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181.
182.
Yasuhumi Mori Gjalt Huppes Helias A. Udo de Haes Suehiro Otoma 《The International Journal of Life Cycle Assessment》2000,5(6):327-334
To date, numerous simplified Life Cycle Assessment methods and techniques have been developed to reduce complexities associated
with practical application. However, these methods often identify critical elements according to subjective considerations.
In this paper, we develop and apply a new type of Life Cycle Inventory method — Component Manufacturing Analysis (CMA) — that
is easy to implement and less arbitrary. Application of CMA requires identification of all product components and their associated
weights, which are then entered into a factory-type database. Because the factory database has a rigorous yet generic structure
and because calculation is done automatically, the application of CMA tends to be less arbitrary and more complete than other
simplified methods. Results of a case study on beverage vending machines show that the manufacturing stage is a significant
phase in the whole life-cycle inventory of a product. We conclude that CMA shows promise for further development and future
application. 相似文献
183.
多年平均降水资源空间变化模拟方法的研究 总被引:29,自引:1,他引:28
区域多年平均降水量的研究是集水农业工程规划的基础,也是有限的降水资源合理利用和配置的依据。研究利用ARC/INFO地理信息系统,建立了研究区的栅格数字高程模型(DEM)及近30年的年均降水量空间数据库;采用9种算法(距离权重法、趋势面法、样条函数法、普通Kriging法、通用Kriging方法1、通用Kriging方法2、泰森多边形法、多元回归法和综合方法),计算并比较分析了研究区多年平均降水量的 相似文献
184.
A survey of recent publications shows that research on Phragmites australishas oftenapplied character because of the considerableecological and economic significance of the species.The main applications are water treatment, agriculture(food production or weed control) and natureconservation. In Europe, most research on natural reedstands has been motivated by reed die-back and effortstowards protection or restoration. Reed progressionand reed control have been the main concerns in otherparts of the world, and reed progression has alsoreceived increasing attention in Europe. While reeddie-back generally affects aquatic stands, progressioncan occur at both terrestrial and aquatic sites, andit can be desired (e.g. lake shore restoration)or unwanted (e.g. in species-rich fens ormarshes). Therefore, reed stands need to be assessedindividually to decide on management aims andappropriate methods. The varying status of Phragmites australisformed the background of the`European Reed Conference' held in Zürich/Switzerlandin October 1998. The seven contributions published inthis special issue are introduced with particularreference to differences between aquatic andterrestrial reed stands and to approaches used in theirassessment. 相似文献
185.
U7 small nuclear RNA (snRNA) sequences have been described only for a handful of animal species in the past. Here we describe a computational search for func- tional U7 snRNA genes throughout vertebrates including the upstream sequence elements characteristic for snRNAs transcribed by polymerase Ⅱ. Based on the results of this search, we discuss the high variability of U7 snRNAs in both se- quence and structure, and report on an attempt to find U7 snRNA sequences in basal deuterostomes and non-drosophilids insect genomes based on a combination of sequence, structure, and promoter features. Due to the extremely short se- quence and the high variability in both sequence and structure, no unambiguous candidates were found. These results cast doubt on putative U7 homologs in even more distant organisms that are reported in the most recent release of the Rfam database. 相似文献
186.
187.
The development of Internet-based virtual resources is a relatively new area of scientific and technical activity that is currently undergoing rapid expansion. Major factors fuelling recent growth include the emergence of multimedia capabilities through the rapid evolution of the World Wide Web, the reduction in cost of high quality personal computers and graphics workstations and the provision of mass-marketed provider services. Prior to 1995 the presence of Internet resources in the glycosciences was virtually non-existent. Existing scientific knowledge was primarily made available on the Net through the provision of databases from gopher and ftp sites. A particular example in the glycosciences is the Carbbank database of biological carbohydrate sequences. We will describe here our efforts in 1994–95 in establishing The Glycoscience Network (TGN, http://bellatrix.pcl.ox.ac.uk/TGN/). These activities included the establishment of a newsgroup, mailing lists, Web resources and the running of the First Electronic Glycoscience Conference (EGC-1, http://bellatrix.pcl.ox.ac.uk/egc/). EGC-1 included many novel initiatives in the glycosciences including electronic posters and papers, a Virtual Conference Centre, a Web-based hyperglossary, Virtual Trade and Employment Centres, refereed electronic publishing, and the creation of a Virtual Reality Gallery. We would like to look towards the near future and discuss several initiatives in virtual resource creation that we believe will have significant scientific impact on the glycosciences including the development of bioinformatics-based servers, sophisticated interactive databases, and videoconferencing. Furthermore, we cherish the belief that these resources will foster international scientific collaboration and progress of an extent never previously possible. Finally, we indulge in speculation and make some suggestions on the form and long-term impact of Glycoscience Virtual Resources. We predict that their development may completely reconstruct the scientific environment that we work in as scientists and we reflect on the probable benefits and pitfalls to be encountered.This paper was presented at the First Electronic Glycoscience Conference (EGCI) on the World Wide Web, September 1995. 相似文献
188.
