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121.
Tobias Melcher Oliver Gruber 《Cortex; a journal devoted to the study of the nervous system and behavior》2009,45(2):189-685
In the current event-related functional magnetic resonance imaging (fMRI) study, we sought to trace back Stroop-interference to circumscribed properties of task-irrelevant word information - response-incompatibility, semantic incongruency and task-reference - that we conceive as conflict factors. Thereby, we particularly wanted to disentangle intermingled contributions of semantic conflict and response conflict to the overall Stroop-interference effect. To delineate neural substrates of single factors, we referred to the logics of cognitive subtraction and cognitive conjunction. Moreover, in a second step, we conducted correlation analyses to determine the relationship between neural activations and behavioral interference costs (i.e., conflict-related reaction time (RT) slowing) so as to further elucidate the functional role of the respective brain regions in conflict processing. Response-incompatibility was associated with activation in the left premotor cortex which can be interpreted as indicating motor competition or conflict, i.e., the presence of competing response tendencies. Accordingly, this activation was positively correlated with behavioral conflict costs. Semantic incongruency exhibited specific activation in the anterior cingulate cortex (ACC), the bilateral insula, and thalamus as well as in left somatosensory cortex. As supported by the consistent negative correlation with behavioral conflict costs, these activations most probably reflect strengthened control efforts to overcome interference and to ensure adequate task performance. Finally, task-reference elicited activation in the left temporo-polar cortex (TPC) and the right medial superior as well as in left rostroventral prefrontal cortex (rvPFC, sub-threshold activation). As strongly supported by prior studies' findings, this neural activation pattern may underlie residual semantic processing of the task-irrelevant word information. 相似文献
122.
E Rouah R Gruber W Shearer D Armstrong E P Hawkins 《American journal of clinical pathology》1988,89(4):543-546
Graft-versus-host disease (GVHD) classically involves the skin, intestines, liver, esophagus, and tongue. clinically apparent disease involving the heart, lungs, kidneys, and central nervous system (CNS) is frequently secondary to other complicating factors. This report describes a case of an infant with severe combined immune deficiency (SCID) who developed unusual manifestations of GVHD following a bone marrow transplant (BMT). These were complete heart block and respiratory insufficiency in the absence of significant pulmonary disease. He lived 133 days post-transplantation. At autopsy, the brain showed focal lymphohistiocytic aggregates which may represent a hitherto unreported lesion of GVHD. 相似文献
123.
Ohne ZusammenfassungHierzu Taf. IV. Fig. 1. 相似文献
124.
Ohne ZusammenfassungHierzu Taf. II. Fig. 3. 相似文献
125.
Ohne Zusammenfassung 相似文献
126.
Barry L. Gruber Lee D. Kaufman Mary J. Marchese William Roth Allen P. Kaplan 《Arthritis \u0026amp; Rheumatology》1988,31(8):1000-1006
IgG and IgM autoantibodies directed against IgE were determined in 95 serum samples from 67 patients with systemic lupus erythematosus, by an enzyme-linked immunosorbent assay. IgM anti-IgE autoantibodies were found in 18 patients (27%) and IgG anti-IgE autoantibodies were detected in 23 patients (34%). The specificity of the immunoassay was confirmed by the ability to inhibit binding with IgE myeloma, but not other immunoglobulin isotypes and the demonstration that the reactivity was directed to the Fc ε fragment of IgE. The IgG fraction of certain sera with anti-IgE activity was capable of inducing histamine release from control basophils and cutaneous mast cells. Clinical associations with the presence of anti-IgE activity were sought by retrospective chart analysis of 61 patients. Significant correlation was found with articular involvement, lymphadenopathy, and anti-DNA antibodies (P < 0.05). Anti-IgE autoantibodies are observed in a significant number of patients with systemic lupus erythematosus and may contribute to the pathogenesis of the vascular and articular lesions characteristic of this disease. 相似文献
127.
128.
