全文获取类型
收费全文 | 86489篇 |
免费 | 9996篇 |
国内免费 | 1142篇 |
专业分类
电工技术 | 4381篇 |
技术理论 | 1篇 |
综合类 | 1373篇 |
化学工业 | 23515篇 |
金属工艺 | 1794篇 |
机械仪表 | 2611篇 |
建筑科学 | 4060篇 |
矿业工程 | 211篇 |
能源动力 | 7904篇 |
轻工业 | 7728篇 |
水利工程 | 537篇 |
石油天然气 | 342篇 |
武器工业 | 86篇 |
无线电 | 12494篇 |
一般工业技术 | 19320篇 |
冶金工业 | 1298篇 |
原子能技术 | 235篇 |
自动化技术 | 9737篇 |
出版年
2025年 | 7篇 |
2024年 | 1007篇 |
2023年 | 916篇 |
2022年 | 1610篇 |
2021年 | 2349篇 |
2020年 | 4721篇 |
2019年 | 7056篇 |
2018年 | 5731篇 |
2017年 | 6265篇 |
2016年 | 5945篇 |
2015年 | 5307篇 |
2014年 | 5761篇 |
2013年 | 6012篇 |
2012年 | 5422篇 |
2011年 | 5669篇 |
2010年 | 4268篇 |
2009年 | 3863篇 |
2008年 | 3638篇 |
2007年 | 3654篇 |
2006年 | 3265篇 |
2005年 | 2660篇 |
2004年 | 2294篇 |
2003年 | 2162篇 |
2002年 | 2114篇 |
2001年 | 1865篇 |
2000年 | 1516篇 |
1999年 | 906篇 |
1998年 | 362篇 |
1997年 | 255篇 |
1996年 | 217篇 |
1995年 | 130篇 |
1994年 | 135篇 |
1993年 | 95篇 |
1992年 | 88篇 |
1991年 | 50篇 |
1990年 | 43篇 |
1989年 | 45篇 |
1988年 | 36篇 |
1987年 | 27篇 |
1986年 | 27篇 |
1985年 | 30篇 |
1984年 | 23篇 |
1983年 | 15篇 |
1982年 | 13篇 |
1981年 | 8篇 |
1980年 | 10篇 |
1979年 | 7篇 |
1978年 | 6篇 |
1975年 | 6篇 |
1951年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 156 毫秒
61.
Magda Aleksandra Pawlicka Szymon Zmorzyski Sylwia Popek-Marciniec Agata Anna Filip 《International journal of molecular sciences》2022,23(20)
This study aimed to evaluate the safety and potential use of soy isoflavones in the treatment of skin problems, difficult-to-heal wounds and postoperative scars in women after the oncological treatment of breast cancer. The effects of different concentrations of genistein as a representative of soy isoflavonoids on MCF-7 tumor cells and BJ skin fibroblasts cultured in vitro were assessed. Genistein affects both healthy dermal BJ fibroblasts and cancerous MCF-7 cells. The effect of the tested isoflavonoid is closely related to its concentration. High concentrations of genistein destroy MCF-7 cancer cells, regardless of the exposure time, with a much greater effect on reducing cancer cell numbers at longer times (48 h). Lower concentrations of genistein (10 and 20 μM) increase the abundance of dermal fibroblasts. However, higher concentrations of genistein (50 μM and higher) are detrimental to fibroblasts at longer exposure times (48 h). Our studies indicate that although genistein shows high potential for use in the treatment of skin problems, wounds and surgical scars in women during and after breast cancer treatment, it is not completely safe. Introducing isoflavonoids to treatment requires further research into their mechanisms of action at the molecular level, taking into account genetic and immunological aspects. It is also necessary to conduct research in in vivo models, which will allow for eliminating adverse side effects of therapy. 相似文献
62.
