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981.
为了快速检测鱼类神经坏死病毒,本研究设计了病毒特异性的发夹型探针,经硫醇修饰后与纳米银溶胶结合,制备了鱼类神经坏死病毒纳米探针(Ag-NNV),并使用透射电镜、多功能酶标仪、表面增强拉曼光谱仪等对纳米探针Ag-NNV的表征及发夹型探针在纳米银粒子表面的覆盖率进行了测定和分析。结果表明,裸露的纳米银粒子为球形,平均直径50 nm;制备的纳米探针颗粒为球形,平均直径90 nm。纳米银粒子和纳米探针在溶液中均具有良好的分散性。平均每个纳米银粒子表面结合发夹型探针约100条,单位表面积的探针覆盖量为0.56 pmol/cm2。该纳米探针制备简便,适合用于表面增强拉曼散射法对鱼类神经坏死病毒进行快速检测。  相似文献   
982.
结合畜牧兽医执法工作实践,总结了10项执法工作中经常遇到的问题,并有针对性的提出了处理建议,以便为国内畜牧兽医执法人员正确执法办案提供参考。  相似文献   
983.
德国畜牧业发达,在保障本国,甚至欧盟的畜禽产品供应上发挥了重要作用。本文介绍了德国畜禽产业发展的基本情况,总结了德国在畜禽屠宰管理方面的基本原则和成功做法,以期对我国畜禽产业发展和屠宰管理提供参考和借鉴。  相似文献   
984.
完善有效的法规体系,是美、欧、澳根除牛结核病等动物疫病的基础保障。其要点主要包括:健全法律制度,强化财政支持,减少利益方抵触行为;规范检测方法,对屠宰牛进行全部检疫;对阳性牛实施严格追溯制度,并分类实施标识制度;建立病牛扑杀的基本标准,选择性采取扑杀措施;推行区域化管理制度,建立差异性市场准入标准;实施野生动物隔离及监测制度,防止野生动物向家养动物传播疫情;强化利益方的宣传教育,营建群防群控氛围。这些策略和措施,对我国健全结核病防治策略具有一定借鉴意义。  相似文献   
985.
城市生活垃圾产业化处理是解决城市生活垃圾处理问题的有效途径。通过对威海市城市生活垃圾源头分类、终端处理、资源再生等进行分析,指出威海市目前存在垃圾源头分类未成体系,产业化程度低等问题。借鉴美国、德国及中国江苏省等国内外城市生活垃圾处理经验,提出建立完善的垃圾分类回收体系,提高垃圾处理产业化规模等建议,以促进威海市城市生活垃圾的产业化处理进程。  相似文献   
986.
随着养牛业的不断发展,疾病因素成为制约健康养殖的重要因素,尤其是免疫抑制性疾病的影响更不容忽视。本文针对牛免疫抑制性疾病的免疫抑制的产生机理和发生原因进行了综述,并提出了提高牛体抵抗力的方法,以期对养牛业的健康发展有所裨益。  相似文献   
987.
This study was designed not only to measure the effect of delipation on the developmental viability of pig parthenogenetically activated (PA) embryos, but also to evaluate the changes of mitochondria DNA (mtDNA), reactive oxygen species (ROS) level, adenosine triphosphate (ATP) content and gene (Acsl3, Acadsb, Acaa2, Glut1) expression level at different stages after delipation. Results showed that no effect was observed on the cleavage ability, but significant lower blastocyst rate was obtained in delipated embryos. Copy number of mtDNA decreased gradually from MII to four‐cell stages and subsequently kept consistent with blastocyst stage both in delipated and control embryos, but the copy number of mtDNA in delipated embryos was similar to that in the control groups no matter at which developmental stage was observed. Both in delipated and control embryos, ATP content progressive decreased from one‐cell to blastocyst stages, while just at one‐cell stage, a significant decrease of ATP level was observed in delipated embryos compared with that of control. The level of ROS increased obviously after delipation at cleavage stage, but no difference was seen at blastocyst stage. Finally, the expression level of genes related to fatty acids beta‐oxidation (Acadsb and Acaa2) was decreased, while the expression level of genes related to glucose metabolism (Glut 1) was upregulated after delipation. In conclusion, the reduction of lipids in pig oocytes will affect the developmental competence of pig PA embryos by disturbed energy metabolism and ROS stress.  相似文献   
988.
