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41.
目的探讨急性阑尾炎多层螺旋CT征象与血清炎性标志物的关系。方法收集2012年1月至2013年12月于同济大学附属杨浦医院经手术病理证实的具有完整临床及影像资料的急性阑尾炎患者66例,对所有患者的急性阑尾病变程度行CT分级,分析其与患者白细胞(WBC)计数、中性粒细胞百分比(NEUT%)及血清C反应蛋白(CRP)水平的相关性。结果急性阑尾炎CT分级与患者WBC计数与CRP水平呈正相关(P0.05),穿孔性阑尾炎患者NEUT%及CRP水平明显高于其他患者。CRP水平与阑尾直径、阑尾积液、回盲部变化、阑尾周围炎性条纹、小肠积液呈正相关(P0.05),WBC计数与回盲部变化及阑尾周围炎性条纹呈正相关(P0.05)。结论WBC计数及CRP水平与急性阑尾炎CT分级有关,CRP对急性阑尾炎的诊断及其严重程度的判断更有优势;CRP、NEUT%是穿孔性阑尾炎的重要预测因子,WBC可以更好地发现早期阑尾周围的炎性反应,综合分析CT表现与血清炎性标志物能更准确地诊断急性阑尾炎。  相似文献   
42.
The gamma-aminobutyric acid antagonist, bicuculline methiodide (BMI), induces myoclonic seizures in rats when injected into the deep prepyriform cortex at concentrations lower than those that induce convulsions from the amygdala, hippocampus, or neocortex. This observation prompted the suggestion that the deep prepyriform cortex was responsible for seizure generation regardless of the neurotransmitter and neuronal circuits involved. Bilateral intrastriatal application of BMI protects rats against seizures induced by (i) local application of BMI into the deep prepyriform cortex and (ii) systemic application of bicuculline, pilocarpine (a cholinergic agonist), or kainic acid (a glutamate receptor agonist). The region of the striatum sensitive to the previously unknown anticonvulsant action of BMI is located in the immediate vicinity of the deep prepyriform cortex and is 100-150 times more sensitive to the anticonvulsant action relative to the sensitivity of the deep prepyriform cortex to the convulsant action of BMI. These data suggest a powerful gamma-aminobutyric acid-dependent gating role of the basal ganglia in determining the seizure threshold in the forebrain. This argues against the suggestion that the deep prepyriform cortex plays a crucial role in the generation of seizures following systemic administration of convulsants. The discovery of an anticonvulsant action of BMI in the rat striatum contradicts the gamma-aminobutyric acid theory of epilepsy, which implies that deficits in the gamma-aminobutyric acid-mediated inhibition in the central nervous system lead to the emergence of seizures.  相似文献   
43.
Not only does breast milk provides an ideal nutrient composition for the newborn, but it also contains a variety of substances that may actively influence growth and development of the infant and stimulate neonatal protection against gastrointestinal diseases. Hormones, growth factors, cytokines and even whole cells are present in breast milk and act to establish biochemical and immunological communication between mother and child. In addition, milk nutrients such as nucleotides, glutamine and lactoferrin have been shown to influence gastrointestinal development and host defense. The unique properties of milk as a mediator of biochemical messages will be presented and the clinical significance of breastfeeding in the prevention of neonatal gastrointestinal diseases will be discussed.  相似文献   
44.
Previously we have described the properties of store-operated channel currents (SOCs) in freshly dispersed rabbit portal vein smooth muscle cells. In addition to Ca2+ store depletion these SOCs could also be activated by α-adrenoceptor stimulation and diacylglycerol (DAG) via a protein kinase C (PKC)-dependent mechanism. In the present study we have investigated the effect of β-adrenoceptor stimulation on SOCs in rabbit portal vein myocytes. With whole-cell recording the selective β-adrenoceptor agonist isoprenaline reduced the current evoked by cyclopiazonic acid (CPA, sarcoplasmic/endoplasmic reticulum ATPase inhibitor) by over 85%. With cell-attached patch recording, bath application of isoprenaline produced a pronounced inhibition of SOC activity evoked by either CPA or the acetoxymethyl ester form of BAPTA (BAPTA-AM). SOC activity evoked by CPA, the DAG analogue, 1-oleoyl-acetyl- sn -glycerol (OAG) or the phorbol ester, phorbol-12,13-dibutyrate (PDBu) was also markedly inhibited by the adenylate cyclase activator, forskolin, and the cell-permeable non-hydrolysable analogue of cyclic adenosine monophosphate (cAMP), 8-Br-cAMP. With inside-out patches, bath application of PDBu evoked channel currents with similar properties to SOCs which were inhibited by over 90% by a catalytic subunit of protein kinase A (PKA) and by 8-Br-cAMP. Moreover bath application of PKA inhibitors, H-89, KT5720 and an inhibitory peptide to quiescent cell-attached or inside-out patches, activated channel currents with similar properties to SOCs. These data suggest that in rabbit portal vein myocytes, stimulation of β-adrenoceptors inhibits SOC activity via a cAMP-dependent protein kinase signal transduction cascade. In addition it is concluded that constitutive PKA activity has a profound inhibitory effect on SOC activity in this vascular preparation.  相似文献   
45.
目的:研究低氧时小鼠肺组织中低氧诱导因子-1α(HIF-k)表达的变化。方法:实验用雄性小鼠,低氧仓浓度分别为10%、7%、5%。用免疫荧光组织化学技术及共聚焦显微术,检测小鼠在低氧条件下肺组织中HIF-1α表达的变化。结果:正常组小鼠肺组织HIF-1α无表达,低氧组HIF-1α表达增加,且随低氧时间的延长及低氧强度的增加而增强。结论:低氧可诱导小鼠肺组织中HIF-1α的表达增强,(HIF-k)可能参与肺组织细胞凋亡的发生。  相似文献   
46.
