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961.
962.
Alison J. Kriegel Yi Fang Yong Liu Zhongmin Tian Domagoj Mladinov Isaac R. Matus Xiaoqiang Ding Andrew S. Greene Mingyu Liang 《Nucleic acids research》2010,38(22):8338-8347
We reported previously an approach for identifying microRNA (miRNA)-target pairs by combining miRNA and proteomic analyses. The approach was applied in the present study to examine human renal epithelial cells treated with transforming growth factor β1 (TGFβ1), a model of epithelial–mesenchymal transition important for the development of renal interstitial fibrosis. Treatment of human renal epithelial cells with TGFβ1 resulted in upregulation of 16 miRNAs and 18 proteins and downregulation of 17 miRNAs and 16 proteins. Of the miRNAs and proteins that exhibited reciprocal changes in expression, 77 pairs met the sequence criteria for miRNA–target interactions. Knockdown of miR-382, which was up-regulated by TGFβ1, attenuated TGFβ1-induced loss of the epithelial marker E-cadherin. miR-382 was confirmed by 3′-untranslated region reporter assay to target five genes that were downregulated at the protein level by TGFβ1, including superoxide dismutase 2 (SOD2). Knockdown of miR-382 attenuated TGFβ1-induced downregulation of SOD2. Overexpression of SOD2 ameliorated TGFβ1-induced loss of the epithelial marker. The study provided experimental evidence in the form of reciprocal expression at the protein level for a large number of predicted miRNA-target pairs and discovered a novel role of miR-382 and SOD2 in the loss of epithelial characteristics induced by TGFβ1. 相似文献
963.
Myricaria laxiflora, a riparian plant that naturally occurs in the riverbanks of the Yangtze River Valley, has become extinct across its entire geographical distribution range in the wild due to the construction of the Three Gorges Dam. The allozyme variation of M. laxiflora populations was investigated in the present study. Mean number of alleles per locus (A) was 2.35, and the observed heterozygosity (Ho) and expected heterozygosity (He) were 0.35 and 0.30, respectively. Six populations showed significant excesses of heterozygotes based on the examination of a multilocus fixation index (FIS). The population genetic divergence of M. laxiflora is high (GST = 0.144 and ?B = 0.131) and the analysis of molecular variance analysis shows that 19.71% of the total genetic variation is caused by the difference between populations. Based on the obtained genetic information, six management units have been identified, all of which are expected to enhance the effective management of the remaining and transplanted individuals of this endangered species in the future. 相似文献
964.
Choong Hyun Lee Ki-Yeon Yoo Ok Kyu Park Jung Hoon Choi Il-Jun Kang Eunjoo Bae Sung Koo Kim In Koo Hwang Moo-Ho Won 《Molecules and cells》2010,29(4):373-378
Phosphorylated extracellular signal-regulated kinase (pERK) mediates neuronal synaptic plasticity, long-term potentiation,
and learning and memory in the hippocampus. In this study, we examined pERK1/2 immunoreactivity and its protein level in the
gerbil hippocampus at various ages. In the postnatal month 1 (PM 1) group, very weak pERK1/2 immunoreactivity was detected
in the hippocampus. In the CA1 region, pERK1/2 immunoreactivity was considerably increased in the stratum pyramidale in the
PM 6 group. Thereafter, pERK1/2 immunoreactivity was decreased. In the CA2/3 region, pERK1/2 immunoreactivity increased in
an age-dependent manner until PM 12. Thereafter, numbers of pERK1/2-immunoreactive neurons were decreased. However, in the
mossy fiber zone, pERK1/2 immunostaining became stronger with age. In the dentate gyrus, a few pERK1/2-immunoreactive cells
were observed until PM 12. In the PM 18 and 24 groups, numbers of pERK1/2-immunoreactive cells were increased, especially
in the polymorphic layer. In Western blot analysis, pERK1/2 level in the gerbil hippocampus was increased with age. These
results indicate that total pERK1/2 levels are increased in the hippocampus with age. However pERK1/2 immunoreactivity in
subregions of the gerbil hippocampus was changed with different pattern during normal aging. 相似文献
965.
