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101.
102.
Propolypeptide of von Willebrand factor circulates in blood and is identical to von Willebrand antigen II 总被引:14,自引:0,他引:14
P J Fay Y Kawai D D Wagner D Ginsburg D Bonthron B M Ohlsson-Wilhelm S I Chavin G N Abraham R I Handin S H Orkin 《Science (New York, N.Y.)》1986,232(4753):995-998
The generally mild bleeding disorder of von Willebrand disease is associated with abnormalities of two distinct plasma proteins, the large multimeric von Willebrand factor (vWF), which mediates platelet adhesion, and von Willebrand antigen II (vW AgII), which is of unknown function. The two proteins were found to have a common biosynthetic origin in endothelial cells and megakaryocytes, which explains their simultaneous absence in the severe form of this hereditary disease. Shared amino acid sequences from a 100-kilodalton plasma glycoprotein and from vW AgII are identical to amino acid sequences predicted from a complementary DNA clone encoding the 5' end of vWF. In addition, these proteins have identical molecular weights and immunologic cross reactivities. Monoclonal antibodies prepared against both proteins recognize epitopes on the pro-vWF subunit and on a 100-kilodalton protein that are not present on the mature vWF subunit in endothelial cell lysates. In contrast, polyclonal antibodies against vWF recognize both pro-vWF and vWF subunits. Thus, the 100-kilodalton plasma glycoprotein and vW AgII are identical proteins and represent an extremely large propolypeptide that is first cleaved from pro-vWF during intracellular processing and then released into plasma. 相似文献
103.
The presence of fibroblast growth factor in the frog egg: its role as a natural mesoderm inducer 总被引:30,自引:0,他引:30
D Kimelman J A Abraham T Haaparanta T M Palisi M W Kirschner 《Science (New York, N.Y.)》1988,242(4881):1053-1056
104.
105.
Z. Abraham S. K. Malik Gangadhar Eashwar Rao S. Lakshmi Narayanan S. Biju 《Genetic Resources and Crop Evolution》2006,53(2):401-406
A collaborative crop specific exploration and collection mission to collect the germplasm and to study the population size
of male and female/hermaphrodite trees of Malabar tamarind [Garcinia cambogia (Gaertn.) Desr.] in the area of its diversity was undertaken during July 2002 in Kerala and Karnataka. A total of 56 accessions
of Malabar tamarind were collected. Two collections of Malabar tamarind were found to be very specific because of the uncommon
fruit colour, which is pinkish red. All the collected accessions are grown at National Bureau of Plant Genetic Resources (NBPGR)
Regional Station, Thrissur for characterisation and conservation. Extensive range of variability was found in fruit colour,
shape, size and nature of branching and canopy of trees. Characterisation of 13 fruit and five seed characters was done for
51 accessions. The variability was found to be maximum for nipple length (74.8%) and minimum for fruit girth (12.8%). Two
promising accessions were identified based on mean fruit weight (161 g) in IC 354028 and mean rind thickness (15 mm) and mean
rind weight (125 g) in IC 354019. 相似文献
106.
Murphy BT MacKinnon SL Yan X Hammond GB Vaisberg AJ Neto CC 《Journal of agricultural and food chemistry》2003,51(12):3541-3545
Bioactivity-guided fractionation of cranberry fruit was used to determine the identity of triterpenoid esters from Vaccinium macrocarpon, which inhibit tumor cell growth and may play a role in cancer prevention. In our previous study, a fraction from whole fruit exhibited tumor cell growth inhibition in vitro. The major components of this fraction were isolated by chromatographic separation of ethyl acetate extracts, purified by semipreparative HPLC, and identified by NMR as cis- (1) and trans- (2) isomers of 3-O-p-hydroxycinnamoyl ursolic acid. These triterpenoid esters have not been previously reported in Vaccinium fruit. Bioassay of the purified triterpene cinnamates in tumor cell lines in vitro showed slightly greater activity of compound 1 in most cell lines, with GI(50) values of approximately 20 microM in MCF-7 breast, ME180 cervical and PC3 prostate tumor cell lines. Quercetin was slightly less active than 1, while cyanidin-3-galactoside exhibited much lower cytotoxicity, with GI(50) greater than 250 microM in all cell lines. Phenylboronic acid (3) was also isolated from the fruit but showed insignificant antitumor activity. 相似文献
107.
Spernath A Yaghmur A Aserin A Hoffman RE Garti N 《Journal of agricultural and food chemistry》2002,50(23):6917-6922
Water-dilutable food-grade microemulsions consisting of ethoxylated sorbitan esters, and in some cases blended with other emulsifiers, water, (R)-(+)-limonene, ethanol, and propylene glycol, have been prepared. These microemulsions are of growing interest to the food industry as vehicles for delivering and enhancing solubilization of natural food supplements with nutritional and health benefits. Lycopene, an active natural lipophilic antioxidant from tomato, has solubilized in water-in-oil, bicontinuous, and oil-in-water types of microemulsions up to 10 times the oil [(R)-(+)-limonene] dissolution capacity. The effects of aqueous-phase dilution, nature of surfactant (hydrophilic-lypophilic balance), and mixed surfactant on solubilization capacity and solubilization efficiency were studied. Structural aspects studied by self-diffusion NMR were correlated to the solubilization capacity, and transformational structural changes were identified. 相似文献
108.
