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991.
Nie GX Ming H Wei DQ Zhou EM Tang X Cheng J Tang SK Li WJ 《Antonie van Leeuwenhoek》2012,101(4):753-760
A novel Gram-stain positive, aerobic, non-motile, spore-forming actinobacterium, designated YIM 75926T, was isolated from a soil sample collected at soil forest in Yuanmo county of Yunnan province, south-west China. Its taxonomic
position was investigated by a polyphasic approach. Phylogenetic analyses based on 16S rRNA gene sequences showed that the
novel strain YIM 75926T belongs to the genus Pseudonocardia and was closely related to Pseudonocardia
halophobica DSM 43089T (98.1% similarity). Strain YIM 75926T had MK-8 (H4) as the predominant menaquinone. The whole organism hydrolysates mainly consisted of meso-diaminopimelic acid, mannose, glucose, galactose and arabinose. The major cellular fatty acids were iso-C16:0 (37.16%) and C16:0 (12.43%). The DNA G+C content of strain YIM 75926T was 70.6 mol%. The resultant phylogenetic trees further showed that strain YIM 75926T belong to Pseudonocardia and had a distinct subclade within the evolutionary radiation of the genus Pseudonocardia. On the basis of its comparative analysis of phenotypic and genotypic characteristics, it is proposed that strain YIM 75926T represent a novel species of the genus Pseudonocardia, named Pseudonocardia
yuanmoensis sp. nov. The type strain is YIM 75926T (=CCTCC AA 2011017T = JCM 18055T). 相似文献
992.
Ming H Nie GX Jiang HC Yu TT Zhou EM Feng HG Tang SK Li WJ 《Antonie van Leeuwenhoek》2012,102(2):297-305
A novel cold-resistant bacterium, designated YIM 016T, was isolated from a peat bog sample collected from Mohe County, Heilongjiang Province, Northern China and its taxonomic position was investigated using a polyphasic approach. The strain was Gram-positive, aerobic, endospore-forming, motile and rod-shaped. Phylogenetic analyses based on the 16S rRNA gene sequence clearly revealed that strain YIM 016T is a member of the genus Paenibacillus. The strain is closely related to Paenibacillus alginolyticus DSM 5050T, Paenibacillus chondroitinus DSM 5051T and Paenibacillus pocheonensis Gsoil 1138T with similarities of 99.0 %, 97.0 % and 96.3 %, respectively. Meanwhile, the low DNA–DNA relatedness levels between strain YIM 016T and its closely related phylogenetic neighbours demonstrated that this isolate represents a new genomic species in the genus Paenibacillus. Phenotypic and chemotaxonomic tests showed that growth of strain YIM 016T occurred at 4–37 °C, pH 6.0–8.0 and with a NaCl tolerance up to 0.5 % (w/v). The peptidoglycan contained meso-diaminopimelic acid, alanine and glutamic acid. The whole-cell hydrolysates mainly contained glucose, galactose and ribose. The predominant menaquinone was MK-7 and the major fatty acids were anteiso-C15:0 and iso-C16:0. The DNA G+C content of strain YIM 016T was 51.7 mol %. On the basis of phylogenetic, phenotypic and chemotaxonomic characteristics, strain YIM 016T could be clearly distinguished from other species of the genus Paenibacillus. It is therefore concluded that strain YIM 016T represents a novel species in the genus Paenibacillus, for which the name Paenibacillus frigoriresistens sp. nov. is proposed. The type strain is YIM 016T (= CCTCC AB 2011150T = JCM 18141T). 相似文献
993.
994.
