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排序方式: 共有4926条查询结果,搜索用时 11 毫秒
21.
We studied 11 cases of malignant lymphoma diagnosed concurrently with or following lymph node infarction. Cases included seven B-cell lymphomas, three T-cell lymphomas, and one case of Hodgkin's disease. Sections of viable and infarcted tissue were immunostained in parallel using a panel of antibodies effective in routinely processed, wax-embedded tissue. The panel included anti-leucocyte-common antigen (CD45), T-cell-associated antigens (UCHL1, MT1), B-cell-associated antigens (MB1, 4KB5 (CD45R), MT2, LN1), a B-cell-specific antigen (L26), C3D-1 (CD15), and BER-H2 (CD30). Antibodies to intermediate filament cytoskeletal proteins, epithelial membrane antigen, and Factor VIII-related antigen were also used. In eight cases, staining of the infarcted material gave evidence of a lymphoid proliferation of either T- or B-cell type; an in the case of Hodgkin's disease, the results supported this diagnosis. The immunophenotype derived in the infarcted tissue mirrored the findings in the viable material in these eight cases of non-Hodgkin's lymphoma. A case of testicular infarction with concurrent intraosseous lymphoma was also examined. Staining in this case provided evidence of infarcted lymphoma. Thus, immunostaining of infarcted lymphoid tissue with these novel antibodies provides valuable information that conventional light microscopy cannot offer. 相似文献
22.
We hypothesize that pulsed electromagnetic fields (PEMF) alter phenotypic expression of chondroblasts by promoting the production of alkaline phosphatase (AP) and altering the structure of proteoglycans. Chondroblasts from the hypertrophic zone of tibial epiphyses (HC), sternum (SC), and skin fibroblasts (F) were cultured from 16 day chick embryos. Cultures were randomly designated control (C) or experimental (E). E received PEMF for 24 h in a 6 h on, 6 h rest sequence. The controls were in the same incubator shielded by Mu metal. Assays for AP activity were performed and normalized to protein content. Proteoglycan synthesis assay involved labeling with 35S fractionating in a 5% to 20% surcrose gradient determining total protein and chondroitin sulfate content. PEMF showed no change of AP activity on F. A high AP basal activity was found in HC, but was not increased above the control. PEMF increased AP in the SC samples (E/C ratio). The sucrose gradient data showed a shift in peaks for SC only altering the ratio of carbohydrate to protein for the SC. Analysis of carbohydrate and protein indicated that the effect was decreased synthesis or degradation of protein. We conclude that PEMF alters the phenotypic expression of sternal chondroblasts in our in vitro system. 相似文献
23.
We tested the hypothesis that electric perturbation influences 45Ca incorporation in extracellular matrix (ECM) of cartilage in vitro. Hypertrophic chondroblasts of tibial epiphyses (HC), sternum (SC), and skin fibroblasts (F) were cultured from chick embryos. HC, SC, and F cells were micromass seeded three times per week and maintained at 37.5 degrees C with 5% CO2 for two weeks. Cultures were randomly designated control (C) or exposed (E) to a pulsed electromagnetic field (PEMF). A time course experiment of calcium incorporation for all cultured groups showed that 24 h of exposure produced the largest biological response in chondroblasts. Calcium incorporation required supplemental phosphate. Autoradiography data indicated that the calcium incorporation into macromolecules largely occurred in the ECM. 45Ca steady-state perturbation was enhanced by Streptomyces hyaluronidase (SH) but not by testicular hyaluronidase (TH). 45Ca incorporation experiments tested the effects of phosphate, SH, TH, and PEMF alone and in various combinations on these cultures. Only PEMF or SH plus PEMF with phosphate enhanced 45Ca incorporation. Other experiments examined the effect of rotenone or freeze-thawing on cells exposed to PEMF. PEMF plus freeze-thaw enhanced calcium incorporation in HC only. PEMF appeared to cause disruption of the ECM, enhancing the probability of matrix calcification. 相似文献
24.
J A Maldjian K I Norton G M Groisman P M Som 《AJNR. American journal of neuroradiology》1994,15(4):784
Inflammatory pseudotumor is a benign neoplasm composed of fibroblasts, histiocytes, and inflammatory cells. Its occurrence in the paranasal sinuses is rare. We report a case of a 15-year-old boy with a maxillary sinus inflammatory pseudotumor that simulated an aggressive neoplasm on CT scan. 相似文献
25.
A randomized, prospective trial of postoperative somatostatin analogue in patients with neuroendocrine tumors of the pancreas. 总被引:4,自引:0,他引:4
J R Lange S M Steinberg G M Doherty H N Langstein D E White T H Shawker R C Eastman R T Jensen J A Norton 《Surgery》1992,112(6):1033-7; discussion 1037-8
BACKGROUND. Pancreatic surgery is not uncommonly complicated by prolonged pancreatic drainage and fistula. Octreotide decreases pancreatic exocrine function and has been reported to improve closure of pancreatic and intestinal fistulae. This randomized, prospective trial was designed to evaluate the efficacy of postoperative octreotide in reducing pancreatic drainage and complications after resection of neuroendocrine tumors of the pancreas. METHODS. Patients with neuroendocrine tumors of the pancreas were entered into the study and randomized after operation to receive octreotide 150 micrograms subcutaneously every 8 hours or saline solution subcutaneously every 8 hours in a double-blinded fashion. Daily pancreatic drainage, total drainage, number of days to drain removal, and complications were recorded. RESULTS. Ten patients were given octreotide; eleven patients were given saline solution. The number of days to drain removal, daily drainage, and total drainage were not significantly different. Complications related to pancreatic drainage were not significantly different. CONCLUSIONS. Octreotide is not indicated for the routine postoperative management of patients with neuroendocrine tumors of the pancreas. 相似文献
26.
