全文获取类型
收费全文 | 318篇 |
免费 | 6篇 |
专业分类
电工技术 | 4篇 |
化学工业 | 45篇 |
金属工艺 | 17篇 |
机械仪表 | 1篇 |
建筑科学 | 27篇 |
矿业工程 | 1篇 |
能源动力 | 7篇 |
轻工业 | 28篇 |
水利工程 | 1篇 |
无线电 | 52篇 |
一般工业技术 | 31篇 |
冶金工业 | 38篇 |
自动化技术 | 72篇 |
出版年
2023年 | 4篇 |
2022年 | 3篇 |
2021年 | 12篇 |
2020年 | 6篇 |
2019年 | 9篇 |
2018年 | 15篇 |
2017年 | 5篇 |
2016年 | 10篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 25篇 |
2012年 | 13篇 |
2011年 | 14篇 |
2010年 | 15篇 |
2009年 | 17篇 |
2008年 | 20篇 |
2007年 | 13篇 |
2006年 | 14篇 |
2005年 | 10篇 |
2004年 | 6篇 |
2003年 | 4篇 |
2002年 | 9篇 |
2001年 | 8篇 |
2000年 | 1篇 |
1999年 | 8篇 |
1998年 | 10篇 |
1997年 | 7篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 8篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 4篇 |
1971年 | 1篇 |
排序方式: 共有324条查询结果,搜索用时 9 毫秒
71.
P Radermacher R Buhl B Santak M Klein HW Kniemeyer H Becker J Tarnow 《Canadian Metallurgical Quarterly》1995,21(5):414-421
OBJECTIVE: To investigate whether infusing prostacyclin (PGI2) in patients with septic shock improves splanchnic oxygenation as assessed by gastric intramucosal pH (pHi). DESIGN: Interventional clinical study. SETTING: Surgical ICU in a university hospital. PATIENTS: 16 consecutive patients with septic shock according to the criteria of the ACCP/SCCM consensus conference all requiring norepinephrine to maintain arterial blood pressure. INTERVENTIONS: All patients received PGI2 (10 ng/kg x min) after no further increase in oxygen delivery could be obtained by volume expansion, red cell transfusion and dobutamine infusion. The results were compared with those before and after conventional resuscitation. The patients received continuous PGI2 infusion for 33-32 days. MEASUREMENTS AND RESULTS: O2 uptake was measured directly in the respiratory gases, pHi was determined by tonometry. Baseline O2 delivery, O2 uptake and pHi were 466 +/- 122 ml/min.m2, 158 +/- 38 ml/min.m2, and 7.29 +/- 0.09, respectively. While O2 uptake remained unchanged, infusing PGI2 increased O2 delivery (from 610 +/- 140 to 682 +/- 155 ml/min.m2, p < 0.01) and pHi (from 7.32 +/- 0.09 to 7.38 +/- 0.08, p < 0.001) beyond the values obtained by conventional resuscitation. While 9 of 11 patients with final pHi > 7.35 survived, all patients with final pHi < 7.35 died (p < 0.01). CONCLUSIONS: Infusing PGI2 in patients with septic shock increases pHi probably by enhancing blood flow to the splanchnic bed and thereby improves splanchnic oxygenation even when conventional resuscitation goals have been achieved. 相似文献
72.
Hinshaw Stephen P.; Simmel Cassandra; Heller Tracy L. 《Canadian Metallurgical Quarterly》1995,7(2):209
Given the high risk for delinquency of children with attention-deficit hyperactivity disorder (ADHD), their display of covert or clandestine antisocial behavior is important developmentally and theoretically. In a laboratory probe of the temptation to (a) steal small amounts of money and desired objects, (b) destroy property, and (c) use an answer key to cheat on a worksheet, counts of these covert behaviors were reliably made. Laboratory property destruction was highly correlated with parallel naturalistic behaviors. Stealing and property destruction (but not cheating) formed a factor that was distinct from overt physical and verbal aggression. These covert indexes clearly distinguished ADHD from comparison samples as well as high- from low-aggressive ADHD subgroups; they showed external validity with maternal reports, global staff ratings, and child self-reports of similar constructs. The authors discuss psychometric and ethical issues in the assessment of covert antisocial behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
Larval flannelmouth sucker (Catostomus latipinnis) were exposed to arsenate, boron, copper, molybdenum, selenate, selenite, uranium, vanadium, and zinc singly, and to five mixtures of five to nine inorganics. The exposures were conducted in reconstituted water representative of the San Juan River near Shiprock, New Mexico. The mixtures simulated environmental ratios reported for sites along the San Juan River (San Juan River backwater, Fruitland marsh, Hogback East Drain, Mancos River, and McElmo Creek). The rank order of the individual inorganics, from most to least toxic, was: copper > zinc > vanadium > selenite > selenate > arsenate > uranium > boron > molybdenum. All five mixtures exhibited additive toxicity to flannelmouth sucker. In a limited number of tests, 44-day-old and 13-day-old larvae exhibited no difference in sensitivity to three mixtures. Copper was the major toxic component in four mixtures (San Juan backwater, Hogback East Drain, Mancos River, and McElmo Creek), whereas zinc was the major toxic component in the Fruitland marsh mixture, which did not contain copper. The Hogback East Drain was the most toxic mixture tested. Comparison of 96-h LC50 values with reported environmental water concentrations from the San Juan River revealed low hazard ratios for arsenic, boron, molybdenum, selenate, selenite, uranium, and vanadium, moderate hazard ratios for zinc and the Fruitland marsh mixture, and high hazard ratios for copper at three sites and four environmental mixtures representing a San Juan backwater, Hogback East Drain, Mancos River, and McElmo Creek. The high hazard ratios suggest that inorganic contaminants could adversely affect larval flannelmouth sucker in the San Juan River at four sites receiving elevated inorganics. 相似文献
74.
