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51.
The 23rd Annual Antibody Engineering, 10th Annual Antibody Therapeutics international conferences, and the 2012 Annual Meeting of The Antibody Society, organized by IBC Life Sciences with contributions from The Antibody Society and two Scientific Advisory Boards, were held December 3–6, 2012 in San Diego, CA. The meeting drew over 800 participants who attended sessions on a wide variety of topics relevant to antibody research and development. As a prelude to the main events, a pre-conference workshop held on December 2, 2012 focused on intellectual property issues that impact antibody engineering. The Antibody Engineering Conference was composed of six sessions held December 3–5, 2012: (1) From Receptor Biology to Therapy; (2) Antibodies in a Complex Environment; (3) Antibody Targeted CNS Therapy: Beyond the Blood Brain Barrier; (4) Deep Sequencing in B Cell Biology and Antibody Libraries; (5) Systems Medicine in the Development of Antibody Therapies/Systematic Validation of Novel Antibody Targets; and (6) Antibody Activity and Animal Models. The Antibody Therapeutics conference comprised four sessions held December 4–5, 2012: (1) Clinical and Preclinical Updates of Antibody-Drug Conjugates; (2) Multifunctional Antibodies and Antibody Combinations: Clinical Focus; (3) Development Status of Immunomodulatory Therapeutic Antibodies; and (4) Modulating the Half-Life of Antibody Therapeutics. The Antibody Society’s special session on applications for recording and sharing data based on GIATE was held on December 5, 2012, and the conferences concluded with two combined sessions on December 5–6, 2012: (1) Development Status of Early Stage Therapeutic Antibodies; and (2) Immunomodulatory Antibodies for Cancer Therapy.  相似文献   
52.
Mechanochemical synthesis of Cu3P in the presence of n‐dodecane results in a material with a secondary particle size distribution of 10 μm, secondary particles which consist of homogeneously agglomerated 20 nm primary particles. The electrochemical performance of Cu3P with lithium is influenced by the reaction depth, in other words by the lower potential cut‐off. During the electrochemical reaction, the displacement of copper by lithium from the Cu3P structure until the formation of Li3P and Cu deteriorates the capacity retention. Improved performance was obtained when the charge potential was limited to 0.50 V (vs. Li/Li+) and the formation of the LixCu3‐xP phase (0 ≤ × ≤ 2). In this case, when the potential is limited to 0.5 V, the capacity is stable for more than 50 cycles. Acceptable electrochemical performances in Li‐ion cells within the voltage range 0.50–2.0 V (vs. Li/Li+) were shown when Cu3P was used as an anode and Li1.2(Ni0.13Mn0.54Co0.13)O2 and LiNi0.5Mn1.5O4 as positive electrode materials.  相似文献   
53.
CD40L has a well-established role in enhancing the immunostimulatory capacity of normal and malignant B cells, but a formulation suitable for clinical use has not been widely available. Like other TNF family members, in vivo and in vitro activity of CD40L requires a homotrimeric configuration, and growing evidence suggests that bioactivity depends on higher-order clustering of CD40. We generated a novel formulation of human recombinant CD40L (CD40L-Tri) in which the CD40L extracellular domain and a trimerization motif are connected by a long flexible peptide linker. We demonstrate that CD40L-Tri significantly expands normal CD19+ B cells by over 20- to 30-fold over 14 days and induces B cells to become highly immunostimulatory antigen-presenting cells (APCs). Consistent with these results, CD40L-Tri-activated B cells could effectively stimulate antigen-specific T responses (against the influenza M1 peptide) from normal volunteers. In addition, CD40L-Tri could induce malignant B cells to become effective APCs, such that tumor-directed immune responses could be probed. Together, our studies demonstrate the potent immune-stimulatory effects of CD40L-Tri on B cells that enable their expansion of antigen-specific human T cells. The potent bioactivity of CD40L-Tri is related to its ability to self-multimerize, which may be facilitated by its long peptide linker.  相似文献   
54.
Two grasshopper species, Stenobothrus rubicundus and Stenobothrus clavatus, were previously shown to hybridize in a narrow contact zone on Mount Tomaros in northern Greece. The species are characterized by complex and completely different courtship songs. In the present study, we investigated female preferences for the courtship songs of S. rubicundus, S. clavatus and hybrids in playback experiments. Playback of the courtship songs revealed assortative preferences in females of the parental species: they significantly more often preferred the songs of conspecific males. Hybrid females showed a lower selectivity than parental females, responding somewhat equally eager to playback of the songs of S. clavatus, S. rubicundus, and natural hybrid song, although less actively to the F1 hybrid song. The results suggest that hybrid males may lose to males of parental species, whereas hybrid females would even have an advantage over parental females. Comparison of responses of females from allopatric populations and Mount Tomaros to different song types shows no evidence for reinforcement. Asymmetry found in female preferences may have implications for the structure of the hybrid zone. © 2013 The Linnean Society of London  相似文献   
55.
Recent research demonstrated that exposure of mice to both inhomogeneous (3–477 mT) and homogeneous (145 mT) static magnetic fields (SMF) generated an analgesic effect toward visceral pain elicited by the intraperitoneal injection of 0.6% acetic acid. In the present work, we investigated behavioral responses such as writhing, entry avoidance, and site preference with the help of a specially designed cage that partially protruded into either the homogeneous (ho) or inhomogeneous (inh) SMF. Aversive effects, cognitive recognition of analgesia, and social behavior governed mice in their free locomotion between SMF and sham sides. The inhibition of pain response (I) for the 0–5, 6–20, and 21–30 min periods following the challenge was calculated by the formula I = 100 (1 ? x/y) in %, where x and y represent the number of writhings in the SMF and sham sides, respectively. In accordance with previous measurements, an analgesic effect was induced in exposed mice (Iho = 64%, P < 0.0002 and Iinh = 62%, P < 0.002). No significant difference was found in the site preference (SMFho, inh vs. sham) indicating that SMF is neither aversive nor favorable. Comparison of writhings observed in the sham versus SMF side of the cage revealed that SMF exposure resulted in significantly fewer writhings than sham (Iho = 64%, P < 0.004 and Iinh = 81%, P < 0.03). Deeper statistical analysis clarified that the lateral SMF gradient between SMF and sham sides could be responsible for most of the analgesic effect (Iho = 91%, P < 0.02 and Iinh = 54%, P < 0.02). Bioelectromagnetics 34:385–396, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
56.

