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861.
Vahid Kia Maryam Sharif Beigli Vahedeh Hosseini Ameneh Koochaki Mahdi Paryan Samira Mohammadi-Yeganeh 《In vitro cellular & developmental biology. Animal》2018,54(9):621-628
Breast cancer is the first common cancer among women worldwide. One of the major signaling pathways playing a role in the onset and progression of this disease is PI3K/Akt/mTOR, which can be inhibited by PTEN. miRNAs are small non-coding molecules that regulate the expression of their targets by inhibition or suppression, and thus, their dysregulated expression results in the development of cancer. Using various software applications predicting miRNAs and evaluating GEO microarray data, miR-144 was selected as an inhibitor of PTEN. The expression of miR-144 and PTEN was evaluated in 18 triple negative breast cancer (TNBC) clinical samples and cell lines including 4T1, MDA-MB-231, MDA-MB-468, SK-BR-3, and MCF-7 in comparison with normal cells. PTEN and miR-144 expression analysis revealed their elevated expression in MCF-7 cells. MDA-MB-468, SK-BR-3, and MDA-MB-231 cells showed decreased levels of PTEN and increased levels of miR-144. In contrast, 4T1 cells had an increased expression of PTEN and decreased expression of miR-144. In clinical samples, miR-144 was up-regulated in 22% of the cases and PTEN was down-regulated in 78% of the cases. The results showed that the expression of PTEN and miR-144 was inversely correlated in metastatic breast cancer cell lines. However, in TNBC clinical samples, there was no correlation between the expression of miR-144 and PTEN. Literature shows that there are other influencing factors affecting the expression of miRNAs. Therefore, care should be taken in interpreting the results of gene expression studies and its relation with cancer diagnosis/prognosis. 相似文献
862.
Dan Li William Yang Carolyn Arthur Jun S. Liu Carolina Cruz-Niera Mary Qu Yang 《BMC systems biology》2018,12(7):117
Background
Adenocarcinoma in situ (AIS) is a pre-invasive lesion in the lung and a subtype of lung adenocarcinoma. The patients with AIS can be cured by resecting the lesion completely. In contrast, the patients with invasive lung adenocarcinoma have very poor 5-year survival rate. AIS can develop into invasive lung adenocarcinoma. The investigation and comparison of AIS and invasive lung adenocarcinoma at the genomic level can deepen our understanding of the mechanisms underlying lung cancer development.Results
In this study, we identified 61 lung adenocarcinoma (LUAD) invasive-specific differentially expressed genes, including nine long non-coding RNAs (lncRNAs) based on RNA sequencing techniques (RNA-seq) data from normal, AIS, and invasive tissue samples. These genes displayed concordant differential expression (DE) patterns in the independent stage III LUAD tissues obtained from The Cancer Genome Atlas (TCGA) RNA-seq dataset. For individual invasive-specific genes, we constructed subnetworks using the Genetic Algorithm (GA) based on protein-protein interactions, protein-DNA interactions and lncRNA regulations. A total of 19 core subnetworks that consisted of invasive-specific genes and at least one putative lung cancer driver gene were identified by our study. Functional analysis of the core subnetworks revealed their enrichment in known pathways and biological progresses responsible for tumor growth and invasion, including the VEGF signaling pathway and the negative regulation of cell growth.Conclusions
Our comparison analysis of invasive cases, normal and AIS uncovered critical genes that involved in the LUAD invasion progression. Furthermore, the GA-based network method revealed gene clusters that may function in the pathways contributing to tumor invasion. The interactions between differentially expressed genes and putative driver genes identified through the network analysis can offer new targets for preventing the cancer invasion and potentially increase the survival rate for cancer patients.863.
The peregrine falcon (Falco peregrinus) population in southern Scandinavia was almost extinct in the 1970’s. A successful reintroduction project was launched in
1974, using captive breeding birds of northern and southern Scandinavian, Finnish and Scottish origin. We examined the genetic
structure in the pre-bottleneck population using eleven microsatellite markers and compared the data with the previously genotyped
captive breeding population and contemporary wild population. Museum specimens between 53 and 130 years old were analyzed.
Despite an apparent loss of historical genetic diversity, the contemporary population shows a relatively high level of genetic
variation. Considerable gene introgression from captive breeding stock used to repopulate the former range of southern Scandinavian
peregrines may have altered the genetic composition of this population. Both the historical and contemporary northern and
southern Scandinavian populations are genetically differentiated. The reintroduction project implemented in the region and
the use of non-native genetic stock likely prevented the southern Scandinavian population from extinction and thus helped
maintain the level of genetic diversity and prevent inbreeding depression. The population is rapidly increasing in numbers
and range and shows no indication of reduced fitness or adaptive capabilities in the wake of the severe bottleneck and the
reintroduction. 相似文献
864.