Differentiating Antiproliferative and Chemopreventive Modes of Activity for Electron‐Deficient Aryl Isothiocyanates against Human MCF‐7 Cells 下载免费PDF全文
75.
P. N. Buhl 《The International journal of environmental studies》2020,77(3):510-522
ABSTRACT The following five species are described as new to science: Inostemma muelleri sp. n., Metaclisis iranica sp. n., Platygaster curvistriata sp. n., Platygaster nepalica sp. n. and Prosynopeas antoni sp. n. The type material of Metaclisis ocalea (Walker) is described, and M. ocalea (Walker) and M. montagnei Maneval are synonymised with M. areolata (Haliday). 相似文献
76.
A method and a device are proposed that allow measurement of the polarization mode dispersion (PMD) in a transmission line without data traffic interruption. The PMD vector information is extracted from the optical data signal spectrum. The method is experimentally verified by measuring of first-order PMD 相似文献
77.
Jeff S. Volek Stephen D. Phinney Cassandra E. Forsythe Erin E. Quann Richard J. Wood Michael J. Puglisi William J. Kraemer Doug M. Bibus Maria Luz Fernandez Richard D. Feinman 《Lipids》2009,44(4):297-309
We recently proposed that the biological markers improved by carbohydrate restriction were precisely those that define the
metabolic syndrome (MetS), and that the common thread was regulation of insulin as a control element. We specifically tested
the idea with a 12-week study comparing two hypocaloric diets (~1,500 kcal): a carbohydrate-restricted diet (CRD) (%carbohydrate:fat:protein = 12:59:28)
and a low-fat diet (LFD) (56:24:20) in 40 subjects with atherogenic dyslipidemia. Both interventions led to improvements in
several metabolic markers, but subjects following the CRD had consistently reduced glucose (−12%) and insulin (−50%) concentrations,
insulin sensitivity (−55%), weight loss (−10%), decreased adiposity (−14%), and more favorable triacylglycerol (TAG) (−51%),
HDL-C (13%) and total cholesterol/HDL-C ratio (−14%) responses. In addition to these markers for MetS, the CRD subjects showed
more favorable responses to alternative indicators of cardiovascular risk: postprandial lipemia (−47%), the Apo B/Apo A-1
ratio (−16%), and LDL particle distribution. Despite a threefold higher intake of dietary saturated fat during the CRD, saturated
fatty acids in TAG and cholesteryl ester were significantly decreased, as was palmitoleic acid (16:1n-7), an endogenous marker
of lipogenesis, compared to subjects consuming the LFD. Serum retinol binding protein 4 has been linked to insulin-resistant
states, and only the CRD decreased this marker (−20%). The findings provide support for unifying the disparate markers of
MetS and for the proposed intimate connection with dietary carbohydrate. The results support the use of dietary carbohydrate
restriction as an effective approach to improve features of MetS and cardiovascular risk.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
78.
Manny Randhawa Isabelle Gartner Cassandra Becker James Student Minghui Chai Anja Mueller 《应用聚合物科学杂志》2007,106(5):3321-3326
Imprinting polymerization is used to make resins with a high capacity for cadmium ions for wastewater treatment. A random copolymer of methacrylate and methacrylamide was found to be most effective, especially when the porosity of the resin is increased. Complete removal for up to 80 ppm of cadmium with only 50 mg of resin was demonstrated with the imprinted resins, but not the nonimprinted reference samples. This shows that imprinting polymerization improves the capacity of the resin in the uptake of cadmium ions. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
79.
80.
To support a value-based management and to satisfy regulatory transparency requirements and legal reporting obligations, corporations require a corporate-wide consistent database with return and risk information. Despite existing technical integration approaches, such as data warehouse or OLAP solutions, the development of corporate-wide consistent return and risk databases is so far impossible, as adequate financial methods and performance measurement systems are lacking. Integrated Enterprise Balancing enables corporations of all industries to control their business activities with corporate-wide consistent return and risk measures. The presented performance measurement system enables corporations to additively connect return and risk measures on arbitrary aggregation levels and to perform such an aggregation also within multiple dimensions. Hence, it is a conceptual solution for the development of integrated return and risk databases. 相似文献