Shuailong Zheng Li Li Helin Zhou Xujia Zhang Xiaoli Xu Dinghui Dai Siyuan Zhan Jiaxue Cao Jiazhong Guo Tao Zhong Linjie Wang Hongping Zhang 《International journal of molecular sciences》2022,23(21)
The proliferation and differentiation of mammalian skeletal muscle satellite cells (MuSCs) are highly complicated. Apart from the regulatory signaling cascade driven by the protein-coding genes, non-coding RNAs such as microRNAs (miRNA) and circular RNAs (circRNAs) play essential roles in this biological process. However, circRNA functions in MuSCs proliferation and differentiation remain largely to be elucidated. Here, we screened for an exonic circTCF4 based on our previous RNA-Seq data, specifically expressed during the development of the longest dorsal muscle in goats. Subsequently, the circular structure and whole sequence of circTCF4 were verified using Sanger sequencing. Besides, circTCF4 was spatiotemporally expressed in multiple tissues from goats but strikingly enriched in muscles. Furthermore, circTCF4 suppressed MuSCs proliferation and differentiation, independent of AGO2 binding. Finally, we conducted Poly(A) RNA-Seq using cells treated with small interfering RNA targeting circTCF4 and found that circTCF4 would affect multiple signaling pathways, including the insulin signaling pathway and AMPK signaling pathway related to muscle differentiation. Our results provide additional solid evidence for circRNA regulating skeletal muscle formation. 相似文献
63.
64.
Aurelie Dos Santos Ning Lyu Alis Balayan Rob Knight Katherine Sun Zhuo Yuzhao Sun Jianjiang Xu Martha L. Funderburgh James L. Funderburgh Sophie X. Deng 《International journal of molecular sciences》2022,23(21)
In addition to their therapeutic potential in regenerative medicine, human corneal stromal stem cells (CSSCs) could serve as a powerful tool for drug discovery and development. Variations from different donors, their isolation method, and their limited life span in culture hinder the utility of primary human CSSCs. To address these limitations, this study aims to establish and characterize immortalized CSSC lines (imCSSC) generated from primary human CSSCs. Primary CSSCs (pCSSC), isolated from human adult corneoscleral tissue, were transduced with ectopic expression of hTERT, c-MYC, or the large T antigen of the Simian virus 40 (SV40T) to generate imCSSC. Cellular morphology, proliferation capacity, and expression of CSSCs specific surface markers were investigated in all cell lines, including TNFAIP6 gene expression levels in vitro, a known biomarker of in vivo anti-inflammatory efficacy. SV40T-overexpressing imCSSC successfully extended the lifespan of pCSSC while retaining a similar morphology, proliferative capacity, multilineage differentiation potential, and anti-inflammatory properties. The current study serves as a proof-of-concept that immortalization of CSSCs could enable a large-scale source of CSSC for use in regenerative medicine. 相似文献
65.
Yoshihisa Ohashi Kentaro Uchida Kensuke Fukushima Masashi Satoh Tomohisa Koyama Maho Tsuchiya Hiroki Saito Katsufumi Uchiyama Naonobu Takahira Gen Inoue Masashi Takaso 《International journal of molecular sciences》2022,23(21)
The pathophysiology of early-stage hip osteoarthritis (EOA) is not fully understood. Although a previous study in an age-unmatched cohort reported that the number of macrophages was increased in knee EOA compared to late OA (LOA), it remained unclear whether increased macrophages in EOA accurately reflect EOA pathology. We investigated the differences in CD14 expression levels between EOA and LOA using age-unmatched and -matched cohorts. Synovial tissues were obtained from 34 EOA (Tönnis grades 0 and 1) and 80 LOA (Tönnis grades 2 and 3) patients. To correct for differences in demographics between patients with LOA and EOA, we also created propensity score-matched cohorts (16 EOA and 16 LOA). CD14 expression and its association with pain was estimated in LOA and EOA before and after propensity matching. We performed flow cytometry on tissues from the 16 patients, with 8 from each group, to assess for CD14+ subsets in the cells. The CD14 expression in EOA was higher than that in LOA both before and after propensity matching. The proportion of CD14high subsets in EOA was higher than that in LOA. The CD14 expression was associated with pain in EOA before matching. However, no difference was observed between the pain and CD14 expression after matching in EOA. The increased CD14 expression and the proportion of CD14high subsets may be important features associated with hip EOA pathology. To accurately compare early and late OA, the analysis of a propensity score-matched cohort is necessary. 相似文献
66.
