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41.
In order to analyze the interrelationships between free erythrocyte protoporphyrins and the usual iron intake in adult students, biochemical, and hematological values, and dietary daily intake, obtained using the recall method during seven days, were studied. Hematocrit (Hto.), hemoglobin (Hb) and free erythrocyte protoporphyrins (FEP) were determined in a group of 145 female university students, healthy according to the standard parameters of the Buenos Aires University Health Department. Mean iron intake was 23.0 +/- 1.5 mg per day, about 44% being provided by animal sources; 74.5% of the population was within the recommended daily intake according to FAO/WHO; only 0.7% of the population did not cover protein requirements while 35% did not cover energy needs. Hto. and Hb were below normal levels in 7.8% of the population when compared with standards according to ICNND. To obtain information about normal values to FEP, expressed as microgram/100 ml red cells (FEP% r.c.) and FEP/Hb ratio, the group of students with adequate intake of energy and proteins who had normal values for Hb and Hto. was selected. This group, including 94 women, had a mean FEP% r.c. of 15.71 +/- 7.26 and a mean FEP/Hb ratio of 0.44 +/- 0.21. There was observed an inverse correlation between FEP% r.c. and FEP/Hb with total iron intake (r = 0.80 and r = 0.78, respectively) and between FEP% r.c. and Hb concentration (r = 0.81). These results confirm the usefulness of the free erythrocyte protoporphyrins determination as a good index of iron stores and usual intake of this population.  相似文献   
42.
Vladimir Novotny 《Wear》1983,90(2):221-223
The development of a technique for the condition monitoring of agricultural machinery such as diesel engines and hydraulic and transmission systems is outlined. The application of ferrography for this purpose and the cost savings effected are discussed.  相似文献   
43.
For Gadoid fishes, formaldehyde can be generated in tissues in huge amounts during endogenous enzymatic degradation of natural osmoprotectant trimethylamine-N-oxide. This paper describes two enzymatic methods for assay of formaldehyde in fish food products using alcohol oxidase (AOX) and formaldehyde dehydrogenase (FdDH) isolated from the thermotolerant methylotrophic yeast Hansenula polymorpha. AOX-based method exploits an ability of the enzyme to oxidise a hydrated form of formaldehyde to formic acid and hydrogen peroxide monitored in peroxidase-catalysed colorimetric reaction. In FdDH-based method, a monitored coloured formazane is formed from nitrotetrazolium salt during reduction by NADH, produced in formaldehyde-dependent reaction. It was demonstrated an applicability of both methods for assay of formaldehyde in fish products. The optimal protocols for analysis procedures have been elaborated and analytical parameters of both enzymatic methods have been established. The both methods were demonstrated that some fish products (hake and cod) contain high formaldehyde concentrations (up to 100 mg/kg wet weight).  相似文献   
44.
Lactic acid bacteria‐induced fermentation of fish was tested with the purpose of developing a novel fish food product with desired meat properties. Three selected lactic acid bacteria strains, isolated from lightly preserved fish products, were inoculated into minced frozen fillet of yellowfin tuna, and changes in fish properties were observed during 52 days of storage at 8 °C. Organoleptic, bacteriological and biochemical studies (pH, histamine, TVB‐N, malonaldehyde) and shelf‐life measurements suggest that Leuconostoc mesenteroides could be considered as a possible starter culture for fish fermentation, but additional experiments should be performed. © 2000 Society of Chemical Industry  相似文献   
45.
46.
Beetroot (Beta vulgaris) pomace, processing by-product from food industry, was investigated in this work as a starting raw material. The contents of phenolics (1.87–11.98 mg GAE/g of dry weight) and betalains (0.75–3.75 mg betalains/g of dry weight) in the extracts were determinated spectrophotometrically. Some individual phenolic compounds, including ferulic, vanillic, p-hydroxybenzoic, caffeic and protocatehuic acids, were identified and quantified by HPLC. The antioxidative activity of beetroot extracts was tested using DPPH, hydroxyl and superoxide anion radicals by ESR spectroscopy. IC50OH (0.05–0.108 mg/ml), IC50DPPH (0.183–0.333 mg/ml), and IC50O2- (0.198–1.000 mg/ml) were calculated. The regression analysis produced moderate to high correlation coefficients between the scavenging activities and phenolics, and some individual phenolic compounds which indicated that beetroot pomace may be used as functional food ingredient. Cell growth effects were determined in MCF7 and MRC-5 cell lines, using SRB assay. IC50 values were in the range of 362.478–503.525 and 383–587.880 μg/ml in MRC-5 and MCF7, respectively.  相似文献   
47.
