全文获取类型
收费全文 | 1513篇 |
免费 | 102篇 |
国内免费 | 93篇 |
专业分类
1708篇 |
出版年
2024年 | 2篇 |
2023年 | 24篇 |
2022年 | 34篇 |
2021年 | 36篇 |
2020年 | 35篇 |
2019年 | 43篇 |
2018年 | 42篇 |
2017年 | 28篇 |
2016年 | 47篇 |
2015年 | 46篇 |
2014年 | 106篇 |
2013年 | 126篇 |
2012年 | 77篇 |
2011年 | 69篇 |
2010年 | 72篇 |
2009年 | 65篇 |
2008年 | 79篇 |
2007年 | 89篇 |
2006年 | 81篇 |
2005年 | 67篇 |
2004年 | 57篇 |
2003年 | 38篇 |
2002年 | 50篇 |
2001年 | 32篇 |
2000年 | 24篇 |
1999年 | 29篇 |
1998年 | 46篇 |
1997年 | 37篇 |
1996年 | 16篇 |
1995年 | 12篇 |
1994年 | 18篇 |
1993年 | 17篇 |
1992年 | 18篇 |
1991年 | 10篇 |
1990年 | 10篇 |
1989年 | 20篇 |
1988年 | 14篇 |
1987年 | 11篇 |
1986年 | 3篇 |
1985年 | 11篇 |
1984年 | 14篇 |
1983年 | 8篇 |
1982年 | 16篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1979年 | 8篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1974年 | 1篇 |
1973年 | 2篇 |
排序方式: 共有1708条查询结果,搜索用时 0 毫秒
1.
《Bioscience, biotechnology, and biochemistry》2013,77(3):556-560
We encountered a fourth case of honey allergy in Japan. We characterized and identified the IgE-binding proteins in honey using the serum of a honey-allergenic patient. Immunoblot analysis revealed that IgE in the patient serum specifically bound to four proteins in each honey sample. At least three of these IgE-binding proteins were N-linked glycoproteins. To identify the 60-kDa IgE-binding protein in dandelion honey, the N-terminal sequences of the fragmented protein were analyzed, revealing the protein to be major royal jelly protein 1 (MRJP 1). Three IgE-binding proteins removed of N-linked oligosaccharide showed a large reduction in IgE-binding activity as compared with the intact protein. This suggests that the carbohydrates in the IgE-binding proteins are a major epitope for patient IgE. 相似文献
2.
Nataly Mancette Rijensky Netta R. Blondheim Shraga Eilon Barnea Nir Peled Eli Rosenbaum Aron Popovtzer Solomon M. Stemmer Alejandro Livoff Mark Shlapobersky Neta Moskovits Dafna Perry Eitan Rubin Itzhak Haviv Arie Admon 《Molecular & cellular proteomics : MCP》2020,19(8):1360-1374
Highlights
- •Sufficient tumor tissues are often unavailable large HLA peptidome discovery.
- •Using patient derived xenograft (PDX) tumors can overcome this limitation.
- •The large PDX HLA peptidomes expand significantly those of the original biopsies.
- •The HLA peptidomes of the PDX tumors included many tumor antigens.
3.
Håkan Tegelström 《Biochemical genetics》1987,25(1-2):95-110
Genetic variation of mitochondrial DNA (mtDNA) in 18 great tits (Parus major) from three neighboring localities in Sweden was investigated with eight tetranucleotide restriction endonucleases. The 18 individuals could be separated into 13 different maternal lineages. The high number of female lineages present in this regional population contrasts with a low level of sequence divergence between the different mtDNA clones, with a mean of 0.19% sequence divergence between all individuals. There was no obvious spatial structuring of mtDNA clones among the three localities. The presence of a high number of different clones with a low degree of sequence divergence could be explained by the effects of a large long-term effective population size, with the mtDNA clones having diverged about 25,000–200,000 years ago.This study was supported by the Swedish Natural Science Research Council, the Erik Philip-Sörensen Foundation, and the Nilsson-Ehle Foundation. 相似文献
4.
