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41.
This paper describes a low‐cost version of a full‐duplex optical fibre analogue/digital data transmission link whose practical implementation is simplified by using a pair of laser diodes, each having a built‐in photodiode for monitoring the laser output power, and its application to vibration test data transmission. The transmission link sends digital data of up to 9600 bps in one direction, and analogue data of DC to 100 kHz and image data specified by an NTSC colour video signal in the opposite direction, all at the same time through one GI optical fibre. Being simple in configuration and stable against noise, this type of link has a variety of applications within factory, home and offices. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
42.
PURPOSE: The purpose of this study was to analyze the effects of lesion site and epithelial keratinization on the morphologic characteristics of odontogenic cysts and clarify determinate factors for cyst morphology. MATERIAL AND METHODS: Computed tomographic images of 92 odontogenic cysts were analyzed: 31 primordial, 31 dentigerous and 30 radicular. Thirty-four cysts were located in the maxilla (6 primordial, 10 dentigerous, and 18 radicular) and 58 in the mandible (25 primordial, 21 dentigerous, and 12 radicular). Histologically, 31 cysts showed epithelial keratinization (18 primordial and 13 dentigerous). No keratinization was seen in radicular cysts. The morphologic features of cysts were assessed by measuring long length parallel to dental arch and short length vertical to it and calculating the long/short ratio. In addition, the computed tomography pattern of the cyst was classified into unilocular, lobulated, and multilocular patterns. Appearance of the sclerotic rim and surrounding cortex were classified into three and four patterns respectively to evaluate the developmental features of the cyst. RESULTS: As a whole, the long length of the primordial cysts was statistically larger than the other two cyst groups and resulted in a larger long/short ratio. Statistical differences of CT pattern were also seen among cyst groups. There was no preference in any cyst group for the appearance of the sclerotic rim and cortex. There were statistical differences between maxilla and mandible in short axis and long/short ratio. The maxillary cysts generally showed round shapes irrespective of their histologic characteristics. A multilocular pattern was more frequent in the keratinized group of mandibular primordial cysts. In dentigerous cysts, a multilocular pattern was seen only in the keratinized group and the long/short ratio was statistically larger; cyst shape was elliptical along the long axis. CONCLUSION: Our results demonstrated morphologic differences of odontogenic cysts caused by lesion site and keratinization. The dentigerous cyst with predominant keratinization should be included in the primordial cyst (odontogenic keratocyst) group.  相似文献   
43.
A female child with dicentric translocation between chromosome 9 and chromosome 18 presented non-specific minor anomalies with laryngomalacia. Chromosomal analyses were performed by the G-banding method and a fluorescence in situ hybridization (FISH) technique with a specific probe for the centromeric region of chromosome 18 and the painting probe for the chromosomes 9 and 18. Her full karyotype was confirmed as 45,XX,tdic(9;18)(p24;p11). This is the first case of dicentric translocation between chromosomes 9 and 18. The FISH technique is an important tool in chromosome diagnostics.  相似文献   
44.
Several kinds of fusion proteins between human aldolases A andB were prepared by recombinant DNA technology and their enzymicproperties were examined. AB chimeras, which have aldolase Aat the N-terminal region and aldolase B at the C-terminal region,were scarcely obtained, while BA chimeras were abundant (Kitajimaet al., (1990), J. Biol. Chem., 265, 17493-17498). All the BABchimeras, aldolase A fragments inserted in aldolase B, showedactivity assignable to aldolase B type, which imply an essentialrole of Tyr residue at the C-terminus of aldolase A in the bindingof fructose-l,6-bisphosphate (Fni-1,6-P2). BAB chimeras alsoshowed reactivity to effectors such as fructose-2,6-bisphosphate(Fru-2,6-P2) and pyridoxal 5-phosphate (PLP), in a similar mannerto aldolase B. BAB108 has a similarity to the BA108 chimera,but acts differently from other BAB chimeras, suggesting thatits structure around active site looks like that of aldolaseA  相似文献   
45.
A conversion efficiency of 12.65% was obtained at AM-1.5, 100 mW/cm2 for a single p-i-n junction amorphous-Si solar cell of 1.05 cm2, with a glass/SnO2/p-i-n/back-electrode structure. The solar cell had a short-circuit current of 19.13 mA/cm2, an open-circuit voltage of 0.885 V, and a fill factor of 74.7%. The reason why the efficiency of the produced solar cell was enhanced by hot-annealing treatment is considered to be due to the reduction of the minute leaks caused by the pinhole treatment and the reduction of the number of pinholes by reverse-bias annealing treatment. It is believed that because of the minute irregularities on the surface of SnO2, the diffuse light in the solar cell increased the effective optical length in the i layer. Therefore the collection efficiency in the long-wavelength region was enhanced  相似文献   
46.
