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961.
Effect of aqueous and alcoholic extract of C. anthelminticum was studied on the spontaneous movements of the whole worm and nerve-muscle preparation of S. cervi. Ethylacetate, acetone and methanol extract showed similar effect, of causing inhibition of spontaneous motility of the nerve-muscle preparation of S. cervi characterized by decreased amplitude and frequency of contractions. The inhibitory effect on the motility was reversible. Further, the extracts did not involve the blockade of cholinergic receptors as evidenced by the presence of unaltered stimulant response of acetylcholine in the presence of drug in bathing fluid.  相似文献   
962.
Drug resistant malaria was a major factor contributing to the failure of a worldwide campaign to eradicate malaria in the last century, and now threatens the large investment being made by the global community in the rollout of effective new drug combinations to replace failed drugs. Four related papers in this issue of Malaria Journal make the case for creating the World Antimalarial Resistance Network (WARN), which will consist of four linked open-access global databases containing clinical, in vitro, molecular and pharmacological data, and networks of reference laboratories that will support these databases and related surveillance activities. WARN will serve as a public resource to guide antimalarial drug treatment and prevention policies and to help confirm and characterize the new emergence of new resistance to antimalarial drugs and to contain its spread.  相似文献   
963.
964.
965.
Combinations therapy is often used in hypertensive patients whether combination therapy is necessary for preventing end‐organ damage is not known. The objective of this study was to determine in four different hypertensive animal models the necessity of adding the calcium channel blocker amlodipine to therapy with the ß‐blocker atenolol to modulate end‐organ damage. Spontaneously hypertensive rats, DOCA‐salt hypertensive rats, two‐kidney, one‐clip renovascular hypertensive rats and Lyon genetically hypertensive rats were used to study this objective. These animal models have different sensitivities to atenolol and amlodipine. The dosages of therapy employed were 10 mg/kg atenolol alone, 1 mg/kg amlodipine, 10 mg atenolol + 1 mg/kg amlodipine and 5 mg/kg atenolol+0.5 mg/kg amlodipine. BP was continuously recorded in all animals. After determination of baroreflex sensitivity, rats were sacrificed for end‐organ damage evaluation. The combination of amlodipine and atenolol had a synergistic inhibitory effect on blood pressure and blood pressure variability, and end‐organ damage as compared with monotherapy with atenolol or amlodipine in all animal models. Baroreflex sensitivity also improved with the combination therapy more than with monotherapy. In conclusion, atenolol and amlodipine combination exerts a superior effect on blood pressure, blood pressure variability, baroreflex sensitivity and end‐organ damage. The superior effect of the combination was observed in all four models of hypertension.  相似文献   
966.
Cadherins have been thought to facilitate the assembly of connexins (Cxs) into gap junctions (GJs) by enhancing cell-cell contact, however the molecular mechanisms involved in this process have remained unexplored. We examined the assembly of GJs composed of Cx43 in isogenic clones derived from immortalized and nontransformed rat liver epithelial cells that expressed either epithelial cadherin (E-Cad), which curbs the malignant behavior of tumor cells, or neuronal cadherin (N-Cad), which augments the invasive and motile behavior of tumor cells. We found that N-cad expression attenuated the assembly of Cx43 into GJs, whereas E-Cad expression facilitated the assembly. The expression of N-Cad inhibited GJ assembly by causing endocytosis of Cx43 via a nonclathrin-dependent pathway. Knock down of N-Cad by ShRNA restored GJ assembly. When both cadherins were simultaneously expressed in the same cell type, GJ assembly and disassembly occurred concurrently. Our findings demonstrate that E-Cad and N-Cad have opposite effects on the assembly of Cx43 into GJs in rat liver epithelial cells. These findings imply that GJ assembly and disassembly are the down-stream targets of the signaling initiated by E-Cad and N-Cad, respectively, and may provide one possible explanation for the disparate role played by these cadherins in regulating cell motility and invasion during tumor progression and invasion.  相似文献   
967.
A novel parvovirus, provisionally named Gorilla Bocavirus species 1 (GBoV1), was identified in four stool samples from Western gorillas (Gorilla gorilla) with acute enteritis. The complete genomic sequence of the new parvovirus revealed three open reading frames (ORFs) with an organization similar to that of known bocaviruses. Phylogenetic analysis using complete capsid and non structural (NS) gene sequence suggested that the new parvovirus is most closely related to human bocaviruses (HBoV). However, the NS ORF is more similar in length to the NS ORF found in canine minute virus and bovine parvovirus than in HBoV. Comparative genetic analysis using GBoV and HBoV genomes enabled characterization of unique splice donor and acceptor sites that appear to be highly conserved among all four HBoV species, and provided evidence for expression of two different NS proteins in all primate bocaviruses. GBoV is the first non-human primate bocavirus identified and provides new insights into the genetic diversity and evolution of this highly prevalent and recently discovered group of parvoviruses.  相似文献   
968.
Electrocardiogram (ECG) is an important bioelectrical signal used to asses the cardiac state of a patient. It consists of a recurrent wave sequence of P-wave, QRS-complex and T-wave associated with each beat. The QRS-complex is the prominent feature of the ECG. This paper presents a simple method using K-means clustering algorithm for the detection of QRS-complexes in ECG signal. Digital filters are used to remove the power line interference and baseline wander present in the ECG signal. K-means algorithm is used to classify QRS and non-QRS-region in the ECG signal. The performance of the algorithm is validated using dataset-3 of the CSE multi-lead measurement library. Detection rate of 98.66% is obtained. The percentage of false positive and false negative is 1.14% and 1.34% respectively. The mean and standard deviation of the errors between automatic and manual annotations is calculated to validate the delineation performance of the algorithm. The onsets and offsets of the detected QRS-complexes are found well within the tolerance limits as specified by the CSE library.  相似文献   
969.
TREM-1 is a superimmunoglobulin receptor present on neutrophils and monocytes, which plays an important role in the amplification of inflammation. The natural ligands for TREM-1 have not been identified; however, Toll-like receptor ligands are known to induce the expression of TREM-1. Blockade of TREM-1 has shown to improve survival in animal models of sepsis. In the present studies, we investigated the role of lipid mediators in the expression of TREM-1. In a macrophage cell line, we show that the expression of TREM-1 in response to LPS and bacteria Pseudomonas aeruginosa is inhibited by PGD2 and cyclopentanone prostaglandins PGJ2 and 15-dPGJ2. The inhibition of TREM-1 by these prostaglandins is independent of the PGD2 receptors and PPARγ but occurs by activation of Nrf2 and inhibition of NF-κB. Our data suggest a novel mechanism by which these prostaglandins exhibit anti-inflammatory effects and a new therapeutic approach to inhibition of TREM-1.  相似文献   
970.
Diabetes is a major risk factor for atherosclerosis. Atherogenesis involves endothelial dysfunction, activation and injury, inflammation, and smooth muscle cell migration and proliferation. Platelet activation in the narrowed arteries is the most proximate event in the culmination of an acute event such as acute myocardial infraction and stroke. Hyperglycemia is associated with all these adverse events in the process of genesis of atherosclerosis. The effect of diabetes (hyperglycemia) is mediated in large part by the state of enhanced oxidative stress, which is not counter-balanced by endogenous antioxidants. This paper reviews the ignition of oxidative stress in diabetes and the mediation of events leading to atherogenesis.  相似文献   
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