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101.
New records of Cynipid gall wasps and inquilines for the Italian peninsula and Sicily and their new host plants for the Palaearctic Region are listed and commented on. Among them we find: Cerroneuroterus cerrifloralis (Müllner 1901) as new for Italy and new for the Palaearctic region as host on Quercus suber; Andricus multiplicatus Giraud 1859 on Q. suber, as new host for the Palaearctic region; Aylax papaveris (Perris 1839), reported in Italy over a century ago, but later overlooked; Cerroneuroterus minutulus (Giraud 1859), also reported more than a century ago from Sicily, but later overlooked. Among the inquilines are here listed: Synergus variabilis Mayr 1872, emerged from Janetia cerris (Kollar 1850) galls (Diptera Cecidomyiidae), and found for the first time in the Palaearctic Region as host on Q. suber; Saphonecrus haimi (Mayr 1872) and Saphonecrus barbotini Pujade-Villar & Nieves-Aldrey 1986, are new records for Italy.  相似文献   
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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   
104.
Helminth parasites are masters of immune regulation; a likely prerequisite for long-term survival by circumventing their hosts’ attempt to eradicate them. From a translational perspective, knowledge of immune events as a response to infection with a helminth parasite could be used to reduce the intensity of unwanted inflammatory reactions. Substantial data have accumulated showing that inflammatory reactions that promote a variety of auto-inflammatory diseases are dampened as a consequence of infection with helminth parasites, via either the mobilization of an anti-worm spectrum of immune events or by the direct effect of secretory/excretory bioactive immunomodulatory molecules released from the parasite. However, many issues are outstanding in the definition of the mechanism(s) by which infection with helminth parasites can affect the outcome, positively or negatively, of concomitant disease. We focus on a subgroup of this complex group of metazoan parasites, the cestodes, summarizing studies from rodent models that illustrate if, and by what mechanisms, infection with tapeworms ameliorate or exaggerate disease in their host. The ability of infection with cestodes, or other classes of helminth, to worsen a disease course or confer susceptibility to intracellular pathogens should be carefully considered in the context of ‘helminth therapy’. In addition, poorly characterised cestode extracts can regulate murine and human immunocyte function, yet the impact of these in the context of autoimmune or allergic diseases is poorly understood. Thus, studies with cestodes, as representative helminths, have helped cement the concept that infection with parasitic helminths can inhibit concomitant disease; however, issues relating to long-term effects, potential side-effects, mixed pathogen infections and purification of immunomodulatory molecules from the parasite remain as challenges that need to be addressed in order to achieve the use of helminths as anti-inflammatory agents for human diseases.  相似文献   
105.
Light‐harvesting complex II (LHCII) contains three highly homologous chlorophyll‐a/b‐binding proteins (Lhcb1, Lhcb2 and Lhcb3), which can be assembled into both homo‐ and heterotrimers. Lhcb1 and Lhcb2 are reversibly phosphorylated by the action of STN7 kinase and PPH1/TAP38 phosphatase in the so‐called state‐transition process. We have developed antibodies that are specific for the phosphorylated forms of Lhcb1 and Lhcb2. We found that Lhcb2 is more rapidly phosphorylated than Lhcb1: 10 sec of ‘state 2 light’ results in Lhcb2 phosphorylation to 30% of the maximum level. Phosphorylated and non‐phosphorylated forms of the proteins showed no difference in electrophoretic mobility and dephosphorylation kinetics did not differ between the two proteins. In state 2, most of the phosphorylated forms of Lhcb1 and Lhcb2 were present in super‐ and mega‐complexes that comprised both photosystem (PS)I and PSII, and the state 2‐specific PSI–LHCII complex was highly enriched in the phosphorylated forms of Lhcb2. Our results imply distinct and specific roles for Lhcb1 and Lhcb2 in the regulation of photosynthetic light harvesting.  相似文献   
106.
New compounds containing a novel zinc binding group (salicylaldoxime system) were identified as effective inhibitors of carbonic anhydrases (CAs). This structural motif seems to bind the catalytic zinc ion of CAs, revealing itself as a new valid alternative to the sulfonamide group. Computational procedures were used to investigate the binding mode of this class of compounds, within the active site of CAII. This study suggests that the salicylaldoxime moiety binds the zinc ion through the oxime oxygen atom that also forms an H-bond with T199. The results herein obtained will allow the development of new CA-inhibitors bearing the salicylaldoxime moiety.  相似文献   
107.
