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131.
OBJECTIVE: This study evaluates a patient education programme focussed on improving communication and stress management skills among couples in fertility treatment. METHODS: In total, 37 couples completed the intervention. Two teachers conducted all the five courses offered. The effectiveness regarding communication and infertility-related stress was assessed by questionnaires immediately before (time T1) and after the intervention (time T2). Seeking of information and professional support was assessed at a 12-month follow-up (time T3); response rates were: T1, 93.2%; T2, 85.1%; T3, 74.3%. Data were compared at baseline (T1) and at the 12-month follow-up (T3) with a prospective cohort of Danish people in fertility treatment. RESULTS: There were no differences in infertility-related stress at base line between the two groups studied. We estimated the bi-directional changes in communication, e.g., changes from talking often to talking less frequently and vice versa. More intervention participants started to talk often with their partner about infertility and its treatment after the intervention compared to those who stopped to talk often. Women and men changed occurrence, frequency and content of communication with close other people. Among women marital benefit increased significantly. Infertility-related stress was not reduced significantly. Significantly more intervention participants than in the comparison group had contacted support groups, a psychologist and/or agencies for adoption at the 12-month follow-up. CONCLUSION: The intervention resulted in important perceived improvement in the participants' competence to actively manage changes in marital communication and in communication in different social arenas. PRACTICE IMPLICATIONS: We recommend fertility clinics to develop and evaluate different interventions for those fertility couples who ask for more psychosocial support.  相似文献   
132.
The authors have recently developed a monoclonal antibody, HHF35, that recognizes the muscle-specific isoforms of actin. To determine its potential usefulness in the differential diagnosis of "small, round, blue cell" tumors of childhood, they immunolabeled formalinor B-5-fixed tissue sections from known cases of rhabdomyosarcoma or rhabdomyoma (30), neuroblastoma (9), retinoblastoma (2), and Ewing's sarcoma (9) with HHF35 and with antibodies to creatine kinase M, myoglobin, vimentin, and neuron-specific enolase. HHF35 reacted with 29 of 30 cases of rhabdomyosarcoma, whereas antibodies to creatine kinase M and myoglobin were positive on only 12 and 7 tumors, respectively. HHF35 did not react with any case of neuroblastoma, retinoblastoma, or Ewing's sarcoma when the antibody diluent contained 50 mM EDTA. These results indicate that HHF35 is a highly sensitive and specific marker for myogenic differentiation and that it will be useful in the differential diagnosis of rhabdomyosarcomas.  相似文献   
133.
Direct immunofluorescence and direct immunoperoxidase staining were equally sensitive and specific for detection of herpes simplex virus antigen in lesion specimens, and each method showed 82% agreement with virus isolation results.  相似文献   
134.
Mouse L(tk-) cells were transfected with recombinant genomic clones encoding the human major histocompatibility antigens HLA-A2 or HLA-B7. The exposure of 15 different transfected cell clones to mouse interferon resulted in an up to 2.9-fold enhancement of the HLA-A2 antigen at the cell surface but in an up to 5.5-fold enhancement of the HLA-B7 antigen as shown by quantitative radioimmunoassay with monoclonal antibodies directed against different HLA epitopes. Using the HLA-Bw6 specific monoclonal antibody 2BC4, an even higher increase of the HLA-B7 antigen (up to 12-fold) could be observed. This higher inducibility of an HLA-B versus HLA-A locus gene may reflect distinct regulatory mechanism controlling the expression of HLA class I subregion antigens.  相似文献   
135.
Characterization of pili associated with Escherichia coli O18ac.   总被引:5,自引:15,他引:5       下载免费PDF全文
A strain of Escherichia coli O18ac isolated from the stool sample of a patient with diarrhea was found to agglutinate human erythrocytes. From the results presented it is suggested that this hemagglutination is mediated by pili. Isolated pilus preparations agglutinated human erythrocytes, whereas pilus-negative mutants did not. The serological and chemical analyses indicate that the pili associated with E. coli O18ac are distinct from other types found with E. coli.  相似文献   
136.
IgE mediates its effector functions through the Fc region and it has been demonstrated that structures in the Cvarepsilon3-domain are crucial for FcvarepsilonR-binding. In order to further study structures of importance for the function of IgE, such as the carbohydrates, fragments with unmodified amino acid sequence were blunt-end cloned and expressed in baculovirus-infected Sf9 cells. Two fragments of human IgE, one encompassing the entire Fc-region (rCvarepsilon2-4) and a smaller one comprising the second and third domain (rCvarepsilon2-3), were produced and characterised with respect to epitope expression, glycosylation and FcvarepsilonR-binding. N-terminal analysis showed the expected VCSRDF-sequence of the Cvarepsilon2-domain, confirming correct cleavage of the secretion signal. Immunoblotting and gel permeation chromatography demonstrated that rCvarepsilon2-4 mainly formed a dimer, whereas rCvarepsilon2-3 also existed as monomers and oligomers. Endoglycosidase-treatment revealed that both fragments were N-glycosylated. In inhibition ELISA, rCvarepsilon2-4 and myeloma protein IgE(DES) reacted in a near equimolar way with monoclonal antibodies against the Cvarepsilon2-, Cvarepsilon3- and Cvarepsilon4-domains, whereas rCvarepsilon2-3 only reacted with anti-Cvarepsilon2 mAbs. Moreover, in FACS analysis rCvarepsilon2-4 interacted with two cell-lines constitutively expressing FcvarepsilonRI or FcvarepsilonRII, whereas rCvarepsilon2-3 lacked reactivity. A substantial reduction in the ability of rCvarepsilon2-4, following endoglycosidase treatment, to react with recombinant alpha-chain of the high affinity receptor for IgE in sandwich ELISA, indicated a role of N-linked oligosaccharides in stabilising receptor binding structures. Taken together, our results show that rCvarepsilon2-4, but not rCvarepsilon2-3, will be useful in studies of structure-function relationships of IgE, including the role of N-glycosylation, since it demonstrated appropriate epitope expression, conformation and ability to bind Fcvarepsilon-receptors.  相似文献   
137.
