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131.
Seasonal variation of the chemical constituents of the essential oil of Santolina etrusca from Italy
The seasonal variation of the essential oil, in terms of both yield and composition, of a population of Santolina etrusca (Asteraceae) is reported in detail for different aerial parts, including sterile branches, fertile branches, and capitula. The yields generally increased from November to June, and then decreased in August and September. The main constituents of the sterile branches were 1,8-cineole and viridiflorol. The oil from fertile branches was characterized by myrcene as principal compound, whereas the essential oil obtained from the capitula contained germacrene D as the main constituent. Several compounds, as identified by GC and GC/MS, were found to prevail during the cold season. 相似文献
132.
Ralf Buettner Le Xuan Truong Nguyen Bijender Kumar Corey Morales Chao Liu Lisa S. Chen Tea Pemovska Timothy W. Synold Joycelynne Palmer Ryan Thompson Ling Li Dinh Hoa Hoang Bin Zhang Lucy Ghoda Claudia Kowolik Mika Kontro Calum Leitch Krister Wennerberg Xiaochun Yu Ching-Cheng Chen David Horne Varsha Gandhi Vinod Pullarkat Guido Marcucci Steven T. Rosen 《Journal of cellular physiology》2019,234(9):16295-16303
133.
Mariana Ilha Ketlen da Silveira Moraes Francieli Rohden Leo Anderson Meira Martins Radovan Borojevic Guido Lenz Florencia Barbé-Tuana Fátima Costa Rodrigues Guma 《Journal of cellular biochemistry》2019,120(11):19031-19043
Caveolin-1 (Cav-1) expression is increased in hepatic stellate cells (HSC) upon liver cirrhosis and it functions as an integral membrane protein of lipid rafts and caveolae that regulates and integrates multiple signals as a platform. This study aimed to evaluate the role of Cav-1 in HSC. Thus, the effects of exogenous expression of Cav-1 in GRX cells, a model of activated HSC, were determined. Here, we demonstrated through evaluating well-known HSC activation markers – such as α-smooth muscle actin, collagen I, and glial fibrillary acidic protein – that up regulation of Cav-1 induced GRX to a more activated phenotype. GRXEGFP-Cav1 presented an increased migration, an altered adhesion pattern, a reorganization f-actin cytoskeleton, an arrested cell cycle, a modified cellular ultrastructure, and a raised endocytic flux. Based on this, GRX EGFP-Cav1 represents a new cellular model that can be an important tool for understanding of events related to HSC activation. Furthermore, our results reinforce the role of Cav-1 as a molecular marker of HSC activation. 相似文献
134.
Changzheng Song Jiao Zhao Marjorie Guichard Dongbo Shi Guido Grossmann Christian Schmitt Virginie Jouannet Thomas Greb 《Plant physiology》2022,188(1):97
Strigolactones (SLs) are a class of plant hormones that mediate biotic interactions and modulate developmental programs in response to endogenous and exogenous stimuli. However, a comprehensive view on the spatio-temporal pattern of SL signaling has not been established, and tools for a systematic in planta analysis do not exist. Here, we present Strigo-D2, a genetically encoded ratiometric SL signaling sensor that enables the examination of SL signaling distribution at cellular resolution and is capable of rapid response to altered SL levels in intact Arabidopsis (Arabidopsis thaliana) plants. By monitoring the abundance of a truncated and fluorescently labeled SUPPRESSOR OF MAX2 1-LIKE 6 (SMXL6) protein, a proteolytic target of the SL signaling machinery, we show that all cell types investigated have the capacity to respond to changes in SL levels but with very different dynamics. In particular, SL signaling is pronounced in vascular cells but low in guard cells and the meristematic region of the root. We also show that other hormones leave Strigo-D2 activity unchanged, indicating that initial SL signaling steps work in isolation from other hormonal signaling pathways. The specificity and spatio-temporal resolution of Strigo-D2 underline the value of the sensor for monitoring SL signaling in a broad range of biological contexts with highly instructive analytical depth.Strigo-D2 is a genetically encoded sensor visualizing spatio-temporal patterns of strigolactone signaling levels in intact plants based on the activity ratio of two fluorescent marker proteins. 相似文献
135.
