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81.
Joseph P Broderick Laura R Sauerbeck Tatiana Foroud John Huston Nathan Pankratz Irene Meissner Robert D Brown 《BMC medical genetics》2005,6(1):17
Background
Subarachnoid hemorrhage (SAH) due to ruptured intracranial aneurysms (IAs) occurs in about 20,000 people per year in the U.S. annually and nearly half of the affected persons are dead within the first 30 days. Survivors of ruptured IAs are often left with substantial disability. Thus, primary prevention of aneurysm formation and rupture is of paramount importance. Prior studies indicate that genetic factors are important in the formation and rupture of IAs. The long-term goal of the Familial Intracranial Aneurysm (FIA) Study is to identify genes that underlie the development and rupture of intracranial aneurysms (IA). 相似文献82.
Wolf-Gerald Hiller Harald Pasch Irene V. Lampe 《Macromolecular chemistry and physics.》1991,192(10):2487-2495
Copolymers of 4-chlorophenyl methacrylate and methyl methacrylate were prepared and investigated by 1H and 13C NMR spectroscopy. The copolymer composition, determined by chlorine analysis, 1H and 13C NMR, was found to be close to the initial composition of the monomer mixture. The sequence analysis was carried out by analyzing the methoxy signals of the 1H NMR spectra. Six out of ten tactic and compositional triads could be resolved. It was found that the copolymers are predominantly syndiotactic and the compositional and tactic triad populations are given. The aromatic carbon atoms are sensitive towards compositional and tactic sequence effects, which results in a switch of the order of the tactic signals at different aromatic carbon atoms. 相似文献
83.
Two forms of spatial navigation, piloting using external cues and dead reckoning using self-movement cues, are manifest in the outward and homeward trips of adult rats exploring from a home base. Here, the development of these two forms of spatial behavior are described for rats aged 14-65 days using a new paradigm in which a huddle of pups or an artificial huddle, a small heat pad, served as a home base on an open circular table that the rats could explore. When moving away from both home bases, the travel distance, path complexity, and number of stops of outward trips from the home base increased progressively with age from postnatal day 16 through 22. When returning to the home bases, the return trips to the home base were always more direct and had high travel velocities even though travel distance increased with age for the longest trips. The results are discussed in relation to the ideas that: (1) the pups pilot on the outward portion of their excursion and dead reckon on the homeward portion of their excursion, and (2) the two forms of navigation and associated spatial capacity are interdependent and develop in parallel and in close association with locomotor skill. 相似文献
84.
Jian Fei Wang Irene R. Kieba Jon Korostoff Tai Liang Guo Noboru Yamaguchi Harry Rozmiarek Paul C. Billings Bruce J. Shenker Edward T. Lally 《Microbial pathogenesis》1998,25(6):317-331
Pasteurella haemolyticaleukotoxin (LKT) is a member of the RTX family of pore-forming toxins that kill bovine immune cells. Several studies have suggested that RTX toxins kill target cells by the induction of apoptosis. In the present study, BL3 bovine leukaemia cells were exposed to LKT and assessed by molecular and flow cytometric techniques that measure different aspects of apoptotic cell death. The intoxicated cells demonstrated morphological, light scatter and Hoechst 33258 staining characteristics consistent with cells undergoing apoptosis. The cells also exhibited internucleosomal DNA fragmentation and poly (ADP-ribose) polymerase (PARP) cleavage, both indicators of apoptosis. LKT-treated cells bound annexin-V-FITC indicating that phosphatidylserine groups were translocated from the inner to the outer leaflet of the cell membrane. The effect of LKT on cells was dose dependent and inhibitable by incubation with anti-LKT monoclonal antibody. Finally, an early step for induction of apoptosis appears to be the binding of LKT to a β2 integrin since pre-incubating cells with anti-β2 integrin antibodies inhibited LKT-induced apoptosis. This study provides new insights into understanding the pathogenesis of bovine pasteurellosis and could lead to the development of both preventative and therapeutic strategies for disease management. 相似文献
85.
Stephane Palazzetti Marie-Jeanne Richard Alain Favier Irene Margaritis 《Revue canadienne de physiologie appliquée》2003,28(4):588-604
We hypothesized that overloaded training (OT) in triathlon would induce oxidative stress and damage on muscle and DNA. Nine male triathletes and 6 male sedentary subjects participated in this study. Before and after a 4-week OT, triathletes exercised for a duathlon. Blood ratio of reduced vs. oxidized glutathione (GSH/GSSG), plasma thiobarbituric acid reactive substances (TBARS), leukocyte DNA damage, creatine kinase (CK), and CK-MB mass in plasma, erythrocyte superoxide dismutase (SOD) activity, erythrocyte and plasma glutathione peroxidase (GSH-Px) activities, and plasma total antioxidant status (TAS) were measured before and after OT in pre- and postexercise situations. Triathletes were overloaded in response to OT. In rest conditions, OT induced plasma GSH-Px activity increase and plasma TAS decrease (both p < 0.05). In exercise conditions, OT resulted in higher exercise-induced variations of blood GSH/GSSG ratio, TBARS level (both p < 0.05), and CK-MB mass (p < 0.01) in plasma; and decreased TAS response (p < 0.05). OT could compromise the antioxidant defense mechanism with respect to exercise-induced response. The resulting increased exercise-induced oxidative stress and further cellular susceptibility to damage needs more study. 相似文献
86.