Molecular phylogenetic analyses suggest an emerging phylogeny for the extant Placentalia (eutherian) that radically departs
from morphologically based constructions of the past. Placental mammals are partitioned into four supraordinal clades: Afrotheria,
Xenarthra, Laurasiatheria, and Euarchontoglires. Afrotheria form an endemic African clade that includes elephant shrews, golden
moles, tenrecs, aardvarks, hyraxes, elephants, dugongs, and manatees. Datamining databases of genome size (GS) shows that
till today just one afrotherian GS has been evaluated, that of the aardvark Orycteropus afer. We show that the GSs of six selected representatives across the Afrotheria supraordinal group are among the highest for
the extant Placentalia, providing a novel genomic signature of this enigmatic group. The mean GS value of Afrotheria, 5.3
± 0.7 pg, is the highest reported for the extant Placentalia. This should assist in planning new genome sequencing initiatives.
[Reviewing Editor: Dmitri Petrov] 相似文献
865.
Hung-Yen Hsieh Wen-Tseng Lo Don-Chung Liu Pei-Kai Hsu Wei-Cheng Su 《Environmental Biology of Fishes》2007,78(4):333-346
The aim of this study was to investigate the species composition and distribution of fish larvae in relation to hydrographic
conditions in the waters surrounding Taiwan Island (TI) in February 2003. In total, 242 kinds of fish larvae belonging to
127 genera and 75 families were recognized. Among these, 109 taxa were identified to the family or genus level, others to
the species level. The 12 predominant types, which constituted 71% of the total fish larvae, were Engraulis japonica, Scomber sp., Diaphus spp., Benthosema pterotum, Carangoides ferdau, Embolichthys mitsukurii, Maurolicus sp., unidentified Myctophidae, Gonostoma gracile, Trichiurus lepturus, unidentified Gobiidae, and Myctophum asperum. The distribution of fish larvae showed a clear association with water masses around TI, with higher abundances and lower
species richness northwest of TI where the China Coastal Current prevails, and lower abundances and higher species diversity
east of TI where the Kuroshio Current dominates. Cluster analysis distinguished three station groups and four species groups,
and the distribution patterns of fish larvae also corresponded to hydrographic conditions. The total abundances of fish larvae
and eight of the 12 predominant taxa showed significant and positive correlations with zooplankton abundance, which suggests
that food source might be a key factor determining the abundance and distribution of fish larvae during the winter. 相似文献
866.
Suk Hee Lee Suk Oh Young Il Kim Sang Cheol Jun Sang Sup So Hwan Gyu Kim 《Biotechnology and Bioprocess Engineering》2007,12(2):100-105
Phellinus linteus is a fungus which is found primarily in tropical regions of the Americas, Africa, and Asia.P. linteus has been used in traditional medical practice for the treatment of arthritis, liver damage and cancer. Angiogenesis is a
process that involves migration, proliferation and cell differentiation, as well as the formation of new capillary structures.
The anti-angiogenic activities evidenced by natural compounds may actually be a critical effect for the inhibition of angiogenesis-dependent
disease by these agents via the blockage of vascular development. This study assessed the effects of water extracts fromP. linteus (Phellinus extracts) on primary cultured porcine coronary artery endothelial cells (PCAECs).Phellinus extracts induced no changes in DNA synthesis or cell numbers, but inhibited the migration of PCAECs.Phellinus extracts also induced a reduction in the secretion of matrix metalloproteinase-2 (MMP-2) and MMP-9. Our results show that,
in endothelial cells,Phellinus extracts may inhibit angiogenesis by reducing levels of MMP-2 and MMP-9 secretion. 相似文献
867.
Recovery of transgenic plants by pollen-mediated transformation in <Emphasis Type="Italic">Brassica juncea</Emphasis> 总被引:1,自引:0,他引:1
The aroA-M1 encoding the mutant of 5-enolpyruvyl-shikimate-3-phosphate synthase (EPSPS) was introduced into the Brassica juncea genome by sonication-assisted, pollen-mediated transformation. The plasmid DNA and collected pollen grains were mixed in
0.3 mol/L sucrose solution and treated with mild ultrasonication. The treated pollen was then pollinated onto the oilseed
stigmas after the stamens were removed artificially. Putative transgenic plants were obtained by screening germinating seeds
on a medium containing glyphosate. Southern blot analysis of glyphosate-resistant plants indicated that the aroA-M1 gene had been integrated into the oilseed genome. Western blot analysis further confirmed that the EPSPS coded by aroA-M1 gene was expressed in transgenic plants. The transgenic plants exhibited increased resistance to glyphosate compared to untransformed
plants. Some of those transgenic plants had considerably high resistance to glyphosate. The genetic analysis of T1 progeny further confirmed that the inheritance of the introduced genes followed the Mendelian rules. The results indicated
that foreign genes can be transferred by pollen-mediated transformation combined with mild ultrasonication. 相似文献
868.
