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991.
Suzana Vieira Rabêlo Fernanda Granja da Silva Oliveira Michele Miriam Calixto de Lira Livia Macedo Dutra Adilson Sartoratto Marta Cristina Teixeira Duarte Maria Claudia dos Santos Luciano Maria Francilene Souza Silva Cláudia do Ó Pessoa Manoel Odorico de Moraes Filho Emmanoel Vilaça Costa Jackson Roberto Guedes da Silva Almeida 《Phyton》2021,90(3):921-931
This study aimed to identify the chemical composition of essential oil from fruits (EOAF) and the hexanic crude
extract from aerial parts (At-Hex) of atemoya (Annona cherimola x Annona squamosa), a hybrid belonging to the
Annonaceae family. Cytotoxic and antimicrobial activity was also evaluated. OEAF was obtained by hydrodistillation using a Clevenger apparatus, and their composition was analyzed by gas chromatography-mass spectrometry
(GC-MS) analyses. Cytotoxicity was tested against human tumor cell lines HCT-116 (colon carcinoma), SF-295
(glioblastoma), OVCAR-8 (ovarian carcinoma) and HL60 (leukemia) using 3-(4,5-dimethyl-2-thiazolyl)-2,5-
diphenyl-2H-tetrazolium bromide (MTT) assay, while antimicrobial activity was conducted by bioauthography
method against eleven microorganisms strains. Twenty-four compounds were identified in the EOAF and
twenty-nine in At-Hex. The monoterpenes linalool (25.70%), α-pinene (10.38%), β-pinene (9.12%), transocimene (7.43%), and the sesquiterpene bicyclogermacrene (12.58%) were the major constituents of EOAF,
whereas the sesquiterpene spathulenol (13.91%) was the main compound of At-Hex. At-Hex showed a high
cytotoxicity against SF-295 (glioblastoma). These findings show an important chemotaxonomic contribution
for the Annonaceae family, mainly for the Annona genus. Atemoya proved to be a promising source of substances
with potential cytotoxic activity. 相似文献
992.
993.
Joyce M Ngoi Peter K Quashie Collins M Morang'a Joseph HK Bonney Dominic SY Amuzu Selassie Kumordjie Ivy A Asante Evelyn Y Bonney Miriam Eshun Linda Boatemaa Vanessa Magnusen Erasmus N Kotey Nicaise T Ndam Frederick Tei-Maya Augustina K Arjarquah Evangeline Obodai Isaac D Otchere Yaw Bediako Joe K Mutungi Lucas N Amenga-Etego John K Odoom Abraham K Anang George B Kyei Bright Adu William K Ampofo Gordon A Awandare 《Experimental biology and medicine (Maywood, N.J.)》2021,246(8):960
The confirmed case fatality rate for the coronavirus disease 2019 (COVID-19) in Ghana has dropped from a peak of 2% in March to be consistently below 1% since May 2020. Globally, case fatality rates have been linked to the strains/clades of circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within a specific country. Here we present 46 whole genomes of SARS-CoV-2 circulating in Ghana, from two separate sequencing batches: 15 isolates from the early epidemic (March 12–April 1 2020) and 31 from later time-points ( 25–27 May 2020). Sequencing was carried out on an Illumina MiSeq system following an amplicon-based enrichment for SARS-CoV-2 cDNA. After genome assembly and quality control processes, phylogenetic analysis showed that the first batch of 15 genomes clustered into five clades: 19A, 19B, 20A, 20B, and 20C, whereas the second batch of 31 genomes clustered to only three clades 19B, 20A, and 20B. The imported cases (6/46) mapped to circulating viruses in their countries of origin, namely, India, Hungary, Norway, the United Kingdom, and the United States of America. All genomes mapped to the original Wuhan strain with high similarity (99.5–99.8%). All imported strains mapped to the European superclade A, whereas 5/9 locally infected individuals harbored the B4 clade, from the East Asian superclade B. Ghana appears to have 19B and 20B as the two largest circulating clades based on our sequence analyses. In line with global reports, the D614G linked viruses seem to be predominating. Comparison of Ghanaian SARS-CoV-2 genomes with global genomes indicates that Ghanaian strains have not diverged significantly from circulating strains commonly imported into Africa. The low level of diversity in our genomes may indicate lower levels of transmission, even for D614G viruses, which is consistent with the relatively low levels of infection reported in Ghana. 相似文献
994.
