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21.
An investigation into the transmission characteristics of erbium-doped fiber amplifiers for use in optical AM frequency division multiplexing (FDM) video distribution systems is reported. The output signal power and noise characteristics of erbium-doped fibers were measured for different fiber lengths and different pump powers. The experimental results confirm that there exists an optimum amplifier design which gives the maximum distribution number when the pump power and the required video quality are given  相似文献   
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This study estimated the dietary intakes of 25 pairs of Japanese children and their parents to 12 toxic and essential trace elements using 7-day duplicate diet composites. The estimated intakes of lead (children = 5.34 microg day-1, adults = 6.74 microg day-1) and tin (162 and 152 microg day-1) were below tolerable limits, but large difference in aluminium intakes (7.32 and 12.1 mg day-1) among the subjects warranted further investigations. Intakes of cadmium in both children and adults (13.2 and 15.9 microg day-1) were high, but a low uranium (U) intake was observed (0.593 and 0.587 microg day-1). Intakes of copper (567 and 784 microg day-1), manganese (1.56 and 2.72 mg day-1), zinc (4.93 and 6.75 mg day-1), and molybdenum (103 and 131 microg day-1) were close to the recommended values. Concentrations of chromium, nickel and selenium were lower than the detection limits in most cases.  相似文献   
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This paper proposes a high-level fluctuation tolerant optical receiver for optical packet switches and WDM cross-connects. We describe the tolerance of an experimental receiver to packet-level fluctuation and coherent crosstalk. The sensitivity of the experimental receiver was -26.9 dBm for the packet receiver configuration and -32.7 dBm for the WDM cross-connect configuration at the bit rate of 10 Gb/s. In the setup for level-fluctuating packet reception, the power-penalties of 1.1 and 4.6 dB were observed with 6 and 10 dB of fluctuation, respectively. As a WDM cross-connect, the sensitivity penalties of the receiver under the coherent crosstalk powers of -15 and -12 dB were 2.5 and 6.5 dB, respectively  相似文献   
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The aim of this study was to evaluate the yield of nucleated cells in bone marrow harvested by means of Downs' Islam aspiration needles with or without side-holes. Twenty marrow donors for HLA identical sibling transplants were studied. Bone marrow nucleated cells were harvested 50 ml in the right iliac bone with a Downs' Islam aspiration needle with or without side-holes and 50 ml in the left with another kind of needle by means of 5 ml aspirations in each donor. There were no significant difference between the number of nucleated cells by means of Downs' Islam aspiration needles with and without side-holes by cross-over analysis. All nucleated cell counts were 33.06 +/- 12.93 x 10(3)/microliter (mean +/- standard deviation) by means of the needle with side-holes and 32.90 +/- 15.25 x 10(3)/microliter by means of the needle without side-holes. The Downs' Islam aspiration needle without side-holes seems to be better in bone marrow harvest from normal volunteers than that with side-holes, because the former may be stronger than the latter.  相似文献   
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Previously we isolated a new trypsin-like enzyme designated human airway trypsin-like protease (HAT) from human sputum. In this study, we examined in vitro whether HAT was related to the prevention of fibrin deposition in the airway lumen by cleaving fibrinogen. In mucoid sputum samples from patients with chronic airway diseases, the concentration of fibrinogen, as measured by ELISA, was in the range of 2-20 micrograms/ml, and trypsin-like activity, as measured by spectrofluorometry was in the range of 10-50 milliunits (mU)/ml. We showed by gel filtration that the trypsin-like activity of mucoid sputum was mainly due to HAT. We examined the effects of HAT on human fibrinogen at pH 7.4 and 8.6. Fibrinogen was used at concentrations of 4-2,000 micrograms/ml and HAT purified from sputum at concentrations of 0.6-10 mU/ml. As shown by SDS-polyacrylamide gel electrophoresis, HAT cleaved fibrinogen, especially its alpha-chain, regardless of the concentration of fibrinogen. Pretreatment of fibrinogen with HAT resulted in a decrease or complete loss of its thrombin-induced clotting capacity, depending on the duration of pretreatment with HAT and the concentration of HAT. From these results we postulated that HAT may participate in the anticoagulation process within the airway, especially at the level of the mucous membrane, by cleaving fibrinogen transported from the blood stream.  相似文献   
28.
We propose an optical parallel information processing technique adopting synthesis of the optical coherence function by using direct frequency modulation of a laser diode. The optical coherence function having a delta-function-like shape can be synthesized by modulating the laser frequency with an appropriate waveform. In this optical parallel information processing system, selective extraction of two-dimensional information from a three-dimensional semitransparent object, and other operations between two-dimensional information, can be carried out. This manner has no mechanical moving part, and there is no need for calculation by combining with holographic method. In this paper, the method to synthesize the optical coherence function is studied in detail. The manner to improve the suppression ratio of unnecessary subpeaks in the delta-function-like coherence function is studied both in theory and experiments. Moreover, notch-shaped optical coherence function is also studied. Selective extraction and selective masking of a two-dimensional information from a three-dimensional object was successfully performed in basic experiments  相似文献   
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We present a case of undifferentiated pancreatic cancer associated with humoral hypercalcemia of malignancy (HHM) in which parathyroid hormone-related protein (PTH-rP) is identified as the causative factor of hypercalcemia. A 61-year-old man was hospitalized with right hypochondralgia. Ultrasound examination and computed tomography demonstrated a large mass in the pancreatic head with liver metastases. Biopsy of the pancreatic tumor demonstrated undifferentiated carcinoma. Serum calcium level and PTH-rP were elevated. Bone scan with technetium-99 demonstrated no accumulation in the bones. Immunohistochemical staining for PTH-rP was weakly positive in the tumor cells. We considered that PTH-rP was the causative factor of HHM in this case from laboratory data and immunohistochemical findings. This rare case was successfully treated with pamidronate disodium, which is a type of bisphosphonate derivative. We compared this case with previously reported cases.  相似文献   
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