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Comparison of immune electron microscopy and genome electropherotyping techniques for detection of turkey rotaviruses and rotaviruslike viruses in intestinal contents. 总被引:3,自引:3,他引:0 下载免费PDF全文
Seventy-nine intestinal contents specimens from 65 turkey flocks were examined for rotavirus and rotaviruslike virus (RVLV) by immune electron microscopy (IEM) and genome electropherotyping. The IEM procedure was slightly more sensitive in detecting these viruses; 7 of 48 specimens (14.6%) positive for virus by IEM were negative by the genome electropherotyping technique. The genome electropherotyping technique more readily differentiated the rotaviruses and RVLVs than did the IEM procedure; 15 of 48 specimens (31%) positive for virus by IEM could not be differentiated into rotavirus of RVLV, whereas only 4 of the 41 specimens (9.7%) positive by genome electropherotyping produced incomplete genome electropherotypes and could not be differentiated. Thirty-one specimens negative by IEM were also negative by genome electropherotyping. Specimens determined to contain only rotavirus by IEM produced only rotavirus genome electropherotypes. Likewise, specimens determined to contain RVLV alone by IEM produced only RVLV genome electropherotypes. Three specimens contained viruses morphologically resembling rotaviruses that were not aggregated by either the anti-turkey rotavirus serum or the anti-turkey RVLV serum and possessed genome electropherotypes distinct from those of the turkey rotavirus and RVLV. These rotaviruses may represent a third, previously unrecognized serogroup of turkey rotaviruses. 相似文献
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Development of cDNA probes for typing group A bovine rotaviruses on the basis of VP4 specificity. 下载免费PDF全文
Dot and Northern (RNA) blot hybridization assays were developed for the P typing of group A bovine rotaviruses (BRV) by using cDNA probes prepared from gene segment 4. The probes were prepared by polymerase chain reaction amplification of hyperdivergent regions (nucleotides 211 to 686) of BRV strain UK, IND, NCDV, and Cr VP4 cDNA by using specific oligonucleotide primers. The probes were P type specific (VP4) and exhibited little or no cross-reactivity with double-stranded RNA from heterologous rotavirus P types. Our studies indicate that at least three P types, as defined by polymerase chain reaction-derived VP4 gene probes from the UK, NCDV, and Cr strains, exist among the seven BRV isolates tested. 相似文献
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Totally extra-peritoneal (TEP) laparoscopic repair of an inguinalhernia involves the creation of an extra-peritoneal space by blunt dissection or the use of commercial balloons. This new technique demonstrates the use of a device to create this extra-peritoneal space, without the need for any commercial balloons. The extra-peritoneal space was created using a glove-balloon. A total of 107 consecutive TEP repairs were carried out using the glove-balloon technique, these included ten bilateral and 17 recurrent inguinal hernias. This method is simple, cost-effective and easy to teach. 相似文献
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Summary. Bovine coronavirus (BCV) causes neonatal calf diarrhea (CD) and is associated with winter dysentery (WD) in adult dairy cattle.
It can also be isolated from the respiratory tracts of cattle entering feedlots. Monoclonal antibodies (MAbs) specific for
the hemagglutinin esterase (HE) and spike (S) surface proteins of 2 bovine enteric coronavirus (BECV) strains and two bovine
respiratory coronavirus (BRCV) strains were tested against 6 BECV strains and 6 recently isolated BRCV strains, in order to
characterize the antigenicity of BCV strains with varied tissue tropisms. All MAbs had high immunofluorescence (IF) titers
against BECV and BRCV strains, indicative of conserved cross-reactive epitopes. In hemagglutination inhibition (HI) tests,
the S-MAbs were more broadly reactive than HE-MAbs. The BRCV and CD MAbs were more broadly reactive in HI than the WD MAbs.
The HA activity of the Mebus vaccine CD strain was not inhibited by any of the MAbs tested. The HI activity of BRCV strain
R6 was unique among the 6 BRCV isolates. In virus neutralization assays, MAbs to the BRCV strain R4 neutralized all 6 BECV
strains tested. Antigenic variation exists among both BECV and BRCV strains, but it cannot be attributed soley to the clinical
origin of the strain.
Received February 9, 1998/Accepted July 22, 1999 相似文献
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B. M. Jiang H. Tsunemitsu Y. Qian K. Y. Green M. Oseto Y. Yamashita Linda J. Saif 《Archives of virology》1992,126(1-4):45-56
Summary Two partial cDNA clones of genes 5 (encoding the major inner capsid protein VP 6) and 6 (encoding a nonstructural protein) of the porcine group (Gp) C rotavirus (Cowden strain) were radiolabeled with32P and used individually as probes in Northern and dot blot hybridization assays. The specificity of each probe was tested against genomic dsRNA from: (1) porcine Gp A, B, and C rotaviruses; (2) Gp C rotaviruses from different species; and (3) porcine Gp C rotavirus field strains with varying electropherotype patterns. Neither probe hybridized with ds RNA from the porcine Gp A and B strains under the stringency conditions employed in the study. However, the gene 5 probe hybridized with the corresponding gene from the homologous porcine and the heterologous human and bovine Gp C rotaviruses tested. The gene 6 probe hybridized with the corresponding gene from the homologous Cowden strain, but hybridized weakly with gene 6 from the human and bovine Gp C rotaviruses. Both probes recognized all six different porcine Gp C field strains, although with varying intensities. Our results demonstrate that the gene 5 and 6 probes used in this study are specific for Gp C rotaviruses. However, evidence for greater genetic variation in the gene 6 among porcine, bovine and human Gp C strains suggested that the gene 5 probe may prove more broadly reactive among Gp C strains from different species. cDNA probes used in our study should prove useful for the detection of Gp C rotaviruses in feces and facilitate epidemiologic studies. 相似文献
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A sample of 1150 unemployed 17 year-olds, containing blacks and whites, males and females, was obtained from 11 urban regions in England. Social support was measured in respect of five different forms of help from others. Measures were also obtained of psychological distress, perceived pressure from others to obtain a job, employment commitment, contact with other young people, and contact with other unemployed young people. Two forms of social support (having someone to turn to for help with money, and having someone to suggest interesting things to do) were significantly associated with measures of distress, as were perceived pressure to obtain a job and employment commitment, but not contact with other unemployed young people. The association between distress and having someone to turn to for help with money was greater for those perceiving pressure from others to obtain a job than those not perceiving pressure. Also, the association between distress and having someone to turn to when feeling low was greater for those with a high employment commitment than for those with a low one. Other associations between support and distress were found to be affected by sex and ethnic differences in the sample. The results are discussed in the light of a stress-buffering model of social support; and the need to disaggregate social support into its component parts is emphasized. 相似文献