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71.
Summary St. John's wort (Hypericum perforatum L.) is a medicinal plant used in the treatment of neurological disorders and has been recently shown to have anticancer potential. The principle medicinal components of St. John's wort are hypericin. pseudohypericin, and hyperforin. One of the problems associated with medicinal plant preparations including St. John's wort is the extreme variability in the phytochemical content, mostly due to environmental variability, and biotic and abiotic contamination during cropping. The current study was undertaken to transplant St. John's wort plants from in vitro bioreactors in a closed controlled environment system (CCES) with CO2 enrichment for the optimized production of biomas and phytochemicals. The growth and levels of hypericin, pseudohypericin, and hyperforin in plants grown in CCES were compared with those of the greenhouse and in vitro-grown plants. The environmental parameters in the greenhouse were found to be variable whereas in the CCES these parameters were controlled. Generally, all the growth parameters and hypericin and psendohypericin levels were significantly higher in the plants grown in the CCES. These results provide the first indication that growing St. John's wort plants, under CO2 enrichment in a closed environment system can enhance the biomass and medicinal contents. The adaptation of this growing system may be useful for the production of optimized products of St. John's wort and other medicinal species.  相似文献   
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Summary The distribution of acidic and basic fibroblast growth factors (aFGF, bFGF) was mapped during mouse embryonic palate development. Generally, they localised most intensely in the basement membrane and epithelia rather than the mesenchyme. Localisation was predominantly restricted to the palatal nasal, and medial edge epithelia. Staining was particularly intense in the medial edge epithelia at the time of mid-line epithelial seam formation. Intense staining persisted in the epithelia of the degenerating seam and later in the oral and nasal epithelial triangles. Mouse embryonic palate mesenchyme (MEPM) cells cultured in vitro on a variety of substrata (on plastic, on the surface of a collagen gel and within a collagen gel) responded to treatment with aFGF or bFGF. These responses were modulated by the culture substratum. The FGFs stimulated MEPM cell proliferation on plastic and on collagen, but inhibited cell growth in collagen. The FGFs had little effect on protein production when cells were cultured on plastic, but caused a large reduction in on-collagen and incollagen cultures. This reduction was greater in collagenous than non-collagenous proteins. Generally, treatment with FGFs stimulated the production of glycosaminoglycans (GAGs), particularly hyaluronan (HA) and dermatan sulphate (DS). In addition, the size class of HA was shifted to a higher molecular weight form. These data indicate that aFGF and bFGF may play a role in modulating mesenchymal cell matrix biosynthesis, so facilitating palatal epithelial seam degeneration. Correspondence to: M.W.J. Ferguson  相似文献   
74.
Del Pozo  A.  Ovalle  C.  Aronson  J.  Avendaño  J. 《Plant Ecology》2002,159(2):119-130
Burr Medic (Medicago polymorpha) is awidespread, polymorphic annual legume of Mediterranean origin, and as aself-reseeding, highly effective nitrogen fixer it has important value invarious dryland farming systems. In central Chile, it is naturalized along a1000 km long environmental gradient, from an arid zone(29°–31° S) to a perhumid one(37°–38°24' S). Comparative and experimental studiesof its ecotypic differentiation patterns along this gradient should be usefulinelucidating the evolutionary forces at work along environmental gradients, andalso for efforts to select annual legumes for pastures and fallow fieldimprovement in mediterranean climate areas. In this first paper of atwo-part series, we present results of two common-environmentexperiments conducted at a subhumid site in central Chile to compare vegetativeand reproductive traits in 69 populations of Burr Medic collected in 1988 and1994. Multivariate analyses based on 11 phenological and agronomic characters,including phenology and biomass accumulation, winter vigour and degree ofhard-seededness, showed that three principal components (PCs)explained nearly 70% of total variability, in both collections. For thelarger collection (1988), the diagram of dispersion for the first twoPCs – phenology, winter vigour and above-ground biomass –provided good discrimination between accessions from arid-semiarid andhumid-perhumid mediterranean zones. Onset of flowering was positivelycorrelated with both latitude and longitude, as well as mean annualprecipitation/potential evapotranspiration (PP/ETP) ofcollecting site; days from first flower to pod ripening was negativelycorrelated with PP/ETP. In contrast to reports from Syria and Sardinia, noclear trends in Burr Medic seed or pod-related traits was found along theChilean gradient, apart from the concentration of spiny pod accessions in thesouthern, more mesic end of the gradient. Winter vigour (according to asemi-quantitative analysis of growth) was greater in accessions fromthe warmer, arid and semiarid zones than in those from cooler, subhumid tohumidones. Both winter vigour and harvest index were negatively correlated with daysto first flower. Applied and evolutionary aspects of the results are brieflydiscussed.  相似文献   
75.
