全文获取类型
收费全文 | 147396篇 |
免费 | 21035篇 |
国内免费 | 4612篇 |
专业分类
电工技术 | 6896篇 |
技术理论 | 10篇 |
综合类 | 6878篇 |
化学工业 | 34679篇 |
金属工艺 | 6434篇 |
机械仪表 | 7757篇 |
建筑科学 | 10746篇 |
矿业工程 | 2927篇 |
能源动力 | 3924篇 |
轻工业 | 13773篇 |
水利工程 | 2411篇 |
石油天然气 | 5694篇 |
武器工业 | 853篇 |
无线电 | 19653篇 |
一般工业技术 | 23862篇 |
冶金工业 | 6229篇 |
原子能技术 | 1260篇 |
自动化技术 | 19057篇 |
出版年
2024年 | 426篇 |
2023年 | 1645篇 |
2022年 | 3080篇 |
2021年 | 4404篇 |
2020年 | 4430篇 |
2019年 | 5585篇 |
2018年 | 5794篇 |
2017年 | 6545篇 |
2016年 | 6744篇 |
2015年 | 7830篇 |
2014年 | 9013篇 |
2013年 | 11302篇 |
2012年 | 9644篇 |
2011年 | 9650篇 |
2010年 | 9186篇 |
2009年 | 8828篇 |
2008年 | 8211篇 |
2007年 | 7897篇 |
2006年 | 7733篇 |
2005年 | 6710篇 |
2004年 | 4977篇 |
2003年 | 4483篇 |
2002年 | 4206篇 |
2001年 | 3735篇 |
2000年 | 3796篇 |
1999年 | 3327篇 |
1998年 | 2605篇 |
1997年 | 2064篇 |
1996年 | 1884篇 |
1995年 | 1564篇 |
1994年 | 1310篇 |
1993年 | 933篇 |
1992年 | 714篇 |
1991年 | 590篇 |
1990年 | 451篇 |
1989年 | 391篇 |
1988年 | 339篇 |
1987年 | 190篇 |
1986年 | 181篇 |
1985年 | 117篇 |
1984年 | 102篇 |
1983年 | 70篇 |
1982年 | 65篇 |
1981年 | 58篇 |
1980年 | 45篇 |
1979年 | 35篇 |
1978年 | 14篇 |
1977年 | 36篇 |
1976年 | 19篇 |
1975年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
Nazir Kizzie‐Hayford Doris Jaros Yvonne Schneider Harald Rohm 《International Journal of Food Science & Technology》2015,50(2):381-388
A standard method for the extraction of tiger nut milk has been introduced. It has been shown that, although milling duration improves the yield of tiger nut milk solids and its nutrient composition, there is a quantifiable loss of nutrient in the pressing residue during milk extraction. Milling duration improved the colloidal stability of the milk against creaming during 16 h of storage. A higher milling intensity resulted in the aggregation of biological polymers which resulted in colloidal destabilisation. Milling improved the lightness and stability and reduced browning rate of the tiger nut milk during storage. This report is important for the production of tiger nut milk of consistent and comparable characteristics. Milling has been introduced as a processing method for the qualitative and quantitative modulation of the properties of tiger nut milk. It is recommended to develop further strategies to improve the colloidal stability of tiger nut milk as a beverage. 相似文献
13.
14.
针对区域地面沉降监测点数量有限、分布不均的情况,一般采用空间插值的手段建立表面拟合模型来解决。基于分形插值,采用随机选择迭代函数的思想对传统的趋势面拟合法作出改进,改进后拟合优度系数提高0.03,达到0.995,且改进前后的拟合结果符合显著性检验的要求。实验结果表明:改进前后趋势面拟合法拟合结果满足地面沉降监测的精度要求,改进后方法的拟合优度更高,对现实地面沉降量变化的描绘更加真实,可为沉降灾害评价工作提供更准确的依据。 相似文献
15.
16.
17.
