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71.

Purpose  

Capsule endoscopy (CE) is a very useful tool for the evaluation of the small intestine, but it is time consuming. The aim of this study was to compare evaluation times and detection rates in two different reading modes (single view at a speed of 10 frames per second (fps) and four images simultaneously, i.e., quadview mode at a speed of 20 fps) to find the optimum setting mode for evaluation of CE videos.  相似文献   
72.
Liver fibrogenesis is associated with the transition of quiescent hepatocytes and hepatic stellate cells (HSCs) into the cell cycle. Exit from quiescence is controlled by E-type cyclins (cyclin E1 [CcnE1] and cyclin E2 [CcnE2]). Thus, the aim of the current study was to investigate the contribution of E-type cyclins for liver fibrosis in man and mice. Expression of CcnE1, but not of its homolog, CcnE2, was induced in fibrotic and cirrhotic livers from human patients with different etiologies and in murine wild-type (WT) livers after periodical administration of the profibrotic toxin, CCl(4) . To further evaluate the potential function of E-type cyclins for liver fibrogenesis, we repetitively treated constitutive CcnE1(-/-) and CcnE2(-/-) knock-out mice with CCl(4) to induce liver fibrosis. Interestingly, CcnE1(-/-) mice were protected against CCl(4) -mediated liver fibrogenesis, as evidenced by reduced collagen type I α1 expression and the lack of septum formation. In contrast, CcnE2(-/-) mice showed accelerated fibrogenesis after CCl(4) treatment. We isolated primary HSCs from WT, CcnE1(-/-) , and CcnE2(-/-) mice and analyzed their activation, proliferation, and survival in vitro. CcnE1 expression in WT HSCs was maximal when they started to proliferate, but decreased after the cells transdifferentiated into myofibroblasts. CcnE1(-/-) HSCs showed dramatically impaired survival, cell-cycle arrest, and strongly reduced expression of alpha smooth muscle actin, indicating deficient HSC activation. In contrast, CcnE2-deficient HSCs expressed an elevated level of CcnE1 and showed enhanced cell-cycle activity and proliferation, compared to WT cells. Conclusions: CcnE1 and CcnE2 have antagonistic roles in liver fibrosis. CcnE1 is indispensable for the activation, proliferation, and survival of HSCs and thus promotes the synthesis of extracellular matrix and liver fibrogenesis. (HEPATOLOGY 2012;56:1140-1149).  相似文献   
73.
In recent years, there has been an increasing interest in knowing the consequences of the patient-ventilator interaction in non-invasive mechanical ventilation. Therefore, several ventilator manufacturers have incorporated into their devices the possibility to monitor ventilation on-line and download the data stored in their internal memories. However, there is not a consensus as to how these data should be presented, and said devices have still not been sufficiently validated to be used systematically in clinical practice. The objective of the present study is to develop a critical, argumentative analysis of the technical characteristics for determining the monitor variables used in the different software programs incorporated in commercial ventilators. Likewise, the study contemplates the presentation of the measurements on the screen display, emphasizing the advantages and defects of each one and analyzing their behavior in common clinical practice situations, such as changes in the interface or the presence of accidental leaks. In addition, solution mechanisms are proposed for establishing future directives for the parameters that are important for clinicians, as well as the manner for providing and interpreting said information.  相似文献   
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In patients with epilepsy, not only seizures but also cognitive, emotional, and social functioning are of increasing interest in research (Kelley, Jacobs, &; Lowenstein, 2009 Kelley , M. S. , Jacobs , M. P. , &; Lowenstein , D. H. , for the NINDS Epilepsy Benchmark Stewards . ( 2009 ). The NINDS epilepsy research benchmarks . Epilepsia , 50 , 579582 . doi: doi:10.1111/j.1528-1167.2008.01813.x  [Google Scholar]). As a decrease in cognitive functions over the course of the illness is usually reported, we wanted to explore changes in Intelligence Scores observed after a neurofeedback treatment in patients with drug-resistant epilepsies. In a controlled study that compared the outcome of three different interventions (training to regulate slow cortical potentials, N = 34; training to regulate breath rate and the amount of carbon dioxide in the end tidal volume of the exhaled air, N = 11; modification of drug regime, N = 25), pre- and postmeasurements of a short version of the Wechsler Intelligence Scale were applied. The interval between the two assessments was more than 12 months, with a mean of 61 weeks. Mean age of the patients was 35, with a range from 17 to 57. The highly significant 7-point increment of IQ only after training of slow cortical potentials was not related to clinical (e.g., seizure reduction) or neuropsychological (e.g., attention and memory) variables. Instead, it was related to psychophysiological measures: IQ change was inversely related to the Latency of the P300 component of event-related brain potentials and directly related to the Latency of the P2 component and the increase of N2 Amplitude during training. We conclude that regulation training of slow cortical potentials improves IQ in patients with refractory partial epilepsy, which might be related to an improved ability for controlled allocation of cognitive resources.  相似文献   
76.
Defects in dystroglycan post-translational modification result in congenital muscular dystrophy with or without additional eye and brain involvement, are referred to as secondary dystroglycanopathies and have been associated with mutations in 11 different genes encoding glycosyltransferases or associated proteins. However, only one patient with a mutation in the dystroglycan encoding gene DAG1 itself has been described before. We here report a homozygous novel DAG1 missense mutation c.2006G>T predicted to result in the amino acid substitution p.Cys669Phe in the β-subunit of dystroglycan in two Libyan siblings. The affected girls presented with a severe muscle–eye–brain disease-like phenotype with distinct additional findings of macrocephaly and extended bilateral multicystic white matter disease, overlapping with the cerebral findings in patients with megalencephalic leucoencephalopathy with subcortical cysts. This novel clinical phenotype observed in our patients further expands the clinical spectrum of dystroglycanopathies and suggests a role of DAG1 not only for dystroglycanopathies but also for some forms of more extensive and multicystic leucodystrophy.  相似文献   
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Walker–Warburg syndrome (WWS) is a severe muscular dystrophy with eye and brain malformations. On a molecular level, WWS is a disorder of the O-linked glycosylation of α-dystroglycan and therefore referred to as one of the dystroglycanopathies. The disease family of muscular dystrophy–dystroglycanopathy (MDDG) contains a spectrum of severe to mild disorders, designated as MDDG type A to C. WWS, as the most severe manifestation, corresponds to MDDG type A. Defects in the genes POMT1, POMT2, POMGNT1, FKTN, FKRP, LARGE, GTDC2, G3GALNT2, GMPPB, B3GNT1, TMEM5 and COL4A1 and ISPD have been described as causal for several types of MDDG including WWS, but can only be confirmed in about 60–70% of the clinically diagnosed individuals. The proteins encoded by these genes are involved in the posttranslational modification of α-dystroglycan. Mutations in POMT1, POMT2, POMGNT1, FKTN, FKRP, LARGE, GMPPB, TMEM5 and COL4A1 and ISPD lead to a wide spectrum of phenotypes of congenital muscular dystrophies with or without eye and brain abnormalities. Patients with WWS frequently demonstrate a complete lack of psychomotor development, severe eye malformations, cobblestone lissencephaly and a hypoplastic cerebellum and brainstem, seizures, hydrocephalus and poor prognosis. Here, we present a boy with WWS who showed compound heterozygous changes in ISPD and discuss the clinical and radiological phenotype and the molecular genetic findings, including a novel pathogenic mutation in ISPD.  相似文献   
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