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21.
A laboratory-performance study was carried out to investigate factors affecting the reliability of the quantitative PCR method to analyze an approved genetically modified (GM) maize (Mon810 line). Test maize powdered samples were prepared as blind samples containing a high (assigned value; 5.45%) or low (assigned value; 0.35%) concentration of the Mon810 line. After confirmation of their homogeneity, they were provided to 27 laboratories participating in the collaborative study. The data were collected from all laboratories and statistically analyzed. Two laboratories, which used a Roche LightCycler (LC), reported significantly high test values. A further examination showed that the LC method is greatly affected by the equipment itself or PCR reagents, resulting in poor repeatability. On the other hand, some laboratories, which used ABI quantitative PCR equipment, reported erroneous test values. In these laboratories, the errors appeared to have been due to inadequate quality and/or yield of DNA. To identify factors affecting the test values, analysis of the measured values for the taxon-specific gene will be useful. Furthermore, the modified silica-gel membrane DNA extraction method made it possible to extract the required amounts of DNA more easily and in a shorter time than before.  相似文献   
22.
Analysis of rubusoside and related compounds in tenryocha extract sweetener   总被引:4,自引:0,他引:4  
The main and minor constituents of tenryocha extract product, a natural sweetener, were investigated as a part of an ongoing study to evaluate its quality and safety as a food additive. Four constituents, namely rubusoside, steviolmonoside, panicloside IV, and ent-16 alpha, 17-dihydroxykauran-19-oic acid, were isolated. The concentration of rubusoside, the main sweet constituent, was 8.65% in the tenryocha extract product. In addition, it was confirmed that the origin of the extract was the leaves of Rubus suavissimus S. Lee (Rosaseae), as determined by comparing TLC and HPLC profiles of the product and hot-water extract prepared from the leaves of R. suavissimus.  相似文献   
23.
In the present paper, a configuration of a sensor network system for monitoring the usage patterns of a house is proposed. The sensor network system has many active type radio-frequency identifications (RFIDs) as a network node. The RFID has advantages of low cost and low power consumption. Also the RFID can connect various sensors for measuring environment information, since having I/O port as external interface. Environment information is stored on a database through the RFID’s wireless radio communication function. The sensor types in this system are variety from slow changing information like temperature and humidity data to event notification like a human detection data. The paper will be described a acquisition procedure for various characteristic sensor data on the same sensor network. Also, the installation locations of the sensors are critical for highly accurate detection of the environmental conditions. Finally, based on the sensor data, capability of analysis of the usage pattern for a house will be discussed.  相似文献   
24.
We measured the coagulation and fibrinolytic parameters in patients with various angiopathies to clarify the usefulness of the parameters for the evaluation of vascular involvement. The study included 65 patients with cerebral thrombosis at the chronic stage, 47 diabetics with neuropathy associated with diabetic microangiopathy, 15 diabetics without neuropathy, and 16 patients with vasculitic neuropathy associated with collagen diseases. Control subjects were 45 patients with other neurological disorders without symptomatic angiopathies. In cerebral thrombosis at the chronic stage, the coagulation factor VIII (FVIII), von Willebrand factor (vWF), and platelet factor IV were elevated significantly as compared with age-matched controls. Diabetics with neuropathy showed significantly elevated FVIII and vWF in comparison with diabetics without neuropathy and controls. No significant difference in parameters concerning glucose metabolism was observed between the two groups of diabetics. These findings suggest that elevated activities of the coagulation parameters reflect not merely the abnormalities in glucose metabolism but also the presence of microangiopathy which causes diabetic neuropathy. The patients with vasculitic neuropathy exhibited significantly elevated FVIII, vWF and fibrin/fibrinogen degradation products (FDP). The present study demonstrated that FVIII and vWF are useful parameters for the evaluation of the extent of vascular involvement in angiopathies of different etiologies. It is important for the treatment of patients with the angiopathies, to monitor the coagulation parameters which reflect vascular involvement in addition to parameters for the disease activity.  相似文献   
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Nishimura K  Yamakawa T 《Lipids》1968,3(3):262-266
A small amount of cerebroside containing glucose (glucosyl ceramide) was isolated from bovine brain by Florisil column chromatography and thin-layer chromatography. The fatty acids of the glucosyl ceramide were palmitic and stearic acids; small amounts of oleic and linoleic acids were present. Rat brain tissue slices, incubated with U-14C-glucose, incorporated more radioacivity into glucosyl ceramide than into galactosyl ceramide. From these results the possible metabolic significance of the brain glucosyl ceramide in ganglioside metabolism is discussed.  相似文献   
28.