A thermophilic bacterial strain GXN151 which could degrade Avicel efficiently was isolated and identified as Bacillus licheniformis. A genomic library of GXN151 was constructed and two novel endoglucanase genes designated cel9A and cel12A were isolated by screening the library on carboxylmethyl cellulase indicator plates. The analysis of amino acid sequences deduced from the genes indicated that Cel9A consisted of a catalytic domain belonging to glycosyl hydrolase family 9, a linker domain, and a carbohydrate binding module family 3 from N-terminal to C-terminal; Cel12A had only one catalytic domain belonging to glycosyl hydrolase family 12. The combinations of Cel9A and Cel12A produced by the recombinant E. coli exhibited synergistic action against substrates of carboxylmethyl cellulose as well as Avicel. 相似文献
869.
Sediment quality criteria in use around the world 总被引:20,自引:0,他引:20
There have been numerous sediment quality guidelines (SQGs) developed during the past 20 years to assist regulators in dealing
with contaminated sediments. Unfortunately, most of these have been developed in North America. Traditionally, sediment contamination
was determined by assessing the bulk chemical concentrations of individual compounds and often comparing them with background
or reference values. Since the 1980s, SQGs have attempted to incorporate biological effects in their derivation approach.
These approaches can be categorized as empirical, frequency-based approaches to establish the relationship between sediment
contamination and toxic response, and theoretically based approaches that attempt to account for differences in bioavailability
through equilibrium partitioning (EqP) (i.e., using organic carbon or acid volatile sulfides). Some of these guidelines have
been adopted by various regulatory agencies in several countries and are being used as cleanup goals in remediation activities
and to identify priority polluted sites. The original SQGs, which compared bulk chemical concentrations to a reference or
to background, provided little insight into the ecosystem impact of sediment contaminants. Therefore, SQGs for individual
chemicals were developed that relied on field sediment chemistry paired with field or laboratory-based biological effects
data. Although some SQGs have been found to be relatively good predictors of significant site contamination, they also have
several limitations. False positive and false negative predictions are frequently in the 20% to 30% range for many chemicals
and higher for others. The guidelines are chemical specific and do not establish causality where chemical mixtures occur.
Equilibrium-based guidelines do not consider sediment ingestion as an exposure route. The guidelines do not consider spatial
and temporal variability, and they may not apply in dynamic or larger-grained sediments. Finally, sediment chemistry and bioavailability
are easily altered by sampling and subsequent manipulation processes, and therefore, measured SQGs may not reflect in situ
conditions. All the assessment tools provide useful information, but some (such as SQGs, laboratory toxicity and bioaccumulation,
and benthic indices) are prone to misinterpretation without the availability of specific in situ exposure and effects data.
SQGs should be used only in a “screening” manner or in a “weight-of-evidence” approach. Aquatic ecosystems (including sediments)
must be assessed in a “holistic” manner in which multiple components are assessed (e.g., habitat, hydrodynamics, resident
biota, toxicity, and physicochemistry, including SQGs) by using integrated approaches.
Received: December 26, 2000 / Accepted: December 28, 2001 相似文献
870.
Eutrophication assessment and bioremediation strategy in a marine fish cage culture area in Nansha Bay,China 总被引:3,自引:0,他引:3
On the basis of field data measured during four cruises from January to November 2007, variations in the characteristics of
dissolved inorganic nitrogen and phosphate were analyzed in Nansha marine fish cage culture area, Ningbo City, China. Dissolved
inorganic nitrogen (DIN) was selected as the parameter to balance seaweed absorption and fish DIN production. The contents
of DIN and phosphate varied with different seasons, and eutrophication index (E) value ranged from 2.41 to 15.99, indicating serious eutrophication conditions; the annual average value of N/P of 32.95
indicates a nitrogen surplus in this system. The eutrophication condition in Nansha Bay was mainly caused by the fish cage
culture activities. Based on their biological characteristics, Laminaria and Gracilaria were selected as the bioremediation species in winter and spring and summer and autumn, respectively. The optimal co-cultivation
proportion of fish cage to Laminaria and Gracilaria in this bay was 1 cage, 450 m2 and one cage, 690 m2, respectively. 相似文献