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101.
Acute hepatitis C: high rate of both spontaneous and treatment-induced viral clearance 总被引:17,自引:0,他引:17
Gerlach JT Diepolder HM Zachoval R Gruener NH Jung MC Ulsenheimer A Schraut WW Schirren CA Waechtler M Backmund M Pape GR 《Gastroenterology》2003,125(1):80-88
BACKGROUND & AIMS: Acute hepatitis C virus infection accounts for approximately 20% of cases of acute hepatitis today. The aim of this study was to define the natural course of the disease and to contribute to the development of treatment strategies for acute hepatitis C virus. METHODS: The diagnosis of acute hepatitis C virus in 60 patients was based on seroconversion to anti-hepatitis C virus antibodies or clinical and biochemical criteria and on the presence of hepatitis C virus RNA in the first serum sample. RESULTS: Fifty-one of 60 (85%) patients presented with symptomatic acute hepatitis C virus. In the natural (untreated) course of acute symptomatic hepatitis C (n = 46), spontaneous clearance was observed in 24 patients (52%), usually within 12 weeks after the onset of symptoms, whereas all asymptomatic patients (n = 9) developed chronic hepatitis C. The start of antiviral therapy (interferon-alpha with or without ribavirin) beyond 3 months after the onset of acute hepatitis induced sustained viral clearance in 80% of treated patients. CONCLUSIONS: The management of acute hepatitis C has to take into account the high rate of spontaneous viral clearance within 12 weeks after the onset of symptomatic disease. Treatment of only those patients who remain hepatitis C virus RNA positive for more than 3 months after the onset of disease led to an overall viral clearance (self-limited and treatment induced) in 91% of patients, and unnecessary treatment was avoided in those with spontaneous viral clearance. Patients with asymptomatic acute hepatitis C virus infection are unlikely to clear the infection spontaneously and should be treated as early as possible. 相似文献
102.
103.
Tilman J. Alpermann Jörg Plieske Ahmad O. Mal Ofer Gon Michael L. Berumen 《Conservation Genetics Resources》2014,6(4):1031-1034
The cardinalfish Siphamia tubifer has been selected as a model for the study of genetic connectivity in reef-associated fishes among marine-protected-areas in Socotra Island in the northwestern Indian Ocean (part of the Socotra Archipelago, a UNESCO World Heritage Site since 2008). Twenty-six novel microsatellite markers are described for S. tubifer and are now available for studies on its genetic population structure. In a population sample from Socotra Island, the newly developed markers possessed between three and 20 alleles. Expected and observed heterozygosity ranged from 0.56–0.96 to 0.55–0.95, respectively. The markers did not show deviations from Hardy–Weinberg equilibrium and were not in linkage disequilibrium. 相似文献
104.
Ioannis Kyvernitakis Tilman D. Rachner Anja Urbschat Olaf Hars Lorenz C. Hofbauer Peyman Hadji 《Journal of cancer research and clinical oncology》2014,140(10):1671-1680
Purpose
While their negative impact on bone health is well established, the effects of aromatase inhibition (AI) on Wnt inhibitors and osteoprotegerin (OPG) are unknown. The aim of the study was to investigate the effects of AI on serum levels of sclerostin, DKK-1 and OPG, as well as their associations with PINP and CTX as markers of bone turnover and bone mineral density (BMD) assessed by DXA.Methods
We conducted a prospective longitudinal analysis of 70 postmenopausal women with hormone receptor-positive early breast cancer (BC) treated with anastrozole. All measurements were performed at baseline, 12 and 24 months of treatment. We measured the association of the investigated variables with circulating bone turnover markers, as well as with the BMD.Results
After 24 months of AI therapy, sclerostin and OPG concentrations increased from 29.5 pmol/l (SD = 15.1) and 6.8 pmol/l (SD = 2.2) at baseline to 43.2 pmol/l (SD = 20.6) (p < 0.001) and 7.4 pmol/l (SD = 2.2) (p = 0.028), respectively. DKK-1 levels decreased from 34.3 pmol/l (SD = 13.5) at baseline to 29.7 pmol/l (SD = 12.3) at the 24-month visit (p = 0.005). Sclerostin levels significantly correlated with PTH, OPG and BMD of the lumbar spine, while DKK-1 correlated with the BMD of the femoral neck and of the total hip.Conclusions
The observed increase in sclerostin levels indicates a central role of osteocytes in bone turnover in women with BC. 相似文献105.
106.
Martin M.N. Schmitt Line Fraemohs Tilman M. Hackeng Christian Weber Rory R. Koenen 《Atherosclerosis》2014
Background
Junctional adhesion molecule (JAM-) A is a transmembrane protein expressed in many cell types and maintains junctional integrity in endothelial cells. Upon inflammatory stimulation, JAM-A relocates to the apical surface and might thereby facilitate the recruitment of leukocytes.Objective
Although inflammatory JAM-A redistribution is an established process, further effort is required to understand its exact role in the transmigration of mononuclear cells, particularly under atherogenic conditions.Methods
By the use of RNA interference and genetic deletion, the role of JAM-A in the transmigration of T cells and monocytes through aortic endothelial cells was investigated. JAM-A–localization and subsequent mononuclear cell rolling, adhesion and transmigration were explored during endothelial inflammation, induced by oxidized LDL or cytokines.Results
RNA interference or genetic deletion of JAM-A in aortic endothelial cells resulted in a decreased transmigration of mononuclear cells. Treatment of the endothelial cells with oxLDL resulted in an increase of both permeability and apical JAM-A presentation, as shown by bead adhesion and confocal microscopy experiments. Redistribution of JAM-A resulted in an increased leukocyte adhesion and transmigration, which could be inhibited with antibodies against JAM-A or by lovastatin-treatment, but not with the peroxisome proliferator activated receptor gamma-agonist pioglitazone.Conclusions
This study demonstrates that redistribution of JAM-A in endothelial cells after stimulation with pro-atherogenic oxidized lipoproteins results in increased transmigration of mononuclear cells. This inflammatory dispersal of JAM-A could be counteracted with statins, revealing a novel aspect of their mechanism of action. 相似文献107.
