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81.
Questions
What are the most important drivers of plant species richness (gamma‐diversity) and species turnover (beta‐diversity) in the field layer of a forest edge? Does the tree and shrub species richness structure and complexity affect the richness of forest and grassland specialist species?Location
Southeast Sweden.Methods
We sampled 50 forest edges with different levels of structural complexity in agricultural landscapes. In each border we recorded trees, shrubs and herb layer species in a 50‐m transect parallel with the forest. We investigated species composition and species turnover in relation to the proportions of gaps in the border and the diversity of trees and shrubs.Results
Total plant species richness in the field layer was mainly explained by the proportion of gaps to areas with full canopy cover and tree diversity. Increasing number of gaps promoted higher diversity of grassland specialist species within the field layer, resulting in open forest borders with the highest overall species richness. Gaps did however have a negative impact on forest species richness. Conversely, increasing forest species richness was positively related to tree diversity, but the number of grassland specialist species was negatively affected by tree diversity.Conclusions
Managing forest borders, and therefore increasing the area of semi‐open habitats in fragmented agricultural landscapes, provides future opportunities to create a network of suitable habitats for both grassland and deciduous forest specialist species. Such measures therefore have the potential to increase functional connectivity and support dispersal of species in homogeneous forest/agricultural landscapes. 相似文献82.
Combination of Multiplex PCR and PCR-Denaturing Gradient Gel Electrophoresis for Monitoring Common Sourdough-Associated Lactobacillus Species 下载免费PDF全文
Luca Settanni Sara Valmorri Douwe van Sinderen Giovanna Suzzi Antonello Paparella Aldo Corsetti 《Applied microbiology》2006,72(5):3793-3796
A combination of denaturing gradient gel electrophoresis (DGGE) and a previously described multiplex PCR approach was employed to detect sourdough lactobacilli. Primers specific for certain groups of Lactobacillus spp. were used to amplify fragments, which were analyzed by DGGE. DGGE profiles obtained from Lactobacillus type strains acted as standards to analyze lactobacilli from four regional Abruzzo (central Italy) sourdoughs. 相似文献
83.
Fariba Rezaee Samantha A. DeSando Andrei I. Ivanov Timothy J. Chapman Sara A. Knowlden Lisa A. Beck Steve N. Georas 《Journal of virology》2013,87(20):11088-11095
Understanding the regulation of airway epithelial barrier function is a new frontier in asthma and respiratory viral infections. Despite recent progress, little is known about how respiratory syncytial virus (RSV) acts at mucosal sites, and very little is known about its ability to influence airway epithelial barrier function. Here, we studied the effect of RSV infection on the airway epithelial barrier using model epithelia. 16HBE14o- bronchial epithelial cells were grown on Transwell inserts and infected with RSV strain A2. We analyzed (i) epithelial apical junction complex (AJC) function, measuring transepithelial electrical resistance (TEER) and permeability to fluorescein isothiocyanate (FITC)-conjugated dextran, and (ii) AJC structure using immunofluorescent staining. Cells were pretreated or not with protein kinase D (PKD) inhibitors. UV-irradiated RSV served as a negative control. RSV infection led to a significant reduction in TEER and increase in permeability. Additionally it caused disruption of the AJC and remodeling of the apical actin cytoskeleton. Pretreatment with two structurally unrelated PKD inhibitors markedly attenuated RSV-induced effects. RSV induced phosphorylation of the actin binding protein cortactin in a PKD-dependent manner. UV-inactivated RSV had no effect on AJC function or structure. Our results suggest that RSV-induced airway epithelial barrier disruption involves PKD-dependent actin cytoskeletal remodeling, possibly dependent on cortactin activation. Defining the mechanisms by which RSV disrupts epithelial structure and function should enhance our understanding of the association between respiratory viral infections, airway inflammation, and allergen sensitization. Impaired barrier function may open a potential new therapeutic target for RSV-mediated lung diseases. 相似文献
84.
Sara Cooper 《Culture, medicine and psychiatry》2016,40(3):307-337
A strong movement has emerged recently which is highlighting the high levels of untreated mental illness in Africa and making proposals for reducing this ‘gap’ in mental health care. This movement has been criticised for insufficiently attending to the epistemologies embedded in its recommendations, and inadequately considering the views of practitioners ‘on the ground’. Employing a narrative-based approach, I accessed the stories about the mental health ‘treatment gap’ of 28 psychiatrists all working clinically in public mental health care settings in South Africa, Uganda, Nigeria or Ethiopia. Rather than focusing on the content of these stories, I was more interested in their underpinning meaning-codes and epistemological politics. Dominant thinking about the ‘treatment gap’ was heavily informed by a biomedical paradigm, and associated epistemological order of European Colonial Modernity. There were, however, cracks in this master narrative, which crystalised in the stories that were told by three particular psychiatrists. Their narratives operated within an alternative paradigm, one which appears to be informed by the tradition of phenomenology, and in particular the ideas associated with French philosopher Merleau-Ponty. This more marginalised thinking may offer important insights into reducing the mental health ‘treatment gap’ in Africa in ways very different from those created by current seats of power. 相似文献
85.
