全文获取类型
收费全文 | 203篇 |
免费 | 0篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 10篇 |
金属工艺 | 1篇 |
机械仪表 | 1篇 |
建筑科学 | 7篇 |
能源动力 | 1篇 |
轻工业 | 13篇 |
无线电 | 24篇 |
一般工业技术 | 8篇 |
冶金工业 | 129篇 |
自动化技术 | 8篇 |
出版年
2022年 | 1篇 |
2020年 | 1篇 |
2017年 | 1篇 |
2015年 | 1篇 |
2014年 | 1篇 |
2013年 | 4篇 |
2011年 | 4篇 |
2010年 | 2篇 |
2009年 | 3篇 |
2008年 | 3篇 |
2007年 | 3篇 |
2006年 | 4篇 |
2005年 | 3篇 |
2004年 | 3篇 |
2003年 | 5篇 |
2002年 | 8篇 |
2001年 | 4篇 |
2000年 | 4篇 |
1999年 | 9篇 |
1998年 | 16篇 |
1997年 | 14篇 |
1996年 | 15篇 |
1995年 | 8篇 |
1994年 | 10篇 |
1993年 | 5篇 |
1992年 | 5篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 6篇 |
1988年 | 9篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 5篇 |
1984年 | 2篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 5篇 |
1978年 | 1篇 |
1977年 | 1篇 |
1976年 | 4篇 |
1975年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有203条查询结果,搜索用时 265 毫秒
131.
Stiles AR Liu C Kayama Y Wong J Doner H Funston R Terry N 《Environmental science & technology》2011,45(20):8922-8927
Land damaged by boron (B) mining should be restored to its natural state with a zero net impact on biodiversity. In an earlier study (Environ. Sci. Technol.2010,44, 7089-7095), we characterized a Turkish ecotype of the grass, Puccinellia distans, which exhibited extreme tolerance to B. Here we evaluated the use of a US ecotype of P. distans as an initial vegetative cover for the phytorestoration of a B mine in southern California. Hydroponic studies revealed that this P. distans ecotype tolerated B concentrations >100 mg B/L and could be germinated and grown in B-contaminated soils taken from the sites to be restored. P. distans grew well in moderately B-contaminated soil (~88 mg B/L saturated extract) amended with added organic matter (peat moss); other soil treatments such as gypsum addition or pH correction were not needed. P. distans also grew in severely B-contaminated soil (~1506 mg B/L) provided that toxic levels of soil B were diluted by the addition of sand and/or organic matter. Our results provide evidence in support of the concept of using the US ecotype of P. distans as an initial vegetative cover for the phytorestoration of B-contaminated soil. 相似文献
132.
Vitamin B-6 is a cofactor in many reactions of nitrogen metabolism. Deficiency alters tissue amino acid concentrations but effects of excess vitamin B-6 have not been well described. We fed female rats (218 g, 7 per group) 1 (control), 10, 100, 175 or 250x) the National Research Council recommended level of pyridoxine HCl (7 mg/kg) for 10 wk and measured serum amino acids, amino acids and neurotransmitters in brain regions and the binding properties of serotonin receptors in the cerebral cortex using a ketanserin binding assay. Rats were decapitated, and unheparinized blood was obtained. In the caudate nucleus, concentrations of glutamate, threonine, taurine, methionine, gamma-amino-butyric acid and the sum of the essential amino acids in groups 10X and 100X were approximately 130 to 180% of control levels (P < 0.05); groups 1X, 175X and 250X were not different. A similar pattern was seen in the serum for serine, glycine, aspartate and ornithine; the latter two amino acids increased to over 200% of control in group 100X. In the ketanserin binding assay, both the antagonist binding affinity and the maximal number of binding sites were higher for group 100X than for 1X, 175X and 250X, and were higher for 10X than for 1X. Norepinephrine in the raphe nucleus followed a similar biphasic pattern. Excess dietary pyridoxine affected brain and serum concentrations of some amino acids and binding properties of cortical serotonin receptors in a biphasic pattern over the range of concentrations fed in this study. 相似文献
133.
Honos-Webb Lara; Stiles William B.; Greenberg Leslie S. 《Canadian Metallurgical Quarterly》2003,50(2):189
This article reports the development of a marker-based method for rating assimilation in psychotherapy with a case study of a woman, Sarah, who was treated for depression with process-experiential psychotherapy. To increase the rigor of the qualitative case study methodology, independent judges rated passages--taken out of context and randomly ordered--from the qualitative analysis. The authors examined levels of training required to make quantitative judgments by comparing ratings from 4 graduate students and 4 undergraduate students. Pooled reliabilities of the 2 groups of caters were high (.90 and .84), and the estimated reliability of single graduate student raters was acceptable (.70). Consistent findings across a series of related case studies are reviewed to address the generalizability of the findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
134.
