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71.

Background  

The New World monkey (Platyrrhini) subfamily Pitheciinae is represented by the genera Pithecia, Chiropotes and Cacajao. In this work we studied the karyotypes of Pithecia irrorata (2n = 48) and Cacajao calvus rubicundus (2n = 45 in males and 2n = 46 in females) by G- and C-banding, NOR staining and chromosome painting using human and Saguinus oedipus whole chromosome probes. The karyotypes of both species were compared with each other and with Chiropotes utahicki (2n = 54) from the literature.  相似文献   
72.
The DNA enzyme Dz13, targeted against the oncogene c-Jun, is capable of inhibiting various model tumours in mice albeit in ectopic models of neoplasia. In previous studies using orthotopic models of disease, the inhibitory effects of Dz13 on secondary growth was a direct result of growth inhibition at the primary lesion site. Thus, the direct and genuine effects on metastasis were not gauged. In this study, Dz13 was able to inhibit both locoregional and distal metastasis of tumour cells in mice, in studies where the primary tumours were unaffected due to the late and clinically-mimicking nature of treatment commencement. In addition, the effect of Dz13 against tumours has now been extended to encompass breast and prostate cancer. Dz13 upregulated the matrix metalloproteinase (MMP)-2 and MMP-9, and decreased expression of MT1-MMP (MMP-14) in cultured tumour cells. However, in sections of ectopic tumours treated with Dz13, both MMP-2 and MMP-9 were downregulated. Thus, not only is Dz13 able to inhibit tumour growth at the primary site, but also able to decrease the ability of neoplastic cells to metastasise. These findings further highlight the growing potential of Dz13 as an antineoplastic agent.  相似文献   
73.
Using a radioimmunoassay specific for the carboxyl terminus of beta-endorphin-(1-9) large amounts of beta-endorphin-(1-9)-immunoreactive material was detected in the human pituitary. The major peak of immunoreactivity was purified and characterized by fast atom bombardment-mass spectrometry and Edman degradation sequencing as authentic beta-endorphin-(1-9). In the rat pituitary the highest concentration of beta-endorphin-(1-9) immunoreactivity was in the posterior neurointermediate lobe. This material was identified as N-acetyl beta-endorphin-(1-9) by multiple radioimmunoassays, gel chromatography, and reversed-phase high-performance liquid chromatography. Control experiments determined that beta-endorphin-(1-9) was not formed postmortem or during the extraction procedure. These studies suggest that single lysine residues, similar to single arginine residues, are potential sites of posttranslational processing.  相似文献   
74.
The mammalian Hippo signaling pathway, through its effectors YAP and TAZ, coerces epithelial progenitor cell expansion for appropriate tissue development or regeneration upon damage. Its ability to drive rapid tissue growth explains why many oncogenic events frequently exploit this pathway to promote cancer phenotypes. Indeed, several tumor types including basal cell carcinoma (BCC) show genetic aberrations in the Hippo (or YAP/TAZ) regulators. Here, we uncover that while YAP is dispensable for homeostatic epidermal regeneration, it is required for BCC development. Our clonal analyses further demonstrate that the few emerging Yap‐null dysplasia have lower fitness and thus are diminished as they progress to invasive BCC. Mechanistically, YAP depletion in BCC tumors leads to effective impairment of the JNK‐JUN signaling, a well‐established tumor‐driving cascade. Importantly, in this context, YAP does not influence canonical Wnt or Hedgehog signaling. Overall, we reveal Hippo signaling as an independent promoter of BCC pathogenesis and thereby a viable target for drug‐resistant BCC.  相似文献   
75.
The phytopathogenic fungus Cochliobolus carbonum produces an extracellular enzyme capable of degrading beta 1,3-glucan in an exolytic manner. On the basis of partial amino acid sequences of the purified enzyme, two degenerate oligonucleotides were synthesized and used as PCR primers to amplify a 1.1-kb fragment of corresponding genomic DNA. The PCR product was used to isolate the genomic copy of the gene, called EXG1. Partial sequencing of the genomic DNA confirmed that the PCR product corresponded to EXG1. A strain of the fungus specifically mutated in the EXG1 gene was constructed by homologous integration of an internal fragment of EXG1. In the mutant, enzymatic activity and the corresponding peak of UV absorption during high-pressure liquid chromatography purification were reduced by at least 98%. However, crude culture filtrates of the mutant retained 44% of the wild-type beta 1,3-glucanase activity. This residual activity was due to two additional activities which were chromatographically separable from the product of EXG1 and which were coeluted with beta 1,3-beta 1,4-glucanase activity. Growth of the EXG1 mutant was normal on sucrose and oat bran but was reduced by 65% on pure beta 1,3-glucan. The EXG1 mutant was still pathogenic to maize.  相似文献   
76.
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