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141.
利用微藻固定CO2实现碳减排的研究进展 总被引:2,自引:0,他引:2
CO2减排是目前社会经济发展所面临的重大环境问题之一,如何高效、绿色地进行减排已成为各国科研工作者关注与研究的热点。利用微藻技术进行减排符合碳循环规律,显示出很好的应用前景。本文结合笔者近年在利用微藻技术进行碳减排方面的研究工作,从固定CO2的微藻选育、微藻的培养、微藻减排在光生物反应器方面的开发以及CO2减排与污水深度处理及高价值生物质生产的耦合等4个方面对近些年来国内外在利用微藻技术实现CO2减排方面的研究情况进行了归纳与评述,并对前景进行了展望。 相似文献
142.
Severe Acute Respiratory Syndrome (SARS) is a deadly infectious disease caused by SARS Coronavirus (SARS-CoV). Inactivated
SARS-CoV has been explored as a vaccine against SARS-CoV. However, safe and potent adjuvants, especially with more efficient
and economical needle-free vaccination are always needed more urgently in a pandemic. The development of a safe and effective
mucosal adjuvant and vaccine for prevention of emergent infectious diseases such as SARS will be an important advancement.
PIKA, a stabilized derivative of Poly (I:C), was previously reported to be safe and potent as adjuvant in mouse models. In
the present study, we demonstrated that the intraperitoneal and intranasal co-administration of inactivated SARS-CoV vaccine
together with this improved Poly (I:C) derivative induced strong anti-SARS-CoV mucosal and systemic humoral immune responses
with neutralizing activity against pseudotyped virus. Although intraperitoneal immunization of inactivated SARS-CoV vaccine
alone could induce a certain level of neutralizing activity in serum as well as in mucosal sites, co-administration of inactivated
SARS-CoV vaccine with PIKA as adjuvant could induce a much higher neutralizing activity. When intranasal immunization was
used, PIKA was obligatorily for inducing neutralizing activity in serum as well as in mucosal sites and was correlated with
both mucosal IgA and mucosal IgG response. Overall, PIKA could be a good mucosal adjuvant candidate for inactivated SARS-CoV
vaccine for use in possible future pandemic. 相似文献
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144.
Bacillus thuringiensis is an insecticidal bacterium whose chitinolytic system may be exploited to improve the insecticidal system of Bt-crops. A
nucleotide fragment of 1368 bp from B. thuringiensis serovar konkukian S4, containing the complete coding sequence of the chitin binding protein Cbp50, was cloned and sequenced. Analyses have shown the protein to contain a modular structure consisting of an N-terminal CBM33 domain, two copies of a
fibronectin-like domain and a C-terminal chitin binding domain classified as CBM5. The Cbp50 protein was heterologously expressed
in Escherichia coli, purified and assessed for chitin binding activity. A deletion mutant (CBD-N; containing only the N-terminal CBM33 domain)
of Cbp50 was produced to determine the role of C-terminal domains in the binding activity of the protein. The full-length
Cbp50 was shown to bind β-chitin most efficiently followed by α-chitin, colloidal chitin and cellulose. The polysaccharide
binding activity of CBD-N was drastically decreased. The data demonstrate that both the N-terminal and C-terminal domains
of Cbp50 are essential for the efficient binding of chitin. The purified Cbp50 showed antifungal activity against the phytopathogenic
fungus Fusarium oxysporum and the opportunistic human pathogen Aspergillus niger. This is the first report of a modular chitin binding protein in bacteria. 相似文献
145.
Yanqing Le Yanhong Wang Lu Zhou Jing Xiong Jieyu Tian Xia Yang Xiaoyan Gai Yongchang Sun 《Journal of cellular and molecular medicine》2020,24(2):1319-1331
High‐mobility group box 1 (HMGB1) shows pro‐inflammatory activity in various inflammatory diseases and has been found up‐regulated in chronic obstructive pulmonary disease (COPD). Lung macrophages play an important role in airway inflammation and lung destruction in COPD, yet whether HMGB1 is involved in cigarette smoke (CS)‐induced lung macrophage dysfunction is unknown. We sought to evaluate the intracellular localization and release of HMGB1 in lung macrophages from COPD patients and CS‐exposed mice, and to investigate the role of HMGB1 in regulating autophagy in CS extract (CSE)‐treated lung macrophages (MH‐S cells). Our results showed that HMGB1 was highly expressed in lung tissues and sera of COPD patients and CS‐exposed mice, along with predominantly cytoplasmic exporting from nuclei in lung macrophages. In vitro experiments revealed that CSE promoted the expression, nucleocytoplasmic translocation and release of HMGB1 partly via the nicotinic acetylcholine receptor (nAChR). Blockade of HMGB1 with chicken anti‐HMGB1 polyclonal antibody (anti‐HMGB1) or glycyrrhizin (Gly) attenuated the increase of LC3B‐II and Beclin1, migration and p65 phosphorylation, suggesting the involvement of HMGB1 in autophagy, migration and NF‐κB activation of lung macrophages. Hydroxychloroquine (CQ), an autophagy inhibitor, enhanced the increase of LC3B‐II but not Beclin1 in CSE or rHMGB1‐treated MH‐S cells, and inhibition of autophagy by CQ and 3‐methyladenine (3‐MA) abrogated the migration and p65 phosphorylation of CSE‐treated cells. These results indicate that CS‐induced HMGB1 translocation and release contribute to migration and NF‐κB activation through inducing autophagy in lung macrophages, providing novel evidence for HMGB1 as a potential target of intervention in COPD. 相似文献
146.
