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71.
The synthesis and biological evaluation of novel antagonists of the rat H(3) receptor are described. These compounds differ from prototypical H(3) antagonists in that they do not contain an imidazole moiety, but rather a substituted aminopyrrolidine moiety. A systematic modification of the substituents on the aminopyrrolidine ring was performed using pre-formatted precursor sets, where applicable, to afford several compounds with high affinity and selectivity for the H(3) receptor.  相似文献   
72.
The purpose of this investigation was to assess the effects of training and tapering at the same time of the day on the diurnal variations of short exercise performances. Thirty-one physically active men underwent 12 weeks of lower-extremity resistance training and 2 weeks of tapering. These subjects were matched and randomly assigned to a morning training group (MTG, training times 0700-0800 hours, n = 10), an evening training group (ETG, training times 1700-1800 hours, n = 11), and a control group (CG, completed all tests but did not train, n = 10). Muscular strength and power testing was conducted before (T0) and after 12 weeks of training (T1) and after 2 weeks of tapering (T2) in the morning (0700-0800 hours) and in the evening (1700-1800 hours). All morning and evening tests were performed in separate sessions (minimum interval = 36 hours) in a randomized design. In T0, the oral temperature and performances during the Wingate, vertical jump (squat jump and countermovement jump), and maximal voluntary contraction tests were higher in the evening than in the morning for all the groups. In T1, these diurnal variations were blunted in the MTG and persisted in the ETG and CG. In T2, the 2 weeks of tapering resulted in further time of day-specific adaptations and increases in short-term maximal performances. However, there was no significant difference in the relative increase between the MTG and the ETG after both training and tapering. From a practical point of view, if the time of competition is known, training and tapering sessions before a major competition must be conducted at the same time of the day at which one's critical performance is programmed. Moreover, if the time of the competition is not known, a tapering phase after resistance training program could be performed at any time of the day with the same benefit.  相似文献   
73.
The aim of this study was to examine the effects of training at the same time of the day on the diurnal variations of anaerobic performances to provide some recommendations to adjust training hours with the time of the day of competitive events. Thirty participants underwent 8 weeks of lower-extremity progressive resistance training performed 3 times per week designed to promote muscular strength and power. These subjects were randomly assigned to a morning training group (MTG, 07:00-08:00 hours, n = 10), an evening training group (ETG, 17:00-18:00 hours, n = 10), and a control group (CG, completed all tests but did not train, n = 10). Performance in the squat jump, the countermovement jump, the Wingate and 1 repetition maximum (1RM) during leg extension, leg curl, and squat tests was recorded just before and 2 weeks after an 8-week course of regular training. For all the subjects, the morning and evening tests were scheduled at the same time of the day as for the morning and evening training sessions. Before training, the results indicated a significant increase in performance from morning to evening tests (ca. 2.84-17.55% for all tests) for all groups. After training, the diurnal variations in anaerobic performances were blunted in the MTG. In fact, there was no significant difference in muscular power or strength between morning and evening tests. However, these intradaily variations in anaerobic performances persisted in the ETG and CG. From a practical point of view, adaptation to strength training is greater at the time of the day at which training was scheduled than at other times.  相似文献   
74.
Although recognized as effective measures to curb the spread of the COVID19 outbreak, social distancing and home confinement have generated a mental health burden with older adults who are considered to be more vulnerable to psychosocial strains. To date, the application of digital technologies in response to COVID-19 pandemic has been narrowed to public-health needs related to containment and mitigation. However, information and communications technology (ICT)-based initiatives directed toward prediction and prevention of psychosocial support are still limited. Given the power of digital health solutions to allow easy and accurate characterization and intervention for health and disease, as well as to flatten the COVID19 incidence curves in many countries, our ECLB-COVID19 consortium is highlighting the importance of providing innovative ICT-based solutions (ICT-COVID-Companion) to improve elderly physical and mental health, thereby preventing/dampening psychosocial strain during pandemics. Based on innovative approaches (e.g., emotional/social computing, open social platform, interactive coaching, gamification, fitness-tracker, internet of things) and smart digital solutions (smartwatch/smartphone), smart companions must provide safe personalised physical, mental and psychosocial health surveillance. Additionally, by delivering personalised multi-dimension crisis-oriented health recommendations, such innovative crisis-oriented solutions would help (i) facilitate a user’s adherence to active and healthy confinement lifestyle (AHCL), (ii) achieve a rapid psychosocial recovery in case of depression issues and (iii) enhance preparedness for eventual future pandemics.  相似文献   
75.
