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961.
杜鹃花属植物扦插繁殖研究进展 总被引:3,自引:0,他引:3
我国有着丰富的杜鹃花资源,但有关其繁殖应用的研究还具有一定的局限。种子育苗耗时长,组培育苗成本和技术要求高,都不适于杜鹃花属植物的大面积生产。扦插繁殖快,还可保持母本的优良性状。从插条的选择,准备,插条的生根激素处理,扦插基质的选择,外界环境条件对扦插成活率的影响及扦插后的养护管理等六个方面对杜鹃的扦插繁殖技术的研究进行综述,以期推进杜鹃花属植物,尤其是中国野生杜鹃的引种驯化和大面积的推广应用。 相似文献
962.
自2006年诱导多能干细胞(iPS)技术诞生以来,采用病毒等载体进行的诱导方法已取得了成功,但是其致瘤性的影响限制了病毒载体的推广与应用,而采用非病毒载体诱导iPS细胞成为研究的热点. 本研究通过两个启动子的独立启动,构建了带有绿色荧光标记的OCT4/SOX2共表达诱导载体(pOct4/Sox2-EGFP). 将该载体转染HEK 293FT 细胞后,阳性克隆明显表达绿色荧光,并通过RT-PCR,免疫荧光等方法证明其中的转录因子OCT4和SOX2能在转染细胞中高效表达,同时诱导受体细胞中内源NANOG的转录表达. 本研究说明OCT4/SOX2共表达载体能激活NANOG基因的内源表达,暗示着非病毒不整合载体pOct4/Sox2-EGFP本身或与其它转录因子和小分子结合可用于诱导成体细胞的重编程. 因此,本研究为下一步应用质粒载体诱导体细胞重编程为iPS细胞的研究奠定了工作基础. 相似文献
963.
间充质干细胞MSCs(mesenchymal stem cells)与肿瘤细胞间的相互作用是近年来肿瘤领域的研究热点之一.MSCs是一种多能干细胞,具有分化为成骨细胞、软骨细胞、脂肪细胞、纤维母细胞或肌肉细胞等多种间充质细胞的能力.MSCs在肿瘤细胞中表现出的归巢和转移能力为其成为潜在的抗肿瘤工具奠定了基础,MSCs转移到肿瘤细胞后参与重塑肿瘤微环境,并对其增殖、侵袭和转移等生物学行为产生重要影响.MSCs重塑肿瘤微环境后对肿瘤细胞的增殖究竟是促进还是抑制,相关文献报道有很大的争议.基于相关研究近况,主要综述骨髓间充质干细胞BMSCs(bone marrow derived mesenchymal stem cells)参与重塑肿瘤微环境对肿瘤细胞增殖的影响,并就已知的分子机理做一简要介绍. 相似文献
964.
2006年Takahashi研究小组成功地将小鼠的胚胎成纤维细胞和鼠尾成纤维细胞重编成为诱导性多能干细胞(iPSC),开创了体细胞重编程的全新方法,所得iPSC具有和胚胎干细胞相似的生物学特性,不仅解决了人类胚胎干细胞研究所面临的伦理学困境和免疫排斥问题,而且进一步深化了对细胞多能性和基因组重编程的认识,再次掀起了干细胞研究的热潮。iPSC结合基因治疗和细胞治疗的成果已经应用到动物疾病模型上。iPSC能够自我更新并维持未分化状态,可分化为3个胚层来源的所有细胞,参与形成机体所有组织和器官,体外定向诱导能够分化出各种成体细胞,在理论研究和临床应用等方面都极具应用价值。但iPSC技术也存在一系列问题需要研究解决。 相似文献
965.
The ethical issues and public concerns regarding the use of embryonic stem (ES) cells in human therapy have motivated considerable
research into the generation of pluripotent stem cell lines from non-embryonic sources. Numerous reports have shown that pluripotent
cells can be generated and derived from germline stem cells (GSCs) in mouse and human testes during in vitro cultivation. The gene expression patterns of these cells are similar to those of ES cells and show the typical self-renewal
and differentiation patterns of pluripotent cells in vivo and in vitro. However, the mechanisms underlying the spontaneous dedifferentiation of GSCs remain to be elucidated. Studies to identify
master regulators in this reprogramming process are of critical importance for understanding the gene regulatory networks
that sustain the cellular status of these cells. The results of such studies would provide a theoretical background for the
practical use of these cells in regenerative medicine. Such studies would also help elucidate the molecular mechanisms underlying
certain diseases, such as testicular germ cell tumors. 相似文献
966.
