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991.
Teizo Yoshimura O. M. Zack Howard Toshihiro Ito Masaki Kuwabara Akihiro Matsukawa Keqiang Chen Ying Liu Mingyong Liu Joost J. Oppenheim Ji Ming Wang 《PloS one》2013,8(3)
MCP-1/CCL2 plays an important role in the initiation and progression of cancer. Since tumor cells produce MCP-1, they are considered to be the main source of this chemokine. Here, we examined whether MCP-1 produced by non-tumor cells affects the growth and lung metastasis of 4T1 breast cancer cells by transplanting them into the mammary pad of WT or MCP-1−/− mice. Primary tumors at the injected site grew similarly in both mice; however, lung metastases were markedly reduced in MCP-1−/− mice, with significantly longer mouse survival. High levels of MCP-1 mRNA were detected in tumors growing in WT, but not MCP-1−/− mice. Serum MCP-1 levels were increased in tumor-bearing WT, but not MCP-1−/− mice. Transplantation of MCP-1−/− bone marrow cells into WT mice did not alter the incidence of lung metastasis, whereas transplantation of WT bone marrow cells into MCP-1−/− mice increased lung metastasis. The primary tumors of MCP-1−/− mice consistently developed necrosis earlier than those of WT mice and showed decreased infiltration by macrophages and reduced angiogenesis. Interestingly, 4T1 cells that metastasized to the lung constitutively expressed elevated levels of MCP-1, and intravenous injection of 4T1 cells producing a high level of MCP-1 resulted in increased tumor foci in the lung of WT and MCP-1−/− mice. Thus, stromal cell-derived MCP-1 in the primary tumors promotes lung metastasis of 4T1 cells, but tumor cell-derived MCP-1 can also contribute once tumor cells enter the circulation. A greater understanding of the source and role of this chemokine may lead to novel strategies for cancer treatment. 相似文献
992.
Langqing Zeng Haifeng Wei Yanjie Liu Wen Zhang Yao Pan Wei Zhang Changqing Zhang Bingfang Zeng Yunfeng Chen 《PloS one》2015,10(5)
BackgroundThe biomechanical characteristics of midshaft clavicular fractures treated with titanium elastic nail (TEN) is unclear. This study aimed to present a biomechanical finite element analysis of biomechanical characteristics involved in TEN fixation and reconstruction plate fixation for midshaft clavicular fractures.MethodsFinite element models of the intact clavicle and of midshaft clavicular fractures fixed with TEN and with a reconstruction plate were built. The distal clavicle displacement, peak stress, and stress distribution on the 3 finite element models were calculated under the axial compression and cantilever bending.ResultsIn both loading configurations, TEN generated the highest displacement of the distal clavicle, followed by the intact clavicle and the reconstruction plate. TEN showed higher peak bone and implant stresses, and is more likely to fail in both loading configurations compared with the reconstruction plate. TEN led to a stress distribution similar to that of the intact clavicle in both loading configurations, whereas the stress distribution with the reconstruction plate was nonphysiological in cantilever bending.ConclusionsTEN is generally preferable for treating simple displaced fractures of the midshaft clavicle, because it showed a stress distribution similar to the intact clavicle. However, TEN provides less stability, and excessive exercise of and weight bearing on the ipsilateral shoulder should be avoided in the early postoperative period. Fixation with a reconstruction plate was more stable but showed obvious stress shielding. Therefore, for patients with a demand for early return to activity, reconstruction plate fixation may be preferred. 相似文献
993.
994.
Bing Liu Zhaohui Wan Baowei Sheng Yong Lin Tian Fu Qingdi Zeng Congcong Qi 《BMC pulmonary medicine》2017,17(1):214
Background
Previous studies show that overexpression of EMMPRIN involved in the malignant biological behavior of tumors. This investigation was to disclose the expression status of EMMPRIN in non-small cell lung cancer (NSCLC) and its clinical value for the diagnosis of NSCLC.Methods
The expression of EMMPRIN was examined using immunohistochemistry and enzyme-linked immunosorbent assay. The clinical value of EMMPRIN was evaluated by drawing a receiver operating characteristic (ROC) curve.Results
NSCLC tissues and serum exhibited higher expression levels of EMMPRIN than the normal control (p?<?0.05), and the expression of the EMMPRIN was significantly associated with lymphatic invasion and advanced stage of NSCLC (p?<?0.05). ROC curve suggested that the threshold level of serum EMMPRIN for distinguishing NSCLC from control group was 80.3 pg/mL, and displayed a sensitivity of 97.22% and a specificity of 95%. And higher EMMPRIN expression in serum and tissues appeared to be risk factors for NSCLC development (risk ratio =1.56 and 1.1).Conclusion
Overexpression of EMMPRIN was associated with lymphatic metastasis and advanced stage of NSCLC and test of serum EMMPRIN contributes to the NSCLC diagnosis.995.
Xiaohui Chen Yanjie Fan Wei Zhang Zhenqi Tian Jian Liu Kuijun Zhao 《Applied Entomology and Zoology》2017,52(3):491-495
Nymphs of Aphis glycines Matsumura were individually reared to adults in the laboratory on detached leaf discs of Trifolium repens L. (white clover) mounted on agar medium. Adults of A. glycines were fed T. repens within small clip cages in the field. Development, reproduction and intrinsic rates of increase of A. glycines were studied. These data were compared to those of controls fed known host plants including cultivated soybean Glycine max (L.) Merr. and the wild soybean species Glycine soja Sieb & Zucc. The results demonstrated that nymphs of A. glycines successfully developed into adults and reproduced efficiently when reared on T. repens in the laboratory. The lower development temperature threshold for nymphs fed T. repens was estimated as 8.27 °C, and the effective cumulative temperature for A. glycines development from nymph to adult was 90.91 degree-days. Adults of A. glycines could also survive on T. repens in the field, but only a few nymphs were produced. 相似文献
996.
