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991.
Wang Jing Yang Jiebin Han Chunru Cai Liewan Li Xibin Sandra G. F. Bukkens 《植物科学评论》1999,18(3):403-416
Pesticide residues in agricultural produce were examined in two villages of Qianjiang municipality, Hubei province, PR China. Six food groups were sampled from the fields prior to harvesting from the farmers' market and from farmers' homes. Organochlorine residues were detected in almost all examined food groups, with residue levels significantly lower than the national tolerances (MRL). Total BHC residues were on average 31.7?µg/kg and DDT 102.5 (µg/kg. Organophosphorus residues were detected in vegetable samples. Mean residue levels of phoxim and methamidophos in vegetables were 89.9?µg/kg and 36.5?µg/kg, respectively, both exceeding the MRL. Estimated daily intakes (EDIs) of pesticide residues per person, based on the six food groups sampled, were 4.88?mg for total DDT, 2.04 (µg for total BHC, and 19.33 (µg for methamidophos. The overall results show that the increased use and misuse of pesticides for crop protection in Qianjiang municipality, notably in vegetable production, have led to worrisome levels of pesticide contamination of agricultural produce that may carry certain risks for human health. 相似文献
992.
Meyer EH Solheim C Tanz SK Bonnard G Millar AH 《The Journal of biological chemistry》2011,286(29):26081-26092
NADH-ubiquinone oxidoreductase (Complex I, EC 1.6.5.3) is the largest complex of the mitochondrial respiratory chain. In eukaryotes, it is composed of more than 40 subunits that are encoded by both the nuclear and mitochondrial genomes. Plant Complex I differs from the enzyme described in other eukaryotes, most notably due to the large number of plant-specific subunits in the membrane arm of the complex. The elucidation of the assembly pathway of Complex I has been a long-standing research aim in cellular biochemistry. We report the study of Arabidopsis mutants in Complex I subunits using a combination of Blue-Native PAGE and immunodetection to identify stable subcomplexes containing Complex I components, along with mass spectrometry analysis of Complex I components in membrane fractions and two-dimensional diagonal Tricine SDS-PAGE to study the composition of the largest subcomplex. Four subcomplexes of the membrane arm of Complex I with apparent molecular masses of 200, 400, 450, and 650 kDa were observed. We propose a working model for the assembly of the membrane arm of Complex I in plants and assign putative roles during the assembly process for two of the subunits studied. 相似文献
993.
A life cycle assessment has been completed of potential biogas infrastructures on a regional scale. Centralised and distributed infrastructures were considered along with biogas end uses of Combined Heat and Power (CHP) and injection to the gas grid for either transport fuel or domestic heating end uses. Damage orientated (endpoint) life cycle impact assessment method identified that CHP with 80% heat utilisation had the least environmental impact, followed by transport fuel use. Utilisation for domestic heating purposes via the gas grid was found to perform less well. A 32% difference in transportation requirement between the centralised and distributed infrastructures was found to have a relatively small effect on the overall environmental impact. Global warming impacts were significantly affected by changes in methane emissions at upgrading stage, highlighting the importance of minimising operational losses. 相似文献
994.
John Torous Sandra Bucci Imogen H. Bell Lars V. Kessing Maria FaurholtJepsen Pauline Whelan Andre F. Carvalho Matcheri Keshavan Jake Linardon Joseph Firth 《World psychiatry》2021,20(3):318
As the COVID‐19 pandemic has largely increased the utilization of telehealth, mobile mental health technologies – such as smartphone apps, virtual reality, chatbots, and social media – have also gained attention. These digital health technologies offer the potential of accessible and scalable interventions that can augment traditional care. In this paper, we provide a comprehensive update on the overall field of digital psychiatry, covering three areas. First, we outline the relevance of recent technological advances to mental health research and care, by detailing how smartphones, social media, artificial intelligence and virtual reality present new opportunities for “digital phenotyping” and remote intervention. Second, we review the current evidence for the use of these new technological approaches across different mental health contexts, covering their emerging efficacy in self‐management of psychological well‐being and early intervention, along with more nascent research supporting their use in clinical management of long‐term psychiatric conditions – including major depression; anxiety, bipolar and psychotic disorders; and eating and substance use disorders – as well as in child and adolescent mental health care. Third, we discuss the most pressing challenges and opportunities towards real‐world implementation, using the Integrated Promoting Action on Research Implementation in Health Services (i‐PARIHS) framework to explain how the innovations themselves, the recipients of these innovations, and the context surrounding innovations all must be considered to facilitate their adoption and use in mental health care systems. We conclude that the new technological capabilities of smartphones, artificial intelligence, social media and virtual reality are already changing mental health care in unforeseen and exciting ways, each accompanied by an early but promising evidence base. We point out that further efforts towards strengthening implementation are needed, and detail the key issues at the patient, provider and policy levels which must now be addressed for digital health technologies to truly improve mental health research and treatment in the future. 相似文献
995.
