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61.
Reproducibility of tissue Doppler parameters of asynchrony in patients with advanced LV dysfunction.
Eva Mandysová Tomás Mráz Milos Táborsky Petr Niederle 《European journal of echocardiography》2008,9(4):509-515
AIMS: To assess the reproducibility of tissue Doppler myocardial velocities in patients with dilated ventricles and markedly reduced systolic function (ejection fraction <35%). METHODS AND RESULTS: Forty-one patients referred for cardiac resynchronization therapy (CRT) were evaluated using tissue Doppler echocardiography. The inter and intra-individual reproducibility of peak systolic myocardial velocities and the intra-ventricular delay in three apical projections was assessed by repeated evaluation of each registered data set. Variability (measured by the coefficient of variation) ranged between 18 and 56% for the peak systolic velocities and between 32 and 117% for the time intervals. CONCLUSION: The reproducibility of the tissue Doppler echocardiography parameters (peak systolic myocardial velocity and intra-ventricular delay) was poor in our set of patients with dilated left ventricles and low ejection fraction. The most probable causes of our poor results are discussed including the missing standardization of the TDI measurements. 相似文献
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Lukasova Vera Buzgo Matej Vocetkova Karolina Kubíkov Tereza Tonar Zbynk Doupnik Miroslav Blahnova Veronika Litvinec Andrej Sovkova Vera Voltrov Barbora Staffa Andrea Svora Petr Kralickova Milena Amler Evzen Filova Eva Rustichelli Franco Rampichova Michala 《RSC advances》2018,8(39):21889
Bone regeneration is a long-term process requiring proper scaffolding and drug delivery systems. The current study delivers a three-dimensional (3D) scaffold prepared by blend centrifugal spinning loaded with the osteogenic supplements (OS) β-glycerol phosphate, ascorbate-2-phosphate and dexamethasone. The OS were successfully encapsulated into a fibrous scaffold and showed sustained release for 30 days. Furthermore, biological testing showed the osteoinductive properties of the scaffolds on a model of human mesenchymal stem cells and stimulatory effect on a model of osteoblasts. The osteoinductive properties were further proved in vivo in critical size defects of rabbits. The amount of bone trabecules was bigger compared to control fibers without OS. The results indicate that due to its long-term drug releasing properties, single step fabrication process and 3D structure, the system shows ideal properties for use as a cell-free bone implant in tissue-engineering.Bone regeneration is a long-term process requiring proper scaffolding and drug delivery systems. 相似文献
64.
Epicardial RFA to Achieve Electrical PV Isolation. During catheter ablation of atrial fibrillation, ablation within the pulmonary veins is undesirable due to the risk of pulmonary venous stenosis and the possibility of leaving residual cuffs of arrhythmogenic tissue proximal to the ablation lesion set. An extra-ostial pulmonary vein isolation strategy may circumvent these limitations, but achieving electrical isolation can be technically challenging, even with the use of saline-irrigated radiofrequency energy technology. This report describes the successful use of epicardial radiofrequency ablation in a patient in whom endocardial irrigated radiofrequency ablation failed to achieve extra-ostial pulmonary vein isolation. 相似文献
65.
Stanislava Eisová Ondřej Naňka Petr Velemínský Emiliano Bruner 《Journal of anatomy》2021,239(5):1050-1065
Middle meningeal vessels, dural venous sinuses, and emissary veins leave imprints and canals in the endocranium, and thus provide evidence of vascular patterns in osteological samples. This paper investigates whether craniovascular morphology undergoes changes in craniosynostotic human skulls, and if specific alterations may reflect structural and functional relationships in the cranium. The analyzed osteological sample consists of adult individuals with craniosynostoses generally associated with dolichocephalic or brachycephalic proportions, and a control sample of anatomically normal adult skulls. The pattern and dominance of the middle meningeal artery, the morphology of the confluence of the sinuses, and the size and number of the emissary foramina were evaluated. Craniovascular morphology was more diverse in craniosynostotic skulls than in anatomically normal skulls. The craniosynostotic skulls often displayed enlarged occipito-marginal sinuses and more numerous emissary foramina. The craniosynostotic skulls associated with more brachycephalic morphology often presented enlarged emissary foramina, while the craniosynostotic skulls associated with dolichocephalic effects frequently displayed more developed posterior branches of the middle meningeal artery. The course and morphology of the middle meningeal vessels, dural venous sinuses, and emissary veins in craniosynostotic skulls can be related to the redistribution of growth forces, higher intracranial pressure, venous hypertension, or thermal constraints. These functional and structural changes are of interest in both anthropology and medicine, involving epigenetic traits that concern the functional and ontogenetic balance between soft and hard tissues. 相似文献
66.
Jitka Majovska Igor Nestrasil Amy Paulson David Nascene Katarina Jurickova Anna Hlavata Troy Lund Paul J. Orchard Manuela Vaneckova Jiri Zeman Martin Magner Petr Dusek 《Molecular genetics and metabolism》2021,132(3):189-197
ObjectiveDespite profound neurological symptomatology there are only few MRI studies focused on the brain abnormalities in alpha-mannosidosis (AM). Our aim was to characterize brain MRI findings in a large cohort of AM patients along with clinical manifestations.MethodsTwenty-two brain MRIs acquired in 13 untreated AM patients (8 M/5F; median age 17 years) were independently assessed by three experienced readers and compared to 16 controls.ResultsFocal and/or diffuse hyperintense signals in the cerebral white matter were present in most (85%) patients. Cerebellar atrophy was common (62%), present from the age of 5 years. Progression was observed in two out of 6 patients with follow-up scans. Cortical atrophy (62%) and corpus callosum thinning (23%) were already present in a 13-month-old child. The presence of low T2 signal intensity in basal ganglia and thalami was excluded by the normalized signal intensity profiling. The enlargement of perivascular spaces in white matter (38%), widening of perioptic CSF spaces (62%), and enlargement of cisterna magna (85%) were also observed. Diploic space thickening (100%), mucosal thickening (69%) and sinus hypoplasia (54%) were the most frequent non-CNS abnormalities.ConclusionWhite matter changes and cerebellar atrophy are proposed to be the characteristic brain MRI features of AM. The previously reported decreased T2 signal intensity in basal ganglia and thalami was not detected in this quantitative study. Rather, this relative MR appearance seems to be related to the diffuse high T2 signal in the adjacent white matter and not the gray matter iron deposition that has been hypothesized. 相似文献
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Partha Sen Romana Gerychova Petr Janku Marta Jezova Iveta Valaskova Colby Navarro Iris Silva Claire Langston Stephen Welty John Belmont Pawel Stankiewicz 《European journal of human genetics : EJHG》2013,21(4):474-477
Alveolar capillary dysplasia with misalignment of pulmonary veins (ACD/MPV) is a rare developmental lung disorder that is uniformly lethal. Affected infants die within the first few weeks of their life despite aggressive treatment, although a few cases of late manifestation and longer survival have been reported. We have shown previously that mutations and deletions in FOXF1 are a cause of this disorder. Although most of the cases of ACD/MPV are sporadic, there have been infrequent reports of familial cases. We present a family with five out of six children affected with ACD/MPV. DNA analysis identified a missense mutation (c.416G>T; p.Arg139Leu) in the FOXF1 gene that segregated in the three affected siblings tested. The same variant is also present as a de novo mutation in the mother and arose on her paternally derived chromosome 16. The two tested affected siblings share the same chromosome 16 haplotype inherited from their maternal grandfather. Their single healthy sibling has a different chromosome 16 haplotype inherited from the maternal grandmother. The results are consistent with paternal imprinting of FOXF1 in human. 相似文献
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