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231.
Tiger beetles are a remarkable group that captivates amateur entomologists, taxonomists and evolutionary biologists alike. This diverse clade of beetles comprises about 2300 currently described species found across the globe. Despite the charisma and scientific interest of this lineage, remarkably few studies have examined its phylogenetic relationships with large taxon sampling. Prior phylogenetic studies have focused on relationships within cicindeline tribes or genera, and none of the studies have included sufficient taxon sampling to conclusively examine broad species patterns across the entire subfamily. Studies that have attempted to reconstruct higher‐level relationships of Cicindelinae have yielded conflicting results. Here, we present the first taxonomically comprehensive molecular phylogeny of Cicindelinae to date, with the goal of creating a framework for future studies focusing on this important insect lineage. We utilized all available published molecular data, generating a final concatenated dataset including 328 cicindeline species, with molecular data sampled from six protein‐coding gene fragments and three ribosomal gene fragments. Our maximum‐likelihood phylogenetic inferences recover Cicindelinae as sister to the wrinkled bark beetles of the subfamily Rhysodinae. This new phylogenetic hypothesis for Cicindelinae contradicts our current understanding of tiger beetle phylogenetic relationships, with several tribes, subtribes and genera being inferred as paraphyletic. Most notably, the tribe Manticorini is recovered nested within Platychilini including the genera Amblycheila Say, Omus Eschscholtz, Picnochile Motschulsky and Platychile Macleay. The tribe Megacephalini is recovered as paraphyletic due to the placement of the monophyletic subtribe Oxycheilina as sister to Cicindelini, whereas the monophyletic Megacephalina is inferred as sister to Oxycheilina, Cicindelini and Collyridini. The tribe Collyridini is paraphyletic with the subtribes Collyridina and Tricondylina in one clade, and Ctenostomina in a second one. The tribe Cicindelini is recovered as monophyletic although several genera are inferred as para‐ or polyphyletic. Our results provide a novel phylogenetic framework to revise the classification of tiger beetles and to encourage the generation of focused molecular datasets that will permit investigation of the evolutionary history of this lineage through space and time.  相似文献   
232.
A K141N missense mutation in heat shock protein (HSP) B8, which belongs to the small HSP family, causes distal hereditary motor neuropathy, which is characterized by the formation of inclusion bodies in cells. Although the HSPB8 gene causes hereditary motor neuropathy, obvious expression of HSPB8 is also observed in other tissues, such as the heart. The effects of a single mutation in HSPB8 upon the heart were analyzed using rat neonatal cardiomyocytes. Expression of HSPB8 K141N by adenoviral infection resulted in increased HSPB8-positive aggregates around nuclei, whereas no aggregates were observed in myocytes expressing wild-type HSPB8. HSPB8-positive aggresomes contained amyloid oligomer intermediates that were detected by a specific anti-oligomer antibody (A11). Expression of HSPB8 K141N induced slight cellular toxicity. Recombinant HSPB8 K141N protein showed reactivity against the anti-oligomer antibody, and reactivity of the mutant HSPB8 protein was much higher than that of wild-type HSPB8 protein. To extend our in vitro study, cardiac-specific HSPB8 K141N transgenic (TG) mice were generated. Echocardiography revealed that the HSPB8 K141N TG mice exhibited mild hypertrophy and apical fibrosis as well as slightly reduced cardiac function, although no phenotype was detected in wild-type HSPB8 TG mice. A single point mutation of HSPB8, such as K141N, can cause cardiac disease.  相似文献   
233.
Under anaerobic conditions, Escherichia coli produces succinate from glucose via the reductive tricarboxylic acid cycle. To date, however, no genes encoding succinate exporters have been established in E. coli. Therefore, we attempted to identify genes encoding succinate exporters by screening an E. coli MG1655 genome library. We identified the yjjPB genes as candidates encoding a succinate transporter, which enhanced succinate production in Pantoea ananatis under aerobic conditions. A complementation assay conducted in Corynebacterium glutamicum strain AJ110655ΔsucE1 demonstrated that both YjjP and YjjB are required for the restoration of succinate production. Furthermore, deletion of yjjPB decreased succinate production in E. coli by 70% under anaerobic conditions. Taken together, these results suggest that YjjPB constitutes a succinate transporter in E. coli and that the products of both genes are required for succinate export.  相似文献   
234.
The present clinical trials revealed that 16,16-Dimethyl-trans-δ2-PGE1 methyl ester in the form of vaginal suppositories is highly effective in inducing mid-trimester termination of pregnancies. It also showed that prior treatment with laminaria and metreurynter may enhance the success rate while reducing the incidence and severity of side effects. It is easy and safe to use clinically, with minimal side effects, and in our series, revealed no deleterious effects on ensuing reproductive physiology. However, the definite mechanism involved in the action of this new analogue to cause myometrial contractions is still not completely understood, and requires further intensive investigation.  相似文献   
235.
