危原因及相应解濒技术的研究还非常缺乏,已有的植物种群生态学和保护生物学理论对极小种群植物并不完全适用,迫切需要研发有针对性的科学理论和保育技术。介绍了国家重点研发计划项目"典型极小种群野生植物保护与恢复技术研究(2016YFC0503100)"的研究意义、内容、目标及展望。项目拟针对典型极小种群野生植物开展保护与恢复技术的研究,拟构建极小种群野生植物的种群生态学和保护生物学理论体系,研发极小种群野生植物保护和更新复壮的技术体系,并建立相应的应用技术标准和示范基地,为极小种群野生植物的保护与可持续利用奠定坚实的理论基础和技术支撑。  相似文献   
118.
促进铁皮石斛试管苗移栽成活的研究   总被引:8,自引:0,他引:8  
目的有效加速铁皮石斛试管苗的人工繁殖.方法:对铁皮石斛试管苗在移植时期进行不同基质(有无伴生植被)、根长和营养液浓度等方面的研究.结果:最适宜的基质是1/3泥炭 1/3锯末 1/3珍珠岩,覆以苔藓类伴生植被可大大提高移栽成活率.组培苗根长在0.5~1.0 cm时是移植的最佳时期,移植半个月后施放1/2倍营养液为最好.结论:对铁皮石斛中药的GAP种植具有重要的指导意义.  相似文献   
119.
The present work introduces for the first time a nanoparticulate approach for ex vivo monitoring of acetylcholinesterase‐catalyzed hydrolysis of endogenous acetylcholine released from nerve varicosities in mice atria. Amino‐modified 20‐nm size silica nanoparticles (SNs) doped by luminescent Tb(III) complexes were applied as the nanosensors. Their sensing capacity results from the decreased intensity of Tb(III)‐centred luminescence due to the quenching effect of acetic acid derived from acetylcholinesterase‐catalyzed hydrolysis of acetylcholine. Sensitivity of the SNs in monitoring acetylcholine hydrolysis was confirmed by in vitro experiments. Isolated atria were exposed to the nanosensors for 10 min to stain cell membranes. Acetylcholine hydrolysis was monitored optically in the atria samples by measuring quenching of Tb(III)‐centred luminescence by acetic acid derived from endogenous acetylcholine due to its acetylcholinesterase‐catalyzed hydrolysis. The reliability of the sensing was demonstrated by the quenching effect of exogenous acetylcholine added to the bath solution. Additionally, no luminescence quenching occurred when the atria were pre‐treated with the acetylcholinesterase inhibitor paraoxon.  相似文献   
120.
Macrophages secrete endoplasmic reticulum aminopeptidase 1 (ERAP1) in response to lipopolysaccharide (LPS) and interferon (IFN)-γ to enhance their phagocytic and nitric oxide (NO) synthetic activities. In this study, we found that a subset of secreted ERAP1 bound to exosomes released from LPS/IFN-γ-treated murine RAW264.7 macrophages compared to untreated cells. ERAP1-bound exosomes enhanced phagocytic and NO synthetic activities of macrophages more efficiently than free ERAP1 and exosomes derived from untreated cells. Deletion of the exon 10 coding sequence in ERAP1 gene resulted in loss of binding to exosomes. By comparing the activities of exosomes derived from wild-type and ERAP1 gene-deficient RAW264.7 cells, we observed that ERAP1 contributed to the exosome-dependent phagocytosis and NO synthesis of the cells. Upon stimulation of RAW264.7 cells with LPS/IFN-γ, TNF-α, IFN-γ, and CCL3 were also associated with the released exosomes. Analyses of cytokine function revealed that while CCL3 in the exosomes was crucial to the phagocytic activity of RAW264.7 cells, TNF-α and IFN-γ primarily contributed to the enhancement of NO synthesis. These results suggest that treatment with LPS/IFN-γ alters the physicochemical properties of exosomes released from macrophages in order to facilitate association with ERAP1 and several cytokines/chemokines. This leads to exosome-mediated enhancement of macrophage functions. It is possible that packaging effector molecules into exosomes upon inflammatory stimuli, facilitates the exertion of effective pathophysiological functions on macrophages. Our data provide the first evidence that ERAP1 associated with exosomes plays important roles in inflammatory processes via activation of macrophages.  相似文献   
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