Clara E. Cho Diana Sánchez-Hernández Sandra A. Reza-López Pedro S.P. Huot Young-In Kim G. Harvey Anderson 《Epigenetics》2013,8(7):710-719
Our aim was to comprehensively analyze promoter hypermethylation of a panel of novel and known methylation markers for thyroid neoplasms and to establish their relationship with BRAF mutation and clinicopathologic parameters of thyroid cancer. A cohort of thyroid tumors, consisting of 44 cancers and 44 benign thyroid lesions, as well as 15 samples of adjacent normal thyroid tissue, was evaluated for BRAF mutation and promoter hypermethylation. Genes for quantitative methylation specific PCR (QMSP) were selected by a candidate gene approach. Twenty-two genes were tested: TSHR, RASSF1A, RARβ2, DAPK, hMLH1, ATM, S100, p16, CTNNB1, GSTP1, CALCA, TIMP3, TGFßR2, THBS1, MINT1, CTNNB1, MT1G, PAK3, NISCH, DCC, AIM1 and KIF1A. The PCR-based “mutector assay” was used to detect BRAF mutation. All p values reported are two sided. Considerable overlap was seen in the methylation markers among the different tissue groups. Significantly higher methylation frequency and level were observed for KIF1A and RARß2 in cancer samples compared with benign tumors. A negative correlation between BRAF mutation and RASSF1A methylation, and a positive correlation with RARß2 methylation were observed in accordance with previous results. In addition, positive correlation with TIMP3 and a marginal correlation with DCC methylation were observed. The present study constitutes a comprehensive promoter methylation profile of thyroid neoplasia and shows that results must be analyzed in a tissue-specific manner to identify clinically useful methylation markers. Integration of genetic and epigenetic changes in thyroid cancer will help identify relevant biologic pathways that drive its development. 相似文献
996.
Martin Neumann Ebru Coskun Lars Fransecky Liliana H. Mochmann Isabelle Bartram Nasrin Farhadi Sartangi Sandra Heesch Nicola G?kbuget Stefan Schwartz Christian Brandts Cornelia Schlee Rainer Haas Ulrich Dührsen Martin Griesshammer Hartmut D?hner Gerhard Ehninger Thomas Burmeister Olga Blau Eckhard Thiel Dieter Hoelzer Wolf-Karsten Hofmann Claudia D. Baldus 《PloS one》2013,8(1)
Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) has been identified as high-risk subgroup of acute T-lymphoblastic leukemia (T-ALL) with a high rate of FLT3-mutations in adults. To unravel the underlying pathomechanisms and the clinical course we assessed molecular alterations and clinical characteristics in a large cohort of ETP-ALL (n = 68) in comparison to non-ETP T-ALL adult patients. Interestingly, we found a high rate of FLT3-mutations in ETP-ALL samples (n = 24, 35%). Furthermore, FLT3 mutated ETP-ALL was characterized by a specific immunophenotype (CD2+/CD5-/CD13+/CD33-), a distinct gene expression pattern (aberrant expression of IGFBP7, WT1, GATA3) and mutational status (absence of NOTCH1 mutations and a low frequency, 21%, of clonal TCR rearrangements). The observed low GATA3 expression and high WT1 expression in combination with lack of NOTCH1 mutations and a low rate of TCR rearrangements point to a leukemic transformation at the pluripotent prothymocyte stage in FLT3 mutated ETP-ALL. The clinical outcome in ETP-ALL patients was poor, but encouraging in those patients with allogeneic stem cell transplantation (3-year OS: 74%). To further explore the efficacy of targeted therapies, we demonstrate that T-ALL cell lines transfected with FLT3 expression constructs were particularly sensitive to tyrosine kinase inhibitors. In conclusion, FLT3 mutated ETP-ALL defines a molecular distinct stem cell like leukemic subtype. These data warrant clinical studies with the implementation of FLT3 inhibitors in addition to early allogeneic stem cell transplantation for this high risk subgroup. 相似文献
997.
