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51.
准噶尔盆地白垩系低阻油气藏测井系列选择 总被引:5,自引:3,他引:2
准噶尔盆地白晋系油气藏具有孔隙度,渗透率高,地层水矿化度,压力系数和电阻率低等低电阻率油气藏的基本特征,对典型储集层测井资料的分析和电阻率测井响应理论模拟表明,白晋系低阻油气藏钻井液侵入主要发生在打开油气层的初期,并以钻井液的“喷失”侵入为主,及时测井对于改善油气,水层的识别效果不明显,感应测井与侧向测井的对比测量结果表明,油气层,水层的深,浅感应测井电阻率差异特征显著,油气层感应测井电阻率高于侧向测井电阻率,水层感应测井电阻率则小于侧向测井电阻率,在快速识别白晋系低阻油气层和水层的效果上,感应测井明显优于侧向测井,根据新疆油田公司测井技术装备现状,分别制订并实施了低阻油气藏预探井,评价井和生产井三种测井系列,提高了勘探开发效果,地质效果明显。 相似文献
52.
Cheng Du Li Chen Haijun Zhang Zhongchao Wang Wenchao Liu Xiaodong Xie Manjiang Xie 《International journal of molecular sciences》2014,15(11):20706-20722
Increasing evidence suggests that caveolin-1 and large conductance Ca2+-activated potassium (BKCa) channels are implicated in the carcinogenesis processes, including cell proliferation and invasion. These two proteins have been proven to interact with each other in vascular endothelial and smooth muscle cells and modulate vascular contractility. In this study, we investigated the probable interaction between caveolin-1 and BKCa in MCF-7 breast cancer cells. We identified that caveolin-1 and BKCa were co-localized and could be reciprocally co-immunoprecipitated in human breast cancer MCF-7 cells. siRNA mediated caveolin-1 knockdown resulted in activation and increased surface expression of BKCa channel, and subsequently promoted the proliferation and invasiveness of breast cancer cells. These effects were attenuated in the presence of BKCa-siRNA. Conversely, up-regulated caveolin-1 suppressed function and surface expression of BKCa channel and exerted negative effects on breast cancer cell proliferation and invasion. Similarly, these opposing effects were abrogated by BKCa up-regulation. Collectively, our findings suggest that BKCa is a critical target for suppression by caveolin-1 in suppressing proliferation and invasion of breast cancer cells. The functional complex of caveolin-1 and BKCa in the membrane microdomain may be served as a potential therapeutic target in breast cancer. 相似文献
53.
Hui Xia Shengjie Sun Bo Wang Tao Wang Chaoyang Liang Guo Li Chongbiao Huang Daliang Qi Xiangyang Chu 《International journal of molecular sciences》2014,15(7):11973-11983
MicroRNAs (miRNAs) have essential roles in carcinogenesis and tumor progression. Here, we investigated the roles and mechanisms of miR-143 in non-small cell lung cancer (NSCLC). miR-143 was significantly decreased in NSCLC tissues and cell lines. Overexpression of miR-143 suppressed NSCLC cell proliferation, induced apoptosis, and inhibited migration and invasion in vitro. Integrated analysis identified LIM domain kinase 1 (Limk1) as a direct and functional target of miR-143. Overexpression of Limk1 attenuated the tumor suppressive effects of miR-143 in NSCLC cells. Moreover, miR-143 was inversely correlated with Limk1 expression in NSCLC tissues. Together, our results highlight the significance of miR-143 and Limk1 in the development and progression of NSCLC. 相似文献
54.
