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31.
The fruit quality parameters and antioxidant capacity (ferric reducing antioxidant power, FRAP) and total phenolic content (TPC) were determined in 27 apricot cultivars and hybrids of diverse origins. Twenty one- to 35-fold variations were measured among FRAP and TPC values. Besides genotype, harvest year also contributed significantly (P≤0.05) to the variations of TPC presumably due to the climatic differences between years. A subset of genotypes (15) was also analyzed for their antiradical activities (2,2'-diphenyl-1-picrylhydrazyl, DPPH; total radical-scavenging activity, TRSA; water-soluble antioxidant capacity, ACW; and lipid-soluble antioxidant capacity, ACL), and vitamin C contents as well as color indices (CIE H°, L*, and chroma). The hybrid "Preventa" had outstanding FRAP (>10.4 mmol ascorbic acid/L), DPPH (74.45%), TRSA (0.002%), ACW (33587.5 nmol AA/L) and ACL (78.65 nmol Trolox/L), TPC (>2890.0 mg gallic acid/L), and vitamin C (16.17 mg/100 g FW) levels and an average carotenoid content estimated from the hue angle (66.99°). Most antioxidant and antiradical activities correlated significantly except for TRSA; the closest correlation was observed between FRAP and ACW (r=0.952). Only TRSA showed significant correlations with color indices, H° and chroma, suggesting TRSA measures at least a fraction of the antioxidant capacity attributable to apricot carotenoids.  相似文献   
32.
We investigated the ability of six different pooled human immunoglobulin (PHIG) preparations to inhibit the binding of anti-myeloperoxidase (MPO) antibodies to MPO. All six PHIG preparations inhibited the binding of anti-MPO antibodies from six sera to MPO in a concentration-dependent manner in the concentration range 0.016-10 mg/ml. There was considerable variation in the ability of each PHIG preparation to inhibit the binding of anti-MPO antibody in a given serum. Further differences were seen in the ability of a given PHIG to inhibit anti-MPO binding in different sera. F(ab')2 fragments from two PHIG preparations also inhibited in a concentration-dependent manner anti-MPO binding to MPO in all six sera in the concentration range 0.002-2.65 mg/ml, with a maximum inhibition of 42%. Little inhibition was seen with F(ab')2 of normal human IgG from individual donors (1.8-12.2% at the maximum concentration of 2 mg/ml). F(ab')2 fragments from three anti-MPO containing sera and two affinity-purified anti-MPO antibodies were eluted by affinity chromatography from Sepharose-bound PHIG F(ab')2 and showed anti-MPO antibody activity. We have shown that PHIG and F(ab')2 fragments of PHIG inhibit anti-MPO binding to MPO, and further that F(ab')2 fragments of PHIG bind to F(ab')2 fragments of anti-MPO antibodies. These observations indicate binding between the variable regions of PHIG and the antigen binding site of anti-MPO antibodies, and are consistent with an anti-idiotypic reaction. The variability seen in the inhibitory effect of the different PHIG preparations in anti-MPO-positive sera implies differences in their anti-idiotype content, while the variability of the inhibitory effect of a particular PHIG preparation between different sera suggests heterogeneity in the idiotypic repertoire of anti-MPO antibodies. Such variations in the inhibitory effect of different PHIG preparations on antibody binding may be an important determinant of their therapeutic effect.  相似文献   
33.
A new index is proposed to estimate the variance of the differentiated heart rate (RR) time series from its truncated histogram. The index is more robust to artifacts than the standard deviation of the differentiated RR time series (rMSDD) and, unlike the pNN50, does not saturate for very high or very low heart rate variability.  相似文献   
34.
