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81.
82.
Polymorphonuclear leukocyte heterogeneity in neonates and adults 总被引:1,自引:0,他引:1
Krause PJ; Malech HL; Kristie J; Kosciol CM; Herson VC; Eisenfeld L; Pastuszak WT; Kraus A; Seligmann B 《Blood》1986,68(1):200-204
We have used a mouse monoclonal antibody (31D8) to determine whether differences in neutrophil (PMN) subpopulations might help explain decreased PMN chemotaxis in neonates compared with that of adults. 31D8 has been shown to bind heterogeneously to adult PMNs. Approximately 80% of the PMNs that strongly bind 31D8 (31D8 "bright") are the same cells that depolarize and migrate chemotactically when stimulated with the chemoattractant N-formyl-methionylleucylphenylalanine, while the 20% that weakly bind 31D8 fail to similarly respond. All neonatal PMNs bound 31D8 heterogeneously. There was a smaller population of 31D8 "bright" cells in neonates at birth (76% +/- 6%, n = 45) compared with that of neonates at three to 15 days of age (82% +/- 5%, n = 10, P less than 0.002) and both were smaller than that of adults (88% +/- 4%, n = 45, P less than 0.001 and P less than 0.001). Neonatal cord PMNs, which traversed a micropore filter in a modified Boyden chemotaxis chamber in the presence of a chemoattractant, had an increased percentage of 31D8 "bright" cells (89% +/- 7%) than did PMNs which remained above the filter (82% +/- 7%, n = 10, P = 0.034). PMN chemotaxis was less in neonates at birth (32.7 +/- 4.5 micron) than at three to six days of age (36.8 +/- 11.3 micron) and both were decreased compared with that of adults (69.1 +/- 12.4 micron, P less than 0.001 and P less than 0.001). These findings indicate that decreased PMN chemotaxis in neonates may be due in part to a smaller PMN subpopulation of highly motile cells. 相似文献
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85.
Human marrow erythropoiesis in culture. I. Characterization of methylcellulose colony assay 总被引:11,自引:0,他引:11
We examined the morphological and functional characteristics of human marrow erythrocytes cultured with a recently developed methylcellulose colony assay technique. Erythrocytic cells in various stages of development were observed, and a significant degree of maturational synchrony within individual colonies was noted. By light microscopy, colonies consisting of late normoblasts appeared compact, had an orange hue attributable to their hemoglobin, and demonstrated pseudoperoxidase activity, whereas colonies composed of early erythroblasts grew less compact or in clusters of smaller cell aggregates and showed no reddish tinge. Colonies possessing intermediate features were also observed. Maturational synchrony of individual colonies was confirmed using ransmission and scanning electron microscopy. The ultrastructure and cytochemistry of most immature cells were normal. The mature erythrocytes, however, were severely microcytic and hypochromic and contained one to several Heinz bodies. These defects in the cytoplasmic maturation of erythrocytes corresponded with impaired granulocytic maturation in culture, which we observed previously, and suggest environmental or nutritional defects in culture. Linearity of the method was confirmed using five normal bone marrows. Erythropoietin dose-responses observed in ten normal marrows were comparable to the previously reported results and revealed significant variation in individual plating efficiencies. 相似文献
86.
Kroef MJ; Fibbe WE; Mout R; Jansen RP; Haak HL; Wessels JW; Van Kamp H; Willemze R; Landegent JE 《Blood》1993,81(7):1849-1854
Interstitial deletions of the long arm of chromosome 5 are among the most characteristic abnormalities observed in myeloid disorders. To assess the lineage involvement of peripheral blood cells from patients with a 5q--anomaly, purified neutrophils, monocytes, T lymphocytes, and B lymphocytes were analyzed for loss of heterozygosity using six different highly polymorphic mininucleotide and dinucleotide (CA) repeat sequences from the 5q31 to 5q33 region. Ten patients were screened by polymerase chain reaction (PCR) amplification and proved to be informative for at least one marker. Six patients showed a complete or partial disappearance of an allele in myeloid cells, whereas cells of lymphoid lineages exhibited full heterozygosity. The other patients displayed no allelic loss, indicating that the informative markers were located outside the deleted chromosomal segments. In addition, three female patients who were also polymorphic for the BstXI site in the PGK- 1 gene were analyzed for the methylation status of this gene. Clonality of hematopoiesis, as determined by non-random X-chromosome inactivation, followed the same cell pattern as the 5q-specific allelic losses. In conclusion, using tumor-specific and clonal markers, we have demonstrated that the 5q- anomaly is restricted to cells of myeloid origin, leaving lymphoid cells unaffected. 相似文献
87.
