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181.
2018 年,在河北省保定市园林植物紫荆(Cercis chinensis)根围分离到一种长针线虫。经形态
学观察和 28S rDNA D2D3 区序列分析,将其鉴定为松长针线虫(Longidorus pinus Xu, Ye, Wang & Zhao)。
其雌虫主要形态特征为:雌虫体长 3 048~3 464 μm,唇区明显缢缩,宽 9.5~10.5 μm,侧器囊袋状,齿尖
针长 66.0~69.5 μm,导环距体前端 27.5~30.0 μm,尾长 31~33 μm,短圆锥形,尾长与肛门处体宽比值=
1.5~1.6。松长针线虫河北种群 28S rDNA D2D3 区与 GenBank 数据库的山西种群进行序列比对,相似性为
99.2%~99.9%。松长针线虫是河北省长针线虫新纪录种。紫荆是松长针线虫的新寄主。 相似文献
182.
183.
研究了杉木(Cunninghamia laceolata)木粉不同粒度对羧甲基取代度及丙烯酸接枝高吸水树脂吸水率的影响规律。结果表明,100目和200目木粉与40目木粉X射线衍射峰没有区别,表明100目和200目木粉纤维结晶没有被破坏,木粉粒度对羧甲基取代度的影响不大;100目和200目木粉直接接枝丙烯酸聚合物吸水倍率明显降低,表明木粉颗粒逐渐变小,木粉原有的空间结构被破坏,不足以形成网络结构;红外光谱分析表明,杉木木粉羧甲基化后,纤维素和半纤维素中引进了大量的羧甲基,且保留了木质素特征峰,但在丙烯酸接枝的高吸水树脂中木质素吸收特征峰不存在,说明过硫酸钾引发剂产生的自由基优先与木质素苯环反应,使木质素苯环开裂,导致木质素苯环的吸收特征峰消失。 相似文献
184.
对枳椇果渣不溶性膳食纤维(IDF)的化学法提取工艺、双氧水脱色工艺进行了研究,并对产品的营养成分和功能性质进行分析。通过单因素及正交试验确定最佳的化学法提取工艺为:以液料比为8∶1(mL∶g)、浓度为1.5mol/L的氢氧化钠溶液,在20℃条件下处理40min后过滤,冲洗至中性,然后取滤渣转移至液料比为6∶1(mL∶g)、pH值2的硫酸溶液中,60℃下作用60min,冲洗至中性,干燥。不溶性膳食纤维的提取率为74.02%,质量分数由果渣中的62.62%(干基计)提高到84.97%;双氧水脱色的最佳工艺条件为:5%H2O2、pH值12、45℃、5h,在此条件下不溶性膳食纤维的白度由51.63%增加到60.21%;制备的膳食纤维产品的持水力由果渣中2.4g/g增加到4.3g/g、持油率由2.3mL/g增加到3.9mL/g、结合水力由2.6g/g增加到4.7g/g、膨胀力由2.8mL/g增加到4.6mL/g。 相似文献
185.
186.
187.
以欧亚种酿酒葡萄"赤霞珠"为试材,采用分光光度法,系统比较了金沙江流域和澜沧江流域不同海拔"赤霞珠"葡萄果实品质差异及其发育期品质指标的积累规律,以期为香格里拉及世界其它高海拔产区优质和特色葡萄与葡萄酒的生产提供参考。结果表明:较长的日照时长、较强的紫外辐射及较大的温差使得位于海拔2 121m的溜筒江生产的"赤霞珠"葡萄果实还原糖含量最高(265.16g·L-1),总酸最低(4.01g·L-1)。另外,位于海拔2 238m的达日生产的"赤霞珠"葡萄果实总酚、单宁和果皮总花色苷含量最高(分别为8.58mg·g-1、11.54mg·g-1和160.53A520·g-1)。金沙江和澜沧江流域各产地发育期葡萄果实可溶性固形物和还原糖含量均呈升高趋势,总酸均呈先增加后降低趋势。金沙江流域(瓦卡和达日)比澜沧江流域(西当、斯农和阿东)葡萄果实还原糖快速积累期和总酸快速下降期普遍提前2周左右。金沙江流域和澜沧江流域各产地在海拔2 000~2 250m范围内,成熟期葡萄果实中总酚、单宁和果皮总花色苷含量随着葡萄园海拔升高而升高,并均在各流域2 250m附近的葡萄园达最高。随着葡萄园海拔再度升高,到海拔最高的阿东(2 602m),其葡萄果实中总酚和单宁的含量又有所下降,但是果皮总花色苷没有显著变化。金沙江流域2个产地葡萄果实总酚和单宁含量在整个发育期内的积累规律与澜沧江流域4个产地不同,且达到最大值的时期也不同。可能是由于澜沧江流域溜筒江产地的风土条件与金沙江流域类似,其发育期内品质指标,特别是还原糖和总酸含量的变化与金沙江流域具有类似的模式。 相似文献
188.
