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1.
We developed an H5/H7 trivalent inactivated vaccine by using Re-11, Re-12, and H7-Re2 vaccine seed viruses, which were generated by reverse genetics and derived their HA genes from A/duck/Guizhou/S4184/2017(H5 N6)(DK/GZ/S4184/17)(a clade 2.3.4.4 d virus), A/chicken/Liaoning/SD007/2017(H5 N1)(CK/LN/SD007/17)(a clade 2.3.2.1 d virus), and A/chicken/Guangxi/SD098/2017(H7 N9)(CK/GX/SD098/17), respectively. The protective efficacy of this novel vaccine and that of the recently used H5/H7 bivalent inactivated vaccine against different H5 and H7 N9 viruses was evaluated in chickens. We found that the H5/H7 bivalent vaccine provided solid protection against the H7 N9 virus CK/GX/SD098/17, but only 50–60% protection against different H5 viruses. In contrast, the novel H5/H7 trivalent vaccine provided complete protection against the H5 and H7 viruses tested. Our study underscores the importance of timely updating of vaccines for avian influenza control.  相似文献   
2.
将Ⅳ索12型索道应用于狭长工作面的采石场的石材搬运和装车作业。该索道系统中闽林721绞盘机的摩擦卷筒、跑车及游动滑车都进行了改装设计使其达到4倍增力起重、双向牵引,最大起重量可达9t。实践表明在特殊困难地形将林业索道用于采石场作业有明显效益。  相似文献   
3.
在MRS平板上,采用琼脂扩散法测定了Nisin对Lactobacillus acidophilus La-5和Bifidobacterium bifidum Bb-12生长的抑制作用。当Nisin浓度≥50ug/ml时,对Lactobacillus acidophilus La-5表现出强烈的抑制作用,而Bifidobacterium bifidum Bb-12则几乎不生长,即使Nisin的浓度仅为25ug/ml,当L.acidophilus La-5和B.bifidum Bb-12单独或两者共同在37℃发酵10%(w/w)还原脱脂奶时,脱脂奶中添加的50ug/ml Nisin对B.bifidum Bb-12表现出杀菌作用,而对L.acidophilus La-5则为抑菌作用。当延长培养时间后。L.acidophilus La-5的存在可以降低Nisin对B.bifidum Bb-12的致死作用。  相似文献   
4.
A new technique by High Performance Liquid Chromatography (HPLC-gel permeation) shows promise as a tool to separate and quantitate the Unsaturated Vitamin B(12) Binding Capacity (UBSC) of the individual Vitamin B(12) binders in blood serum. This method, although not as rapid as protein-coated charcoal or cellulose separation techniques, is more applicable for use with large numbers of samples than gel filtration. The use of a radioactivity detector to monitor the eluant from the column permitted automation of the method. Comparable results for UBBC and for the UBBC of individual binders were obtained when samples were analyzed by gel filtration and HPLC. The HPLC method proved suitably precise and the recovery of added cyanocobalamin was acceptable. It is proposed that HPLC be the method of choice for measurement of the USBC of binders of Vitamin B(12) in blood serum.  相似文献   
5.
用优良自交系Q12作母本,F51作父本配制的一代杂种津优12号,植株生长势中等,叶色深绿,瓜条顺直,长棒状,长35 cm左右;单瓜质量200g左右,瓜色深绿,有光泽,瘤显著,密生白刺,果肉淡绿色,质脆,味甜,畸形瓜率低;春季主蔓第1雌花着生在第4节左右,雌花节率高.春露地栽培产量可达5 500kg·(667m2)-1左右,秋大棚栽培产量4 200kg·(667 m2)-1.抗枯萎病、霜霉病、白粉病和CMV.适宜华北、东北、西北地区春露地和秋大棚栽培.  相似文献   
6.
