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991.
作者改进了巢-聚合酶链反应技术.在第一轮聚合酶链反应(PCR)之后,进行低融点琼脂糖凝电泳.切下靶序列带或相应位置的凝胶,加热融化后稀释,再进行第二轮PCR.由于对第一轮反应的产物进行了电泳纯化,所以可进一步提高这种方法的特异性.用这种方法研究了转基因小鼠中抗体基因的表达. 相似文献
992.
Effects of epidermal growth factor, fibroblast growth factor, and transforming growth factor-beta on corneal cell chemotaxis. 总被引:5,自引:0,他引:5
M B Grant P T Khaw G S Schultz J L Adams R W Shimizu 《Investigative ophthalmology & visual science》1992,33(12):3292-3301
The effects of recombinant basic fibroblast growth factor (FGF), epidermal growth factor (EGF), and transforming growth factor-beta (TGF-beta) on migration of human and bovine corneal cells were determined using checkerboard analysis in Boyden chambers. EGF, FGF, and TGF-beta each stimulated high levels of chemotactic migration. Each growth factor, however, induced a different dose-response pattern. Migration stimulated by FGF reached a plateau at a concentration between 100 and 200 ng/ml for endothelial, epithelial, and stromal fibroblasts. By contrast, chemotactic responses to EGF peaked between 10 and 50 ng/ml, then decreased at higher concentrations. TGF-beta also stimulated a peak in migration in all three corneal cells, but the peak of migration occurred at an approximately 1000-fold lower concentration (1 pg/ml) than for EGF. Checkerboard analysis demonstrated that FGF and EGF, but not TGF-beta, stimulated chemokinesis of bovine, stromal, and endothelial cells. These results demonstrate that FGF, EGF, and TGF-beta induce migration in pure populations of bovine and human corneal cells and support the concept that these growth factors may play key roles in corneal wound healing by regulating migration of corneal cells. 相似文献
993.
ACNU [1-(4-amino-2-methyl-5-pyrimidinyl) methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride], one of the chloroethylnitrosoureas (CENUs), is believed to be effective against malignant glioma when intravenously or intrathecally administered. A rat model with meningeal gliomatosis (MG) induced by an intracisternal inoculation of rat C6 or 9L glioma cells was intrathecally and intravenously treated with ACNU in order to test the feasibility of intrathecal chemotherapy with ACNU in the treatment of meningeal gliomatosis. The median survival time (MST) of the animals was significantly prolonged when ACNU was intrathecally administered at dosages of 0.5 to 1.5 mg kg-1 in the early stages of MG, i.e. within 3 days after the tumour inoculation, whereas intravenous therapy with ACNU at a dose of 15 mg kg-1 did not exhibit any efficacy in the rats inoculated with C6 glioma cells (C6-MG). Intrathecal ACNU, however, at dosages of up to 1.5 mg kg-1 failed to demonstrate any therapeutic effect in the late stage of MG, i.e. 5 days after the tumour inoculation, except in the rats inoculated with 9L brain tumour cells (9L-MG). Intravenous chemotherapy with ACNU at a dose of 15 mg kg-1 extended the MST of the 9L-MG rats more significantly in the late stage of MG than in its early stage. This points to the feasibility of intrathecal ACNU in the treatment of meningeal gliomatosis in its early stages, but not in its late stages in which intravenous ACNU might be more effective than intrathecal treatment against MG of which the parenchyma has already been deeply invaded by the tumour. 相似文献
994.
Hideo Nakamura Yuichi Yokoyama Yasuhiro Seto Toshiaki Kadokawa Masanao Shimizu 《The Journal of pharmacy and pharmacology》1984,36(3):182-186
The antipyretic activity of AD-1590 (2-[8-methyl-10,11-oxodibenz[b,f]oxepin-2-yl]propionic acid), a non-steroidal anti-inflammatory drug with a novel chemical structure, was investigated in rabbits with lipopolysaccharide (LPS)-induced fever and monkeys with leucocytic pyrogen-induced fever. AD-1590 produced a dose-related inhibition of the LPS-fever at oral doses of 0·1 mg kg−1 or more (ED50 = 0·089 mg kg−1). Its potency was 10–12, 20–35, 100–170, 400–540, >1500 and >2000 times that of ketoprofen, diclofenac sodium, indomethacin, ibuprofen, mefenamic acid and aspirin, respectively. The fever caused by leucocytic pyrogen was significantly inhibited by intravenous administration of 0·1–0·2 mg kg−1 of AD-1590. AD-1590 (10 mg kg−1 oral or i.v.) did not affect body temperature in afebrile rabbits or monkeys. These results suggest that AD-1590 shows a potent antipyretic activity in the rabbit and monkey and is a potent antagonist of LPS-fever. 相似文献
995.
996.
997.
G Miyamoto H Sasabe N Tominaga N Uegaki M Tominaga T Shimizu 《Xenobiotica; the fate of foreign compounds in biological systems》1988,18(10):1143-1155
1. After OPC-8212 was orally given to rats, mice, dogs, monkeys and humans, its metabolites were identified by n.m.r. and mass spectrometry, and their concentrations in the plasma, urine and faeces of these species were measured by high-performance liquid chromatography (h.p.l.c.). 2. Hydrolysis of the amide group, oxidation and cleavage of the piperazine ring, O-demethylation of the methoxy group, and conjugation were proposed as metabolic pathways of OPC-8212. 3. In rats, mice and monkeys given OPC-8212 orally, metabolites M-1 to M-6 were detected in the plasma, urine and faeces, while M-1, -4, -5 and M-6 were detected in dogs, and M-1, M-3, M-4, M-5 and M-6 were detected in humans. 4. Conjugates of metabolites M-6 and M-7, with glucuronic acid and sulphuric acid, were observed in the urine of rats and humans. 相似文献
998.
999.
We report a sporadic case of periodic ataxia characterized by recurrent attacks of vertigo and ataxia. A 62-year-old male was known to have nystagmus at the age of 18. He has had recurrent episodes of vertigo and ataxia since the age of 48. During an attack remarkable downbeat nystagmus, limb ataxia predominant in the lower extremities and ataxic gait were present. MRI demonstrated an atrophy of the anterosuperior region of the cerebellar vermis. Vertical nystagmus, dysesthesia of gloves and stocking type and deep sensory disorder persisted during interictal intervals. There is no finding which supports this case to be vascular disorder, congenital anomaly, tumor, infection or demyelinating disease. We thought this case to be periodic ataxia and to belong to vestibulocerebellar ataxia reported by Farmer and his colleagues. 相似文献
1000.
Behavioral changes after focal cerebral ischemia by left middle cerebral artery occlusion in rats 总被引:8,自引:0,他引:8
Behavioral changes after occlusion of the left middle cerebral artery (MCA) in rats were investigated for 16 weeks. Impairment of motor coordination and incidence of neurological deficits including hemiplegia and abnormal posture were present for the first 2 and 4 weeks after MCA occlusion, respectively. Learning behavior in one-trial passive avoidance task was disturbed for the entire 16-week period when rats were trained at days 3 after MCA occlusion. Reacquisition was also impaired when rats were retrained on 8 weeks after MCA occlusion. Except for synchronized EEG at days 2 after MCA occlusion, significant changes in spontaneous movement and EEG were not observed in the MCA-occluded group. These results suggest that this rat model of MCA-occlusion is useful for quantitatively measuring functional changes in chronic phase of focal cerebral ischemia. 相似文献