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71.
Temperature sensitive poly(N-isopropylacrylamide) (PIPAAM) was incorporated into hepatocyte-recognizable poly[N-p-vinylbenzyl-O-beta-D-galactopyranosyl-(1 --> 4)-D-gluconamide] (PVLA) for thermal modulating of hepatocyte attachment. The copolymer, poly(N-isopropylacrylamide-co-N-p-vinylbenzyl-O-beta-D-galactopyranosyl-(1 --> 4)-D-gluconamide) (abbreviated as [P(IPAAM-co-VLA)] (PIPAAM/PVLA = 9/1 in mol%) exhibited lower critical solution temperature (LCST) at 34 degrees C and also showed very good hepatocytes-recognizablility through the specific interaction between asialoglycoprotein receptors on the cell surfaces and galactose moiety of the copolymer. The cells attached on this copolymer were easily detached by lowering the temperature below the LCST of the copolymer. Morphological damage of the detached cell was not observed.  相似文献   
72.
The purpose of this study was to determine whether ES-242-1, a novel N-methyl-D-aspartate (NMDA) receptor antagonist of microbial origin, has anti-nociception at the spinal level and to evaluate how its anti-nociceptive effect differs from that of MK-801, a non-competitive NMDA receptor antagonist. Agents were injected intrathecally (0.1, 1.0 and 10 microg) through a previously implanted PE tube in rats. Formalin (2%, 100 microl) was injected subcutaneously into the left hindpaw 15 min after each antagonist administration. Licking time as a nociceptive behavior was measured in three stages after formalin-injection, such as early phase (0-9 min), late first phase (10-29 min) and late second phase (30-60 min). In the early phase, the largest dose of ES-242-1 significantly decreased total licking time, although MK-801 did not show any significant reduction. With the treatment of 1.0 and 10 microg MK-801, total licking time in both late first and second phases was significantly suppressed, although the smallest dose (0.1 microg) of ES-242-1 showed a significant reduction in the late second phase. These results indicate that ES-242-1 is highly effective against tonic pain, such as inflammatory pain.  相似文献   
73.
The quantitation of human papillomavirus DNA isolated from warts by chromato-scanning (fluorescence mode) photographs of ethidium bromide-stained agarose gels is described. Excitation at 200 nm (with a cutoff filter at 400 nm) generates fluorescence from the white portion of the printing paper. The fluorescent intensity correlated with the quantities of DNA in the band of interest. The amounts of DNA were determined using calibration curves of approximately the same size as lambda phage DNA fragments. This general method of quantification is applicable to photographs of other types of polynucleotides capable of being separated and stained in a gel medium.  相似文献   
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A 68-year-old male with Paget's disease of the esophagus is reported. The underlying primary esophageal carcinoma was diagnosed as adenosquamous cell carcinoma on the basis of the presence of both adenocarcinoma and epidermoid carcinoma components. There was invasive growth of clear Paget's cells in the esophageal epithelium. Mucin histochemistry disclosed common characteristics of mucin between Paget's cells and adenosquamous cell carcinoma. It was histochemically confirmed that the existence of mucin was a general feature of extramammary Paget's disease. In 13 control esophageal carcinomas including three with adenocarcinomatous elements, Paget's cells were not found in the epithelium. To date only one case of Paget's disease of the esophagus has been described in the literature.  相似文献   
77.
We compared morphological and morphometric data on various motor neurons in the human pyramidal system using the modified Klüver-Barrera staining method with extremely minimized shrinkage ratio and an image-analyzer. We classified motor neurons in the human pyramidal system into three groups according to the measurement data. This report may be of interest to better understand the process of nerve conduction in the human pyramidal system.  相似文献   
78.
Monomers containing several octadecyl groups, e.g., 2-isopropenyl-4,6-bis(octadecylamino)-1,3,5-triazine ( 2 ), 2-dioctadecylamino-4-isopropenyl-6-octadecylamino-1,3,5-triazine ( 3 ) and 2,4-bis(dioctadecylamino)-6-isopropenly-1,3,5-triazine ( 4 ) were prepared by the alkylation reaction of 2,4-diamino-6-isopropenyl-1,3,5-triazine ( 1 ) with 1-bromooctadecane in the presence of sodium hydride. In the free-radical homopolymerization of these monomers, the polymer yield of 3 was lower than that of 2 due to a decrease in the ceiling temperature, and the polymerization of 4 did not proceed. Copolymerizations of these monomers with styrene or methyl methacrylate were carried out and the monomer reactivity ratios (r1 and r2) were determined. The monomer reactivity decreased with increasing the number of octadecyl groups in the monomers. Crystallinity of the octadecyl side chains in the resulting comb-like polymers was evaluated by differential scanning calorimetry.  相似文献   
79.
The objectives of this study were to evaluate the correlations of the volumes of the gray matter and white matter with age, and the correlations of the tissue probabilities of the gray matter and white matter with age and several cerebrovascular risk factors. We obtained magnetic resonance (MR) images of the brain and clinical information from 769 normal Japanese subjects. We processed the MR images automatically by correcting for inter-individual differences in brain size and shape, and by segmenting the MR images into the gray matter and white matter. Volumetry of the brain revealed a significant negative correlation between the gray matter volume and age, which was not observed between white matter volume and age. Voxel-based morphometry showed that age, systolic blood pressure, and alcohol drinking correlated with the regional tissue probabilities of the gray matter and white matter.  相似文献   
80.
The mechanisms of arterial hypotension following intravenous anesthetic induction agents are multifactorial. The purpose of this study was to evaluate and compare the effects of thiopental, propofol and etomidate on hemodynamics, sympathetic outflow and arterial baroreflex sensitivity using not only neuraxis-intact but also totally baro-denervated rabbits. A total of 60 rabbits was anesthetized with urethane, tracheotomized, and mechanically ventilated with oxygen in nitrogen (FiO2 0.5). The left renal sympathetic nerve was isolated and placed on a bipolar electrode to record renal sympathetic nerve activity (RSNA). Thirty animals underwent a surgical preparation of total baroreceptor denervation. Bolus injections of an anesthesia induction dose of thiopental 4 mg/kg and twice the induction dose of propofol 4 mg/kg significantly decreased RSNA to the same extent (19.4+/-6.7 and 19.7+/-5.2% reduction, mean +/- SEM) and mean arterial pressure (MAP) also to the same extent (19.5+/-4.6 and 22.1+/-3.1% reduction) in the neuraxis-intact animals. RSNA was increased (34.5+/-6%) without reduction of MAP by an induction dose of etomidate, 0.3 mg/kg. Sympathetic barosensitivity was attenuated even 10 min after thiopental at 4 mg/kg or propofol at 4 mg/kg (68% and 54% of control, respectively). Propofol at 2 mg/kg (induction dose) and etomidate at 0.6 mg/kg decreased RSNA and MAP only in the baro-denervated animals. It was found from the barosensitivity study that patients can be hemodynamically unstable even though blood pressure has returned to normal after thiopental and propofol administration. Data suggest that etomidate can even stimulate the sympathetic nervous system and increase sympathetic outflow. It was also clearly found from the baro-denervated animal study that thiopental was stronger than propofol in directly suppressing sympathetic outflow at the induction dose.  相似文献   
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