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991.
Hepatitis C virus (HCV) has chronically infected a large number of patients, leading to the development of steatosis, cirrhosis and, ultimately, hepatocellular carcinoma. The pathogenesis of HCV has not been fully explained, although steatosis is considered to contribute greatly to liver fibrosis progression, modulating host-cell lipid metabolism. Suspected underlying molecular mechanisms include interactions between HCV proteins and intracellular lipid metabolic pathways. Recent studies have suggested that the nucleocapsid of HCV (core) acts as a pathogenic factor involved in lipid droplet accumulation, changes in lipogenic gene expression and/or the activity of lipogenic proteins in a genotype-specific manner. In this review, we have tried to summarize the current knowledge regarding HCV-induced steatosis and the regulation of expression of host genes and receptors that aid in the viral life cycle and promote liver diseases.  相似文献   
992.
993.
The time delay between two surface electromyograms (EMGs) acquired along the conduction path is used to estimate mean action potential conduction velocity. Modeling the linear impulse response between “upstream” and “downstream” EMG signals permits an estimate of the distribution of velocities, providing more information. In this work, we analyzed EMG from bipolar electrodes placed on the tibialis anterior of 36 subjects, using an inter-electrode distance of 10 mm. Regularized least squares was used to fit the coefficients of a finite impulse response model. We trained the model on one recording, then tested on two others. The optimum correlation between the model-predicted and actual EMG averaged 0.70. We also compared estimation of the mean conduction delay from the peak time of the impulse response to the “gold standard” peak time of the cross-correlation between the upstream and downstream EMG signals. Optimal models differed from the gold standard by 0.02 ms, on average. Model performance was influenced by the regularization parameters. The impulse responses, however, incorrectly contained substantive power at very low time delays, causing delay distribution estimates to exhibit high probabilities at very short conduction delays. Unrealistic distribution estimates resulted. Larger inter-electrode spacing may be required to alleviate this limitation.  相似文献   
994.
ObjectiveThis study assessed the influence of chitosan nanoparticles on the fluoride-releasing ability of 4 glass ionomer cement (GIC) through an in vitro analysis.MethodsFour types of GIC (type II light cure universal restorative, type II universal restorative, GC Fuji VII, and type IX) were modified with nanochitosan particles; 10% chitosan was added to the glass ionomer liquid. Six specimens for each of the 4 groups were created, using expendable Teflon moulds. Discs of each type of GIC (n = 6) were immersed in deionised water at various time intervals. Electrodes selective for fluoride ions were employed to analyse the amount of released fluoride at 1, 7, 14, 21, and 28 days.ResultsChitosan-modified GICs showed greater fluoride release than conventional GICs at all time points. All samples showed an initial high release of fluoride that tapered off with time. The total amount of fluoride released increased from the 1st day to the 28th day on adding chitosan to all the 4 types of GIC. Amongst those, type IX high-strength posterior extra with chitosan released a considerably higher quantity of fluoride at all time intervals.ConclusionsIn all the experimental groups, adding chitosan to the glass ionomer liquid had an accelerating effect on its fluoride-releasing property.  相似文献   
995.
Background and aims. TRIF and MYD88 are intracellular adaptor proteins for TLR signaling, and altered expression of these molecules can lead to defective or unregulated immune responses. Furthermore, previous studies revealed that depression may alter immune responses, but its mechanisms of action are unclear yet. There is a possibility that immunity and depression are linked through molecules such as TRIF and MYD88, thus, the aim of this study was to evaluate the mRNA levels of TRIF and MYD88 in the PBMCs isolated from depressed medical students. Material and methods. The current study examined 38 depressed medical students studying in Iran and 43 healthy students from the same cohort as a control group. The mRNA levels of TRIF and MYD88 were examined in parallel with a housekeeping gene using real-time PCR. Results. Our results demonstrated that expression of TRIF and MYD88 were significantly elevated in PBMCs isolated from depressed patients when compared to healthy subjects. Conclusions. Based on the current results, it seems that chronic inflammation in depressed patients correlates to the over expression of TRIF and MYD88 genes. Our results show a possible link between the reported increases of chronic inflammation in depressed individuals with unbalanced expression of genes that regulate immunity.  相似文献   
996.
A bisensory method was developed for determining the psychometric functions and absolute thresholds for odor and sensory irritation of two odorous irritants. Individual and group thresholds for formaldehyde or pyridine were measured for 31 age-matched subjects (18?C35?years old). P 50 absolute thresholds were for formaldehyde odor 110?ppb (range 23?C505), for pyridine odor 77?ppb (range 20?C613), and for pyridine irritation 620?ppb (range 90?C3,656); too few subjects?? formaldehyde irritation thresholds were possible to determine (human exposures limited to 1?ppm). In spite of large interindividual differences, all thresholds for irritation were higher than for odor. The average slopes of the 62 psychometric functions for odor and the 32 possible for sensory irritation were highest for formaldehyde odor (83% per log ppb) and equal for pyridine odor and irritation (68% per log ppb). The bisensory method for measuring odor and sensory irritation jointly produced detection functions and absolute thresholds compatible with those earlier published; however, a steeper slope for sensory irritation than odor was expected for pyridine. The bisensory method is intended for measuring odor and sensory irritation to broadband mixtures and dynamic exposures, like indoor air.  相似文献   
997.
998.
A 24-year-old male patient with refractory Tourette syndrome was treated with deep brain stimulation (DBS) and developed subsequent bilateral subcortical haematomas. Additional blood tests revealed abnormalities of plasma factor XIIIA and tryptophan levels, which may be associated with Tourette syndrome. Neurosurgeons who perform DBS surgery on patients with Tourette syndrome must be aware of possible disastrous complications resulting from factor XIIIA disorders of blood haemostasis. Routine screening for this condition is not typically performed prior to surgery in these patients.  相似文献   
999.
In recent years, there has been tremendous growth in research on cerebellar motor and non-motor functions. Cerebellum is particularly involved in the spectrum of neurodevelopmental diseases. The 8th International Symposium of the Society for Research on the Cerebellum and Ataxia (SRCA) was held in Winnipeg, Manitoba, (Canada) on May 24–26, 2017. The main theme of the 8th International Symposium was “Development of the Cerebellum and Neurodevelopmental Disorders.” Advances in genetics, epigenetic, cerebellar neurogenesis, axonogenesis and gliogenesis, cerebellar developmental disorders including autism spectrum disorders (ASD), neuroimaging, cerebellar ataxias, medulloblastoma, and clinical investigation of cerebellar diseases were presented. The goal of this symposium was to provide a platform to discuss cutting-edge knowledge while allowing researchers and trainees the opportunity to share and discuss their front-line research and ideas with others in the field, make connections, and strengthen international collaborations. The Ferdinando Rossi lecture was delivered by Dr. Richard Hawkes on the topic of patterning of the cerebellar cortex. This symposium emphasized the major importance of the involvement of the cerebellum in neurodevelopmental diseases from the clinical, radiological, biological, and genetic standpoint.  相似文献   
1000.
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