Daniel L. Pouliquen Marine Malloci Alice Boissard Ccile Henry Catherine Guette 《International journal of molecular sciences》2022,23(22)
Curcumin exhibits both immunomodulatory properties and anticarcinogenic effects which have been investigated in different experimental tumor models and cancer types. Its interactions with multiple signaling pathways have been documented through proteomic studies on malignant cells in culture; however, in vivo approaches are scarce. In this study, we used a rat model of highly invasive peritoneal mesothelioma to analyze the residual tumor proteomes of curcumin-treated rats in comparison with untreated tumor-bearing rats (G1) and provide insights into the modifications in the tumor microenvironment/malignant cell crosstalk. The cross-comparing analyses of the histological sections of residual tumors from two groups of rats given curcumin twice on days 21 and 26 after the tumor challenge (G2) or four times on days 7, 9, 11 and 14 (G3), in comparison with G1, identified a common increase in caveolin-1 which linked with significant abundance changes affecting 115 other proteins. The comparison of G3 vs. G2 revealed additional features for 65 main proteins, including an increase in histidine-rich glycoprotein and highly significant abundance changes for 22 other proteins regulating the tumor microenvironment, linked with the presence of numerous activated T cells. These results highlight new features in the multiple actions of curcumin on tumor microenvironment components and cancer cell invasiveness. 相似文献
67.
Jin-Ho Park Eun-Byeol Koh Young-Jin Seo Hye-Seong Oh Ju-Yeong Won Sun-Chul Hwang June-Ho Byun 《International journal of molecular sciences》2022,23(22)
Tiron is a potent antioxidant that counters the pathological effects of reactive oxygen species (ROS) production due to oxidative stress in various cell types. We examined the effects of tiron on mitochondrial function and osteoblastic differentiation in human periosteum-derived cells (hPDCs). Tiron increased mitochondrial activity and decreased senescence-associated β-galactosidase activity in hPDCs; however, it had a detrimental effect on osteoblastic differentiation by reducing alkaline phosphatase (ALP) activity and alizarin red-positive mineralization, regardless of H2O2 treatment. Osteoblast-differentiating hPDCs displayed increased ROS production compared with non-differentiating hPDCs, and treatment with tiron reduced ROS production in the differentiating cells. Antioxidants decreased the rates of oxygen consumption and ATP production, which are increased in hPDCs during osteoblastic differentiation. In addition, treatment with tiron reduced the levels of most mitochondrial proteins, which are increased in hPDCs during culture in osteogenic induction medium. These results suggest that tiron exerts negative effects on the osteoblastic differentiation of hPDCs by causing mitochondrial dysfunction. 相似文献
68.
Congxia Hu Jun Wu Pengxiao Li Yabin Zhang Yonglin Peng Ruiqi Liu Wenfei Du Yani Kang Jielin Sun Ji Wu Zhifeng Shao Xiaodong Zhao 《International journal of molecular sciences》2022,23(22)
Chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-seq) can profile genome-wide epigenetic marks associated with regulatory genomic elements. However, conventional ChIP-seq is challenging when examining limited numbers of cells. Here, we developed a new technique by supplementing carrier materials of both chemically modified mimics with epigenetic marks and dUTP-containing DNA fragments during conventional ChIP procedures (hereafter referred to as 2cChIP-seq), thus dramatically improving immunoprecipitation efficiency and reducing DNA loss of low-input ChIP-seq samples. Using this strategy, we generated high-quality epigenomic profiles of histone modifications or DNA methylation in 10–1000 cells. By introducing Tn5 transposase-assisted fragmentation, 2cChIP-seq reliably captured genomic regions with histone modification at the single-cell level in about 100 cells. Moreover, we characterized the methylome of 100 differentiated female germline stem cells (FGSCs) and observed a particular DNA methylation signature potentially involved in the differentiation of mouse germline stem cells. Hence, we provided a reliable and robust epigenomic profiling approach for small cell numbers and single cells. 相似文献
69.