G Yang W Zheng QR Sun XO Shu WD Li H Yu GF Shen YZ Shen JD Potter S Zheng 《Canadian Metallurgical Quarterly》1998,90(21):1661-1665
BACKGROUND: Colorectal cancer is the third most common cancer in the world, arising mostly from pre-existing adenomatous polyps (adenomas) of the large bowel. Patients with colorectal adenomas are at increased risk of colorectal cancer because of a high recurrence rate for adenomas. We followed a cohort of 1490 patients with rectal adenomas to determine whether recurrence might be related to pathologic characteristics of the initial adenomas. METHODS: The patients were identified in Haining County, China, from 1977 through 1978 by means of examination with a 15-cm rigid sigmoidoscope. They were followed by endoscopic examination at years 2, 4, 6, 11, and 16 after their initial polypectomy. New adenomas in the rectum were identified in 280 patients in these follow-up examinations. RESULTS: Statistically significant twofold to threefold elevated risks of metachronous (recurrent) adenomas were observed for patients who had more than two initial adenomas or whose most advanced initial adenoma was more than 1.0 cm in size, was of villous/tubulovillous type, or showed moderate to severe dysplasia. Much stronger associations were observed for advanced metachronous neoplasms, which are defined as cancers or adenomas with severe dysplasia, with multivariate adjusted relative risks (95% confidence interval) of 4.2 (1.8-9.9) for a large initial adenoma (>1.0 cm), 8.1 (4.2-15.6) for villous/tubulovillous architecture, and 14.4 (5.0-41.3) for severe dysplasia. In particular, patients who had a large (>1.0 cm) adenoma with severe dysplasia at baseline had a relative risk of 37 (7.8-174.7) of developing advanced metachronous neoplasms compared with patients who had small adenoma(s) with mild dysplasia. CONCLUSIONS: The risk of metachronous adenomas is closely related to the pathology of initial adenomas, thus allowing identification of a high-risk group of adenoma patients for close surveillance after their initial polypectomy. 相似文献
135.
Honos-Webb Lara; Surko Michael; Stiles William B.; Greenberg Leslie S. 《Canadian Metallurgical Quarterly》1999,46(4):448
The authors present a marker-based method for tracking the assimilation of a previously outcast voice into the self, conceived as a community of voices. In a qualitative assimilation analysis of the case of Jan, a woman whose depressive symptoms abated in process experiential psychotherapy, the authors tracked 2 major themes, excerpted 43 relevant passages, and rated each passage on the Assimilation of Problematic Experiences Scale (APES). Ratings by 3 independent raters who used a marker-based APES manual were highly correlated with the investigators' consensus ratings. APES ratings tended to increase across sessions, as expected in successful therapy. The authors present passages to illustrate the assimilation of a voice of neediness and weakness by Jan's dominant superwoman voice and the assimilation of a voice of rebellion and assertiveness by Jan's dominant good-girl voice, yielding a more complex and flexible community. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
136.
Lutz Wolfgang; Leon Scott C.; Martinovich Zoran; Lyons John S.; Stiles William B. 《Canadian Metallurgical Quarterly》2007,54(1):32
Evidence suggests that a moderate amount of variance in patient outcomes is attributable to therapist differences. However, explained variance estimates vary widely, perhaps because some therapists achieve greater success with certain kinds of patients. This study assessed the amount of variance in across-session change in symptom intensity scores explained by therapist differences in a large naturalistic data set (1,198 patients and 60 therapists, who each treated 10-77 of the patients). Results indicated that approximately 8% of the total variance and approximately 17% of the variance in rates of patient improvement could be attributed to the therapists. Cross-validation and extreme group analyses validated the existence of these therapist effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
137.
On Clutter Rank Observed by Arbitrary Arrays 总被引:2,自引:0,他引:2
This paper analyzes the rank and eigenspectrum of the clutter covariance matrix observed by space-time radar systems with arbitrarily configured arrays and varying look geometry. Motivated by recent applications that suggest use of nonuniform antenna arrays, a generalized theory of clutter rank is derived and demonstrated. First, a one-dimensional effective random process is defined by projecting the measurements obtained by an arbitrary space-time radar system into an equivalent one-dimensional sampling structure. Then, this projection and the Karhunen-Loeve representation of random processes are used to predict clutter rank based on effective aperture-bandwidth product. Simulated results are used to confirm the theory over a wide range of scenarios, and along the way, the well-known Brennan's rule for clutter rank is shown to be a special case of the proposed aperture-bandwidth product 相似文献
138.
Argues that psychological health does not conform to a single set of standards, so the "medical model" of specific treatment aimed at restoring homeostatic normality may be misleading when applied to psychotherapy. Current psychotherapeutic treatments are diverse, but no more diverse than successful patterns of living. It is suggested that different psychotherapies may open up different ranges of options for their clients and produce systematically different kinds of healthy personality change. Choice of therapy may be more a matter of personal values than of differential efficacy. (49 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
139.
YK Kwon A Bhattacharyya JA Alberta WV Giannobile K Cheon CD Stiles SL Pomeroy 《Canadian Metallurgical Quarterly》1997,17(21):8293-8299
We used anti-phosphopeptide-immunodetecting antibodies as immunohistochemical reagents to define the location and activity state of p185(erbB2) during Wallerian degeneration. Nerve damage induces a phosphorylation event at Y1248, a site that couples p185(erbB2) to the Ras-Raf-MAP kinase signal transduction pathway. Phosphorylation of p185(erbB2) occurs within Schwann cells and coincides in time and space with Schwann cell mitotic activity, as measured by bromodeoxyuridine uptake. These visual images of receptor autophosphorylation link activation of p185(erbB2) to the Schwann cell proliferation that accompanies nerve regeneration. 相似文献
140.