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61.
62.
Zhou Yang Cao Leqing Guo Huidong Hong Yan Wang Ming Wang Ke Huang Xiaojun Chang Yingjun 《中国科学:生命科学英文版》2021,64(7):1087-1096
Acute graft-versus-host disease(a GVHD) is caused by allo-activated donor T cells infiltrating target organs. As a regulator of immune function, granulocyte colony-stimulating factor(G-CSF) has been demonstrated to relieve the a GVHD reaction.However, the role of G-CSF-primed donor Tcells in specific target organs is still unknown. In this study, we employed a classical MHC-mismatched transplantation mouse model(C57BL/6 into BALB/c) and found that recipient mice transplanted with GCSF-primed T cells exhibited prolonged survival compared with that of the PBS-treated group. This protective function against GVHD mediated by G-CSF-primed donor T cells was further confirmed by decreased clinical and pathological scores in this a GVHD mouse model, especially in the lung and gut. Moreover, we found that Tcells polarized towards Th2 cells and regulatory T cells were increased in specific target organs. In addition, G-CSF treatment inhibited inducible co-stimulator(ICOS) expression and increased the expression of tolerance-related genes in recipient mice. Our study provides new insight into the immune regulatory effects of G-CSF on T cell-mediated a GVHD, especially for its precise regulation in GVHD target organs. 相似文献
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64.
Li Zhengtu Li Yinhu Sun Ruilin Li Shaoqiang Chen Lingdan Zhan Yangqing Xie Mingzhou Yang Jiasheng Wang Yanqun Zhu Airu Gu Guoping Yu Le Li Shuaicheng Liu Tingting Chen Zhaoming Jian Wenhua Jiang Qian Su Xiaofen Gu Weili Chen Liyan Cheng Jing Zhao Jincun Lu Wenju Zheng Jinping Li Shiyue Zhong Nanshan Ye Feng 《中国科学:生命科学英文版》2021,64(12):2129-2143
Science China Life Sciences - Prolonged viral RNA shedding and recurrence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in coronavirus disease 2019 (COVID-19) patients have been... 相似文献
65.
Liu Xiaoxiao Zhang Li Thu Pyone Myat Min Wenjian Yang Peng Li Ji Li Ping Xu Xiaojun 《中国科学:生命科学英文版》2021,64(8):1295-1310
Science China Life Sciences - Despite the use of many types of chemotherapies for pancreatic cancer, optimal efficacy has not been obtained so far. Pancreatic cancer shows a high incidence of TP53... 相似文献
66.
Zilan Lv Dandan Yang Jie Li Min Hu Min Luo Xiaoqin Zhan Peipei Song Chen Liu Huili Bai Baolin Li Yang Yang Yingying Chen Qiong Shi Yaguang Weng 《Molecules and cells》2013,36(2):119-126
Transforming growth factor-β (TGF-β) is known to promote tumor migration and invasion. Bone morphogenetic proteins (BMPs) are members of the TGF-β family expressed in a variety of human carcinoma cell lines. The role of bone morphogenetic protein 9 (BMP9), the most powerful osteogenic factor, in osteosarcoma (OS) progression has not been fully clarified. The expression of BMP9 and its receptors in OS cell lines was analyzed by RT-PCR. We found that BMP9 and its receptors were expressed in OS cell lines. We further investigated the influence of BMP9 on the biological behaviors of OS cells. BMP9 overexpression in the OS cell lines 143B and MG63 inhibited in vitro cell migration and invasion. We further investigated the expression of a panel of cancer-related genes and found that BMP9 overexpression increased the phosphorylation of Smad1/5/8 proteins, increased the expression of ID1, and reduced the expression and activity of matrix metalloproteinase 9 (MMP9) in OS cells. BMP9 silencing induced the opposite effects. We also found that BMP9 may not affect the chemokine (C-X-C motif) ligand 12 (CXCL12)/C-X-C chemokine receptor type 4 (CXCR4) axis to regulate the invasiveness and metastatic capacity of OS cells. Interestingly, CXCR4 was expressed in both 143B and MG63 cells, while CXCL12 was only detected in MG63 cells. Taken together, we hypothesize that BMP9 inhibits the migration and invasiveness of OS cells through a Smad-dependent pathway by downregulating the expression and activity of MMP9. 相似文献
67.
Jixun Zhan Yuanxing Zhang Wenhui Liu Hongzhu Guo Dean Guo 《Biocatalysis and Biotransformation》2013,31(3):141-143
Directional modifications of resibufogenin 1 by Mucor subtilissimus and Pseudomonas aeruginosa were carried out. The substrate was hydroxylated at C-12 by M. subtilissimus AS 3.2454, from which a major product 12-hydroxyresibufogenin 2 was obtained. Then product 2 was dehydrogenated by P. aeruginosa AS 1.860, which resulted in a new compound 12β-hydroxy-3-keto-resibufogenin 3. 相似文献
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Dayu Yu Fuchao Xu Jonathan Valiente Siyuan Wang Jixun Zhan 《Journal of industrial microbiology & biotechnology》2013,40(1):159-168
A putative indigoidine biosynthetic gene cluster was located in the genome of Streptomyces chromofuscus ATCC 49982. The silent 9.4-kb gene cluster consists of five open reading frames, named orf1, Sc-indC, Sc-indA, Sc-indB, and orf2, respectively. Sc-IndC was functionally characterized as an indigoidine synthase through heterologous expression of the enzyme in both Streptomyces coelicolor CH999 and Escherichia coli BAP1. The yield of indigoidine in E. coli BAP1 reached 2.78 g/l under the optimized conditions. The predicted protein product of Sc-indB is unusual and much larger than any other reported IndB-like protein. The N-terminal portion of this enzyme resembles IdgB and the C-terminal portion is a hypothetical protein. Sc-IndA and/or Sc-IndB were co-expressed with Sc-IndC in E. coli BAP1, which demonstrated the involvement of Sc-IndB, but not Sc-IndA, in the biosynthetic pathway of indigoidine. The yield of indigoidine was dramatically increased by 41.4 % (3.93 g/l) when Sc-IndB was co-expressed with Sc-IndC in E. coli BAP1. Indigoidine is more stable at low temperatures. 相似文献
70.
Recent advances in nanotechnologies have led to wide use of nanomaterials in biomedical field. However, nanoparticles are found to interfere with protein misfolding and aggregation associated with many human diseases. It is still a controversial issue whether nanoparticles inhibit or promote protein aggregation. In this study, we used molecular dynamics simulations to explore the effects of three kinds of carbon nanomaterials including graphene, carbon nanotube and C60 on the aggregation behavior of islet amyloid polypeptide fragment 22–28 (IAPP22–28). The diverse behaviors of IAPP22–28 peptides on the surfaces of carbon nanomaterials were studied. The results suggest these nanomaterials can prevent β-sheet formation in differing degrees and further affect the aggregation of IAPP22–28. The π–π stacking and hydrophobic interactions are different in the interactions between peptides and different nanoparticles. The subtle differences in the interaction are due to the difference in surface curvature and area. The results demonstrate the adsorption interaction has competitive advantages over the interactions between peptides. Therefore, the fibrillation of IAPP22–28 may be inhibited at its early stage by graphene or SWCNT. Our study can not only enhance the understanding about potential effects of nanomaterials to amyloid formation, but also provide valuable information to develop potential β-sheet formation inhibitors against type II diabetes. 相似文献