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41.
The faster the better: anastomosis time influences patient survival after deceased donor kidney transplantation
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Annemarie Weissenbacher Rupert Oberhuber Benno Cardini Sascha Weiss Hanno Ulmer Claudia Bösmüller Stefan Schneeberger Johann Pratschke Robert Öllinger 《Transplant international》2015,28(5):535-543
Despite a continuously growing knowledge of the impact of factors on kidney graft function, such as donor age, body mass index, and cold ischemia time, few data are available regarding anastomosis time (AT) and its impact on long‐term results. We investigated whether surgical AT correlates with patient and graft survival after kidney transplantation performing a retrospective analysis of 1245 consecutive deceased donor kidney transplantations between 01/2000 and 12/2010 at Innsbruck Medical University. Kaplan–Meier and log‐rank analyses were carried out for 1‐ and 5‐year patient and graft survival. AT was defined as time from anastomosis start until reperfusion. Median AT was 30 min. Five‐year survival of allografts with an AT >30 min was 76.6% compared with 80.6% in the group with AT <30 min (P = 0.027). Patient survival in the group with higher AT similarly was inferior with 85.7% after 5 years compared with 89.6% (P < 0.0001) [Correction added on February 18, 2015, after first online publication: the percentage value for patient survival was previously incorrect and have now been changed to 89.6%]. Cox regression analysis revealed AT as an independent significant factor for patient survival (HR 1.021 per minute; 95% CI 1.006–1.037; P = 0.006). As longer AT closely correlates with inferior long‐term patient survival, it has to be considered as a major risk factor for inferior long‐term results after deceased donor kidney transplantation. 相似文献
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The objective of this study was to introduce and evaluate a new methodology to quantify lower extremity movement symmetry using data from the stance phase in over-ground running. Seventeen subjects completed five heel–toe over-ground running trials per leg over a force platform at 3.33 ± 0.5 m s?1 with retro-reflective markers on both legs and the pelvis. Thirty kinetic and kinematic variables were collected and 12 were chosen as important variables for calculating symmetry based on low variance of the data and their functional relevance with respect to symmetry. The developed formula uses the integral of the absolute value of the difference between the left and right leg during the stance phase. The results were divided into a sagittal, transverse, and frontal index, as well as a global index for all three planes of motion. This enabled analyses from both general and categorical perspectives, whereby individuals could be identified as symmetrical in one plane and asymmetrical in the other. The new methodology allows for the evaluation of symmetry over the entire stance phase and accounts for time lags between left and right legs. To learn more about symmetry during particular movements, future research should include larger cohorts, use consecutive force platforms, examine the flight phase of running and include subjects that are known to have asymmetrical gait. 相似文献
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S. Magnitsky A. Roesch M. Herlyn J. D. Glickson 《Magnetic resonance in medicine》2011,66(5):1362-1373
Slowly cycling cells are believed to play a critical role in tumor progression and metastatic dissemination. The goal of this study was to develop a method for in vivo detection of slowly cycling cells. To distinguish these cells from more rapidly proliferating cells that constitute the vast majority of cells in tumors, we used the well‐known effect of label dilution due to division of cells with normal cycle and retention of contrast agent in slowly dividing cells. To detect slowly cycling cells, melanoma cells were labeled with iron oxide particles. After labeling, we observed dilution of contrast agent in parallel with cell proliferation in the vast majority of normally cycling cells. A small and distinct subpopulation of iron‐retaining cells was detected by flow cytometry after 20 days of in vitro proliferation. These iron‐retaining cells exhibited high expression of a biological marker of slowly cycling cells, JARID1B. After implantation of labeled cells as xenografts into immunocompromised mice, iron‐retaining cells were detected in vivo and ex vivo by magnetic resonance imaging that was confirmed by Prussian Blue staining. Magnetic resonance imaging detects not only iron retaining melanoma cells but also iron positive macrophages. Proposed method opens up opportunities to image subpopulation of melanoma cells, which is critical for continuous tumor growth. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc. 相似文献
46.
Johanning E Fischer S Christ E Göres B Landsbergis P 《AIHA journal : a journal for the science of occupational and environmental health and safety》2002,63(4):439-446
Whole-body vibration exposure of locomotive engineers and the vibration attenuation of seats in 22 U.S. locomotives (built between 1959 and 2000) was studied during normal revenue service and following international measurement guidelines. Triaxial vibration measurements (duration mean 155 min, range 84-383 min) on the seat and on the floor were compared. In addition to the basic vibration evaluation (aw rms), the vector sum (av), the maximum transient vibration value (MTVV/aw), the vibration dose value (VDV/(aw T1/4)), and the vibration seat effective transmissibility factor (SEAT) were calculated. The power spectral densities are also reported. The mean basic vibration level (aw rms) was for the fore-aft axis x = 0.18 m/sec2, the lateral axis y = 0.28 m/sec2, and the vertical axis z = 0.32 m/sec2. The mean vector sum was 0.59 m/sec2 (range 0.27 to 1.44). The crest factors were generally at or above 9 in the horizontal and vertical axis. The mean MTVV/aw was 5.3 (x), 5.1 (y), and 4.8 (z), and the VDV/(aw T1/4) values ranged from 1.32 to 2.3 (x-axis), 1.33 to 1.7 (y-axis), and 1.38 to 1.86 (z-axis), generally indicating high levels of shocks. The mean seat transmissibility factor (SEAT) was 1.4 (x) and 1.2 (y) and 1 (z), demonstrating a general ineffectiveness of any of the seat suspension systems. In conclusion, these data indicate that locomotive rides are characterized by relatively high shock content (acceleration peaks) of the vibration signal in all directions. Locomotive vertical and lateral vibrations are similar, which appears to be characteristic for rail vehicles compared with many road/off-road vehicles. Tested locomotive cab seats currently in use (new or old) appear inadequate to reduce potentially harmful vibration and shocks transmitted to the seated operator, and older seats particularly lack basic ergonomic features regarding adjustability and postural support. 相似文献
47.
