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51.
为了解河南及周边地区猪圆环病毒2型(PCV2)的分子流行病学情况,运用PCR方法对2014—2015年采集到的河南及周边地区山东、山西、河北、甘肃5省共158份病料进行PCV2检测,将PCR扩增得到的PCV2 ORF2基因片段进行测序,分析研究PCV2遗传变异情况。结果显示,158份样品中,有69份样品为PCV2阳性,得到19株病毒的ORF2基因序列;将检测到的PCV2 ORF2序列与国内外分离株进行比对发现,核苷酸序列的同源性为89.9%~99.9%,其氨基酸序列同源性为88.0%~99.6%。综上可知,河南及周边地区PCV2流行广泛,病毒变异频繁。 相似文献
52.
《Veterinary Clinics of North America: Exotic Animal Practice》2017,20(3):997-1010
Abstracts should be clear, transparent, and sufficiently detailed to convey the main elements of the study, including the question, primary outcome measure, study design, and main conclusions.6 Abstracts may influence whether busy clinicians will read the full article, and, if a study is not open access, practitioners may need to make clinical decisions from abstracts only. Consider also that, with new technologies and means of accessing information, the abstract content alone may serve as the 相似文献
Methods
The Methods section provides a detailed report of the what and the how of the described research process. However, in order to maximize reader comprehension and to permit repeatability of research, several methodological aspects need to be transparently reported (Table 2). Again, by clearly defining the type of study design, investigators can then refer to the appropriate reporting guideline and supporting materials for guidance. Even where aspects of trial design may have been suboptimal, useBlinding
In research, there is often the need to blind (ie, to make people unaware) investigators (personnel and outcome assessors) and/or participants for several reasons (Table 4). When reporting any type of study, it should be made clear to readers which individuals were blinded, and to what. The use of terminology such as single, double, and triple blinding should be avoided because such terms can be variably interpreted and fail to explicitly explain blinding procedures.29 The following categoriesParticipant Flow
It is highly recommended in all study designs to depict the flow of participants with a flow diagram (Fig. 1).6, 8 Information required to complete a flow diagram for a RCT, for example, includes the number of participants evaluated for potential enrollment into the trial and the number excluded at this stage because they either did not meet the inclusion criteria or declined to participate. For each intervention group it also requires the numbers of participants which were randomly assigned,Discussion
The discussion reports the results of the study in the context of existing evidence.6, 8, 9 The investigators should cautiously interpret the results considering the objectives, limitations, multiplicity of analyses, results from similar studies, and other relevant evidence. In brief, the investigators should (1) summarize the results considering the study objectives; (2) discuss the limitations of the study, addressing sources of potential bias (both direction and magnitude), imprecision, andSummary
This article discusses aspects of research reporting. Other than purely literary reporting, there is a multitude of other types of reporting deficiencies that increase research waste (Box 1). Awareness of such problems is the first step toward improvement.53.
54.
Retrospective evaluation of 155 adult equids and 21 foals with tetanus in Western,Northern, and Central Europe (2000–2014). Part 1: Description of history and clinical evolution 下载免费PDF全文
Gaby van Galen DVM PhD DECEIM DECVECC Claude Saegerman DVM PhD DECVPH Joke Rijckaert DVM Helene Amory DVM PhD DECEIM Lara Armengou DVM PhD DECEIM Barbora Bezdekova DVM PhD DECEIM Inge Durie DVM DECEIM Rikke Findshøj Delany DVM Nathalie Fouché DVM DVM Laura Haley MVB Michael Hewetson BVSc DECEIM Rene van den Hoven DVM PhD DECEIM Anna Kendall DVM DECEIM Fernando Malalana DVM DECEIM MRCVS Jessika Muller Cavalleri DVM DECEIM PhD Tresemiek Picavet DVM DECEIM PhD Katja Roscher DVM DECEIM Denis Verwilghen DVM PhD DECVS Meret Wehrli Eser DVM DECEIM Cornélie Westermann DVM PhD DECEIM Tim Mair BVSc PhD DECEIM 《Journal of Veterinary Emergency and Critical Care》2017,27(6):684-696
55.
