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排序方式: 共有485条查询结果,搜索用时 15 毫秒
101.
目的:研究川崎病患儿血浆中可溶性内皮细胞蛋白C受体(s EPCR)、一氧化氮(NO)的表达及与炎症反应和冠状动脉病变(CAL)的关系。方法:选择2016年12月至2018年2月盘锦市中心医院收治的川崎病患儿104例为川崎病组,根据患儿彩色超声心动图检测结果将川崎病组分为CAL组30例和非CAL组(NCAL组)74例。另选取同期于我院进行体检的健康儿童56例为对照组。比较川崎病组与对照组、川崎病组患儿急性期与缓解期、CAL组与NCAL组s EPCR、NO、C-反应蛋白(CRP)、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平,并分析川崎病患儿s EPCR、NO与炎症因子及CAL的相关性。结果:川崎病组患儿s EPCR、NO、CRP、IL-6、TNF-α水平均高于对照组,差异有统计学意义(P0.05)。川崎病组患儿急性期s EPCR、NO、CRP、IL-6、TNF-α水平均高于缓解期,差异有统计学意义(P0.05)。CAL组s EPCR、NO、CRP、IL-6、TNF-α水平均高于NCAL组,差异有统计学意义(P0.05)。经Pearson相关性分析结果显示,川崎病患儿s EPCR、NO与CRP、IL-6、TNF-α及CAL均呈正相关(P0.05)。结论:川崎病患儿s EPCR、NO水平与炎性因子及CAL相关,s EPCR、NO可能在其炎症反应及CAL进展中起到一定的作用。  相似文献   
102.
Abstract: To examine the role of nerve-specific (Na+, K+)-ATPase in chronic changes in noradrenergic activity, we examined the effects of noradrenergic denervation and hyperinnervation on p -nitrophenylphosphatase activity and on total and nerve-specific ouabain binding. High-affinity and erythrosin B-sensitive binding were compared as measurements of nerve-specific binding. Hyperinnervation and denervation was produced in cerebellum and cerebral cortex, respectively, by 6-hydroxydopamine lesions of the dorsal noradrenergic bundle. Hyperinnervation increased, and denervation decreased, enzyme activity, high-affinity ouabain inhibition, and erythrosin B-sensitive ouabain binding. As (Nat+, K+)-ATPase has a major role in the regulation of neural excitability and energy metabolism, and the ouabain binding site has been shown to have endogenous ligands, these changes in (Na+, K+)-ATPase may be important in the long-term regulation of neuron function by norepinephrine.  相似文献   
103.
目的:探讨胚胎型大脑后动脉(Fetal origin of the posterior cerebral artery,FTP)与脑白质病之间的关系。方法:收集2013年1月~2014年6月在我院住院患者共485例,所有患者均行头颅磁共振平扫及血管成像,观察脑白质病变、急性脑梗死及FTP存在与否,并分为观察组(脑白质病组)和对照组(无脑白质病组),比较FTP的发生率。结果:观察组和对照组分别为232例和253例,观察组共发现53例FTP患者(左侧、右侧、双侧FTP分别为15例、19例、19例),FTP总发生率为22.8%,左侧、右侧、双侧FTP发生率分别为6.5%、8.2%、8.2%;对照组98例FTP患者(左侧、右侧、双侧FTP分别为26例、44例、28例),FTP总发生率为38.7%,左侧、右侧、双侧FTP发生率分别为10.3%、17.4%、11.1%,观察组FTP总发生率及右侧FTP发生率明显低于对照组(P0.001和P0.01)。232例观察组中急性脑梗死患者共156例,无急性脑梗死患者76例,其中急性脑梗死组有28例FTP患者(左侧、右侧、双侧FTP分别为7例、15例、6例),FTP总发生率及左侧、右侧、双侧FTP发生率分别为17.9%、4.5%、9.6%、3.8%;而无急性脑梗死的患者中,有24例FTP患者(左侧、右侧、双侧FTP分别为8例、4例、12例),FTP总发生率及左侧、右侧、双侧FTP发生率分别为31.6%、10.5%、5.3%、15.8%,观察组FTP总发生率及双侧FTP发生率明显低于对照组(P0.05和P0.01)。结论:FTP的存在可能一定程度上降低脑白质病甚至脑梗死的发生。  相似文献   
104.
DNA replication is a fragile process, since unavoidable lesions in the template DNA cause replicative polymerases to stall, posing a serious threat to genome integrity. Homologous recombination, translesion DNA synthesis and de novo reinitiation of DNA synthesis ensure robust replication by navigating it passed damaged DNA. In this review, we highlight the relationship between these three processes.  相似文献   
105.
Maseki T  Tanaka H 《Gerodontology》2006,23(3):183-186
Objectives: Clinically non‐carious cervical lesions (NCCLs) are frequently seen. The aim of this study was to investigate the relationship between the shape and symmetry of NCCLs, wear of cuSPS and triangular ridge, and the curvature of the tooth root. Methods: One hundred and twenty‐nine extracted human upper canine teeth and 274 extracted human upper premolar teeth with NCCLs were used in this study. The specimens were studied using photographs and three‐dimensional scanning. Results: Asymmetric NCCL was observed in 69.0% of the canines and 44.5% of the premolars. Wear of cusp and lingual ridges was observed in 82.9% and 93.0% of the canines, respectively. Wear of the buccal cusp and buccal triangular ridge was observed in 85.4% and 89.8% of the premolars, respectively. On the other hand, the wear of lingual cusp and lingual triangular ridge was observed in 89.1% and 93.8% of the premolars, respectively. The curvature of the root was observed in 48.1% of the canines and 43.4% of the premolars. Conclusions: There was no relationship between the symmetry of NCCLs, and the wear of cuSPS and triangular ridges for either canines or premolars. Although there was a relationship (p < 0.05) between the symmetry of NCCL and the curvature of the root in the canines, no relationship was observed between the symmetry of NCCL and the curvature of the root in the premolars.  相似文献   
106.