Yuan Wang Haifeng Qiu Weixu Hu Shaoru Li Jinjin Yu 《International journal of molecular sciences》2014,15(3):4780-4794
The platelet-derived growth factor-D (PDGF-D) was demonstrated to be able to promote tumor growth and invasion in human malignancies. However, little is known about its roles in endometrial cancer. In the present study, we investigated the expression and functions of PDGF-D in human endometrial cancer. Alterations of PDGF-D mRNA and protein were determined by real time PCR, western blot and immunohistochemical staining. Up-regulation of PDGF-D was achieved by stably transfecting the pcDNA3-PDGF-D plasmids into ECC-1 cells; and knockdown of PDGF-D was achieved by transient transfection with siRNA-PDGF-D into Ishikawa cells. The MTT assay, colony formation assay and Transwell assay were used to detect the effects of PDGF-D on cellular proliferation and invasion. The xenograft assay was used to investigate the functions of PDGF-D in vivo. Compared to normal endometrium, more than 50% cancer samples showed over-expression of PDGF-D (p < 0.001), and high level of PDGF-D was correlated with late stage (p = 0.003), deep myometrium invasion (p < 0.001) and lympha vascular space invasion (p = 0.006). In vitro, over-expressing PDGF-D in ECC-1 cells significantly accelerated tumor growth and promoted cellular invasion by increasing the level of MMP2 and MMP9; while silencing PDGF-D in Ishikawa cells impaired cell proliferation and inhibited the invasion, through suppressing the expression of MMP2 and MMP9. Moreover, we also demonstrated that over-expressed PDGF-D could induce EMT and knockdown of PDGF-D blocked the EMT transition. Consistently, in xenografts assay, PDGF-D over-expression significantly promoted tumor growth and tumor weights. We demonstrated that PDGF-D was commonly over-expressed in endometrial cancer, which was associated with late stage deep myometrium invasion and lympha vascular space invasion. Both in vitro and in vivo experiments showed PDGF-D could promote tumor growth and invasion through up-regulating MMP2/9 and inducing EMT. Thus, we propose targeting PDGF-D to be a potent strategy for endometrial cancer treatment. 相似文献
55.
56.
火成岩岩相决定了火成岩体中原生孔隙的发育规律,影响着后期的构造形变、断裂破碎对火成岩储层的改善程度,是影响储层性质的基本因素之一。通过研究明确了济阳坳陷火成岩不同岩相的识别特征,建立了岩相分布模式,包括侵入相及相关变质相模式、火山碎屑锥相模式及溢流玄武岩火山相相模式三种类型,为火成岩储层的综合评价奠定基础。 相似文献
57.
证券信息网络系统安全解决方案 总被引:1,自引:0,他引:1
描述了证券信息系统的特点 ,从系统安全的角度 ,分析了证券网络系统存在的安全隐患 ,提出了网络设计必须遵循的原则和应对措施。 相似文献
58.
We assessed the importance of flow regime to the success of native and non‐native fish species by analysing winter/spring seining data collected from 1987 to 1997 on the resident fish communities of the lower Tuolumne River, California. The data were analysed using regression models to predict the percentage of non‐native fish at a site. The regression models included various combinations of the variables longitudinal location of the site, mean April/May stream discharge in the year of sampling, and mean April/May stream discharge in the previous year. Comparison of the models indicated that the best model included longitudinal location and stream discharge in the previous year. This model is consistent with the hypothesis that flow in the previous year differentially affects reproductive success of native and non‐native species and thus the resulting community sampled in the following winter/spring. A detrended correspondence analysis of percentage abundance species data identified a co‐occurring group of native species and a co‐occurring group of non‐native species with the non‐native red shiner (Cyprinella lutrensis) grouping separately. The differing reproductive strategies of the species were consistent with the hypothesis concerning spawning success. Our results indicate that flow regime is an important determinant of the reproductive success of native and non‐native fish species in regulated rivers. Manipulations of flow regime are a potentially powerful tool for managing native fish species, but should be considered in combination with other restoration efforts and in the context of ecosystem restoration. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
59.
水平井中双侧向测井的侵入校正 总被引:2,自引:0,他引:2
由于重力作用,水平井的侵入带已不再是对称于井轴的圆柱体,将侵入带效为圆柱体,仪器位于偏心轴上来逼近实际模型。以偏心点电流泊的电位格林函数为基础,求解测井响应并绘制侵入校正图版,由此可求得原状地层电阻率和等效侵入半径。 相似文献
60.
淡水钻井液侵入对双感应和双侧向测井响应的影响 总被引:2,自引:0,他引:2
钻井液侵入储集层将导致储集层含水饱和度、地层水矿化度、地层电阻率等的径向变化。由于双感应和双侧向测井测量原理的不同,地层电阻率的径向变化对其测井响应特征影响也不同。实测资料统计和数值模拟计算结果均证实,水层双侧向测井受淡水钻井液增阻侵入影响较大,钻井液愈淡,水层的侧向测井值愈高;而在好油层双感应测井受淡水钻井液减阻侵入影响较大。针对目前勘探较多的低电阻率油层,结合淡水钻井液侵入对双感应和双侧向测井响应特征影响的差异,建立了应用双感应测井或双感应、双侧向测井联合的油、水层识别方法,并在此基础上建立了油层含油饱和度的定量评价方法,提高了低电阻率油层的测井识别评价能力。图7参19 相似文献