Ethanol–water (70:30, v/v) extracts from the bran of rice seeds from twenty one pigmented and one nonpigmented rice cultivars were evaluated for antioxidative activities using the following tests: inhibition of peroxidation of linoleic acid; inhibition of peroxidation of rabbit lipid erythrocyte membranes; reduction of potassium ferricyanide, and scavenging of superoxide anions and hydroxyl radicals. With some exceptions, extracts from the pigmented rice seeds had higher antioxidative activity than did the nonpigmented variety. The following pigmented cultivars had the highest antioxidative activities in all tests: Jumlalocal-1, Parnkhari 203, DZ78, LK1-3-6-12-1-1, and Elwee. A significant correlation was also noted between reducing power, inhibition of erythrocyte ghost membrane peroxidation, and superoxide anion and hydroxyl radical scavenging. The results suggest that: (a) ferricyanide reducing power might be a useful and simple index for large-scale evaluation of antioxidative potencies of natural products present in rice; (b) pigmented rice varieties with high antioxidative activities provide a source of antioxidants and a genetic resource to develop new health-promoting rice cultivars.  相似文献   
48.
铝合金钻杆因具有质量轻、比强度高、抗腐蚀性好、低磁等优点,在深井与超深井钻探作业中备受关注.在深井与超深井钻进中,铝合金钻杆需要承受巨大的内外压力,因此有必要对钻杆所能承受的最大内外压力进行计算与试验,对自行研制的Ø147 mm铝合金钻杆进行了静水内、外压试验与弹性力学理论计算校核,7075铝合金钻杆在内压69.51 MPa时持续加压20 min,没有发生泄漏现象;最大抗外压值为107.4 MPa.2024铝合金钻杆在内压48.65 MPa时持续加压20 min,没有发生泄漏现象;最大抗外压值为72.3 MPa.试验表明,铝合金钻杆抗内、外压性能良好,从而保证了铝合金钻杆在深井及超深井钻进时的可靠性.  相似文献   
49.
Active distribution network(ADN), as a typically cyber-physical system, develops with the evolution of Internet of Things(Io Ts), which makes the network vulnerable to cybersecurity threats. In this paper, the eavesdropping attacks that lead to privacy breaches are addressed for the Io T-enabled ADN. A privacy-preserving energy management system(EMS) is proposed and empowered by secure data exchange protocols based on the homomorphic cryptosystem. During the information transmission among distributed generators and load customers in the EMS, private information including power usage and electricity bidding price can be effectively protected against eavesdropping attacks. The correctness of the final solutions, e.g., optimal market clearing price and unified power utilization ratio, can be deterministically guaranteed. The simulation results demonstrate the effectiveness and the computational efficiency of the proposed homomorphically encrypted EMS.  相似文献   
50.
The synthesis of new modified indolo[3,2-c]quinoline ligands L(1)-L(8) with metal-binding sites is reported. By coordination to ruthenium- and osmium-arene moieties 16 complexes of the type [(η(6)-p-cymene)M(L)Cl]Cl (1a,b-8a,b), where M is Ru(II) or Os(II) and L is L(1)-L(8), have been prepared. All compounds were comprehensively characterized by elemental analysis, electrospray ionization mass spectrometry, IR, UV-vis, and NMR spectroscopy, thermogravimetric analysis, and single-crystal X-ray diffraction (2a, 4a, 4b, 5a, 7a, and 7b). The complexes were tested for antiproliferative activity in vitro in three human cancer cell lines, namely, CH1 (ovarian carcinoma), SW480 (colon adenocarcinoma), and A549 (non-small-cell lung cancer), yielding IC(50) values in the submicromolar or low micromolar range.  相似文献   
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