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71.
Cun Li Xiao-ping An Zhi-qiang Mi Da-bin Liu Huan-huan Jiang Bo Pan Sheng Wang Bin Chen Yi-gang Tong 《中国病毒学》2011,26(1):54-60
Although previous publications suggest the 2009 pandemic influenza A (H1N1) virus was reassorted from swine viruses of North
America and Eurasia, the immediate ancestry still remains elusive due to the big evolutionary distance between the 2009 H1N1
virus and the previously isolated strains. Since the unveiling of the 2009 H1N1 influenza, great deal of interest has been
drawn to influenza, consequently a large number of influenza virus sequences have been deposited into the public sequence
databases. Blast analysis demonstrated that the recently submitted 2007 South Dakota avian influenza virus strains and other
North American avian strains contained genetic segments very closely related to the 2009 H1N1 virus, which suggests these
avian influenza viruses are very close relatives of the 2009 H1N1 virus. Phylogenetic analyses also indicate that the 2009
H1N1 viruses are associated with both avian and swine influenza viruses circulating in North America. Since the migrating
wild birds are preferable to pigs as the carrier to spread the influenza viruses across vast distances, it is very likely
that birds played an important role in the inter-continental evolution of the 2009 H1N1 virus. It is essential to understand
the evolutionary route of the emerging influenza virus in order to find a way to prevent further emerging cases. This study
suggests the close relationship between 2009 pandemic virus and the North America avian viruses and underscores enhanced surveillance
of influenza in birds for understanding the evolution of the 2009 pandemic influenza. 相似文献
72.
Mi Seon Park Hyun Suk Shin Gyung-Suk Kil Jehee Lee Cheol Young Choi 《Ichthyological Research》2011,58(3):195-201
We examined changes in the expression of Na+/K+-ATPase mRNA in the gills of the cinnamon clownfish using quantitative real-time PCR in an osmotically changing environment
[seawater (35 psu; practical salinity unit, 1 psu ≈ 1‰) → brackish water (17.5 psu) and brackish water with prolactin]. The
expression of Na+/K+-ATPase mRNA in gills was increased after the transfer to brackish water, and the expression was repressed by prolactin treatment.
Also, activities of gill Na+/K+-ATPase and plasma cortisol levels increased after the transfer to brackish water and were repressed in brackish water with
prolactin treatment. Na+/K+-ATPase-immunoreactive cells were almost consistently observed in the gill filaments, but absent from the lamella epithelia.
The plasma osmolality level decreased in brackish water, but the level of this parameter increased in brackish water with
prolactin treatment during salinity change. These results suggest that the Na+/K+-ATPase gene plays an important role in osmoregulation in gills, and prolactin improves the hyperosmoregulatory ability of
cinnamon clownfish in a brackish water (hypoosmotic) environment. 相似文献
73.
A spectrophotometric assay to determine peptide transport has been developed. Using two chromogenic peptide mimetics, L-phenylalanyl-L-2-sulfanilylglycine (PSG) and L-phenylalanyl-L-3-thiaphenylalanine (PSP), the peptide transport patterns in individual cell species can be evaluated effectively. After the addition of PSG to a HeLa cell suspension, sulfanilic acid accumulated progressively inside, but not outside, the cells, demonstrating that PSG was transported wholly intact. The addition of PSP to the same cell suspension was followed immediately by extracellular thiophenol production. Measurement of the rate of thiophenol release thereby provided direct determination of PSP transport. The thiophenol release was consistent with Michaelis-Menten kinetics, with a K(m) of 0.016 mM and a V(max) of 5.07 nmol/min (1 x 10(6) cells/ml, pH 7.4, 37 degrees C). The resulting kinetic constants estimated were in agreement with values determined by single-substrate enzyme kinetics. Using PSP, transport kinetics of various dipeptides was examined by competitive spectrophotometry. As a result, dipeptides tested could be ranked in order of kinetic power for their transport. 相似文献
74.
Polycystic kidney disease (PKD) is a common genetic disorder in which extensive epithelial-lined cysts develop in the kidneys. In previous studies, abnormalities of polycystin protein and its interacting proteins, as well as primary cilia, have been suggested to play critical roles in the development of renal cysts. However, although several therapeutic targets for PKD have been suggested, no early diagnosis or effective treatments are currently available. Current developments are active for treatment of PKD including inhibitors or antagonists of PPAR-γ, TNF-α, CDK and VEGF. These drugs are potential therapeutic targets in PKD, and need to be determined about pathological functions in human PKD. It has recently been reported that the alteration of epigenetic regulation, as well as gene mutations, may affect the pathogenesis of PKD. In this review, we will discuss recent approaches to PKD therapy. It provides important information regarding potential targets for PKD. 相似文献
75.
