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61.
62.
Sanjeev Shukla Haripaul Sharma Ata Abbas Gregory T. MacLennan Pingfu Fu David Danielpour Sanjay Gupta 《PloS one》2013,8(1)
Disease aggressiveness remains a critical factor to the progression of prostate cancer. Transformation of epithelial cells to mesenchymal lineage, associated with the loss of E-cadherin, offers significant invasive potential and migration capability. Recently, Special AT-rich binding protein (SATB1) has been linked to tumor progression. SATB1 is a cell-type restricted nuclear protein, which functions as a tissue-specific organizer of DNA sequences during cellular differentiation. Our results demonstrate that SATB1 plays significant role in prostate tumor invasion and migration and its nuclear localization correlates with disease aggressiveness. Clinical specimen analysis showed that SATB1 was predominantly expressed in the nucleus of high-grade tumors compared to low-grade tumor and benign tissue. A progressive increase in the nuclear levels of SATB1 was observed in cancer tissues compared to benign specimens. Similarly, SATB1 protein levels were higher in a number of prostate cancer cells viz. HPV-CA-10, DU145, DUPro, PC-3, PC-3M, LNCaP and C4-2B, compared to non-tumorigenic PZ-HPV-7 cells. Nuclear expression of SATB1 was higher in biologically aggressive subclones of prostate cancer cells with their respective parental cell lines. Furthermore, ectopic SATB1 transfection conferred increased cell motility and invasiveness in immortalized human prostate epithelial PZ-HPV-7 cells which correlated with the loss of E-cadherin expression. Consequently, knockdown of SATB1 in highly aggressive human prostate cancer PC-3M cells inhibited invasiveness and tumor growth in vivo along with increase in E-cadherin protein expression. Our findings demonstrate that SATB1 has ability to promote prostate cancer aggressiveness through epithelial-mesenchymal transition. 相似文献
63.
Increasing salinity induced a marked reduction in the plant growth, thoughPhaseolus seedlings tolerated salinity up to 120 mM NaCI. A great reduction in sugar and protein contents occurred with increasing salinity, whereas soluble nitrogen compounds and the relative contents of the photosynthetic pigments were increased in the treated plants. Increasing Ca concentration in the salinized medium appeared to improve the plant growth and to increase the contents of saccharides and proteins in the NaCl-treated plants. This suggests that Ca could be added to salinized media to overcome the deleterious effects of salinity on the growth and productivity of leguminous crop plants. 相似文献
64.
Shi J Zhang T Zhou C Chohan MO Gu X Wegiel J Zhou J Hwang YW Iqbal K Grundke-Iqbal I Gong CX Liu F 《The Journal of biological chemistry》2008,283(42):28660-28669
Two groups of tau, 3R- and 4R-tau, are generated by alternative splicing of tau exon 10. Normal adult human brain expresses equal levels of them. Disruption of the physiological balance is a common feature of several tauopathies. Very early in their life, individuals with Down syndrome (DS) develop Alzheimer-type tau pathology, the molecular basis for which is not fully understood. Here, we demonstrate that Dyrk1A, a kinase encoded by a gene in the DS critical region, phosphorylates alternative splicing factor (ASF) at Ser-227, Ser-234, and Ser-238, driving it into nuclear speckles and preventing it from facilitating tau exon 10 inclusion. The increased dosage of Dyrk1A in DS brain due to trisomy of chromosome 21 correlates to an increase in 3R-tau level, which on abnormal hyperphosphorylation and aggregation of tau results in neurofibrillary degeneration. Imbalance of 3R- and 4R-tau in DS brain by Dyrk1A-induced dysregulation of alternative splicing factor-mediated alternative splicing of tau exon 10 represents a novel mechanism of neurofibrillary degeneration and may help explain early onset tauopathy in individuals with DS. 相似文献
65.
The association of the placental MTHFR 3′‐UTR polymorphisms,promoter methylation,and MTHFR expression with preeclampsia 下载免费PDF全文
66.
Over the second half of the past century, the Zloul Valley has undergone rapid and intense changes, such as deforestation and massive clearing as well as a grazing ban in olive plots since the introduction of olive cultivation approximately 30 years ago. The aim of this study was to explore these rapidly changing ecosystems. The floristic analysis revealed a more pronounced anthropozoic impact on the Chamaerops humilis and Ampelodesmos mauritanicus steppe group, which displayed the lowest floristic diversity, with a Shannon–Weaver index of 3.72, and a very high disturbance, of 68.85%. The grazing ban in olive plots had a positive effect on floristic richness and diversity, with the Shannon–Weaver index reaching a maximum value of 4.67. However, the floristic composition remained unbalanced, with an equitability index of 0.61 and a perturbation index of 70.8%. Therefore, these ecosystems have not been able to recover their initial equilibrium despite being under protection for long. The ecosystems of the Zloul Valley demonstrated alarming levels of degradation, especially on the southern slopes of Jbel Ikraa and Jnab Diss. Urgent measures must be taken to mitigate biodiversity loss and soil erosion as a matter of priority. 相似文献
67.
