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991.
Tatiana de Campos Paula Rodrigues Oblessuc Danilo Augusto Sfor?a Juliana Morini Kupper Cardoso Renata Moro Baroni Adna Cristina Barbosa de Sousa S��rgio Augusto Morais Carbonell Alisson Fernando Chioratto Antonio Augusto Franco Garcia Luciana Benchimol Rubiano Anete Pereira de Souza 《Molecular breeding : new strategies in plant improvement》2011,27(4):549-560
The genetic linkage map for the common bean (Phaseolus vulgaris L.) is a valuable tool for breeding programs. Breeders provide new cultivars that meet the requirements of farmers and consumers, such as seed color, seed size, maturity, and growth habit. A genetic study was conducted to examine the genetics behind certain qualitative traits. Growth habit is usually described as a recessive trait inherited by a single gene, and there is no consensus about the position of the locus. The aim of this study was to develop a new genetic linkage map using genic and genomic microsatellite markers and three morphological traits: growth habit, flower color, and pod tip shape. A mapping population consisting of 380 recombinant F10 lines was generated from IAC-UNA × CAL143. A total of 871 microsatellites were screened for polymorphisms among the parents, and a linkage map was obtained with 198 mapped microsatellites. The total map length was 1865.9 cM, and the average distance between markers was 9.4 cM. Flower color and pod tip shape were mapped and segregated at Mendelian ratios, as expected. The segregation ratio and linkage data analyses indicated that the determinacy growth habit was inherited as two independent and dominant genes, and a genetic model is proposed for this trait. 相似文献
992.
Baiotto C Sperb F Matte U da Silva CD Sano R Coelho JC Giugliani R 《Genetics and molecular biology》2011,34(1):45-48
Infantile GM1 gangliosidosis is caused by the absence or reduction of lysosomal beta-galactosidase activity. Studies conducted in Brazil have indicated that it is one of the most frequent lysosomal storage disorders in the southern part of the country. To assess the incidence of this disorder, 390 blood donors were tested for the presence of two common mutations (1622-1627insG and R59H) in the GLB1 gene. Another group, consisting of 26 GM1 patients, and the blood donors were tested for the presence of two polymorphisms (R521C and S532G), in an attempt to elucidate whether there is a founder effect. The frequencies of the R59H and 1622-1627insG mutations among the GM1 patients studied were 19.2% and 38.5%, respectively. The frequency of polymorphism S532G was 16.7%, whereas R521C was not found in the patients. The overall frequency of either R59H or 1622-1627insG was 57.7% of the disease-causing alleles. This epidemiological study suggested a carrier frequency of 1:58. Seven different haplotypes were found. The 1622-1627insG mutation was not found to be linked to any polymorphism, whereas linkage disequilibrium was found for haplotype 2 (R59H, S532G) (p < 0.001). These data confirm the high incidence of GM1 gangliosidosis and the high frequency of two common mutations in southern Brazil. 相似文献
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The work focuses on a theoretical approach to investigating the electric field (EF) dependence of bond-length alternation,
the geometric and electronic structures of molecular wires used in the design of molecular electronic devices, the EF dependence
of SCF energy, and the spatial distribution of the frontier orbitals of the molecular wires. Just as the bond length is an
important influence on the conductance of the molecular wire, the dependence of the conductance on the chain length was also
studied. We have also investigated how the current–voltage (I-V) characteristics change with bond length, as the bond length
plays an important role in determining the conductance of molecular wires. 相似文献
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998.
Banerjee S Kambhampati S Haque I Banerjee SK 《Journal of cell communication and signaling》2011,5(4):317-324
It is estimated that one in eight women will be affected with cancer during their lives, which means over 1 million women
worldwide will be diagnosed with breast cancer in the year of 2011. Roughly, 70% of breast cancer will be estrogen receptor-alpha
(ER-α) positive. The presence of ER-α is associated with better prognosis and is able to determine if tumors will respond
to the estrogen-blocking/ER-antagonist drug Tamoxifen (TAM). However, a significant fraction of ER-positive tumors respond
with minimal or no response to TAM. It is unclear why some breast cancer cells resist TAM and how to make these cells respond.
Early evidence suggests Pomegranate fruit extracts (PFEs) exhibit an anticancer effect against some cancers. The objective
of the study was to determine whether PFEs may able to enhance/sensitize the TAM’s effect in ER-positive MCF-7 breast cancer
cells. To test the hypothesis, we determined the effect of PFEs on sensitive and TAM-resistant-MCF-7 cell viability and cell
death in the presence or absence of TAM under estrogenic or non-estrogenic culture environment. The present studies demonstrated
that PFEs enhance the TAM action in both sensitive and TAM-resistant MCF-7 cells through the inhibition of cell viability
(regular or estrogen-induced) by inducing cell-death machinery. Collectively, the results showed for the first time that pomegranate
combined with TAM may represent a novel and a powerful approach to enhance and sensitize TAM action. 相似文献
999.
Grifantini R Pagani M Pierleoni A Grandi A Parri M Campagnoli S Pileri P Cattaneo D Canidio E Pontillo A De Camilli E Bresciani A Marinoni F Pedrazzoli E Nogarotto R Abrignani S Viale G Sarmientos P Grandi G 《Journal of Proteomics》2011,75(2):532-547
The YOMICS? antibody library (http://www.yomics.com/) presented in this article is a new collection of 1559 murine polyclonal antibodies specific for 1287 distinct human proteins. This antibody library is designed to target marginally characterized membrane-associated and secreted proteins. It was generated against human proteins annotated as transmembrane or secreted in GenBank, EnsEMBL, Vega and Uniprot databases, described in no or very few dedicated PubMed-linked publications. The selected proteins/protein regions were expressed in E. coli, purified and used to raise antibodies in the mouse. The capability of YOMICS? antibodies to specifically recognize their target proteins either as recombinant form or as expressed in cells and tissues was confirmed through several experimental approaches, including Western blot, confocal microscopy and immunohistochemistry (IHC). Moreover, to show the applicability of the library for biomarker investigation by IHC, five antibodies against proteins either known to be expressed in some cancers or homologous to tumor-associated proteins were tested on tissue microarrays carrying tumor and normal tissues from breast, colon, lung, ovary and prostate. A consistent differential expression in cancer was observed. Our results indicate that the YOMICS? antibody library is a tool for systematic protein expression profile analysis that nicely complements the already available commercial antibody collections. 相似文献
1000.
Facey PD Sevcikova B Novakova R Hitchings MD Crack JC Kormanec J Dyson PJ Del Sol R 《PloS one》2011,6(9):e25593
The DpsA protein plays a dual role in Streptomyces coelicolor, both as part of the stress response and contributing to nucleoid condensation during sporulation. Promoter mapping experiments indicated that dpsA is transcribed from a single, sigB-like dependent promoter. Expression studies implicate SigH and SigB as the sigma factors responsible for dpsA expression while the contribution of other SigB-like factors is indirect by means of controlling sigH expression. The promoter is massively induced in response to osmotic stress, in part due to its sensitivity to changes in DNA supercoiling. In addition, we determined that WhiB is required for dpsA expression, particularly during development. Gel retardation experiments revealed direct interaction between apoWhiB and the dpsA promoter region, providing the first evidence for a direct WhiB target in S. coelicolor. 相似文献