Gene therapy for inherited disorders of blood cells will require both efficient methods for stable gene transfer and nonablative bone marrow conditioning regimens to allow engraftment of modified hematopoietic progenitor cells (HPCs). We have used a sensitive murine system for detecting HPC engraftment using congenic C57BL/6 mice that differ at the Ly5 locus, which encodes the leukocyte common antigen. The system relies on the ability of monoclonal antibodies with specificity for Ly5.1 and Ly5.2 (revised nomenclature: CD45.1 and CD45.2, respectively) to distinguish donor and recipient peripheral blood leukocytes after transplantation of purified Sca-1+ bone marrow-derived HPCs. No detectable engraftment occurred in nonirradiated recipient mice, even when as many as 2.0 x 10(6) SCa-1+HPCs were transplanted. However, in mice receiving total body irradiation (TBI), engraftment increased as a function of pretransplantation radiation dose, number of transplanted cells, and time after transplantation. Moreover, mice receiving either granulocyte colony-stimulating factor (G-CSF) or G-CSF+ stem cell factor before low-dose TBI (160 cGy) exhibited a marked increase in engraftment compared with mice receiving a vehicle control before low- dose TBI (18.9% and 20.6% v 5.6% at a 1 month, respectively; 29% and 35% v 15.1% at 4 months, respectively). Use of growth factor pretreatment even allowed TBI doses as low as 30, 70, or 120 cGy to achieve significant engraftment of donor progenitors (0.3%, 1.5%, and 6.8% at 1 month, respectively; 1.7%, 5.8%, and 13.9% at 4 months, respectively). All animals remained healthy during the observation periods. Thus, growth factor preconditioning of the recipient followed by low-dose TBI may provide an optimal balance between safety and efficacy in achieving required levels of engraftment for gene therapy of blood disorders. 相似文献
88.
构建Loa22基因去信号肽片段原核重组表达载体 总被引:1,自引:0,他引:1
目的:构建赖型钩端螺旋体OmpA膜蛋白Loa22基因去信号肽片段的原核表达载体,并对其进行克隆表达。方法:实验于2004—12/2005—12在四川大学华西医学中心感染免疫研究室完成。以赖型钩端螺旋体017株基因组DNA为模板,PCR扩增Loa22基因去信号肽片段,亚克隆至原核表达载体pGEX-4T-1,经双酶切、PCR鉴定,筛选出阳性重组质粒克隆。经DNA测序正确后,转化大肠杆菌,利用IPTG进行诱导表达,通过SDS—PAGE鉴定表达产物。结果:PCR获得长516bp的片段。Loa22基因去信号肽片段与pGEX-4T-1的重组质粒构建成功。重组质粒经IPTG诱导后能在大肠杆菌中表达Mr45000的融合蛋白。结论:制备了Loa22基因去信号肽片段原核重组表达载体,为钩体新型疫苗的研究奠定基础。 相似文献
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90.
Differentiation of pulmonary parenchymal consolidation from pleural disease using the sonographic fluid bronchogram 总被引:2,自引:0,他引:2
The nature of pleural-based thoracic collections may be sonographically confusing. To help lessen this confusion, the fluid bronchogram, a useful sonographic sign of pulmonary parenchymal consolidation, is described. Bronchi containing fluid in consolidated lung can be identified using ultrasound. 相似文献