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排序方式: 共有125条查询结果,搜索用时 31 毫秒
1.
Summary Byssochlamys fulva was grown in two fermentation media using shake flasks, stirred fermentor and disc fermentor under conditions to give maximum production of pectolytic enzymes. Only polygalacturonase activity was detected in the culture filtrates during all fermentations. In all production conditions studied, no evidence of pectin methylesterase, pectin lyase, cellulase or proteinase activities were found. The maximum polygalacturonase activity (4.5 units/ml) was achieved when the microorganism was grown on medium II in shake flasks at pH 4.0–4.5 and 30°C after 12 days of fermentation.  相似文献   
2.
Summary Proteins of uterine fluid and lung homogenates of the rabbit were separated by gel and ion exchange chromatography. Purified protein fractions were used for immunisation and antiserum production. By means of several absorptions, six monospecific antisera against uteroglobin and five other proteins were obtained. Using immunohistochemistry, four of them could be localised in the uterine epithelium from oestrus and the first and the seventh day post coitum, and also in the blastocyst. The present study indicates the involvement of different endometrial cells in the synthesis and release of the various proteins of uterine secretion.Supported by grant Ki 154/6-7 from the Deutsche Forschungsgemeinschaft  相似文献   
3.
People use medicinal plants as diet, and for treatment of infectious and noninfectious diseases and they use brief procedures like frying and cooking to do so. Medicinal plants; Moringa oleifera, Azadirachta indica, and Lepidium sativum which is believed to have active components that help to treat and manage various diseases were investigated for their antibacterial activities against Staphylococcus aureus, Salmonella Typhi, Streptococcus agalactiae and Shigella boydii. Solvent methanol and aqueous were used for extraction of crudes by means of maceration. Susceptibility testing was determined by using disc diffusion method and Minimum inhibitory concentration was determined by broth dilution method. Heat treated plant material activity against test pathogen was aimed to identify resistance capacity of plant material at different interval of time and temperature. All plant extracts under study was active against all tested pathogen after exposure to 45 °C for 30 min. The antibacterial activities of the non-heat-treated extracts of Azadirachta indica were relatively low; the results of this study show that extracts of Azadirachta indica have better residual antibacterial activities. Methanol extracts of all plant leaves showed highest activity as compared to the aqueous extracts. This is probably assigning the choice of extraction solvent for extracting desired active phytochemical from plants. Many of the people in the study area were illiterate and they did not have awareness about the ways use of medicinal plants. They use the medicinal plants by cooking and frying for different purposes. In the main, plant material can be affected as the temperature of treatment is increases with respect to various times of exposures.  相似文献   
4.
对分布在青藏高原东缘高寒草甸常见种长毛风毛菊的6个海拔梯度(3200~3850m)18个居群的繁殖分配进行了研究,结果表明:长毛风毛菊随海拔的升高个体和营养器官减小,繁殖的投入增加;随着海拔的升高,长毛风毛菊的个体管状小花数目和种子数目减少,管状小花重量和百粒重增大;个体管状小花的数目及重量和个体种子的数目及重量间存在权衡关系;长毛风毛菊的个体大小和繁殖分配存在负相关关系。在资源受限的环境下,长毛风毛菊以减少管状小花数目和种子的数目来增加管状小花重量和百粒重,是保证有性繁殖成功的策略之一。  相似文献   
5.
Metastatic cancer cells are highly plastic for the expression of different tumor phenotype hallmarks and organotropism. This plasticity is highly regulated but the dynamics of the signaling processes orchestrating the shift from one cell phenotype and metastatic organ pattern to another are still largely unknown. The scaffolding protein NHERF1 has been shown to regulate the expression of different neoplastic phenotypes through its PDZ domains, which forms the mechanistic basis for metastatic organotropism. This reprogramming activity was postulated to be dependent on its differential phosphorylation patterns. Here, we show that NHERF1 phosphorylation on S279/S301 dictates several tumor phenotypes such as in vivo invasion, NHE1-mediated matrix digestion, growth and vasculogenic mimicry. Remarkably, injecting mice with cells having differential NHERF1 expression and phosphorylation drove a shift from the predominantly lung colonization (WT NHERF1) to predominately bone colonization (double S279A/S301A mutant), indicating that NHERF1 phosphorylation also acts as a signaling switch in metastatic organotropism.  相似文献   
6.
