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61.
C. von Schnakenburg P. F. Hoyer K. Latta H. J. Schlitt Gisela Offner 《Monatsschrift für Kinderheilkunde》1997,145(2):114-116
Zusammenfassung
Wir berichten über ein 7 Jahre altes M?dchen, das 14 Tage nach einer Nierentransplantation an Varizellen erkrankte. Erste
Symptome waren krampfartige Bauchschmerzen mit radiologischen Hinweisen auf einen Obturationssubileus bei Obstipation. Als
nach abführenden Ma?nahmen keine Besserung auftrat, wurde eine Probelaparotomie mit Entfernung des Tenckhoff-Dialysekatheters
durchgeführt. Dabei zeigte sich kein pathologischer Befund, insbesondere fanden sich keine Briden. Zwei Tage nach Beginn der
abdominalen Symptomatik trat ein zun?chst uncharakteristisches Exanthem auf. Aus den sich in den n?chsten 12 h entwickelnden
Bl?schen konnte Varicella-Zoster-Virus isoliert werden. Trotz hochdosierter Gabe von Aciclovir und Varicella-Zoster-Immunglobulin
entwickelte sich ein fulminantes Leberversagen mit Verbrauchskoagulopathie. Die Patientin verstarb am 18. postoperativen Tag
trotz intensiver supportiver Therapie im Multiorganversagen.
Diskussion: Vor dem Hintergrund dieser letalen Varizelleninfektion wird auf die Komplikationen und die teilweise untypischen
Verl?ufe von Windpocken bei immunsupprimierten Kindern hingewiesen. Eine aktive Impfung ist daher bei seronegativen Patienten
vor einer geplanten Organtransplantation zu fordern.
相似文献
62.
Zusammenfassung. Die Klonierung, Sequenzierung und Produktion von hochreinen Allergenen bietet die Möglichkeit, perfekt standardisierte Allergenpräparate herzustellen. Die Entwicklung eines neuen Klonierungssystems, das auf filamentösen Phagen basiert, führte zu einer schnellen Isolierung und Charakterisierung von Aspergillus fumigatus-Allergenen. Die auf diesem Weg rekombinant hergestellten Proteine wurden serologisch und klinisch geprüft und ihr routinemä-ßiger Einsatz im ImmunoCAP-System evaluiert. Es gelang eine quantitative Übereinstimmung zwischen Hauttestergebnissen und Serologie nachzuweisen, welche das Potential rekombinanter Allergene in der Diagnostik allergischer Krankheiten aufzeigt. Darüber hinaus trägt die Charakterisierung der Pilzallergene wesentlich zum Verständnis der moiekularen Natur der allergieauslösenden Komponenten bei Zum jetzigen Zeitpunkt können, abgesehen von Proteinen mit unbekannten biologischen Funktionen, die Pilzallergene in zwei Klassen eingeteilt werden: 1. Spezies-spezifische sezcrnierte Allergene und 2. cytoplasmatische, hoch konservierte Proteine. Diese letztgenannten Pilzallergene zeigen auch zu Proteinen aus phylogenetisch weit entfernten Organismen weitreichende Sequenzhomologien. Neben der daraus zu erwartenden IgE-Kreuzreaktivität findet man in einigen Fällen auch eine Kreuzreaktivität mit den homologen humanen Proteinen, was auf Autoimmunreaktionen, bei Pilzalleigien hindeutet. Summary. Cloning, sequencing and production of highly pure recombinant allergens allows to produce perfectly standardised allergen preparations. The development of a new cloning system based on filamentous phage allowed the fast isolation and characterisation of allergens from the fungus Aspergillus fumigatus. The produced recombinant allergens were tested in serological and clinical studies as well as for their performance for routine assessments in the ImmunoCAP-system. Thereby, a perfect correlation between skin test results and serology was found showing the potential of recombinant allergens for the diagnosis of allergic diseases. Moreover, the characterisation of fungal allergens substantially contributes to our understanding of the molecular nature of proteins involved in the elication of allergic reactions. Apart from allergenic proteins with unknown biological function, fungal allergens can be subdivided into two classes: 1. Species-specific, secreted proteins and 2. cytoplasmic, even in phylogenetically distant organisms, well conserved proteins. These fungal allergens show extended sequence similarity, a high level of IgE cross-reactivity and in some cases also cross-reactivity with homologous human proteins indicating autoimmune reactions involved in fungal allergy. 相似文献
63.
64.
Human cornea construct HCC-an alternative for in vitro permeation studies? A comparison with human donor corneas. 总被引:1,自引:0,他引:1
Stephan Reichl Stefanie D?hring Jürgen Bednarz Christel C Müller-Goymann 《European journal of pharmaceutics and biopharmaceutics》2005,60(2):305-308
Transcorneal in vitro permeation studies of ophthalmic drugs are normally performed with either excised animal corneas or latterly corneal cell culture models. A good correlation between these models and excised animal corneas regarding permeation behaviour of drugs has already been shown. However, comparisons between corneal in vitro models containing human cells and excised human corneas do not exist yet. Therefore in the present study the transcorneal permeation of six different model drugs (pilocarpine hydrochloride, befunolol hydrochloride, hydrocortisone, diclofenac sodium, clindamycin hydrochloride and timolol maleate) across our previously described three-dimensional organotypic human cornea construct (HCC) was tested using Franz diffusion cells and compared with permeation data obtained from human donor corneas. The HCC showed a similar permeation behaviour compared with human donor cornea for all substances. The permeabilities (permeation coefficients P) of the human cornea equivalent versus the human donor cornea were the same in the case of diclofenac, clindamycin, timolol, but marginally decreased for hydrocortisone and slightly increased for pilocarpine and befunolol. These small differences of permeation coefficients were expressed as factors and only varied from 0.8 to 1.4. The results indicate that the HCC may be an alternative for in vitro permeation studies and appropriate for predicting drug absorption into the human eye. 相似文献
65.