Alfonso Martín‐Peña Angel Acebes José‐Rodrigo Rodríguez Valerie Chevalier Sergio Casas‐Tinto Tilman Triphan Roland Strauss Alberto Ferrús 《The European journal of neuroscience》2014,39(10):1586-1601
Cellular ultrastructures for signal integration are unknown in any nervous system. The ellipsoid body (EB) of the Drosophila brain is thought to control locomotion upon integration of various modalities of sensory signals with the animal internal status. However, the expected excitatory and inhibitory input convergence that virtually all brain centres exhibit is not yet described in the EB. Based on the EB expression domains of genetic constructs from the choline acetyl transferase (Cha), glutamic acid decarboxylase (GAD) and tyrosine hydroxylase (TH) genes, we identified a new set of neurons with the characteristic ring‐shaped morphology (R neurons) which are presumably cholinergic, in addition to the existing GABA‐expressing neurons. The R1 morphological subtype is represented in the Cha‐ and TH‐expressing classes. In addition, using transmission electron microscopy, we identified a novel type of synapse in the EB, which exhibits the precise array of two independent active zones over the same postsynaptic dendritic domain, that we named ‘agora’. This array is compatible with a coincidence detector role, and represents ~8% of all EB synapses in Drosophila. Presumably excitatory R neurons contribute to coincident synapses. Functional silencing of EB neurons by driving genetically tetanus toxin expression either reduces walking speed or alters movement orientation depending on the targeted R neuron subset, thus revealing functional specialisations in the EB for locomotion control. 相似文献
108.
Markus Jäger Prisca Weiser Thomas Becker Karel Frasch Gerhard Längle Daniela Croissant Tilman Steinert Susanne Jaeger Reinhold Kilian 《Psychiatry research》2014
Course trajectory analyses have been performed primarily for treatment response in acute episodes of schizophrenic disorders. As yet, corresponding data for the long-term course are lacking. Within a multicenter prospective observational study, 268 patients with schizophrenia were assessed at discharge from hospital and followed up after 6, 12, 18, and 24 months. A latent class growth analysis was performed on the scores from the Positive and Negative Syndrome Scale (PANSS). A two-class conditional latent class model showed the best data fit (Entropy: 0.924). The model divided the sample into a group with amelioration in all PANSS subscales (60%) and a group with stable positive/negative and deteriorating general psychopathology symptoms (40%). Global functioning (GAF score), gender, age, living situation and involuntary admission predicted course trajectory class membership. The model was predictive of significant differences between the two groups in health care service costs and quality of life. The results underline the heterogeneous course of the illness, which ranged from amelioration to deterioration over a 2-year period. Statistical models such as trajectory analysis could help to identify more homogenous subtypes in schizophrenia. 相似文献
109.
110.
Fellype C. Barreto Rodrigo B. de Oliveira Joyce Benchitrit Loïc Louvet Raja Rezg Sabrina Poirot Vanda Jorgetti Tilman B. Drüeke Bruce L. Riser Ziad A. Massy 《Journal of bone and mineral metabolism》2014,32(6):636-644
Vascular calcification (VC) is a risk factor for cardiovascular mortality in the setting of chronic kidney disease (CKD). Pyrophosphate (PPi), an endogenous molecule that inhibits hydroxyapatite crystal formation, has been shown to prevent the development of VC in animal models of CKD. However, the possibility of harmful effects of exogenous administration of PPi on bone requires further investigation. To this end, we examined by histomorphometry the bone of CKD mice after intraperitoneal PPi administration. After CKD creation or sham surgery, 10-week-old female apolipoprotein-E knockout (apoE?/?) mice were randomized to one non-CKD group or 4 CKD groups (n = 10–35/group) treated with placebo or three distinct doses of PPi, and fed with standard diet. Eight weeks later, the animals were killed. Serum and femurs were sampled. Femurs were processed for bone histomorphometry. Placebo-treated CKD mice had significantly higher values of osteoid volume, osteoid surface and bone formation rate than sham-placebo mice with normal renal function. Slightly higher osteoid values were observed in CKD mice in response to very low PPi dose (OV/BV, O.Th and ObS/BS) and, for one parameter measured, to high PPi dose (O.Th), compared to placebo-treated CKD mice. Treatment with PPi did not modify any other structural parameters. Mineral apposition rates, and other parameters of bone formation and resorption were not significantly different among the treated animal groups or control CKD placebo group. In conclusion, PPi does not appear to be deleterious to bone tissue in apoE?/? mice with CKD, although a possible stimulatory PPi effect on osteoid formation may be worth further investigation. 相似文献