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991.
Eighty-seven species belonging to 59 genera and 33 plant families identified in the study area are presented. The three families with the most species represented were Labiatae (nine aquatic species), Compositae (seven species), and Salicaceae (seven species). The genera most represented wereMentha (six species),Polygonum (five species), andSalix (five species). Sixty-three folk-medicinal aquatic species (73.3%) had similar therapeutic uses in neighboring countries, while the 24 remaining species (26.7%) did not show therapeutic similarity with their use in other countries. Emerged species (plants rooted in soil under water but which emerge partially above the water’s surface) were the most recorded, while amphibious, submerged, and floating species were the least recorded. The folk-medicinal importance of the recorded aquatic species were classified by rank-order priority (ROP). Twenty-one species (24%) had ROP values higher than 50, indicating the highest popularity level in folk-medicinal potentiality; 26 species (29.9%) had therapeutic effects informed by fewer than three informants and were therefore excluded from further consideration; 40 species (46.1%) had ROP values of less than 50, and were thus classified as nonpopular medicinal plants.  相似文献   
992.
Summary In the wood destroying basidiomycete Schizophyllum commune a method is described to recognize the onset of dikaryosis rapidly in using recessive genetic markers. The gene ai +/ai causes in its mutant recessive allele (ai) the production of dark coloured fruit bodies. This can be made use of to evaluate macroscopically the formation of a dikaryon. Another useful marker is the gene rd +/rd. The recessive allele (rd) causes phenotypically the formation of a round looking mycelium instead of the fringed looking mycelium, the wild type. This genetic marker which is closely linked to the A-incompatibility factor is therefore also qualified to detect the onset of dikaryosis without much effort.  相似文献   
993.
Process water and effluents from mining operations treating sulfide rich ores often contain considerable concentrations of metastable inorganic sulfur compounds such as thiosulfate and tetrathionate. These species may cause environmental problems if released to downstream recipients due to oxidation to sulfuric acid catalyzed by acidophilic microorganisms. Molecular phylogenic analysis of the tailings pond and recipient streams identified psychrotolerant and mesophilic inorganic sulfur compound oxidizing microorganisms. This suggested year round thiosalt oxidation occurs. Mining process waters may also contain inhibiting substances such as thiocyanate from cyanidation plants. However, toxicity experiments suggested their expected concentrations would not inhibit thiosalt oxidation by Acidithiobacillus ferrivorans SS3. A mixed culture from a permanently cold (4-6 °C) low pH environment was tested for thiosalt removal in a reactor design including a biogenerator and a main reactor containing a biofilm carrier. The biogenerator and main reactors were successively reduced in temperature to 5-6 °C when 43.8% of the chemical oxidation demand was removed. However, it was found that the oxidation of thiosulfate was not fully completed to sulfate since low residual concentrations of tetrathionate and trithionate were found in the discharge. This study has demonstrated the potential of using biotechnological solutions to remove inorganic sulfur compounds at 6°C and thus, reduce the impact of mining on the environment.  相似文献   
994.
The angiotensin II peptide analog [Sar(1),Ile(4),Ile(8)]AngII (SII) is a biased AT(1A) receptor agonist that stimulates receptor phosphorylation, β-arrestin recruitment, receptor internalization, and β-arrestin-dependent ERK1/2 activation without activating heterotrimeric G-proteins. To determine the scope of G-protein-independent AT(1A) receptor signaling, we performed a gel-based phosphoproteomic analysis of AngII and SII-induced signaling in HEK cells stably expressing AT(1A) receptors. A total of 34 differentially phosphorylated proteins were detected, of which 16 were unique to SII and eight to AngII stimulation. MALDI-TOF/TOF mass fingerprinting was employed to identify 24 SII-sensitive phosphoprotein spots, of which three (two peptide inhibitors of protein phosphatase 2A (I1PP2A and I2PP2A) and prostaglandin E synthase 3 (PGES3)) were selected for validation and further study. We found that phosphorylation of I2PP2A was associated with rapid and transient inhibition of a β-arrestin 2-associated pool of protein phosphatase 2A, leading to activation of Akt and increased phosphorylation of glycogen synthase kinase 3β in an arrestin signalsome complex. SII-stimulated PGES3 phosphorylation coincided with an increase in β-arrestin 1-associated PGES3 and an arrestin-dependent increase in cyclooxygenase 1-dependent prostaglandin E(2) synthesis. These findings suggest that AT(1A) receptors regulate a robust G protein-independent signaling network that affects protein phosphorylation and autocrine/paracrine prostaglandin production and that these pathways can be selectively modulated by biased ligands that antagonize G protein activation.  相似文献   
995.
