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41.
Summary A new species and a new variety ofSpirogyra have been recorded.Spirogyra varshaii spec. nov. has been described and compared to two related species ofSpirogyra. This species has a very distinct subdenticulate to denticulate type of ornamentation of the zygospore wall and differs from the other two related speciesS. chakiense andS. verruculosa in having different dimensions of the zygospores and in the number of chloroplasts. A new variety,Spirogyra chakiense var.lucknowense var. nov. has been described. It differs from the speciesS. chakiense in possessing some differences in the dimensions of the cells and the zygospores from the type species.
Zusammenfassung Eine neue Spezies und eine neue ArtSpirogyra sind eingetragen worden.Spirogyra varshaii Spec. nov. ist beschrieben worden und mit zwei verwandten Spezies verglichen. Diese Spezies hat einen sehr deutlichen unterzahnigen bis zum zahnigen Typus der gestickten Zygosporeswand, und sie unterscheidet sich von den anderen zwei verwandten SpeziesS. chakiense undS. verruculosa daß sie verschiedene Ausdehnungen der Zygosporen und auch eine verschiedene Zahl der Kromatophoren hat. Eine neue ArtSpirogyra chakiense var.lucknowense var. nov. ist auch beschrieben worden. Sie unterscheidet sich von der SpeziesS. chakiense weil sie einigen Unterschieden in Ausdehnungen der Zellen und auch der Zygosporen hat im Vergleich mit der Typusspezies.
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42.
Interaction of Pyk2 and PTP-PEST with leupaxin in prostate cancer cells   总被引:1,自引:0,他引:1  
We have identified the presence of leupaxin (LPXN), which belongs to the paxillin extended family of focal adhesion-associated adaptor proteins, in prostate cancer cells. Previous studies have demonstrated that LPXN is a component of the podosomal signaling complex found in osteoclasts, where LPXN was found to associate with the protein tyrosine kinases Pyk2 and c-Src and the cytosolic protein tyrosine phosphatase-proline-, glutamate-, serine-, and threonine-rich sequence (PTP-PEST). In the current study, LPXN was detectable as a 50-kDa protein in PC-3 cells, a bone-derived metastatic prostate cancer cell line. In PC-3 cells, LPXN was also found to associate with Pyk2, c-Src, and PTP-PEST. A siRNA-mediated inhibition of LPXN resulted in decreased in vitro PC-3 cell migration. A recombinant adenoviral-mediated overexpression of LPXN resulted in an increased association of Pyk2 with LPXN, whereas a similar adenoviral-mediated overexpression of PTP-PEST resulted in decreased association of Pyk2 and c-Src with LPXN. The overexpression of LPXN in PC-3 cells resulted in increased migration, as assessed by in vitro Transwell migration assays. On the contrary, the overexpression of PTP-PEST in PC-3 cells resulted in decreased migration. The overexpression of LPXN resulted in increased activity of Rho GTPase, which was decreased in PTP-PEST-overexpressing cells. The increase in Rho GTPase activity following overexpression of LPXN was inhibited in the presence of Y27632, a selective inhibitor of Rho GTPase. In conclusion, our data demonstrate that LPXN forms a signaling complex with Pyk2, c-Src, and PTP-PEST to regulate migration of prostate cancer cells. PC-3; protein tyrosine phosphatase-proline-, glutamate-, serine-, and threonine-rich sequence; c-Src; migration  相似文献   
43.
The macrophage protein tyrosine phosphatase-1 SHP-1 has been implicated in the pathogenesis of infection with leishmania. To identify the factors that may interact with SHP-1, Leishmania donovani promastigote lysates were added to a GST-SHP-1 affinity matrix. A 44 kDa specifically bound protein was identified as leishmania fructose-1,6-bisphosphate aldolase (aldolase). Purified leishmania aldolase bound to SHP-1 indicating that the interaction was direct. In contrast, purified mammalian aldolase did not bind to SHP-1. Consistent with this, leishmania aldolase activated SHP-1 in vitro, whereas mammalian aldolase did not. The presence of leishmania aldolase in the cytosolic fractions prepared from infected macrophages indicated that leishmania aldolase is exported from phagolysosomes in infected cells where it can target host cytosolic proteins. In fact, co-immunoprecipitation showed association of leishmania aldolase with SHP-1. Moreover, leishmania aldolase-expressing macrophages showed the deactivated phenotype of leishmania infected cells as judged by much reduced inability to induce expression of nitric-oxide synthase in response to interferon-γ treatment. Collectively, these data show that leishmania aldolase is a novel SHP-1 binding and activating protein that contributes to macrophage dysfunction.  相似文献   
44.
