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BACKGROUND: Despite growing acceptance of relationships between academia and industry in the life sciences, systematic, up-to-date information about their extent and the consequences for the parties involved remains scarce. We attempted to collect information about the prevalence, magnitude, commercial benefits, and potential risks of such relationships by surveying a representative sample of life-science companies in the United States to determine their relationships with academic institutions. METHODS: We collected data by telephone from May through September 1994 from senior executives of 210 life-science companies (of 306 companies surveyed; response rate, 69 percent). The sample contained all Fortune 500 companies in the fields of agriculture, chemicals, and pharmaceuticals; all international pharmaceutical companies with sales volumes similar to those of the Fortune 500 companies; and a random sample of non-Fortune 500 companies in the life sciences drawn from multiple commercial and noncommercial directories. Both the survey instrument and the survey methods resembled those of our 1984 study of 106 biotechnology companies, allowing us to assess the evolution of relationships between academia and industry over the past decade. RESULTS: Ninety percent of companies conducting life-science research in the United States had relationships involving the life sciences with an academic institution in 1994. Fifty-nine percent supported research in such institutions, providing an estimated $1.5 billion, or approximately 11.7 percent of all research-and-development funding received that year. The agreements with universities tended to be short-term and to involve small amounts, implying that most such relationships supported applied research or development. Over 60 percent of companies providing support for life-science research in universities had received patents, products, and sales as a result of those relationships. At the same time, the companies reported that their relationships with universities often included agreements to keep the results of research secret beyond the time needed to file a patent. From 1984 to 1994, the involvement of industry with academic institutions has increased, but the characteristics of the relationships have remained remarkably stable. CONCLUSIONS: After more than a decade of sustained interaction, universities and industries seem to have formed durable partnerships in the life sciences, although the relationships may pose greater threats to the openness of scientific communication than universities generally acknowledge. However, industrial support for university research is much smaller in amount than federal support, and companies are unlikely to be able to compensate for sizable federal cutbacks.  相似文献   
994.
Summary In this paper, the polymerisation of a conjugated liquid crystalline diacetylene is reported. The structure of the polymer is discussed in relation to results from spectroscopic studies and molecular weight determinations. The polymer has a backbone structure analogous to that of other polydiacetylenes.  相似文献   
995.
A plasmid expression vector, pINSAT2, was constructed in order to express spermidine/spermine N1-acetyltransferase (SSAT) in Escherichia coli. Cells transfected with this vector produced large amounts of SSAT, amounting to up to 2% of the soluble protein when isopropyl beta-D-thiogalactopyranoside (IPTG) was added and 0.3% of the soluble protein in the absence of inducer. The growth rate of cells expressing SSAT was reduced, and all of the cellular spermidine was converted to N1-acetylspermidine, much of which was excreted. Putrescine and 1-methylspermidine, which is not a substrate for SSAT, could reverse the effects of SSAT expression on growth, but spermidine was only effective when the amount of SSAT expression was limited by omitting the IPTG inducer. The lack of stimulation of growth by spermidine correlated with its complete conversion to N1-acetylspermidine. These results show that N1-acetylspermine is not able to substitute for the unmodified polyamines in supporting growth and suggest that acetylation is a physiological response to convert excess polyamines to a physiologically inert form which is readily excreted. Cells expressing large amounts of SSAT were much more sensitive to the growth inhibitory action of the antitumor agent N1,N12-bis(ethyl)spermine, supporting the hypothesis that the ability of such bis(ethyl) polyamines to induce SSAT contributes to their antiproliferative actions. SSAT was readily purified to homogeneity from extracts of DH5 alpha cells containing pINSAT2. The purified enzyme had a similar specific activity and Km values for spermine and spermidine as the enzyme purified from human colon cancer cells, suggesting that posttranslational modifications specific to eukaryotes are not needed for enzymatic activity.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
Three methods of assessing subgroup bias in performance measurement commonly found in the literature are identified. After a review of these approaches, findings are reported from analyses of data collected in the US Army's Project A (J. P. Campbell, 1987). Correlations between nonrating performance measures and supervisor ratings were generally not moderated by race, but correlations between nonrating indicators of negative performance and ratings assigned by peers were. In addition, significant interactions between rater and ratee race on performance ratings were not eliminated when variance in the nonrating measures was removed from the ratings provided by Black and White raters. Conclusions about the magnitude and nature of bias in supervisor and peer ratings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
997.