The existence of antibodies to nonenzymatically glucosylated albumin was investigated in nondiabetic and diabetic subjects. The sera from both the nondiabetic and the diabetic subjects were shown to contain the proteins which bound to reductively glucosylated albumin. An enzyme-linked immunosorbent assay demonstrated that the antibodies specific for reductively glucosylated albumin existed in the sera containing the binding proteins. For binding the antibodies glucitollysine as the glucose adduct in reductively glucosylated albumin was an effective competitor. The hexose alcohol epimers glucitol and mannitol were also effective competitors compatible with glucitollysine. Our results suggest that the antibodies to reductively glucosylated albumin are widely present not only in the diabetic subjects but also in the nondiabetic subjects and cross-react with the hexose alcohol.  相似文献   
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237.
A moderately thermophilic bacterial strain, Meiothermus ruber H328, can efficiently solubilize intact chicken feathers by aerobic cultivation at 55 °C for 6 days. The keratinolytic proteases extracellularly secreted by the strain were partially purified by an ultrafiltration system and a size-exclusion column chromatography, and thus were found to be two different sizes of macromolecules with an extremely high molecular mass like the sizes of virus and DNA (peak 1 fraction) and with a molecular mass of larger than 500 kDa (peak 2 fraction). They formed protein complex assemblies that were composed of multiple but different proteins. The peak 1 fraction showed more thermophilic characteristics than did the peak 2 fraction in temperature dependence and thermal stability. By contrast, they comparably showed extraordinary resistance to powerful denaturants, SDS at 30 % (w/v) and organic solvents (methanol, ethanol, acetonitrile, acetone, and chloroform) at 40 % (v/v) at 60 °C for 30 min. The extraordinary denaturant tolerance and the large molecular size of the keratinolytic protease complex assemblies suggest the possibility that those may be lipophilic and have the structure of partial membrane fractions, or membrane vesicles, which are exfoliated from the outer membrane of the cells.  相似文献   
238.
The utility of various synthetic peptides has been investigated in clinical trials of the treatment of cancers, infectious diseases and endocrine diseases. In the process of functional gene screening with in silico analysis for molecules with angiogenic properties, we generated a small peptide, angiogenic peptide (AG)-30, that possesses both antimicrobial and pro-inflammatory activities. AG-30 has an α-helix structure with a number of hydrophobic or net positively charged amino acids and a propensity to fold into amphipathic structures. Indeed, AG-30 exhibited antimicrobial activity against various bacteria, induced vascular endothelial cell growth and tube formation in a dose-dependent manner and increased neovascularization in a Matrigel plug assay. As a result, AG-30 up-regulated expression of angiogenesis-related cytokines and growth factors for up to 72 hrs in human aortic endothelial cells. To further evaluate the angiogenic effect of AG-30 in vivo , we developed a slow-release AG-30 system utilizing biodegradable gelatin microspheres. In the ischaemic mouse hind limb, slow-release AG-30 treatment results in an increase in angiogenic score, an increase in blood flow (as demonstrated by laser Doppler imaging) and an increase in capillary density (as demonstrated by immunostaining with anti-CD31 antibody). These data suggest that the novel peptide, AG-30, may have therapeutic potential for ischaemic diseases.  相似文献   
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240.
Glucokinase (GK) plays a key role in the control of blood glucose homeostasis. We identified a small molecule GK activator, compound A, that increased the glucose affinity and maximal velocity (V(max)) of GK. Compound A augmented insulin secretion from isolated rat islets and enhanced glucose utilization in primary cultured rat hepatocytes. In rat oral glucose tolerance tests, orally administrated compound A lowered plasma glucose elevation with a concomitant increase in plasma insulin and hepatic glycogen. In liver, GK activity is acutely controlled by its association to the glucokinase regulatory protein (GKRP). In order to decipher the molecular aspects of how GK activator affects the shuttling of GK between nucleus and cytoplasm, the effect of compound A on GK-GKRP interaction was further investigated. Compound A increased the level of cytoplasmic GK in both isolated rat primary hepatocytes and the liver tissues from rats. Experiments in a cell-free system revealed that compound A interacted with glucose-bound free GK, thereby impairing the association of GK and GKRP. On the other hand, compound A did not bind to glucose-unbound GK or GKRP-associated GK. Furthermore, we found that glucose-dependent GK-GKRP interaction also required ATP. Given the combined prominent role of GK on insulin secretion and hepatic glucose metabolism where the GK-GKRP mechanism is involved, activation of GK has a new therapeutic potential in the treatment of type 2 diabetes.  相似文献   
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