Cristina Morsiani Lucia TerleckiZaniewicz Susanna Skalicky Maria Giulia Bacalini Salvatore Collura Maria Conte Federica Sevini Paolo Garagnani Stefano Salvioli Matthias Hackl Johannes Grillari Claudio Franceschi Miriam Capri 《Aging cell》2021,20(7)
Blood circulating microRNAs (c‐miRs) are potential biomarkers to trace aging and longevity trajectories to identify molecular targets for anti‐aging therapies. Based on a cross‐sectional study, a discovery phase was performed on 12 donors divided into four groups: young, old, healthy, and unhealthy centenarians. The identification of healthy and unhealthy phenotype was based on cognitive performance and capabilities to perform daily activities. Small RNA sequencing identified 79 differentially expressed c‐miRs when comparing young, old, healthy centenarians, and unhealthy centenarians. Two miRs, that is, miR‐19a‐3p and miR‐19b‐3p, were found increased at old age but decreased at extreme age, as confirmed by RT‐qPCR in 49 donors of validation phase. The significant decrease of those miR levels in healthy compared to unhealthy centenarians appears to be due to the presence of isomiRs, not detectable with RT‐qPCR, but only with a high‐resolution technique such as deep sequencing. Bioinformatically, three main common targets of miR‐19a/b‐3p were identified, that is, SMAD4, PTEN, and BCL2L11, converging into the FoxO signaling pathway, known to have a significant role in aging mechanisms. For the first time, this study shows the age‐related increase of plasma miR‐19a/b‐3p in old subjects but a decrease in centenarians. This decrease is more pronounced in healthy centenarians and was confirmed by the modified pattern of isomiRs comparing healthy and unhealthy centenarians. Thus, our study paves the way for functional studies using c‐miRs and isomiRs as additional parameter to track the onset of aging and age‐related diseases using new potential biomarkers. 相似文献
995.
Kurowska M Daszkowska-Golec A Gruszka D Marzec M Szurman M Szarejko I Maluszynski M 《Journal of applied genetics》2011,52(4):371-390
Recent advances in large-scale genome sequencing projects have opened up new possibilities for the application of conventional
mutation techniques in not only forward but also reverse genetics strategies. TILLING (Targeting Induced Local Lesions IN
Genomes) was developed a decade ago as an alternative to insertional mutagenesis. It takes advantage of classical mutagenesis,
sequence availability and high-throughput screening for nucleotide polymorphisms in a targeted sequence. The main advantage
of TILLING as a reverse genetics strategy is that it can be applied to any species, regardless of its genome size and ploidy
level. The TILLING protocol provides a high frequency of point mutations distributed randomly in the genome. The great mutagenic
potential of chemical agents to generate a high rate of nucleotide substitutions has been proven by the high density of mutations
reported for TILLING populations in various plant species. For most of them, the analysis of several genes revealed 1 mutation/200–500 kb
screened and much higher densities were observed for polyploid species, such as wheat. High-throughput TILLING permits the
rapid and low-cost discovery of new alleles that are induced in plants. Several research centres have established a TILLING
public service for various plant species. The recent trends in TILLING procedures rely on the diversification of bioinformatic
tools, new methods of mutation detection, including mismatch-specific and sensitive endonucleases, but also various alternatives
for LI-COR screening and single nucleotide polymorphism (SNP) discovery using next-generation sequencing technologies. The
TILLING strategy has found numerous applications in functional genomics. Additionally, wide applications of this throughput
method in basic and applied research have already been implemented through modifications of the original TILLING strategy,
such as Ecotilling or Deletion TILLING. 相似文献
996.
PEGylated multivalent structures are a new class of platform for biological applications due to their biocompatibility properties. Here, we present the synthesis of a trivalent structure 1 based on poly(ethylene glycol) units (PEG) as potential synthetic multifunctional carrier molecule. To evaluate whether this PEGylated platform could be useful for the conjugation of bioactive compounds, a well-known lipopolysaccharide (LPS) inhibitor 2, developed in our laboratory, was selected to be conjugated to 1. The LPS-neutralizing activity of the resulted conjugates and precursors was established using the chromogenic Limulus amebocyte lysate (LAL) assay. The trivalent structure 1 did not show LPS-binding activity, nonconjugate LPS inhibitor 2 showed high LPS-neutralizing activity, and the trivalent conjugate 4 displayed increased LPS-neutralizing activity and a reduced toxicity profile. These results prove the efficacy of this trivalent platform as a multivalent ligand scaffold for biological applications. 相似文献
997.
