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221.
222.
James Skelton Michelle A. Jusino Paige S. Carlson Katherine Smith Mark T. Banik Daniel L. Lindner Jonathan M. Palmer Jiri Hulcr 《Molecular ecology》2019,28(22):4971-4986
A prevailing paradigm in forest ecology is that wood‐boring beetles facilitate wood decay and carbon cycling, but empirical tests have yielded mixed results. We experimentally determined the effects of wood borers on fungal community assembly and wood decay within pine trunks in the southeastern United States. Pine trunks were made either beetle‐accessible or inaccessible. Fungal communities were compared using culturing and high‐throughput amplicon sequencing (HTAS) of DNA and RNA. Prior to beetle infestation, living pines had diverse fungal endophyte communities. Endophytes were displaced by beetle‐associated fungi in beetle‐accessible trees, whereas some endophytes persisted as saprotrophs in beetle‐excluded trees. Beetles increased fungal diversity several fold. Over forty taxa of Ascomycota were significantly associated with beetles, but beetles were not consistently associated with any known wood‐decaying fungi. Instead, increasing ambrosia beetle infestations caused reduced decay, consistent with previous in vitro experiments that showed beetle‐associated fungi reduce decay rates by competing with decay fungi. No effect of bark‐inhabiting beetles on decay was detected. Platypodines carried significantly more fungal taxa than scolytines. Molecular results were validated by synthetic and biological mock communities and were consistent across methodologies. RNA sequencing confirmed that beetle‐associated fungi were biologically active in the wood. Metabarcode sequencing of the LSU/28S marker recovered important fungal symbionts that were missed by ITS2, though community‐level effects were similar between markers. In contrast to the current paradigm, our results indicate ambrosia beetles introduce diverse fungal communities that do not extensively decay wood, but instead reduce decay rates by competing with wood decay fungi. 相似文献
223.
Sophie-Marie Aicher Felix Streicher Maxime Chazal Delphine Planas Dongsheng Luo Julian Buchrieser Monika Nemcova Veronika Seidlova Jan Zukal Jordi Serra-Cobo Dominique Pontier Bertrand Pain Gert Zimmer Olivier Schwartz Philippe Roingeard Jiri Pikula Laurent Dacheux Nolwenn Jouvenet 《Journal of virology》2022,96(14)
224.
225.
Metabolism of polychlorinated biphenyls by Solanum nigrum hairy root clone SNC-9O and analysis of transformation products 总被引:1,自引:0,他引:1
Kučerová Petra Macková Martina Chromá Ludmila Burkhard Jiri Tríska Jan Demnerová Katerina Macek Tomáš 《Plant and Soil》2000,225(1-2):109-115
The study investigates aspects of PCB metabolism by a hairy root culture of Solanum nigrum L. (clone SNC-9O) in vitro. Standard conditions were established for efficient, up to 72% PCB conversion (22 individual PCB congeners examined in commercial
mixture Delor 103, 5 g fresh biomass in 100 ml media shaken with 5 mg PCB for 14 days). The conversion products formed from
three monochlorobiphenyls were monohydroxychlorobiphenyls and dihydroxychlorobiphenyls, while six dichlorobiphenyls yielded
different monohydroxydichlorobiphenyls. Efficiency of the transformation of individual PCB congeners was evaluated together
with phytotoxic effect on the clone SNC-9O. Major metabolites of monochlorobiphenyls analysed after extraction from biomass
were hydroxylated at the position 4, and 4′, respectively.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
226.
Martin Konvicka Jan Novak Jiri Benes Zdenek Fric Jonathan Bradley Petr Keil Jan Hrcek Karel Chobot Pavel Marhoul 《Journal of Insect Conservation》2008,12(5):549-560
The distribution of Lopinga achine (Lepidoptera Nymphalidae, Satyrinae) in the Czech Republic has declined from thirty grid squares before 1950 to just one extant population,
restricted to a single area of deciduous woodland. A review of historical sites shows that this species used to occur in various
types of deciduous woodland with a relatively sparse canopy maintained by coppicing and/or grazing. The extant population
inhabits mature woodland with a mean canopy cover of 60% (quartiles 50% and 65%), sparse shrubs and a species-rich herb layer
containing plant species requiring dry, warm and nutrient-poor conditions. The larval host plants are the fine-leafed sedges,
Carex fritschii and C. michelii. In 2006, the total population contained about 10,000 adults but this may be an over-estimate, biased by male behaviour.
Measurements of adult mobility, well approximated by an inverse-power function, suggested that all existing colonies are interconnected
by dispersal. Continuing existence of the population depends on two conditions; nutrient-poor conditions for a diverse ground
flora and a sparse tree canopy. While canopy closure is gradually increasing, the herb layer is threatened by soil enrichment
due to the demise of traditional grazing, litter raking and grass mowing in woodlands. Any future management to favour Lopinga achine should include both measures to maintain a sparse canopy and measures to export biomass, such as raking or mowing of ground
flora or, preferably, re-establishment of grazing.
An erratum to this article can be found at 相似文献
227.
