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991.
AIM: To study the effect of hsa-miR-218 on cervical cancer HeLa cell growth and the underlying molecular mechanism.METHODS: The lentivirus expression vector pmiR-218 targeting to hsa-miR-218 was constructed. pmiR-218 was transfected into HeLa cells. The number of viable HeLa cells was counted by the method of Trypan blue exclusion. The inhibitory rate of cell activity was detected by WST-8 assay. The expression of LIM and SH3 protein 1(LASP1) at mRNA and protein levels was determined by real-time PCR and Western blot. The interaction between miR-218 and LASP1 was examined using a luciferase reporter assay.RESULTS: The lentivirus expression vector pmiR-218 targeting to hsa-miR-218 was constructed successfully and confirmed by DNA sequencing. Over-expression of miR-218 inhibited the activity of HeLa cells with the inhibitory rates of 15%, 26% and 65% at 24 h, 48 h and 72 h, respectively. The difference between transfection group and blank control/negative control group was statistically significant. The luciferase activity was reduced when co-transfection with miR-218 mimics and LASP1-3,UTR plasmid. The relative expression of miR-218 was increased after transfection with pmiR-218. Over-expression of miR-218 down-regulated the LASP1 expression at mRNA and protein levels by 25% and 75% respectively. Compared with blank control group and negative control group, the difference was statistically significant(P<0.05).CONCLUSION: pmiR-218 effectively inhibits the growth of HeLa cells in a time-dependent manner. miR-218 targets to the 3,UTR of LASP1, thus down-regulating the expression of LASP1 in HeLa cells. 相似文献
992.
CHANG Cheng JIN Peng ZHENG Wei KANG Hua-li DENG Meng-yang LI Shuang-fei WU Xiao-jing 《园艺学报》2015,31(1):12-17
AIM: To study the expression of Jagged2/Notch3 signaling molecules in pulmonary vascular wall of pulmonary hypertensive rats induced by monocrotaline. METHODS: SD rats were randomly divided into normal control group (C group,n=15), solvent control group (S group,n=15) and monocrotaline model groups (M group,n=15). The model of pulmonary hypertension was established by a single subcutaneous injection of monocrotaline (50 mg/kg). The rats in S group were given a single subcutaneous injection of the same dose of solvent. After 4 weeks, the pulmonary vascular remodeling was assessed by HE staining, and the mean pulmonary artery pressure (mPAP) and right ventricular systolic pressure (RVSP) were determined by right heart catheterization. The expression of Jagged2/Notch3/Hes5 molecules in the pulmonary vascular wall was detected by immunohistochemical method and real-time PCR. RESULTS: Compared with S group and C group, the percentage of medial wall thickness of smaller arteries in model group increased significantly (P<0.01). The levels of mPAP and RVSP in M group were significantly higher than those in S group and C groups (P<0.01). The results of real-time PCR showed that the expression of Jagged2, Notch3 and Hes5 was significantly increased in M group compared with S group and C group. The data from immunohistochemical detection indicated that Jagged2 mainly expressed in the intima of small lung artery, Notch3 and Hes5 mainly expressed in the medial smooth muscle cells. Compared with S group and C group, the expression of Jagged2 and Notch3 was significantly increased in the lung small arteries of M group. CONCLUSION: The activation of Jagged2/Notch3 signaling pathway might play an important role in the formation of pulmonary hypertension. 相似文献
993.
Most potato transgenic research has focused on development of resistance to pathogens and modification of potato physiology.
Many transgenes, particularly those conferring pathogen resistance, could substantially lower potato production costs in developing
countries. However, transgenes have not been reported in sexually propagated 4x-2x potato hybrids commonly grown in developing countries. Two transgenes,the Bacillus thuringiensis cry3Aa endotoxin protein gene and the PVY°coat protein gene, were engineered intodiploid and tetraploid potato using Agrobacterium tumefaciens-mediated transformation. Cry3Aa was produced at high levels in several lines while the PVY° coat protein was not expressed.
Diplandroid and tetraploid genotypes were crossed to produce transgenic 4x-2x hybrids. Genetic transformation had no discernable effect on fertility ofthe primary transformants, germination of4x-2x seed derived from the transformants and agronomic performance(tuber set, average tuber weight and total tuber yield) of the
4x-2xhybrids. The transgenic 4x-2xhybrids produced non-viable pollen and could only be crossed as female parents. Results suggest that transgenes, such ascry3Aa, could be expressed in 4x-2x hybrids to lower costs of production with no significant effect on plant phenotype.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
994.
