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991.
目的:探讨血浆uPA、uPAR在不同分子亚型乳腺癌中的表达水平及其对乳腺癌患者治疗、预后等的临床意义。方法:采用免疫组化ELISA方法测定的女性乳腺癌初治患者86例的血浆uPA、uPAR水平,所有患者均经组织病理学确诊,以患者的临床病理学资料提供的免疫组化结果为基础进行分子分型,结合二者进行分析。结果:血浆uPA在乳腺癌不同分子亚型中表达有统计学差异(P〈0.01),uPAR在乳腺癌不同分子亚型中表达有统计学差异(P〈0.05);乳腺癌患者血浆uPA和uPAR呈显著正相关(P〈0.01,Pearson相关系数(r=0.735)。结论:乳腺癌患者血浆uPA和uPAR的水平与分子亚型密切相关,他们和分子亚型联合,可能对乳腺癌个体化治疗及判定预后有指导意义。 相似文献
992.
993.
目的:应用改良CCI模型研究外周神经损伤后痛觉过敏和自发放电各自特征及相互关系.方法:雄性SD大鼠,随机分为CCI组和Sham组,分别于术前1天和术后1、4、7、9、11、14天测定机械刺激缩足反射阈值和热缩腿反射潜伏期,同时选取术侧机械刺激缩腿反射阈值低于4g或者术侧和健侧热缩腿反射潜伏期差异大于2s的CCI模型大鼠观察术后4-14天损伤区自发放电活动.结果:神经纤维损伤后,机械痛敏和热痛敏随时间表现为逐渐增强,同时在损伤区观察到三类放电模式:整数倍放电阵发放电和周期放电.结论:术后大鼠机械痛阈和热痛阈逐渐降低,机械痛敏的产生和损伤区自发放电活动关系密切,不同的放电模式可能代表不同的传入信息. 相似文献
994.
995.
Pandemic H1N1/2009 influenza virus, derived from a reassortment of avian, human, and swine influenza viruses, possesses a unique gene segment combination that had not been detected previously in animal and human populations. Whether such a gene combination could result in the pathogenicity and transmission as H1N1/2009 virus remains unclear. In the present study, we used reverse genetics to construct a reassortant virus (rH1N1) with the same gene combination as H1N1/2009 virus (NA and M genes from a Eurasian avian-like H1N1 swine virus and another six genes from a North American triple-reassortant H1N2 swine virus). Characterization of rH1N1 in mice showed that this virus had higher replicability and pathogenicity than those of the seasonal human H1N1 and Eurasian avian-like swine H1N1 viruses, but was similar to the H1N1/2009 and triple-reassortant H1N2 viruses. Experiments performed on guinea pigs showed that rH1N1 was not transmissible, whereas pandemic H1N1/2009 displayed efficient transmissibility. To further determine which gene segment played a key role in transmissibility, we constructed a series of reassortants derived from rH1N1 and H1N1/2009 viruses. Direct contact transmission studies demonstrated that the HA and NS genes contributed to the transmission of H1N1/2009 virus. Second, the HA gene of H1N1/2009 virus, when combined with the H1N1/2009 NA gene, conferred efficient contact transmission among guinea pigs. The present results reveal that not only gene segment reassortment but also amino acid mutation were needed for the generation of the pandemic influenza virus. 相似文献
996.
Background
The impact of variation of Epstein-Barr virus (EBV) antibody titers before the development of nasopharyngeal carcinoma (NPC) is still unclear. We analyzed the fluctuations of antibodies against EBV before histopathological diagnosis to assess the risk of NPC and aimed to provide a reliable basis for screening in high risk populations.Methods
This study was based on a population-based screening program in Sihui County in Guangdong Province of China. A total of 18,986 subjects were recruited in 1987 and 1992, respectively. Baseline and repeated serological tests were performed for IgA antibodies against EBV capsid antigen (VCA/IgA) and early antigen (EA/IgA). Follow-up until the end of 2007 was accomplished through linkage with population and health registers. Cox proportional hazards regression model was used to estimate the relative risk of NPC in association with EBV antibodies. Time-dependent receiver operating characteristic curve (ROC) analysis was used to further evaluate the predictive ability.Results
A total of 125 NPCs occurred during an average of 16.9 years of follow-up. Using baseline information alone or together with repeated measurements, serological levels of VCA/IgA and EA/IgA were significantly associated with increased risks for NPC, with a striking dose-response relationship and most prominent during the first 5 years of follow-up. Considering the fluctuant types of serological titers observed during the first three tests, relative risk was highest among participants with ascending titers of EBV VCA/IgA antibodies with an adjusted hazard ratio (HR) of 21.3 (95% confidence interval [CI] 7.1 to 64.1), and lowest for those with decreasing titers (HR = 1.5, 95% CI 0.2 to 11.4), during the first 5 years of follow-up. Time-dependent ROC analysis showed that VCA/IgA had better predictive performance for NPC incidence than EA/IgA.Conclusion
Our study documents that elevated EBV antibodies, particularly with ascending titers, are strongly associated with an increased risk for NPC. 相似文献997.
