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根据GenBank中BVDV-1、BVDV-2、CSFV及新出现瘟病毒的基因序列,设计2对特异引物,建立了能鉴别诊断BVDV与CSFV的Nested-PCR检测方法;确定其方法的特异性、敏感性、稳定性。建立的Nested-PCR能从BVDV标准毒株、猪源BVDV毒株中扩增198bp特异性片段,对猪瘟病毒、猪繁殖与呼吸综合征病毒检测结果为阴性。结果表明,该方法具有较好特异性;其敏感性可检测到0.195fg RNA模板量;经重复性试验表明该方法具有良好稳定性。初步应用检测表明,猪BVDV阳性率较高,达36.0%;牛血清及其制品、猪瘟活疫苗BVDV污染严重。本试验建立的Nested-PCR具有敏感、特异和稳定等特点,可用于临床诊断和流行病学调查。 相似文献
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产肠毒素大肠埃希茵的主要黏附素抗原有K88、K99、987P和F41,在发病学和免疫学上扮演着重要的作用。文章就其理化特性、生物学特性、分子生物学特性及主要检测方法进行综述。 相似文献
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HANG Tianyu ZHAO Hongzhe SONG Qianjin ZHANG Jing JI Zhi WEN Yongjun GUAN Pingyuan 《中国畜牧兽医》2007,47(11):3641-3650
In this study,the genome of Brucella Rev.1 strain was used as a template to amplify the BAB gene sequence,clone it into the prokaryotic expression vector pET-30a(+),obtain the recombinant plasmid pET-30a-BAB,and perform prokaryotic expression on the recombinant plasmid.The indirect ELISA method was constructed by using the expression products detected by Western blotting.The results showed that the BAB gene was successfully cloned and expressed in this experiment,and the purified expression product was analyzed by SDS-PAGE.This study obtained a relatively pure recombinant BAB protein;Western blotting test showed that the expressed protein could react specifically with Brucella sheep positive serum and had good reactogenicity;Using the recombinant BAB protein as the coating antigen,an indirect ELISA method for detecting BAB antibodies was established and optimized.The best determined coating conditions were as follows BAB protein coating amount was 0.25 μg/mL,serum dilution was 1:400;blocking solution was 3% pig-derived gelatin;secondary antibody dilution was 1:6 000;color development time was 10 min.The established method was used to detect 40 clinical sheep serums,and the cut-off value was calculated to be 0.607.That was,when the serum tested had P/N ≥ 1.5 and D450 nm ≥ 0.607,it was judged as positive,when D450 nm ≤ 0.561,it was judged as negative,and when 0.607<D450 nm<0.561,it was judged as a suspect value,and retest was required.Compared with the Huhong plate test and the test tube agglutination test,the positive coincidence rate was 100%,the negative coincidence rate was 71.88%,and the total coincidence rate was 77.5%. 相似文献
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通过对家蚕 (Bombyxmori) 5龄第 5日幼虫马氏管外部形态和内部组织结构的观察 ,发现不同部位马氏管的结构差异很大 :膀胱呈囊状体开口于小肠两侧 ,肌肉层厚、细胞层较薄 ,内腔很大 ;下行管靠膀胱处圆形 ,较膨大 ,其余大部分外型呈扁平形且表面光滑 ,细胞层较薄 ,内缘有微绒毛状突起、管腔较大 ;上行管前部管体稍扁平 ,结构与下行管相似 ,中后部管体圆形、细胞层肥厚、内缘呈蜂窝状、管腔狭小 ;隐肾管的外列马氏管细胞层薄、管腔较大 ,而内列马氏管细胞层肥厚、管腔很小。马氏管结构的差异与各部位的功能有密切关系。 相似文献
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ZHANG Shengying WU Xiaochun XING Xiaoyong LIU Jia YUE Yahui ZHANG Yangyang HE Jian WEN Fengqin BAO Shijun 《中国畜牧兽医》2007,47(10):3149-3157
The aim of this study was to investigate the effect of P48 protein on proliferation and apoptosis of embryonic bovine lung (EBL) cells.In this study,samples which co-incubated with P48 protein and EBL cells in different concentrations at different time points were collected,the proliferation rate of the cells was detected by MTT method,and the changes in the nuclear morphology of EBL cells were observed by DAPI staining method.Meanwhile,flow cytometry was used to detect the apoptosis rate of EBL cells induced by P48 protein.Real-time quantitative PCR was used to detect the changes in mRNA level of apoptotic marker genes,and Western blotting tested the Bax and Beclin-1 protein expressions.The results showed that under the condition of 72 h and 10 μg/mL of protein concentration treatment,P48 extremely significantly inhibited EBL cells proliferation (P<0.01),while 0.1 and 0.5 μg/mL protein concentration had no inhibitory effect (P>0.05).The nuclear morphology showed no significant change after protein induction for 12 h,but wrinkled and condensed at 24 h.The nucleus was fragmented,and a sprouted apoptotic body was appeared at 48 and 72 h.Apoptosis related genes expression showed no obvious increase at 2 and 12 h at mRNA level,but gradually increased at 24,48 and 72 h,and it showed a time-dependent manner.Accordingly,the expression of apoptosis marker proteins Bax and Beclin-1 significantly increased.Flow cytometry analysis showed that the apoptosis rate of EBL cells induced by P48 protein was 48.44%.In conclusion,P48 recombinant protein of Mycoplasmas bovis inhibited the proliferation of EBL cells and promoted their apoptosis,which provided reference for revealing the pathogenic mechanism of Mycoplasmas bovis. 相似文献
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