目的:评价针刺联合红外线照射治疗腰椎间盘突出症的临床疗效。方法:选择2010 年9 月~2012 年1 月我院收治的90 例 腰椎间盘突出症患者为研究对象,并将其随机分为对照组和治疗组,每组45 例。对照组患者给予药物治疗,而治疗组患者给予针 刺联合红外线照射治疗,治疗后评价和比较两组患者的临床疗效及腰腿痛的改善情况。结果:针刺联合红外线照射治疗腰椎间盘 突出症显效率为62.2%,药物组显效率为26.7%,两组有显著性差异(P<0.05)。治疗后,治疗组患者腰腿痛疼痛评分明显低于对照 组,差异有统计学意义(P<0.01)。结论:以针刺联合红外线照射治疗腰椎间盘突出症的临床疗效肯定,值得临床推广。  相似文献   
7.
The Scutellaria is a Labiatae genus (subfamily Scutellarioideae) with a highly specialised floral structure. The genus is characterised by a peculiar two‐lobed calyx with a projecting appendage, named the scutellum. Here, we present a detailed analysis of floral development, using epi‐illumination light microscopy, to clarify open questions about its floral organisation. Floral whorls appeared in an acropetal sequence, with a marked temporal overlap of petal and stamen appearance. Organ appearance in each whorl proceeded unidirectionally from the abaxial to the adaxial side. Significant developmental features included the formation of the scutellum, reduction of sepal lobes and formation of a three‐lobed nectary disc. Our study revealed that both loss of organ initiation and fusion of primordia are responsible for the reduction in sepal members in Scutellaria. The nectary structure was markedly different from most other studied Lamiaceae.  相似文献   
8.
The coordination between floret initiation and tissue expansion has been studied and quantified in the apical meristem of sunflower (Helianthus annuus) plants grown under different light availability. A method was developed to quantify tissue expansion in the meristem during floret initiation from measurements of meristem area, number of florets and primordium size. Initially, floret initiation and tissue expansion occurred simultaneously at the meristem surface. The duration of this phase remained unchanged across environments, whereas the rate of tissue expansion varied greatly. Floret initiation rate depended on meristem initial size and tissue-expansion rate. Thereafter, floret initiation continued without tissue expansion in the meristem, resulting in a rapid decrease of meristem area. A set of equations was proposed to predict floret initiation rate and floret number as a function of the rates of tissue expansion in the meristem before and during floret initiation. This formalism demonstrated the role of tissue expansion in determining the final number of florets, and provided a framework to analyse the response of floret initiation to genotype and environment.  相似文献   
9.
Human HTRA1 is a highly conserved secreted serine protease that degrades numerous extracellular matrix proteins. We have previously identified HTRA1 as being up-regulated in osteoarthritic patients and as having the potential to regulate matrix metalloproteinase (MMP) expression in synovial fibroblasts through the generation of fibronectin fragments. In the present report, we have extended these studies and investigated the role of HTRA1 in the pathogenesis of intervertebral disc (IVD) degeneration. HTRA1 mRNA expression was significantly elevated in degenerated disc tissue and was associated with increased protein levels. However, these increases did not correlate with the appearance of rs11200638 single nucleotide polymorphism in the promoter region of the HTRA1 gene, as has previously been suggested. Recombinant HTRA1 induced MMP production in IVD cell cultures through a mechanism critically dependent on MEK but independent of IL-1β signaling. The use of a catalytically inactive mutant confirmed these effects to be primarily due to HTRA1 serine protease activity. HTRA1-induced fibronectin proteolysis resulted in the generation of various sized fragments, which when added to IVD cells in culture, caused a significant increase in MMP expression. Furthermore, one of these fragments was identified as being the amino-terminal fibrin- and heparin-binding domain and was also found to be increased within HTRA1-treated IVD cell cultures as well as in disc tissue from patients with IVD degeneration. Our results therefore support a scenario in which HTRA1 promotes IVD degeneration through the proteolytic cleavage of fibronectin and subsequent activation of resident disc cells.  相似文献   
10.
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