Monoclonal antibodies against pertussis toxin subunits 总被引:2,自引:0,他引:2
Massimo Bigio Roberta Rossi Daniele Nucci Maria Giuseppina Borri Guido Antoni Antonella Bartoloni Rino Rappuoli 《FEMS microbiology letters》1988,51(1):7-11
Abstract Twenty monoclonal antibodies (mAbs) reacting with cholera toxin (CT) of Vibrio cholerae strain 569B were characterized in cross-section and GM1 ganglioside inhibition assays. MAbs were characterized by reaction with CT and Escherichia coli heat-labile porcine strain (LTp ) and human strain (LTh) enterotoxins, and by GM1 ganglioside inhibition of mAb binding. Eight of 10 CT-A specific and 3 of 10 CT-B-specific mAbs cross-reacted with LTh and LTp. GM1 ganglioside inhibited reactions of the CT-B cross-reacting antibodies. Results showed that these epitodes common to the B subunit of CT and LT are located in or near the GM1 ganglioside binding region, and that the GM1 ganglioside-binding region of LT differs from that of CT. 相似文献
136.
1. Heartbeat rate was measured in shore crabs Carcinus maenas (L.) feeding on mussels Mytilus edulis L. in order to estimate the energetic cost of handling prey and to assess the relative importance of energy and time as costing currencies.
2. Energetic handling costs represented approximately 2% of corresponding gains.
3. The tendency of profitability (gain per unit handling time) to increase with prey size was weakened by including energetic handling costs.
4. Time was judged to be a more appropriate currency than energy for costing prey-handling behaviour.
5. The importance of time as a costing currency, either through the principle of lost opportunity or through exposure to mortality risk, may extend to other behavioural systems, including aggression. 相似文献
2. Energetic handling costs represented approximately 2% of corresponding gains.
3. The tendency of profitability (gain per unit handling time) to increase with prey size was weakened by including energetic handling costs.
4. Time was judged to be a more appropriate currency than energy for costing prey-handling behaviour.
5. The importance of time as a costing currency, either through the principle of lost opportunity or through exposure to mortality risk, may extend to other behavioural systems, including aggression. 相似文献
137.
Rhizoremediation: a beneficial plant-microbe interaction 总被引:2,自引:0,他引:2
Kuiper I Lagendijk EL Bloemberg GV Lugtenberg BJ 《Molecular plant-microbe interactions : MPMI》2004,17(1):6-15
Worldwide, contamination of soil and ground water is a severe problem. The negative effects of pollutants on the environment and on human health are diverse and depend on the nature of the pollution. The search for alternative methods for excavation and incineration to clean polluted sites resulted in the application of bioremediation techniques. In this review, we describe some generally accepted bioremediation tools and subsequently focus on the combination of two approaches, phytoremediation and bioaugmentation, resulting in rhizoremediation. During rhizoremediation, exudates derived from the plant can help to stimulate the survival and action of bacteria, which subsequently results in a more efficient degradation of pollutants. The root system of plants can help to spread bacteria through soil and help to penetrate otherwise impermeable soil layers. The inoculation of pollutant-degrading bacteria on plant seed can be an important additive to improve the efficiency of phytoremediation or bioaugmentation. 相似文献
138.
Kuiper I Lagendijk EL Pickford R Derrick JP Lamers GE Thomas-Oates JE Lugtenberg BJ Bloemberg GV 《Molecular microbiology》2004,51(1):97-113
Pseudomonas putida strain PCL1445 was isolated from roots of plants, grown on a site polluted with polycyclic aromatic hydrocarbons. PCL1445 produces biosurfactant activity at the end of the exponential growth phase. High-performance liquid chromatography (HPLC) analysis of supernatant extracts of PCL1445 showed two peaks with surface-tension reducing activity, tentatively assigned as biosurfactants putisolvin I and putisolvin II and was followed by structural analyses. A transposon mutant of PCL1445, strain PCL1436, which lacks the two surface-active peaks appeared to be mutated in an open reading frame (ORF) with amino acid homology to various lipopeptide synthetases. Structural analyses of the two biosurfactants of PCL1445 revealed that both are novel cyclic lipodepsipeptides with a hexanoic lipid chain connected to the N-terminus of a 12-amino-acid peptide moiety, in which the C-terminal carboxylic acid group forms an ester with the hydroxyl side-chain of Ser9. The difference between the two structures is located in the second amino acid from the C-terminus, being valine for putisolvin I, and leucine/isoleucine for putisolvin II. We show that these novel compounds lower the surface tension and influence the biofilm development on polyvinyl chloride (PVC). Biofilm formation of the bio-synthetic mutant PCL1436 was strongly increased containing more cells, which formed aggregates earlier as compared with wild-type PCL1445 biofilms. Using purified putisolvin I and II it was shown that biofilm formation of different Pseudomonas strains was inhibited and most interestingly, that both putisolvins are also able to break down existing Pseudomonas biofilms. 相似文献
139.
