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41.
Expression profiling identifies the CRH/CRH-R1 system as a modulator of neurovascular gene activity.
Jan M Deussing Claudia Kühne Benno Pütz Markus Panhuysen Johannes Breu Mary P Stenzel-Poore Florian Holsboer Wolfgang Wurst 《Journal of cerebral blood flow and metabolism》2007,27(8):1476-1495
Corticotropin-releasing hormone receptor type 1 (CRH-R1)-deficient mice display reduced anxiety-like behavior, a chronic corticosterone deficit, and an impaired neuroendocrine stress response caused by disruption of the hypothalamic-pituitary-adrenocortical (HPA) axis. The molecular substrates and pathways of CRH/CRH-R1-dependent signaling mechanisms underlying the behavioral phenotype as well as the consequences of lifelong glucocorticoid deficit remain largely obscure. To dissect involved neuronal circuitries, we performed comparative expression profiling of brains of CRH-R1 mutant and wild-type mice using our custom made MPIP (Max Planck Institute of Psychiatry) 17k cDNA microarray. Microarray analysis yielded 107 genes showing altered expression levels when comparing CRH-R1 knockout mice with wild-type littermates. A significant proportion of differentially expressed genes was related to control of HPA and hypothalamic-pituitary-thyroid (HPT) axes reflecting not only the disturbance of the HPA axis in CRH-R1 mutant mice but also the interplay of both neuroendocrine systems. The spatial analysis of regulated genes revealed a prevalence for genes expressed in the cerebral microvasculature. This phenotype was confirmed by the successful cross-validation of regulated genes in CRH overexpressing mice. Analysis of the cerebral vasculature of CRH-R1 mutant and CRH overexpressing mice revealed alterations of functional rather than structural properties. A direct role of the CRH/CRH-R1 system was supported by demonstrating Crhr1 expression in the adult murine cerebral vasculature. In conclusion, these data suggest a novel, previously unknown role of the CRH/CRH-R1 system in modulating neurovascular gene expression and function. 相似文献
42.
Kathrin Scherer Wolfgang Studer Verena Figueiredo Andreas J Bircher 《Annals of allergy, asthma & immunology》2006,96(3):497-500
BACKGROUND: Blue dyes used for lymphatic mapping in sentinel lymph node biopsy cause intraoperative anaphylactic reactions in up to 2.7% of patients. With increasing implementation of this technique, the incidence of anaphylaxis to these dyes can be expected to increase. In the literature, the chemically often unrelated and inconsistently designated dyes have been confused, adding to other inconsistencies in the nomenclature. OBJECTIVE: To demonstrate the nomenclature, chemical and physiologic differences, and allergenicity of the various blue dyes used in a medical context. METHODS: We describe a patient with an intraoperative grade IV anaphylactic reaction to isosulfan blue. Immediate-type hypersensitivity was proved by positive skin test reactions and CD63 expression to isosulfan blue and cross-reactivity to patent blue V. RESULTS: A review of the literature clarified the exact nomenclature of the blue dyes and the possible pitfalls of confusing nomenclature in the context of structurally closely related dyes with different allergenic properties. For the detection of type I hypersensitivity, intracutaneous tests are valuable tools. An IgE-mediated mechanism has been shown recently. In most cases, sensitization exists without known previous exposure in a medical context. This may be due to the widespread use of such dyes in objects of everyday life. Preoperative antiallergic medication use does not prevent anaphylactic reactions but apparently reduces their severity. CONCLUSION: For better comparison and precision, the Chemical Abstracts Service number of the respective dye should always be given. 相似文献
43.
44.