Rujuan Liu Hang Xu Yanli Wang Weimin Gong 《Biochemical and biophysical research communications》2009,379(1):92-97
It is well known that motion of LID and NMP-binding (NMPbind) domains in adenylate kinase (AK) is important in ligand binding and catalysis. However, the nature of such domain motions is poorly characterized. One of the critical hinge regions is hinge IV, which connects the CORE and LID domains. In addition, the hinge IV contains a strictly conserved residue, L171, in the AK family. To investigate the role of hinge IV, crystal structure of human adenylate kinase 4 (AK4) L171P mutant was determined. This mutation dramatically changes the orientation of the LID domain, which could be described as a novel twisted-and-closed conformation in contrast to the open and closed conformations in other AKs. This mutant provides a new example of domain motions in AK family. 相似文献
998.
In October 1999, the authors received fixed specimens of a species of Longidorus from Howard Ferris found about the roots of a citrus tree in Oakville, Napa County, CA. After determining it to be new a species, we requested additional specimens. The samples contained roughly equal numbers of males and females. Longidorus ferrisi n. sp. is most similar to L. elongatus, but can be distinguished by a greater c-ratio (111-187 vs 73-141), a lesser c′ (0.7-1.1 vs 1.0-1.3), a more offset head, a more posterior guide ring (35-40 vs 30-33 μm), the presence of sperm in the uterus in mature females, and the approximate 1:1 ratio of females to males. Other similar species include L. artemisiae, L. crassus, L. glycines, and L. milanis. Longidorus ferrisi n. sp. differs from L. artemisiae by a lesser a-ratio (74-102 vs 109-155), a lesser c′ value (0.7-1.1 vs 1.0-1.6), a more posterior guide ring (35-40 vs 27-34 μm), a longer odontostyle (91-108 vs 84-98 μm), a wider lip region (16-19 vs 14-17 μm), wider mid-body (53-69 vs 41-52 μm), and longer spicules (57-65 vs 39-49 μm). The new species differs substantially from L. crassus by its lip shape and the presence of males, and differs from L. glycines by a shorter body (4.33-5.97 vs 6.14-8.31 mm), a lesser c′ value (0.7-1.1 vs 0.9-1.4), a narrower lip region (16-19 vs 20-23 μm), wider mid-body (53-69 vs 39-57 μm), longer spicules (53-69 vs 45-53 μm), and fewer supplements (7-11 vs 11-17). Longidorus ferrisi n. sp. differs from L. milanis by a longer body (4.33-5.97vs 3.00-4.90 mm), a greater c value (111-187 vs 86-130), a wider mid-body (53-69 vs 43-56 μm), a different head shape, and longer spicules (53-69 vs 41-54 μm). The nuclear 18S ribosomal DNA sequence of this species revealed that this species is unique with respect to all sequenced Longidorus species. 相似文献
999.
Dongmei Yin Sumei Chen Fadi Chen Zhiyong Guan Weimin Fang 《Environmental and Experimental Botany》2009,67(1):87-93
Responses to waterlogging of a tolerant chrysanthemum cultivar (‘53-4’) were compared with those of a susceptible one (‘13-13’). Just 4 days of waterlogging were enough to induce wilting and leaf chlorosis in ‘13-13’, but there was no visual damage to the leaves of ‘53-4’ after 8 days of treatment. After 20 days, only a small number of adventitious roots had emerged from ‘13-13’ stems, but many vigorous adventitious roots had formed in ‘53-4’. Waterlogging induced increases in the activity of alcohol dehydrogenase (EC 1.1.1.1), pyruvate decarboxylase (EC 4.1.1.1) and lactate dehydrogenase (EC 1.1.1.27) in both cultivars, but the increases in ‘13-13’ were more pronounced than in ‘53-4’. On the other hand, the activity of superoxide dismutase (EC 1.15.1.1), ascorbate peroxidase (EC 1.11.1.11) and catalase (EC 1.11.1.6) was higher in ‘53-4’ than in ‘13-13’. Leaves of ‘13-13’ had a higher content of malondialdehyde, and the amount of this stress indicator in ‘53-4’ was stable throughout the waterlogging period. Ethylene production was enhanced by waterlogging in both cultivars, but peak ethylene production occurred 2 days earlier in the tolerant cultivar, and was 3-fold higher than in the susceptible one. 相似文献