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81.
Fundamental morphological changes in human olivary hypertrophy. 总被引:1,自引:0,他引:1
Morphological features of neurons in human inferior olivary nuclei were studied in 6 autopsied patients with dentato-olivary pathway lesions, who had survived for between 6 days and 15 months. Central chromatolysis-like neuronal enlargements were already present in the acute cases. Electron microscopy revealed round, homogeneous and electron-dense granules, varying in diameter from 0.15 micron to 2.5 microns, occurring frequently within the rough endoplasmic reticulum (ER) in the chromatolytic neurons of all 6 patients. No similar granules were observed in 6 controls. The vacuoles were due to dilatation of the rough ER, and often contained floccular materials. Neurofilamentous hyperplasia in the neurons was more frequently seen in the chronic cases. These findings suggest that the fundamental changes in the neurons in olivary hypertrophy occur within the rough ER. 相似文献
82.
Masahiko Harano Masatoshi Eto Akira Yokomizo Katsunori Tatsugami Masumitsu Hamaguchi Seiji Naito 《Fukuoka igaku zasshi》2007,98(11):389-396
A laparoscopic radical nephrectomy (LRN) for renal cancer can be performed using two methods, hand-assisted laparoscopic surgery (HALS) and standard laparoscopic surgery (SLS). This institute initially used HALS to perform all radical nephrectomy, but gradually shifted to SLS. This study compared the two methods of radical nephrectomy: HALS vs. SLS, which were performed at a single institute. From March 1999 to November 2006, a total 129 patients with pathologically confirmed renal cell carcinoma underwent LRN, including 73 patients with the HALS and 56 patients with SLS. The median operative time was 264 minutes, and median estimated blood loss was 200 ml in the HALS group, respectively. The median operative time and median estimated blood loss in the SLS were 215 minutes and 100 ml, respectively. There was no significant difference in either the operative time or estimated blood loss between HALS and SLS. The median time to both postoperative oral intake and ambulation in the SLS were 1 day. Neither of these events after SLS was significantly shorter than that after HALS. The 4-year disease-free and overall survival rates in the HALS patients were 97.5% and 98.2%, respectively. Both the 4-year disease-free and overall survival rates in the SLS patients were 100%. Since no significant differences were observed between the two operative methods (SLS and HALS) regarding the operative data, postoperative course and oncological outcome, the surgical method for LRN can be selected according to characteristics of each surgical method. 相似文献
83.
Iwao Kadobayashi Masahiko Mori Kunio Tanaka Akiteru Toyoshima Nobukatsu Kato 《Physiology & behavior》1980,25(2):317-320
Small doses (10 and 20 mg/kg) of L-DOPA inhibited the amplitude of the visual evoked response (VER), while large doses (40 and 80 mg/kg) enhanced it. Though low doses (12.5 and 25 mg/kg) of L-5-HTP caused a slight increase in amplitude of the VER, the simultaneous administration of 12.5 mg/kg of L-5-HTP and 10 mg/kg of L-DOPA produced a marked enhancement. The peak latency was prolonged after the injection of any doses of L-DOPA, L-5-HTP, or both. 相似文献
84.
Non-essential amino acid L-serine functions as a highly potent, glia-derived neurotrophic factor, because it is a precursor for syntheses of proteins, other amino acids, membrane lipids, and nucleotides, and also because its biosynthetic enzyme 3-phosphoglycerate dehydrogenase (3PGDH) is preferentially expressed in particular glial cells within the brain. Here we pursued 3PGDH expression in peripheral nerves and its change after crush injury. In the pathway of rat sciatic nerves, 3PGDH was selectively expressed in non-neuronal elements: Schwann sheaths and endoneurial fibroblasts in sciatic nerves, satellite cells in dorsal root ganglia, and astrocytes and oligodendrocytes in the spinal ventral horn. In contrast, 3PGDH was immunonegative in axons, somata of spinal motoneurons and ganglion cells, and endoneurial macrophages. One week after crush injury, 3PGDH was upregulated in the distal segment of injured nerves, where 3PGDH was intensified in activated Schwann cells and fibroblasts. 3PGDH was still negative in activated macrophages, which were instead associated or surrounded by activated Schwann cells with intensified 3PGDH. These results suggest that in the peripheral nervous system, these non-neuronal cells synthesize and may supply L-serine to satisfy metabolic demands for maintenance and regeneration of peripheral nerves and for proliferation and activation of macrophages upon nerve injury. 相似文献
85.