BACKGROUND: Efficient transfer of DNA into human mesangial cells is an essential first step in the development of gene therapies for mesangial cell-mediated glomerulopathies. In the present studies, we assessed the ability of replication deficient recombinant adenovirus to transfer DNA (transduce) into primary cultures of human mesangial cells. METHODS: Primary cultures of human mesangial cells were transduced with an adenoviral vector (rAv beta-gal) containing a CMVllacZ promoter-reporter expression cassette coding for beta-galactosidase (beta-gal). We assessed soluble and histologic beta-gal activity, morphology, and phenotypic expression of mesangial cell transductants, durability of transduced mesangial cells by measuring transgene expression following trypsinization or after prolonged periods in culture and metabolic stability following transduction (as assessed by fibronectin biosynthesis). RESULTS: We showed that rAv beta-gal efficiently transduced mesangial cells in a dose-dependent fashion at a multiplicity of infectious units (MOI) ranging from 1 to 400 plaque forming units/cell (pfu/cell). One hundred percent of mesangial cells were transduced at an MOI of 100 pfu/cell. By electron microscopic evaluation, viral particles of approximately 85-90 nm were demonstrated in the cytoplasm of transduced cells. Following transduction, legal levels rose rapidly and were 10-fold greater than baseline levels after 2 hours. Beta-gal levels continued to rise for 7 days following transduction. Transduction with rAv beta-gal was well tolerated; mesangial cell transductants maintained normal morphology and phenotype, tolerated 3 cycles of trypsinization and maintained normal constitutive production of fibronectin. CONCLUSIONS: Gene transfer with adenovirus is an effective, well tolerated approach for introducing DNA into primary cultures of human mesangial cells.  相似文献   
998.
BACKGROUND: The Commit to Quit trial was designed to address the methodological problems of prior studies that have examined the contribution of exercise to smoking cessation. METHODS: This paper provides an overview of the study design and describes the sample of women who participated in this trial (N = 281). Interrelationships among eating, exercise, and smoking behavior are examined. RESULTS: Subjects randomized into the study compared with the sample of women who completed the initial assessment but were not randomized were more likely to be white, to have at least a high school education, and to smoke fewer cigarettes per day. Overall, the most frequent ineligibility criteria were health-related issues and scheduling conflicts. On average, participants in this study smoked more cigarettes per day than national samples of women smokers. Significant interrelationships include the positive association of motivational readiness for quitting smoking and enhanced levels of dietary restraint and the positive association of motivational readiness for exercise adoption and high levels of weight concern. CONCLUSIONS: This study represents the first adequately powered randomized controlled clinical trial comparing the relative efficacy of a cognitive-behavioral smoking cessation treatment plus vigorous exercise with the same treatment plus contact control.  相似文献   
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From 1995 to 1997 cataracts were observed in Atlantic salmon (Salmo salar) in Ireland, Norway and Scotland at around the time of smoltification (when freshwater fish become adapted to the hypertonic seawater) in both fresh- and seawater fish. Over 38,000 fish were screened for the presence of cataracts. Posterior cortical cataracts were the earliest and most consistent change, followed by perinuclear, equatorial and anterior cortical cataracts. On histological examination vacuolation of the lens fibres was consistently present in the posterior cortex. The pattern of the outbreak suggested that a nutritional factor was involved although the variable incidence and severity of the condition indicated that a number of modifying factors may have been involved in the expression of the condition.  相似文献   
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