Purpose

Current estimations of the climate impact from indirect land use change (ILUC) caused by biofuels are heavily influenced by assumptions regarding the biofuel production period. The purpose of this paper is to propose a new method (baseline time accounting) that takes global land use dynamics into account that is consistent with the global warming potential, that is applicable to any phenomenon causing land use change, and that is independent of production period assumptions.

Methods

We consider ILUC in two forms. The first is called “accelerated expansion” and concerns ILUC in regions with an expanding agricultural area. The second is called “delayed reversion” and concerns ILUC in regions with a decreasing agricultural area. We use recent trends in international land use and projections of future land use change to assess how ILUC from biofuels will alter the development in global agricultural land use dynamics compared to the existing trend (i.e., the baseline development). We then use the definition of the global warming potential to determine the CO2 equivalence of the change in land use dynamics.

Results and discussion

We apply baseline time accounting to two existing ILUC studies in the literature. With current trends in global agricultural land use, the method significantly reduces the estimated climate impact in the previous ILUC studies (by more than half). Sensitivity analyses show that results are somewhat sensitive to assumptions regarding carbon sequestration and assumptions regarding postreversion ecosystems.

Conclusions

The global dynamic development in land use has important implications for the time accounting step when estimating the climate impact of ILUC caused by biofuel production or other issues affecting land use. Ignoring this may lead to erroneous conclusions about the actual climate impact of ILUC. Several land use projections indicate that the global agricultural area will keep expanding up to and beyond 2050. We therefore recommend to apply the baseline time accounting concept as an integrated part of future ILUC studies and to update the results on a regular basis.  相似文献   
57.
In the dinoflagellate Gonyaulax polyedra, bioluminescence is known to be controlled by proton transfer from an acidic vacuole system to the scintillons. We demonstrate that bafilomycin A 1, a specific blocker of V-type proton ATPases, inhibits at low concentrations (down to 2 × 10 –8 M) bioluminescence and, in particular, the circadian glow maximum. For many hours bafilomycin A 1 does not interfere with the capacity of the bioluminescent system. Therefore, we conclude on the participation of a V-type ATPase in proton accumulation in the acidic vacuoles. Inhibition of tryptophan hydroxylase by p-chlorophenylalanine, p-fluorophenylalanine, or 5-fluorotryptophan also suppresses the circadian glow maximum. After inhibition of the enzyme by p-chlorophenylalanine, the glow peak can be restored, without any additional unspecific effects on bioluminescence, by supplementation with 5-hydroxytryptophan. Therefore, the availability of indoleamines is required for the expression of the glow maximum. Since 5-methoxytryptamine is the only physiologically occurring indoleamine with substantial effects on bioluminescence at low concentrations (below 10 –7 M), and since this substance accumulates in the second half of the night to stimulatory concentrations, this indolic metabolite may represent the physiologically active substance involved in the expression of the glow maximum.  相似文献   
58.
Celiac disease (CD) is a gluten-responsive, chronic inflammatory enteropathy. IL-1 cytokine family members IL-1β and IL-18 have been associated with the inflammatory conditions in CD patients. However, the mechanisms of IL-1 molecule activation in CD have not yet been elucidated. We show in this study that peripheral blood mononuclear cells (PBMC) and monocytes from celiac patients responded to pepsin digest of wheat gliadin fraction (PDWGF) by a robust secretion of IL-1β and IL-1α and a slightly elevated production of IL-18. The analysis of the upstream mechanisms underlying PDWGF-induced IL-1β production in celiac PBMC show that PDWGF-induced de novo