Fan L Wu P Zhang J Gao S Wang L Li M Sha M Xie W Nie M 《International journal of biological macromolecules》2012,50(1):31-37
Quaternary ammonium chitosan sulfates with diverse degrees of substitution (DS) ascribed to sulfate groups between 0.52 and 1.55 were synthesized by reacting quaternary ammonium chitosan with an uncommon sulfating agent (N(SO3Na)3) that was prepared from sodium bisulfite (NaHSO3) through reaction with sodium nitrite (NaNO2) in the aqueous system homogeneous. The structures of the derivatives were characterized by FTIR, 1H NMR and 13C NMR. The factors affecting DS of quaternary ammonium chitosan sulfates which included the molar ratio of NaNO2 to quaternary ammonium chitosan, sulfated temperature, sulfated time and pH of sulfated reaction solution were investigated in detail. Its anticoagulation activity in vitro was determined by an activated partial thromboplastin time (APTT) assay, a thrombin time (TT) assay and a prothrombin time (PT) assay. Results of anticoagulation assays showed quaternary ammonium chitosan sulfates significantly prolonged APTT and TT, but not PT, and demonstrated that the introduction of sulfate groups into the quaternary ammonium chitosan structure improved its anticoagulant activity obviously. The study showed its anticoagulant properties strongly depended on its DS, concentration and molecular weight. 相似文献
995.
The core-shell structure nanofibers of poly(lactic acid)/chitosan with different weight ratios were successfully electrospun from homogeneous solution. The preparation process was more simple and effective than double-needle electrospinning. The nanofibers were obtained with chitosan in shell while poly(lactic acid) in core attributing to phase separation, which were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and energy dispersive spectrometer (EDS). The electrospun nanofibrous membrane was evaluated in vitro by using mouse fibroblasts (L929) as reference cell lines. Cell culture results indicated that these materials were good in promoting cell growth and attachment, thus they could be used for tissue engineering and wound healing dressing. 相似文献
996.
This study was performed to identify and characterize the pig TDRP1 gene and to investigate its association with reproduction traits. The obtained pig TDRP1 cDNA (713 base pair [bp]) comprises a 561-bp open reading frame, which encodes a peptide of 187 amino acids. The identities of pig TDRP1 cDNA were 84.6%, 75.7%, and 77.4% with its counterparts in human, rat, and mice, respectively. Real-time polymerase chain reaction indicated that pig TDRP1 gene was highly expressed in pituitary of male and uterus of female animals. The pig TDRP1 gene contains three exons and two introns. A total of 13 single-nucleotide polymorphisms (SNPs) and 1 indel were identified in the screened partial genomic sequence, with most polymorphisms in introns. Allelic frequencies of five SNPs among eight pig breeds were further investigated, and it indicated that Landrace had the lowest genetic diversity. In Yorkshire, three SNPs (c.215+144T>C, c.215+249A>G, and c.215+672T>C) exhibited complete linkage disequilibrium in one haplotype block, and association analyses showed that all of them were significantly associated with number born alive of first parity (NBA1) (p<0.05). c.215+672T>C was also significantly associated with NBA6 (p<0.05). In addition, these three SNPs and two other ones (c.215+1001G>A and c.215+1026C>T) were associated with total born alive of second parity (TBA2) and TBA6 at the suggestive level (0.05
相似文献
997.
Wang J Huang W Xu R Nie Y Cao X Meng J Xu X Hu S Zheng Z 《Journal of cellular and molecular medicine》2012,16(9):2150-2160
Cardiac fibrosis after myocardial infarction (MI) has been identified as a key factor in the development of heart failure. Although dysregulation of microRNA (miRNA) is involved in various pathophysiological processes in the heart, the role of miRNA in fibrosis regulation after MI is not clear. Previously we observed the correlation between fibrosis and the miR-24 expression in hypertrophic hearts, herein we assessed how miR-24 regulates fibrosis after MI. Using qRT-PCR, we showed that miR-24 was down-regulated in the MI heart; the change in miR-24 expression was closely related to extracellular matrix (ECM) remodelling. In vivo, miR-24 could improve heart function and attenuate fibrosis in the infarct border zone of the heart two weeks after MI through intramyocardial injection of Lentiviruses. Moreover, in vitro experiments suggested that up-regulation of miR-24 by synthetic miR-24 precursors could reduce fibrosis and also decrease the differentiation and migration of cardiac fibroblasts (CFs). TGF-β (a pathological mediator of fibrotic disease) increased miR-24 expression, overexpression of miR-24 reduced TGF-β secretion and Smad2/3 phosphorylation in CFs. By performing microarray analyses and bioinformatics analyses, we found furin to be a potential target for miR-24 in fibrosis (furin is a protease which controls latent TGF-β activation processing). Finally, we demonstrated that protein and mRNA levels of furin were regulated by miR-24 in CFs. These findings suggest that miR-24 has a critical role in CF function and cardiac fibrosis after MI through a furin-TGF-β pathway. Thus, miR-24 may be used as a target for treatment of MI and other fibrotic heart diseases. 相似文献
998.