目的:探讨色素内镜(CE)、窄带成像内镜(NBI)对大肠平坦型病变的检出及相关因素。方法:对2010年4月至6月来我院国际医学中心的276例患者行结肠镜检查,262例患者入选。先行常规白光模式插镜至回盲部,应用NBI模式退镜观察,检出平坦型病变后记录病变特征(包括数量、部位、形态、大小),然后再在常规白光模式下插镜至回盲部,应用0.25%靛胭脂染色后行色素内镜退镜观察,检出平坦型病变后记录病变特征,最后于病变活检。比较CE和NBI对平坦型病变的检出并分析相关因素。结果:262例患者中,共计检出病变198个,其中平坦型病变69个,检出率为34.8%。NBI检出平坦型病变51个(73.9%);CE检出平坦型病变69个(100%)(P<0.05)。NBI漏诊了18个平坦型病变,漏诊率为26.1%。NBI检出的平坦型病变平均大小为8.7±2.6mm,CE检出的平坦型病变平均大小为4.5±2.1mm(P<0.05)。NBI检出<5mm的平坦型病变5个(7.2%),CE检出<5mm的平坦型病变19个(27.5%)(P<0.05)。NBI检出的IIc型平坦型病变13个(18.8%),CE检出的IIc型平坦型病变25个(36...  相似文献   
107.
Present study deals with improvement in conventional technique of spraying liquid nitrogen on cancerous lesions to improve its efficacy. It is an attempt to demarcate the variation in outcome when cryogen is sprayed through customised multi-hole nozzle (MHN). Influence of mass flow rate on cryoablation while varying the number of holes in MHNs is analysed experimentally. Another section of study focuses on the impact of the rate of evaporation of cryogen when margin among the holes is changed. Total 6 MHNs are fabricated while changing their geometrical parameters. Single freeze-thaw cycle is carried out to spray liquid nitrogen on tissue mimicking gel with a spraying distance of 18 mm. Temperature profile captured through infrared images advocates that lethal area formed through the application of MHNs with 5 holes is larger than MHNs with 4 holes on the surface of gel. It reflects the influence of central hole on necrosis. In order to necrotize lesion through freezing, the most desired cooling rate (CR) varies from 50C/min to 200C/min. It is achieved up to a depth of 2 mm below the gel surface and in a radius of 10 mm from the centre of spray (CS) for all MHNs, except 4C. Most optimised margin in terms of cryoablation is also estimated in the study. MHN with 1.5 mm margin provides the most optimised results in terms of cryoablation when MHNs with the central hole are considered while MHN with 1 mm margin provides most optimised result when MHNs without central hole are considered. On the basis of observations made through thermal images it can be said that multiple freezing fronts are not observed on the gel surface which aids in the formation of lone giant ice ball. This provides an extra edge to the treatment methodology because alteration in the dimensions of necrotic zone can be made by changing the duration of spray. Larger lateral spread of necrotic zone will also reduce the number of sittings required for the treatment of larger lesions.  相似文献   
108.
109.
The amygdala and autism: implications from non-human primate studies   总被引:4,自引:0,他引:4  
Brothers (1990 ) has proposed that the amygdala is an important component of the neural network that underlies social behavior. Kemper and Bauman (1993 ) identified neuropathology in the amygdala of the postmortem autistic brain. These findings, along with recent functional neuroimaging data, have led Baron-Cohen et al. (2000 ) to propose that dysfunction of the amygdala may be responsible, in part, for the impairment of social behavior that is a hallmark feature of autism. Recent data from studies in our laboratory on the effects of amygdala lesions in the adult and infant macaque monkey do not support a fundamental role for the amygdala in social behavior. If the amygdala is not essential for the component processes of social behavior, as seems to be case in both non-human primates and selected patients with bilateral amygdala damage, then it is unlikely to be the primary substrate for the impaired social behavior of autism. However, damage to the amygdala does have an effect on a monkey's response to normally fear-inducing stimuli, such as snakes, and removes a natural reluctance to engage novel conspecifics in social interactions. These findings lead to the conclusion that an important role for the amygdala is in the detection of threats and mobilizing an appropriate behavioral response, part of which is fear. Interestingly, an important comorbid feature of autism is anxiety ( Muris et al. 1998 ). If the amygdala is pathological in subjects with autism, it may contribute to their abnormal fears and increased anxiety rather than their abnormal social behavior.  相似文献   
110.
Correspondence analyses were used to explore the relationships between yield and populations of Pratylenchus zeae in an upland rice field and in a greenhouse experiment. Initial soil (Pi) and final root (Pf) population densities of P. zeae, and yield (Y) of rice cv. UPL Ri5 were determined at 490 spots in the field. Very low Y was linked to very high Pf. Low Y was linked to medium or high Pi and medium Pf. Medium to very high Y were clustered with undetectable Pi and very low or high Pf. All yield levels were independent of very high Pi. In the greenhouse experiment where seven nematode inoculum levels and three fertilizer levels were evaluated, low Y was associated with medium or high Pf and high Y with high or low Pf. The analyses indicated that nematode-yield interaction involved a complex, dynamic process, in which the root-carrying capacity probably was a determining factor. Correspondence analysis, which does not require assumptions on the shape of nematode population-yield relationships or on variable distributions, revealed meaningful associations in these complex data sets.  相似文献   
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