pro-IL-1β synthesis, followed by a caspase-1 dependent processing and the secretion of mature IL-1β. This was promoted by K+ efflux and oxidative stress, and was independent of P2X7 receptor signaling. The PDWGF-induced IL-1β release was dependent on Nod-like receptor family containing pyrin domain 3 (NLRP3) and apoptosis-associated speck like protein (ASC) as shown by stimulation of bone marrow derived dendritic cells (BMDC) from NLRP3−/− and ASC−/− knockout mice. Moreover, treatment of human PBMC as well as MyD88−/− and Toll-interleukin-1 receptor domain-containing adaptor-inducing interferon-β (TRIF)−/− BMDC illustrated that prior to the activation of caspase-1, the PDWGF-triggered signal constitutes the activation of the MyD88/TRIF/MAPK/NF-κB pathway. Moreover, our results indicate that the combined action of TLR2 and TLR4 may be required for optimal induction of IL-1β in response to PDWGF. Thus, innate immune pathways, such as TLR2/4/MyD88/TRIF/MAPK/NF-κB and an NLRP3 inflammasome activation are involved in wheat proteins signaling and may play an important role in the pathogenesis of CD.  相似文献   
59.

Objective:

A spontaneous deletion in the nicotinamide nucleotide transhydrogenase (Nnt) gene eliminating exons 7‐11 in C57BL/6J (B6J) mice is associated with reduced glucose‐stimulated insulin secretion in vitro, impaired glucose tolerance, higher epigonadal fat mass, and altered susceptibility to diet induced obesity of male B6J mice was proposed. A potential implication for NNT in human adipose tissue distribution has not been investigated so far.

Design and Methods:

Therefore, NNT mRNA expression in paired human samples of visceral (vis) and subcutaneous (sc) adipose tissue from 221 subjects with a wide range of body mass index (BMI), insulin sensitivity, and glucose tolerance was analyzed.

Results:

NNT mRNA expression is significantly higher in visceral fat of obese patients and correlates with body weight, BMI, % body fat, visceral and sc fat area, waist and hip circumference, and fasting plasma insulin (FPI). Multivariate linear regression analysis revealed visceral NNT expression as age and gender independent predictor of BMI, waist circumference, visceral fat area, and % body fat, but not FPI and 2 h OGTT glucose.

Conclusion:

In conclusion, a functional relevance of NNT in the development of human obesity and visceral fat distribution was suggested here.  相似文献   
60.
Alpine ecosystems are seriously threatened by climate change. One of the key mechanisms by which plants can adapt to changing environmental conditions is through evolutionary change. However, we still know little about the evolutionary potential in wild populations of long‐lived alpine plants. Here, we investigated heritabilities of phenological traits, leaf size, and performance traits in natural populations of the long‐lived alpine dwarf shrub Salix herbacea using relatedness estimates inferred from SSR (Simple Sequence Repeat) markers. Salix herbacea occurs in early‐ and late‐snowmelt microhabitats (ridges and snowbeds), and we assessed how performance consequences of phenological traits and leaf size differ between these microhabitats in order to infer potential for evolutionary responses. Salix herbacea showed low, but significant, heritabilities of leaf size, clonal and sexual reproduction, and moderate heritabilities of phenological traits. In both microhabitats, we found that larger leaves, longer intervals between snowmelt and leaf expansion, and longer GDD (growing‐degree days) until leaf expansion resulted in a stronger increase in the number of stems (clonal reproduction). In snowbeds, clonal reproduction increased with a shorter GDD until flowering, while the opposite was found on ridges. Furthermore, the proportion of flowering stems increased with GDD until flowering in both microhabitats. Our results suggest that the presence of significant heritable variation in morphology and phenology might help S. herbacea to adapt to changing environmental conditions. However, it remains to be seen if the rate of such an evolutionary response can keep pace with the rapid rate of climate change.  相似文献   
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