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1.
分别用较高纯度的细粒棘球绦虫六钩蚴抗原和传统使用的囊液抗原对一次感染和二次感染细粒棘球绦虫六钩蚴的小鼠血清进行ELISA测定,认为寄生于不同部位的包囊刺激机体产生的抗体水平不同.同时检测早期抗体时,六钩蚴抗原比囊液抗原更具有阶段性优越性。小鼠二次感染六钩蚴后六钩蚴抗体水平得到明显加强,并推测认为一次感染产生的六钩蚴抗体可能是具有保护性的抗体。  相似文献   
2.
基于果实相关性状的桃品种初级核心种质取样策略研究   总被引:5,自引:1,他引:4  
以国家种质资源圃(北京)编目的558份桃品种的18个形态学和农艺学性状为基本数据,研究了桃品种初级核心种质构建的取样策略,包括总体取样比例的确定及取样方案的选择,以获得最佳的初级核心种质。本试验共设10%~90%9个总体取样比例;取样方案研究包括分组原则和组内取样比例的确定。结果表明,桃初级核心种质的适宜总体取样比例为10%;按品种类群分组结合多样性比例取样为构建桃初级核心种质的最佳取样方案;利用此取样策略从558份桃品种中提取56份作为核心样本,对其代表性进行检测表明所构建的初级核心种质能够很好地代表桃原始种质的遗传多样性。  相似文献   
3.
多花黑麦草品种比较试验   总被引:9,自引:2,他引:9  
通过对现行生产中常用的4个多花黑麦草品种在昆明地区的物候期、株高、草产量、生长率、净同化率等指标的规定表明,在生长初期,特高的生产性能比其余3个品种都好,但生长一段时间后,邦德的生产性能明显超过特高(P<0.05),抗锈王略高于特高(P>0.05),旺饲的生产性能最差(P<0.05)。因此,邦德是一个在生产中值得推广应用的品种。  相似文献   
4.
5.
AIM To explore the expression and mechanisms of circular RNA hsa_circ_087631 in the patients with primary biliary cholangitis (PBC). METHODS RT-qPCR was used to detect the expression of hsa_circ_087631 in PBC patients and healthy controls. Hsa-miR-346-overexpressing lentiviral vector pLenti-EF1a-EGFP-F2A-Puro-CMV-MCS was constructed and transfected into human acute T cell leukemia Jurkat cells, and then the expression levels of hsa_circ_087631, Bcl-6 mRNA and interleukin-21 (IL-21) mRNA were detected by RT-qPCR. Dual-luciferase reporter assay was performed to identify the interactions between hsa_circ_087631 and hsa-miR-346. RESULTS The expression of hsa_circ_087631 in the PBC patients was significantly increased compared with the healthy subjects. Hsa-miR-346-overexpressing lentiviral vector pLenti-EF1a-EGFP-F2A-Puro-CMV-MCS was successfully constructed. The expression of hsa-miR-346 was significantly increased after the hsa-miR-346-overexpressing lentiviral vector was transfected into the Jurkat cells, while the expression levels of hsa_circ_0087631, Bcl-6 mRNA and IL-21 mRNA were significantly decreased. After wild-type or mutant hsa_circ_087631 vector and hsa-miR-346 mimics were transfected into 293T cells, the results of dual-luciferase reporter assay showed that hsa-miR-346 significantly decreased the luciferase activity of wild-type hsa_circ_087631 (P<0.01), but the regulation did not change significantly after mutation of the predicted binding site. CONCLUSION Peripheral blood hsa_circ_087631 level is elevated in the PBC patients. The hsa_circ_087631/hsa-miR-346/Bcl-6 signaling may take effect in human T cells. Hsa-miR-346 significantly reduces the expression of hsa_circ_087631, but it may not be regulated by predicted binding sites.  相似文献   
6.
全国文化信息资源共享工程是一项系统工程,其中基层服务点的建设是它的重要组成部分,结合邗江区文化共享工程基层服务点建设与运行的实际状况,分析了基层点建设和为民服务工作中存在的问题,提出了相应的对策与设想。  相似文献   
7.
菌丝生长速度与呼吸消耗及胞外酶活性的关系   总被引:1,自引:0,他引:1  
以棉籽壳为主料,对平菇、刺芹侧耳、黄伞、灵芝、金针菇和香菇原种培养期间的菌丝生长速度、呼吸消耗及胞外酶活性的关系进行了研究。结果表明,6种食用菌的菌丝生长速度与呼吸消耗正相关,而有机物的降解速率与胞外酶活性的大小没有相关性。  相似文献   
8.
Lowbush blueberry (Vaccinium angustifolium) is a native plant that is not cultivated, but managed in areas of sufficient plant density to provide commercial yields. A cropping systems study was initiated to compare how organic and three levels of conventional (low, medium and high input) management practices affected soil properties at 12 grower fields in the lowbush blueberry barrens of Maine. The fields under organic and low‐conventional treatments did not receive any fertilizer inputs. The high and medium conventional treatment fields received optimal and reduced diammonium phosphate inputs, respectively. Three measurements of soil P (modified‐Morgan soil test, oxalate extractable and total P) showed no significant effect of management treatment on the phosphorus status of the soils. This suggests that soil P may be leaching below the 0–10 cm rooting zone which was investigated in this study. Equilibrium chemical speciation of soil/water extracts showed that gibbsite was controlling the solubility of Al in these barren soils and that P was undersaturated with respect to amorphous Al(OH)2PO4. A laboratory one‐point P sorption study showed that dissolved organic matter derived from the organic pad sampled from the study sites did not inhibit the adsorption of the added P. This suggests that addition of carbon‐rich soil amendments such as compost may not increase P bioavailability of these acidic soils with high Al (oxy)hydroxide (gibbsite) mineral content.  相似文献   
