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81.
Mycosis fungoides is a T-cell lymphoma that arises in the skin and progresses at highly variable rates. Nonradomized studies have suggested that early aggressive therapy may improve the prognosis in this usually fatal disease. We studied 103 patients with mycosis fungoides, who, after complete staging, were randomly assigned to receive either combination therapy, consisting of 3000 cGy of electron-beam radiation to the skin combined with parenteral chemotherapy with cyclophosphamide, doxorubicin, etoposide, and vincristine (n = 52) or sequential topical treatment (n = 51). The prognostic factors were well balanced in the two groups. Combined therapy produced considerable toxicity: 12 patients required hospitalization for fever and transient neutropenia, 5 had congestive heart failure, and 2 were later found to have acute nonlymphocytic leukemia. Patients receiving combined therapy had a significantly higher rate of complete response, documented by biopsy, than patients receiving conservative therapy (38 percent vs. 18 percent; P = 0.032). After a median follow-up of 75 months, however, there was no significant difference between the treatment groups in disease-free or overall survival. We conclude that early aggressive therapy with radiation and chemotherapy does not improve the prognosis for patients with mycosis fungoides as compared with conservative treatment beginning with sequential topical therapies.  相似文献   
82.
83.
RNA-RNA tissue in situ hybridization is a relatively new technique that detects gene expression in individual cells. In this report we compare and contrast the technique with conventional biologic analysis. We illustrate how this technique could function as a diagnostic tool by applying it to a 58-year-old man with a four-month history of lymphadenopathy and peripheral lymphocytosis. RNA-RNA tissue in situ hybridization performed on sections of one of this patient's lymph nodes and on cytospins of his peripheral blood demonstrated the presence of an apparent monoclonal population of B cells producing mu and lambda immunoglobulin (Ig) messages in the lymph node and peripheral blood as well as a T-cell population in the lymph node only. These results were corroborative and complementary to conventional DNA (Southern) and RNA (Northern) analyses. The data were consistent with the diagnosis of chronic lymphocytic leukemia (CLL). With the use of this technique, an intriguing pattern of cellular heterogeneity was observed within the mu-lambda population of cells in the lymph node. A subset of these cells appeared to express a much greater amount of immunoglobulin message and to cluster around the lymph node vessels. The combination of RNA-RNA in situ hybridization and routine histopathology has the potential for providing an additional dimension to tumor analysis.  相似文献   
84.
Anti-IgE- and Con A-induced histamine release from serosal mast cells were compared to each other and to total serum levels of IgE in non-immunized, alum-injected, and Silica gel-injected rats of the BN, Fischer, PVG, and SD strains. The results indicate that the degree of anti-IgE-and Con A-induced release is strain-dependent and varies with immunization conditions. Furthermore, there is a gross but not complete correlation between the degree of serosal mast cell histamine release induced by the two secretagogues. However, Con A- or anti-IgE-induced release could significantly be correlated to serum levels of total IgE only in the Fischer strain but not in the BN or the PVG strains. In the SD strain, Con A-induced release correlated to serum IgE levels in Silica gel-injected but not in alum-injected animals.Subsidiary of AB Astra, Sweden.  相似文献   
85.
Regional cerebral blood flow was measured with positron emission tomography (PET) in six healthy volunteers at rest and during experimentally induced, sustained cutaneous pain on the dorsum of the right hand or on the dorsum of the right foot. Pain was inflicted by intracutaneous injection of capsaicin, providing a mainly C-fibre nociceptive stimulus. Statistical analysis showed significant activations along the central sulcus (SI) area when comparing pain in the hand to pain in the foot. Separate comparison of both pain states to a baseline revealed different locations along the central sulcus for hand pain and foot pain. The encountered differences are consistent with what is previously known about the somatotopics of non-painful stimuli. When comparing painful stimuli to baseline, the contralateral anterior cingulate gyrus, the ipsilateral anterior insular cortex and the ipsilateral prefrontal cortex were implicated. The results are consistent with an involvement of SI in the spatial discrimination of acute cutaneous pain. Received: 17 October 1996 / Accepted: 12 May 1997  相似文献   
86.
Allergic diseases are characterized by the presence of eosinophils, which are recruited to the affected tissues by chemoattractants produced by T cells, mast cells and epithelium. Our objective was to evaluate if allergens can directly activate human eosinophils. The capacity of purified allergen extracts to elicit eosinophil chemotaxis, respiratory burst, degranulation and up-regulation of the adhesion molecule complement receptor 3 (CR3) was determined in eosinophils isolated from healthy blood donors. Eosinophils stimulated with an extract from house dust mite (HDM) released the granule protein major basic protein (MBP) and up-regulated the surface expression of CR3. Cat allergen extracts also induced the up-regulation of CR3, but not the release of MBP; instead cat, as well as birch and grass allergens, elicited the release of eosinophil peroxidase (EPO). In addition, grass pollen extract caused the secretion of MBP. None of the allergens stimulated eosinophilic cationic protein release, nor production of free oxygen radicals. Both HDM and birch extracts were chemotactic for eosinophils. These findings establish that common aeroallergens can directly activate eosinophils in vitro. We propose that eosinophil activation in vivo is not exclusively mediated by cytokines and chemokines of the allergic inflammatory reaction, but could partly be the result of direct interaction between allergens and eosinophils.  相似文献   
87.