Increasing evidence reveals a large dependency of epithelial cancer cells on oxidative phosphorylation (OXPHOS) for energy production. In this study we tested the potential of epigallocatechin-3-gallate (EGCG), a natural polyphenol known to target mitochondria, in inducing OXPHOS impairment and cell energy deficit in human epitheliod (REN cells) and biphasic (MSTO-211H cells) malignant pleural mesothelioma (MMe), a rare but highly aggressive tumor with high unmet need for treatment. Due to EGCG instability that causes H2O2 formation in culture medium, the drug was added to MMe cells in the presence of exogenous superoxide dismutase and catalase, already proved to stabilize the EGCG molecule and prevent EGCG-dependent reactive oxygen species formation. We show that under these experimental conditions, EGCG causes the selective arrest of MMe cell growth with respect to normal mesothelial cells and the induction of mitochondria-mediated apoptosis, as revealed by early mitochondrial ultrastructure modification, swelling and cytochrome c release. We disclose a novel mechanism by which EGCG induces apoptosis through the impairment of mitochondrial respiratory chain complexes, particularly of complex I, II and ATP synthase. This induces a strong reduction in ATP production by OXPHOS, that is not adequately counterbalanced by glycolytic shift, resulting in cell energy deficit, cell cycle arrest and apoptosis. The EGCG-dependent negative modulation of mitochondrial energy metabolism, selective for cancer cells, gives an important input for the development of novel pharmacological strategies for MMe.  相似文献   
108.
Glioblastoma multiforme (GBM) is the most lethal and common malignant human brain tumor. The intrinsic resistance of highly invasive GBM cells to radiation- and chemotherapy-induced apoptosis accounts for the generally dismal treatment outcomes. This study investigated ophiobolin A (OP-A), a fungal metabolite from Bipolaris species, for its promising anticancer activity against human GBM cells exhibiting varying degrees of resistance to proapoptotic stimuli. We found that OP-A induced marked changes in the dynamic organization of the F-actin cytoskeleton, and inhibited the proliferation and migration of GBM cells, likely by inhibiting big conductance Ca2+-activated K+ channel (BKCa) channel activity. Moreover, our results indicated that OP-A induced paraptosis-like cell death in GBM cells, which correlated with the vacuolization, possibly brought about by the swelling and fusion of mitochondria and/or the endoplasmic reticulum (ER). In addition, the OP-A-induced cell death did not involve the activation of caspases. We also showed that the expression of BKCa channels colocalized with these two organelles (mitochondria and ER) was affected in this programmed cell death pathway. Thus, this study reveals a novel mechanism of action associated with the anticancer effects of OP-A, which involves the induction of paraptosis through the disruption of internal potassium ion homeostasis. Our findings offer a promising therapeutic strategy to overcome the intrinsic resistance of GBM cells to proapoptotic stimuli.  相似文献   
109.
110.
The Staphylococcus aureus regulatory saePQRS system controls the expression of numerous virulence factors, including extracellular adherence protein (Eap), which amongst others facilitates invasion of host cells. The saePQRS operon codes for 4 proteins: the histidine kinase SaeS, the response regulator SaeR, the lipoprotein SaeP and the transmembrane protein SaeQ. S. aureus strain Newman has a single amino acid substitution in the transmembrane domain of SaeS (L18P) which results in constitutive kinase activity. SDS was shown to be one of the signals interfering with SaeS activity leading to inhibition of the sae target gene eap in strains with SaeSL but causing activation in strains containing SaeSP. Here, we analyzed the possible involvement of the SaeP protein and saePQ region in SDS-mediated sae/eap expression. We found that SaePQ is not needed for SDS-mediated SaeS signaling. Furthermore, we could show that SaeS activity is closely linked to the expression of Eap and the capacity to invade host cells in a number of clinical isolates. This suggests that SaeS activity might be directly modulated by structurally non-complex environmental signals, as SDS, which possibly altering its kinase/phosphatase activity.  相似文献   
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