The effect of standardized forced diuresis (SFD) on the serum and urinary electrolyte levels was investigated in 10 cases of severe self-poisoning with hypnotic drugs. Diuresis was initiated by furosemide and maintained at an hourly urinary ouput of 2 litres. Fluid and electrolyte substitution was carried out with a standardized electrolyte solution. Initiation and termination of the SFD was performed abruptly. The mean values of sodium, potassium, chloride and phosphorus in the urine varied widely at the beginning of the SFD, while the calcium and magnesium values varied only slightly. During SFD, urinary stabilization occured at a particular ionogram, in correlation to the electrolyte concentrations in the infusion fluid and with only minimal individual variation. Owing to this satisfactory correlation, none of the patients developed signs of electrolyte disturbances, so that no correction of the infusion constitution was necessary. The abrupt termination of the SFD prevented electrolyte disturbances in the recovery phase.  相似文献   
35.
Fully differential amplifiers yield large differential gains and also high common mode rejection ratio (CMRR), provided they do not include any unmatched grounded component. In biopotential measurements, however, the admissible gain of amplification stages located before dc suppression is usually limited by electrode offset voltage, which can saturate amplifier outputs. The standard solution is to first convert the differential input voltage to a single-ended voltage and then implement any other required functions, such as dc suppression and dc level restoring. This approach, however, yields a limited CMRR and may result in a relatively large equivalent input noise. This paper describes a novel fully differential biopotential amplifier based on a fully differential dc-suppression circuit that does not rely on any matched passive components, yet provides large CMRR and fast recovery from dc level transients. The proposed solution is particularly convenient for low supply voltage systems. An example implementation, based on standard low-power op amps and a single 5-V power supply, accepts input offset voltages up to +/-500 mV, yields a CMRR of 102 dB at 50 Hz, and provides, in accordance with the AAMI EC38 standard, a reset behavior for recovering from overloads or artifacts.  相似文献   
36.
We focus on the investigation of multilayer recording in microholographic data storage. We have developed a numerical model for calculating the electromagnetic scattering from thick microholographic gratings using the Born approximation and the direct volume integral. The signal-to-noise ratio and bit error rate were calculated to estimate the noise arising from interlayer and interhologram cross talk. Measurements were done to prove the validity of the model. The results of our calculations and the measurements show good agreement. We present the application of the model to the investigation of confocal filtering at the image plane and to the evaluation of positioning and wavelength tolerances.  相似文献   
37.
The development of systems for targeted delivery of Sorafenib in unresectable hepatocellular carcinoma to reduce the systemic toxicity is a challenge. In our article, we successfully prepared core-shell microcapsules based on bovine serum albumin gel with polyelectrolyte complex multilayer shell of polysaccharides with opposite charges, hyaluronic acid, and chitosan, encapsulating Sorafenib, as targeting delivery system for improved hepatocellular carcinoma therapy. A bovine serum albumin gel core was formed by a method based on a sacrificial CaCO3 template, followed by the multilayer shell build-up of Ca2+ cross-linked hyaluronic acid hydrogel, and subsequently alternating multilayers of the polyelectrolyte complex formed between hyaluronic acid and chitosan. The following techniques: Fourier-transform infrared and UV–Vis spectroscopy, X-ray diffraction, differential scanning calorimetry, confocal laser scanning microscopy, atomic force microscopy, and scanning electron microscopy were used for the physicochemical characterization. These tests revealed the spherical shape of core-shell type, the micro-size, as well as the composition of microcapsules after their synthesis and proved the successful encapsulation and release of the drug. The promising results regarding encapsulation efficiency, Sorafenib release profile and cytotoxicity on HepG2 and mesenchymal stem cells, recommend Sorafenib loaded microcapsules as suitable targeted drug carriers for further in vivo studies for hepatocellular carcinoma therapy.  相似文献   
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39.
Two cases of poisoning with moclobemide are presented. Moclobemide is a reversible inhibitor of the monoamine oxidase type A (RIMA). Intoxication with moclobemide is according to previously published case stories benign. Both patients described presented severe symptoms, such as convulsions, coma, muscle rigidity and respiratory failure. One of the patients, a 37-year-old woman, also suffered cardiovascular collapse and elevated body temperature (more than 41.9 degrees C), which was treated successfully with dantrolene and norepinephrine. The symptoms match the diagnostic criteria for serotonin syndrome. The possible reasons why the two patients suffered life-threatening complications and the treatment of serotonin syndrome are discussed.  相似文献   
40.
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