In vivo Kinetic Biodistribution of Nano‐Sized Outer Membrane Vesicles Derived from Bacteria 下载免费PDF全文
Su Chul Jang Sae Rom Kim Yae Jin Yoon Kyong‐Su Park Ji Hyun Kim Jaewook Lee Oh Youn Kim Eun‐Jeong Choi Dae‐Kyum Kim Dong‐Sic Choi Yoon‐Keun Kim Jaesung Park Dolores Di Vizio Yong Song Gho 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(4):456-461
Evaluation of kinetic distribution and behaviors of nanoparticles in vivo provides crucial clues into their roles in living organisms. Extracellular vesicles are evolutionary conserved nanoparticles, known to play important biological functions in intercellular, inter‐species, and inter‐kingdom communication. In this study, the first kinetic analysis of the biodistribution of outer membrane vesicles (OMVs)—bacterial extracellular vesicles—with immune‐modulatory functions is performed. OMVs, injected intraperitoneally, spread to the whole mouse body and accumulate in the liver, lung, spleen, and kidney within 3 h of administration. As an early systemic inflammation response, increased levels of TNF‐α and IL‐6 are observed in serum and bronchoalveolar lavage fluid. In addition, the number of leukocytes and platelets in the blood is decreased. OMVs and cytokine concentrations, as well as body temperature are gradually decreased 6 h after OMV injection, in concomitance with the formation of eye exudates, and of an increase in ICAM‐1 levels in the lung. Following OMV elimination, most of the inflammatory signs are reverted, 12 h post‐injection. However, leukocytes in bronchoalveolar lavage fluid are increased as a late reaction. Taken together, these results suggest that OMVs are effective mediators of long distance communication in vivo. 相似文献
18.
19.
Yao‐Min Hung Neng‐Chyan Huang Jyh‐Seng Wang Shue‐Ren Wann 《Hemodialysis international. International Symposium on Home Hemodialysis》2015,19(2):344-346
Cases of isolated hepatic tuberculosis (TB) are rare. The diagnosis is often delayed or missed because of nonspecific symptoms and laboratory findings. Besides, the disease is extremely rare even in a country where TB is an alarming public health problem. This report demonstrates the difficulty in correctly diagnosing local hepatic TB. We report the case of a 62‐year‐old male patient with end‐stage renal disease treated with hemodialysis, who developed 2 months of abdominal distension and general anorexia, with hyperechoic hepatic lesions on ultrasound. Computed tomography suspected multiple liver tumors. The liver biopsy finally led to the diagnosis of TB of the liver without other involvements. We conclude that isolated hepatic TB is one of the rare forms of extrapulmonary TB in dialysis patients. A greater awareness of this rare clinical entity may prevent needless surgical interventions. 相似文献
20.
Cerebral microbleeds and cognitive decline in a hemodialysis patient: Case report and review of literature 下载免费PDF全文
Lin Li Mark Fisher Wei‐Ling Lau Hamid Moradi Alexander Cheung Gaby Thai Jason Handwerker Kamyar Kalantar‐Zadeh 《Hemodialysis international. International Symposium on Home Hemodialysis》2015,19(3):E1-E7
Cerebral microbleeds (CMBs) are small hemosiderin deposits indicative of prior cerebral microscopic hemorrhage and previously thought to be clinically silent. Recent population‐based cross‐sectional studies and prospective longitudinal cohort studies have revealed association between CMB and cognitive dysfunction. In the general population, CMBs are associated with age, hypertension, and cerebral amyloid angiopathy. In the chronic kidney disease (CKD) population, diminished estimated glomerular filtration rate has been found to be an independent risk factor for CMB, raising the possibility that a uremic milieu may predispose to microbleeds. In the end‐stage renal disease (ESRD) population on hemodialysis, the incidence of microbleeds is significantly higher compared with a control group without history of CKD or stroke. We present an ESRD patient on chronic hemodialysis with a history of gradual cognitive decline and progressive CMBs. Through this case and literature review, we illustrate the need to develop detection and prediction models to treat this frequent development in ESRD patients. 相似文献