Zhao Wei Fan Aili Tarcz Sylwia Zhou Kang Yin Wen-Bing Liu Xiao-Qing Li Shu-Ming 《Applied microbiology and biotechnology》2017,101(5):1989-1998
Applied Microbiology and Biotechnology - The fungal cyclic dipeptide prenyltransferase FtmPT1 from Aspergillus fumigatus catalyzes a regular C2-prenylation of brevianamide F (cyclo-l-Trp-l-Pro) and... 相似文献
997.
We constructed a recombinant gene encoding an immunoglobulin (Ig) heavy chain consisting of the variable region from the phosphorylcholine (PC)-specific secreting myeloma MOPC167 and the epsilon constant region from SJL mice. This gene, cloned into the shuttle vector pSV2gpt, was transfected into J558L myeloma cells, and stable transformants that expressed the epsilon gene were cloned. The IgE heavy chain in these transformants is associated with the endogenous lambda light chain and is secreted as an intact IgE molecule. However, the secreted IgE does not bind to PC conjugated to bovine serum albumin (PC-BSA). The MOPC167 kappa chain gene was cloned into the shuttle vector pSV2neo and was transfected into the epsilon heavy-chain transformant. Stable transformants were cloned that expressed both the epsilon heavy chain and the kappa light chain. IgE secreted from such a transformant was shown to bind to PC-BSA. Both types of secreted recombinant IgE bound to rat basophilic leukemia (RBL) cells, but only the IgE produced by the cell line transformed with the MOPC167 kappa gene could be cross-linked with PC-BSA to cause serotonin release. 相似文献
998.
Jieyuan Zhang Huijun Chen Zhaoxia Duan Kuijun Chen Zeng Liu Lu Zhang Dongdong Yao Bingcang Li 《Molecular neurobiology》2017,54(2):943-953
Inflammatory response following spinal cord injury (SCI) is important in regulation of the repair process. Olfactory ensheathing cells (OECs) and Schwann cells (SCs) are important donor cells for repairing SCI in different animal models. However, synergistic or complementary effects of co-transplantation of both cells for this purpose have not been extensively investigated. In the present study, we investigated the effects of co-transplantation of OECs and SCs on expression of pro- or anti-inflammatory factor and polarization of macrophages in the injured spinal cord of rats. Mixed cell suspensions containing OECs and SCs were transplanted into the injured site at 7 days after contusion at the vertebral T10 level. Compared with the DMEM, SC, or OEC group, the co-transplantation group had a more extensive distribution of the grafted cells and significantly reduced number of astrocytes, microglia/macrophage infiltration, and expression of chemokines (CCL2 and CCL3) at the injured site. The co-transplantation group also significantly increased arginase+/CD206+ macrophages (IL-4) and decreased iNOS+/CD16/32+ macrophages (IFN-γ), which was followed by higher IL-10 and IL-13 and lower IL-6 and TNF-α in their expression levels, a smaller cystic cavity area, and improved motor functions. These results indicate that OEC and SC co-transplantation could promote the shift of the macrophage phenotype from M(IFN-γ) to M(IL-4), reduce inflammatory cell infiltration in the injured site, and regulate inflammatory factors and chemokine expression, which provide a better immune environment for SCI repair. 相似文献
999.
Human mononuclear phagocyte activation antigens 总被引:2,自引:0,他引:2
R F Todd I F Mizukami S D Vinjamuri R D Trochelman W W Hancock D Y Liu 《Blood cells》1990,16(1):167-79; discussion 180-2
Activation of mononuclear phagocytes causes changes in plasma membrane composition that include the expression of surface antigens and receptors. Monoclonal antibody technology has made it possible to identify and characterize newly expressed surface antigens. Among these "activation antigens" is a glycoprotein, Mo3, which (among hematopoietic cells) is selectively expressed by human mononuclear phagocytes that have been exposed to inflammatory factors in vitro and in vivo. Progress toward a functional and structural analysis of Mo3 is described. 相似文献
1000.
CD3ε和PMA对fas基因转录调控作用的研究 总被引:2,自引:0,他引:2
研究了CD3ε和PMA对细胞凋亡基因fas的转录调控作用.根据已知的人fas基因5'上游序列设计引物,用PCR法从人胸腺细胞基因组DNA中扩增出fas5'上游长为446bp的启动子片段.将此片段定向克隆到以虫荧光素酶为报告基因的真核细胞表达载体pXP2中.经限制性内切酶酶切鉴定及序列测定分析表明此重组表达质粒DNA的结构和序列正确.用此质粒(pXP2-fasup)瞬时转染人JurkatT淋巴细胞,分析报告基因的表达水平.结果表明fas基因上游-506到-60的区域有弱启动子活性,约是阴性对照的1.5倍.抗CD3ε抗体和PMA处理均可增强fas启动子的活性,促进报告基因的表达,其虫荧光素酶活性分别是未经处理的pXP2-fasup转染细胞的1.7倍和3.3倍,但二者没有协同作用.PKC的抑制剂staurosporine和PTK的抑制剂herbimycinA可抑制PMA诱导的fas基因转录,使虫荧光素酶基因的表达降至未用PMA处理的水平.但PTK的另一种抑制剂genistein可与PMA发挥协同作用,上调fas基因的转录,使虫荧光素酶活性增加到5倍.这些结果为阐明CD3ε及PMA介导T淋巴细胞激活和凋亡的分子机制 相似文献