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81.
内蒙古阿拉善荒漠啮齿动物群落结构及其多样性研究   总被引:6,自引:0,他引:6  
武晓东  阿娟  付和平 《草地学报》2003,11(4):312-316
对内蒙古阿拉善荒漠区啮齿动物群落结构和多样性进行了研究。依据样地种多度(捕获率)聚类方法,并结合生境中地带性植被类型的综合特征,该荒漠区啮齿动物可划分为6个地带性群落。Ⅰ.小毛足鼠(Phodopus roborovskii)+三趾跳鼠(Dipus sagitta)+子午沙鼠(Meriones meridianus)群落。Ⅱ.长尾仓鼠(Cricetulus longicaudatus)+大林姬鼠(Apodemus speciosus)群落。Ⅲ.五趾跳鼠(Allactaga sibirica)+子午沙鼠(Meriones meridianus)+三趾跳鼠(Dipus sagitta)群落。Ⅳ.三趾跳鼠(Dipus sagitta)+小毛足鼠(Phodopus roborovskii)+子午沙鼠(Meriones meridianus)群落。Ⅴ.长耳跳鼠(Euchoreutes naso)+五趾跳鼠(Allactaga sibirica)群落。Ⅵ.子午沙鼠(Meriones meridianus)+黑线仓鼠(Cricetulus barabensis)群落。其中群落Ⅲ多样性指数最高,为2.0557;群落I与群落IV的相似性系数最大,为0.5147;群落Ⅲ具有代表性。该荒漠区啮齿类数量与生境中的土壤水分、土壤基质呈显著正相关;与建群植物种数呈显著负相关;而与生境的海拔高度相关性极低。  相似文献   
82.
Zokors are common subterranean rodents that inhabit agricultural fields, shrublands, and grasslands in the arid and semi-arid regions of China. Zokor burrowing activities can alter soil structure and affect soil hydrological processes; however, there are few studies regarding their effects on soil preferential flow in the Mu Us sandy land. An evaluation of the effects of zokor disturbance on their habitat and soil water is important for understanding the ecological role of zokors in the soil eco...  相似文献   
83.
林区啮齿动物群落管理中的生态阈值研究   总被引:9,自引:5,他引:4  
以人工林生态系统中的啮齿动物群落和主要造林树种为研究对象,提出了人工林群落生态阈值概念.采用系统分析法,组建了刺槐、油松、侧柏被害模型和飞播造林30 d种子损失模型,并以国家及地方标准的最大允许损失指标偶联求得林区啮齿动物群落管理中的生态阈值模型.结果表明,群落总密度和地面鼠的单因子群落生态阈值刺槐最大,油松次之,侧柏最小;鼢鼠和田鼠在高允许损失率下为刺槐>油松>侧柏,而在低允许损失率下为油松>侧柏>刺槐;草兔为油松最大,侧柏最小;飞播造林中的单因子群落生态阈值不仅决定于地面鼠的总密度,而且还决定于群落各  相似文献   
84.
刘晓光  陈文君 《安徽农业科学》2011,39(20):12184-12185,12252
从黑龙江省的实际情况出发,根据1996~2009年的统计数据,对森林病虫鼠害、火灾以及其他森林灾害进行了分析,运用层次分析法以及德尔菲法构建了黑龙江省森林灾害安全警示指标体系以及森林灾害安全预警指数,并划分了安全警度等级,进而对黑龙江省森林灾害的程度进行了探讨。  相似文献   
85.
Fertility control is an alternative strategy to traditional culling for the management of rodent pests. Previous studies have demonstrated that quinestrol is a potential contraceptive for male rodents, but the recovery of fertility in quinestrol‐treated rodents has not been evaluated. This study used C57BL/6J mice to evaluate the recovery rate of male fertility after the administration of quinestrol. Diethylstilbestrol (DES), a non‐steroid estrogenic compound, was used for comparison. Different groups of mice were treated with 1 mg/kg quinestrol, 1 mg/kg DES, or castor oil separately for 7 days. These mice were then killed on days 8, 22 and 50 respectively. Our results indicated that the weight of epididymides and seminal vesicles decreased significantly on days 8 and 22 in quinestrol/DES‐treated mice, with extensive histological changes in the seminiferous tubules. Sperm concentrations in the cauda epididymal fluid were significantly reduced on days 8 and 22 in both quinestrol and DES treatment groups and on day 50 for the DES, but not the quinestrol group. Further analysis revealed that DES‐treated mice exhibited a higher proportion of abnormal sperm accumulation in the epididymis, indicating that the normal sperm transportation to the cauda epididymis was blocked. Our results indicate that the anti‐fertility effects on male mice given quinestrol were of shorter duration than for those receiving DES at the dose of 1 mg/kg body weight.  相似文献   
86.
