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141.
Morphophysiological and Biochemical Responses of Lippia grata Schauer (Verbenaceae) to Water Deficit
Palhares Neto Luiz de Souza Lindomar Maria de Morais Marciana Bizerra Arruda Emília de Figueiredo Regina Célia Bressan Queiroz de Albuquerque Cynthia Cavalcanti Ulisses Cláudia 《Journal of Plant Growth Regulation》2020,39(1):26-40
Journal of Plant Growth Regulation - In the present study, we investigated the morphophysiological and biochemical responses of the species Lippia grata Schauer to water deficit. Plants from... 相似文献
142.
Marissa J. Maroni Kimberly M. Capri Nicole L. Arruda Rachel R. Gelineau Hannah V. Deane Holly A. Concepcion 《Chronobiology international》2020,37(6):809-823
ABSTRACT Altered circadian rhythms have negative consequences on health and behavior. Emerging evidence suggests genetics influences the physiological and behavioral responses to circadian disruption. We investigated the effects of a 21 h day (T = 21 cycle), with high-fat diet consumption, on locomotor activity, explorative behaviors, and health in male C57BL/6J and C57BL/6N mice. Mice were exposed to either a T = 24 or T = 21 cycle and given standard rodent chow (RC) or a 60% high-fat diet (HFD) followed by behavioral assays and physiological measures. We uncovered numerous strain differences within the behavioral and physiological assays, mainly that C57BL/6J mice exhibit reduced susceptibility to the obesogenic effects of (HFD) and anxiety-like behavior as well as increased circadian and novelty-induced locomotor activity compared to C57BL/6N mice. There were also substrain-specific differences in behavioral responses to the T = 21 cycle, including exploratory behaviors and circadian locomotor activity. Under the 21-h day, mice consuming RC displayed entrainment, while mice exposed to HFD exhibited a lengthening of activity rhythms. In the open-field and light-dark box, mice exposed to the T = 21 cycle had increased novelty-induced locomotor activity with no further effects of diet, suggesting daylength may affect mood-related behaviors. These results indicate that different circadian cycles impact metabolic and behavioral responses depending on genetic background, and despite circadian entrainment. 相似文献
143.
Juliana Maria Costa Nuñez Jessica Mie Ferreira Koyama Takahashi Guilherme Elias Pessanha Henriques Mauro Antônio de Arruda Nóbilo Rafael Leonardo Xediek Consani Marcelo Ferraz Mesquita 《Gerodontology》2011,28(3):233-237
Radiographic inspection of porosity in pure titanium dumbbell castings Background: Titanium frameworks are frequently indicated for implant supported prostheses; however, voids are usually encountered inside cast titanium. Objective: This study aimed to confirm the efficacy of a radiographic technique for inspection of porosity in commercially pure titanium castings with different diameter. Materials and methods: Sixty dumbbell rods (n = 20) with a central 1.5, 2.0 and 3.5 mm diameter were prepared by lost‐wax casting. Cast specimens were finished and polished and submitted to radiographic examination (90 kV, 15 mA, 0.6 s and 10–13 mm of distance) using periapical film. The radiographs were visually analysed for the presence of porosity in the extension of the dumbbell or in the central portion of the rods. Data were submitted to Pearson Chi‐square test (5%). Results: The tested radiographic method proved to be suitable for the evaluation of cast frameworks. Internal porosities were observed in most of the specimens (91.7%) (p = 0.0005); however, only 20% occurred on the central portion of the rods (p = 0.612). Conclusion: Internal porosities can be visualised through radiographs and occur mostly in small diameter structures. The radiographic evaluation of metal structures can improve the quality of frameworks and thereby potentially increase the longevity of the rehabilitation. 相似文献
144.
Genome sequence of the diazotrophic Gram-positive rhizobacterium Paenibacillus riograndensis SBR5(T)
Beneduzi A Campos S Ambrosini A de Souza R Granada C Costa P Arruda L Moreira F Vargas LK Weiss V Tieppo E Faoro H de Souza EM Pedrosa FO Passaglia LM 《Journal of bacteriology》2011,193(22):6391-6392
Paenibacillus riograndensis SBR5(T), a nitrogen-fixing Gram-positive rhizobacterium isolated from a wheat field in the south of Brazil, has a great potential for agricultural applications due to its plant growth promotion effects. Here we present the draft genome sequence of P. riograndensis SBR5(T). Its 7.37-Mb genome encodes determinants of the diazotrophic lifestyle and plant growth promotion, such as nitrogen fixation, antibiotic resistance, nitrate utilization, and iron uptake. 相似文献
145.
Jorge RS Ferreira F Ferreira Neto JS Vasconcellos Sde A Lima Ede S Morais ZM Souza GO 《Memórias do Instituto Oswaldo Cruz》2011,106(4):441-444
Leptospirosis is a zoonotic disease affecting most mammals and is distributed throughout the world. Several species of domestic and wild animals may act as reservoirs for this disease. The purpose of this study was to assess the exposure of free-ranging wild carnivores, horses and domestic dogs on a private reserve located in the northern Pantanal (Brazil) and the surrounding areas to Leptospira spp from 2002-2006, 75 free-ranging wild carnivores were captured in the Pantanal and serum samples were collected. In addition, samples from 103 domestic dogs and 23 horses in the region were collected. Serum samples were tested for the presence of Leptospira antibodies using the microscopic agglutination test. Thirty-two wild carnivores (42.7%) were considered positive with titres ≥ 100, and 18 domestic dogs (17.5%) and 20 horses (74.1%) were also found to be positive. Our study showed that horses, dogs and several species of free-ranging wild carnivores have been exposed to Leptospira spp in the Pantanal, suggesting that the peculiar characteristics of this biome, such as high temperatures and an extended period of flooding, may favour bacterial persistence and transmission. In this region, wild carnivores and horses seem to be important hosts for the epidemiology of Leptospira species. 相似文献
146.
