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141.
142.
We have shown, for the first time, that TNF induces expression of MCMV IE RNA in the lungs of latently infected mice in the absence of immunosuppression. These initial data suggest that TNF may play an important role in the reactivation of latent MCMV, in the absence of immunosuppression, and provide a provocative insight into the mechanisms of CMV reactivation. Studies are in progress to determine whether genes associated with later stages of the viral life cycle are induced by TNF and whether infectious virus is produced.  相似文献   
143.
Carcinogen-resistant inbred DRH rat strain was established from closed colony Donryu rats in the presence of 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB). Despite using 3'-Me-DAB during the stage of selection, the DRH rats developed normally and did not show any spontaneous tumor at over 1 year of age. In the present study, we examined the polymorphism in mannose 6-phosphate/insulin-like growth factor 2 receptor (M6p/Igf2r) gene and found that the DRH rat showed CCC (Proline)-type polymorphism in exon 48 and the Donryu rat had GCC (Alanine) sequence. Since the DRH rat was developed from the Donryu rat, we examined whether this polymorphism in exon 48 of M6p/Igf2r gene was due to mutation that occurred at the stage of selection in the presence of 3'-Me-DAB, using several other laboratory and wild rats. We detected the presence of polymorphism at the same site of the M6p/Igf2r gene among these rats. It is likely that the polymorphism in exon 48 of the M6p/Igf2r gene is present broadly in rats since ancient times and not due to the mutation during the course of selection unless this site is a hot spot for chemical carcinogens.  相似文献   
144.
为改善用户界面的可用性提供有益信息,提出了一种基于任务模型的界面评估办法.首先简要介绍了任务模型及并行任务树表示法,然后重点介绍了基于任务模型的界面评估的实现方法,并以实例说明该方法能有助于改善用户界面.  相似文献   
145.
目的测量了新型光敏剂NPe6(Mone-L-Aspartyl Chlorin e6,NPe6)在白鼠(BALB/C,雄性)脑组织中的吸收情况,为减少光动力学疗法对正常脑组织的损伤提供关键的实验数据.方法首次采用了激光诱导荧光产额测量的方法,测得NPe6在脑组织中的吸收情况,并观测激光照射下给予NPe6和未给予组鼠的不同反应.结果实验测量光敏剂NPe6在鼠脑组织的浓度随时间变化的情况,与已报道的同位素标记方法所得结果一致.观测了激光照射下给药和未给药组鼠的不同反应,发现在相同给药量和激光辐照能量下,随着给药和激光辐照时间间隔的延长,死亡的鼠数目减少;未给药组鼠对激光照射没有可察觉的反应.结论 NPe6能被正常脑组织迅速摄取和排除,可望能用于临床.  相似文献   
146.
对自能源减速器称重过程的动态性能进行机理研究,建立了称重动态过程的数学模型,并进行了仿真计算,仿真结果与实测吻合.在此基础上分析了溜放速度、容腔及管路内油液的可压缩性对称重结果的影响.首次提出了"完全称重"、"部分称重"、"重复称重"的概念,为减速顶的设计提供新的理论依据.  相似文献   
147.
目的:探讨白内障超乳化摘除,睫状体平坦部下班体切割及人工晶体囊袋内植入联合手术的疗效及安全性。方法:对玻璃体视网膜病普合并白内障18例(18眼)施行该联合手术。其中糖尿病性视网膜病变,玻璃体出血伴白内障10例;视网膜分枝静脉阻塞,玻璃体出血伴白内障4例;视网膜静脉周围炎,玻璃体出血伴白内障3例及特发性视网膜1例,术后随访2~13个月(平均9月)。结果:术后视力均有不同程度提高。12眼(67%)术后  相似文献   
148.
PURPOSE: Subconjunctival fibroblasts play a critical role in scarring and treatment failure in fistulizing surgery for glaucoma. The proliferation of subconjunctival fibroblasts appears to be modulated by topical glaucoma medications. This study was conducted to evaluate the effects of latanoprost and brimonidine on subconjunctival fibroblast proliferation in rabbit eyes. METHODS: Twelve pigmented Dutch-belted rabbits were divided into treatment groups of four: latanoprost 0.005%, brimonidine 0.2%, or balanced saline solution (BSS) each were administered to one treatment group, both eyes of each rabbit, twice a day, 6 days a week for 10 weeks. The eyes were then enucleated along with the conjunctiva, fixed, processed, and evaluated by light microscopy and immunohistochemistry using anti-proliferating cell nuclear antigen (PCNA) and anti-muscle-specific actin antibody (HHF-35). Fibroblast cell counts were performed at magnification x40. RESULTS: In all groups, few inflammatory cells were seen in the subconjunctival space under light microscopy. PCNA staining revealed a statistically significant increase in the mean number of labeled fibroblasts in the group receiving brimonidine compared with the control (BSS) group. The group receiving latanoprost also had a significantly higher mean number of labeled fibroblasts than the groups receiving brimonidine or BSS. Only a few fibroblasts stained positively with the anti HHF antibody. Eyes treated with latanoprost, however, had significantly higher numbers of positively labeled cells than eyes treated with brimonidine or BSS. CONCLUSION: When applied to rabbit eyes, latanoprost and brimonidine appear to increase the number of positively labeled proliferating subconjunctival fibroblasts.  相似文献   
149.
We previously reported the discovery of 14 channels in the human body, which possessed the biophysical property of high emission of light. In this study we found the same property on the Ren and Du channels in healthy rats. Additionally, we discovered that the luminance of the related channels in rat models with different "syndromes" varied greatly. For instance, a markedly low luminance appeared on the Du channel in animals with experimental syndrome of Yang deficiency induced by hydrocortisone; while in animals with experimental syndrome of blood deficiency caused by bleeding, an apparently low luminance occurred on the Ren channel. The intensity of the emitted light on Du and Ren channels increased after acupuncture treatment, but not significantly. This phenomenon conforms to the theory in traditional Chinese medicine that the Du channel is the "sea of Yang channels", while the Ren channel is the "sea of Yin channels".  相似文献   
150.
Anti-GQ1b antibodies are typically found in patients with the Miller Fisher syndrome, all of whom will have, by definition, acute ophthalmoplegia. The authors describe three patients with chronic ophthalmoplegia in the presence of persistently high titers of immunoglobulin G anti-GQ1b antibody detected in an ELISA, one of whom improved with immunotherapy. Anti-GQ1b antibodies may be associated with some cases of chronic ophthalmoplegia of unknown cause.  相似文献   
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