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1.
Regional cerebral blood flow (rCBF) was assessed by means of HMPAO-SPECT in two experimental groups. In a control condition both groups listened to abstract words, in the experimental condition they heard five names of objects. One group was advised to form visual images of the objects, the other group was advised to form acoustic images of the sounds made by these objects. Post-experimental questionnaires revealed that most of the subjects in the acoustic imagery condition had had visual images in addition to the acoustic ones. Both imagery conditions lead to approximately equal increases of rCBF in the left inferior occipital region and in the left thalamus. Flow increases in both hippocampal regions and the right inferior and superior temporal regions were larger in the acoustic than in the visual imagery condition. It is concluded that only the activation of left inferior occipital and left thalamic regions can be interpreted as being related to modality-specific visual aspects of imagery. 相似文献
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L. Smith-Seemiller M. R. Lovell M. D. Franzen S. S. Smith R. N. Townsend 《Brain injury : [BI]》1997,11(10):735-742
It is known that using seatbelts reduces the incidence and severity of closed head injury CHI from motor vehicle crashes. One would expect unrestrained occupants in motor vehicle crashes to suffer more severe CHIs than restrained occupants, as reflected by Glasgow Coma Scale GCS scores. One might also expect an increased risk of focal injury due to contact forces in unrestrained occupants. The purpose of this study was to test the hypothesis that failure to use seatbelts results in increased severity of neuropsychological sequelae, even with GCS controlled. We also examined the impact of demo graphic variables on seatbelt use. Subjects included patients admitted to a hospital trauma service who were suspected of having suffered CHI. All patients completed neuropsychological testing, which was entered into a data base along with demographic and clinical information. People who had docu mented use of seatbelt restraints were compared with those who were unrestrained. Results confirmed that certain demographic variables are associated with the use of seatbelts. Results also suggested that failure to use seatbelt restraints is associated with more severe impairment on tests that are sensitive to frontal lobe dysfunction. 相似文献
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CG Teo 《Oral diseases》2002,8(S2):88-90
Oral hairy leukoplakia (OHL) and Kaposi's sarcoma (KS) are commonly encountered in the HIV-infected patient. A unique feature of OHL is non-cytolytic high level of replication of Epstein–Barr virus (EBV) in the glossal epithelium. The expression of viral-encoded anti-apoptotic proteins concomitant to replicative proteins probably underlies this phenomenon. The question of whether OHL arises from activation of EBV latent in the tongue, or from superinfection by endogenous EBV shed via non-glossal sites or by exogenous EBV remains unresolved. Human herpesvirus 8 (HHV8) is now seen as necessary but not sufficient cause of KS. Expression of HHV8-encoded oncogenic proteins in endothelial cells probably explains the aberrant proliferation of these cells in KS lesions. Studies into why KS is so commonly observed at the palate in HIV-infected patients may provide important clues to its pathogenesis. 相似文献
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Endocarditis caused by Gemella haemolysans 总被引:2,自引:0,他引:2
Summary
Gemella haemolysans, a coccus related to theStreptococcaceae, was isolated from the blood of a patient with endocarditis. The patient was successfully treated with a combination of penicillin G and tobramycin, followed by clindamycin. The taxonomy of this organism, especially its relationship toStreptococcus morbillorum is discussed and previously reported cases ofGemella infections are reviewed.
Endokarditis durch Gemella haemolysans
Zusammenfassung Aus Blutkulturen einer Patientin mit einer Endokarditis wurde einGemella haemolysans-Stamm angezüchtet, ein zu denStreptococcaceae gehöriges Bakterium. Die Patientin konnte mit einer Kombination von Penicillin G und Tobramycin sowie anschließender Clindamycin-Therapie erfolgreich behandelt werden. Die Taxonomie des Erregers, insbesondere seine Verwandtschaft zuStreptococcus morbillorum, wird diskutiert und eine Übersicht über kürzlich beschriebeneGemella-Infektionen gegeben.相似文献
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Blinded, Externally Controlled Multicenter Evaluation of Light Microscopy and PCR for Detection of Microsporidia in Stool Specimens 总被引:6,自引:4,他引:6
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Heinz Rinder Klaus Janitschke Horst Aspck Alexandre J. Da Silva Peter Deplazes Daniel P. Fedorko Caspar Franzen Ursula Futh Frank Hünger Anselm Lehmacher Christian G. Meyer Jean-Michel Molina Jrg Sandfort Rainer Weber Thomas Lscher the Diagnostic Multicenter Study Group on Microsporidia 《Journal of clinical microbiology》1998,36(6):1814-1818
The quality parameters for the detection of microsporidia in identical sets of 50 stool samples were determined for six laboratories where technicians used light microscopy and for six laboratories where technicians used PCR. The average overall sensitivities were 67% (89% for patient samples only) for the PCR laboratories and 54% (80% for patient samples only) for the light microscopy laboratories. Specificities were 98 and 95%, respectively. Differences in results were most apparent between the individual laboratories rather than between the two major methods used. 相似文献
9.
Ribosomal RNA of Nosema algerae and phylogenetic relationship to other microsporidia 总被引:1,自引:0,他引:1
Microsporidia are intracellular parasites that are common in invertebrates. Taxonomic classification is mostly restricted
to morphologic and physiologic data. Limited data are available about taxonomic classification using DNA-sequence data for
analysis. We examined the small-subunit (SSU) rDNA, the intergenic spacer (ITS) region, and a part of the large-subunit (LSU)
rDNA of Nosema algerae, a parasite of mosquitoes, taken from a laboratory colony of Anopheles stephensi. Target gene amplifications were done by polymerase chain reaction (PCR) and, after cloning, DNA fragments were sequenced.
The SSU-rDNA sequence obtained was aligned with several other microsporidian SSU-rDNA sequences available from the GenBank
or EMBL data bases and was analyzed by different methods. On the basis of the results of our phylogenetic analysis, we suggest
that our N. algerae isolate is not closely related to other microsporidia belonging to the genus Nosema.
Received: 31 May 1999 / Accepted: 27 July 1999 相似文献
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