Localization and resection of insulinomas and gastrinomas 总被引:2,自引:0,他引:2
27.
The chemical, physical and biological properties of the cytolysin tenebrosin-C from Actinia tenebrosa have been compared with those of equinatoxin II from Actinia equina. The two proteins are indistinguishable by reverse-phase and cation-exchange HPLC and capillary zone electrophoresis, and give similar peptide fragments upon cyanogen bromide cleavage (as judged by the chromatographic behaviour, ultraviolet absorption spectra, amino acid composition and N-terminal amino acid sequences of the peptides). Their cardiac stimulatory activities are identical, and their haemolytic activities are similar, with equinatoxin II having slightly greater activity. These data indicate that the two molecules are either identical in all 179 amino acid positions, or differ by no more than one or two residues. These findings are discussed in the context of the taxonomic relationship between the two species of sea anemone. 相似文献
28.
Gangliosides of cultured astroglia 总被引:3,自引:0,他引:3
Michele Sbaschnig-Agler Henri Dreyfus William T. Norton Monique Sensenbrenner Muhammad Farooq Mary C. Byrne Robert W. Ledeen 《Brain research》1988,461(1):98-106
Cultured astrocytes prepared from newborn rat brain and 13-day-old chick embryonic brain were analyzed qualitatively and quantitatively for ganglioside content. All preparations contained approximately the same total level: 2.4-3.4 micrograms N-acetylneuraminic acid (NeuAc)/mg protein. In contrast, the value for primary cultures of neurons from chick embryonic brain was 5.9. The non-hexosamine-containing species, GM3 and GD3, comprised 75-85% of the total in astroglial cultures, the remainder consisting mainly of structural types other than the gangliotetraose series; choleragenoid assay revealed the latter to be virtually absent or to comprise at most a few percent. Deficiency of gangliotetraose synthesizing ability was indicated by the very low level of UDP-GalNac:GM3 N-acetylgalactosaminyltransferase detected in the cells. Treatment of cultured astrocytes with astroglial growth factor 2 or dibutyryl cyclic AMP caused little if any change in quantity or pattern of gangliosides. The large majority of cells stained in a manner characteristic of astrocytes: positive for glial fibrillary acidic protein, negative for galactosyl ceramides. Staining with cholera toxin and anti-GM1 antibody was essentially negative, as was that with tetanus toxin, A2B5 monoclonal antibody, and antibody to GD3. All evidence thus points to cultured astrocytes of rat and chick brain containing appreciable gangliosides, most of which are GM3 and GD3 with the majority of the remainder comprising structures other than the gangliotetraose type. 相似文献
29.
Crystal deposits in the human intervertebral disc: implications for disc degeneration. 总被引:1,自引:0,他引:1
BACKGROUND CONTEXT: Although crystal deposition in cartilage and synovial fluid has received much attention, crystal formation and the role that crystal deposits play are virtually unexplored in the intervertebral disc. In articular cartilage matrix, crystal deposits are associated with altered extracellular matrix (ECM) and cell phenotypic features, but crystal deposition in the human intervertebral disc has received much less attention. PURPOSE: To determine the incidence of crystal deposits in the annulus and to evaluate associated disc cell and ECM features. STUDY DESIGN/SETTING: Human intervertebral disc annulus tissue was obtained in a prospective study of the presence of crystals in the disc ECM. Human Subjects Institutional Review Board approved experimental studies. PATIENT SAMPLE: Two hundred eight sequential disc specimens were submitted from surgical disc procedures performed on individuals with herniated discs, degenerative disc disease, or recurrent disc herniation. During this same time period, three disc specimens were received from nonsurgical donors and added to the study population. OUTCOME MEASURES: Histologic features with special attention to crystal deposition. METHODS: Specimens were processed undecalcified and examined for the histologic presence of crystal deposits and ECM features around the crystals. RESULTS: The proportion of specimens containing crystals was determined to be 14.7%; crystals displayed varying sizes, morphology, and polarized light birefringence features. Pyrophosphate crystals were most common, but oxalate-like crystals were also present. ECM in crystal regions showed previously recognized alterations. CONCLUSIONS: This study shows that the incidence of crystal deposits in discs is approximately 15% and is thus a relatively common occurrence. These data are important because masses of crystals not only disrupt disc ECM but may also accelerate preexisting degenerative changes via an elevation in matrix metalloproteinases (as previously recognized in cartilage). Because failure of the structural integrity of the disc can result in annular tears and subsequent disc herniation, the mechanisms of crystal formation and the relationship between crystals and disc degeneration merit further investigations. 相似文献
30.