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1.
The authors demonstrate 10 Gbit/s optical soliton transmission in a recirculating loop through the use of a monolithically integrated MQW-DFB-LD/MQW-EA modulator light source. The timing jitter due to the Gordon-Haus effect is successfully reduced by the optical bandpass filters conventionally used in the cascaded EDFAs to avoid the accumulation of amplified spontaneous emission. The transmission distance of 7200 km is achieved at a bit error rate of 10-9  相似文献   
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Cell death was analyzed in neurulating mouse embryos after in vivo doses of 2-methoxyethanol (2-ME) that produce anterior neural tube defects. Characterization of 2-ME-induced cell death was performed by evaluating: (1) vital fluorochrome staining in whole embryos applying confocal laser scanning microscopy; (2) characteristics of cell debris in conventional histological sections revealed by light microscopy; and (3) Apoptag in situ immunohistochemical staining for apoptosis using light microscopy. Methods for quantification of cell death identified by these three techniques were explored using computerized image analysis. Physiological cell death in control embryos primarily occurred in the neural crest region during neural fold elevation. Embryos exposed to 2-ME had expanded areas of cell death in the neural crest and also new areas of cell death in medial regions of the anterior neural tube. Both physiological and 2-ME-induced embryonic cell death had morphological, immunohistochemical, and fluorochrome staining characteristics of apoptosis. When fluorescence data from confocal microscopic analysis of vital fluorochrome-stained embryos were analyzed, a dose-dependent increase was found in embryos exposed to 2-ME. Similar results were obtained when cell death was analyzed in either conventional histological sections or sections prepared for immunohistochemical detection of apoptosis. The cell death data obtained in this study correlate with previously observed near-term malformation rates, suggesting that a quantitative relationship exists between 2-ME-induced embryonic cell death and neural tube defects.  相似文献   
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We investigated whether a chemical assay by high-performance liquid chromatography (HPLC) as an alternative to the complicated and time-consuming bioassay for CS23 mutein of recombinant human basic fibroblast growth factor (rhbFGF-CS23) using the fetal bovine heart endothelial cell line ATCC CRL 1395. Physically, chemically or enzymatically denatured rhbFGF-CS23 was subjected to heparin affinity (HA)-HPLC and the bioassay. Good agreement was observed between the results obtained by these two methods. Moreover, HA-HPLC gave much more reproducible results (RSD = 1.9%, n = 6) than the bioassay (RSD = 7.4%, n = 18). HA-HPLC is therefore a simple, accurate and reproducible alternative to the bioassay for quality control and stability studies for rhbFGF-CS23 preparations. HA-HPLC is also considered to be applicable to assays for FGFs which have heparin affinity and biological activity similar to those of the CS23 mutein.  相似文献   
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Taking into consideration the knock-on cascade mechanism and the free volume theory, the cooling condition dependentR s (ion etching rate) is investigated for a liquid-quenched Fe-10at%Si-15at%B alloy glass. A highR s is found in a slow cooled glass.  相似文献   
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Camcorders have been developed to be compact with high performance. Latest advancement of key technologies and devices such as digital signal processing LSI, six-layer printed circuit board with micro chips, high-speed power lens with linear motor, 103 K pixels 0.7-in LCD electronic viewfinder, and high-energy Li-ion battery are described. High-band format is also explained  相似文献   
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We examined the thrombolytic properties of a novel modified human tissue plasminogen activator (PA) (E6010), in which cysteine 84 is replaced by serine, and which has a prolonged biologic half-life (t1/2). We compared the thrombolytic efficacy of continuous intracoronary (i.c.) infusion of E6010 with that of recombinant human tissue PA (rt-PA) in a canine model with copper coil-induced 1-h-old coronary artery thrombi and also compared the relation between thrombolytic efficacy and plasma clearance represented by pharmacokinetic parameters of i.c.-infused E6010 and rt-PA. Sixty-minute E6010 and rt-PA i.c. infusions were compared. The thrombolytic effects of i.c.-infused E6010 and rt-PA, represented by time to reperfusion (TR), reperfusion rate at 60 min (RR), and reocclusion rates at 60 min after reperfusion (OR) were as follows. E6010: Dose 0.06, 0.15, 0.3 (mg/kg/h); TR 25 +/- 10, 15 +/- 10, 13 +/- 5 (min); RR 100, 100, 100 (%); and OR 0, 0, 17 (%), respectively. Recombinant t-PA: Dose 0.06, 0.15, 0.3 (mg/kg/h); TR 47 +/- 12, 18 +/- 17, 14 +/- 4 (min); RR 50, 75, 100 (%); and OR 100, 33, 33 (%), respectively. These findings indicate that E6010 has more potent thrombolytic activity than rt-PA.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Miscibility has been investigated in blends of poly(butylene succinate) (PBSU) and poly(vinyl phenol) (PVPh) by differential scanning calorimetry in this work. PBSU is miscible with PVPh as shown by the existence of single composition dependent glass transition temperature over the entire composition range. In addition, the polymer–polymer interaction parameter, obtained from the melting depression of PBSU using the Nishi–Wang equation, is composition dependent, and its value is always negative. This indicates that PBSU/PVPh blends are thermodynamically miscible in the melt. Preliminary morphology study of PBSU/PVPh blends was also studied by optical microscopy (OM). OM experiments show the spherulites of PBSU become larger with the PVPh content, indicative of a decrease in the nucleation density, and the coarseness of PBSU spherulites increases too with increasing the PVPh content in the blends.  相似文献   
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