Production of nattokinase by high cell density fed-batch culture of Bacillus subtilis 总被引:1,自引:0,他引:1
Bacillus subtilis was cultivated to high cell density for nattokinase production by pH-stat fed-batch culture. A concentrated mixture solution
of glucose and peptone was automatically added by acid-supplying pump when culture pH rose above high limit. Effect of the
ratio of glucose to peptone in feeding solution was investigated on cell growth and nattokinase production by changing the
ratio from 0.2 to 5 g glucose/g peptone. The highest cell concentration was 77 g/L when the ratio was 0.2 g glucose/g peptone.
Cell concentration decreased with increasing the ratio of glucose to peptone in feeding solution, while the optimum condition
existed for nattokinase production. The highest nattokinase activity was 14,500 unit/mL at a ratio of 0.33 g glucose/g peptone,
which was 4.3 times higher than that in batch culture. 相似文献
76.
Mi H Muruganujan A Demir E Matsuoka Y Funahashi A Kitano H Thomas PD 《Bioinformatics (Oxford, England)》2011,27(24):3437-3438
MOTIVATION: BioPAX is a standard language for representing and exchanging models of biological processes at the molecular and cellular levels. It is widely used by different pathway databases and genomics data analysis software. Currently, the primary source of BioPAX data is direct exports from the curated pathway databases. It is still uncommon for wet-lab biologists to share and exchange pathway knowledge using BioPAX. Instead, pathways are usually represented as informal diagrams in the literature. In order to encourage formal representation of pathways, we describe a software package that allows users to create pathway diagrams using CellDesigner, a user-friendly graphical pathway-editing tool and save the pathway data in BioPAX Level 3 format. AVAILABILITY: The plug-in is freely available and can be downloaded at ftp://ftp.pantherdb.org/CellDesigner/plugins/BioPAX/ CONTACT: huaiyumi@usc.edu SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online. 相似文献
77.
Chung HK Kim SW Byun SJ Ko EM Chung HJ Woo JS Yoo JG Lee HC Yang BC Kwon M Park SB Park JK Kim KW 《BMB reports》2011,44(10):686-691
Granulocyte colony-stimulating factor (G-CSF) is a cytokine secreted by stromal cells and plays a role in the differentiation of bone marrow stem cells and proliferation of neutrophils. Therefore, G-CSF is widely used to reduce the risk of serious infection in immunocompromised patients; however, its use in such patients is limited because of its non-persistent biological activity. We created an N-linked glycosylated form of this cytokine, hG-CSF (Phe140Asn), to assess its biological activity in the promyelocyte cell line HL60. Enhanced biological effects were identified by analyzing the JAK2/STAT3/survivin pathway in HL60 cells. In addition, mutant hG-CSF (Phe140Asn) was observed to have enhanced chemoattractant effects and improved differentiation efficiency in HL60 cells. These results suggest that the addition of N-linked glycosylation was successful in improving the biological activity of hG-CSF. Furthermore, the mutated product appears to be a feasible therapy for patients with neutropenia. 相似文献
78.
在胚胎发育的一定时期,表皮细胞呈现较强的β-内啡肽阳性免疫反应,而这时期正是表皮传导最活跃的时期。为了探索胚胎表皮传导和β-内啡肽-类阿片样多肽之间是否有关系,本实验采用纳络酮处理,发现表皮传导消失,待纳络酮作用消除后,表皮传导现象又再出现,说明纳络酮在胚胎表皮细胞传导中起了阻断的作用。 相似文献
79.
Summary Additon of pyruvate or leucine was found to be efficient for increasing the intracellular ratios of NADH/NAD and NADPH/NADP while reducing the coenzyme A concentration during the cultivation of Alcaligenes eutrophus. Poly--hydroxybutyrate (PHB) accumulation was enhanced more than 2-fold since metabolic flux of acetyl-CoA into PHB synthetic pathway could be facilitated by the changes of the cofactor concentrations. 相似文献
80.
Haiyan Wei Xuhua Mi Ling Ji Lichuan Yang Qingjie Xia Yuquan Wei Isamu Miyamori ChunYuan Fan 《Biochemistry. Biokhimii?a》2010,75(3):304-309
In this study, we focused on the relationship between aldosterone and NOX1 expression in vascular smooth muscle cells (VSMCs). For the first time, with the use of specific inhibitors of protein kinase
C (PKC), we report that PKCδ mediates upregulation of NOX1 induced by 10 nM aldosterone in cultured VSMCs. Participation of PKC in the mediation of NOX1 regulation was further confirmed by the effect of diacylglycerol, a PKC agonist, on the NOX1 RNA in A7r5 cells with Northern blot analysis. To establish cause and effect, we next silenced the PKCδ gene partly by RNA
interference and found knockdown of PKCδ gene attenuated aldosterone-induced NOX1 expression, generation of superoxide, as well as protein synthesis in VSMCs. Taken together, these data indicated PKCδ might
mediate aldosterone-dependent NOX1 upregulation in VSMCs. In addition, we showed that the cascade from aldosterone to PKCδ activation had the participation
of the mineralocorticoid receptor. 相似文献