利迪链霉菌A02诱导番茄抗灰霉病作用机制研究——对植株防御酶系的影响 总被引:3,自引:0,他引:3
利用利迪链霉菌生防菌株A02发酵液和番茄灰霉病菌对番茄植株进行诱导和接种处理,利用分光光度法测定处理前和处理后1~5 d番茄叶片组织的主要防御酶系——苯丙氨酸解氨酶、过氧化物酶、过氧化氢酶和多酚氧化酶的活性变化。试验结果显示,不接种灰霉病菌而单独诱导处理、接种灰霉病菌后诱导处理和诱导处理后接种灰霉病菌这3种处理都能提高番茄植株各防御酶系的活性,后者酶活性峰值最高,对番茄植株灰霉病的抑制作用也最明显,控制效果达94.92%。 相似文献
995.
996.
Virtual studio system (VSS), a new technology based on virtual reality, develops fast in recent years. Virtual studio concept replaces real background sets with computer generated 3D synthetic and combines real foreground action, with computer generated backgrounds. As VSS need not construct real background sets and has little limitness of time and space, it is regarded as a revolution in TV programs. This paper mainly discusses about the background, technology feature, application and future. 相似文献
997.
通过对天祝白牦牛高硫角蛋白基因启动子B2A克隆得到其序列,将序列提交到NCBI,登录号:KJ910005,并对其进行生物信息学分析,通过亚细胞定位,磷酸化分析,二级、三级结构和保守结构域预测结果比较,MEGA 5.10软件进行NJ法进化树构建和Meg Align进行蛋白质相似分析来分析B2A基因与KAP1.1(Keratin associated protein1.1)基因的差异性。B2A基因的CDS区全长为471 bp,共编码156个氨基酸,二级结构含有延伸链、β转角和无规卷曲3种。B2A蛋白和KAP1.1蛋白的亚细胞定位,磷酸化分析,保守结构域,二级结构、三级结构和同源性差异较大。但是从功能预测结果显示2个蛋白功能完全一致,并且使用Clustal X进行氨基酸序列比对分析显示B2A蛋白从第33位开始相对于KA1.1蛋白有10个氨基酸的缺失以外,其余序列之间的保守性相当高。因此,可以证明B2A基因是KAP1.1基因的基因亚型。 相似文献
998.
观察小鼠ES-D3细胞在MEF、新生牛睾丸支持细胞(nBTSCs)和新生兔睾丸支持细胞(nRTSCs)饲养层上生长4 d nanog基因的表达水平和生长行为。RT-PCR分析显示,MEF饲养层上培养4d的ES-D3 nanog基因含量高;nBTSC饲养层上培养nanog基因表达较低;而RTSC饲养层上培养nanog基因表达最低。结果显示:不同饲养层上的ES-D3细胞集落形态和培养4d分化程度有差异。在MEF饲养层上的ES-D3细胞培养4d,集落形态仍然很规则,细胞间紧密,集落表面少见大细胞,AKP染色强阳性。在nBTSC饲养层上的ES-D3细胞,集落界限清晰,AKP染色显示,集落大部分细胞呈阳性,少数的细胞集落为弱阳性,可见集落表面分散有较多的大细胞。在nRTSC饲养层上的饲养层上的ES-D3,集落隆起不明显,集落界限不清晰,大部分集落形态不太规则,AKP染色显示集落中部分细胞呈阳性,少数的细胞集落为全阴性,集落表面有较少的大细胞,集落周围有伸出的成纤维细胞。 相似文献
999.
1000.
玉米改良单交种选育方法的研究:Ⅱ.姊妹系和姊妹种的配合力研究 总被引:3,自引:0,他引:3
以GrifingII双列杂交试验和NCII遗传交配试验,测定玉米8个姊妹系及其28个姊妹种的一般配合惫,结果两者基本一致。玉米妹系的一般配合力是一种遗传特性,它既可遗传给其组成的姊妹种,又能通过姊妹和种遗传给其组成的改良单交种;姊妹种的一般配合力与其双亲姊妹系一般配合力均值之间没有显著差异,并呈密切相关,这阐明了改良单交种与其对应的普通单交种相似的原因,并为改进和简化改良单交种选育程序提供理论依据 相似文献