Fernandes MC Andrade LR Andrews NW Mortara RA 《Memórias do Instituto Oswaldo Cruz》2011,106(8):1014-1016
It has been recently shown that Trypanosoma cruzi trypomastigotes subvert a constitutive membrane repair mechanism to invade HeLa cells. Using a membrane extraction protocol and high-resolution microscopy, the HeLa cytoskeleton and T. cruzi parasites were imaged during the invasion process after 15 min and 45 min. Parasites were initially found under cells and were later observed in the cytoplasm. At later stages, parasite-driven protrusions with parallel filaments were observed, with trypomastigotes at their tips. We conclude that T. cruzi trypomastigotes induce deformations of the cortical actin cytoskeleton shortly after invasion, leading to the formation of pseudopod-like structures. 相似文献
147.
Campos RA Arruda W Boldo JT da Silva MV de Barros NM de Azevedo JL Schrank A Vainstein MH 《Current microbiology》2005,50(5):257-261
Beauveria bassiana is a well-known broad-range arthropod pathogen which has been used in biological control of several pest insects and ticks such as Boophilus microplus. Beauveria amorpha has both endophytic and entomopathogenic characteristics, but its capacity for biological control has still not been studied. During the processes of host infection, B. bassiana and B. amorpha produce several hydrolytic extracellular enzymes, including proteases and chitinases, which probably degrade the host cuticle and are suggested to be pathogenicity determinants. To access the role of these enzymes during infection in the tick B. microplus, we analyzed their secretion during fungus growth in single and combined carbon sources, compared to complex substrates such as chitin and B. microplus cuticle. Chitin and tick cuticle-induced chitinase in both fungus and protease was induced only by tick cuticle. SEM analysis of B. amorpha and B. bassiana infecting B. microplus showed apressorium formation during penetration on cattle tick cuticle. 相似文献
148.
Singh AK Patel J Litbarg NO Gudehithlu KP Sethupathi P Arruda JA Dunea G 《Cell and tissue research》2008,332(1):81-88
When rat omentum becomes activated by intraperitoneal injection of inert polydextran particles, these particles are rapidly
surrounded by cells that express markers of adult stem cells (SDF–1α, CXCR4, WT–1) and of embryonic pluripotent cells (Oct–4,
Nanog, SSEA–1). We have cultured such cells, because they may offer a convenient source of adult stem cells, and have found
that they retain stem cell markers and produce high levels of vascular endothelial growth factor for up to ten passages. After
systemic or local injection of these cultured cells into rats with acute injury of various organs, the cells specifically
engraft at the injured sites. Thus, our experiments show that omental stromal cells can be cultured from activated omentum,
and that these cells exhibit stem cell properties enabling them to be used for repair and possibly for the regeneration of
damaged tissues. 相似文献
149.
Calich VL da Costa TA Felonato M Arruda C Bernardino S Loures FV Ribeiro LR de Cássia Valente-Ferreira R Pina A 《Mycopathologia》2008,165(4-5):223-236
Innate immunity is based in pre-existing elements of the immune system that directly interact with all types of microbes leading
to their destruction or growth inhibition. Several elements of this early defense mechanism act in concert to control initial
pathogen growth and have profound effect on the adaptative immune response that further develops. Although most studies in
paracoccidioidomycosis have been dedicated to understand cellular and humoral immune responses, innate immunity remains poorly
defined. Hence, the main purpose of this review is to present and discuss some mechanisms of innate immunity developed by
resistant and susceptible mice to Paracoccidioides brasiliensis infection, trying to understand how this initial host-pathogen interface interferes with the protective or deleterious adaptative
immune response that will dictate disease outcome. An analysis of some mechanisms and mediators of innate immunity such as
the activation of complement proteins, the microbicidal activity of natural killer cells and phagocytes, the production of
inflammatory eicosanoids, cytokines, and chemokines among others, is presented trying to show the important role played by
innate immunity in the host response to P. brasiliensis infection. 相似文献
150.
Activated omentum becomes rich in factors that promote healing and tissue regeneration 总被引:3,自引:0,他引:3
Litbarg NO Gudehithlu KP Sethupathi P Arruda JA Dunea G Singh AK 《Cell and tissue research》2007,328(3):487-497
In order to study the mechanism by which an omental pedicle promotes healing when applied to an injured site, we injected
a foreign body into the abdominal cavity to activate the omentum. One week after the injection, we isolated the omentum and
measured blood vessel density, blood content, growth and angiogenesis factors (VEGF and others), chemotactic factors (SDF-1α),
and progenitor cells (CXCR-4, WT-1). We found that the native omentum, which consisted mostly of adipose tissue, expanded
the mass of its non-adipose part (milky spots) 15– to 20-fold. VEGF and other growth factors increased by two– to four-fold,
blood vessel density by three-fold, and blood content by two-fold. The activated omentum also showed increases in SDF-1α,
CXCR-4, and WT-1 cells (factors and cells positively associated with tissue regeneration). Thus, we propose that an omentum
activated by a foreign body (or by injury) greatly expands its milky-spot tissue and becomes rich in growth factors and progenitor
cells that facilitate the healing and regeneration of injured tissue.
This work was partly supported by a grant (no. 2000–241 to A.K.S.) from the Juvenile Diabetes Foundation International. 相似文献