Pal S Ghosh S Mandal C Kohla G Brossmer R Isecke R Merling A Schauer R Schwartz-Albiez R Bhattacharya DK Mandal C 《Glycobiology》2004,14(10):859-870
Sialic acids as terminal residues of oligosaccharide chains play crucial roles in several cellular recognition events. Exploiting the selective affinity of Achatinin-H toward N-acetyl-9-O-acetylneuraminic acid-alpha2-6-GalNAc, we have demonstrated the presence of 9-O-acetylated sialoglycoproteins (Neu5,9Ac(2)-GPs) on lymphoblasts of 70 children with acute lymphoblastic leukemia (ALL) and on leukemic cell lines by fluorimetric HPLC and flow cytometric analysis. This study aims to assess the structural aspect of the glycotope of Neu5,9Ac(2)-GPs(ALL) and to evaluate whether these disease-specific molecules can be used to monitor the clinical outcome of ALL. The Neu5,9Ac(2)-GPs(ALL) were affinity-purified, and three distinct leukemia-specific molecular determinants (135, 120, and 90 kDa) were demonstrated by SDS-PAGE, western blotting, and isoelectric focusing. The carbohydrate epitope of Neu5,9Ac(2)-GPs(ALL) was confirmed by using synthetic sialic acid analogs. The enhanced presence of anti-Neu5,9Ac(2)-GP(ALL) antibody in ALL patients prompted us to develop an antigen-ELISA using purified Neu5,9Ac(2)-GPs(ALL) as coating antigens. Purified antigen was able to detect leukemia-specific antibodies at presentation of disease, which gradually decreased with treatment. Longitudinal monitoring of 18 patients revealed that in the early phase of the treatment patients with lower anti-Neu5,9Ac(2)-GPs showed a better prognosis. Minimal cross-reactivity was observed in other hematological disorders (n = 50) like chronic myeloid leukemia, acute myelogenous leukemia, chronic lymphocytic leukemia, and non-Hodgkin's lymphoma as well as normal healthy individuals (n = 21). This study demonstrated the potential of purified Neu5,9Ac(2)-GPs(ALL) as an alternate tool for detection of anti-Neu5,9Ac(2)-GP antibodies to be helpful for diagnosis and monitoring of childhood ALL patients. 相似文献
140.
Rigobello MP Messori L Marcon G Agostina Cinellu M Bragadin M Folda A Scutari G Bindoli A 《Journal of inorganic biochemistry》2004,98(10):1634-1641
The effects of gold(I) complexes (auranofin, triethylphosphine gold and aurothiomalate), gold(III) complexes ([Au(2,2'-diethylendiamine)Cl]Cl(2), [(Au(2-(1,1-dimethylbenzyl)-pyridine) (CH(3)COO)(2)], [Au(6-(1,1-dimethylbenzyl)-2,2'-bipyridine)(OH)](PF(6)), [Au(bipy(dmb)-H)(2,6-xylidine)](PF(6))), metal ions (zinc and cadmium acetate) and metal complexes (cisplatin, zinc pyrithione and tributyltin) on mitochondrial thioredoxin reductase and mitochondrial functions have been examined. Both gold(I) and gold(III) complexes are extremely efficient inhibitors of thioredoxin reductase showing IC(50) ranging from 0.020 to 1.42 microM while metal ions and complexes not containing gold are less effective, exhibiting IC(50) going from 11.8 to 76.0 microM. At variance with thioredoxin reductase, auranofin is completely ineffective in inhibiting glutathione peroxidase and glutathione reductase, while gold(III) compounds show some effect on glutathione peroxidase. The mitochondrial respiratory chain is scarcely affected by gold compounds while the other metal complexes and metal ions, in particular zinc ion and zinc pyrithione, show a more marked inhibitory effect that is reflected on a rapid induction of membrane potential decrease that precedes swelling. Therefore, differently from gold compounds, the various metal ions and metal complexes exert their effect on different targets indicating a lower specificity. It is concluded that gold compounds are highly specific inhibitors of mitochondrial thioredoxin reductase and this action influences other functions such as membrane permeability properties. Metal ions and metal complexes markedly inhibit the activity of thioredoxin reductase although to an extent lower than that of gold compounds. They also inhibit mitochondrial respiration, decrease membrane potential and, finally, induce swelling. 相似文献