Filippo Favilli Michal Bíl Jiri Sedoník Richard Andrášik Peter Kasal Andreas Agreiter Thomas Streifeneder 《European Journal of Wildlife Research》2018,64(5):59
This paper is the first dealing with animal-vehicle collisions (AVC) with red and roe deer in South Tyrol, Northern Italy. The Autonomous Province of Bolzano (South Tyrol) has been collecting AVC data since 2012 on the entire provincial road network. Each year, AVC data accounted for more than 700 cases per year, with several socioeconomic and ecological implications. The aim of this research is to identify the locations where AVC occur more frequently than expected (hotspots) and better outline subsequent implementation of mitigation measures. For an effective identification of AVC hotspots, we applied a combined methodology of temporal and spatial analysis on AVC data collected on the South Tyrol road network in the years 2012–2014. AVC data enabled the identification of the temporal patterns, which showed different behaviors of the two target species in close proximity of the road network and throughout the 12 months. The KDE+ software applied to the 2012–2014 AVC database allowed for spatial analysis and the identification of hotspots, i.e., the road sections having the highest risk for drivers. The integration of the results, coming from the abovementioned methodologies, contributes to a detailed assessment of roads that would allow the identification of the local contributing factors and a base-line of potential problematic areas that will highlight the need for further investigation to assess whether the risk-rank is accurate and allocate effectively limited resources to a feasible number of identified hotspots and reduce the current degree of AVC in the South Tyrolean road network. 相似文献
228.
Miroslava Chalupova Anna Skalova Tomas Hajek Lenka Geigerova Dana Kralova Pavel Liska Hana Hecova Jiri Molacek Jaroslav Hrabak 《Folia microbiologica》2018,63(6):707-711
Nowadays, dental diseases are one of the most common illnesses in the world. Some of them can lead to translocation of oral bacteria to the bloodstream causing intermittent bacteraemia. Therefore, a potential association between oral infection and cardiovascular diseases has been discussed in recent years as a result of adhesion of oral microbes to the heart valves. The aim of this study was to detect oral bacteria on pathologically changed heart valves not caused by infective endocarditis. In the study, patients with pathologically changed heart valves were involved. Samples of heart valves removed during heart valve replacement surgery were cut into two parts. One aliquot was cultivated aerobically and anaerobically. Bacterial DNA was extracted using Ultra-Deep Microbiome Prep (Molzym GmbH, Bremen, Germany) followed by a 16S rRNA gene PCR amplification using Mastermix 16S Complete kit (Molzym GmbH, Bremen, Germany). Positive PCR products were sequenced and the sequences were analyzed using BLAST database (http://www.ncbi.nlm.nih/BLAST). During the study period, 41 samples were processed. Bacterial DNA of the following bacteria was detected in 21 samples: Cutibacterium acnes (formerly Propionibacterium acnes) (n?=?11; 52.38% of patients with positive bacterial DNA detection), Staphylococcus sp. (n?=?9; 42.86%), Streptococcus sp. (n?=?1; 4.76%), Streptococcus sanguinis (n?=?4; 19.05%), Streptococcus oralis (n?=?1; 4.76%), Carnobacterium sp. (n?=?1; 4.76%), Bacillus sp. (n?=?2; 9.52%), and Bergeyella sp. (n?=?1; 4.76%). In nine samples, multiple bacteria were found. Our results showed significant appearance of bacteria on pathologically changed heart valves in patients with no symptoms of infective endocarditis. 相似文献
229.
Judith M. Ball Zina Moldoveanu Lawrence R. Melsen Pamela A. Kozlowski Susan Jackson Mark J. Mulligan Jiri F. Mestecky Richard W. Compans 《In vitro cellular & developmental biology. Animal》1995,31(3):196-206
Summary We have demonstrated that a human endometrial cell line, HEC-1, maintains a high transepithelial electrical resistance, directionally
transports fluids across the cell monolayer, and releases enveloped viruses at distinct plasma membrane domains: influenza
virus is released at the apical surfaces and vesicular stomatitis virus (VSV) at the basolateral surfaces. In addition, we
have examined the expression of domain-specific endogenous proteins, including the polyimmunoglobulin receptor. Multiple endogenous
polypeptides were found to be secreted into the culture medium at basolateral surfaces, whereas no secretion of specific polypeptides
was observed from apical cell surfaces. Distinct patterns of endogenous proteins were also observed on apical and basolateral
cell surfaces, with a much more complex polypeptide pattern on the basolateral membranes. Using surface biotinylation and
immunofluorescence, the polyimmunoglobulin receptor was found to be expressed on the basolateral surfaces of HEC-1 monolayers.
The specific binding of poly-immunoglobulin A (pIgA) was found to occur on the basolateral surface, and was followed by transcytosis
to the apical surface and release into the apical medium. The observed characteristics indicate that the endometrium-derived
HEC-1 epithelial cell line can be employed as a model for studies of protein transport in polarized epithelial cells of human
endometrial tissues, as well as for studies of the interaction of microorganisms with epithelial cells in the genital tract. 相似文献
230.
Ales Macela Jiri Stulik Lenka Hernychova Michal Kroca Zuzana Krocova Hana Kovarova 《FEMS immunology and medical microbiology》1996,13(3):235-238
Abstract The impact of Lps gene on the course of immune response against subcutaneous infection of mice with Francisella tularensis live vaccine strain was studied. Production and specificity of antibodies, cytotoxic responses of macrophages and NK-cells, spontaneous production ex vivo of cytokines IL-1α, IL-2, IL-4, IL-6, IL-10, IFN-γ, and TNF-α in spleen cell cultures in C3H/HeJ ( Lps d ) mice in comparison with C3H/HeN ( Lps r ) mice were tested. The value of LD50 was significantly different in the two strains of mice (8.0 × 103 cfu for C3H/HeJ versus 4.61 × 105 cfu for C3H/HeN mice after subcutaneous inoculation). The production of NO2 is also impaired in C3H/HeJ mice in the early intervals after infection. Thus, the defective Lps gene of C3H/HeJ mice influences both the level of innate resistance of mice to F. tularensis live vaccine strain infection and the process of induction and regulation of immune response against this intracellular bacterial pathogen. 相似文献