Preoperative evaluation of the operative indication of hepatic resection using the parameters obtained by 99mTc-GSA scintigraphy has been done. In particular, the accurate evaluation of the postoperative hepatic functional reserve essentially depends on these parameters. In the present study, a preoperative evaluation of postoperative hepatic functional reserve using 99mTc-GSA scintigraphy was performed in our operated cases retrospectively. PATIENTS AND METHODS: Thirty-eight patients who underwent hepatic resection were studied on 99mTc-GSA scintigraphy before and after operation. These patients were divided into two groups. Group A; had no postoperative complications (n = 31). Group B; had some postoperative complications (n = 7). Preoperative parameters of 99mTc-GSA liver scintigraphy (HH15, LU15) were calculated from the activities of liver and cardiac ROIs at 5 and 15 minutes after injection. The resection ratio (RR) was obtained by comparing the liver volumes which were calculated from the pre- and postoperative SPECT studies. The resectability indices (Res) were as follows: Res (LU15) = LU15 x (100-RR(%)/100, Res (HH15) = (1/HH15) x (100-RR (%)/100. RESULTS: There were statistically significant differences in the distribution of Res between A and B groups (p = 0.002, Mann-Whitney test). The values of Res, of which half of patients have complication, were 1.10 (Res (HH15)) and 16.4 (Res (LU15)). CONCLUSION: The resectability indices using 99mTc-GSA liver scintigraphy are useful for the preoperative evaluation of the limitation of hepatic resection.  相似文献   
47.
Right facial nerve palsy in a 58-year-old woman was due to sarcoidosis demonstrated by Gd-DTPA enhanced MRI. Abnormal enhancement of the right VIIth cranial nerve in the distal internal acoustic canal was seen on MRI. The enhancing lesion was smaller after 1 month of prednisolone 50 mg day-1. This is the first report on facial nerve involvement in neurosarcoidosis examined by Gd-DTPA enhanced MRI. The use of Gd-DTPA enhanced MRI with thin slicing, e.g. 3 mm slice thickness and 1 mm interslice gap, is effective in detecting small extramedullary lesions.  相似文献   
48.
We propose a new 2-port SRAM with a single read bit line (SRBL) eight transistors (8 T) memory cell for a 45 nm system-on-a-chip (SoC). Access time tends to be slower as a fabrication is scaled down because of threshold voltage (Vt) random variations. A divided read bit line scheme with shared local amplifier (DBSA) realizes fast access time without increasing area penalty. We also show an additional important issue of a simultaneous read and write (R/W) access at the same row by using DBSA with the SRBL-8T cell. A rise of the storage node causes misreading. A read end detecting replica circuit (RER) and a local read bit line dummy capacitance (LDC) are introduced to solve this issue. A 128 bit lines - 512 word lines 64 kb 2-port SRAM macro using these schemes was fabricated by a 45 nm bulk CMOS low-standby-power (LSTP) CMOS process technology [1]. The memory cell size is 0.597 mum2. This 2-port SRAM macro achieves 7 times faster access time without misreading.  相似文献   
49.
Engineering liver tissue constructs with sufficient cell mass for transplantation implies culturing large numbers of hepatocytes in a reduced volume; however, providing sufficient oxygen to dense cell cultures is still not feasible using only conventional culture medium. Liposome-encapsulated hemoglobin (LEH), an oxygen-carrying blood substitute originally designed for short-term perfusion, may be a good candidate as an oxygen carrier to cultured liver cells. In this study, we investigated the feasibility of maintaining long term hepatocyte cultures using LEH. Primary fetal and adult rat liver cells were directly exposed to LEH for 6 to 14 days in static culture or in a perfused flat plate bioreactor. The functions and viability of adult rat hepatocytes exposed to LEH were not adversely affected in static monolayer culture and were even improved in the bioreactor. However, some cytotoxicity of LEH was observed with fetal rat liver cells after 4 days of culture. LEH, though a suitable oxygen carrier for long-term culture of mature hepatocytes, is not suitable in its present form for perfusing fetal hepatocyte cultures in direct contact with the liposomes; either the LEH will have to be made less toxic or a more sophisticated bioreactor that prevents the direct contact between hepatocytes and perfusates will have to be designed if fetal cells are to be used for liver tissue engineering.  相似文献   
50.
Glycosaminoglycans (GAGs) play important roles in cell adhesion and growth, maintenance of extracellular matrix (ECM) integrity, and signal transduction. To fully understand the biological functions of GAGs, there is a growing need for sensitive, rapid, and quantitative analysis of GAGs. The present work describes a novel analytical technique that enables high throughput cellular/tissue glycosaminoglycomics for all three families of uronic acid-containing GAGs, hyaluronan (HA), chondroitin sulfate (CS)/dermatan sulfate (DS), and heparan sulfate (HS). A one-pot purification and labeling procedure for GAG Δ-disaccharides was established by chemo-selective ligation of disaccharides onto high density hydrazide beads (glycoblotting) and subsequent labeling by fluorescence. The 17 most common disaccharides (eight comprising HS, eight CS/DS, and one comprising HA) could be separated with a single chromatography for the first time by employing a zwitter-ionic type of hydrophilic-interaction chromatography column. These novel analytical techniques were able to precisely characterize the glycosaminoglycome in various cell types including embryonal carcinoma cells and ocular epithelial tissues (cornea, conjunctiva, and limbus).  相似文献   
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