AIM:The β-catenin is a key molecule in the Wnt signal pathway, which plays a critical role in normal development and tumorigenesis. However, the mechanisms of the β-catenin on the cell growth control are still not completely defined. The aim of this study was to test the hypothesis that the mutant β-catenin may regulate the hepatocyte proliferation. METHODS: The immortalized murine hepatocyte cell line, AML12, was used for this study. A plasmid that contain mutant β-catenin S33Y was transfected into the AML12 cells and a stable cell line AML12S33Y was established. The cell growth property of this cell line and the parental cell were compared by flow cytometry analysis and direct cell count. The cells were also tested for the ability to form soft agar colonies, and the ability to form tumors in the severe immune deficient mice (SCID). RESULTS:1. The mutant β-catenin containing cell line AML12S33Y has higher proliferating index compared with the parental AML12 cells (P<0.01), suggesting that mutant β-catenin promotes cell growth. 2. The mutant β-catenin cells formed small colonies in soft agar after 4 weeks of culture, but did not generate tumor in SCID mice. CONCLUSION:The mutant β-catenin promotes liver cell growth.  相似文献   
7.
AIM: IL-12 acts upon Tlymphocytes and activates its receptor complexes of β1/β2,and so IL-12 can regulate TH1/TH2 balance. Our study is aimed at IL-12-inducing apoptosis of Tcells and expression and signal transduction of Fas/FasLduring Tcell apoptosis. METHODS: The apoptosis of Tcells was detected by Annexin Vstaining cytometry and the expression of Fas/FasLunder different inhibitors were detected by semi-quantitative PCR. RESULTS: IL-12 induced the human leukemic Tcell line(TIB-152) and the human lymphoma Tcell line(HTB-176) and the normal human Tcells to undergo apoptosis. The FasLexpression at 6 hours after treatment with IL-12 increased apparently, and reached the max at 24 hours, and FasLexpression induced by IL-12 was inhibited by PKCinhibitor. But IL-12 did not influence Fas expression. CONCLUSIONS: IL-12 can induce Tcells to undergo apoptosis which is characterized by early membrane changes, the inducing effect is correlated with the concentration of IL-12 and the maturation of Tcells. FasLparticipates in the progression of Tcell apoptosis as a apoptosis mediator, and the effect of IL-12 on FasLexpression may be related with PKCpathway.  相似文献   
8.
AIM: In order to study the relationship between the ERK and p38 MAPK activation and the protection of 11, 12-epoxyeicosatrienoic acid (11, 12-EET) and ischemia preconditioning (IP), the effects of 11, 12-EET and ischemic preconditioning on phosphorylated ERK and p38 MAPK during ischemia and reperfusion in rat myocardium were examined. METHODS: The rat heart was subjected to ischemia for 5 min by ligating the left anterior descending coronary artery followed by reperfusion for 5 min (two times) to undergo ischemia preconditioning. The rats were divided into 5 groups: (1) control; (2) sham group; (3) ischemia/reperfusion (I/R) group, in which the rat heart suffered from 60 min ischemia followed by 30 min reperfusion; (4) IP plus I/R group; (5) EET plus I/R group, in which 6.28×10-8 mol/L 11, 12-EET was injected intravenously 20 min before I/R. The heart function was examined, and phosphorylated ERK and p38 MAPK were detected by Western blot. RESULTS: At 30 min reperfusion, +dp/dtmax, -dp/dtmax and LVDP decreased significantly in I/R group compared with sham group, IP plus I/R group and EET plus I/R group; Phosphorylated ERK1/2 level was higher in I/R group than sham group, but was lower in I/R group than IP plus I/R group and EET plus I/R group; Phosphorylated p38 MAPK level was lower in control, sham, IP plus I/R and EET plus I/R group than I/R group. CONCLUSION: 11,12-EET protects rat heart against ischemia/reperfusion injury, the mechanism may be related to activation of ERK1/2 and inhibition of p38 MAPK.  相似文献   
9.
10.
“高粱+再生高粱”高产高效栽培技术研究   总被引:2,自引:0,他引:2  
为提高高粱在"种植一季有余、两季不足"的温光资源条件下的种植效益,以‘泸糯12号’为研究材料,通过优化播期、促芽肥等关键技术研制"高粱+再生高粱"高产高效栽培技术,再与传统技术进行对比试验。结果表明,"高粱+再生高粱"高产高效栽培技术要点是2月底至3月5日前播种,种植密度101055株/hm~2,头季高粱收获前10天及时施纯氮150 kg/hm~2,留桩高度控制在近地面第1节位,每窝保留再生苗2~3苗。应用"高粱+再生高粱"高产高效栽培技术后两季高粱产量和效益,较传统高粱种植技术分别增长120.3%、84.3%,增产增效效果显著。因此,"高粱+再生高粱"高产高效栽培技术适宜区域大面积推广。  相似文献   
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