A total of 627 cattle representing seven breeds from south central Nebraska, USA were tested for 37 BoLA antigens which behave as products of 37 distinct alleles of the class I BoLA-A locus. Four antigens were absent from all breeds tested. The other antigens showed marked and statistically significant differences in breed distribution. There was no evidence for blank (null) alleles. The number of alleles in each breed ranged from 10 to 20. The Hereford and Simmental populations tested were less polymorphic than the Angus, Brown Swiss, Charolais, Gelbvieh and Limousin populations. 相似文献
5.
6.
Summary The seasonal occurrence ofAtyaephyra desmaresti in The Netherlands has been studied by sampling the cooling-water filtering screens of power stations situated along the rivers Rhine and Meuse. The shrimps were only found in large numbers at the two power stations with vegetation in the cooling-water intake areas. Fluctuations in the seasonal occurrence showed great similarity for these two localities. Highest numbers of shrimps were impinged in November. High numbers also occurred in September, while a lower peak in numbers was found in May.Changes in the numbers of records during the last 30 years in The Netherlands were compared with climatological fluctuations (severe or mild winters), indicating that this mainly southern-European species is living here at the limits of its ecological and geographical range.The distribution in The Netherlands reveals thatAtyaephyra desmaresti mainly occurs in freshwater habitats, although it tolerates higher chlorinities. 相似文献
7.
The major developments in the field of nuclear activation analysis, from 1936 to 1989, are discussed. The developments are
grouped into five consecutive time periods. The impact of various scientists on the development of the field in the first
35 years is also discussed. 相似文献
8.
Interactive effects of ozone and soil volume on Plantago major 总被引:4,自引:2,他引:2
9.
J. W. Kadereit 《Plant biology (Stuttgart, Germany)》1994,107(6):369-373
Various explanations can be offered for the incongruence between phylogenetic hypotheses resulting from morphological and molecular data sets. Of these, the possibility that incongruence may result from the mutation of major morphogenetic genes leading to dramatic morphological divergence unaccompanied by equivalent change of the phylogenetic marker molecule(s) used is discussed in detail. As evidence for this hypothesis, several examples for such incongruence are surveyed. It seems possible that in many cases the genetic basis of the morphological characters responsible for the incongruence found may be simple, and that the genes involved may be homologous to genes known from mutant systems. It is suggested that: 1. the systematic documentation of incongruence between molecular and morphological phylogenies may help to assess the frequency of evolutionary change through the mutation of major morphogenetic genes, and that 2. the identification of major morphological characters distinguishing closely related taxa with mutant phenotypes known from mutant systems eventually may allow an experimental approach to the problem of evolutionary change resulting from major genes. Natural taxa suspected to be the result of such processes could be changed morphologically through transformation with the relevant genes. 相似文献
10.
Discrimination Amongst Leishmania by Polymerase Chain Reaction and Hybridization with Small Subunit Ribosomal DNA Derived Oligonucleotides 总被引:1,自引:0,他引:1
SILVIA R. B. ULIANA KIMBERLYN NELSON STEPHEN M. BEVERLEY ERNEY P. CAMARGO LUCILE M. FLOETER-WINTER 《The Journal of eukaryotic microbiology》1994,41(4):324-330
ABSTRACT. A method for discriminating among Leishmania is described, based upon small subunit ribosomal DNA sequence differences. The method was to amplify the entire 2.2 kb small subunit rDNA by polymerase chain reaction using conserved primers specific for the 5' and 3' termini of the small subunit ribosomal RNA, and then hybridize the product dotted onto nylon membranes with labeled oligonucleotides. The design of the hybridization probes was based upon complete small subunit rDNA sequences from L. amazonensis, L. major and L. guyanensis and partial sequences of L. mexicana, L. braziliensis, L. tropica and L. chagasi. A high degree of sequence similarity (> 99%) among species was found. However, sufficient sequence divergence occurred to permit the design of internal oligonucleotide probes specific for species complexes. This procedure successfully discriminated amongst a wide range of Leishmania isolates. The method detected as few as 10 cultured organisms and detected parasites in tissue samples from experimentally infected animals. Non-radioactive labeling showed the same specificity and sensitivity as radioactive probes. 相似文献