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51.
利用昆虫病毒防治害虫是生物防治的一种有效方法。主要针对昆虫病毒的作用机制、后效作用以及重组昆虫病毒和昆虫病毒感染增效物质等方面进行了阐述。 相似文献
52.
J. G. Mantovani D. P. Allison R. J. Warmack T. L. Ferrell J. R. Ford R. E. Manos J. R. Thompson B. B. Reddick K. Bruce Jacobson 《Journal of microscopy》1990,158(1):109-116
We present scanning tunnelling microscope (STM) images of untreated tobacco mosaic virus (TMV) deposited on thermally evaporated and on sputter-coated palladium/gold 40:60 (Pd/Au) substrates, and imaged under ordinary atmospheric conditions. The TMV imaged on both evaporated and sputter-coated substrates was consistently several times wider than the known diameter of the virus. TMV on evaporated Pd/Au became overcoated with Pd/Au material during sample preparation and appeared elevated in STM images, whereas TMV on sputter-coated Pd/Au appeared as depressions. When naked TMV were intentionally overcoated with Pd/Au, the STM images were found to be similar to those for TMV on evaporated Pd/Au. 相似文献
53.
冬虫夏草菌丝体水提物的抗新城疫病毒作用 总被引:1,自引:0,他引:1
通过低温水浸提取方法,获取冬虫夏草菌丝体水提物。采用MTT的方法和观察细胞病变(CPE)的方法分别研究了水提物毒性和抗病毒作用。结果显示水提物浓度≤0.5mg/mL时,对Vero细胞无毒性,0.5mg/mL水提物与新城疫病毒作用,或预处理Vero细胞,均能抑制新城疫病毒在细胞上病变的形成。提示水提物具有直接抗新城疫病毒和预防新城疫病毒感染的作用。 相似文献
54.
描述了高能所反垃圾邮件和防病毒的方案和策略,并介绍了相关经验。 相似文献
55.
证据显示,传统中药(TCM)加核苷类似物(NA)抗乙型肝炎病毒(HBV)感染治疗可能不仅压制患者血清HBVDNA水平,而且还能激活患者的特殊免疫功能直接清除HBV而几乎不损伤患者的肝细胞。提出一个具有5个变量的微分方程模型来描述TCM+NA抗HBV感染治疗动力学。证明当新模型的基本病毒复制数R0<1时,病毒清除平衡点全局吸引。这意指如果抗病毒感染治疗使得患者的R0<1,则即使患者的血清HBVDNA水平非常高也将最终痊愈。作为应用,运用新模型模拟TCM+NA抗HBV感染个性化组合治疗的动力学。数值模拟和分析说明TCM+NA组合治疗能够激活病人细胞因子介导的非细胞毒性HBV清除能力。 相似文献
56.
57.
M. Thomä A. Gester G. Wagner B. Straß B. Wolter S. Benfer D. K. Gowda W. Fürbeth 《Materialwissenschaft und Werkstofftechnik》2019,50(8):893-912
Friction stir welding as a solid‐state joining method with its comparatively low process temperatures is suitable for joining dissimilar materials like aluminum/magnesium or aluminum/steel. Such hybrid joints are of great interest regarding lightweight efforts in different industrial fields like the transportation area. The present work investigates the influence of additionally transmitted power ultrasound during the friction stir welding on the joint properties of EN AC‐48000/AZ91 and EN AW‐6061/DP600. Therefore, conventional friction stir welding was continuously compared to ultrasound enhanced friction stir welding. Light microscopic analysis and nondestructive testing of the joints using x‐ray and high frequency ultrasound show different morphologies of the nugget for the aluminum/magnesium joints as well as differences in the amount and size of steel particles in the nugget of aluminum/steel joints. Scanning electron microcopy proves differences in the thickness of continuous intermetallic layers for the aluminum/steel joints realized with and without power ultrasound. Regarding the tensile strength of the joints the power ultrasound leads to increased joint strengths for EN AC‐48000/AZ91 joints compared to a decrease for EN AW‐6061/DP600 joints. Corrosion investigations show an influence of the ultrasound power on the corrosion properties of EN AC‐48000/AZ91 joints which is attributed to a changed aluminum content in the nugget region. Because of the great potential difference between the magnesium and the nugget phase the transitional area exhibits strong galvanic corrosion. For EN AW‐6061/DP600 joints an increased corrosion caused by galvanic effects is not expected as the potentials of the EN AW‐6061 aluminum alloy and DP600 steel are very similar. 相似文献
58.