Helper T cells from a mutant mouse model, LAT Y136F, hyper-proliferate and cause a severe lymphoproliferative disease that kills the mice by six months of age. LAT Y136F mice carry a tyrosine to phenylalanine mutation in the Linker for Activation of T cells (LAT) gene. This mutation leads to a number of changes in T cells that result in altered cytokine production including increased IL-4 production, increased proliferation, and decreased apoptosis. Hyper-proliferation of the mutant T cells contributes to lymphadenopathy, splenomegaly, and multi-organ T cell infiltration. miRNAs are short non-coding RNAs that regulate expression of cohorts of genes. This study investigates which miRNAs are expressed in LAT Y136F T cells and compares these to miRNAs expressed in wild type T cells that are undergoing proliferation in two other settings. The first setting is homeostatic proliferation, which was modeled by adoptive transfer of wild type T cells into T cell-deficient mice. The second setting is proliferation in response to infection, which was modeled by infection of wild type mice with the nematode H. polygyrus. By comparing miRNA expression in these three proliferative states (LAT Y136F hyper-proliferation, homeostatic proliferation and proliferation in response to H. polygyrus infection) to expression in wild type naïve CD4+ T cells, we found miRNAs that were highly regulated in all three proliferative states (miR-21 and miR-146a) and some that were more specific to individual settings of proliferation such as those more specific for LAT Y136F lymphoproliferative disease (miR-669f, miR-155 and miR-466a/b). Future experiments that modulate levels of the miRNAs identified in this study may reveal the roles of these miRNAs in T cell proliferation and/or lymphoproliferative disease.  相似文献   
45.
Nine field strains of fowlpox virus (FPV) isolated during a 24-year span from geographically diverse outbreaks of fowlpox in the United States were screened for the presence of reticuloendotheliosis virus (REV) sequences in their genomes by PCR. Each isolate appeared to be heterogeneous in that either a nearly intact provirus or just a 248- or 508-nucleotide fusion of portions of the integrated REV 5' and 3' long terminal repeats (LTRs) was exclusively present at the same genomic site. In contrast, four fowlpox vaccines of FPV origin and three originating from pigeonpox virus were genetically homogeneous in having retained only the 248-bp LTR fusion, whereas two other FPV-based vaccines had only the larger one. These remnants of integrated REV presumably arose during homologous recombination at one of the two regions common to both LTRs or during retroviral excision from the FPV genome. Loss of the provirus appeared to be a natural event because the tripartite population could be detected in a field sample (tracheal lesion). Moreover, the provirus was also readily deleted during propagation of FPV in cultured cells, as evidenced by the detection of truncated LTRs after one passage of a plaque-purified FPV recombinant having a "genetically marked" provirus. However, the deletion mutants did not appear to have a substantial replicative advantage in vitro because even after 55 serial passages the original recombinant FPV was still prevalent. As to the in vivo environment, retention of the REV provirus may confer some benefit to FPV for infection of poultry previously vaccinated against fowlpox.  相似文献   
46.
47.