The perforin (PFN) protein is essential for the elimination of target cells by cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. The study of cells releasing PFN has been hampered by a lack of sensitive methods. We therefore produced PFN-reactive monoclonal antibodies (mAb) and developed capture enzyme-linked immunosorbent (ELISA) and enzyme-linked immunospot (ELISpot) assays. Three mAbs were generated and shown to react with unique determinants of PFN. All mAbs recognized intracellular PFN in human peripheral blood mononuclear cell (PBMC) as assessed by flow cytometry and immunohistochemistry. Functional PFN capture ELISA and ELISpot assays were developed utilizing two of the mAbs for capture and the third mAb for detection. When examining PFN release by the YT lymphoma cell line, the ELISpot displayed a greater detection sensitivity than the ELISA. Assessment of PFN release by a CTL clone using ELISpot gave results consistent with a parallel (51)Cr-release cytotoxicity assay. Moreover, PFN release by PBMC could be quantified by ELISpot and ELISA after ex vivo stimulation with defined CTL epitopes from common viruses. These novel immunoassays will be valuable for further investigations of the mechanisms underlying granule-mediated apoptosis. In addition, the capture immunoassays could provide tools for studying CTL responses in infectious and tumor diseases as well as for vaccine development.  相似文献   
88.
Calcitonin gene-related peptide (CGRP) is a novel 37-amino acid peptide occurring in neurones within sensory ganglia, in brain stem, as well as in the walls of blood vessels of peripheral organs. Pial arteries of cat showed a well-developed supply of CGRP-positive nerve fibres. The peptide was found to be a potent dilator of both pial and peripheral vessels of rabbit and cat, and of pial vessels from man. The dilatory effect was independent of the vascular endothelium and was not mediated through adrenergic, cholinergic or histaminergic smooth muscle receptors. The neurogenic vasoconstriction induced by electrical field stimulation was temporarily inhibited by CGRP, as studied in central ear arteries from rabbits. The results suggest that CGRP is a transmitter or modulator playing a role in the regulation of vascular tone.  相似文献   
89.
A common strategy for genotyping large samples begins with the characterization of human single nucleotide polymorphisms (SNPs) by sequencing candidate regions in a small sample for SNP discovery. This is usually followed by typing in a large sample those sites observed to vary in a smaller sample. We present results from a systematic investigation of variation at the human apolipoprotein E locus (APOE), as well as the evaluation of the two-tiered sampling strategy based on these data. We sequenced 5.5 kb spanning the entire APOE genomic region in a core sample of 72 individuals, including 24 each of African-Americans from Jackson, Mississippi; European-Americans from Rochester, Minnesota; and Europeans from North Karelia, Finland. This sequence survey detected 21 SNPs and 1 multiallelic indel, 14 of which had not been previously reported. Alleles varied in relative frequency among the populations, and 10 sites were polymorphic in only a single population sample. Oligonucleotide ligation assays (OLA) were developed for 20 of these sites (omitting the indel and a closely-linked SNP). These were then scored in 2179 individuals sampled from the same three populations (n = 843, 884, and 452, respectively). Relative allele frequencies were generally consistent with estimates from the core sample, although variation was found in some populations in the larger sample at SNPs that were monomorphic in the corresponding smaller core sample. Site variation in the larger samples showed no systematic deviation from Hardy-Weinberg expectation. The large OLA sample clearly showed that variation in many, but not all, of OLA-typed SNPs is significantly correlated with the classical protein-coding variants, implying that there may be important substructure within the classical epsilon 2, epsilon 3, and epsilon 4 alleles. Comparison of the levels and patterns of polymorphism in the core samples with those estimated for the OLA-typed samples shows how nucleotide diversity is underestimated when only a subset of sites are typed and underscores the importance of adequate population sampling at the polymorphism discovery stage. [The sequence data described in this paper have been submitted to the GenBank data library under accession no. AF261279.]  相似文献   
90.
Båth M  Sund P  Månsson LG 《Medical physics》2002,29(10):2286-2297
Two generations of a CCD-based detector system with lens-based optical coupling for digital chest radiography were evaluated in terms of presampling MTF, NPS, NEQ, DQE, linearity in response, and SNR over the detector area. Measurements were performed over a wide exposure range and at several different beam qualities. Neither the presampling MTF nor the DQE showed any general strong beam quality dependence, whereas the NPS and NEQ did when compared at specific entrance air kerma values. The exposure dependency for the DQE was found to be considerable, with the detectors showing low DQE at low exposures, and higher DQE at higher exposures. It was found that the second generation has been substantially improved compared to its predecessor regarding all the relevant parameters. The DQE(0) at an entrance air kerma of 5 microGy increased from 9% to 15%, mainly due to a better system gain (including optical coupling efficiency and matching of the energy of the emitted light photons to the sensitivity of the CCD camera). The first generation of detectors was found to have problems with bad peripheral resolution [MTF(muN/2) <0.1]. This problem was nonexistent for the second generation for which uniform resolution has been obtained [MTF(muN/2)=0.3]. A theoretical calculation of the DQE of two model systems similar to the ones evaluated was also performed, and the results were comparable to the experimentally determined data at high exposures. The model shows that both systems suffer from low optical coupling efficiency due to the large demagnification used. The main conclusion is that although the second generation has been improved, there is still a problem with low system gain leading to relatively modest DQE values, especially at low exposures.  相似文献   
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