Biometric study of the inner features of Heterostegina specimens preserved in tortonian sediments of the oued Yhoudi member allows to confirm the presence of species Heterostegina papyracea Seguenza, 1880. Analysis of both large and small components of the foraminiferal assemblage in all examined samples establishes the dominant character of species Heterostegina papyracea Seguenza (more than 60% of total benthic foraminifera). The assemblage of small benthic foraminifera associated with the Heterostegina is different from that described from Recent sediments, as well as from Miocene sediments of Calabria and Spain. In order to explain this result, two hypotheses can be put forward: (1) the Tortonian Heterostegina from Morocco proliferated abundantly in very shallow environments in association with small foraminifera (i.e. abundant Ammonia beccarii). (2) Because of powerful tidal currents in the South Rifian Corridor, Heterostegina tests were probably transferred after death. This transfer could possibly be due to the narrowness of the South Rifian Corridor in the Early Late Tortonian and its position between the Atlantic and the Mediterranean. Similar cases foraminiferal displacements are also known from modern basins. This study illustrates the difficulties in reconstructing the paleogeography of the studied area and the importance of considering all available components of the assemblage.  相似文献   
76.
Blockade of presynaptic histamine H(3) receptors with potent and selective ligands improves cognitive function in rodents and there is significant interest in developing such drugs for long-term symptomatic treatment of CNS disorders such as attention deficit hyperactivity disorder (ADHD). Unfortunately, little is known about the effects of repeated exposure to H(3) receptor antagonists/inverse agonists. We therefore investigated the effects of acute and repeated daily administration of two potent, brain penetrating H(3) receptor antagonists/inverse agonists, ciproxifan and A-304121, on rat body weight, food and water intake, core temperature and locomotor activity, as well as H(3) receptor density and gene expression levels. Methylphenidate, used clinically for the treatment of ADHD, was included as an additional comparator. Ciproxifan, an imidazole-based compound, decreased food intake over the first 10 days and locomotor activity acutely, but these effects were lost after further repeated administration. The ex vivo binding studies revealed increased H(3) receptor density in rats following repeated administration of ciproxifan for 10 or 15 days; however, H(3) receptor gene expression was not changed. In contrast, rats treated with the non-imidazole, A-304121, did not differ from controls on any measure during the observation period, while rats treated with methylphenidate exhibited hyperthermia and hyperactivity. The implications for potential long-term treatment with H(3) receptor antagonists in CNS disorders such as ADHD are discussed.  相似文献   
77.
Qualitative and quantitative analyses of planktonic foraminifera (completed by calcareous nannofossils in some localities) from 8 sections and boreholes located in 7 Neogene basins of the South Rifian Corridor (Morocco) enable us to identify 16 bioevents calibrated with the geomagnetic polarity time scale. These events are useful for (1) assigning the sediments to the Tortonian (bioevents 1 to 7), the Messinian (bioevents 9 to 14, the event 8 indicates the Tortonian/Messinian boundary), the Early Pliocene (bioevent 15) and the Middle Pliocene (bioevent 16), (2) establishing high resolution correlations between the sections and boreholes studied herein, (3) locating the South Rifian Corridor sections and boreholes within the framework of biostratigraphic events recognized during the latest ten years in time-equivalent Atlantic and Mediterranean sequences, and (4) estimating the variation of sedimentation rates in the studied basins. With respect to Morocco, previous detailed studies concerned only the Rabat area (Bou Regreg valley) and Guercif basin. Our results extend correlations to the other basins of the South Rifian Corridor, a key area to understand connections between the Atlantic Ocean and the Mediterranean Sea at the end of the Miocene.  相似文献   
78.
Activated human neuropeptide Y Y(1) receptors rapidly desensitize and internalize through clathrin-coated pits and recycle from early and recycling endosomes, unlike Y(2) receptors that neither internalize nor desensitize. To identify motifs implicated in Y(1) receptor desensitization and trafficking, mutants with varying C-terminal truncations or a substituted Y(2) C-terminus were constructed. Point mutations of key putative residues were made in a C-terminal conserved motif [phi-H-(S/T)-(E/D)-V-(S/T)-X-T] that we have identified and in the second intracellular i2 loop. Receptors were analyzed by functional assays, spectrofluorimetric measurements on living cells, flow cytometry, confocal imaging and bioluminescence resonance energy transfer assays for beta-arrestin activation and adaptor protein (AP-2) complex recruitment. Inhibitory GTP-binding protein-dependent signaling of Y(1) receptors to adenylyl cyclase and desensitization was unaffected by C-terminal truncations or mutations, while C-terminal deletion mutants of 42 and 61 amino acids no longer internalized. Substitutions of Thr357, Asp358, Ser360 and Thr362 by Ala in the C-terminus abolished both internalization and beta-arrestin activation but not desensitization. A Pro145 substitution by His in an i2 consensus motif reported to mediate phosphorylation-independent recruitment of beta-arrestins affected neither desensitization, internalization or recycling kinetics of activated Y(1) receptors nor beta-arrestin activation. Interestingly, combining Pro145 substitution by His and C-terminal substitutions significantly attenuates Y(1) desensitization. In the Y(2) receptor, replacement of His155 with Pro at this position in the i2 loop motif promotes agonist-mediated desensitization, beta-arrestin activation, internalization and recycling. Overall, our results indicate that beta-arrestin-mediated desensitization and internalization of Y(1) and Y(2) receptors are differentially regulated by the C-terminal motif and the i2 loop consensus motif.  相似文献   
79.