86.
Rapid In Situ Assay for Indoleacetic Acid Production by Bacteria Immobilized on a Nitrocellulose Membrane 总被引:6,自引:2,他引:6 下载免费PDF全文
We have developed a new assay that differentiates between indoleacetic acid (IAA)-producing and -nonproducing bacteria on a colony plate lift. Medium supplemented with 5 mM L-tryptophan is inoculated with isolates of interest, overlaid with a nitrocellulose membrane, and then incubated until bacterial colonies reach 1 to 2 mm in diameter. The membrane is removed to a filter paper saturated with Salkowski reagent and incubated until distinct red haloes form around the colonies. The colorimetric reaction to IAA is limited to a region immediately surrounding each colony, is specific to isolates producing IAA, occurs within 1 h after the membrane is placed in the reagent, and is sensitive to as little as 50 pmol of IAA in a 2-mm2 spot. We have used this assay for quantifying epiphytic and endophytic populations of IAA-producing isolates of Pseudomonas syringae subsp. savastanoi and for detecting IAA-producing colonies of other pseudomonads and Erwinia herbicola. The assay provides a rapid and convenient method to screen large numbers of bacteria. 相似文献
87.
88.
Anatomy of the antennal dorsal organ in female of Neodryinus typhlocybae (Hymenoptera: Dryinidae): A peculiar sensory structure possibly involved in perception of host vibration 下载免费PDF全文
Paola Riolo Nunzio Isidoro Sara Ruschioni Roxana L. Minuz Ferdinando Bin Roberto Romani 《Journal of morphology》2016,277(1):128-137
Neodryinus typhlocybae (Hymenoptera: Dryinidae) is a natural enemy of the planthopper Metcalfa pruinosa, which was introduced from North America into Europe and has become established in various regions as a pest species. Vibrational signals play a crucial role in the communication of M. pruinosa, which appears to be exploited by N. typhlocybae. Scanning and transmission electron microscopy have shown that the antennae of N. typhlocybae females have peculiar and complex sensory structures: deep longitudinal grooves that house long sensilla trichodea, termed here “Antennal Dorsal Organs.” Such structures were not present on male antennae. These sensilla extend for the length of the grooves, without contact with the groove cuticle. Their hair shaft is empty and aporous, and inserted into a specialized socket, underneath which there is a cuticular ampulla‐like chamber. Each sensillum is associated with two sensory neurons: one terminates at the proximal end of the dendritic sheath; the other continues into the sensillum sinus and is enclosed in the dendritic sheath. This second sensory neuron then enters the ampulla‐like chamber through the circular opening, and then terminates with a conspicuous tubular body at the shaft base. The possible involvement of this peculiar structure in the context of host recognition mechanism is discussed. J. Morphol. 277:128–137, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
89.
Ventura Luigi Gnetti Letizia Rossi Maurizio Tiseo Marcello Giordano Giovanna Corradi Massimo Silva Mario Milanese Gianluca Minari Roberta Leonetti Alessandro Cattadori Sara Ampollini Luca Carbognani Paolo Mozzoni Paola 《Molecular biology reports》2021,48(4):3485-3494
Molecular Biology Reports - Benign metastasizing leiomyoma (BML) is a rare disease characterized by extrauterine benign leiomyomatosis in patients with a previous or concomitant history of uterine... 相似文献
90.
Engineering grapevine for increased resistance to fungal pathogens without compromising wine stability 总被引:3,自引:0,他引:3
The vast majority of wine proteins have recently been identified as pathogenesis-related (PR) proteins. During the growing season, these proteins are expressed in developmentally dependent and inducible manners in grapevine leaves and grape berries, in which they are believed to play an important role in protection against fungal pathogens and possibly other stresses. Because of their inherent resistance to proteolytic attack and to the low pH values characteristic of wines, vinification can be seen as a "purification strategy" for grape PR proteins. The inevitable consequent accumulation of these proteins in wines becomes a technological nuisance because they adversely affect the clarity and stability of wines. Genetically modified vines underexpressing PR proteins would certainly lead to stable wines but would increase the plant susceptibility to fungal attack, and the actual trend seems to be in the opposite direction, that is overexpressing these proteins to obtain plants with enhanced resistance to pathogens--a trend that will probably augment problems associated with protein instability in the resulting wines. 相似文献