Background B-type natriuretic peptide (BNP) is secreted from cardiomyocytes and may reflect haemodynamic abnormalities predisposing to atrial fibrillation (AF). We aimed to investigate whether N-terminal pro BNP (NT-proBNP) is associated with newly detected AF in subjects obtained from the general population. Methods From the PREVEND programme (n=8592), we selected all subjects with an available baseline and four-year electrocardiogram and NTproBNP levels at baseline. We excluded subjects with AF at baseline and subjects with a serum creatinine >2.0 mg/dl. Results In total, 6494 subjects were eligible for the prospective analysis (aged 49±12 years, 49.7% men). At four years, AF was detected in 41 (0.6%) subjects. Median NT-proBNP levels at baseline in subjects with newly detected AF after four years was 62.2 (22.6 to 208.5) pg/ml as compared with 35.7 (15.9 to 68.7) pg/ml in those with sinus rhythm (p=0.001). Each 1 standard deviation increment in natural log transformed NT-proBNP was associated with a 54% (5% to 126%, p=0.028) increase in risk for AF after adjustment for other risk factors predisposing to AF. NT-proBNP levels above the sex-specific 80th percentile (97 pg/ml in women and 60 pg/ml in men) were associated with a multivariate odds ratio of 2.65 (1.22 to 5.76, p=0.01) for the occurrence of AF. Conclusion Plasma levels of NT-proBNP predict newly detected AF in subjects obtained from the general population independent of cardiovascular risk factors predisposing to AF. (Neth Heart J 2008;16:73-8.)  相似文献   
76.
Our article uses a new institutional economics (NIE) framework to explore the role of voluntary industry standards in the development and implementation of environmental supplier-management programs in the computer industry. We examine two different voluntary standards, one for the management of design for environment (DfE) in the semiconductor fabrication equipment sector and the other for assessing the implementation and use of environmental management systems throughout the computer industry supply chain. We compare and contrast the two standards to explain why the former was widely adopted and has helped integrate DfE into buyer-supplier relations among adopters, whereas the latter failed to gain acceptance. In line with NIE logic, both standards aimed to lower transaction and customization costs by setting "rules of the game" for interfirm transactions that would help simplify and routinize novel environmental supply-chain programs and activities. Their differential success can be elucidated in terms of how well each met the NIE criteria for remediableness and legitimacy. We conclude that voluntary standards have the potential to play an important role in promoting DfE in industrial supply chains. We further conclude that NIE provides a conceptual framework of great value to industrial ecologists who analyze how industry standards and other institutions help firms move toward more sustainable supply-chain management practices.  相似文献   
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Insulin is a 6 kDa peptide hormone that activates several metabolic processes and cellular growth. Germination studies showed that insulin, vanadyl sulphate (an insulin mimetic compound), tyrphostin (an inhibitor of insulin receptor kinase activity), pinitol (a chiro inositol analogue) and glucose were able to accelerate Canavalia ensiformis (Jack bean) seedling radicle and epicotyl development. Immunofluorescence microscopy analysis showed that proteins binding to insulin, insulin receptor and phosphoserine antibodies are localized in an internal layer of the C. ensiformis seed coat. These results and others previously reported from our laboratory suggest that insulin, insulin receptor and phosphoserine proteins could be components of signalling pathways akin to those present in animals.  相似文献   
80.
PM2.5和PM10已成为我国大部分城市空气的首要污染物.本文通过分析南昌市2013—2015年的空气PM2.5和PM10质量浓度、气象因素、交通流量的监测数据,探讨了空气颗粒物污染的时空动态规律以及气象、交通对颗粒物浓度变化的影响.结果表明: 2013、2014、2015年,南昌市PM2.5浓度(70.92 μg·m-3>53.70 μg·m-3>43.65 μg·m-3)、PM10浓度(119.72 μg·m-3>86.11 μg·m-3>73.32 μg·m-3)逐年降低,并呈现出夏季低(PM2.5和PM10平均浓度分别为36.74、69.20 μg·m-3)、冬季高(PM2.5和PM10平均浓度分别为74.29、111.64 μg·m-3)的季节动态和由城市中心向郊区递减的城乡梯度变化; PM2.5/PM10值(0.595>0.584>0.557)逐年降低,并且表现出城市中心高、城市边缘低的空间分布格局;PM2.5、PM10浓度受到多种气象因素的影响,与气压、温度、相对湿度、风速、降水量、日照时数显著相关,各种气象因子对PM2.5、PM10浓度的影响存在差异;车流量会显著提高周边PM2.5浓度,但对PM10浓度影响不明显.  相似文献   
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