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11.
A mutated intron sequence codes for an antigenic peptide recognized by cytolytic T lymphocytes on a human melanoma. 总被引:17,自引:0,他引:17
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P G Coulie F Lehmann B Lethé J Herman C Lurquin M Andrawiss T Boon 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(17):7976-7980
We have identified an antigen recognized on a human melanoma by autologous cytolytic T lymphocytes. It is encoded by a gene that is expressed in many normal tissues. Remarkably, the sequence coding for the antigenic peptide is located across an exon-intron junction. A point mutation is present in the intron that generates an amino acid change that is essential for the recognition of the peptide by the anti-tumor cytotoxic T lymphocytes. This observation suggests that the T-cell-mediated surveillance of the integrity of the genome may extend to some intronic regions. 相似文献
12.
M. Puka-Sundvall E. Gilland E. Bona A. Lehmann M. Sandberg H. Hagberg 《Metabolic brain disease》1996,11(2):109-123
The aim of this study was to investigate the possible role of excitatory amino acids (EAAs) and cysteine in the development of brain damage after hypoxia-ischemia (HI) in neonates. In a rat model of neonatal HI, changes in extracellular (ec) amino acids in cerebral cortex were measured with microdialysis and correlated with the extent of brain damage at the site of probe placement. Extracellular concentrations of glutamate, aspartate and cysteine increased during HI and remained elevated during reperfusion. During HI the pattern of EAA changes was the same in the infarcted, undamaged and border zone regions. During reperfusion, however, the ec concentrations of glutamate, aspartate and cysteine were higher in infarcted and border zone areas compared to undamaged tissue. HI also produced a slight increase of tissue concentration of cysteine and decrease of tissue concentration of glutamate in parietal cortex of the HI hemisphere. The effect of cysteine on brain damage induced by HI and glutamate was also investigated. A subtoxic dose of cysteine potentiated glutamate toxicity in the arcuate nucleus and enhanced brain infarction after HI in neonatal rats. The results show that in neonatal HI the extracellular levels of EAAs during HI are not directly related to brain injury but the EAA levels during reflow predict the extent of infarction. Cysteine increases HI-induced brain injury and potentiates glutamate toxicity in neonatal rats. Speculatively, elevated level of cysteine during reperfusion may participate in the excitotoxic cascade leading to brain injury. 相似文献
13.
Photopatch testing: a consensus methodology for Europe 总被引:1,自引:0,他引:1
D.P. Bruynzeel J. Ferguson K. Andersen M. Gonçalo John English A. Goossens E. Holzle S.H. Ibbotson M. Lecha P. Lehmann F. Leonard Harry Moseley P. Pigatto A. Tanew 《Journal of the European Academy of Dermatology and Venereology》2004,18(6):679-682
A group of interested European Contact Dermatologists/Photobiologists met to produce a consensus statement on methodology, test materials and interpretation of photopatch testing. While it is recognized that a range of local variables operate throughout Europe, the underlying purpose of the work is to act as an essential preamble to a Pan European Photopatch Test Study focusing particularly on sunscreen chemicals. 相似文献
14.
Ohne ZusammenfassungDie vorliegenden Untersuchungen wurden zum Teil mit Mitteln der Deutschen Forschungsgemeinschaft ausgeführt, der wir unseren Dank aussprechen. 相似文献
15.