为了研究江苏大丰麋鹿国家级自然保护区互花米草生境中繁殖鸟巢的被捕食情况及影响捕食的因素,2014年3~6月,在保护区第三核心区鸟类繁殖生境中,使用人工巢及真实鹌鹑蛋进行巢捕食实验的方法进行巢捕食实验,分析不同巢高度、覆盖度、边缘距离、植被密度等因素对鸟巢被捕食的影响。实验共放置520个人工巢,1 040枚卵,使用红外相机对部分人工巢进行监测。结果表明:在江苏大丰麋鹿自然保护区互花米草生境内,人工巢存在较高的被捕食率,共有352巢被捕食,占67.7%,对11个变量进行逻辑斯蒂回归,巢高度、植被均高、主要植被密度、距边缘距离、水平覆盖度、上层垂直覆盖度等6个变量进人最终模型,巢高度、距边缘距离与巢被捕食显著相关。通过红外相机拍摄从102个监测巢中记录到69个捕食事件,68巢黑线姬鼠(Apodemus agrarius)和1巢黑眉锦蛇(Elaphe taeniura)捕食。我们认为互花米草生境中缺乏啮齿类动物的天敌是当地人工巢被捕食的主要原因。  相似文献   
989.
Background: Acclimatization to winter conditions is an essential prerequisite for survival of small passerines of the northern temperate zone. In the present study, we measured diurnal variations in body mass, body temperature and basal metabolic rate(BMR) for seasonally acclimatized Hwameis(Garrulax canorus).Methods: Body mass was determined with a Sartorius balance. Metabolic rates of Hwameis were measured with an open-circuit respirometry system.Results: Body masses varied with time of day and were higher in daytime for Hwameis in both summer and winter, and body masses in winter were higher compared to that in summer. Body temperatures of Hwameis were higher in daytime, and the summer acclimatized birds had significantly higher body temperatures compared to the winter acclimatized birds. BMRs of Hwameis were significantly higher during the daytime compared to the nighttime of the daily cycle in both summer and winter, and Hwameis in winter had significantly higher BMRs than that in summer.Conclusions: This result showed that Hwameis rely mostly on metabolic capacity to maintain their body temperature in cold weathers, and Hwameis exhibited daily and seasonal flexibility in morphology and physiology which is important under changing environmental conditions.  相似文献   
990.
ABSTRACT The mechanism of the effects of flumorph (a novel fungicide) was investigated by analyzing alterations of hyphal morphology, cell wall deposition patterns, F-actin organization, and other organelles in Phytophthora melonis. Calcofluor white staining suggested that flumorph did not inhibit the synthesis of cell wall materials, but disturbed the polar deposition of newly synthesized cell wall materials during cystospore germination and hyphal growth. After exposure to flumorph, zoospores were able to switch into cystospores accompanied with the formation of a cell wall, whereas cystospores failed to induce the isotropic-polar switch and did not produce germ tubes but continued the isotropic growth phase. In flumorph-treated hyphae, the most characteristic change was the development of periodic swelling ("beaded" morphology) and the disruption of tip growth. Newly synthesized cell wall materials were deposited uniformly throughout the diffuse expanded region of hyphae, in contrast to their normal polarized patterns of deposition. These alterations were the result of F-actin disruption, identified with the fluorescein isothiocynate (FITC)-phalloidin staining. The disruption of F-actin also was accompanied by disorganized organelles: each swelling of subapical hyphae was associated with a nucleus. Vesicles did not undergo polarized secretion to the apical hyphae, but diffused around nuclei for the subapical growth; thus, the cell wall was thickened with periodic expansion along the hyphae. Upon removing flumorph, normal tip growth and organized F-actin were observed again. These data, as well as data published earlier, suggest that flumorph may be involved in the impairment of cell polar growth through directly or indirectly disrupting the organization of F-actin. The primary site of action by flumorph in the disruption of the F-actin organization is under investigation.  相似文献   
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