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61.
目的在体内实验中观察钙依赖性膜磷脂结合蛋白AnnexinⅡ对大鼠脊髓损伤以及神经干细胞移植的作用。方法在成年大鼠全横断脊髓损伤的局部微量注射AnnexinⅡ,观察其对损伤的脊髓神经细胞存活、神经纤维生长和损伤后的功能恢复的影响,以及对联合移植的胚胎神经干细胞移植后存活和迁移的影响。结果在动物脊髓横断损伤6周,神经干细胞移植4周后,损伤局部微量注射AnnexinⅡ+NSC移植组实验动物的运动评分结果较空白对照组和单独进行NSC移植组都有明显增高(JP〈0.01),脊髓损伤处的空洞面积也较上述两组显著减小(P〈0.01);注射AnnexinⅡ+NSC组损伤节段以上荧光金标记神经细胞数目较空白对照组明显增多(P〈0.01)。结论AnnexinⅡ蛋白可能具有减小局部损伤空洞面积,保护损伤的神经元和神经纤维并防止其走向变性和死亡的效应,并对神经干细胞的移植效应有一定的促进和协同作用,使脊髓损伤大鼠的功能得到一定程度的恢复。 相似文献
62.
Jacques C. Giltay Klasien B. J. Gerssen-Schoorl Ab van der Wagen 《Clinical genetics》1994,46(3):271-272
The present paper describes a girl with a small de novo deletion of chromosome 9(p12p13). This deletion has not been published previously. The deleted fragment is clearly outside the region involved in the so-called deletion 9p syndrome. The patient had mild dysmorphic features and feeding problems during the first weeks of life, but is now developing well. Because of the lack of severe clinical features in this patient, we speculate that the deletion may be prevalent in other patients who have no clinical indication for chromosome investigation. 相似文献
63.
64.
入伍新兵适应性问题的质化研究 总被引:1,自引:0,他引:1
目的了解入伍新兵的适应性问题现状。方法采取最大差异抽样,运用访谈法收集资料,基于扎根理论对资料进行分析。结果新兵由于年龄、兵源、文化层次等的不同,在入伍动机、生活和心理方面适应存在显著的差异。结论部队管理可以从以上方面进行干预,以提高新兵对部队的适应性。 相似文献
65.
目的对研究获得的强迫症疾病行为特征探索其精神病理学机制。方法以符合CCMD-Ⅱ的门诊强迫症患者50例为对象,选取非精神科病人50例组成对照,应用“强迫症疾病行为特征量表(OBPS)”,确定其有无强迫症疾病行为。同时调查研究组与对照组的人格特质、偶发事件、应对策略等方面,研究这些因素在疾病发生、发展中的作用。结果①研究组全部符合李一高量表的疾病行为特征,积分明显高于对照组(t=26.480,P〈0.01);②强迫症患者人格当中的强迫质偏高,积分明显高于对照组(t=15.93,P〈0.01);③研究组中绝大多数患者存在偶发事件,而对照组中偶发事件的发生率低于研究组(X^2=21.374,P〈0.01);④应对策略特征方面研究组不成熟应对方式的应用明显多于对照组。结论强迫神经症形成中人格特质作为基础,偶发事件起到启动对“不完全的恐怖”,错误的应对策略不断强化病感,促进疾病形成。李一高强迫症疾病行为理论的3项内容,特征性的反映了强迫症的疾病行为。 相似文献
66.
The fact that electrical stimulation of the lateral hypothalamus (LH) can be substituted for the delivery of a food pellet in typical schedule induced polydipsia was established and demonstrated the role of this part of the brain in the mediation of adjunctive behavior. The assumption that Δ9-tetrahydrocannabinol (Δ9-THC) and ethyl alcohol affect behavior because of a differential effect on the same LH mechanism was supported by the following evidence. Relatively small doses of Δ9-THC, 0.25, 0.375, and 0.50 mg/kg, enhanced adjunctive drinking; whereas, larger quantities of 0.625 and 0.75 mg/kg had no appreciable effects. The effect is somewhat specific, as it did not occur with strychnine sulfate, and rate dependent within limits as it was most pronounced in animals with low rates of responding or in animals when responding at a low rate. The effect of rate dependency was also apparent with fixed interval schedules of 2 and 4 min and a multiple schedule of a fixed interval and a signalled timed out period of nonreinforcement. Low rates of responding were enhanced by all doses of Δ9-THC, 1.0, 1.5, 2.0, 2,5, and 3.0 mg/kg, and there was an obvious dose related decrease in high rates. A similar effect was observed with low and high rates of electrical self-stimulation through implanted LH electrodes. The hypothesis that some drugs such as Δ9-THC and ethyl alcohol can enhance the positive feedback in an LH mediated motor control system by the facilitation of the same mechanism which initially generated the behavior was confirmed. Oral self administration of ethyl alcohol in a saccharin sweetened fluid enhanced recovered adjunctive drinking of the solution in quantities which should be sufficient to produce physical dependence if continued for relatively long periods. Recovered adjunctive drinking occurs in animals without food or water deprivation and it is an intense and persistent phenomenon. 相似文献
67.
