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981.

Introduction  

Previous studies have shown that the number of myoblastically differentiated fibroblasts known as myofibroblasts (MFs) is significantly increased in stiff joint capsules, indicating their crucial role in the pathogenesis of post-traumatic joint stiffness. Although the mode of MFs' function has been well defined for different diseases associated with tissue fibrosis, the underlying mechanisms of their regulation in the pathogenesis of post-traumatic joint capsule contracture are largely unknown.  相似文献   
982.
Tumor cells might resist therapy with ionizing radiation (IR) by non-homologous end-joining (NHEJ) of IR-induced double-strand breaks. One of the key players in NHEJ is DNA-dependent protein kinase (DNA-PK). The catalytic subunit of DNA-PK, i.e. DNA-PKcs, can be inhibited with the small-molecule inhibitor NU7026. In the current study, the in vitro potential of NU7026 to radiosensitize neuroblastoma cells was investigated. DNA-PKcs is encoded by the PRKDC (protein kinase, DNA-activated, catalytic polypeptide) gene. We showed that PRKDC levels were enhanced in neuroblastoma patients and correlated with a more advanced tumor stage and poor prognosis, making DNA-PKcs an interesting target for radiosensitization of neuroblastoma tumors. Optimal dose finding for combination treatment with NU7026 and IR was performed using NGP cells. One hour pre-treatment with 10 μM NU7026 synergistically sensitized NGP cells to 0.63 Gy IR. Radiosensitizing effects of NU7026 increased in time, with maximum effects observed from 96 h after IR-exposure on. Combined treatment of NGP cells with 10 μM NU7026 and 0.63 Gy IR resulted in apoptosis, while no apoptotic response was observed for either of the therapies alone. Inhibition of IR-induced DNA-PK activation by NU7026 confirmed the capability of NGP cells to, at least partially, resist IR by NHEJ. NU7026 also synergistically radiosensitized other neuroblastoma cell lines, while no synergistic effect was observed for low DNA-PKcs-expressing non-cancerous fibroblasts. Results obtained for NU7026 were confirmed by PRKDC knockdown in NGP cells. Taken together, the current study shows that DNA-PKcs is a promising target for neuroblastoma radiosensitization.  相似文献   
983.
Remote sensing permits the identification of locations and area extent where particular crops are cultivated across larger regions. This requires the availability of crop- and region-specific algorithms. We developed an approach to identify oilseed rape fields in Northern Germany. The remote sensing data sources and main processing steps are described. The derived cultivation density information provides an overview of the fine-scale spatial structure and crop neighbourhood relations in Northern Germany as one of the main oilseed rape cultivation regions in Europe. Geographical Information System (GIS) analyses involving buffer operations allowed to identify those parts of the region, where the highest interaction potential of GM crops and conventional crops would occur if GM varieties were admitted for cultivation. Cultivation density and field sizes in combination were used to indicate the interaction intensity as a marker for observation requirement (environmental monitoring) and for those potential risks that relate to density parameter. Conclusions can be drawn for the feasibility of coexistence measures when neighbouring farmers have to co-operate to keep separation distances between GM crop cultivation and conventional varieties. Together with other data sources, the results of satellite image analysis can be used as input data for up-scaling small-scale model results. Remote sensing data allow to specify, which field density parameter must be chosen to cover the regional variability of cultivation conditions, in particular the regional distribution of field sizes and field density.  相似文献   
984.
A PstI RFLP of the LACI gene   总被引:1,自引:0,他引:1       下载免费PDF全文
  相似文献   
985.
This paper describes the results of the archaeobotanical examination of early medieval occupation deposits (8th to 11th centuries A.D.) at Douai, northern France. Carbonized as well as waterlogged seeds and fruits were recovered in great numbers. In addition to the macrofossil analyses, a palynological examination of occupation deposits was carried out. Bread wheat (Triticum aestivum) was the most common cereal, followed by rye (Secale cereale). Common oat (Avena sativa) and hulled barley (Hordeum vulgare) must have played a fairly modest role. In addition to cereals, field pea (Pisum sativum) was an important crop plant. Four types of plum (Prunus domestica) fruitstones are distinguished. Sweet cherry (Prunus avium) as well as sour cherry (P. cerasus) were cultivated. Other cultivated fruit trees included peach (Prunus persica) and medlar (Mespilus germanica). Sloe (Prunus spinosa) fruits, including those of the var. macrocarpa, were gathered from the wild. The palynological data suggest that the Douai area had virtually been cleared of forest. A comparison between pollen and seed proportions points to serious discrepancies between the macrofossil and microfossil plant records. Weeds of arable land (Secalietea, Polygono-Chenopodietalia) and vegetations of ruderal habitats (Sisymbrietalia, Artemisietalia vulgaris) are well represented. Molinietalia vegetations in the valley of the Scarpe river were probably exploited as hay meadows; good pasture land was provided by the Arrhenateretalia grasslands.  相似文献   
986.
987.
Staining plastic sections with the Romanowsky-Giemsa method is both time-consuming and difficult. This paper reports how the staining time can be reduced to 25 min using microwave irradiation of the staining solution. It is shown that staining results depend on the fixative used, staining temperature, dye concentration and pH of the staining solution as well as on several parameters of the microwave irradiation technique. The staining patterns are improved when compared with those obtained by conventional staining of plastic sections. The colors are more brilliant and greater contrasts are observed. Basophilia, polychromasia, and orthochromasia accompanying red cell maturation are more pronounced. For white cell maturation the initial appearance of specific granules (neutrophil, basophil, and eosinophil) is more evident. Thus, cell classification is easily accomplished using the described technique. It is suggested that microwave-stimulated staining be considered for routine use.  相似文献   
988.
989.
990.
Minimal concentrations of oxygen are limiting factors for limnic biocenoses. It should therefore be possible to use biocenose structure to infer minimal oxygen concentrations that have occured, provided the tolerance of the organisms concerned is known. A simple apparatus used to measure LC50 of oxygen for aquatic insect larvae with tracheal gills is described. Lethal concentrations found in some Ephemeroptera differ between species. Usually, they are strongly temperature dependent. In the species so far studied, confidence intervals are very small and suggest that such insect larvae could be used as bioindicators of minimal oxygen concentrations (even of short term ones), especially in thermically stable waters.  相似文献   
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