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1.
本文应用电力载波技术,实现远端时钟的中央控制。系统通过电力载波芯片从电力线上收发控制信号,中央控制端发送的时钟校准信号到电力线网络,接人网络的远端时钟接收到校准信号后,由微处理器解析数据调整受控端时钟显示,从而实现时钟的中央控制。 相似文献
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Nika Adham Laurence A. Borden Lee E. Schechter Eric L. Gustafson Tamara L. Cochran Pierrre J.-J. Vaysse Richard L. Weinshank Theresa A. Branchek 《Naunyn-Schmiedeberg's archives of pharmacology》1993,348(6):566-575
We recently described the cloning of a fifth member of the 5-hydroxytryptamine (5-HT)1 (serotonin1) receptor class that inhibits adenylyl cyclase, namely the human 5-HT1F receptor (Adham et al. 1993 a). In the present study we have examined in greater detail the functional coupling of the 5-HT1F receptor in two different cell lines, NIH-3T3 and LM(tk–) fibroblasts (receptor densities of 1.7 and 4.4 pmol/mg protein, respectively). The maximal inhibitory response elicited by 5-HT was significantly greater in NIH-3T3 as compared to LM(tk–) cells, whereas the EC50 values were comparable.To investigate the relationship between receptor occupancy and inhibition of cAMP accumulation mediated by 5-HT1F receptors in NIH-3T3 cells (and hence the degree of receptor reserve), we used the irreversible receptor antagonist N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ). The half-maximal response required only about 10% receptor occupancy, consistent with a receptor reserve of 90% (88±2.1%, n = 4) for 5-HT-induced inhibition of FSCA. Despite the presence of such a high degree of receptor reserve, a range of intrinsic activities was displayed by structurally diverse classes of compounds. For example, sumatriptan and lysergol were as efficacious as 5-HT itself and thus acted as full agonists, whereas metergoline and 1-NP behaved as partial agonists and as shown previously (Adham et al. 1993a), methiothepin was a silent antagonist (Kb = 438 nM).We have also investigated activation of additional signal transduction pathways by the 5-HT1F receptor and found that the responses differ in the two cell lines with respect to stimulation of phospholipase C. For example, in NIH-3T3 cells no elevation of inositol phosphates (IP) of [Ca2+]i was observed even at very high agonist concentrations (100 M). In contrast, in LM(tk–) cells concentrations of 5-HT as low as 10 nM induced stimulation of IP and a rapid increase of [Ca2+]i. The 5-HT1F receptor failed to alter arachidonic acid release in either cell line.The maximal increase in IP accumulation in LM(tk–) cells was modest, averaging about 100% above basal. The increases of IP and [Ca2+]i required 5-HT concentrations less than one order of magnitude greater than those inhibiting FSCA (EC50 = 17, 55 and 8 nM, respectively), and both responses were blocked by 100 M methiothepin. All three responses (cAMP, IP, and [Ca2+]i) were sensitive to pertussis toxin pre-treatment, suggesting the involvement of Gi/Go protein(s) in these signal transduction pathways. [Ca2+]i was also elevated by sumatriptan, which may provide a mechanism by which this drug causes constriction of the vasculature. In conclusion, these data indicate that the human 5-HT1F receptor can couple to multiple effectors, and that this coupling is cell-type dependent.Abbreviations FSCA
forskolin-stimulated cAMP accumulation
- [Ca2+]
intracellular free calcium concentration
- AA
arachidonic acid
- EEDQ
N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline
- CHO
chinese hamster ovary cell
- LM(tk–)
mouse fibroblast cell
- Bmax
maximal binding site density
- Ki
apparent dissociation constant obtained from competition binding studies
- G protein
guanine nucleotide-binding protein
- HBS
HEPES-buffered saline
- IP
inositol phosphates
- IP3
inositol 1,4,5 trisphosphate
- PLC
phospholipase C
- Kb
antagonist dissociation constant
- Kd
equilibrium dissociation constant
- N-1F-6
stable NIH-3T3 cells expressing the cloned 5-HT1F receptor
- L-1F-3
stable LM(tk–) cells expressing the cloned 5-HT1F receptor
- PTX
pertussis toxin
- BSA
bovine serum albumin
- METH
methiothepin
- SUMA
sumatriptan
- 5-MeO-DMT
5-methoxy-N,N-dimethyltryptamine
- 1-NP
1-(1-napthyl)piperazine
- 5-CT
5-carboxyamidotryptamine
Correspondence to: N. Adham at the above address 相似文献
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P. Fredman C. A. Vedeler H. Nyland J. A. Aarli L. Svennerholm 《Journal of neurology》1991,238(2):75-79
Summary Sera from 23 patients with acute Guillain Barré syndrome (GBS), 15 patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and from 40 age-matched blood donors were analysed for antibodies to acidic glycosphingolipids from human brain and peripheral nerve. Antibodies to ganglioside LM1, the major ganglioside of peripheral nerve myelin, were found in 43% of GBS and in 67% of CIDP patients' sera, and in 20% of the blood donors. However, anti-sulphatide antibodies were detected in 65% and 87% of the sera from GBS and CIDP patients, respectively, but only in 15% of the control sera. Sulphatide is the major acidic glycosphingolipid in myelin and its concentration in peripheral nerve myelin is 100 times higher than that of LM1. The high frequency of LM1 and, in particular of sulphatide antibodies, might thus be relevant to the pathogenesis of the GBS and CIDP.