A 46-kDa glycoprotein, gp46, which binds collagen has been purified to homogeneity from L6 rat skeletal myoblasts. The procedure involves extraction of crude myoblast membranes with 1% sodium dodecyl sulfate followed by concanavalin A affinity chromatography and preparative gel electrophoresis. The sequence of 15 N-terminal amino acids had some resemblance to a sequence in myosin light chains. The oligosaccharide chains of the glycoprotein can be released by treatment with endoglycosidase H, suggesting that gp46 has high-mannose type of glycans. Galactose and sialic acid are not detected in the purified protein. gp46 is widely distributed and conserved in different cell lines as determined by immunoblotting using a monoclonal anti-gp46 antibody. High levels of gp46 were found in several fibroblastic and myogenic cell lines, but not in a hematopoietic cell line. Undifferentiated F9 embryonal carcinoma cells lacked gp46 but the glycoprotein was induced when the cells were made to differentiate in the presence of retinoic acid. Broad survey of gp46 in different cell lines also suggests that it is present mainly in those cell lines which attach to the substratum and produce collagens. Although the function of gp46 is not yet known, the evidence suggests that it is developmentally regulated and is probably involved in the synthesis or assembly of collagen in the endoplasmic reticulum.  相似文献   
48.
Murraya koenigii (L.) Spreng (Curry leaf) is a commercially important medicinal plant in South Asia, containing therapeutically valuable carbazole alkaloids (CAs). Thus, the quantitative evaluation of these compounds from different climatic zones of India are an important aspect for quality assessment and economic isolation of targeted compounds from the plant. In this study, quantitative estimation of CAs among 34 Indian natural populations of M. koenigii was assessed using UPLC/MS/MS. The collected populations represent the humid subtropical, tropical wet & dry, tropical wet, semi-arid, arid, and montane climatic zones of India. A total of 11 CAs viz. koenine-I, murrayamine A, koenigine, koenimbidine, koenimbine, O-methylmurrayamine A, girinimbine, mahanine, 8,8’’-biskoenigine, isomahanimbine, and mahanimbine were quantified using multiple reaction monitoring (MRM) experiments within 5.0 min. The respective range for natural abundance of CAs were observed as 0.097–1.222, 0.092–5.014, 0.034–0.661, 0.010–1.673, 0.013–7.336, 0.010–0.310, 0.010–0.114, 0.049–5.288, 0.031–1.731, 0.491–3.791, and 0.492–5.399 mg/g in leaves of M. koenigii. The developed method shown linearity regression coefficient (r2>0.9995), LOD (0.003–0.248 ng/mL), LOQ (0.009–0.754 ng/mL), and the recovery was between 88.803–103.729 %. The bulk of these CAs were recorded in their highest concentrations in the humid subtropical zone, followed by the tropical wet & dry zones of India. Further, principal component analysis (PCA) was performed which differentiated the climatic zones according to the dominant and significant CAs contents within the populations. The study concludes that the method established is simple, rapid, with high sample throughput, and can be used as a tool for commercial purposes and quality control of M. koenigii.  相似文献   
49.
50.
Deciphering the most promising strategy for the evolution of potential wound-healing therapeutics is one of the greatest challenging affairs to date. The development of peptide-based smart scaffolds with innate antimicrobial, anti-inflammatory, and antioxidant properties is an appealing way out. Aligned to the goal a set of Hydrogelators I–IV were developed utilizing the concept of chiral orchestration in diphenylalanine fragment, such that the most potent construct with all the bench marks namely mechanoresponsiveness, biocompatibility, consistent antimicrobial and antioxidant properties, could be fished out from the design. Interestingly, our in vitro Antifungal and Lipid peroxidation analysis identified the homochiral isomer Boc-δ-Ava-L-Phe-L-Phe-OH (Hydrogelator I ), as an ideal candidate for the wound healing experiment, so we proceeded for the in vivo histopathological and antioxidant measurements in Wister rats. Indeed the wound images obtained from the different sets of animals on the 14th day of treatment demonstrated that with increased recovery time, hydrogelator I displayed a significant reduction in the lesion diameter compared to the marketed drug, and negative control. Even the histopathological measurements using H & E staining demonstrated diminished tissue destruction, neutrophil infiltration necrosis, and lymphatic proliferation in the hydrogelators, in comparison to others, backed by in vivo lipid peroxidation data. Overall our investigation certifies hydrogelator I as an effective therapeutic for managing the wound healing complication.  相似文献   
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