The slowing of impulse conduction during the relative refractory period has often been used to assess activation of C-fibers, in particular, in human microneurography. This study aimed to evaluate the sensitivity of this method and the factors affecting it. Thirty cutaneous C-fibers were recorded from the peroneal nerves of healthy human subjects. Intracutaneous electrical stimulation in the receptive field at 4 s intervals, after some minutes of adaptation, induced spike discharges at constant latency. One or more conditioning stimulus pulses were interpolated at different intervals and the increase in latency after the subsequent regular pulse was assessed. The latency shift was found to depend on the number of interposed pulses, on the time interval between conditioning and conditioned stimulus, and on the conduction velocity of the C-unit. The increase in latency was larger with greater distance between stimulating and recording electrodes, indicating a contribution of the conductile membrane over its whole length. On the other hand, slowing was more pronounced, on average, in slower conducting C-units and conduction velocities were slower when recordings were performed more distally. These findings indicate that the slower terminal nerve branches contribute most to the latency increases. Even a single additional spike in between two regular pulses caused a reliable latency shift of 1.2±0.2 ms (mean ±SEM) and additional pulses lead to an approximately linear latency increase (2 pulses: 2.3±0.3 ms; 4 pulses: 5.9±0.7 ms). In contrast to the number of interposed stimuli, different intervals between interposed and regular stimuli had only a minor impact on the latency shifts. It is concluded that latency shifts are reliable indicators of C-fiber activation, being sensitive enough to detect even single spike responses. Furthermore, latency increases may be used as a relative measure of C-fiber activation, e.g., when comparing responses to stimuli of different strength.  相似文献   
138.
Enteropathogenic Yersinia sp. releases plasmid-associated proteins of low molecular mass (26-67 kilodaltons) at 37 degrees C. In this study, the optimum conditions for the release of proteins were assessed and the released proteins (RPs) were analyzed for the manner of release, immunochemical characteristics, and the location of the genes necessary for their synthesis. Protein release was strongly enhanced when growth media were markedly depleted of calcium ions by precipitation with oxalate or chelation with EGTA [ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid]. RP yields were greatest when Yersinia spp. were in the exponential growth phase. The RPs appeared to be released from the Yersinia spp. by secretion rather than by pinching off of membrane vesicles, because the RPs did not sediment during high-speed centrifugation nor were they contaminated to any significant degree with lipopolysaccharide. Moreover, immunoblot analysis revealed only traces of protein species related to RPs within the outer membranes of plasmid-positive Yersinia spp. grown at 37 degrees C under calcium-restricted conditions. Immunoblot studies also showed that the RPs of Y. enterocolitica serotypes O:3, O:8, and O:9 and the RP of Y. pseudotuberculosis serotype I are highly cross-reactive. Finally, the immunoprecipitates of the products of minicells which harbor Yersinia plasmids were used to demonstrate that at least three proteins immunochemically related to the released fraction were plasmid encoded. These results suggest that at least three of the RPs may be related to or identical with previously described plasmid-encoded Yersinia outer membrane proteins.  相似文献   
139.
Comoviruses are a group of plant viruses in the picornavirus superfamily. The type member of comoviruses, cowpea mosaic virus (CPMV), was crystallized in the cubic space group I23, a = 317 A and the hexagonal space group P6(1)22, a = 451 A, c = 1038 A. Structures of three closely similar nucleoprotein particles were determined in the cubic form. The roughly 300-A capsid was similar to the picornavirus capsid displaying a pseudo T = 3 (P = 3) surface lattice. The three beta-sandwich domains adopt two orientations, one with the long axis radial and the other two with the long axes tangential in reference to the capsid sphere. T = 3 viruses display one or the other of these two orientations. The CPMV capsid was permeable to cesium ions, leading to a disturbance of the beta-annulus inside a channel-like structure, suggesting an ion channel. The hexagonal crystal form diffracted X rays to 3 A resolution, despite the large unit cell. The large ( approximately 200 A) solvent channels in the lattice allow exchange of CPMV cognate Fab fragments. As an initial step in the structure determination of the CPMV/Fab complex, the P6(1)22 crystal structure was solved by molecular replacement with the CPMV model determined in the cubic cell.  相似文献   
140.
A hematogenic invasion of the brain in suckling NMRI mice infected with Trypanosoma brucei rhodesiense was initiated by means of a mechanical damage of the blood-brain barrier. The brain was punctured after development of a blood infection. Brain infection was found in 31 out of 32 animals examined. Trypanosomes are initially capable of rapid multiplication. The number of parasites was highest during the 1st week. From the middle of the 2nd week the number of parasites decreased continuously, alongside increasing atrophy. In the 3rd and 4th week only rare degenerating or ghost trypanosomes were present. No reactions were detected in the glial and mesenchymal cells. It is presumed that the short phase of trypanosome multiplication is due to the temporary collateral oedema of the brain tissue. The decrease in parasites from the 2nd week onwards is mainly attributed to natural death due to particular anatomical features of the brain tissue. These are also responsible for the absence of defensive inflammatory reactions, based on the hypothesis that contact between trypanosomes and the cells of the brain blood vessels is prevented.  相似文献   
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