Guang‐Zhen Jin Su‐Jin Cho Young‐S Lee Myeong‐Ok Kim Dong‐Woo Cho Il‐Keun Kong 《Cell biology international》2010,34(1):135-140
MSCs (mesenchymal stem cells) derived from the bone marrow have shown to be a promising source of stem cells in a therapeutic strategy of neurodegenerative disorder. Also, MSCs can enhance the TH (tyrosine hydroxylase) expression and DA (dopamine) content in catecholaminergic cells by in vitro co‐culture system. In the present study, we investigated the effect of intrastriatal grafts of MSCs on TH protein and gene levels and DA content in adult intact rats. When MSCs were transplanted into the striatum of normal rats, the grafted striatum not only had significantly higher TH protein and mRNA levels, but also significantly higher DA content than the untransplanted striatum. Meanwhile, the grafted MSCs differentiated into neurons, astrocytes and oligodendrocytes; however, TH‐positive cells could not be detected in our study. These experimental results offer further evidence that MSCs are a promising candidate for treating neurodegenerative diseases such as Parkinson's disease. 相似文献
966.
Jin Woo Park Sang Kyoon Kim Taslim Ahmed Al-Hilal Ok Cheol Jeon Hyun Tae Moon Youngro Byun 《Biotechnology and Bioprocess Engineering》2010,15(1):66-75
Advances in biotechnology, gene manipulation, and protein engineering for macromolecule drugs, such as insulin, parathyroid
hormone (PTH), calcitonin, human growth hormone, erythropoietin (EPO), and peptide YY (PYY) allow commercial production in
large scale for diverse therapeutic uses. Other macromolecules, such as mucopolysaccharide heparin, have expanded markets
through improvements in their pharmacokinetic and pharmacological effects. However, most products are available only as injectable
forms and are limited to patients with no alternative therapeutic choices. Orally available macromolecule formulations are
still unmet needs for improving patient compliance and expanding administration paradigms and indications. Oral delivery technologies
including carrier systems, absorption enhancers, protease inhibitors, and modification by conjugating transporter or receptor
recognition molecules have been developed and some are undergoing clinical studies. In this review, we discuss major obstacles
for oral absorption of macromolecule drugs and summarize recent strategies to overcome the huddles related to enhancing intestinal
permeation. 相似文献
967.
Zhen Xing Zhang Qi Xin Zheng Yong Chao Wu Ding Jun Hao 《Biotechnology and Bioprocess Engineering》2010,15(4):545-551
In this study, we evaluated the behavior of neural stem cells (NSCs) using a new peptide hydrogel scaffold named IKVAVmx,
which was made by mixing self-assembling peptide RADA16 and designer peptide RADA16-IKVAV solutions. NSCs derived from rat
cerebral cortex were culture-expanded in neuorobasal medium and seeded on the RADA16 and IKVAVmx hydrogels. Cells could penetrate
the hydrogels and form a 3D cellular network. Compared to pure RADA16 scaffold, we found that IKVAVmx scaffold significantly
promoted cell proliferation and stimulated cell migration into the 3D scaffold. Moreover, Immunocytochemistry and Western
blot analysis indicated that the differentiation ratio of neurons from NSCs in IKVAVmx scaffold was higher than that in pure
RADA16 scaffold. These results suggested that this new hydrogel scaffold provided an ideal substrate for NSCs 3D culture and
suggested its further application for neural tissue engineering. 相似文献
968.
969.
Anthony Wynshaw-Boris Tiziano Pramparo Yong Ha Youn Shinji Hirotsune 《Seminars in cell & developmental biology》2010,21(8):823-830
Lissencephaly is a severe human neuronal migration defect characterized by a smooth cerebral surface, mental retardation and seizures. The two most common genes mutated in patients with lissencephaly are LIS1 and DCX. LIS1 was the first gene cloned that was important for neuronal migration in any organism, and heterozygous mutations or deletions of LIS1 are found in the majority of patients with lissencephaly, while DCX mutations were found in males with X-linked lissencephaly. In this review, we will discuss how an understanding of the molecular and cellular pathways disrupted in model organisms with Lis1 and Dcx mutations or knock-down not only provide insights into the normal processes of neuronal migration, including neurogenesis, but they also may lead to potential novel therapeutic strategies for these severe cortical malformations. 相似文献