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Among the prepared novel cephalosporin derivatives related to S-3578, a series of 7beta-[2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-ethoxyiminoacetamido]-3-[1-(aminoalkyl)-1H-pyrazolo[4,3-b]pyridinium-4-yl]methyl-3-cephem-4-carboxylate showed potent activity against both MRSA and Pseudomonas aeruginosa, and displayed good water solubility.  相似文献   
23.
Traumatic Brain Injury (TBI) is the result of a mechanical impact on the brain provoking mild, moderate or severe symptoms. It is acknowledged that TBI leads to apoptotic and necrotic cell death; however, the exact mechanism by which brain trauma leads to neural injury is not fully elucidated. Some studies have highlighted the pivotal role of the Kallikrein-Kinin System (KKS) in brain trauma but the results are still controversial and inconclusive. In this study, we investigated both the expression and the role of Bradykinin 1 and 2 receptors (B1R and B2R), in mediating neuronal injury under chemical neurotoxicity paradigm in PC12 cell lines. The neuronal cell line PC12 was treated with the apoptotic drug Staurosporine (STS) to induce cell death. Intracellular calcium release was evaluated by Fluo 4-AM staining and showed that inhibition of the B2R prevented calcium release following STS treatment. Differential analyses utilizing immunofluorescence, Western blot and Real-time Polymerase Chain Reaction revealed an upregulation of both bradykinin receptors occurring at 3h and 12h post-STS treatment, but with a higher induction of B2R compared to B1R. This implies that STS-mediated apoptosis in PC12 cells is mainly conducted through B2R and partly via B1R. Finally, a neuroproteomics approach was conducted to find relevant proteins associated to STS and KKS in PC12 cells. Neuroproteomics results confirmed the presence of an inflammatory response leading to cell death during apoptosis-mediated STS treatment; however, a “survival” capacity was shown following inhibition of B2R coupled with STS treatment. Our data suggest that B2R is a key player in the inflammatory pathway following STS-mediated apoptosis in PC12 cells and its inhibition may represent a potential therapeutic tool in TBI.  相似文献   
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Chili pepper is one of the main crops of economic importance in Mexico, and Fusarium wilting is a disease that limits its production. In addition, the inappropriate use of agrochemicals in farming activities generate environmental and health problems. Therefore, in this study the effectiveness of Streptomyces sp PRIO41 was evaluated as a (1) biocontrol agent of Fusarium spp and (2) plant growth promoter bacteria. Assays of pathogenicity and virulence of Fusarium spp. in jalapeño pepper seeds, and interactions of these pathogens with Streptomyces PRIO41 were evaluated under two nutritional conditions. In the greenhouse, the effectiveness of Streptomyces sp. PRIO41 was determined as a (1) biocontrol of Fusarium, and (2) plant growth promoter of wilt of pepper plants. The results showed that all fungal isolates caused symptoms in pepper seeds and seedlings with different degrees of virulence. Interactions in vitro showed that Streptomyces showed the most effective range of virulence against Fusarium isolates in the poor medium (37.6%-100%), with fungicidal effects in some cases. In the greenhouse, Streptomyces PRIO41 reduced Fusarium wilting up to a 40%, and positively affected all vegetative growth parameters, particularly plant height, leaf area, root length, and leaf and root dry biomasses. This study showed the potential of Streptomyces PRIO41 as a biocontrol agent of Fusarium spp., and as a biofertilizer of pepper plants.  相似文献   
26.
We have recently cloned a plasmid, pARS65, containing the sequences derived from mouse liver DNA which can autonomously replicate in mouse and human cells (Ariga et al., 1987). In this report, we show that replication of pARS65 in HL-60 cells can be inhibited by co-transfection with anti-c-myc antibody. In an in-vitro replication system using HL-60 nuclear extract, pARS65 functioned as a template. This in-vitro replication was also blocked by addition of anti-c-myc antibody. Specific binding activity of the c-myc product to pARS65 was detected by an immunobinding assay, suggesting that the c-myc protein promotes DNA replication through binding to the initiation site of replication. This has been substantiated using the antibody to help isolate a human DNA segment that can autonomously replicate in the cells.  相似文献   
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We have already reported that the cloned mouse DNA fragment (pMU65) could replicate in a simian virus 40 T antigen-dependent system in vivo and in vitro (H. Ariga, Z. Tsuchihashi, M. Naruto, and M. Yamada, Mol. Cell. Biol. 5:563-568, 1985). The plasmid p65-tk, containing the thymidine kinase (tk) gene of herpes simplex virus and the BglII-EcoRI region of pMU65 homologous to the simian virus 40 origin of DNA replication, was constructed. The p65-tk persisted episomally in tk+ transformants after the transfection of p65-tk into mouse FM3Atk- cells. The copy numbers of p65-tk in FM3Atk+ cells were 100 to 200 copies per cell. Furthermore, the p65-tk replicated semiconservatively, and the initiation of DNA replication started from the mouse DNA sequences when the replicating activity of p65-tk was tested in the in vitro DNA replication system developed from the FM3A cells. These results show that a 2.5-kilobase fragment of mouse DNA contains the autonomously replicating sequences.  相似文献   
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In the Japanese newspaper industry, since the late 1970s, computerization has been started in large scale. The system, called Computerized Typesetting System (CTS), has been introduced. With this system, all information in the newspaper is input into a computer, called up on a cathode ray display (CRT) to edit, and then output to film or printing plates by CTS. Thus, the work of newspaper production has undergone a major transformation from industrial work to clerical work. It was reported that newspaper production staff working with VDTs complained more than staff working with the older key system about visual and physical problems which affected their job and their daily life. The complaint rates were highest for editors, who used VDT constantly throughout the day. This study was performed to clarify the health impact of VDT use and to prevent health disorders caused by the introduction of CTS. It is concluded that 5 m corrected vision and sphere refraction of CTS workers who used CTS over 2 or 4 hr daily, significantly became worse in a year after the introduction. Therefore, it is indicated that the control of CTS work time is important to prevent the visual disorder.  相似文献   
30.
As a part of our continuing research on NPY-Y5 receptor antagonists in the series of novel 6-methoxybenzo[a]cycloheptene derivatives, we discovered a novel skeleton, 7-methoxy-1-hydroxytetraline 7 which had been used as an intermediate, to be more suitable for increasing potencies leading to compound 3 (FR230481). Additionally, we discovered that the naphthalenesulfonamide moiety which was thought to be an essential pharmacophore could be replaced by the 5-chlorobenzothiazolin-3-acetic acid moiety to lead to potent compound 4 (FR233118). The structure-activity relationships on compounds 3,4 and their related derivatives are described. Unfortunately, although compounds 3 and 4 had very high affinities for Y5 receptors, their poor permeabilities to brain were shown by exo-vivo binding assays when orally administered.  相似文献   
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