Charles A. Horwitz J. Carlos Manivel Subbarao Inampudi Keith Kaye Chris S. Jensen Michael B. Cohen 《Diagnostic cytopathology》1994,11(4):380-384
In recent years, fine-needle-aspiration biopsies (FNA) have been widely used in the evaluation of renal masses, with false-positive FNA data being very uncommon. We present a case report of a 76-yr-old man with a 16-cm renal cyst and what was interpreted as an isolated calcified mural nodule. Following drainage of the main cyst fluid, FNA biopsy showed atypical cell clusters thought to be positive for malignancy. Subsequent surgery failed to disclose either a residual mural nodule or evidence of malignancy. Immunoperoxidase studies performed on both the cell block and actual cyst wall suggested that the abnormal cells were histiocytes. The diagnostic pitfalls of this case, along with a review of pertinent literature, are discussed. Diagn Cytopathol 1994; 11:380–384. © 1994 Wiley-Liss, Inc. 相似文献
68.
Behavioral and neurochemical effects induced by subchronic combined exposure to toluene at 40 ppm and noise at 80 dB-A in rats 总被引:1,自引:0,他引:1
We investigated whether exposure to noise, in addition to its well-known potentiating effect on toluene-induced ototoxicity, may also exacerbate behavioral disturbances and brain neurochemical alterations produced by subchronic exposure to low toluene concentration. To test this hypothesis, we evaluated whether subchronic combined exposure (16 weeks, 104 h per week) to noise at 80 dB-A and toluene at 40 ppm potentiates the recently reported neurotoxic effects of subchronic exposure to 40 ppm toluene. Locomotor and rearing activities, sensitization to narcosis induced by acute toluene at high concentration, and tyrosine and tryptophan hydroxylase activities in the caudate-putamen and hippocampus were investigated in both male and female rats. Our results confirm that subchronic exposure to 40 ppm toluene significantly decreases rearing activity and leads to a sensitization to toluene-induced narcosis, as evaluated by loss of righting reflex, but fails to demonstrate any adverse effect of noise, alone or in combination with toluene. Given that toluene has addictive properties, the lack of potentiating behavioral and neurochemical effect of noise is discussed with regards to a recent study that has shown that methamphetamine neurotoxicity is potentiated by exposure to loud noise. 相似文献
69.
Diagnosis of paracoccidioidomycosis in an immigrant who had returned to Italy following a long sojourn in Venezuela prompted a review of imported cases of this Latin American disease in nonendemic countries. Forty-two such instances of well documented paracoccidioidomycosis were compiled. Among these, eleven individuals had arrived in nonendemic countries with active symptomatic infections, fifteen others were first suspected of having tuberculosis, and four each were considered to have blastomycosis caused by Blastomyces dermatidis and carcinomas. Three, individuals were considered to have Wegner's granulomatosis or blastomycosis. Two other patients were treated for syphilis before being diagnosed as having paracocidioidomycosis. A striking feature of most of these cases was the long asymptomatic period following initial infection. The dormant periods ranged form four months to 60 years with an average duration of 14 years. The need to question patients about travel to or residency in foreign countries is emphasized, along with the necessity to include the mycoses in differential diagnoses. Three reported cases, all from Africa with no history of travel to the endemic areas of the New World, were considered to be doubtful. In one of these, Russell bodies apparently had been mistaken for the tissue-form cells of Paracoccidioides brasiliensis. A Japanese case, upon restudy of available histologic slides, revealed that the fungal cells present in various organs were those of Cryptococcus neoformans and not of P. brasiliensis.Corresponding author 相似文献
70.
Boguslaw Barański 《Archives of toxicology》1986,58(4):255-260
Administration of 60 ppm cadmium (Cd) in drinking water from the 1st to the 20th day of gestation to female rats did not affect the viability, body weight gain, food, and water consumption of offspring. The blood hemoglobin level was reduced in 2-week-old females and males but not in 16-week-old offspring. Hematocrit and serum glucose level were not affected at either age. Cadmium concentration in the intestinal wall was increased in both age groups, with marginal uptake in other organs. A decrease in copper (Cu) concentration was found in the brain of 2-week-old offspring of both sexes and of 16-week-old females. The brain zinc (Zn) concentration was decreased only in 16-week-old animals. The physical and neuromuscular development of offspring before weaning was not impaired by maternal Cd treatment. The alterations in Cu and Zn metabolism were associated with reduced locomotor activity and affected open-field behavior in adult offspring of either sex and with decreased avoidance acquisition in adult female offspring.The results obtained suggest a relationship between the reduced brain Cu and Zn levels and CNS dysfunction in adult offspring of female rats exposed to Cd during gestation. 相似文献