全文获取类型
收费全文 | 1000篇 |
免费 | 29篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 10篇 |
综合类 | 2篇 |
化学工业 | 146篇 |
金属工艺 | 9篇 |
机械仪表 | 9篇 |
建筑科学 | 34篇 |
矿业工程 | 2篇 |
能源动力 | 34篇 |
轻工业 | 114篇 |
水利工程 | 5篇 |
石油天然气 | 3篇 |
无线电 | 63篇 |
一般工业技术 | 109篇 |
冶金工业 | 392篇 |
原子能技术 | 7篇 |
自动化技术 | 92篇 |
出版年
2022年 | 14篇 |
2021年 | 21篇 |
2020年 | 12篇 |
2019年 | 14篇 |
2018年 | 27篇 |
2017年 | 20篇 |
2016年 | 12篇 |
2015年 | 7篇 |
2014年 | 18篇 |
2013年 | 44篇 |
2012年 | 37篇 |
2011年 | 20篇 |
2010年 | 21篇 |
2009年 | 15篇 |
2008年 | 23篇 |
2007年 | 25篇 |
2006年 | 32篇 |
2005年 | 27篇 |
2004年 | 21篇 |
2003年 | 21篇 |
2002年 | 25篇 |
2001年 | 16篇 |
2000年 | 20篇 |
1999年 | 23篇 |
1998年 | 85篇 |
1997年 | 51篇 |
1996年 | 35篇 |
1995年 | 20篇 |
1994年 | 20篇 |
1993年 | 23篇 |
1992年 | 12篇 |
1991年 | 7篇 |
1990年 | 12篇 |
1988年 | 17篇 |
1987年 | 11篇 |
1986年 | 9篇 |
1985年 | 17篇 |
1984年 | 13篇 |
1983年 | 7篇 |
1982年 | 15篇 |
1981年 | 11篇 |
1980年 | 14篇 |
1979年 | 17篇 |
1978年 | 9篇 |
1977年 | 18篇 |
1976年 | 26篇 |
1975年 | 10篇 |
1969年 | 5篇 |
1968年 | 5篇 |
1960年 | 5篇 |
排序方式: 共有1031条查询结果,搜索用时 0 毫秒
91.
Harmon-Jones Eddie; Simon Linda; Greenberg Jeff; Pyszczynski Tom; Solomon Sheldon; McGregor Holly 《Canadian Metallurgical Quarterly》1997,72(1):24
On the basis of the terror management theory proposition that self-esteem provides protection against concerns about mortality, it was hypothesized that self-esteem would reduce the worldview defense produced by mortality salience (MS). The results of Exps 1 (49 undergraduates) and 2 (50 undergraduates) confirmed this hypothesis by showing that individuals with high self-esteem (manipulated in Exp 1; dispositional in Exp 2) did not respond to MS with increased worldview defense, whereas individuals with moderate self-esteem did. The results of Exp 3 (48 undergraduates) suggested that the effects of the 1st 2 experiments may have occurred because high self-esteem facilitates the suppression of death constructs following MS. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
L Hacein-Bey ES Connolly SA Mayer WL Young J Pile-Spellman RA Solomon 《Canadian Metallurgical Quarterly》1998,43(6):1304-12; discussion 1312-3
OBJECTIVE: Endovascular management of complex intracranial aneurysms is increasingly being considered as an alternative to standard surgical clipping. However, little attention has been paid to the complementary nature of surgery and endovascular therapy. METHODS: Between September 1992 and May 1997, 12 patients with complex intracranial aneurysms were treated with combined operative and endovascular methods. Seven patients demonstrated subarachnoid hemorrhage (two of Grade II, two of Grade III, and three of Grade IV). Five patients demonstrated unruptured aneurysms, i.e., three giant aneurysms (one vertebrobasilar junction aneurysm, one middle cerebral artery bifurcation aneurysm, and one internal carotid artery-ophthalmic artery aneurysm), one large internal carotid artery-ophthalmic artery aneurysm, and one middle cerebral artery serpentine aneurysm. Management strategies involved either surgery followed by endovascular therapy (S-E; n = 5) or endovascular therapy followed by surgery (E-S; n = 7). S-E paradigms included aneurysm exploration followed by endovascular treatment (S-E1; n = 3), partial aneurysm clipping followed by endovascular aneurysm packing (S-E2; n = 1), and extracranial-to-intracranial bypass followed by endovascular parent vessel occlusion (S-E3; n = 1). E-S paradigms included superselective angiography followed by surgical clipping (E-S1; n = 2), Guglielmi detachable coil partial dome packing followed by delayed surgical clipping (E-S2; n = 2), proximal temporary vessel balloon occlusion followed by aneurysm clipping (E-S3; n = 2), and proximal permanent vessel occlusion followed by surgical aneurysm decompression for mass effect treatment (E-S4; n = 1). RESULTS: Eleven