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171.
172.
Colares Tamiris Gago de Figueiredo Camila Saggioro de Oliveira Jesus Souza Lucienne dos Santos Aline Araujo Giestal-de-Araujo Elizabeth 《Neurochemical research》2021,46(7):1701-1716
Neurochemical Research - Interleukin-2 (IL-2) is a classical pro-inflammatory cytokine known to display neuroprotective roles in the central nervous system including the retina. In the present... 相似文献
173.
Melanie Brügger Thomas Dmoulins G. Tuba Barut Beatrice Zumkehr Blandina I. Oliveira Esteves Kemal Mehinagic Quentin Haas Aline Schgler Marie-Anne Rameix-Welti Jean-Franois Elouët Ueli Moehrlen Thomas M. Marti Ralph A. Schmid Artur Summerfield Horst Posthaus Nicolas Ruggli Sean R. R. Hall Marco P. Alves 《PLoS pathogens》2021,17(7)
174.
175.
Renal clearance of quantum dots 总被引:9,自引:0,他引:9
Choi HS Liu W Misra P Tanaka E Zimmer JP Itty Ipe B Bawendi MG Frangioni JV 《Nature biotechnology》2007,25(10):1165-1170
The field of nanotechnology holds great promise for the diagnosis and treatment of human disease. However, the size and charge of most nanoparticles preclude their efficient clearance from the body as intact nanoparticles. Without such clearance or their biodegradation into biologically benign components, toxicity is potentially amplified and radiological imaging is hindered. Using intravenously administered quantum dots in rodents as a model system, we have precisely defined the requirements for renal filtration and urinary excretion of inorganic, metal-containing nanoparticles. Zwitterionic or neutral organic coatings prevented adsorption of serum proteins, which otherwise increased hydrodynamic diameter by >15 nm and prevented renal excretion. A final hydrodynamic diameter <5.5 nm resulted in rapid and efficient urinary excretion and elimination of quantum dots from the body. This study provides a foundation for the design and development of biologically targeted nanoparticles for biomedical applications. 相似文献
176.
Giselle Pidde-Queiroz Fábio Carlos Magnoli Fernanda C. V. Portaro Solange M. T. Serrano Aline Soriano Lopes Adriana Franco Paes Leme Carmen W. van den Berg Denise V. Tambourgi 《PLoS neglected tropical diseases》2013,7(10)
Background
Snake Venom Metalloproteinases (SVMPs) are amongst the key enzymes that contribute to the high toxicity of snake venom. We have recently shown that snake venoms from the Bothrops genus activate the Complement system (C) by promoting direct cleavage of C-components and generating anaphylatoxins, thereby contributing to the pathology and spread of the venom. The aim of the present study was to isolate and characterize the C-activating protease from Bothrops pirajai venom.Results
Using two gel-filtration chromatography steps, a metalloproteinase of 23 kDa that activates Complement was isolated from Bothrops pirajai venom. The mass spectrometric identification of this protein, named here as C-SVMP, revealed peptides that matched sequences from the P-I class of SVMPs. C-SVMP activated the alternative, classical and lectin C-pathways by cleaving the α-chain of C3, C4 and C5, thereby generating anaphylatoxins C3a, C4a and C5a. In vivo, C-SVMP induced consumption of murine complement components, most likely by activation of the pathways and/or by direct cleavage of C3, leading to a reduction of serum lytic activity.Conclusion
We show here that a P-I metalloproteinase from Bothrops pirajai snake venom activated the Complement system by direct cleavage of the central C-components, i.e., C3, C4 and C5, thereby generating biologically active fragments, such as anaphylatoxins, and by cleaving the C1-Inhibitor, which may affect Complement activation control. These results suggest that direct complement activation by SVMPs may play a role in the progression of symptoms that follow envenomation. 相似文献177.
Frischknecht F Baldacci P Martin B Zimmer C Thiberge S Olivo-Marin JC Shorte SL Ménard R 《Cellular microbiology》2004,6(7):687-694
Malaria is contracted when Plasmodium sporozoites are inoculated into the vertebrate host during the blood meal of a mosquito. In infected mosquitoes, sporozoites are present in large numbers in the secretory cavities of the salivary glands at the most distal site of the salivary system. However, how sporozoites move through the salivary system of the mosquito, both in resting and feeding mosquitoes, is unknown. Here, we observed fluorescent Plasmodium berghei sporozoites within live Anopheles stephensi mosquitoes and their salivary glands and ducts. We show that sporozoites move in the mosquito by gliding, a type of motility associated with their capacity to invade host cells. Unlike in vitro, sporozoite gliding inside salivary cavities and ducts is modulated in speed and motion pattern. Imaging of sporozoite discharge through the proboscis of salivating mosquitoes indicates that sporozoites need to locomote from cavities into ducts to be ejected and that their progression inside ducts favours their early ejection. These observations suggest that sporozoite gliding allows not only for cell invasion but also for parasite locomotion in host tissues, and that it may control parasite transmission. 相似文献
178.
