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排序方式: 共有370条查询结果,搜索用时 234 毫秒
91.
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
92.
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
93.
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
94.
da Silva VC Ramos FJ Freitas EM de Brito-Marques PR Cavalcanti MN D'Almeida V Cabral-Filho JE Muniz MT 《Arquivos de neuro-psiquiatria》2006,64(4):941-945
OBJECTIVE: To investigate the association between total plasma homocysteine concentration, C677T and A1298C polymorphisms in MTHFR gene and Alzheimer's disease (AD) development. METHOD: Forty-three patients with probable (63%) and possible (37%) AD and 50 non-demented controls were evaluated. Groups did not differ as to gender, age, scholar years, diabetes, alcohol and coffee intake and physical activity. Total plasma homocysteine (Hcy) levels were determined by HPLC and genotyping for MTHFR by PCR/RFLP. Mann-Whitney "U" test was used to compare quantitative variable, Fisher-Freeman-Halton test to compare genotypes and allele proportions and Chi-square test to other qualitative variables. RESULTS: AD patients presented higher total plasma Hcy levels than controls and the difference was statistically significant. No differences in the C677T and A1298C MTHFR polymorphisms distributions were found between patients and controls. Plasma homocysteine concentration did not change with MTHFR genotypes. CONCLUSION: Our data confirms the association between increased plasma Hcy concentration and AD and suggests that neither C677T nor A1298C MTHFR polymorphisms contributed to genetic susceptibility for AD in elderly individuals in the Northeast of Brazil. 相似文献
95.
96.
Marcelo Einicker-Lamas Angelo T. Malaquias Solange L. de Castro Gerry A. Smith Mecia M. Oliveira 《Parasitology research》1999,85(3):232-238
Inositol has been cited as being essential for the growth of micro-organisms and animals. Its action rests mostly in the
formation of a set of inositol-containing lipids, including phosphatidylinositol and its phosphorylated derivatives. To evaluate
the functional responses coupled to the phosphoinositide metabolism in Trypanosoma cruzi we used myo-inositol and its six fluorinated analogues. Their uptake into epimastigotes was characterised using tritium-labeled myo-inositol and monodeoxyfluoro-myo-inositols. The analogues were tested for their ability to inhibit [3H]-myo-inositol incorporation into phosphoinositides and the proliferation of epimastigotes and amastigotes. The results showed
differences between T. cruzi and mammalian systems in the responses to the fluorinated analogues. We found that the 3-, 5- and 6-fluoro analogues did
not enter the cells but had an inhibitory effect on the incorporation of the radioactive inositol into lipids and on the amastigotes'
and epimastigotes' replication. The most effective inhibitor, 1-D-6-deoxy-6-myo-inositol, had no effect on mammalian cell division.
Received: 12 June 1998 / Accepted: 15 September 1998 相似文献
97.
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
98.
99.
100.
Roessler E; Belloni E; Gaudenz K; Vargas F; Scherer SW; Tsui LC; Muenke M 《Human molecular genetics》1997,6(11):1847-1853
Holoprosencephaly (HPE) is the most common brain anomaly in humans,
involving abnormal formation and septation of the developing central
nervous system. Among the heterogeneous causes of HPE, mutations in the
Sonic Hedgehog (SHH) gene have been shown to result in an autosomal
dominant form of the disorder. Here we describe a total of five different
mutations in the processing domain encoded by exon 3 of SHH in familial and
sporadic HPE. This is the first instance in humans where SHH mutations in
the domain responsible for autocatalytic cleavage and cholesterol
modification of the N-terminal signaling domain of the protein have been
observed.
相似文献