Hematopoietic stem cells (HSCs) are used therapeutically for hematological diseases and may also serve as a source for nonhematopoietic
tissue engineering in the future. In other cell types, ion channels have been investigated as potential targets for the regulation
of proliferation and differentiation. However, the ion channels of HSCs remain elusive. Here, we functionally characterized
the ion channels of CD34+ cells from human peripheral blood. Using fluorescence-activated cell sorting, we confirmed that the CD34+ cells also express CD45 and CD133. In the CD34+/CD45+/CD133high HSCs, RT-PCR of 58 ion channel mRNAs revealed the coexpression of Kv1.3, Kv7.1, Nav1.7, TASK2, TALK2, TWIK2, TRPC4, TRPC6,
TRPM2, TRPM7, and TRPV2. Whole-cell patch clamp recordings identified voltage-gated K+ currents (putatively Kv1.3), pH-sensitive TASK2-like back-ground K+ currents, ADP-ribose-activated TRPM2 currents, temperature-sensitive TRPV2-like currents, and diacylglycerol-analogue-activated
TRPC6-like currents. Our results lend new insight into the physiological role of ion channels in HSCs, the specific implications
of which require further investigation. 相似文献
967.
Andersen DC Kortesidis A Zannettino AC Kratchmarova I Chen L Jensen ON Teisner B Gronthos S Jensen CH Kassem M 《Molecules and cells》2011,32(2):133-142
Human mesenchymal stem cells (hMSC) are currently being introduced for cell therapy, yet, antibodies specific for native and
differentiated MSCs are required for their identification prior to clinical use. Herein, high quality antibodies against MSC
surface proteins were developed by immunizing mice with hMSC, and by using a panel of subsequent screening methods. Flow cytometry
analysis revealed that 83.5, 1.1, and 8.5% of primary cultures of hMSC were double positive for STRO-1 and either of DJ 3,
9, and 18, respectively. However, none of the three DJ antibodies allowed enrichment of clonogenic hMSC from BMMNCs as single
reagents. Using mass-spectrometric analysis, we identified the antigen recognised by DJ3 as CD44, whereas DJ9 and DJ18 recognized
HLA-DRB1 and Collagen VI, respectively. The identified proteins were highly expressed throughout in vitro osteogenic- and adipogenic differentiation. Interestingly, undifferentiated cells revealed a sole cytoplasmic distribution
pattern of Collagen VI, which however changed to an extracellular matrix appearance upon osteogenic- and adipogenic differentiation.
In relation to this, we found that STRO-1+/−/Collagen VI− sorted hMSC contained fewer differentiated alkaline phosphatase+ cells compared to STRO-1+/−/Collagen VI+ hMSC, suggesting that Collagen VI on the cell membrane exclusively defines differentiated MSCs. In conclusion, we have generated
a panel of high quality antibodies to be used for characterization of MSCs, and in addition our results may suggest that the
DJ18 generated antibody against Collagen VI can be used for negative selection of cultured undifferentiated MSCs. 相似文献
968.
红掌茎段侧芽离体快繁技术研究 总被引:2,自引:0,他引:2
以红掌嫩茎为外植体,诱导侧芽萌发,并进行增殖和生根培养,研究不同生长调节剂浓度配比对茎段侧芽萌发、增殖、无菌苗生根的影响以及增殖培养过程中愈伤组织的抑制等因素。结果表明,侧芽诱导的适宜培养基为MS+6-BA 2.0 mg/L+NAA 0.5 mg/L,萌发率达87.5%;最适增殖培养基为MS+6-BA 0.8 mg/L+NAA 0.2 mg/L+VB2 8.0 mg/L,增殖系数3.8;最适生根培养基为1/2MS+NAA 0.5 mg/L,生根率98%;在增殖培养基中添加适量VB2能较好地抑制愈伤组织的生成,防止愈伤组分织分化形成芽,从而达到以芽繁芽的目的。 相似文献
969.
970.