A. Roesch M. Landthaler Priv.-Doz. Dr. T. Vogt 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》2003,54(9):871-885
Zusammenfassung Trotz Einsatz modernster molekularbiologischer Methoden konnte bis in die heutige Zeit, d. h. rund 20 Jahre nach Formulierung des sequenziellen Progressionsmodells melanozytärer Tumoren vom Nävus zum malignen Melanom, noch kein abschließender Konsens in der Diskussion gefunden werden, ob es sich beim dysplastischen Nävus um eine eigene Entität, eine Vorläuferläsion maligner Melanome oder eine Verlegenheitsdiagnose handelt. Zusätzlich erschwerend kommt hinzu, dass der Begriff "melanozytäre Dysplasie" auf allen Ebenen der dermatologischen Diagnostik (klinisches Erscheinungsbild, Dermatoskopie, Dermatohistopathologie, Molekularbiologie) unterschiedlichen Definitionen unterliegt. Die Frage, ob eine starre, arbiträre Unterteilung pigmentierter Hautveränderungen in einzelne Entitäten sinnvoll ist, bleibt unbeantwortet. Unabhängig jeglicher semantischer Verwirrung über den Begriff Dysplasie sollte der praktisch tätige Dermatologe in dem Bewusstsein handeln, dass jede klinisch oder dermatoskopisch verdächtige melanozytäre Läsion ein initiales malignes Melanom darstellen könnte und somit adäquat, d. h. durch Exzision, zu behandeln ist. Fundierte dermatologische Kenntnisse und der jeweilige Erfahrungsschatz des Untersuchers spielen nach wie vor die entscheidende Rolle.
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48.
Memory function during propofol and alfentanil anesthesia: predictive value of individual differences 总被引:11,自引:0,他引:11
BACKGROUND: Conscious recall and implicit memory have been shown to depend on hypnotic state as measured by electroencephalographic (EEG) bispectral index (BIS). A third expression of memory (unconscious-controlled memory) was recently observed after moderate to light sedation (BIS, 70-80). The present study investigated memory function during deep sedation (BIS, 60-70). As memory effects are small, the authors studied potential predictors of individual differences in memory performance. METHODS: Memory function and speed of information processing were assessed in 56 outpatients before surgery. During propofol anesthesia supplemented with alfentanil, patients heard a series of words while anesthesia was titrated to BIS, 60-70. In between words, response to command was assessed using the Isolated Forearm Technique. The authors tested memory with a word stem completion task and process dissociation procedure to distinguish explicit from implicit effects. RESULTS: Mean (+/- SD) BIS during word presentation was 64.0 +/- 3. Patients with conscious recall of verbal commands (n = 9) did not recall or recognize presented words. Even so, the process dissociation procedure revealed evidence of memory by a significantly higher hit rate in the inclusion condition (0.26) than in the exclusion condition (0.12). Patients without conscious recall showed no evidence of memory for presented words. Hit scores correlated significantly with scores in the preoperative memory test (r = 0.35). CONCLUSIONS: The authors found evidence of weak explicit memory function during anesthesia titrated to BIS, 60-70. The observations strongly suggest that postoperative memory relates to awareness during anesthesia, but the nature of this relation remains unclear. Memory seems more likely in patients with good preoperative memory performance. 相似文献
49.
The study compared patients' satisfaction with psychiatric inpatient treatment between an open and a closed ward. During a six-month period, all voluntarily participating patients on two wards of a psychiatric University hospital were investigated anonymously at admission and/or before discharge. A self-rating questionnaire (SATQ-98) was used to assess satisfaction with several domains of psychiatric inpatient treatment. In total, 135 questionnaires were received (retrieval rate 49%). The general level of satisfaction with treatment was high. General satisfaction, satisfaction with medication, ward equipment, visiting opportunities, and regulations for going out were significantly lower at discharge on the closed ward. Dissatisfaction with medication was related to low actual mood, and to low satisfaction with the frequency of psychotherapeutic interventions, visiting opportunities, and with the treating doctor. The results thus far strongly support the need for patients' satisfaction with treatment to be taken into account in order to improve psychiatric inpatient services, particularly on closed wards. 相似文献
50.
Nairz K Stocker H Schindelholz B Hafen E 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(16):10575-10580
With the availability of complete genome sequences, new rapid and reliable strategies for positional cloning become possible. Single-nucleotide polymorphisms (SNPs) permit the mapping of mutations at a resolution not amenable to classical genetics. Here we describe a SNP mapping procedure that relies on resolving polymorphisms by denaturing HPLC without the necessity of determining the nature of the SNPs. With the example of mapping mutations to the Drosophila nicastrin locus, we discuss the benefits of this method, evaluate the frequency of closely linked and potentially misleading second site mutations, and demonstrate the use of denaturing high-performance liquid chromatography to identify mutations in the candidate genes and to fine-map chromosomal breakpoints. Furthermore, we show that recombination events are not uniformly dispersed over the investigated region but rather occur at hot spots. 相似文献