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1.
Aminothiols, such as WR-2721 and its active free thiol, WR-1065, reduce mutations from ionizing radiation in exponentially growing cells. In this study, human noncycling G0 T lymphocytes were exposed in vitro to gamma-irradiation in the presence or absence of WR-1065. The five treatment groups were: (a) control; (b) treatment with 4 mM WR-1065; (c) treatment with 3 Gy of gamma-radiation, from a 137Cs source; and (d) and (e) treatment with WR-1065 30 min prior to or 3 h after 3 Gy of gamma-irradiaiton, respectively. A total of 224 cloned HPRT mutants representing 179 independent mutations were analyzed for genetic alterations using multiplex PCR. Ionizing radiation alone significantly increased the percentage of mutations with gross structural alterations compared to controls (P = 0.02). Although the frequency of such large structural mutations was not different from control cells treated with WR-1065 alone, this aminothiol significantly reduced their frequency among irradiated mutants (P = 0.01) when the radioprotector was present during the irradiation. Addition of WR-1065 3 h postirradiation also greatly reduced the percentage of gross structural alterations; however, due to small numbers, this was not statistically significant. This is the first demonstration that the antimutagenicity of WR-1065 in human cells specifically protects against these kinds of large-scale DNA alterations induced by ionizing radiation. WR-1065 and similar aminothiol compounds may afford protection against radiation-induced mutations through polyamine-like processes, e.g., stabilization of chromatin structure, inhibition of cell proliferation, and influences on DNA repair systems. 相似文献
2.
Rohrbaugh Michael J.; Shoham Varda; Coyne James C.; Cranford James A.; Sonnega John S.; Nicklas John M. 《Canadian Metallurgical Quarterly》2004,18(1):184
Ratings of patient efficacy to manage illness, made by 191 congestive heart failure patients and their spouses, were examined as predictors of patients' survival over the next 4 years. When considered alone, both the patient's self-efficacy and the spouse's confidence ratings predicted survival, but only spouse confidence remained significant when both partners" efficacy ratings were included in the same Cox regression model. The overlapping prognostic significance of spouse confidence and a global, multicomponent measure of marital quality positioned the former as a proxy for the latter, reflecting a fundamentally social protective factor in patient survival. Successful adaptation to heart failure appears to involve more than the patient's personal agency, and psychosocial data from spouses can improve prediction of patient outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Couples coping with congestive heart failure: Role and gender differences in psychological distress.
Rohrbaugh Michael J.; Cranford James A.; Shoham Varda; Nicklas John M.; Sonnega John S.; Coyne James C. 《Canadian Metallurgical Quarterly》2002,16(1):3
Psychological distress and marital quality were assessed with male (n=128) and female (n=49) congestive-heart-failure (CHF) patients and their spouses. Hopkins Symptom Check List-25 scores were in the distressed range for 57% of patients and 40% of spouses. This role difference was greater for men than for women, and a gender difference (more distress in women than men) was greater for spouses than for patients. The patient's distress, but not the spouse's, reflected the severity of the patient's illness, and distress for both partners correlated negatively with ratings of marital quality. Female-patient couples reported better relationship quality than male-patient couples, however, and a mediation analysis indicated that the gender difference in spouse distress could be explained by marital quality. Results highlight the contextual nature of CHF distress and suggest that role differences in distress vary by gender. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Jamison J. Nicklas R. Miller G. Thompson K. Wilder R. Cunningham L. Song C. 《Spectrum, IEEE》1998,35(7):38-46
The very-high-performance Backbone Network Service (vBNS) is an important part of ongoing efforts by government, industry, and academia to push the state of the art in Internet technologies and academic research applications. It is dedicated to serving research and education institutions whose scientific endeavors require networking performance not possible or not practical with commercial network services. Currently, the vBNS is implemented as an IP-over-ATM network-that is, its network layer (layer 3 of the open systems interconnection reference model promulgated by the International Organization for Standardization) runs the Internet Protocol on top of the asynchronous transfer mode protocol. Those protocols, in turn, run on a synchronous optical network (Sonet) OC-12-622.08-Mb/s-infrastructure. Though access was originally limited to five supercomputer centers and four network access points, the National Science Foundation's High-Performance Connections program is now expanding the vBNS to reach over 100 institutions. The vBNS also has connections to other research networks, both within the United States and abroad. Before describing the architecture of the vBNS, the services it provides, and the metrics developed to assess its performance, the article reviews the background against which it came into being. It also briefly discusses how the vBNS relates to the Next Generation Internet (NGI) and Internet2 相似文献
7.
Design methods have been studied by researchers for decades. Academia considers their impact on industry to be insufficient.
The objective of this research is to understand the use and impact of design methods in the context of a specific company,
Volvo Car Corporation (VCC), by describing the behaviour of engineers in relation to methods, to assist in the future development
of design methods and tools. We mainly concentrate on concept selection methods because of their relevance in this company.
The data presented is the result of qualitative research carried out during 4 years at VCC, where the authors were located
as researchers. The research shows that many methods are employed besides those with an academic name, that some in-company
methods used contain improvements to methods researched by academia, that some modifications to academic methods lead to unreliable
results, and that there is a lack of objectivity in method modification. For these reasons, the authors suggest further research
on understanding the principles of successful and unreliable modification of concept selection methods. 相似文献
8.
Holmberg A Fogel J Albertsson E Fick J Brown JN Paxéus N Förlin L Johnsson JI Larsson DG 《Journal of hazardous materials》2011,187(1-3):596-599
Citalopram is one of several selective serotonin reuptake inhibitors (SSRIs) commonly found in treated sewage effluents. Accordingly, there are concerns about possible adverse effects of SSRIs on aquatic organisms, particularly behavioural effects similar to those associated with SSRI use in humans. Rainbow trout fry and adult male guppies were therefore exposed to waterborne citalopram, ranging from environmentally relevant to high concentrations (1, 10, 100 μg/L) for 3-7 days. Under these experimental conditions citalopram does not appear to cause significant effects on aggression in rainbow trout fry or on sexual behaviour in male guppies. This may be explained by a relatively low uptake of citalopram from water to fish. 相似文献
9.
Breakfast consumption has been identified as an important factor in the nutritional well-being of children. Several studies have indicated that omission of breakfast or consumption of an inadequate breakfast is a factor contributing to poor school performance and to dietary inadequacies that are rarely compensated for in other meals of the day. Differences have also been observed in the nutrient density of the breakfast meal, depending on whether it was consumed at school or at home. Ready-to-eat cereals make a significant contribution to the nutritional quality of diets of children and young adults. The Bogalusa Heart Study, which began 25 y ago, is an epidemiologic investigation of cardiovascular risk factors and environmental determinants in a biracial pediatric population. The purpose of this review is to present data from the Bogalusa Heart Study and other studies supporting the statements above. 相似文献
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