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31.
Immunoblot analysis of the serological response in Hantavirus infections   总被引:3,自引:0,他引:3  
Sera from patients with nephropathia epidemica (NE) or Korean hemorrhagic fever (KHF) were tested for specific antibody response to antigens of H?lln?s virus and Hantaan virus strain 76-118. A Vero E6 derived cell line persistently infected with H?lln?s virus strain B1, and Vero E6 cells freshly infected with Hantaan virus type strain 76-118 were used as antigens in the immunofluorescence assay (IFA) and the immunoblot. Blots were prepared from whole cell lysates. The convalescent-phase sera of NE patients tested in this study regularly revealed a marked reaction with a 52 kilodalton (Kd) protein of H?lln?s virus and a 50 Kd protein of Hantaan virus. A convalescent serum from a patient with Korean hemorrhagic fever and a rat antiserum against Hantaan virus could recognize the 50 Kd band of Hantaan virus but showed no apparent reactivity with the 52 Kd component of H?lln?s virus in the standard dilutions. Some sera could additionally identify minor bands in the 55 Kd and/or 67 Kd region of the blots. A one-way cross reactivity between Hantaan and H?lln?s viruses was also evident from the results of the immunofluorescence assays in that NE convalescent sera reacted with both viruses, whereas KHF convalescent or anti-Hantaan sera gave strongly positive results with Hantaan virus but only faint reaction with H?lln?s virus.  相似文献   
32.
The molecular epidemiology of molluscum contagiosum virus (MCV) infections was investigated by restriction endonuclease analysis of the genomes of 222 separate isolates collected from 147 patients living in Germany (33 patients), Hong Kong (6 patients), and Scotland (108 patients). MCV type 1 (MCV-1) caused 96.6% of the infections, and MCV type 2 (MCV-2) caused 3.4%. However, isolates from four of the 142 MCV-1-infected patients and two of the five MCV-2-infected patients showed minor differences in their DNA restriction patterns because of the loss of a single or very few recognition sites for the enzymes used. No genome variations were detected amongst isolates collected from different sites or on several occasions from individual patients or from closely related patients. Southern blot hybridization revealed a high level of relatedness between MCV-1 and 2. No differences were seen in the appearance or anatomical localization of lesions caused by either virus type. In particular, there was no preferred genital localization for MCV-2 infections.  相似文献   
33.
The authors investigated the influence of human body inhomogeneities such as the lungs, blood masses and the skeletal muscle layer on the electrical body surface potential and the magnetic field. The surface potentials and magnetic fields are calculated using a boundary element method. As a rule the blood masses have a large influence on both potential and magnetic field amplitude as well as on the potential and magnetic field map orientation, but the influence on the topology of the map is less in the electric case than in the magnetic case. The single-dipole reconstruction was applied to estimate the error caused by neglecting inner inhomogeneities in source localization. The neglect of lungs and blood masses results in a localization error of less than 1 cm in the electric case but more than 1 cm for deep sources at the posterior side of the heart in the magnetic case. The authors tried to assess the influence of the skeletal muscle layer by both an analytical two-layered anisotropic half-space model and the torso extension method. The skeletal muscle layer causes a smoothing effect on the electrical surface potential and to a lesser extent on the magnetic field, leading to an overestimation of the actual source depth of about 1-2 cm. In principle this can be reduced by taking data from all over the thoracic surface. The authors designed experiments for simultaneous measurement of body surface potential and extracorporeal magnetic field from the same subject. The evaluation of data from two patients showing Wolff-Parkinson-White syndrome has shown that localization results from electric potential data and magnetocardiographic data are consistent.  相似文献   
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In an enzyme-specific drug screening system nalidixic acid and 3'FTdR, inhibitors of DNA synthesis, both reduce the growth of wild type and temperature-sensitive point mutants of phage T3 with different efficiencies. The wild type shows the strongest sensitivity against the drugs, while an exonuclease mutant is the most insensitive variant. The DNA polymerase mutants exhibit an intermediate degree of inhibition. The anthracycline antibiotics violamycin BI and adriblastin which preferentially inhibit RNA synthesis show the same degree of inhibition for all mutants. This is true also for the RNA synthesis inhibitor lambdamycin, which is identical with chartreusin. The protein synthesis inhibitors chloramphenicol and o-phenanthroline, a chelating agent, impair all mutants to the same extent. Our data confirm the hypothesis that structural variants of essential viral enzymes, when compared with the wild type should sensitivities against specific inhibitors and show that this T3 system could be used for the indication of specific inhibitors of DNA synthesis.  相似文献   
36.
In this study the influence of special memory tasks, the effect of cues and the influence of the severity of the disease on the performance of short-term memory of patients suffering from Huntington's disease was examined. Stimulus material consisted of 30 nouns for reproduction and 20 nouns to be subsumed to 5 categories. Depending on experimental condition, assistance was given or withheld. 16 healthy subjects and 48 patients suffering from Huntington's disease took part in the study. Between these groups there was a significant effect of the factor "memory task." Furthermore, it could be demonstrated that the performance level decreases and differences between individuals increase with increasing severity of the disease. There was no significant effect of the factor "cues."  相似文献   
37.
K C Scholz 《Orthopedics》1987,10(1):125-131
When conservative measures fail to alleviate pain and disability of ankle joint disease, tibiotalar arthrodesis is the present accepted surgical treatment. Unfortunately, ankle arthrodesis also carries a significant rate of complications and the success rate does not parallel the results of hip and knee joint arthroplasties. A large percentage of ankle arthrodeses remain painful, and function is not normal. There is no satisfactory "salvage procedure" to a painful ankle fusion. Patients with primary ankle arthritis tend to develop bilateral ankle involvement as well as involvement of the subtalar and midtarsal joints; bilateral ankle fusion results in a severe handicap to gait and function. Ankle fusion with involvement of the subtalar or midtarsal joints might well result in a painful fusion. Maintenance of tibiotalar motion appears essential in both instances. It is apparent that all ankle problems cannot be dealt with by fusion and a successful long-term ankle arthroplasty is needed. Total ankle arthroplasty using cement fixation remains controversial. Continued use of polymethylmethacrylate and additional design changes do not appear to be the answer to possible ankle joint replacement. Initial success using the PCA concept of biological cementless fixation of the Scholz total ankle prosthetic components appears to offer a new dimension in the success of total ankle arthroplasty.  相似文献   
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The mitochondrial pyruvate carrier (MPC) resides in the mitochondrial inner membrane, where it links cytosolic and mitochondrial metabolism by transporting pyruvate produced in glycolysis into the mitochondrial matrix. Due to its central metabolic role, it has been proposed as a potential drug target for diabetes, non-alcoholic fatty liver disease, neurodegeneration, and cancers relying on mitochondrial metabolism. Little is known about the structure and mechanism of MPC, as the proteins involved were only identified a decade ago and technical difficulties concerning their purification and stability have hindered progress in functional and structural analyses. The functional unit of MPC is a hetero-dimer comprising two small homologous membrane proteins, MPC1/MPC2 in humans, with the alternative complex MPC1L/MPC2 forming in the testis, but MPC proteins are found throughout the tree of life. The predicted topology of each protomer consists of an amphipathic helix followed by three transmembrane helices. An increasing number of inhibitors are being identified, expanding MPC pharmacology and providing insights into the inhibitory mechanism. Here, we provide critical insights on the composition, structure, and function of the complex and we summarize the different classes of small molecule inhibitors and their potential in therapeutics.  相似文献   
40.
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