全文获取类型
收费全文 | 277篇 |
免费 | 29篇 |
国内免费 | 17篇 |
出版年
2023年 | 3篇 |
2022年 | 2篇 |
2021年 | 7篇 |
2020年 | 3篇 |
2016年 | 9篇 |
2015年 | 11篇 |
2014年 | 6篇 |
2013年 | 11篇 |
2012年 | 20篇 |
2011年 | 19篇 |
2010年 | 13篇 |
2009年 | 15篇 |
2008年 | 10篇 |
2007年 | 17篇 |
2006年 | 8篇 |
2005年 | 11篇 |
2004年 | 4篇 |
2003年 | 13篇 |
2002年 | 7篇 |
2001年 | 6篇 |
2000年 | 9篇 |
1999年 | 6篇 |
1998年 | 7篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 4篇 |
1991年 | 7篇 |
1989年 | 7篇 |
1988年 | 3篇 |
1987年 | 6篇 |
1986年 | 3篇 |
1985年 | 8篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1977年 | 6篇 |
1976年 | 3篇 |
1973年 | 6篇 |
1972年 | 2篇 |
1971年 | 4篇 |
1970年 | 2篇 |
1967年 | 2篇 |
1966年 | 2篇 |
1958年 | 2篇 |
1944年 | 1篇 |
1938年 | 1篇 |
排序方式: 共有323条查询结果,搜索用时 31 毫秒
1.
2.
A R Pokalsky W R Hiatt N Ridge R Rasmussen C M Houck C K Shewmaker 《Nucleic acids research》1989,17(12):4661-4673
A full-length cDNA clone, LeEF-1, has been isolated from tomato for the alpha subunit of elongation factor 1 (EF-1 alpha), a polypeptide which plays a central role in protein synthesis. The 448 amino acid protein encoded by this cDNA appears highly homologous to other EF-1 alpha s having a high degree of similarity (75-78%) to EF1 alpha previously described from both lower eukaryotes and animals. Southern analysis indicated that EF-1 alpha belongs to a small multigene family of 4-8 members in tomato. The pattern of expression of EF-1 alpha mRNA in various tomato tissues was analyzed by Northern analysis, in vitro translation and in situ hybridization. EF-1 alpha mRNA is an abundant species and higher levels of mRNA were found in developing tissues such as young leaves and green fruit compared to the mRNA levels observed in older tissues. The increased levels of EF-1 alpha mRNA therefore appear to correlate with higher levels of protein synthesis in developing tissues. 相似文献
3.
Chromosomal localization of several families of repetitive sequences by in situ hybridization. 总被引:2,自引:1,他引:1
下载免费PDF全文
![点击此处可从《American journal of human genetics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
E A Devine S L Nolin G E Houck Jr E C Jenkins W T Brown 《American journal of human genetics》1985,37(1):114-123
Four recombinant DNA clones (H1, H7, H12, and H15) carrying low-repetitive human DNA were previously isolated from a human genomic library based on their specificity for chromosome 21 and were studied for their distribution as determined by in situ hybridization. Clone H7 hybridized to the satellite regions of chromosomes 13, 14, 15, 21, and 22 as well as to the centromere region of chromosome 1. Clone H12 hybridized strongly to chromosomes 11 and 17 and the centromere of the X. Clones H1 and H15 had a very widespread distribution throughout the genome. Clone H15 hybridized significantly more to the short arm of chromosome 18 than to any other chromosomal segment. Clone H1 hybridized strongly to the centromere of chromosome 19 and also showed random distribution on all the other human chromosomes. We conclude that these probes appear to represent four repetitive families that demonstrate in situ hybridization patterns that do not correspond with those of any other repetitive family. Further, the in situ hybridization patterns do not show the strong chromosome 21 specificity originally defined by Southern blot analysis. The nature and chromosomal localization of these repetitive families should be useful in regional mapping and evolutionary studies and give additional insight into chromosomal organization. 相似文献
4.
Summary A microtechnique for the detection of DNA or RNA in small numbers of plant cells (1–50) has been developed using cauliflower mosaic virus (CaMV) infection of turnip as a model system. Both DNA and RNA extracted from 10 mesophyll protoplasts from CaMV-infected plants can be detected by hybridization using a radioactive probe made from cloned CaMV DNA (pCaMV10). No hybridization above background was detected in extracts of protoplasts from uninfected plants. At least 0.15 pg (11 000 molecules) of purified pCaMV10 DNA can be detected. This method is superior to existing macro techniques for nucleic acid detection as smaller amounts of tissue are required and the detection is approximately 100-fold more sensitive. re]19850326 rv]19850530 ac]19850611 相似文献
5.
6.
7.
Purification of Escherichia coli phosphofructokinase 总被引:3,自引:0,他引:3
C C Griffin B N Houck L Brand 《Biochemical and biophysical research communications》1967,27(3):287-293
8.
Acidic fibroblast growth factor (aFGF) stimulated DNA synthesis in primary rat hepatocyte cultures in a dose-dependent manner with maximal effect at 10-50 ng ml-1. This activity was dependent on the presence of heparin at a concentration of 10-50 micrograms.ml-1. Insulin interacted synergistically with aFGF, as it did with epidermal growth factor (EGF). The response to aFGF was only 50% that found with EGF. The disparity was not due to different kinetics of DNA synthesis, since the peak response for both growth factors occurred at 36-72 hr after plating of the hepatocytes. The potential relevance of this novel hepatocyte mitogen to normal and pathological liver growth is discussed. 相似文献
9.
10.
Anonymous nuclear DNA markers in the American oyster and their implications for the heterozygote deficiency phenomenon in marine bivalves 总被引:4,自引:0,他引:4
A puzzling population-genetic phenomenon widely reported in allozyme
surveys of marine bivalves is the occurrence of heterozygote deficits
relative to Hardy-Weinberg expectations. Possible explanations for this
pattern are categorized with respect to whether the effects should be
confined to protein-level assays or are genomically pervasive and expected
to be registered in both protein- and DNA-level assays. Anonymous nuclear
DNA markers from the American oyster were employed to reexamine the
phenomenon. In assays based on the polymerase chain reaction (PCR), two
DNA-level processes were encountered that can lead to artifactual genotypic
scorings: (a) differential amplification of alleles at a target locus and
(b) amplification from multiple paralogous loci. We describe symptoms of
these complications and prescribe methods that should generally help to
ameliorate them. When artifactual scorings at two anonymous DNA loci in the
American oyster were corrected, Hardy-Weinberg deviations registered in
preliminary population assays decreased to nonsignificant values.
Implications of these findings for the heterozygote-deficit phenomenon in
marine bivalves, and for the general development and use of PCR-based
assays, are discussed.
相似文献