Case report: Fatal hepatic failure after aortic valve replacement and sevoflurane exposure 总被引:1,自引:0,他引:1
Andreas Lehmann Michael Neher Arndt-Holger Kiessling Frank Isgro Anette Koloska Joachim Boldt 《Journal canadien d'anesthésie》2007,54(11):917-921
PURPOSE: To report a case of lethal hepatotoxicity possibly caused by sevoflurane. CLINICAL FEATURES: A 76-yr-old woman with a history of four previous minor surgical procedures developed acute liver failure after general anesthesia with sevoflurane, sufentanil and propofol for aortic valve replacement. After an uneventful procedure the patient was extubated 4.5 hr after surgery. On the second postoperative day, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) increased. On the third postoperative day liver failure occurred, ALT peaked at 10504 UxL(-1) and AST at 15516 UxL(-1), and coagulopathy with an international normalized ratio of 4.6 developed. Liver transplantation was considered but rejected as a therapeutic option. The patient died three days after the operation in multiple organ failure triggered by hepatic failure. Other possible causes for liver failure were excluded. CONCLUSIONS: Sevoflurane hepatitis as a cause for liver failure may be implicated in this patient undergoing valve surgery. Unlike other halogenated anesthetic drugs, sevoflurane is not metabolized to hepatotoxic trifluoroacetyl proteins. However, compound A may react with proteins and may be transformed into antigenic material. We suggest that all halogenated anesthetics may be implicated with acute liver injury. 相似文献
16.
Thorsten Grund Konrad Lehmann Nathalie Bock Aribert Rothenberger Gertraud Teuchert-Noodt 《Behavioral and brain functions : BBF》2006,2(1):2-14
Methylphenidate (MPH) is the most commonly used drug to treat attention deficit/hyperactivity disorder (ADHD) in children
effectively and safely. In spite of its widespread application throughout one of the most plastic and sensitive phases of
brain development, very little is known to date about its long-term effects on brain structure and function. Hence, this short
review updates the influence of MPH on brain development, since recent human and animal studies suggest that MPH alters the
dopaminergic system with long-term effects beyond the termination of treatment. 相似文献
17.
18.
Photocarcinogenesis and inhibition of intercellular adhesion molecule 1 expression in cells of DNA-repair-defective individuals
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19.
The partition coefficients of three homologous anticonvulsant phenylalkylamides [racemic alpha-hydroxy-alpha-ethyl-alpha-phenylacetamide (HEPA); beta-hydroxy-beta-ethyl-beta-phenylpropionamide (HEPP); and gamma-hydroxy-gamma-ethyl-gamma-phenylbutyramide (HEPB)] were determined by reversed-phase high-performance liquid chromatography (RP-HPLC). The system was calibrated with a series of simple amines and amides, using their published log P values. The log kw values (methanol:water, extrapolated to 100% water) were 1.260 for HEPA, 1.670 for HEPP, and 1.852 for HEPB. From these results, the partition coefficients (log P) were calculated by regression as 1.20, 1.83, and 2.11, respectively. The log P values were essentially equal to those calculated by the Leo-Hansch fragmental method. Since the potency of the three anticonvulsants is approximately the same in a variety of tests, no dependence on lipophilicity could be established. 相似文献
20.
Infectious agents have often been implicated in the etiology of autoimmune diseases. Here we show that bacteria may also play a role in resistance to autoimmune diseases. SJL/J and (SJL/J x BALB/c)F1 mice are genetically susceptible to induction of experimental autoimmune encephalomyelitis (EAE), a murine model for human demyelinating autoimmune diseases such as multiple sclerosis. We studied the effect of several bacteria on the development of EAE and found that exposure of SJL/J or (SJL/J x BALB/c)F1 mice to Mycobacterium tuberculosis or Bordetella pertussis consistently rendered mice highly refractory to subsequent induction of the disease. Other bacteria such as Escherichia coli, Shigella and Staphylococcus aureus were found to be less effective, or were protective only if specific immunization procedures were used. Furthermore, M. tuberculosis and B. pertussis were protective irrespective of the route of administration and minute amounts (as low as 0.5 micrograms) of M. tuberculosis were sufficient to protect EAE-susceptible mice against induction of the disease. Interestingly, these bacteria, which are commonly used to promote development of EAE, conferred the highest degree of protection against the disease. The M. tuberculosis-induced protection was found to be associated with active suppression mechanisms mediated by T lymphocytes capable of transferring protection to naive syngeneic mice. These findings indicate that certain bacteria may protect against the development of autoimmune diseases. These results also suggest the potential use for still-unidentified bacterial agents in the manipulation of certain autoimmune diseases. 相似文献