ZHANG Yu-xuan LI Chun-wei MAO Wen-hao ZHU Ke-yan SHAO Yang-qian DENG Xiao-ming 《园艺学报》2019,35(1):8-14
AIM: To explore the target relationship between microRNA-140-3p (miR-140-3p) and programmed cell death ligand 1 (PD-L1) and their effect on the viability, migration and invasion of non-small-cell lung cancer A549 cells.METHODS: RT-qPCR was used to detect the miR-140-3p expression in HLF-1, A549 and H1299 cells, and then the A549 cells with the most significant difference were selected as the subsequent research object. TargetScan software and dual-luciferase reporter assay were performed to predict and confirm the target relationship between miR-140-3p and PD-L1. RT-qPCR and Western blot were used to determine the effects of miR-140-3p mimic and inhibitor on PD-L1 expression level. MTT assay was used to detect the viability of A549 cells. Transwell assay was performed to detect the migration and invasion abilities of the A549 cells.RESULTS: miR-140-3p was significantly down-regulated in the A549 cells and H1299 cells (P<0.05). Transfection with miR-140-3p mimic decreased the expression of PD-L1 and inhibited the viability, migration and invasion of the A549 cells. Transfection with pcDNA3.0-PD-L1 reversed the inhibitory effect of miR-140-3p on the viability, migration and invasion of the A549 cells.CONCLUSION: miR-140-3p inhibits the viability, migration and invasion of A549 cells by targeting PD-L1. 相似文献
189.
AIM: To investigate the inhibitory effect of microRNA-145 (miR-145) on epithelial-mesenchymal transition (EMT) in renal cancer A-498 cells. METHODS: The A-498 cells were transfected with miR-145 mimics (M145) and mimic negative control(MNC), which served as M145 group and MNC group, respectively. Mock control (MC) group was set up using untreated A-498 cells. The expression level of miR-145 in each group was detected by RT-qPCR. Transwell assay was used to detect the invasion ability of the cells. The protein expression of vimentin, E-cadherin and ADAM28 was determined by Western blot. Bioinformatic method was used to predict the target genes of miR-145. Antagonistic effect of ADAM28 over-expression on the inhibition of EMT by miR-145 was detected by Western blot. The relationship between miR-145 and ADAM28 was analyzed by dual-luciferase reporter assay. RESULTS: The expression level of miR-145 in M145 group was significantly up-regulated than that in MC group (P<0.05). The number of invasive cells in M145 group was 12.78±3.37, which was significantly lower than that in MC group (P<0.05). ADAM28 may be the target gene of miR-145. Compared with MC group, the protein expression of vimentin and ADAM28 in M145 group was significantly decreased (P<0.05), while the protein expression of E-cadherin was significantly increased (P<0.05).After ADAM28 over-expression, the protein expression of vimentin in the A-498 cells of M145 group was significantly increased (P<0.05), and the protein expression of E-cadherin was significantly decreased (P<0.05). The results of dual-lucife-irasei reporter assay showed that ADAM28 was a downstream target gene of miR-145. CONCLUSION: miR-145 may inhibit the expression of EMT-related proteins through the downstream target gene ADAM28 and inhibit the EMT process of renal cancer A-498 cells. 相似文献
190.
以茄子品种丰田一号为试材,研究了夏季剪枝对山地栽培茄子生长及品质的影响。试验结果表明,与对照相比,夏季剪枝对丰田一号的植株冠幅、茎粗、叶片大小等影响不显著,但剪枝后叶片鲜质量、干质量、叶绿素含量、优质果率及产量均显著提高(P<0.05),株高和劣质果率则显著降低,该研究为夏季剪枝技术在山地茄子栽培中的广泛应用提供了理论依据。 相似文献