This short paper summarises the information developed in the EU funded research project STAR on autecology databases, metrics,
multimetrics and community approaches. For Europe the WFD implementation gave an important stimulus for the development of
ecology based assessment techniques. Along with the development of metrics and multimetrics indices taxalists and autecological
information were strongly improved. Recommendations are given to further develop ecological assessment in European streams
and rivers. 相似文献
189.
High throughput protein characterization by automated reverse-phase chromatography/electrospray tandem mass spectrometry. 总被引:8,自引:0,他引:8 下载免费PDF全文
A. Ducret I. Van Oostveen J. K. Eng J. R. Yates rd R. Aebersold 《Protein science : a publication of the Protein Society》1998,7(3):706-719
We describe an integrated workstation for the automated, high-throughput, and conclusive identification of proteins by reverse-phase chromatography electrospray ionization tandem mass spectrometry. The instrumentation consists of a refrigerated autosampler, a submicrobore reverse-phase liquid chromatograph, and an electrospray triple quadrupole mass spectrometer. For protein identification, enzymatic digests of either homogeneous polypeptides or simple protein mixtures were generated and loaded into the autosampler. Samples were sequentially injected every 32 min. Ions of eluting peptides were automatically selected by the mass spectrometer and subjected to collision-induced dissociation. Following each run, the resulting tandem mass spectra were automatically analyzed by SEQUEST, a program that correlates uninterpreted peptide fragmentation patterns with amino acid sequences contained in databases. Protein identification was established by SEQUEST_SUMMARY a program that combines the SEQUEST scores of peptides originating from the same protein and ranks the cumulative results in a short summary. The workstation's performance was demonstrated by the unattended identification of 90 proteins from the yeast Saccharomyces cerevisiae, which were separated by high-resolution two-dimensional PAGE. The system was found to be very robust and identification was reliably and conclusively established for proteins if quantities exceeding 1-5 pmol were applied to the gel. The level of automation, the throughput, and the reliability of the results suggest that this system will be useful for the many projects that require the characterization of large numbers of proteins. 相似文献
190.
CD36 is a fatty acid translocase in striated muscle cells and cardiomyocytes. Some study suggested that alterations in CD36 gene may be associated with coronary artery disease (CAD) risk. The aim of the current study was to compare the frequency of CD36 variants in region encoding lipid-binding domain in Caucasian patients with early-onset CAD, no-CAD adult controls and neonates. The study group comprised 100 patients with early onset CAD. The genetic control groups were 306 infants and 40 no-CAD adults aged over 70 years. Exons 4, 5 and 6 including fragments of flanking introns were studied using the denaturing high-performance liquid chromatography technique and direct sequencing. Changes detected in analyzed fragment of CD36: IVS3-6 T/C (rs3173798), IVS4-10 G/A (rs3211892), C311T (Thr104Ile, not described so far) in exon 5, G550A (Asp184Asn, rs138897347), C572T (Pro191Leu, rs143150225), G573A (Pro191Pro, rs5956) and A591T (Thr197Thr, rs141680676) in exon 6. No significant differences in the CD36 genotype, allele and haplotype frequencies were found between the three groups. Only borderline differences (p = 0.066) were found between early onset CAD patients and newborns in the frequencies of 591T allele (2.00% vs 0.50%) and CGCGCGT haplotype (2.00% vs 0.50%) with both IVS3-6C and 591T variant alleles. In conclusion, CD36 variants: rs3173798, rs3211892, rs138897347, rs5956, rs143150225 rs141680676 and C311T do not seem to be involved in the risk of early-onset CAD in Caucasian population. 相似文献