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991.
There is an apparent allometric relationship between peak frequency of echolocation and body size in rhinophilids. However,
some rhinolophids deviate from this rule. To date this variation has been explained as a result of partitioning of communication
channels. An alternative hypothesis that food resource partitioning results in this divergence in expected frequencies was
tested by comparing prey selection between Rhinolophus macrotis Blyth, 1844 and Rhinolophus lepidus Blyth, 1844 in Yunnan Province, China. These two sympatric species are morphologically similar but acoustically divergent:
R. macrotis has an echolocation frequency significantly lower than that predicted by the allometric relationship, whereas that of R. lepidus agreed with expectations. Prey selection experiments, conducted in a flight tent, indicated that the dominant prey taxa of
R. macrotis were Lasiocampidae, Arctiidae and Noctuidae, whilst that of R. lepidus were Arctiidae, Noctuidae and Ichneumonidae. R. macrotis ate more earless moths and fewer eared moths than R. lepidus, and R. macrotis fed on larger prey in general and captured a wider size range than that captured by R. lepidus. These results confirmed the existence of finely tuned trophic niche differentiation and suggested that food resource partitioning
is one of the factors leading to lower peak frequency of calls in R. macrotis. 相似文献
992.
Xiaohuan Cheng Junfa Ding Fang Zheng Xin Zhou Chenling Xiong 《Molecular biology reports》2009,36(8):2053-2057
Familial hypercholesterolemia (FH) (OMIM 143890) is an autosomal dominantly inherited disease mainly caused by mutations of
the gene encoding the low density lipoprotein receptor (LDLR) and Apolipoprotein (Apo) B. First the common mutation R3500Q
in ApoB gene was determined using PCR/RFLP method. Then the LDLR gene was screened for mutations using Touch-down PCR, SSCP
and sequencing techniques. Furthermore, the secondary structure of the LDLR protein was predicted with ANTHEPROT5.0. The R3500Q
mutation was absent in these two families. A heterozygous p.W483X mutation of LDLR gene was identified in family A which caused
a premature stop codon, while a homozygous mutation p.A627T was found in family B. The predicted secondary structures of the
mutant LDLR were altered. We identified two known mutations (p.W483X, p.A627T) of the LDLR gene in two Chinese FH families
respectively. 相似文献
993.
994.
995.
Rui‐Jie Dang Yan‐Mei Yang Lei Zhang Dian‐Chao Cui Bangxing Hong Ping Li Qiuxia Lin Yan Wang Qi‐Yu Wang Fengjun Xiao Ning Mao Changyong Wang Xiao‐Xia Jiang Ning Wen 《Journal of cellular and molecular medicine》2016,20(8):1550-1560
Mesenchymal stem cells (MSCs) possess an immunoregulatory capacity and are a therapeutic target for many inflammation‐related diseases. However, the detailed mechanisms of MSC‐mediated immunosuppression remain unclear. In this study, we provide new information to partly explain the molecular mechanisms of immunoregulation by MSCs. Specifically, we found that A20 expression was induced in MSCs by inflammatory cytokines. Knockdown of A20 in MSCs resulted in increased proliferation and reduced adipogenesis, and partly reversed the suppressive effect of MSCs on T cell proliferation in vitro and inhibited tumour growth in vivo. Mechanistic studies indicated that knockdown of A20 in MSCs inhibited activation of the p38 mitogen‐activated protein kinase (MAPK) pathway, which potently promoted the production of tumour necrosis factor (TNF)‐α and inhibited the production of interleukin (IL)‐10. Collectively, these data reveal a crucial role of A20 in regulating the immunomodulatory activities of MSCs by controlling the expression of TNF‐α and IL‐10 in an inflammatory environment. These findings provide novel insights into the pathogenesis of various inflammatory‐associated diseases, and are a new reference for the future development of treatments for such afflictions. 相似文献
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997.
Qiong Wang Xianyun Ren Ping Liu Jitao Li Jianjian Lv Jiajia Wang Haien Zhang Wei Wei Yuxin Zhou Yuying He Jian Li 《Molecular ecology resources》2022,22(1):334-344
A high-quality reference genome is necessary to determine the molecular mechanisms underlying important biological phenomena; therefore, in the present study, a chromosome-level genome assembly of the Chinese shrimp Fenneropenaeus chinensis was performed. Muscle of a male shrimp was sequenced using PacBio platform, and assembled by Hi-C technology. The assembled F. chinensis genome was 1.47 Gb with contig N50 of 472.84 Kb, including 57.73% repetitive sequences, and was anchored to 43 pseudochromosomes, with scaffold N50 of 36.87 Mb. In total, 25,026 protein-coding genes were predicted. The genome size of F. chinensis showed significant contraction in comparison with that of other penaeid species, which is likely related to migration observed in this species. However, the F. chinensis genome included several expanded gene families related to cellular processes and metabolic processes, and the contracted gene families were associated with virus infection process. The findings signify the adaptation of F. chinensis to the selection pressure of migration and cold environment. Furthermore, the selection signature analysis identified genes associated with metabolism, phototransduction, and nervous system in cultured shrimps when compared with wild population, indicating targeted, artificial selection of growth, vision, and behavior during domestication. The construction of the genome of F. chinensis provided valuable information for the further genetic mechanism analysis of important biological processes, and will facilitate the research of genetic changes during evolution. 相似文献
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999.
Colorectal cancer is one of the leading causes of cancer-related deaths worldwide. Although surgical resection is still the only treatment capable of curing colon cancer, adjuvant therapy continues to play an important role in preventing recurrence and metastasis. In recent years remarkable progress has been made in the treatment of colon cancer. This review discusses recent advances in adjuvant therapy for colon cancer, including chemotherapy, immunotherapy, antiangiogenic therapy and apoptosis induction. In the meantime, molecular therapy is also elucidated in the above methods. All these new advances will provide new promises for patients of colon cancer. 相似文献
1000.
根据已知的其他物种PNAE酶cDNA序列设计引物,采用RT-PCR技术从云南萝芙木叶片中扩增获得pnae基因部分cDNA序列即PNAE酶基因中间大片段,再用RACE技术获得其两端序列。序列拼接得到完整的1 004 bp的PNAE酶基因,根据获得的序列,分析得到795 bp的开放阅读框,编码264个氨基酸。序列分析显示,云南萝芙木中PNAE酶氨基酸序列与蛇根木中的该酶氨基酸序列同源性高达90%,但和其他植物物种中的PNAE酶氨基酸序列,以及其他物种间的PNAE酶氨基酸序列同源性都不高,在40%-60%之间,表明不同物种中PNAE酶氨基酸序列不具有全序列的高度同源性。进一步序列分析发现,在各植物的PNAE酶氨基酸序列中都存在两个高度保守的氨基酸区域,表明不同物种中PNAE酶存在共同的高度保守区段。 相似文献