Salmonella Enteritidis in contaminated eggs is a public health hazard that may cause hospitalization or death in the elderly, infants, and individuals with impaired immune systems. Prevention of Salmonella Enteritidis infection of laying hens is an essential first step in reducing Salmonella Enteritidis outbreaks in humans. Multiple interventions at several stages during egg production can combine to reduce numbers of infected chickens and keep egg contamination to low levels. Every effort should be made to exclude Salmonella Enteritidis from egg production premises by implementing effective biosecurity measures, stocking the farm with Salmonella Enteritidis-free replacement pullets, controlling rodent and insect vectors, and denying wild birds and pets access to chicken houses. Diligent cleaning and disinfection of chicken houses before introduction of a new flock will minimize environmental exposure and indirect horizontal transmission of multiple pathogens, including Salmonella Enteritidis. Increased resistance of chickens to intestinal colonization by Salmonella Enteritidis can be attained by the use of probiotics, prebiotics, and synbiotics. Laying hens should be immunized with live and killed vaccines to stimulate mucosal and systemic immunity and reduce the prevalence of Salmonella Enteritidis-contaminated eggs. Shell eggs should be refrigerated as soon as possible after laying to keep Salmonella Enteritidis cells at low levels in any contaminated eggs. Comprehensive Salmonella Enteritidis-control programs have proven to be successful in reducing the incidence of Salmonella Enteritidis infections in both egg-laying flocks and humans.  相似文献   
87.
运用灰色系统理论和拓扑预测法建立灰色模型对新疆玛纳斯县小家鼠秋季数量动态进行预测,预测精度较高。表明该方法在种群动态预测中具有较高应用价值。  相似文献   
88.
Rodents are reservoirs of various types of hantavirus, some of which are agents of hantavirus pulmonary syndrome in humans. Each hantavirus is associated with a single rodent host species but successive spill‐over events may eventually lead to host‐switching and new species’ becoming host of a given pathogen. This study aims to gain an understanding of the spatial ecology of two hantavirus‐host species, Akodon azarae, and Oligoryzomys flavescens, by identifying factors modulating their home range sizes and stability, and by evaluating intra‐ and interspecific spatial aggregation for these species and a third one—Oxymycterus rufus—living in sympatry. For this, eleven capture‐mark‐recapture surveys were carried out, spanning 22 months. We found that A. azarae males have larger and more mobile home ranges than females, independently of the season. Consequently, males could likely have a more relevant role in the transmission of hantavirus because of their greater exposure both to a higher number of contacts between individuals and viral contamination of the environment. Contrasting, O. flavescens individuals showed negligible displacements of their home range through time, which could limit the range of hantavirus spread in host populations. Since O. flavescens is host to Lechiguanas hantavirus (pathogenic to humans) this result encompasses epidemiological relevance, for it may imply the existence of local foci of infection. Additionally, individuals of both species performed excursions outside their home ranges. These events could enable hantavirus spread over distances beyond the normal range of movements and lead to new hantavirus outbreaks in formerly non‐infected rodent populations, favoring the persistence of the virus in nature.  相似文献   
89.
We tested FSHp, eCG and FSHp + eCG to establish ovum pick-up (OPU) and in vitro maturation method in spotted paca. Eight healthy adult females were subjected to each of four treatments to stimulate ovarian follicular growth. All females were subjected to a hormonal protocol using a single dose of 45 mg of injectable progesterone and single intramuscular injection of 0.075 mg d-cloprostenol on day 6. Ovarian stimulation was carried out as follows: in Group TFE (FSHp and eCG), animals were treated with a single dose of 80 mg of FSHp and 200 IU of eCG intramuscularly on day 6 after the application of progesterone; in Group TF (FSHp), they were treated with a single dose of 80 mg of FSHp intramuscularly on day 6 after application of progesterone; in Group treatment eCG, they were treated with 200 IU of eCG intramuscularly on day 6 after application of progesterone; and in Group TC (saline solution), 1 ml of saline solution was administered to control does. The OPU was performed between 22 and 26 hr after gonadotropin treatments. All recovered oocytes were placed into maturation media and incubated for 24 hr. There were no differences among the mean number of observed follicles, aspirated follicles and oocytes recovered per treatment. Oocyte maturation rates did not differ among groups, except, TF and treatment eCG oocytes had greater maturation rates than TC oocytes. In this study, gonadotropin administration failed to superovulate treated does and increase oocyte retrieval efficiency. Despite the feasibility of the procedure, further studies are needed to develop and refine hormonal protocols for oocyte recovery and in vitro maturation in this species.  相似文献   
90.
内蒙古阿拉善荒漠啮齿动物群落格局的干扰效应   总被引:1,自引:0,他引:1  
2002年~2004年在阿拉善荒漠区的典型地区选择了4种不同干扰条件的样区:开垦区、轮牧区、过牧区和禁牧区。4种不同干扰条件下啮齿动物群落格局的调查采用铗日法,在每个干扰区布设4个样地,每个样地面积10hm^2,每个样地布放500铗日,每个干扰区共布放2000铗日。取样时间为每年的4月、7月、10月。以不同月份下各干扰区各布铗样地啮齿动物群落的鼠种组成比例建立数据矩阵,应用SAS8.1软件的对应分析程序对其进行分析,得出不同月份各干扰区各布夹样方啮齿动物群落在前两个主因子轴上排列的二维散点图。结果表明,开垦区和禁牧区的群落格局相似,黑线仓鼠和子午沙鼠与开垦区和禁牧区有着较稳定的对应关系;小毛足鼠与轮牧区有着较稳定的对应关系;三趾跳鼠和三趾心颅跳鼠与过牧区的对应关系较稳定。  相似文献   
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