Rademakers R Melquist S Cruts M Theuns J Del-Favero J Poorkaj P Baker M Sleegers K Crook R De Pooter T Bel Kacem S Adamson J Van den Bossche D Van den Broeck M Gass J Corsmit E De Rijk P Thomas N Engelborghs S Heckman M Litvan I Crook J De Deyn PP Dickson D Schellenberg GD Van Broeckhoven C Hutton ML 《Human molecular genetics》2005,14(21):3281-3292
87.
Discrimination of single-copy IS6110 DNA fingerprints of Mycobacterium tuberculosis isolates by high-resolution minisatellite-based typing 总被引:9,自引:0,他引:9
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Seven isoniazid-resistant isolates with mutations in the NADH dehydrogenase (ndh) gene were molecularly typed by IS6110-based restriction fragment length polymorphism analysis. All seven isolates with the R268H mutation had identical 1.4-kb IS6110 fingerprints. High-resolution minisatellite-based typing discriminated five of these isolates; two isolates were identical. 相似文献
88.
Elisabet Costa Silvia Canudas Ivan Garcia-Bassets Silvia Pérez Irene Fernández Ernest Giralt Fernando Azorín M. Lluïsa Espinás 《Chromosome research》2006,14(5):515-526
SAP18 is a highly conserved protein that was proposed to be involved in multiple cellular processes from autophagy to gene
regulation and mRNA processing. In this paper we show that, in Drosophila, dSAP18 is a predominantly nuclear protein that associates to both chromosomes and the nuclear matrix. dSAP18 becomes nuclear
early during development, at the onset of cellularization, and remains so all through embryo development. dSAP18 is also nuclear
in salivary glands, ovaries and cultured S2 cells. Here we also show that dSAP18 forms a complex with the Drosophila homolog of pinin (dPnn), a protein factor involved in mRNA splicing. dSAP18-dPnn interaction was confirmed in vivo, through co-immunoprecipitation experiments, as well as in vitro, through GST pull-down assays. These results are discussed in the context of the possible functions played by SAP18. 相似文献
89.
Harder L Gesk S Martin-Subero JI Merz H Hochhaus A Maass E Feller A Grote W Siebert R Fetscher S 《Cancer Genetics and Cytogenetics》2003,142(1):80-82
We describe a patient initially diagnosed with a chronic myeloproliferative disorder in the accelerated phase. Cytogenetic analysis showed the presence of two independent clones. One clone contained a typical Philadelphia (Ph) chromosome due to t(9;22)(q34;q11), as the sole abnormality which was proven molecularly to result in the b2a2-BCR/ABL fusion. The other clone displayed a complex karyotype with several structural and numerical aberrations including trisomy 11 and 22 but lacking a t(9;22) or any other structural abnormalities involving chromosomes 9 and 22. Fluorescence in situ hybridization demonstrated that the t(9;22) was present only in cells with two copies of chromosomes 11 and 22. In contrast, cells with trisomies 11 and 22 lacked evidence for a BCR/ABL fusion. Based on the genetic findings, simultaneous chronic and acute myelocytic leukemias were diagnosed rather than a blastic phase of a chronic myelocytic leukemia. 相似文献
90.
Harder A Jendroska K Kreuz F Wirth T Schafranka C Karnatz N Théallier-Janko A Dreier J Lohan K Emmerich D Cervós-Navarro J Windl O Kretzschmar HA Nürnberg P Witkowski R 《American journal of medical genetics》1999,87(4):311-316
We present a novel large German kindred of fatal familial insomnia (FFI) consisting of three branches and comprising more than 800 individuals of 12 generations, the largest pedigree of any familial prion disease known today. There is a wide spectrum of clinical presentations leading to misdiagnoses of Olivo-Ponto-Cerebellar Atrophy (OPCA), Parkinson's or Alzheimer's disease in addition to Creutzfeldt-Jakob disease (CJD) and Gerstmann-Str?ussler-Scheinker (GSS) syndrome. Molecular genetic analysis of the prion protein gene (PRNP) confirmed the mutation D178N segregating with methionine at the polymorphic codon 129 of PRNP in all 7 patients examined. This polymorphism at codon 129 is supposed to discriminate between familial CJD (fCJD) and FFI; the 129M allele determines FFI and 129V fCJD. Furthermore, heterozygosity at this site appears to induce prolonged disease duration as compared to the homozygous condition. The variability of the clinical and pathological findings documented for our patients indicates the difficulty in establishing the diagnosis of FFI on clinical and on pathological grounds alone. In three cases (IX-97, XI-21, V-2) followed up by us prospectively insomnia was an early and severe symptom; however, in case notes analyzed retrospectively this symptom was frequently missed. In contrast to previous reports and in agreement with recent studies we cannot confirm a clear relationship between the status of the M/V polymorphism at codon 129 and the age-of-onset of this disease. 相似文献