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991.
992.
Selective logging with natural regeneration is advocated as a near‐to‐nature strategy and has been implemented in many forested systems during the last decades. However, the efficiency of such practices for the maintenance of forest species are poorly understood. We compared the species richness, abundance and composition of ground‐dwelling beetles between selectively logged and unlogged forests to evaluate the possible effects of selective logging in a subtropical broad‐leafed forest in southeastern China. Using pitfall traps, beetles were sampled in two naturally regenerating stands after clearcuts (ca. 50 years old, stem‐exclusion stage: selectively logged 20 years ago) and two mature stands (> 80 years old, understory re‐initiation stage: selectively logged 50 years ago) during 2009 and 2010. Overall, selective logging had no significant effects on total beetle richness and abundance, but saproxylic species group and some abundant forest species significantly decreased in abundance in selectively logged plots compared with unlogged plots in mature stands. Beetle assemblages showed significant differences between selectively logged and unlogged plots in mature stands. Some environmental characteristics associated with selective logging (e.g., logging strategy, stand age, and cover of shrub and moss layers) were the most important variables explaining beetle assemblage structure. Our results conclude that selective logging has no significant impacts on overall richness and abundance of ground‐dwelling beetles. However, the negative effects of selective logging on saproxylic species group and some unlogged forest specialists highlight the need for large intact forested areas for sustaining the existence of forest specialist beetles.  相似文献   
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A novel potassium-based dry sorbent (KZrI) was developed for CO2 capture at a low temperature range between 50 °C and 200 °C. The CO2 absorption and regeneration properties of this novel regenerable potassium-based dry sorbent were measured in a fixed-bed reactor during multiple absorption/regeneration cycles at low temperature conditions (CO2 absorption at 50–100 °C and regeneration at 130–200 °C). The total CO2 capture capacity of the KZrI sorbent was maintained during the multiple CO2 absorption/regeneration cycles. The XRD patterns and FTIR analyses of the sorbents after CO2 absorption showed the KHCO3 phase only except for the ZrO2 phase used as support. Even after 10 cycles, any other new structures resulting from the by-product during CO2 absorption were not observed. This phase could be easily converted into the original phase during regeneration, even at a low temperature (130 °C). The KZrI sorbent developed in this study showed excellent characteristics in CO2 absorption and regeneration in that it satisfies the requirements of a large amount of CO2 absorption (91.6 mg CO2/g sorbent) and the complete regeneration at a low temperature condition (1 atm, 150 °C) without deactivation.  相似文献   
996.
Single-chain repressor RRTRES is a derivative of bacteriophage 434 repressor, which contains covalently dimerized DNA-binding domains (amino acids 1-69) of the phage 434 repressor. In this single-chain molecule, the wild type domain R is connected to the mutant domain RTRES by a recombinant linker in a head-to-tail arrangement. The DNA-contacting amino acids of RTRES at the -1, 1,2, and 5 positions of the α3 helix are T, R, E, S respectively. By using a randomized DNA pool containing the central sequence -CATACAAGAAAGNNNNNTTT-. a cyclic, in vitro DNA-binding site selection was performed. The selected population was cloned and the individual members were characterized by determining their binding affinities to RRTRES. The results showed that the optimal operators contained the TTAC or TTCC sequences in the underlined positions as above, and that the Kd values were in the 1×10-12mol/L1×10-11mol/L concentration range. Since the affinity of the natural 434 repressor to its natural operator sites is in the  相似文献   
997.
Saikosaponin productivity was examined in aBupleurum falcatum L. BFHR2 hairy root culture in response to changes in the sucrose content (2≈8%), nitrogen content (0≈250 mM NH4NO3), phosphate content (0≈12 mM NaH2PO4), and the potassium content (0≈87.2 mM KCl) of the culture media. We found that the conditions for maximal saikosaponin production differed from those for optimal root growth. Highest saikosaponin yield was achieved for 8% sucrose, 62 mM NH4NO3, 1.2 mM NaH2PO4, and 0.5 mM KCl.  相似文献   
998.
Effects of spinosad, spinosad bait, and the chloronicotinyl insecticides imidacloprid and thiacloprid on mortality of the adults and larvae of western cherry fruit fly, Rhagoletis indifferens Curran (Diptera: Tephritidae), were determined in the laboratory and the field. Spinosad and spinosad bait caused higher adult mortality than imidacloprid, which caused higher mortality than thiacloprid. Only spinosad bait prevented oviposition. All materials were more toxic to adults when ingested than when topically applied. Spinosad bait had the greatest residual toxicity on leaves, killing 100% of adults when aged for 14 d in the field. When materials were sprayed on infested cherries, numbers of live larvae in fruit after 8 d were lower in imidacloprid and thiacloprid than in spinosad and spinosad bait treatments, which did not differ from the control, but all materials reduced larval emergence over 30 d. In the field, spinosad and spinosad bait were as effective in suppressing larval infestations as azinphos-methyl and carbaryl, whereas imidacloprid was effective in most cases and thiacloprid was generally less effective than azinphos-methyl and carbaryl. Overall, results in the laboratory and field show that spinosad and chloronicotinyl insecticides differed significantly in their effectiveness against adults and larvae of R. indifferens but that spinosad, spinosad bait, and imidacloprid seem to be acceptable substitutes for organophosphate and carbamate insecticides for controlling this fruit fly.  相似文献   
999.