Pauline M. Leite Rodrigo S. Gomes Amanda B. Figueiredo Tiago D. Serafim Wagner L. Tafuri Carolina C. de Souza Sandra A. L. Moura Juliana L. R. Fietto Maria N. Melo Fátima Ribeiro-Dias Milton A. P. Oliveira Ana Rabello Luís C. C. Afonso 《PLoS neglected tropical diseases》2012,6(10)
Background
Leishmania (Viannia) braziliensis has been associated with a broad range of clinical manifestations ranging from a simple cutaneous ulcer to destructive mucosal lesions. Factors leading to this diversity of clinical presentations are not clear, but parasite factors have lately been recognized as important in determining disease progression. Given the fact that the activity of ecto-nucleotidases correlates with parasitism and the development of infection, we evaluated the activity of these enzymes in promastigotes from 23 L. braziliensis isolates as a possible parasite-related factor that could influence the clinical outcome of the disease.Methodology/Principal Findings
Our results show that the isolates differ in their ability to hydrolyze adenine nucleotides. Furthermore, we observed a positive correlation between the time for peak of lesion development in C57BL/6J mice and enzymatic activity and clinical manifestation of the isolate. In addition, we found that L. (V.) braziliensis isolates obtained from mucosal lesions hydrolyze higher amounts of adenine nucleotides than isolates obtained from skin lesions. One isolate with high (PPS6m) and another with low (SSF) ecto-nucleotidase activity were chosen for further studies. Mice inoculated with PPS6m show delayed lesion development and present larger parasite loads than animals inoculated with the SSF isolate. In addition, PPS6m modulates the host immune response by inhibiting dendritic cell activation and NO production by activated J774 macrophages. Finally, we observed that the amastigote forms from PPS6m and SSF isolates present low enzymatic activity that does not interfere with NO production and parasite survival in macrophages.Conclusions/Significance
Our data suggest that ecto-nucleotidases present on the promastigote forms of the parasite may interfere with the establishment of the immune response with consequent impaired ability to control parasite dissemination and this may be an important factor in determining the clinical outcome of leishmaniasis. 相似文献998.
999.
da Silva Filho AA de Sousa JP Soares S Furtado NA Andrade e Silva ML Cunha WR Gregório LE Nanayakkara NP Bastos JK 《Zeitschrift für Naturforschung. C, Journal of biosciences》2008,63(1-2):40-46
Baccharis dracunculifolia D.C. (Asteraceae) is the most important plant source of the Brazilian green propolis. Since propolis is known for its antimicrobial activity, the aim of this work was to evaluate the antimicrobial activities of B. dracunculifolia and some of its isolated compounds. The results showed that the leaves extract of B. dracunculifolia (BdE) presents antifungal and antibacterial activities, especially against Candida krusei and Cryptococcus neoformans, for which the BdE showed IC50 values of 65 microg mL(-1) and 40 microg mL(-1), respectively. In comparison to the BdE, it was observed that the green propolis extract (GPE) showed better antimicrobial activity, displaying an IC50 value of 9 microg mL(-1) against C. krusei. Also, a phytochemical study of the BdE was carried out, affording the isolation of ursolic acid (1), 2a-hydroxy-ursolic acid (2), isosakuranetin (3), aromadendrin-4'-methylether (4), baccharin (5), viscidone (6), hautriwaic acid lactone (7), and the clerodane diterpene 8. This is the first time that the presence of compounds 1, 2, and 8 in B. dracunculifolia has been reported. Among the isolated compounds, 1 and 2 showed antibacterial activity against methicillin-resistant Staphylococcus aureus, displaying IC50 values of 5 microg mL(-1) and 3 microg mL(-1), respectively. 3 was active against C. neoformans, showing an IC50 value of 15 microg mL(-1) and a MIC value of 40 microg mL(-1), while compounds 4-8 were inactive against all tested microorganisms. The results showed that the BdE, similar to the GPE, displays antimicrobial activity, which may be related to the effect of several compounds present in the crude extract. 相似文献
1000.
High throughput gene expression measurement with real time PCR in a microfluidic dynamic array 总被引:1,自引:0,他引:1
We describe a high throughput gene expression platform based on microfluidic dynamic arrays. This system allows 2,304 simultaneous real time PCR gene expression measurements in a single chip, while requiring less pipetting than is required to set up a 96 well plate. We show that one can measure the expression of 45 different genes in 18 tissues with replicates in a single chip. The data have excellent concordance with conventional real time PCR and the microfluidic dynamic arrays show better reproducibility than commercial DNA microarrays. 相似文献