147.
Ayalon G Hostettler JD Hoffman J Kizhatil K Davis JQ Bennett V 《The Journal of biological chemistry》2011,286(9):7370-7378
Costameres are cellular sites of mechanotransduction in heart and skeletal muscle where dystrophin and its membrane-spanning partner dystroglycan distribute intracellular contractile forces into the surrounding extracellular matrix. Resolution of a functional costamere interactome is still limited but likely to be critical for understanding forms of muscular dystrophy and cardiomyopathy. Dystrophin binds a set of membrane-associated proteins (the dystrophin-glycoprotein complex) as well as γ-actin and microtubules and also is required to align sarcolemmal microtubules with costameres. Ankyrin-B binds to dystrophin, dynactin-4, and microtubules and is required for sarcolemmal association of these proteins as well as dystroglycan. We report here that ankyrin-B interactions with β2 spectrin and dynactin-4 are required for localization of dystrophin, dystroglycan, and microtubules at costameres as well as protection of muscle from exercise-induced injury. Knockdown of dynactin-4 in adult mouse skeletal muscle phenocopied depletion of ankyrin-B and resulted in loss of sarcolemmal dystrophin, dystroglycan, and microtubules. Moreover, mutations of ankyrin-B and of dynactin-4 that selectively impaired binary interactions between these proteins resulted in loss of their costamere-localizing activity and increased muscle fiber fragility as a result of loss of costamere-associated dystrophin and dystroglycan. In addition, costamere-association of dynactin-4 did not require dystrophin but did depend on β2 spectrin and ankyrin-B, whereas costamere association of ankyrin-B required β2 spectrin. Together, these results are consistent with a functional hierarchy beginning with β2 spectrin recruitment of ankyrin-B to costameres. Ankyrin-B then interacts with dynactin-4 and dystrophin, whereas dynactin-4 collaborates with dystrophin in coordinating costamere-aligned microtubules. 相似文献
148.
Total nucleic acids from sporulated oocysts of Eimeria tenella isolated from Changchun in China were found to contain three extrachromosomal double-stranded RNA segments (dsRNAs) of 1.4, 2.4 and 3.6 kb in sizes. These RNAs were resistant to RNase A digestion under high salt concentration (0.3 M NaCl). RNA-dependent RNA polymerase (RDRP) activity was detected in crude extracts of E. tenella sporulated oocysts containing these nucleic acid species. Virus-like particles (VLPs) were shown to have a diameter of approximately 38 nm under Electron Microscopy (EM) after purification by sucrose density gradient centrifugation. In keeping with the nomenclature generally adopted for protozoan viruses, we have named this isolate as E. tenella virus (ETV) which is the first virus isolated from E. tenella. 相似文献
149.
150.
Wickham LA Kulick AA Gichuru L Donnelly MJ Gai CL Johnson CV Hickey EJ Nagabukuro H 《Journal of medical primatology》2011,40(5):342-350
Background Successful transurethral bladder catheterization in male non‐human primates can be challenging. An optimized approach for consistent and reproducible catheterization using a refined technique is described. Methods Under sedated and non‐sedated conditions, transurethral bladder catheterization was performed on 25 male rhesus macaques of varying ages and body weights over time. A refined technique ensuring optimal lubrication of the urethral canal prior to catheter insertion was utilized along with various single and multiple lumen catheters. Results All animals were successfully catheterized. Sixty‐five catheterization sessions were conducted with a high overall success rate (100%). The incidence of catheter (10%) and post‐catheterization (2%) complications was low. Conclusions The urinary bladder of male rhesus can be reliably and reproducibly catheterized with minimal complication using this approach. Successful catheterization was facilitated by thorough urethral lubrication and using suitable catheters. In addition, this approach may be performed without sedation on thoroughly conditioned animals. 相似文献