Mudra Kohli Kumar Courtney Judd James D. Hoyer Kenneth C. Swanson Linda Nelson Jennifer L. Oliveira 《Hemoglobin》2014,38(3):211-212
The increasing availability of DNA sequencing of globin genes has improved our ability to detect conditions that were presumed to be extremely rare. These conditions may remain undiagnosed due to unfamiliarity with clinical presentation, relative unavailability of advanced diagnostic alternatives, or may defy detection by being electrophoretically silent or extreme instability rendering their presence to be below detection level. Genetic studies were pursued in a mother and daughter with severe hemolytic anemia as initial testing failed to be diagnostic. DNA sequence analysis of the β-globin gene identified Hb Manukau [β67(E11)Val?→?Gly; HBB: c.203T?>?G], an extremely unstable hemoglobin (Hb) variant. This is the second family described with this condition (first in the western hemisphere). An astute clinician may benefit from being persistent and pursuing additional testing including molecular genetic characterization where clinical suspicion remains high. 相似文献
66.
67.
Johannes Hohenberger Anton Friesen Stefanie Wieck Klaus Kümmerer 《Sustainable Chemistry and Pharmacy》2022
The field of chemical rodent control has seen no major developments in the last decades, even though anticoagulant rodenticides (AR), the mainly used substances to manage mice and rats, are known environmental pollutants and candidates for substitution under the European Biocidal Products Regulation 528/2012. Moreover, recent political developments in Europe and the USA demand more safety and sustainability in the management of chemicals, reinforcing the need for environmentally friendly substances. In this concept study, we present a step-by-step approach to improve the environmental properties of rodenticides. Repurposing of existing pharmaceuticals, the use of enantiomerically pure rodenticides, or the improvement of the formulation by microencapsulation can help to alleviate environmental problems caused by AR in the short term. Modification of the chemical structures or the development of prodrugs as medium-term strategies can further improve environmental properties of existing compounds. Ultimately, the development of new substances from scratch enables the utilisation of so far ignored modes of actions and the application of modern safe and sustainable-by-design principles to improve target specificity and reduce the negative impact on non-target organisms and the environment. Overall, our concept study illustrates the great potential for improvement in the field of chemical rodent control when applying available techniques of green and sustainable chemistry to known or potential rodenticides. Most promising in the medium term is microencapsulation that would allow for the use of acutely acting substances as it could circumvent bait shyness. On a longer timescale the de novo design of new rodenticides, which is the only method that can combine a high target specificity with good environmental properties, is the most promising approach. 相似文献
68.
Background: Depression is a common disease, yet it is not commonly studied in the Emergency Medicine literature. Study Objectives: To evaluate the prevalence of emergency department (ED) patients who have the symptoms of depression. Design: This was a prospective observational study performed at two EDs over a 9-month period. Adult patients were screened for depression symptoms by Diagnostic and Statistical Manual of Mental Disorders, 4th edition criteria. Results: There were 505 patients screened from April through December, 2004. Of the 505 patients, 109 (21.6%) screened positive for the symptoms of depression. The prevalence of positive screens was similar at each ED. Conclusion: About 1 in 5 ED patients may be suffering with depression. 相似文献
69.
70.
Stefanie Enriquez‐Geppert Tom Eichele Karsten Specht Harald Kugel Christo Pantev Ren J. Huster 《Human brain mapping》2013,34(7):1501-1514
Conflict monitoring and motor inhibition are engaged in the performance of complex tasks. The midcingulate cortex (MCC) has been suggested to detect conflicts, whereas the right inferior frontal cortex (IFC) seems to be of relevance for the inhibition process. The current experiment investigates the neural underpinnings of their interplay via a modified flanker paradigm. Conflict was manipulated by the congruency of flanking stimuli relative to a target (congruent vs. incongruent) and motor inhibition by a within‐trial response change of the initiated response (keep response vs. stop‐change). We used event‐related functional magnetic resonance imaging, decomposition with high model order ICA, and single trial analysis to derive a functional parcellation of the whole‐brain data. Results demonstrate the segmentation of the MCC into anterior and posterior subregions, and of the IFC into the pars opercularis, pars triangularis, and pars orbitalis. The pars opercularis and pars triangularis of the right IFC constituted the foundation of inhibition‐related networks. With high conflict on incongruent trials, activity in the posterior MCC network, as well as in one right IFC network was observed. Stop‐change trials modulated both the MCC as well as networks covering extended parts of the IFC. Whereas conflict processing and inhibition most often are studied separately, this study provides a synopsis of functionally coupled brain regions acting in concert to enable an optimal performance in situations involving interference and inhibition. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc. 相似文献