H. Mochizuki A. Motsinger‐Reif C. Bettini S. Moroff M. Breen 《Veterinary and comparative oncology》2017,15(3):829-839
The aim of this study was to evaluate the relationship between breed and the histopathological grade of canine mast cell tumours (MCTs). A retrospective survey of pathology data of 9375 histopathologically confirmed diagnoses of cutaneous MCTs in the US was evaluated in the context of breed prevalence in over two million registered purebred dogs. Association of histopathological grade with breed, age, sex and spay/neuter status was assessed. The data indicate that the proportion of high‐grade tumours increases with advancing age, and that male and intact dogs have increased odds of developing high‐grade tumours. A significant difference in the proportion of high‐grade tumours between breeds was detected. The Pug was at significantly increased risk of developing low/intermediate‐grade tumours, but not high‐grade tumours, resulting in preponderance of less aggressive MCTs in this breed. The results of this study suggest a genetic association for the development of high‐grade MCTs. 相似文献
56.
运用多重实时PCR对多地的养殖和野生蛙类携带虹彩病毒的本底展开调查,并进行病毒分型。结果表明,检测的样品平均阳性率为8.90%,养殖蛙的平均阳性率为4.57%,野生蛙的平均阳性率为16.82%。从蛙种类来看,养殖牛蛙和黑斑蛙带毒率较低,而养殖的棘胸蛙和野外捕捉的斑腿树蛙带毒率较高。不同蛙携带的蛙病毒的分子序列比较结果显示,不同来源的蛙病毒高度保守,缺乏明显的宿主与地域特异性,表明人工繁育场暴发虹彩病毒可能对其他野生蛙类资源产生了负面影响,建议在野生动物人工驯养繁殖体系中引入病害监测和疫病防控措施。 相似文献
57.
牛病毒性腹泻病毒(bovine viral diarrhea virus,BVDV)是导致牛腹泻的重要致病病毒之一,BVDV感染不仅能造成严重的临床症状,且可导致患畜的免疫力降低从而感染其他病原,致使患病动物的发病率和死亡率大大增加,给养牛业造成重大的损失。随着近年来分子生物学相关理论及技术不断发展,对于BVDV的研究逐渐深入,人们对该病毒的分子生物学方面有了一些新的了解,作者主要从BVDV的病毒粒子结构组成及功能、国内外的流行情况和BVDV基因的遗传与变异情况3个方面阐述近几年BVDV的分子生物学研究进展。 相似文献
58.
[目的]全面了解广西猪伪狂犬病毒(PRV)的流行特点,为相关部门制定科学的猪伪狂犬病防控措施提供决策参考.[方法]于2013年6月~2016年8月从广西12个地市不同规模猪场采集疑似猪伪狂犬病阳性组织样品473份和血清样品5041份,通过PCR和ELISA分别对组织样品和血清样品进行PRV病原和野毒抗体检测.[结果]广西地区规模猪场的组织样品和血清样品PRV阳性率分别为26.43%和24.50%,且组织样品PRV病原阳性率与血清样品野毒抗体阳性率基本一致,以2015年的PRV阳性率最低、2016年的PRV阳性率最高.在广西地区一年四季均能检测到PRV,且组织样品的PRV病原阳性率和血清样品的野毒抗体阳性率均以第三季度(秋季)最低,分别为19.80%和14.95%.除了梧州市和防城港市的检测样品未检出PRV外,其他10个地市的检测样品均能检出PRV,说明广西规模猪场普遍存在PRV感染,且以南宁、玉林、北海和桂林等地市较严重.[结论]广西规模猪场普遍存在PRV感染,尤其是2016年PRV阳性率明显上升.因此,要求养猪业发达的地市应加大对PRV的防控力度,实时监控PRV的流行趋势,避免混合感染,并做好净化工作. 相似文献
59.
为探求2012-2013年猪流行性腹泻病毒(PEDV)在福建省的流行情况,本研究采用RT-PCR方法对采自福建省125个规模猪场的257份发生腹泻病料进行PED病原检测,并分析PEDV致猪群的发病情况。结果:被检病料PEDV的阳性率为63.04%(162/257),能导致不同阶段猪群发病,尤其是对哺乳仔猪的发病率最严重,死亡率高达100%。表明:PEDV在我省发病仍较为严重,应加强防控,以减少损失。 相似文献
60.