全文获取类型
收费全文 | 464篇 |
免费 | 0篇 |
专业分类
电工技术 | 1篇 |
化学工业 | 4篇 |
建筑科学 | 1篇 |
能源动力 | 1篇 |
轻工业 | 1篇 |
水利工程 | 1篇 |
无线电 | 1篇 |
一般工业技术 | 1篇 |
冶金工业 | 452篇 |
自动化技术 | 1篇 |
出版年
2020年 | 1篇 |
2015年 | 1篇 |
2011年 | 1篇 |
2008年 | 1篇 |
2005年 | 1篇 |
2003年 | 3篇 |
2002年 | 1篇 |
1999年 | 20篇 |
1998年 | 135篇 |
1997年 | 78篇 |
1996年 | 60篇 |
1995年 | 30篇 |
1994年 | 27篇 |
1993年 | 29篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1977年 | 23篇 |
1976年 | 22篇 |
排序方式: 共有464条查询结果,搜索用时 5 毫秒
461.
Random samples of nurses in two states which differed in abortion statues were sent questionnaires. Content areas included experience with 12 specific nursing activities associated with abortion, willingness to participate in the same activities, and extent of agreement with statements related to abortion. Attitudes toward abortion were inferred from the willingness-to-participate items and from the agreement section. These two measures correlated highly suggesting a common underlying dimension. However, the two samples differed significantly in extent of agreement but did not differ in willingness to participate. These results were interpreted as supporting the position that attitudes derived from items using situational contexts might bear a better relationship to behavior. The findings also suggest that abortion facilities can probably be staffed without violating personal preferences since so many expressed willingness to participate in at least some of the activities. Comparison across the two samples suggest that increased experience or even the potential for experience with abortion patients tended to increase the favorableness of attitudes toward this issue. 相似文献
462.
DV Pastrana N Raghavan P FitzGerald SW Eisinger C Metz R Bucala RP Schleimer C Bickel AL Scott 《Canadian Metallurgical Quarterly》1998,66(12):5955-5963
Filarial nematode parasites establish long-term chronic infections in the context of an antiparasite immunity that is strongly biased toward a Th2 response. The mechanisms that lead to this Th2 bias toward filarial antigens are not clear, but one possibility is that the parasites produce molecules that have the capacity to proactively modify their immunological environment. Here we report that filarial parasites of humans secrete a homologue of the human proinflammatory cytokine macrophage migration inhibitory factor (MIF) that has the capability of modifying the activity of human monocytes/macrophages. A cDNA clone isolated from a Brugia malayi infective-stage larva expression library encoded a 12.5-kDa protein product (Bm-MIF) with 42% identity to human and murine MIF. MIF homologues were also found to be expressed in the related filarial species Wuchereria bancrofti and Onchocerca volvulus. Bm-mif was transcribed by adult and larval parasites, and the protein product was found in somatic extracts and in the parasite's excretory-secretory products. Immunohistocytochemistry revealed that Bm-MIF was localized to cells of the hypodermis/lateral chord, the uterine wall, and larvae developing in utero. Unexpectedly, the activities of recombinant Bm-MIF and human MIF on human monocytes/macrophages were found to be similar. When placed with monocytes/macrophages in a cell migration assay, Bm-MIF inhibited random migration. When placed away from cells, Bm-MIF induced an increase in monocyte/macrophage migration that was specifically inhibited by neutralizing anti-Bm-MIF antibodies. Bm-MIF is the first demonstration that helminth parasites produce cytokine homologues that have the potential to modify host immune responses to promote parasite survival. 相似文献
463.
LM Clark WM McDonald KA Welsh-Bohmer IC Siegler DV Dawson LA Tupler KR Krishnan 《Canadian Metallurgical Quarterly》1998,44(7):592-599
Even today psychotic depression is connected to a lot of unanswered questions. A self-questionnaire (BFD) was developed in order to evaluate cognitions corresponding to mood congruent depressive delusions. They were assumed to indicate psychotic depression and to be related to severity of the depressive syndrome. 42 depressed inpatients were examined by the BFD, the Hamilton Depression Scale (HAMD) and the Beck Depression Inventory (BDI). BFD scores were found increased in psychotic depression (p = 0.009) and correlated to BDI scores (p = 0.002). 19 re-examined patients showed a significant improvement in HAMD and BDI scores but not concerning the delusion indicating cognitions (BFD), which were significantly correlated to suicidality items of BDI and HAMD (p = 0.005). The results prove the delusion indicating nature of cognitions measured by the BFD and their correlation to severe depression. Differences in treatment response are indicated and persisting or increasing BFD scores seem to be accompanied by more severe suicidal tendency. 相似文献
464.