59.
Heng-Wei Lee Cheng-Yao Yang Ming-Chang Lee Shih-Ping Chen Hui-Wen Chang Ivan-Chen Cheng 《International journal of molecular sciences》2022,23(15)
The serum neutralization (SN) test has been regarded as the “gold standard” for seroconversion following foot-and-mouth disease virus (FMDV) vaccination, although a high-level biosafety laboratory is necessary. ELISA is one alternative, and its format is constantly being improved. For instance, standard polyclonal antisera have been replaced by monoclonal antibodies (MAbs) for catching and detecting antibodies, and inactive viruses have been replaced by virus-like particles (VLPs). To the best of current knowledge, however, no researchers have evaluated the performances of different MAbs as tracers. In previous studies, we successfully identified site 1 and site 2 MAbs Q10E and P11A. In this study, following the established screening platform, the VLPs of putative escape mutants from sites 1 to 5 were expressed and used to demonstrate that S11B is a site 3 MAb. Additionally, the vulnerability of VLPs prompted us to assess another diagnostic antigen: unprocessed polyprotein P1. Therefore, we established and evaluated the performance of blocking ELISA (bELISA) systems based on VLPs and P1, pairing them with Q10E, P11A, S11B, and the non-neutralizing TSG MAb as tracers. The results indicated that the VLP paired with S11B demonstrated the highest correlation with the SN titers (R2 = 0.8071, n = 63). Excluding weakly positive serum samples (SN = 16–32, n = 14), the sensitivity and specificity were 95.65% and 96.15% (kappa = 0.92), respectively. Additionally, the P1 pairing with Q10E also demonstrated a high correlation (R2 = 0.768). We also discovered that these four antibodies had steric effects on one another to varying degrees, despite recognizing distinct antigenic sites. This finding indicated that MAbs as tracers could not accurately detect specific antibodies, possibly because MAbs are bulky compared to a protomeric unit. However, our results still provide convincing support for the application of two pairs of bELISA systems: VLP:S11B-HRP and P1:Q10E-HRP. 相似文献
60.
Xiaoyu Li Masahiko Ito Haruyo Aoyagi Asako Murayama Hideki Aizaki Masayoshi Fukasawa Takanobu Kato Takaji Wakita Tetsuro Suzuki 《International journal of molecular sciences》2022,23(15)
In microbiological research, it is important to understand the time course of each step in a pathogen’s lifecycle and changes in the host cell environment induced by infection. This study is the first to develop a real-time monitoring system that kinetically detects luminescence reporter activity over time without sampling cells or culture supernatants for analyzing the virus replication. Subgenomic replicon experiments with hepatitis C virus (HCV) showed that transient translation and genome replication can be detected separately, with the first peak of translation observed at 3–4 h and replication beginning around 20 h after viral RNA introduction into cells. From the bioluminescence data set measured every 30 min (48 measurements per day), the initial rates of translation and replication were calculated, and their capacity levels were expressed as the sums of the measured signals in each process, which correspond to the areas on the kinetics graphs. The comparison of various HuH-7-derived cell lines showed that the bioluminescence profile differs among cell lines, suggesting that both translation and replication capacities potentially influence differences in HCV susceptibility. The effects of RNA mutations within the 5′ UTR of the replicon on viral translation and replication were further analyzed in the system developed, confirming that mutations to the miR-122 binding sites primarily reduce replication activity rather than translation. The newly developed real-time monitoring system should be applied to the studies of various viruses and contribute to the analysis of transitions and progression of each process of their life cycle. 相似文献