全文获取类型
收费全文 | 869篇 |
免费 | 0篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 3篇 |
建筑科学 | 2篇 |
轻工业 | 3篇 |
一般工业技术 | 3篇 |
冶金工业 | 857篇 |
出版年
2021年 | 1篇 |
2020年 | 1篇 |
2013年 | 1篇 |
2011年 | 1篇 |
2010年 | 2篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2004年 | 2篇 |
2003年 | 1篇 |
1999年 | 22篇 |
1998年 | 218篇 |
1997年 | 144篇 |
1996年 | 97篇 |
1995年 | 63篇 |
1994年 | 42篇 |
1993年 | 45篇 |
1992年 | 9篇 |
1991年 | 13篇 |
1990年 | 16篇 |
1989年 | 18篇 |
1988年 | 31篇 |
1987年 | 13篇 |
1986年 | 10篇 |
1985年 | 14篇 |
1982年 | 5篇 |
1981年 | 8篇 |
1980年 | 6篇 |
1977年 | 23篇 |
1976年 | 56篇 |
1975年 | 2篇 |
1955年 | 3篇 |
排序方式: 共有869条查询结果,搜索用时 15 毫秒
1.
2.
AV Stefano LF Canosa JL D'Eramo O Fridman JM Affanni GM Somoza 《Canadian Metallurgical Quarterly》1997,118(3):335-345
Gonadotropin-releasing hormone (GnRH) molecular variants in the brain and pituitary gland of pejerrey, Odontesthes bonariensis (Atheriniformes), were characterized by gradient reverse phase high performance liquid chromatography (RP-HPLC). Eluted fractions were tested in radioimmunoassays with different antisera. The results show that the brain extract contains three forms of GnRH: one is immunologically and chromatographically similar to cIIGnRH (chicken II), and another is similar to sGnRH (salmon). A third GnRH appears to be chromatographic and immunologically different from the nine other known forms of the vertebrate hormone. This is the only variant present in the pituitary gland. 相似文献
3.
4.
RC Smith JS Lyles JA Mettler AA Marshall LF Van Egeren BE Stoffelmayr GG Osborn V Shebroe 《Canadian Metallurgical Quarterly》1995,70(8):729-732
PURPOSE: To use a controlled, randomized design to assess the effect on patient satisfaction of an intensive psychosocial training program for residents. METHOD: Twenty-six first-year residents, in two internal medicine and family practice community-based programs affiliated with the Michigan State University College of Human Medicine, were randomly assigned during 1991 and 1992 to a control group or a one-month intensive training program. Experiential teaching focused on many psychosocial skills required in primary care. A 29-item questionnaire administered before and after the residents' training evaluated their patients' satisfaction regarding patient disclosure, physician empathy, confidence in physician, general satisfaction, and comparison of the physician with other physicians. Analyses of covariance with groups and gender as factors and pre-training patient satisfaction scores as the covariate evaluated the effect of the training. RESULTS: The patients of the trained residents expressed more confidence in their physicians (p = .01) and more general satisfaction (p = .02) than did the patients of controls. The effect of training on patient satisfaction with patient disclosure (p < .01) and physician empathy (p < .05) was greater for female than for male residents. CONCLUSION: The intensive psychosocial training program for residents improved their patients' satisfaction. 相似文献
5.
6.
Learning navigational maps through potentiation and modulation of hippocampal place cells 总被引:1,自引:0,他引:1
We analyze a model of navigational map formation based on correlation-based, temporally asymmetric potentiation and depression of synapses between hippocampal place cells. We show that synaptic modification during random exploration of an environment shifts the location encoded by place cell activity in such a way that it indicates the direction from any location to a fixed target avoiding walls and other obstacles. Multiple maps to different targets can be simultaneously stored if we introduce target-dependent modulation of place cell activity. Once maps to a number of target locations in a given environment have been stored, novel maps to previously unknown target locations are automatically constructed by interpolation between existing maps. 相似文献
7.
8.
LF Cooper 《Canadian Metallurgical Quarterly》1997,18(3):271-6, 278, 280-1; quiz 282
Modern restorative dentistry is confronted with many challenges related to implant use in the craniofacial region, such as attempting to place implants in esthetically critical sites or anatomically limiting regions of the jaw. To assure a successful implant placement that is satisfactory to both the patient and the dentist, four key areas need to be improved: diagnostic procedures, surgical procedures and outcomes, esthetic results, and prosthetic complications. This article discusses how an integrated approach to these areas can improve clinical practice. 相似文献
9.
10.
Pro-opiomelanocortin (POMC) is a polyhormone precursor produced predominantly in the pars distalis and pars intermedia of the pituitary gland where it undergoes tissue specific processing to produce a whole array of peptides. We have shown previously that peptides derived from the N-terminal region of POMC are involved in adrenal growth in rats. Using specific two site immunoradiometric assays we have found that the plasma of 17 week old fetal sheep contain a 50 fold excess of pro-gamma-MSH over ACTH. As term approached, the levels of pro-gamma-MSH fell and ACTH rose with evidence of fragmentation of pro-gamma-MSH, suggesting that these peptides act in concert in the development of the fetal adrenal cortex and also provide the necessary drive to bring about parturition. In an attempt to explore the pathophysiology of adrenal function we have cloned human POMC cDNA which led to the discovery of a 9bp addition/deletion mutation in the C-terminus of gamma 3-MSH between positions 67-73. Chinese hamster ovary cells (CHO) cells stably transfected with constructs containing the variant POMC cDNAs have shown a degree of partial processing. Work is currently underway to further investigate the effects of these mutations on the processing by the prohormone converting enzymes PC1 and PC2. 相似文献