aneurysms (92%) were completely eliminated. The remaining aneurysm was 90% obliterated and remained quiescent at the 34-month follow-up examination, despite presenting with subarachnoid hemorrhage. No patient experienced repeat bleeding (follow-up period, 23+/-28 mo). There were no deaths. One patient achieved a fair outcome (Glasgow Outcome Scale score of III); all other patients experienced excellent outcomes (Glasgow Outcome Scale score of I). In all cases, the aneurysm management paradigm chosen had a positive effect on definitive therapy. CONCLUSION: Several factors can contribute to the complexity of intracranial aneurysms. Management strategies that combine operative and endovascular techniques in a complementary way, for the best possible outcomes for these patients, can be designed accordingly. 相似文献
93.
GL Solomon 《Canadian Metallurgical Quarterly》1994,102(8):632-635
94.
Solomon Sondra E.; Rothblum Esther D.; Balsam Kimberly F. 《Canadian Metallurgical Quarterly》2004,18(2):275
This study compared 212 lesbians and 123 gay men who had civil unions in Vermont (during the first year legislation made this available) with 166 lesbians and 72 gay men in their friendship network who had not had civil unions, and also with 219 heterosexual married women and 193 heterosexual married men consisting of civil union couples' siblings and their spouses. Married heterosexual couples had been together longer and had more traditional division of labor and child care than did lesbians and gay men in both types of couples. Lesbians in civil unions were more open about their sexual orientation than those not in civil unions, and gay men in civil unions were closer to their family of origin than gay men not in civil unions. This is the first study on same-sex couples with civil unions, and the first to compare lesbians and gay men with their married siblings. At a time of legal changes for same-sex couples, these results indicate that legalized same-sex relationships are related to visibility of same-sex couples to their family and the general public. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Chen J. Solomon R. Chan T.-Y. Ko P.K. Hu C. 《Electron Devices, IEEE Transactions on》1992,39(10):2346-2353
96.
M Mann JH Shelhamer H Masur VJ Gill W Travis D Solomon J Manischewitz F Stock HC Lane FP Ognibene 《Canadian Metallurgical Quarterly》1997,155(5):1723-1728
This study assessed the presence of cytomegalovirus (CMV) in bronchoalveolar lavage (BAL) in three subpopulations of HIV-infected patients and correlated its presence with clinical status during 3 mo of follow-up. Nineteen asymptomatic volunteers, six patients with CMV retinitis, and 46 patients with acute pulmonary symptoms underwent BAL and were assessed for CMV by cytopathology, conventional shell vial cultures, and antigen detection. Transbronchial biopsies were also obtained when possible and evaluated for histopathologic changes of CMV. All patients were followed for approximately 3 mo. Cytomegalovirus was detected in BAL in nine of 19 (47%) asymptomatic volunteers, in all six patients with CMV retinitis, and in 33 of 46 (72%) patients with pulmonary symptoms. Only one symptomatic patient with a positive CMV BAL culture developed clinically significant CMV pulmonary disease; this patient developed disseminated CMV and died. The only other death occurred in a patient with CMV retinitis who developed staphylococcal bacteremia. None of the asymptomatic volunteers or patients with CMV retinitis developed evidence of CMV pneumonia or any other organ disease with CMV. Cytomegalovirus is frequently detected in BAL from HIV-infected patients regardless of their pulmonary symptoms and its presence does not clinically predict significant pulmonary morbidity or mortality in 3 mo of follow-up. 相似文献
97.