The environment encountered in secondary lymphoid organs (e.g., lymph nodes) influences the outcome of immune responses. Immunization of mice with type VII collagen, an adhesion protein expressed at the cutaneous basement membrane, induces experimental epidermolysis bullosa acquisita (EBA). In this model, clinical disease is associated with the H2s haplotype of the MHC found in SJL/J mice. Most other strains (e.g., BALB/c, C57BL/6, NZM2410/J) are resistant to clinical disease, despite autoantibody production. Comparison of autoantibody response in EBA-resistant and -susceptible mice showed an IgG2-dominated response in the latter. We hypothesized that EBA susceptibility is due to specific cytokine gene expression in draining lymph nodes (dLN). To challenge this hypothesis, EBA-susceptible (SJL/J) and -resistant (BALB/c, C57BL/6) mice were immunized with type VII collagen, followed by analysis of clinical phenotype, subclasses of circulating and tissue-bound autoantibodies, complement activation, and cytokine gene expression in dLN. Disease manifestation was associated with induction of complement-fixing autoantibodies, confirming previous observations. Furthermore, however, IFN-γ/IL-4 ratio in dLN of EBA-susceptible mice was significantly increased compared with EBA-resistant strains, suggesting a Th1 polarization. Immunization of H2s-congenic C57BL/6 mice (B6.SJL-H2s) led to Th1 polarization in dLN and clinical disease. In addition to their cytokine milieu, EBA-susceptible and -resistant mice also differed regarding the expression of FcγR on peripheral leukocytes, in which a higher FcγRIV expression in SJL/J and B6.SJL-H2s mice, compared with C57BL/6, was associated with skin lesions. In summary, blistering in experimental EBA is regulated by both adaptive (divergent class switch recombination due to polarized cytokine expression) and innate (FcγR expression) immune mechanisms.  相似文献   
996.
The discovery in 1998 that triclosan has a site-specific action in the bacterial cell as an inhibitor of NADH- or NADPH-dependent enoyl-acyl carrier protein reductase led to a lively debate in the scientific press. The thesis of this debate was that such a mode of action may allow triclosan to induce resistance and cross-resistance in bacterial cells. The debate last saw review in 2004, and this paper aims at updating our knowledge in this area, given recent research on the topic.  相似文献   
997.
Cancer cervix is one of the leading causes of cancer-related mortality among women worldwide. It is believed that the host genetic factors such as inflammation-induced cytokines may play a role in cervical carcinogenesis. The interleukin-1β (IL-1β) gene contains several single nucleotide polymorphisms. One of them, C-511T, which in the promoter region has been associated with increased IL-1β production and with increased risk of developing cancers. We assessed the association between the IL-1β C-511T polymorphism and cervical cancer risk in a case-control study among 100 histopathologically confirmed Egyptian women with cervical cancer and 50 age-matched, cervical cytology negative, healthy controls by polymerase chain reaction-restriction fragment length polymorphism. Plasma levels of IL-1β were assayed by enzyme-linked immunosorbent assay. There was significant increase in the mean plasma IL-1β level in cervical cancer cases (43.40 ± 25.95 pg/ml) when compared with controls (30.51 ± 18.28 pg/ml, P = 0.002). The plasma levels above the 75th percentile of controls (IL-1β ≥ 45.74 pg/ml) were significantly associated with a 2.49-fold increased risk of cervical cancer. The significant increase in IL-1β concentration in cervical cancer cases was observed only among cervical cancer cases carrying C-511T variant genotypes. T/T genotype of IL-1β polymorphism was significantly higher in cervical cancer cases compared with controls (57 vs. 38%; OR = 2.16; P = 0.028) and the T allele carriage was significantly associated with cervical cancer risk (OR = 2.00, 95% CI = 1.19-3.38, and P = 0.008). In conclusion, plasma IL-1β level and IL-1β C-511T polymorphism may be considered as candidate biomarkers for cervical cancer in Egyptian women.  相似文献   
998.
Amylases take part with vital role in industries such as food, fermentation; starch processing, textile and paper etc. Increasing amylases demand, high nutrient expenditure and environmental pollution have forced to utilize agro-industrial residues as a low-cost feedstock for enzyme production. In present study, three soil samples were collected from agro-industrial waste dumping areas in District Faisalabad. Ten thermophilic bacterial isolates were separated at 55 °C on the basis of colonial morphology, three isolates (F6, F11, F17) showed prominent zone of clearance applying iodine test on starch agar plates. Bacterial isolate F-11 showed highest amylase activity with DNS method and molecularly identified through 16S RNA sequencing as Bacillus sp. with Accession number MH917294. Four unconventional food wastes (banana, lemon, mango and potato) pretreated with 0.8% sulphuric acid concentrations taking 1000 g/L weight released the highest sugars contents and phenolic components. Maximum amylase activity i.e. 29.23 mg/ml was achieved in mango waste at, 40 °C, with pH 6.0 and 0.17% nitrogenous source adding 8% inoculum size (2 days old) using Response Surface Methodology (RSM) for optimization. Crude amylase confirmed its efficiency in starch hydrolysis that suggested it as potential candidate for application in starch industries.  相似文献   
999.
1000.
Among 50 strains of Pseudomonas aeruginosa tested for the resistance to antibiotics, strain ryn32 was selected for this study based on its resistance level. It showed complete resistance toward aztreonam and almost complete resistance (96%) against kanamycin. Iron nanoparticles (FeNPs) were then prepared and found with diameters 30–50 nm. The threshold level of FeNPs for pyoverdines (PVDs) production by P. aeruginosa ryn32 was found at 25 μM concentration. PVDs production was optimal with pH 7.5, 35°C, succinate as carbon source, ammonium sulfate as nitrogen source at 60 hr fermentation time. Interestingly, when used the PVDs as conjugates with FeNPs they showed antibacterial action against the producing strain and some other gram-negative bacteria. This suggests that the conjugates enter the bacterial cell via the ferriPVDs uptake pathway, which triggers the accumulation of FeNPs inside the cell, which is crucial on bacterial viability. Growth stimulation with the same concentrations of FeNPs and PVDs in separate treatments supported this view.  相似文献   
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