9.
Based on experience from 35 years of tillage research in Sweden, future development of soil tillage is discussed and some research problems are identified. Tillage and seeding methods must be more carefully adapted to conditions at individual sites and occasions. Low-pressure typres, better weed control and improved seed coulters favour the increased use of reduced tillage. In order to diminish the impact of agriculture on the environment, it is necessary to develop methods for establishment of crops in the early spring or immediately after harvest, even in soils with large amounts of crop residues or high moisture content. The roles of tillage methods, and of soil compaction and structure on environmental impact of agriculture must be investigated. World food production must increase, since the world population is rapidly increasing. Therefore, it is necessary to develop improved crop production systems, including crop establishment systems, which favour efficient use of basic crop growth factors, while protecting or increasing soil productivity. Compaction, decreased organic matter content, and erosion are important long-term threats to soil productivity.  相似文献   
10.
There is a growing body of literature showing that physical activity and nature have a positive effect on people's health and well-being. Additionally literature indicates that there may even be a synergic benefit from being physically active whilst simultaneously being directly exposed to nature. This insight is used in recovery programmes for work related stress and mental health care settings. However, as primary care is usually people's first point of contact with the health care system, the greatest benefits for people's health can probably be obtained in primary health care settings. The aim of the present study is therefore to investigate to what extent general practitioners advise patients on physical activity and whether they refer to the additional health benefits of physical activity in a natural environment.

A secondary analysis was performed on a random sample of 2784 video-taped patient consultations of 100 general practitioners in The Netherlands. Many characteristics of these consultations were known on the basis of earlier analyses: diagnosis, age and sex of patient and whether or not the issue of physical activity had been brought up by either patient or doctor. First, we investigated to what extent and with which health problems advice was given concerning physical activity. Second, from these consultations, a stratified sample of 100 consultations was observed in order to investigate whether an advice was given by the general practitioner concerning the additional benefits of nature. In 26% of all consultations advice on physical activity was given by the general practitioner. Physical activity was mentioned more often in cases of vague complaints than in cases with a clear cut diagnosis. As could have been expected, physical activity was mentioned relatively frequently in cases of musculoskeletal complaints and complaints of the nervous system. The additional benefits of physical activity in natural environments was not mentioned during any of the consultations.

In conclusion, general practitioners regularly give advice on physical activity. However, they fail to mention that physical activity in nature areas might have additional health benefits. Given the fact that medical treatment is increasingly evidence based, we think the evidence for the health benefits of physical activity in nature needs to be stronger. Results from such research could eventually find their way into the guidelines of the general practitioners.  相似文献   

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