Xiaolei Lin Tianke Yang Xin Liu Fan Fan Xiyue Zhou Hongzhe Li Yi Luo 《International journal of molecular sciences》2022,23(22)
Congenital cataract is the leading cause of blindness among children worldwide. Patients with posterior subcapsular congenital cataract (PSC) in the central visual axis can result in worsening vision and stimulus deprivation amblyopia. However, the pathogenesis of PSC remains unclear. This study aims to explore the functional regulation and mechanism of HTRA1 in human lens epithelial cells (HLECs). HTRA1 was significantly downregulated in the lens capsules of children with PSC compared to normal controls. HTRA1 is a suppression factor of transforming growth factor-β (TGF-β) signalling pathway, which plays a key role in cataract formation. The results showed that the TGF-β/Smad signalling pathway was activated in the lens tissue of PSC. The effect of HTRA1 on cell proliferation, migration and apoptosis was measured in HLECs. In primary HLECs, the downregulation of HTRA1 can promote the proliferation and migration of HLECs by activating the TGF-β/Smad signalling pathway and can significantly upregulate the TGF-β/Smad downstream target genes FN1 and α-SMA. HTRA1 was also knocked out in the eyes of C57BL/6J mice via adeno-associated virus-mediated RNA interference. The results showed that HTRA1 knockout can significantly upregulate p-Smad2/3 and activate the TGF-β/Smad signalling pathway, resulting in abnormal proliferation and irregular arrangement of lens epithelial cells and leading to the occurrence of subcapsular cataract. To conclude, HTRA1 was significantly downregulated in children with PSC, and the downregulation of HTRA1 enhanced the proliferation and migration of HLECs by activating the TGF-β/Smad signalling pathway, which led to the occurrence of PSC. 相似文献
70.
Ajjima Chansaenroj Chatvadee Kornsuthisopon Sittiruk Roytrakul Suphalak Phothichailert Sunisa Rochanavibhata Benjamin P. J. Fournier Supreda Suphanantachat Srithanyarat Nunthawan Nowwarote Thanaphum Osathanon 《International journal of molecular sciences》2022,23(22)
The indirect immobilisation of Jagged-1 (Jagged-1) promoted osteogenic differentiation of human dental pulp cells (hDPs). Furthermore, the analysis of the Reactome pathway of RNA sequencing data indicates the upregulated genes involved with the extracellular matrix (ECM). Hence, our objective was to investigate the effects of Jagged-1 on proteomic profiles of human dental pulp stem cells (hDPSC). hDPSCs were cultured on the surface coated with human IgG Fc fragment (hFc) and the surface coated with rhJagged1/Fc recombinant protein-coated surface. Cells were differentiated to the osteogenic lineage using an osteogenic differentiation medium (OM) for 14 days, and cells cultured in a growth medium were used as a control. The protein component of the cultured cells was extracted into the cytosol, membrane, nucleus, and cytoskeletal compartment. Subsequently, the proteomic analysis was performed using liquid chromatography–tandem mass spectrometry (LC-MS). Metascape gene list analysis reported that Jagged-1 stimulated the expression of the membrane trafficking protein (DOP1B), which can indirectly improve osteogenic differentiation. hDPSCs cultured on Jagged-1 surface under OM condition expressed COL27A1, MXRA5, COL7A1, and MMP16, which played an important role in osteogenic differentiation. Furthermore, common matrisome proteins of all cellular components were related to osteogenesis/osteogenic differentiation. Additionally, the gene ontology categorised by the biological process of cytosol, membrane, and cytoskeleton compartments was associated with the biomineralisation process. The gene ontology of different culture conditions in each cellular component showed several unique gene ontologies. Remarkably, the Jagged-1_OM culture condition showed the biological process related to odontogenesis in the membrane compartment. In conclusion, the Jagged-1 induces osteogenic differentiation could, mainly through the regulation of protein in the membrane compartment. 相似文献