R N Mitchell A C Shaw Y K Weaver P Leder A K Abbas 《The Journal of biological chemistry》1991,266(14):8856-8860
Membrane-bound immunoglobulin (mIg) is the antigen receptor on B lymphocytes mediating early events in antigen presentation and signal transduction. Wild-type human mIgM constructs transfected into the murine B-cell lymphoma A20 are expressed as transmembrane proteins with antigen presentation and signaling functions comparable to the endogenous mIgG2A; the transfected wild-type mIgM is internalized rapidly after anti-Ig cross-linking. Transfected constructs lacking the normal three-amino acid cytoplasmic tail are expressed exclusively as phosphatidylinositol-linked proteins, lack both antigen presentation and signal transduction functions, and are internalized slowly following anti-Ig binding. The molecular mass of the cytoplasmic tail-deleted phosphatidylinositol-linked Ig molecule is consistent with cleavage of the transmembrane residues during processing. Cytoplasmic domains may therefore regulate the mode of expression of membrane proteins and thereby influence their functional capabilities. 相似文献
68.
Yasir Iftikhar Mazhar Abbas Mustansar Mubeen Muhammad Zafar-ul-Hye Faheema Bakhtawar Sonum Bashir Ashara Sajid Muhammad Asif Shabbir 《Phyton》2021,90(4):1063-1074
Tristeza is a devastating viral disease in all the citrus growing countries throughout the world and has killed millions of citrus trees in severely affected orchards. The citrus species grafted on sour orange rootstock are affected
by this disease. Predominantly, the sweet orange, grapefruit and lime trees grafted on sour orange exhibit severe
symptoms like quick decline, vein clearing, pin holing, bark scaling and degeneration leading to variable symptoms. Symptomatic expression of Citrus tristeza virus (CTV) in different hosts has been attributed to virus isolates
which are from severe to mild. Different serological and molecular assays have been deployed to differentiate the
strains of CTV. Citrus tristeza virus is diversified towards its strains on the basis of biological, serological and
molecular characterization. Phenotypic expression is due to genetic alteration and different molecular basis have
now been adopted for strain differentiation. This review will give a brief idea about the different CTV isolates,
their characterization based on nucleic acid and serological assays. Different methods along with salient features
for strain characterization has also been reviewed. This review will also open the new aspects towards formulation
of management strategies through different detection techniques. 相似文献
69.
Journal of Ichthyology - The Suez Gulf is one of the most important water bodies north of the Red Sea that contribute significantly in fish production in Egypt. The current study represents the... 相似文献
70.
Saghir Abbas Muhammad Tariq Javed Qasim Ali Muhammad Sohail Akram Kashif Tanwir Shafaqat Ali Hassan Javed Chaudhary Naeem Iqbal 《Physiology and Molecular Biology of Plants》2021,27(2):297
Cadmium (Cd) in soil–plant system can abridge plant growth by initiating alterations in root zones. Hydroponics and rhizoboxes are useful techniques to monitor plant responses against various natural and/or induced metal stresses. However, soil based studies are considered more appropriate in order to devise efficient food safety and remediation strategies. The present research evaluated the Cd-mediated variations in elemental dynamics of rhizospheric soil together with in planta ionomics and morpho-physio-biochemical traits of two differentially Cd responsive maize cultivars. Cd-sensitive (31P41) and Cd-tolerant (3062) cultivars were grown in pots filled with 0, 20, 40, 60 and 80 µg/kg CdCl2 supplemented soil. The results depicted that the maize cultivars significantly influenced the elemental dynamics of rhizosphere as well as in planta mineral accumulation under applied Cd stress. The uptake and translocation of N, P, K, Ca, Mg, Zn and Fe from rhizosphere and root cell sap was significantly higher in Cd stressed cv. 3062 as compared to cv. 31P41. In sensitive cultivar (31P41), Cd toxicity resulted in significantly prominent reduction of biomass, leaf area, chlorophyll, carotenoids, protein contents as well as catalase activity in comparison to tolerant one (3062). Analysis of tolerance indexes (TIs) validated that cv. 3062 exhibited advantageous growth and efficient Cd tolerance due to elevated proline, phenolics and activity of antioxidative machinery as compared to cv. 31P41. The cv. 3062 exhibited 54% and 37% less Cd bio-concentration (BCF) and translocation factors (TF), respectively in comparison to cv. 31P41 under highest Cd stress regime. Lower BCF and TF designated a higher Cd stabilization by tolerant cultivar (3062) in rhizospheric zone and its potential use in future remediation plans. 相似文献