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Successful complete hematopoietic reconstitution (CHR) using nonleukemic peripheral stem cells (PSC) after marrow ablation has been reported in animals but not man. Previous studies of cytapheresis products from humans, as a prelude to use for CHR, have documented the presence of committed myeloid (CFU-GM) and erythroid (BFU-E) precursors. We have examined mononuclear cell (MNC) products collected on the Fenwal CS3000 Blood Cell Separator for these plus the more primitive mixed (granulo-, erythro-, mono-, and megakaryocytic) cell colony-forming units (CFU-GEMM) and for various lymphocytic subpopulations (LSP). One to two-hour products contained 36 +/- 7 CFU- GEMM/10(6) MNC (mean +/- SE, n = 8) or 490 +/- 131/ml product. This compared favorably with blood (23 +/- .4/10(6) MNC or 46 +/- 8/ml, n = 14) and bone marrow (146 +/- 58/10(6) MNC, n = 12). Collection efficiency for E-rosette-positive cells approximated that for total lymphocytes and was variable for other LSP. Recovery of CFU-GEMM after freezing in 10% dimethylsulfoxide at a controlled rate and storage in liquid N2 was 54% +/- 8% (n = 8). Cytapheresis collection of large numbers of pluripotent hematopoietic precursors and demonstration of adequate recovery of these after cryopreservation, both previously unreported, are significant steps toward eventual CHR using nonleukemic PSC. 相似文献
75.
A case of lymphoid blast crisis of Ph1-positive CGL is described in which the blast cells had an immature T cell phenotype, clonal rearrangement and expression of the T cell receptor beta gene, and a rearrangement of the breakpoint cluster region (bcr) on chromosome 22. This case therefore provides definite evidence for transformation involving a common myeloid-T lineage progenitor, penetrance of the Ph1 molecular alteration into the T cell lineage, and clonal selection in blast crisis at the level of a committed T lineage precursor. 相似文献
76.
Sturk A; Schaap MC; Prins A; ten Cate JW; Govaerts LC; Wanders RJ; Heymans HS; Schutgens RB 《Blood》1987,70(2):460-463
Ca2+-ionophore A23187-induced synthesis of the alkoxyether lipid platelet activating factor (PAF) by leukocytes from Zellweger patients was undetectable in two patients studied at 3 and 4 weeks of age, reduced in a third patient studied at 2 months of age, and in the low normal range in four patients studied between 4 months and 5 years of age. We have previously reported that plasmalogen-type phosphatidylethanolamine (PE) levels of erythrocytes are reduced in Zellweger patients up to 20 weeks of age, but normal in older patients. These levels were reduced in the three patients with abnormal PAF synthesis, and normal in the other four patients. The results suggest a close relationship between the age of the patients at sampling, and both the A23187-induced capacity of leukocytes to synthesize PAF and the plasmalogen PE levels in their erythrocytes. 相似文献
77.
Establishment of two new myeloma cell lines from bilateral pleural effusions: evidence for sequential in vivo clonal change 总被引:3,自引:0,他引:3
Durie BG; Vela E; Baum V; Leibovitz A; Payne CM; Richter LC; Grogan TM; Trent JM 《Blood》1985,66(3):548-555
Two new human myeloma cell lines have been established from a 36-year- old woman with refractory IgG kappa multiple myeloma in whom bilateral malignant pleural effusions developed. The malignant plasma cells from each effusion were set up in a liquid culture using an L-15 medium containing catalase, glutathione, selenous acid, ascorbic acid, insulin, transferrin, additional glutamine hydrocortisone, and 2- mercaptoethanol and designated as M-3 medium. Two IgG kappa cell lines, LB -831 and LB-832, were established and proved to be Epstein-Barr virus negative using the internal repeat sequence DNA probe. Characteristic plasma cell morphology was evident by light and electron microscopy. Immunotyping revealed an IgG kappa , B1+, B2-, Ia (HLA- DR)+, CALLA+ phenotype for each cell line as well as for the original pleural fluid and bone marrow myeloma cells. The supernatants also contained IgG kappa, beta 2 microglobulin, and large amounts of osteoclast-activating factor (indicating bone-resorbing activity). Cytogenetic analysis of the LB-831 cell line revealed a nearly triploid highly abnormal karyotype with numerous clonal chromosomal abnormalities involving chromosomes 1, 3, 5, 7, 13, and 15; several structurally abnormal marker chromosomes; and a putative homogeneously staining region on chromosome 7p at band p22. Analysis of the LB-832 cell line revealed several additional clonal abnormalities. These additional cytogenetic changes suggest that in vivo sequential clonal evolution occurred in this patient. Therefore, two new but related cell lines have been established, which should prove useful for further biological studies. 相似文献
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RL HENRY LC HETTIARACHCHI P COLLEY C COLLLINS EV O'LOUGHLIN DM COOPER 《Journal of paediatrics and child health》1996,32(5):416-418
Objective : To determine the genotype of patients attending the cystic fibrosis clinic at John Hunter Hospital, Newcastle, Australia.
Methodology : Seventy-five of the 76 patients attending the clinic over a 6 month period had blood collected for genetic analysis of 17 of the cystic fibrosis (CF) gene mutations.
Results : Sixty-one per cent of the patients were homozygous for the ΔF508 mutation and all except one child had at least one ΔF508 mutation.
Discussion : Nearly 80% of the CF genes were the ΔF508 mutation. This prevalence suggests that the obligatory false negative rate of a newborn screening programme for CF based on a combination of immunoreactive trypsin and the ΔF508 gene may be as low as 4-5%. 相似文献
Methodology : Seventy-five of the 76 patients attending the clinic over a 6 month period had blood collected for genetic analysis of 17 of the cystic fibrosis (CF) gene mutations.
Results : Sixty-one per cent of the patients were homozygous for the ΔF508 mutation and all except one child had at least one ΔF508 mutation.
Discussion : Nearly 80% of the CF genes were the ΔF508 mutation. This prevalence suggests that the obligatory false negative rate of a newborn screening programme for CF based on a combination of immunoreactive trypsin and the ΔF508 gene may be as low as 4-5%. 相似文献
80.
JC?CohenEmail author M?Gyansa-Lutterodt K?Torpey LC?Esmail G?Kurokawa 《Globalization and health》2005,1(1):17
There are acute disparities in pharmaceutical access between developing and industrialized countries. Developing countries
make up approximately 80% of the world's population but only represent approximately 20% of global pharmaceutical consumption.
Among the many barriers to drug access are the potential consequences of the Trade Related Aspects of Intellectual Property
Rights (TRIPS) Agreement. Many developing countries have recently modified their patent laws to conform to the TRIPS standards,
given the 2005 deadline for developing countries. Safeguards to protect public health have been incorporated into the TRIPS
Agreement; however, in practice governments may be reluctant to exercise such rights given concern about the international
trade and political ramifications. The Doha Declaration and the recent Decision on the Implementation of Paragraph 6 of the
Doha Declaration on the TRIPS Agreement and Public Health may provide more freedom for developing countries in using these
safeguards. This paper focuses on Ghana, a developing country that recently changed its patent laws to conform to TRIPS standards.
We examine Ghana's patent law changes in the context of the Doha Declaration and assess their meaning for access to drugs
of its population. We discuss new and existing barriers, as well as possible solutions, to provide policy-makers with lessons
learned from the Ghanaian experience. 相似文献