Uni S Shinonaga S Nishio Y Fukunaga A Iseki M Okamoto T Ueda N Miki T 《Journal of medical entomology》1999,36(6):906-908
Nine sarcophagid larvae were found on the right eyelid, cornea, and bulbar conjunctiva of a debilitated patient in a hospital in Osaka, Japan. Inflammation of the right eyelid and conjunctival congestion, probably initiated or aggravated by the larvae, were found. The larvae were removed and reared for accurate identification, and, on the basis of the characteristics of the 3rd instar and adult flies, the species was identified as Sarcophaga crassipalpis Macquart. This is a report of ophthalmomyiasis caused by this facultative parasite in a human. Patients with diminished consciousness in hospitals need protection from flies. 相似文献
86.
Yasuaki Yokoyama Masahiko Okada Hiroshi Sumitomo 《Macromolecular chemistry and physics.》1975,176(10):2815-2832
The cationic copolymerization of 1,3-dioxolane ( 1 ) with 5-methyl-2,3-dihydro-2-furanone ( 2 ) which has two functional groups, a carbon-carbon double bond and a lactone ring, was carried out with three triethyloxonium salts (Et3O+Y?, Y?: BF, FeCl and SbCl), with the boron trifluoride ethyl ether complex, and with tin tetrachloride in nitrobenzene, dichloromethane, and toluene at 0°C. On the basis of the NMR analysis of the microstructure of the copolymer, it was revealed that the growing species of 1 attacked exclusively the carbon-carbon double bond of 2 in the cross-propagation from 1 to 2 , regardless of the solvents and initiators used, except when triethyloxonium hexachloroantimonate was used as initiator. With the latter initiator, the ring opening reaction of 2 by the attack of the growing species of 1 occurred competitively with the usual vinyl addition, although the latter mode of reaction was predominant. The ring opening reaction of 2 with this initiator is probably caused by some specific interaction of monomer 2 with the counter anion. 相似文献
87.
88.
89.
Minoru Imoto Masayoshi Kinoshita Masahiko Nishigaki 《Macromolecular chemistry and physics.》1966,94(1):238-247
The radical mutual copolymerization of p-substituted styrenes, such as p-methoxy-, p-chloro-, p-bromo-, p-cyanostyrene, and styrene was carried out with one another at 30°C. in the dark. As initiator, azobisisobutyronitrile was used. The plots of the copolymerization rates against HAMMETT 's σ values showed no linear relationships and the concave curves were obtained therefrom. The relative reactivities of p-substituted styrenes with a definite p-substituted polystyryl radical, which were shown by the reciprocal of monomer reactivity ratio r1, were plotted against σ values and concave curves were also obtained. The relative reactivities of p-substituted polystyryl radicals with p-substituted styrene were calculated from the ratios r2 and the propagation rate constants in homopolymerization. the plots of them against σ values gave straight lines with different ρ values, according to the polarity of substituents. These results suggest that polar structures in transition state affected markedly the copolymerization rates. The effect of substituents on resonance stabilization was also quantitatively estimated. 相似文献
90.
Anti-p53 antibodies are autoantibodies induced by mutation of p53 cancer-suppressor gene, and are considered to be indirect markers for p53 gene mutations and abnormally high p53 gene levels. We evaluated the usefulness of the measurement of anti-p53 antibodies by enzymed-linked immunosorbent assay using serum samples from patients with various disorders and normal subjects. The anti-p53 antibody concentration was high in patients with lung, esophageal, gastric, hepatocellular, colonic, rectal or ovarian cancer and significantly differed between the group with neoplasms and those with non-neoplastic disorders. Particularly high concentrations were observed in patients with malignant tumors. The mean agreement rate between anti-p53 antibodies and conventional tumor markers was only 47.8% despite slight differences among disorders. The positive rate increased to 63.0% by their combination assay. In addition, anti-p53 antibodies were independent markers, not complimentary to conventional markers. The mean agreement rate between anti-p53 antibodies and tissue p53 was 70.0%. Though the anti-p53 antibody-positive rate was lower than the tissue p53-positive rate, anti-p53 antibodies may be useful new tumor markers because specimens from the affected tissue are not necessary. 相似文献