Wei Wang Zimin Nie Baowei Chen Feng Chen Qingtao Luo Xiaoliang Wei Guan‐Guang Xia Maria Skyllas‐Kazacos Liyu Li Zhenguo Yang 《Liver Transplantation》2012,2(4):487-493
A redox flow battery using Fe2+/Fe3+ and V2+/V3+ redox couples in chloric/sulfuric mixed‐acid supporting electrolyte is investigated for potential stationary energy storage applications. The Fe/V redox flow cell using mixed reactant solutions operates within a voltage window of 0.5–1.35 V with a nearly 100% utilization ratio and demonstrates stable cycling over 100 cycles with energy efficiency >80% and no capacity fading at room temperature. A 25% improvement in the discharge energy density of the Fe/V cell is achieved compared with a previously reported Fe/V cell using a pure chloride acid supporting electrolyte. Stable performance is achieved in the temperature range between 0 and 50 °C as well as when using a microporous separator as the membrane. The improved electrochemical performance makes the Fe/V redox flow battery a promising option as a stationary energy storage device to enable renewable integration and stabilization of the electric grid. 相似文献
999.
Improving arachidonic acid accumulation in <Emphasis Type="Italic">Mortierella alpina</Emphasis> through B-group vitamin addition 总被引:1,自引:0,他引:1
To improve the arachidonic acid (ARA) accumulation in Mortierella alpina, a mixed B-group vitamin addition strategy was developed. The ARA titer reached up to 10.0 g/L, 1.7-fold of the control.
At the same time, the highest specific activities of key enzymes involved in ARA biosynthesis, including malic enzyme, glucose-6-phosphate
dehydrogenase and ATP: citrate lyase, were 63.3, 38.6 and 53.7% higher than the control, respectively. The possible vitamin
triggered improved ARA accumulation mechanism was thus elucidated that B-group vitamins could function as the cofactors of
the key enzymes involved in ARA biosynthesis, or precursors for the formation of NADPH and acetyl-CoA which were crucial for
ARA synthesis, and strengthened the related metabolic flux. 相似文献
1000.
Jasmine A. McQuerry Jinfeng Chen Jeffrey T. Chang Andrea H. Bild 《Translational oncology》2021,14(10)
Effective cancer chemotherapy treatment requires both therapy delivery and retention by malignant cells. Cancer cell overexpression of the multidrug transmembrane transporter gene ABCB1 (MDR1, multi-drug resistance protein 1) thwarts therapy retention, leading to a drug-resistant phenotype. We explored the phenotypic impact of ABCB1 overexpression in normal human mammary epithelial cells (HMECs) via acute adenoviral delivery and in breast cancer cell lines with stable integration of inducible ABCB1 expression. One hundred sixty-two genes were differentially expressed between ABCB1-expressing and GFP-expressing HMECs, including the gene encoding the cyclooxygenase-2 protein, PTGS2. Several breast cancer cell lines with inducible ABCB1 expression demonstrated sensitivity to the 5-lipoxygenase, cyclooxygenase-1/2 inhibitor tepoxalin in two-dimensional drug response assays, and combination treatment of tepoxalin either with chemotherapies or with histone deacetylase (HDAC) inhibitors improved therapeutic efficacy in these lines. Moreover, selection for the ABCB1-expressing cell population was reduced in three-dimensional co-cultures of ABCB1-expressing and GFP-expressing cells when chemotherapy was given in combination with tepoxalin. Further study is warranted to ascertain the clinical potential of tepoxalin, an FDA-approved therapeutic for use in domesticated mammals, to restore chemosensitivity and improve drug response in patients with ABCB1-overexpressing drug-resistant breast cancers. 相似文献