Inventory and monitoring of wine microbial consortia 总被引:2,自引:0,他引:2
The evolution of the wine microbial ecosystem is generally restricted to Saccharomyces cerevisiae and Oenococcus oeni, which are the two main agents in the transformation of grape must into wine by acting during alcoholic and malolactic fermentation,
respectively. But others species like the yeast Brettanomyces bruxellensis and certain ropy strains of Pediococcus parvulus can spoil the wine. The aim of this study was to address the composition of the system more precisely, identifying other
components. The advantages of the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) approach to
wine microbial ecology studies are illustrated by bacteria and yeast species identification and their monitoring at each stage
of wine production. After direct DNA extraction, PCR-DGGE was used to make the most exhaustive possible inventory of bacteria
and yeast species found in a wine environment. Phylogenetic neighbor-joining trees were built to illustrate microbial diversity.
PCR-DGGE was also combined with population enumeration in selective media to monitor microbial changes at all stages of production.
Moreover, enrichment media helped to detect the appearance of spoilage species. The genetic diversity of the wine microbial
community and its dynamics during winemaking were also described. Most importantly, our study provides a better understanding
of the complexity and diversity of the wine microbial consortium at all stages of the winemaking process: on grape berries,
in must during fermentation, and in wine during aging. On grapes, 52 different yeast species and 40 bacteria could be identified.
The diversity was dramatically reduced during winemaking then during aging. Yeast and lactic acid bacteria were also isolated
from very old vintages. B. bruxellensis and O. oeni were the most frequent. 相似文献
179.
Maria Florencia Tellechea Flvia S. Donaires Vinícius S. de Carvalho Brbara A. Santana Fernanda B. da Silva Raissa S. Tristo Lílian F. Moreira Aline F. de Souza Yordanka M. Armenteros Lygia V. Pereira Rodrigo T. Calado 《Cell death & disease》2022,13(4)
In acquired immune aplastic anemia (AA), pathogenic cytotoxic Th1 cells are activated and expanded, driving an immune response against the hematopoietic stem and progenitor cells (HSPCs) that provokes cell depletion and causes bone marrow failure. However, additional HSPC defects may contribute to hematopoietic failure, reflecting on disease outcomes and response to immunosuppression. Here we derived induced pluripotent stem cells (iPSCs) from peripheral blood (PB) erythroblasts obtained from patients diagnosed with immune AA using non-integrating plasmids to model the disease. Erythroblasts were harvested after hematologic response to immunosuppression was achieved. Patients were screened for germline pathogenic variants in bone marrow failure-related genes and no variant was identified. Reprogramming was equally successful for erythroblasts collected from the three immune AA patients and the three healthy subjects. However, the hematopoietic differentiation potential of AA-iPSCs was significantly reduced both quantitatively and qualitatively as compared to healthy-iPSCs, reliably recapitulating disease: differentiation appeared to be more severely affected in cells from the two patients with partial response as compared to the one patient with complete response. Telomere elongation and the telomerase machinery were preserved during reprogramming and differentiation in all AA-iPSCs. Our results indicate that iPSCs are a reliable platform to model immune AA and recapitulate clinical phenotypes. We propose that the immune attack may cause specific epigenetic changes in the HSPCs that limit adequate proliferation and differentiation.Subject terms: Anaemia, Induced pluripotent stem cells 相似文献
180.
Aline Vieira Santos Anna Carina Antunes e Defaveri Humberto Ribeiro Bizzo Rosane Aguiar da Silva San Gil Alice Sato 《In vitro cellular & developmental biology. Plant》2013,49(4):405-413
Varronia curassavica is cultivated for the production of an essential oil useful in the pharmaceutical industry for its strong anti-inflammatory effect. Despite a growing demand, only a few studies have evaluated alternative sources of obtaining plantlets or ways to increase the yield of essential oil from this species. Therefore, this study aimed to optimize the in vitro multiplication rate and analyze the histochemistry and sesquiterpene production potential of conventionally propagated V. curassavica plants, in vitro shoots, and acclimatized plants derived from in vitro shoots. For axillary bud proliferation, Murashige and Skoog medium was supplemented with 6-benzyladenine and thidiazuron alone or in combination with naphthalene acetic acid. Axillary bud proliferation was obtained from culture of nodal or apical segments on medium containing half-strength Murashige and Skoog salts without growth regulators. After 35 d of culture, an average of five buds developed per explant. Elongation and rooting of shoots also occurred in this medium. After the transfer of rooted plants to ex vitro conditions, 100% of the plantlets survived. Histochemical analysis of leaf tissue showed the presence of lipids, acidic lipids, essential oil, phenols, and flavonoids. The essential oils from conventionally propagated and acclimatized plants were extracted by hydrodistillation and analyzed using gas chromatography. The essential oil from acclimatized plants had a similar profile to that from ex vitro plants, but with a higher concentration of the anti-inflammatory compound alpha-humulene. 相似文献