Selecting a healthy diet score: lessons from a study of diet and health in early old age (the Boyd Orr cohort) 总被引:2,自引:0,他引:2
OBJECTIVES: To describe the selection and modification of an appropriate diet score to assess diet quality in early old age. DESIGN AND SETTING: Cross-sectional analyses of the Boyd Orr cohort - a long-term follow-up of men and women whose families took part in a survey of diet and health in pre-war Britain. Dietary data were obtained from a 113-item food-frequency questionnaire. A nine-item Healthy Diet Indicator (HDI) developed by Huijbregts and colleagues was identified from the literature and modified because some dietary variables were unavailable and to accord more closely with recommendations of the UK Committee on Medical Aspects of Food Policy. SUBJECTS: In total, 1475 traced, surviving cohort members aged 60 years and over. RESULTS: Modification resulted in a 12-item Healthy Diet Score (HDS). We found that about half the variation in the HDS was explained by variation in the HDI (r=0.71). There was, however, little misclassification of subjects (<10%) into extreme thirds of the distribution by the HDS compared with the HDI. Items of the score most strongly correlated with overall score were saturated fat (r=-0.57), red meat (r=-0.46), dietary fibre (r=0.58), fruit and vegetables (r=0.54) and percentage energy from carbohydrates (r=0.51). Modifying existing items had greater impact on agreement between HDI and HDS than the addition of new items. CONCLUSIONS: The selection and modification of diet scores is more complicated than often assumed. Furthermore, modest changes to an existing score can produce a score that is different from the original, and although it was not possible to test this issue, it may no longer predict subsequent health experience. 相似文献
109.
Amani S.Y. Al-Zaidan Abrar Akbar Hussain Bahbahani Salim Y. Al-Mohanna Biju Kolattukudy Varun Balakrishna 《水产资源保护:海洋与淡水生态系统》2021,31(4):802-817
- To our knowledge, this is the first inclusive assessment of the status of Sparidae fisheries in the territorial waters of Kuwait, integrating information on catch trends, consumer preferences, recreational fishing behaviour, and molecular based identification of fish species by DNA barcoding
- Fisheries landing data were obtained from the official fisheries bulletin released by the Kuwait Central Statistical Bureau. Surveys were conducted to assess consumer preferences on seabream species, landed seabream species, and the behaviour of recreational anglers towards seabream species. DNA barcodes were generated to authenticate commercial seabream using the mitochondrial cytochrome c oxidase subunit I (COXI) gene and then compared with GenBank sequence entries; these sequences were then used to construct a neighbour-joining (NJ) phylogenetic tree.
- Yellowfin seabream Acanthopagrus latus was the prime and most favoured commercial seabream species (45%), followed by Sparidentex hasta, which was the top-rated secondary, unassessed seabream species. Approximately 54% of households conduct recreational fishing more than twice a month, and most (77%) primarily target S. hasta and Ac. latus. Consumer demand for secondary seabreams, which were not assessed and are listed in the bulletin under the category ‘others’, was evident.
- The NJ phylogenetic tree revealed that Arabian Gulf seabreams, including those of Kuwait, are genetically different from their counterparts inhabiting neighbouring waters.
- The data presented here highlight the urgency to modify the existing fisheries list using accurate identification tools, such as DNA barcoding, for the sustainable and conservation-oriented management of local fisheries, which are in decline.
110.
Ingrid Wesström Barbro Ulén Abraham Joel Göran Johansson Lovisa Stjernman Forsberg 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2015,65(3):228-238
Leaching losses of nitrogen (N), phosphorus (P) and potassium (K) from arable land can be high, with N and P contributing significantly to the eutrophication of lakes and coastal waters. This study examined whether agriculture management and drain repair changed the chemical properties of shallow groundwater and affected nutrient leaching in the field. The hydrology of a subsurface-drained agricultural observation field included in the Swedish water quality monitoring programme was simulated for the period 1976–2006 using the process-based, field-scale model DRAINMOD. On the assumption that the drainage system operated similarly before and after repair, 54% more water was assigned to low-moderate flow events. Measured concentrations of sulphate-sulphur (SO4-S), sodium (Na), chloride (Cl) and potassium (K) were significantly lower in shallow groundwater in the period before drainage system repair (1980–1998) than afterwards (1998–2010). The concentrations were also significantly correlated with the corresponding concentrations in near-simultaneously sampled drain water. A similar connection was not observed for Na and Cl in the period before drain repair. Elevated concentrations of nitrate-nitrogen (NO3-N) were recorded both in shallow groundwater and in drainage water from 1998 to 2010, especially after incorporation of chicken manure into the soil in 1998. Based on simulated discharge (assuming a functioning measuring station throughout), estimated flow-weighted mean NO3-N concentration in drainage water increased from 5.6 mg L?1 (1977–1998) to 15.7 mg L?1 in the period 1998–2000. Simultaneously, mean NO3-N concentration in shallow groundwater increased from 0.2 to 4.0 mg L?1, and then to 4.8 mg L?1 in the period 2000–2012. It was estimated that after drain repair, a greater proportion of infiltrated NO3-N entered the receiving stream directly via the outlet of the tile drainage system close to the field's monitoring station than was the case before repair. 相似文献