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71.
腺病毒介导的HSV—tk基因治疗大鼠脑胶质瘤实验研究 总被引:4,自引:0,他引:4
目的:带有HSV-tk基因的重组腺病毒(AdHCMV-tk)结合核苷类似物(NA)治疗大鼠C6脑胶质瘤。方法:用X-gal染色测定AdHCMV-lacZ转染大鼠C6胶质瘤细胞的效率。用AdHCMV-tk/ACV、GCV离体及活体治疗大鼠C6胶质瘤。结果:AdHCMV-lacZ感染C6细胞效率达100%,AdHCMV-tk感染C6细胞,在病毒感染复数为1000时,GCV和ACV半致死剂量分别为3μg/ml和20μg/ml,Ad-HCMV-tk/ACV治疗大鼠C6胶质瘤模型,大鼠生存期超过90天,而对照组分别为17.0±1.6天(生理盐水组)、14.5±1.3天(AdHCMV-lacZ组),P<0.001。结论:重组腺病毒对靶细胞感染效率可达100%,AdHCMV-tk用GCV的杀伤C6胶质瘤细胞比ACV强,而HSV-tk/ACV用腺病毒介导治疗大鼠脑肿瘤疗效显著。 相似文献
72.
本研究选择10μg/ml、20μg/ml、40μg/ml浓度的溴氰菊酯处理白纹伊蚊C6/36细胞,以MMC作为阳性对照物,观察溴氰菊酯处理24h后对C6/36细胞染色体畸变率和姐妹染色单体互换(SCE)频率的影响。结果显示,三个浓度的溴氰菊酯对C6/36细胞染色体畸变率均没有显著影响(P<0.05);溴氰菊酯浓度在40μg/ml时可诱导C6/36细胞SCE频率轻度增高(P>0.05),而溴氰菊酯浓度在10μg/ml、20μg/ml时,对C6/36细胞SCE频率没有诱导作用。表明溴氰菊酯对C6/36细胞的遗传学效应较弱 相似文献
73.
目的:了解改水降氟后地氟病的防治效果。方法:水氟,尿氟测定均为电极法,氟斑牙诊断为Dean‘s法。结果:该村自1985年改饮低氟水,水氟含量由改水前的6.05mg/L降至改水后的0.48mg/L。改水后未出现新的氟骨症患者,8-12岁儿童氟斑牙患病率呈逐年下降趋势,改水后7-15年间氟斑牙病率均已稳定,表明病情得到有效控制,且达到稳定控制状态,结论:坚持长年饮用低氟水,地方性氟中毒就能得到有效控制。 相似文献
74.
The present study examined the influences of dopamine (DA) receptor stimulation on enkephalin (Met5-enkephalin; ME) and tachykinin (substance P; SP) systems of basal ganglia of Sprague-Dawley rats, lesioned as neonates with 6-hydroxydopamine (6-OHDA). It has been proposed that the neonatal 6-OHDA-lesioned rat could serve as a model for the DA deficiency and self-injurious behavior (SIB) observed in the childhood neurological disorder. Lesch-Nyhan syndrome. In agreement with earlier work, the present study found that the neonatal 6-OHDA treatment at 3 days of age, reduced DA and caused an increase in ME and a decrease in SP content in the striatum and substantia nigra, when tested as adults. Administration of the DA precursor, L-dihydroxyphenylalanine (L-DOPA), to lesioned animals, induced SIB; increased DA and DOPAC levels; produced a greater decrease (-64%) in SP levels in the striatum and substantia nigra than was observed with lesion alone (-28%). The L-DOPA-induced decrease in SP levels and the SIB observed in the lesioned animals were blocked by pretreatment with the D1 receptor antagonist, SCH-23390. Moreover, administration of the D1 receptor agonist, SKF-38393, but not the D2 agonist, LY-171555, to lesioned animals mimicked the L-DOPA responses in all respects, except that the agonists did not alter DA or DOPAC levels. None of the DA agonists or antagonists treatments affected lesion-induced increase in ME levels in the striatum. These results indicate for the first time, that SIB precipitated by DA agonists in neonatal dopaminergic denervated animals, is associated with a marked and selective decrease in SP in the striatonigral SP neurons. This process has two components: (a) a retarded development of the SP system due to neonatal dopaminergic denervation: and (b) a depletion of the remaining SP, presumably by enhanced release due to D1 DA receptor-mediated activation of striatonigral SP neurons. 相似文献
75.
76.
"立交桥"高职护理人才培养模式初探 总被引:3,自引:1,他引:2
为探讨中等卫生学校毕业就读高等护理专业学生(即“立交桥”高职)的培养模式,在坚持高等教育培养目标及职业特色的前提下,结合学生特点,进行课程设置、教学方法及临床实践等方面的改革,以发挥学生的优势,弥补学生的不足,培养适应现代护理发展需要的高质量护理人才。 相似文献
77.