Günther Sumann Dietmar Fries Andrea Griesmacher Gerda Falkensammer Anton Klingler Arnold Koller Werner Streif Sven Greie Beatrix Schobersberger Wolfgang Schobersberger 《Blood coagulation & fibrinolysis》2007,18(5):435-440
Prolonged physical exercise is associated with multiple changes in blood hemostasis. Eccentric muscle activation induces microtrauma of skeletal muscles, inducing an inflammatory response. Since there is a link between inflammation and coagulation we speculated that downhill running strongly activates the coagulation system. Thirteen volunteers participated in the Tyrolean Speed Marathon (42,195 m downhill race, 795 m vertical distance). Venous blood was collected 3 days (T1) and 3 h (T2) before the run, within 30 min after finishing (T3) and 1 day thereafter (T4). We measured the following key parameters: creatine kinase, myoglobin, thrombin-antithrombin complex, prothrombin fragment F1 + 2, D-dimer, plasmin-alpha(2)-antiplasmin complexes, tissue-type plasminogen activator antigen, plasminogen-activator-inhibitor-1 antigen and thrombelastography with ROTEM [intrinsic pathway (InTEM) clotting time, clot formation time, maximum clot firmness, alpha angle]. Thrombin generation was evaluated by the Thrombin Dynamic Test and the Technothrombin TGA test. Creatine kinase and myoglobin were elevated at T3 and further increased at T4. Thrombin-antithrombin complex, prothrombin fragment F1 + 2, D-dimer, plasmin-alpha(2)-antiplasmin complexes, tissue-type plasminogen activator antigen and plasminogen-activator-inhibitor-1 antigen were significantly increased at T3. ROTEM analysis exhibited a shortening of InTEM clotting time and clot formation time after the marathon, and an increase in InTEM maximum clot firmness and alpha angle. Changes in TGA were indicative for thrombin generation after the marathon. We demonstrated that a downhill marathon induces an activation of coagulation, as measured by specific parameters for coagulation, ROTEM and thrombin generation assays. These changes were paralleled by an activation of fibrinolysis indicating a preserved hemostatic balance. 相似文献
45.
46.
Immunological and echocardiographic evaluation of decellularized versus cryopreserved allografts during the Ross operation. 总被引:3,自引:0,他引:3
Francisco Diniz Affonso da Costa Pascal Maria Dohmen Daniele Duarte Cristina von Glenn Sérgio Veiga Lopes Hermínio Haggi Filho Marise Brenner Affonso da Costa Wolfgang Konertz 《European journal of cardio-thoracic surgery》2005,27(4):572-578
OBJECTIVE: Compare the immunological and echocardiographic data of decellularized versus cryopreserved allografts used for RVOT reconstruction during Ross operation. METHODS: From 16/01/03 thru 07/10/03, 20 Ross operations were performed using decellularized (n=11) or cryopreserved (n=9) allografts. Echocardiography was done at discharge, 1, 3, 6 and 12 months and annually thereafter. Samples for determination of antibodies against HLA class I and II were obtained preoperatively and at days 5, 10, 30, 90 and 180 postoperatively. These samples were tested by the ELISA method in LAT-M dishes (unspecific) for identification of circulating antibodies and the results expressed as mean sample values (Is=DO/cutoff). If positive, LAT-E (specific) was performed and PRA levels determined. RESULTS: There was no mortality. Cryopreserved allografts showed marked Is values elevations for class I and II antibodies which started at the first month and remained elevated up to 6 months. In contrast, of the patients receiving decellularized allografts, seven remained negative, two patients had only marginal elevation of class I antibodies and two patients showed abnormal elevations of PRA levels. This response happened earlier than in the cryopreserved group, starting on the 5th postoperative day and has returned to baseline levels in one case. Echocardiography showed mild, but significant, elevation of gradients in cryopreserved valves but none in the decellularized. CONCLUSIONS: Decellularized allografts had normal function up to 18 months and showed important reduction of the immunogenic response when compared to cryopreserved valves. 相似文献
47.