Abbreviations: The ganglioside nomenclature used according to Svennerholm [24]. LM1, IV3NeuAc-nLcOse4Cer, GM1, II3NeuAcGgOse4Cer; GD1a, IV3NeAc,II3NeuAc-GgOse4Cer; GD1b, II3(NeuAc)2-GgOse4Cer; GT1b, IV3NeuAc,II3(NeuAc)2-GgOs4Cer; LU1, sulphate-3-glucuronyl paragloboside; sulphatide, 3-sulphogalacto-sylceramide 相似文献
6.
Summary This paper develops a specification test for functional form for models identified by a conditional moment restriction, including IV and GMM settings. The framework is one where the moment restriction is specified as a function of data, a finite‐dimensional parameter vector and a non‐parametric function (an infinite‐dimensional parameter vector). The null hypothesis is that the moment restriction does not depend on the non‐parametric function. The test is relatively easy to implement and its asymptotic distribution is known. The test performs well in simulation experiments. 相似文献
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Tae-Min Rhee Kyung Woo Park Chi-Hoon Kim Jeehoon Kang Jung-Kyu Han Han-Mo Yang Hyun-Jae Kang Bon-Kwon Koo Hyo-Soo Kim 《JACC: Cardiovascular Interventions》2018,11(24):2453-2463
Objectives
The aim of this study was to investigate clinical outcomes after left main coronary artery (LM) bifurcation percutaneous coronary intervention (PCI) and the impact of the duration of dual antiplatelet therapy (DAPT) according to treatment strategy.Background
There are limited data regarding the optimal PCI strategy for LM bifurcation lesions with new-generation drug-eluting stents.Methods
A patient-level pooled analysis of 5 nationwide multicenter registries was performed. Rates of target lesion failure, thrombotic adverse cardiovascular events, and their individual components at 3-year were analyzed. Subgroup analysis according to DAPT duration was performed.Results
From 13,172 patients undergoing PCI with new-generation drug-eluting stents, a total of 700 patients were treated for LM bifurcation lesions, 567 with a 1-stent strategy and 133 with a 2-stent strategy. Rates of target lesion failure and target lesion revascularization were higher in the 2-stent group, driven mainly by complex lesion profiles. Risks for thrombotic adverse cardiovascular events and its components were comparable between the 2 strategies. Subgroup analysis showed that risks for target lesion failure and thrombotic adverse cardiovascular events in the 2-stent group were significantly higher than in the 1-stent group in those with DAPT interruption <1 year, while they were similar in those receiving DAPT maintenance ≥1 year.Conclusions
Up to 20% of patients who underwent LM bifurcation PCI eventually required a 2-stent strategy, which was as safe as a 1-stent strategy with the use of new-generation drug-eluting stents. Careful pre-emptive case selection as well as prolonged DAPT may be necessary when considering a 2-stent strategy in LM PCI given its higher rate of repeat revascularization and lesion failure than the 1-stent approach. 相似文献9.
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《JACC: Cardiovascular Interventions》2014,7(10):1128-1137
ObjectivesThis study sought to evaluate the long-term prognostic capacity of the SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) score II (SS-II) and compare it with other risk scores among patients undergoing left main percutaneous coronary intervention (LM-PCI).BackgroundRecently, the SS-II was developed in an attempt to individualize and help the decision-making process between PCI and coronary artery bypass graft (CABG) surgery in the management of complex coronary artery disease (CAD). However, there is a paucity of data regarding the utility of SS-II in patients undergoing LM-PCI.MethodsData from 1,528 consecutive patients from a single center undergoing unprotected LM-PCI were prospectively collected. The SS-II and other scores were then derived using patients’ baseline clinical characteristics. Patients were stratified according to tertiles of SS-II for PCI: SS-II ≤21 (n = 508), SS-II >21 and ≤28 (n = 480), and >28 (n = 540). Predictive capability for long-term mortality was compared between angiographic scores and scores combining both angiographic and clinical variables.ResultsAt a mean follow-up of 4.4 years, mortality in the first, second, and third SS-II tertiles was 1.8%, 3.5%, and 9.4%, respectively (p < 0.0001). Multivariate analysis showed SS-II to be a strong independent predictor of mortality (hazard ratio: 1.76, 95% confidence interval: 1.10 to 2.82; p = 0.02) after LM-PCI. When compared with the angiographic SS, scores combining both clinical and angiographic variables, such as the SS-II, were superior in terms of long-term prognostication.ConclusionsResults of this large series of consecutive patients who underwent unprotected LM-PCI suggested that the SS-II has better long-term prognostic power in terms of mortality compared with the original purely angiographic SS. 相似文献