78.
Effects of antimicrobial agents on spontaneous and endotoxin-induced cytokine release of human peripheral blood mononuclear cells 总被引:2,自引:0,他引:2
U. Krehmeier M. Bardenheuer G. Voggenreiter U. Obertacke F. U. Schade M. Majetschak 《Journal of infection and chemotherapy》2002,8(2):194-197
Because the immunomodulatory effects of antibiotics could possibly influence the degree of the systemic and local response
to infection, knowledge of their intrinsic influence on the host's inflammatory response appears to be essential. Therefore,
this study investigated the effects of frequently used antimicrobial agents (β-lactams, quinolones gentamicin, vancomycin
and metronidazole) on the in-vitro tumor necrosis factor (TNF)-α and interleukin (IL)-6 production of isolated human peripheral
blood mononuclear cells (PBMNC), cultured with or without endotoxin, in comparison with those effects obtained in a whole-blood
assay system. In the presence of ciprofloxacin, ofloxacin, gentamicin, vancomycin, and metronidazole, a significant inhibition
of the endotoxin-stimulated TNF-α production of human peripheral blood mononuclear cells (PBMNC) was found at therapeutic
levels. Only ofloxacin showed a significant inhibitory influence on the endotoxin-induced IL-6 production of PBMNC. In the
whole-blood assay, significant effects were not detectable. None of the antibiotics showed cytotoxicity. It is concluded that,
at present, the direct immunological effects of antibiotics should be interpreted carefully with regard to the experimental
conditions, and regardless of the therapeutic implications. To assess the potential direct immunomodulatory effect of antimicrobial
agents, different cell culture procedures should be used.
Received: October 19, 2001 / Accepted: February 15, 2002 相似文献
79.
Transplantation of microencapsulated bovine chromaffin cells reduces lesion-induced rotational asymmetry in rats 总被引:7,自引:0,他引:7
Surrounding bovine chromaffin cells by a semipermeable membrane may protect the transplanted cells from a host immune response and shield them from the inflammatory process resulting from the surgical trauma. Encapsulation of the chromaffin cells was achieved by inter-facial adsorption of a polycation on a polyanionic colloid matrix in which the chromaffin cells were entrapped. Basal and potassium-evoked release of catecholamines from encapsulated bovine chromaffin cells was analyzed over a 4-week period in vitro. Norepinephrine and dopamine release remained constant over time whereas epinephrine release significantly decreased. The chromaffin cells also retained the capacity for depolarization-elicited catecholamine release 4 weeks following the encapsulation procedure. Morphological analysis revealed the presence of intact chromaffin cells with well-preserved secretory granules. Striatial implantation of chromaffin cell-loaded capsules significantly reduced apomorphine-induced rotation compared to empty polymer capsules in animals lesioned with 6-hydroxydopamne frr at least 4 weeks. Intact chromaffin cells expressing tyrosine hydroxylase and dopamine-β-hydroxylase were observed in all capsules implanted in the striatum for 4 weeks. The assessment of the clinical potential of transplanting encapsulated adrenal chromaffin cells of either allo- or xenogeneic origin for Parkinson's disease will require long-term behavioral studies. The present study suggests, however, that the polymer encapsulation procedure may offer an alternative to adrenal autografts as a source of dopaminergic tissue. 相似文献
80.
We performed an open, double-blind, and long-term study of vigabatrin (gamma-vinyl-GABA, GVG) in patients with treatment-resistant epilepsy who were receiving only one or at most two standard antiepileptic drugs (AEDs). The novel design included a parallel, double-blind, placebo-controlled phase that minimized the number of patients receiving placebo and allowed determination of the optimum dose of GVG for each patient before initiation of the double-blind phase. The study was divided into four phases. The first phase was a 6-week period of baseline observation. In the second phase, GVG was added openly to previous AEDs for 8 weeks. During the first 2 weeks of this phase, the dose of GVG was increased weekly and then, in the absence of adverse effects, was held constant for the next 6 weeks. At the end of this open phase, seizure frequency during the 6 weeks of constant treatment was compared with the baseline seizure frequency for each patient. Patients who experienced reduction greater than 50% in the frequency of any seizure type during the open phase were defined as responders. These responders were then entered into the third and double-blind phase, in which they were randomly allocated wither to continue active GVG treatment or placebo for 8 weeks. Thirty-three patients entered the study; 31 of 33 patients completed the initial open phase. Twenty patients achieved a reduction greater than or equal to 50% in the frequency of one or more seizure types and were eligible for the double-blind phase; 10 were randomized to continue GVG and 10 were randomized to placebo.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献