Taketomi T  Yamakawa T 《Lipids》1966,1(1):31-40
Erythro-sphingosine was obtained from sphingomyelin by alkaline hydrolysis. N-p-nitrobenzoyl-sphingosine, N-p-aminobenzoyl-dihydrosphingosine and dihydrosphingosine-protein were synthesized. It was found that dihydrosphingosine-protein can produce a specific antibody which can be detected by the complement fixation test and by Ouchterlony's double diffusion method in agar. The determining factor of dihydrosphingosine may be due to the hydroxy groups at C1 and C3. In the course of experimental allergic encephalomyelitis, the cross-reactivity of rabbit antisera against spinal cord, and with psychosine-protein in particular, was observed by the complement fixation test and by the Arthus reaction. Presented at the Prof. Ernst Klenk Symposium on Glycolipids and the Nervous System, AOCS Meeting, Houston, April 1965.  相似文献   
29.
Headspace GC using the standard addition method has been developed for the simultaneous determination of organic solvents in natural flavorings. The procedure can be outlined as follows: an aliquot of the sample is transferred to a 10 mL vial. To each vial, a DMSO solution containing solvents at different concentrations is added as the standard solution. The vials are kept at 50 degrees C (for automatic injection) or 40 degrees C (for hand-operated injection) for 40 minutes. One mL of the vapor phase in each vial is injected into a gas chromatograph equipped with an Aquatic-2 column (0.25 mm i.d. x 60 m). To evaluate this method, we conducted a performance study in collaboration with 10 laboratories, using ginger oleoresin. We analyzed 6 solvents (methanol, 2-propanol, acetone, dichloromethane, hexane, and 1,1,2-trichloroethene) for which the maximum residue limits are established in Japan's Specifications and Standards for Food Additives. Methanol and acetone existed in the ginger oleoresin, so only the other that four kinds of solvents were added to it. Eight of the laboratories used automatic injection, while the remaining two used hand-operated injection. Statistical analyses were conducted on the data obtained from the 8 laboratories. Repeatability standard deviations (RSDr) ranged from 4.3 to 11.4%, and reproducibility standard deviations (RSDR) ranged from 8.4 to 19.0%.  相似文献   
30.
Nonresonant microwave absorption (NMA) measurements were carried out at liquid-nitrogen temperature on a high quality Bi2212 single crystal, as a function of microwave power in three mutual orientations of crystal ab plane, dc field (Hdc), and microwave magnetic field (Hw). NMA line shapes in Bi2212 crystal are complicated with a narrow peak (P1 peak) located near zero field, followed by a much broader second peak (P2 peak) in the particular orientations. More excitingly, we show that the P2 peak qualitatively evolves as a function of microwave power in the orientation of Hdc ab plane, plane, and Hdc Hw. In this configuration, as the microwave power is progressively increased, the broad P2 peak first gets smeared off and then a multiple peak structure appears, which develops into another narrower second peak (Ps-peak) at high enough microwave powers. In the orientation of plane, Hw ab plane, and Hdc Hw, we report for the first time the appearance and disappearance of a new second peak (P2-like peak) as a function of microwave power.  相似文献   
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