José Carlos Franco Elsa Borges da Silva Taiadjana Fortuna Elisabete Cortegano Manuela Branco Pompeo Suma Ivan La Torre Agatino Russo Miriam Elyahu Alex Protasov Anat Levi-Zada Zvi Mendel 《Biological Control》2011,58(3):230-238
The present study was aimed at elucidating the role of lavandulyl senecioate (LS), the sex pheromone of Planococcus ficus, in host selection of the parasitoid Anagyrus sp. near pseudococci. Field trials were carried out in Portugal, Italy and Israel. The effect of LS on the parasitism rate of the wasp was determined by exposing sentinel mealybugs combined with pheromone dispensers impregnated with LS, in comparison with other baits: lavandulyl isovalerate (LI); planococcyl acetate (PAc); and unbaited control traps. In addition, in order to study the host location behavior of A. sp. near pseudococci, pheromone dispensers were placed at three different distances: inside the trap, 30 or 60 cm away from the trap. The number of parasitoid females inside the traps, the number of parasitized mealybugs, and the number of days required for the first parasitoid emergence were recorded. The response of A. sp. near pseudococci females to different doses of LS (25–1350 μg) was also evaluated using sticky plate traps. The rate of mealybug parasitism by A. sp. near pseudococci was significantly increased by LS in the three parasitoid populations. PAc and LI had no significant effect on the wasp parasitism rate in most of the trials. However, the Italian population of the parasitoid responded to PAc, showing apparently a different behavioral pattern. The number of parasitoid females trapped did not significantly differ between tested doses of LS. The use of LS as an arrestant in host location by the A. sp. near pseudococci female is discussed. 相似文献
998.
Kuester M Becker GL Hardes K Lindberg I Steinmetzer T Than ME 《Biological chemistry》2011,392(11):973-981
In eucaryotes, many secreted proteins and peptides are proteolytically excised from larger precursor proteins by a specific class of serine proteases, the proprotein/prohormone convertases (PCs). This cleavage is essential for substrate activation, making the PCs very interesting pharmacological targets in cancer and infectious disease research. Correspondingly, their structure, function and inhibition are intensely studied - studies that require the respective target proteins in large amounts and at high purity. Here we describe the development of a novel purification protocol of furin, the best-studied member of the PC family. We combined the heterologous expression of furin from CHO cells with a novel purification scheme employing an affinity step that efficiently extracts only active furin from the conditioned medium by using furin-specific inhibitor moieties as bait. Several potential affinity tags were synthesized and their binding to furin characterized. The best compound, Biotin-(Adoa)(2)-Arg-Pro-Arg-4-Amba coupled to streptavidin-Sepharose beads, was used in a three-step chromatographic protocol and routinely resulted in a high yield of a homogeneous furin preparation with a specific activity of ~60 units/mg protein. This purification and the general strategy can easily be adapted to the efficient purification of other PC family members. 相似文献
999.
1000.
SUMMARY Modularity of the cranidium of Crassifimbra? metalaspis, a Cambrian ptychoparioid trilobite, is investigated using landmark‐based geometric morphometric methods to gain insight into the integration among morphogenetic processes responsible for shaping the head of an ancient arthropod. Of particular interest is the extent to which the structure of phenotypic integration was governed by direct interactions among developmental pathways, because these interactions may generate long‐term constraints on evolutionary innovation. A modified two‐way ANOVA decomposes cranidial shape variation into components representing symmetric variation among individuals and fluctuating asymmetry (FA). The structure of integration of each of these components is inferred from correlated deviations in shape among nine partitions of the cranidium. Significant correlation among partitions in FA indicates direct interactions among their respective developmental pathways. An a priori hypothesis that modularity was determined by functional association among partitions is not well supported by the among‐partition correlation structure for either component of variation. Instead, exploratory analyses reveal that phenotypic integration was strongly influenced by spatially localized morphogenetic controls. Comparison of the structures of the Individuals and FA components of variation reveals that the two share relatively few commonalities: the structure of phenotypic integration was only weakly influenced by direct interactions. The large contribution of parallel variation to phenotypic integration suggests that modularity was unlikely to have imposed a long‐term constraint on evolutionary innovation in these early trilobites. 相似文献