Background

Neutrophils play a major role in inflammation by releasing large amounts of ROS produced by NADPH-oxidase and myeloperoxidase (MPO). The proinflammatory cytokine TNFα primes ROS production through phosphorylation of the NADPH-oxidase subunit p47phox on Ser345. Conventional anti-inflammatory therapies remain partially successful and may have side effects. Therefore, regulation of neutrophil activation by natural dietary components represents an alternative therapeutic strategy in inflammatory diseases such as inflammatory bowel diseases. The aim of this study was to assess the effect of punicic acid, a conjugated linolenic fatty acid from pomegranate seed oil on TNFα-induced neutrophil hyperactivation in vitro and on colon inflammation in vivo.

Methodology and Principal Findings

We analyzed the effect of punicic acid on TNFα-induced neutrophil upregulation of ROS production in vitro and on TNBS-induced rat colon inflammation. Results show that punicic acid inhibited TNFα-induced priming of ROS production in vitro while preserving formyl-methionyl-leucyl-phenylalanine (fMLP)-induced response. This effect was mediated by the inhibition of Ser345-p47phox phosphorylation and upstream kinase p38MAPK. Punicic acid also inhibited fMLP- and TNFα+fMLP-induced MPO extracellular release from neutrophils. In vivo experiments showed that punicic acid and pomegranate seed oil intake decreased neutrophil-activation and ROS/MPO-mediated tissue damage as measured by F2-isoprostane release and protected rats from TNBS-induced colon inflammation.

Conclusions/Significance

These data show that punicic acid exerts a potent anti-inflammatory effect through inhibition of TNFα-induced priming of NADPH oxidase by targeting the p38MAPKinase/Ser345-p47phox-axis and MPO release. This natural dietary compound may provide a novel alternative therapeutic strategy in inflammatory diseases such as inflammatory bowel diseases.  相似文献   
80.
Although ezrin-radixin-moesin-binding phosphoprotein 50 (EBP50) is a PDZ domain-containing protein known to bind to various channels, receptors, cytoskeletal elements, and cytoplasmic proteins, there is still very little evidence for a role of EBP50 in the regulation of receptor signal transduction. In this report, we show that EBP50 inhibits the phospholipase C (PLC)-beta-mediated inositol phosphate production of a Galpha(q)-coupled receptor as well as PLC-beta activation by the constitutively active Galpha(q)-R183C mutant. Coimmunoprecipitation experiments revealed that EBP50 interacts with Galpha(q) and to a greater extent with Galpha(q)-R183C. Agonist stimulation of the thromboxane A(2) receptor (TP receptor) resulted in an increased interaction between EBP50 and Galpha(q), suggesting that EBP50 preferentially interacts with activated Galpha(q). We also demonstrate that EBP50 inhibits Galpha(q) signaling by preventing the interaction between Galpha(q) and the TP receptor and between activated Galpha(q) and PLC-beta1. Investigation of the EBP50 regions involved in Galpha(q) binding indicated that its two PDZ domains are responsible for this interaction. This study constitutes the first demonstration of an interaction between a G protein alpha subunit and another protein through a PDZ domain, with broad implications in the regulation of diverse physiological systems.  相似文献   
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