STUDY DESIGN: Human anulus cells were cultured under control and experimental conditions to study associations between proliferation and clinical-demographic features of subjects from which cells were obtained. Statistical multiple regression analyses were applied to develop mathematic models relating proliferation to age, gender, Thompson score (denoting stage of disc degeneration), and status (control donor [postmortem]; surgical patient). OBJECTIVES: To identify the effect of donor characteristics on proliferative capacities of human disc cells. SUMMARY OF BACKGROUND DATA: As therapeutic options for disc degeneration increase, novel biologic options are important future considerations. Little is known about the influence of clinical-demographic features on cell proliferation. METHODS: Anulus cells were studied in two designs: 1) Cells from 12 individuals were grown in monolayer with 50 ng/mL interleukin growth factor-1 (IGF-I), 100 ng/mL insulin, or control conditions. 2) Cells from nine individuals were grown in three-dimensional culture with 10 ng/mL IGF-I or control conditions. Cell proliferation data and data on age, gender, Thompson score, and status were collected. Standard statistical analyses were used to develop correlation models. RESULTS: Data from monolayer experiments produced significant models fitting proliferation in the presence of low serum, 50 ng/mL IGF-I, or insulin, with age, gender, Thompson score, and status (respective R2: 0.827, 0.680, 0.850). Three-dimensional cultures exposed to 10 ng/mL IGF-I resulted in proliferation that correlated in a significant negative manner with Thompson score (r = -0.798). CONCLUSIONS: Clinical-demographic prognostic indicators may help predict levels of proliferation. Greater age, greater disc degeneration, female gender, and surgical derivation had deleterious effects on proliferation potential in this model. 相似文献
129.
Ansgar Gruber Till Weber Carolina Río Brtulos Sascha Vugrinec Peter G. Kroth 《Journal of basic microbiology》2009,49(1):58-72
Diatoms contribute a large proportion to the worldwide primary production and are particularly effective in fixing carbon dioxide. Possibly because diatom plastids originate from a secondary endocytobiosis, their cellular structure is more complex and metabolic pathways are rearranged within diatom cells compared to cells containing primary plastids. We annotated genes encoding isozymes of the reductive and oxidative pentose phosphate pathways in the genomes of the centric diatom Thalassiosira pseudonana and the pennate diatom Phaeodactylum tricornutum and bioinformatically inferred their intracellular distribution. Prediction results were confirmed by fusion of selected presequences to Green Fluorescent Protein and expression of these constructs in P. tricornutum. Calvin cycle enzymes for the carbon fixation and reduction of 3‐phosphoglycerate are present in single isoforms, while we found multiple isoenzymes involved in the regeneration of ribulose‐1,5‐bisphosphate. We only identified one cytosolic sedoheptulose‐1,7‐bisphosphatase in both investigated diatoms. The oxidative pentose phosphate pathway seems to be restricted to the cytosol in diatoms, since we did not find stromal glucose‐6‐phosphate dehydrogenase and 6‐phosphogluconolactone dehydrogenase isoforms. However, the two species apparently possess a plastidic phosphogluconolactonase. A 6‐phosphogluconolactone dehydrogenase is apparently plastid associated in P. tricornutum and might be active in the periplastidic compartment, suggesting that this compartment might be involved in metabolic processes in diatoms. Abbreviations: AL: aldolase, ATP: adenosine triphosphate, Chl: Chlorophyll, DIC: Normanski differential interference contrast, ER: endoplasmic reticulum, EST: expressed sequence tag, FBA: fructose‐1,6‐bisphosphate aldolase, FBPase: fructose‐1,6‐bisphosphatase, GAPDH: glycerinaldehyd‐3‐phosphate dehydrogenase, GFP: enhanced Green Fluorescent Protein, GPDH: glucose‐6‐phosphate dehydrogenase, GPI: glucose‐6‐phosphate isomerase, HMM: Hidden Markov Models, JGI: Joint Genome Institute, NADPH: nicotinamide adenine dinucleotide phosphate, NN: Neuronal networks, OPP: oxidative pentose phosphate pathway, PCR: Polymerase Chain Reaction, PGDH: 6‐phosphogluconolactone dehydrogenase, PGK: phosphoglycerate kinase, PGL: phosphogluconolactonase, Phatr2: version 2.0 of the Phaeodactylum tricornutum genome, PRK: phosphoribulokinase, RPE: ribulose‐phosphate epimerase, RPI: ribose‐5‐phosphate isomerase, RuBisCO: ribulose‐1,5‐bisphosphate carboxylase/oxygenase, SBPase: sedoheptulose‐1,7‐bisphosphatase, TAL: transaldolase, Thaps3: version 3.0 of the Thalassiosira pseudonana genome, TKL: transketolase, TPI: triosephosphate isomerase, UGGtransferase: UDP glucose‐starch glycosyl transferase. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
130.