Background

Poor central nervous system penetration of cytotoxic drugs due to the blood brain barrier (BBB) is a major limiting factor in the treatment of brain tumors. Most recurrent glioblastomas (GBM) occur within the peritumoral region. In this study, we describe a hyperthemic method to induce temporary disruption of the peritumoral BBB that can potentially be used to enhance drug delivery.

Methods

Twenty patients with probable recurrent GBM were enrolled in this study. Fourteen patients were evaluable. MRI-guided laser interstitial thermal therapy was applied to achieve both tumor cytoreduction and disruption of the peritumoral BBB. To determine the degree and timing of peritumoral BBB disruption, dynamic contrast-enhancement brain MRI was used to calculate the vascular transfer constant (Ktrans) in the peritumoral region as direct measures of BBB permeability before and after laser ablation. Serum levels of brain-specific enolase, also known as neuron-specific enolase, were also measured and used as an independent quantification of BBB disruption.

Results

In all 14 evaluable patients, Ktrans levels peaked immediately post laser ablation, followed by a gradual decline over the following 4 weeks. Serum BSE concentrations increased shortly after laser ablation and peaked in 1–3 weeks before decreasing to baseline by 6 weeks.

Conclusions

The data from our pilot research support that disruption of the peritumoral BBB was induced by hyperthemia with the peak of high permeability occurring within 1–2 weeks after laser ablation and resolving by 4–6 weeks. This provides a therapeutic window of opportunity during which delivery of BBB-impermeant therapeutic agents may be enhanced.

Trial Registration

ClinicalTrials.gov NCT01851733  相似文献   
1000.
Viral safety is a prerequisite for manufacturing clinical albumin and immunoglobulins from human plasma pools. This study was designed to evaluate the efficacy of cold ethanol fractionation and pasteurization (60°C heat treatment for 10 h) for the removal inactivation of human immunodeficiency virus type 1 (HIV-1) during the manufacturing of albumin and immunoglobulins. Samples from the relevant stages of the production process were spiked with HIV-1, and the amount of virus in each fraction was quantified by the 50% tissue culture infectious dose (TCID50). Both fraction IV fractionation and pasteurization steps during albumin processing were robust and effective in inactivating HIV-1, titers of which were reduced from an initial 8.5 log10 TCID50 to undetectable levels. The log reduction factors achieved were ≥4.5 and ≥6.5, respectively. In addition, fraction III fractionation and pasteurization during immunoglobulins processing were robust and effective in eliminating HIV-1. HIV-1 titers were reduced from an initial 7.3 log10 TCID50 to undetectable levels. The log reduction factors achieved in this case were ≥4.9 and ≥5.3, respectively. These results indicate that the process investigated for the production of albumin and immunoglobulins have sufficient HIV-1 reducing capacity to achieve a high margin of safety.  相似文献   
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