Christoph Testori c.m. Univ.-Prof. Dr. Hans Domanovits Univ.-Prof. Dr. Harald Herkner Univ.-Prof. Dr. Wolfgang Schreiber Univ.-Prof. Dr. Fritz Sterz Univ.-Prof. Dr. Anton N. Laggner 《Intensivmedizin und Notfallmedizin》2007,44(6):360-365
The elderly account for an ever-increasing proportion of emergency department patients. Demographic data show that the population which is 80 years of age or older will be further increasing in coming years. Due to this fact we sought the reasons of using of the emergency department by elderly patients (≥80 years), admitted by ambulance service, and to analyse the general management of this collective according to a younger comparison group. We used the data from a prospective registry, in which all consecutive patients admitted to the emergency department by ambulance service were included, to process this retrospective analysis. In this registry, diagnosis (in the ICD-10 classification), age, sex, and inpatient/outpatient treatment were documented. In addition further management, intensive care treatment, and outcome during emergency department stay were registered. The patients were stratified by age into two groups (< 80 years; ≥80 years). The observation period lasted from January 1, 2005 to December 31, 2005. During the study 6590 patients were observed of whom 5670 patients (86.0%) were under 80 years (PG<80) and 920 (14.0%) were 80 years of age or older (PG≥80). Comparing inpatient treatment (PG<80: 40.1%; PG≥80: 39.8%) vs outpatient treatment (PG<80: 59.9%; PG≥80: 60.2%) no significant difference between both groups was registered. In comparing the ICD- 10 main diagnosis categories, no relevant difference could be ascertained. By contrast a significantly higher mortality (3.0% vs 1.6%; p≤0.01) in the emergency department was shown within the PG≥80, especially if the diagnosis was myocardial infarction or stroke. The most frequent discharge diagnosis in the PG≥80 was acute myocardial infarction (6.7%). A percutaneous coronary intervention and artificial respiration was less frequently used in the elderly group. Patients beyond 80 years of age nowadays constitute a remarkable proportion of emergency department patients admitted by ambulance service. This group does not differ substantially from younger patients, neither in questions of inpatient or outpatient treatment nor in types of diagnosis. Elderly patients in the emergency department showed a higher mortality. Invasive interventions were less frequently used in this collective in comparison to younger patients. In consideration of the fact that the proportion of elderly will further increase in our population, this analysis may give basis for development of new strategies for the treatment of old patients in emergency departments. 相似文献
48.
Christoph R?cken Jutta Ernst Ernst Hund Hartmut Michels Jolanta Perz Wolfgang Saeger Orhan Sezer Simone Spuler Friedrich Willig und Hartmut H.-J. Schmidt 《Medizinische Klinik》2006,101(10):825-829
Ohne Zusammenfassung 相似文献
49.
Cardiac efficiency and oxygen consumption measured with 11C-acetate PET after long-term cardiac resynchronization therapy. 总被引:2,自引:0,他引:2
Oliver Lindner Jens S?rensen Jürgen Vogt Eva Fricke Detlev Baller Dieter Horstkotte Wolfgang Burchert 《Journal of nuclear medicine》2006,47(3):378-383
Cardiac resynchronization therapy (CRT) is a treatment option in patients with severe heart failure and left bundle-branch block (LBBB). This study evaluated the effects of 4 and 13 mo of CRT on myocardial oxygen consumption (MVO2) and cardiac efficiency as compared with mild heart failure patients without LBBB. METHODS: Sixteen patients with severe heart failure and LBBB due to idiopathic cardiomyopathy were studied at baseline and after 4 and after 13 mo of therapy. Thirteen patients with mild heart failure without LBBB served as a comparison group. The clearance rate (k2) of 11C-acetate was measured with PET to assess MVO2. Stroke volume was derived from the dynamic PET data according to the Stewart-Hamilton principle and, furthermore, cardiac efficiency using the work metabolic index. RESULTS: After 4 mo of CRT, stroke volume index (SVI) increased by 50% (P = 0.012) and cardiac efficiency increased by 41% (P < 0.001). Global k2 remained unchanged but regional k2 demonstrated a more homogeneous distribution pattern. The parameters showed no significant changes during therapy. Under CRT, cardiac efficiency, SVI, and the distribution pattern of regional k2 did not differ from mild heart failure patients without LBBB. CONCLUSION: CRT improves cardiac efficiency for at least 13 mo, as demonstrated by a higher SVI, whereas MVO2 remains unchanged. Cardiac efficiency, SVI, and the MVO2 distribution pattern reach the level of patients with mild heart failure without LBBB. The unfavorable hemodynamic performance in heart failure with LBBB is effectively restored by long-term CRT to the level of an earlier disease state. 相似文献
50.
Comparison of three different purification methods for the routine preparation of [11C] Metomidate. 总被引:1,自引:0,他引:1
Markus Mitterhauser Wolfgang Wadsak Oliver Langer Joern Schmaljohann Georg Zettinig Robert Dudczak Helmut Viernstein Kurt Kletter 《Applied radiation and isotopes》2003,59(2-3):125-128
PET with (R)-[O-methyl-11C] metomidate ([11C] MTO) is an attractive method for the characterisation of adrenal masses discriminating lesions of adrenal cortical origin from noncortical lesions. [11C] MTO was prepared by the reaction of [11C] methyliodide with the corresponding free acid. Three purification methods have been compared. The method of choice uses preparative HPLC with a ready-to-use weak acidic solvent. 相似文献