98.
Abstract: Establishing standards for meat tenderness based on Warner–Bratzler shear force (WBSF) is complicated by the lack of methods for certifying WBSF testing among texture systems or laboratories. The objective of this study was to determine the suitability of using gelatin gels as reference materials for performance testing of texture measurement systems. Three replications of 5 gels (15%, 20%, 25%, 30%, and 35% gelatin) were prepared, vacuum packaged, and stored at 4 °C until use. Three randomly selected strips from each gel were subjected to WBSF testing on 4 instruments (A, B, C, or D) on days 1 and 8. Additional strips from each gel were subjected to WBSF testing on instruments A and C on day 29. Regression line estimates for each set of gels were analyzed. Gel WBSF values ranged from 10 to 177 N. The WBSF by gel concentration response was highly linear (P < 0.0001) for all replications, instruments, and days of analysis. R2‐values across all sets of gels ranged from 0.9562 to 0.9998. On days 1 and 8, instruments A and D exhibited higher slope (P < 0.0001) and lower intercept (P < 0.0001) estimates than instruments B and C. Regression line parameters (slope, intercept, and R2‐values) were not influenced (P > 0.05) by length of gel storage (1, 8, and 29 d). Data from this study suggest that gelatin gels can be used for evaluating WBSF values from various instruments and for validating the performance of meat shear force testing. Practical Application: Validating the performance of meat shear force testing is vital to establishing meat tenderness standards. The gelatin gel standards developed in this study exhibited a highly linear, repeatable relationship with shear force and were found to be stable for at least a month. These gel standards would provide a tool for the meat industry to harmonize shear force measurements across laboratories and various texture measuring instruments. 相似文献
99.
Up to now, the quality of life of children and adolescents with psychiatric disorders has rarely been investigated. Not many suitable instruments are available. A new one is the "Inventory for the Assessment of the Quality of Live in Children and Adolescents" presented here. Objectives and underlying conceptual assumptions are discussed, followed by an explanation of the instrument itself (questionnaires, rating scales, etc.). Finally, experiences with the application of the instrument are reported together with initial empirical results from a clinical sample and a sample of high school students. These indicate that the instrument usefully assesses clinically relevant information about the quality of life of the patients. A broader empirical analysis of this method is being prepared. 相似文献
100.
SL Neuhausen S Mazoyer L Friedman M Stratton K Offit A Caligo G Tomlinson L Cannon-Albright T Bishop D Kelsell E Solomon B Weber F Couch J Struewing P Tonin F Durocher S Narod MH Skolnick G Lenoir O Serova B Ponder D Stoppa-Lyonnet D Easton MC King DE Goldgar 《Canadian Metallurgical Quarterly》1996,58(2):271-280
Central to the Mu transpositional recombination are the two chemical steps; donor DNA cleavage and strand transfer. These reactions occur within the Mu transpososome that contains two Mu DNA end segments bound to a tetramer of MuA, the transposase. To investigate which MuA monomer catalyzes which chemical reaction, we made transpososomes containing wild-type and active site mutant MuA. By pre-loading the MuA variants onto Mu end DNA fragments of different length prior to transpososome assembly, we could track the catalysis by MuA bound to each Mu end segment. The donor DNA end that underwent the chemical reaction was identified. Both the donor DNA cleavage and strand transfer were catalyzed in trans by the MuA monomers bound to the partner Mu end. This arrangement explains why the transpososome assembly is a prerequisite for the chemical steps. 相似文献