全文获取类型
收费全文 | 2453篇 |
免费 | 2篇 |
专业分类
化学工业 | 13篇 |
金属工艺 | 2篇 |
能源动力 | 3篇 |
轻工业 | 9篇 |
石油天然气 | 2篇 |
无线电 | 1篇 |
一般工业技术 | 5篇 |
冶金工业 | 2419篇 |
自动化技术 | 1篇 |
出版年
2022年 | 1篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2013年 | 3篇 |
2012年 | 3篇 |
2011年 | 2篇 |
2010年 | 2篇 |
2009年 | 1篇 |
2008年 | 3篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2003年 | 5篇 |
1999年 | 80篇 |
1998年 | 805篇 |
1997年 | 456篇 |
1996年 | 273篇 |
1995年 | 161篇 |
1994年 | 141篇 |
1993年 | 148篇 |
1992年 | 10篇 |
1991年 | 18篇 |
1990年 | 30篇 |
1989年 | 27篇 |
1988年 | 25篇 |
1987年 | 26篇 |
1986年 | 31篇 |
1985年 | 15篇 |
1983年 | 1篇 |
1982年 | 5篇 |
1981年 | 4篇 |
1980年 | 13篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 43篇 |
1976年 | 105篇 |
1975年 | 2篇 |
1955年 | 2篇 |
排序方式: 共有2455条查询结果,搜索用时 46 毫秒
91.
92.
KM McRoberts BP Meloni UM Morgan R Marano N Binz SL Eriandsen SA Halse RC Thompson 《Canadian Metallurgical Quarterly》1996,82(5):711-718
Following the first report of avian Giardia infection in Australia, isolates of the parasite recovered from naturally infected straw-necked ibis (Theskiornis spinicollis) were characterized using median body morphology, scanning electron microscopy, multilocus enzyme electrophoresis, random amplified polymorphic DNA (RAPD), and small subunit ribosomal RNA (SSU-rRNA) analyses. Results were compared with Giardia from other birds and mammals, and the extent of genetic diversity between a range of ibis isolates collected in Western Australia was determined. The ibis isolates of Giardia were genetically relatively homogeneous, which is in contrast to the extensive genetic heterogeneity often displayed by mammalian Giardia isolates. Morphologically, Giardia from ibis were similar to Giardia ardeae although they differed genetically and by the fact that the ibis isolates could not be established in in vitro culture. Sequence data of the DNA coding for the SSU-rRNA found a 96% homology between the ibis isolates from Western Australia and G. ardeae, suggesting that they represent distinct strains of the same species. In contrast, the ibis isolates were genetically and morphologically very different than Giardia duodenalis and Giardia muris from mammals. 相似文献
93.
SL McElroy CA Soutullo DA Beckman P Taylor PE Keck 《Canadian Metallurgical Quarterly》1998,59(4):203-10; quiz 211
BACKGROUND: The authors' objective was to provide data regarding the demographic, phenomenological, course of illness, associated psychiatric and medical comorbidity, family history, and psychiatric treatment response characteristics of rigorously diagnosed subjects who met DSM-IV criteria for intermittent explosive disorder. METHOD: Twenty-seven subjects meeting DSM-IV criteria for a current or past history of intermittent explosive disorder were given structured diagnostic interviews. The subjects' medical histories, family histories of psychiatric disorders, and responses to psychiatric treatments were also assessed. RESULTS: Most subjects described their intermittent explosive disorder symptoms as very distressing and/or highly problematic. All 27 subjects described aggressive impulses prior to their aggressive acts. Of 24 subjects who were systematically queried, 21 (88%) experienced tension with the impulses; 18 (75%), relief with the aggressive acts; and 11 (48%), pleasure with the acts. Most subjects stated that their aggressive impulses and acts were also associated with affective symptoms, particularly changes in mood and energy level. Twenty-five (93%) subjects had lifetime DSM-IV diagnoses of mood disorders; 13 (48%), substance use disorders; 13 (48%), anxiety disorders; 6 (22%), eating disorders; and 12 (44%), an impulse-control disorder other than intermittent explosive disorder. Subjects also displayed high rates of comorbid migraine headaches. First-degree relatives displayed high rates of mood, substance use, and impulse-control disorders. Twelve (60%) of 20 subjects receiving monotherapy with an antidepressant or a mood stabilizer reported moderate or marked reduction of their aggressive impulses and/or episodes. CONCLUSION: Intermittent explosive disorder appears to be a bona fide impulse-control disorder that may be related to mood disorder and may represent another form of affective spectrum disorder. 相似文献
94.
95.
EM Perchellet JB Ladesich Y Chen HS Sin DH Hua SL Kraft JP Perchellet 《Canadian Metallurgical Quarterly》1998,9(6):565-576
Methods of both linkage analysis and association analysis may be model-based or model-free. The former are useful for initial exploratory analysis, the latter for more detailed multivariate genometric analysis. Linkage leads to an association, but that association may be solely intrafamilial. Allelic association may be due to pleiotropy, linkage disequilibrium, meiotic drive, selection, or population stratification. Using non-transmitted parental alleles as controls for alleles transmitted to cases, in conjunction with a McNemar-type test, does not detect association in the absence of linkage. Model-based analyses should use models that approximate the complexity of the disease being studied in order to be both robust and powerful. 相似文献
96.
Sexually transmitted diseases are common complications of pregnancy and may have significant maternal/fetal effects. Knowledge of the symptoms and physical examination features, methods of diagnosis, indications for screening, and appropriate treatment options are essential for obstetric/gynecologic health care providers. 相似文献
97.
98.
Carbon solid phase for enzyme-linked immunosorbent assay was proposed. This support can be used instead of polysterene plates because the following steps (carbon support incubate with specific and detective reagents) are implemented in arbitrary minimal capacities. The method was tested for detection of the virus antigens (hepatitis B, herpes simplex) and anti-viral (anti-adenovirus, anti-influenza virus) antibodies. 相似文献
99.
100.
We report a patient with biopsy-proven progressive multifocal leukoencephalopathy (PML) who was serially imaged with MRI and magnetization transfer imaging. The magnetization transfer ratio (MTR) was profoundly and significantly diminished when compared with normal control subjects. The pattern of MTR was distinct from that of MS and periventricular ischemic white matter disease. Magnetization transfer imaging techniques may aid in the differential diagnosis of PML. 相似文献