The aim of this study is to investigate whether three mononucleotide polymorphisms at the locus -1082,-819 and -592 in the promoter region of the IL-10 gene are associated with chronic severe hepatitis. The IL-10-592 and IL-10-1082 polymorphisms were genotyped by polymerase chain reactionrestriction fragment length polymorphism analysis (PCR-RFLP) while polymerase chain reaction-sequence specific primer (PCR-SSP) assay was used to test the IL-10-819 polymorphism. The polymorphisms of IL-10-1082, -819 and -592 genes were detected in 98 patients with chronic severe hepatitis (CSH), 478 patients with chronic hepatitis B (CHB), 223 asymptomatic (chronic) HBV carriers (ASC) and 267 patients with self-restricted HBV. There was significant difference of the polymorphisms of IL-10-1082, IL-10-819 and IL-10-592 genes between CSH group and other groups. The frequency of AA genotype at IL-10 gene promoter -1082 locus in chronic severe hepatitis patients was higher than that in asymptomatic HBV carriers (2 = 13. 314, P = 0.001), and self-restricted HBV patients (χ^2 = 13.545, P = 0.000); the frequency of CC and AC genotype at IL-10 gene promoter -592 locus in chronic severe hepatitis patients was higher than that in chronic hepatitis patients(χ^2 = 15.970, P=0.000) (χ^2 =20.414, P=0.000), asymptomatic HBV carriers (χ^2 =21.283, P= 0.000) (χ^2 = 28.309, P = 0.000) and self-restricted HBV patients(χ^2 = 17.047, P = 0.000) (χ^2 = 16.528, P = 0.000) ; the frequency of TC genotype at IL-10 gene promoter -819 locus in chronic severe hepatitis patients was higher than that in chronic hepatitis patients(χ^2 = 58.961, P = 0.000), asymptomatic HBV carriers ( χ^2 = 53. 255, P = 0. 001 ) and self-restricted HBV patients (χ^2 = 39.616, P = 0.001). So interleukine-10 gene polymorphism was associated with the chronic severe hepatitis.  相似文献   
47.
目的为斜坡区肿瘤手术提供解剖资料。方法20例整颅,10例行水平切面,10例行正中矢状切面。测量切牙孔、前鼻棘、后鼻棘、枕骨大孔前端、枕髁前端、卵圆孔、破裂孔、颈动脉管外口及舌下神经管外口的内侧缘至咽结节的距离;测量卵圆孔、破裂孔、颈动脉管外口及舌下神经管外口的内侧缘至正中线的距离;测量枕骨基底部颅底外面的长径、枕骨大孔纵径(FML)、枕骨大孔前正中点与枕髁后缘连线垂直距离(AOCP)、枕髁轴径(OCA)、枕髁间距。结果切牙孔后缘、前鼻棘、后鼻棘、枕骨大孔前端、枕髁前端、卵圆孔、破裂孔、颈动脉管外口及舌下神经管外口的内侧缘至咽结节的距离分别为(mm):72.12±4.25、77.77±3.89、33.73±2.07、13.14±1.91、15.71±1.74、27.51±2.12、15.98±1.98、25.93±2.23、19.15±1.49。卵圆孔、破裂孔、颈动脉管及舌下神经管外口的内侧缘至中线的距离分别为:25.55±1.63、11.72±1.70、25.75±1.98、17.41±1.41。枕骨基底部颅底外面长径、FML、AOCP、OCA、枕髁间距分别为(mm):28.80±2.67、35.84±2.59、17.10±1.13、24.55±2.35、21.07±1.92。结论经口咽至斜坡区的手术入路中,开骨窗时安全范围是以咽结节为中心,以15mm为半径做斜坡磨除;也可以做矩形骨窗,即以咽结节为中心开一长(高)25mm×宽20mm的骨窗。  相似文献   
48.

Background  

Genetic polymorphisms of the TCF7L2 gene are strongly associated with large increments in type 2 diabetes risk in different populations worldwide. In this study, we aimed to confirm the effect of the TCF7L2 polymorphism rs7903146 on diabetes risk in a Brazilian population and to assess the use of this genetic marker in improving diabetes risk prediction in the general population.  相似文献   
49.
T cell cytokine expression may be induced by the cytokine IL-2 or via the TCR complex. The comparative effects of cytokine- and TCR-mediated signalling on the induction of human IL-5 mRNA were examined. Cytokine mRNA expression was analysed by RT-PCR in fresh peripheral blood mononuclear cells (PBMC) from normal individuals and in populations of activated T lymphocytes, derived from phytohaemagglutinin (PHA)- stimulated PBMC. rIL-2 induced IL-5 expression in PBMC, the kinetics of which were similar to the effects of PHA. rIL-4 induced IL-5 mRNA expression in activated T lymphocytes. IL-5 expression induced by either IL-2 or PHA was completely abolished by the protein synthesis inhibitor cycloheximide. rIL-2-induced IL-5 expression was resistant to cyclosporin A (CsA), whereas IL-5 expression elicited by PHA was inhibited by CsA, at doses as low as 10 ng/ml. Rapamycin (RAP) had no effect on rIL-2-stimulated IL-5 expression, but suppressed IL-5 expression induced by PHA. The inhibitory effect of RAP on PHA-induced IL-5 expression was more apparent at 12 and 24 h after stimulation than at earlier times. The resistance of IL-2 receptor (IL-2R) signalling to CsA and RAP indicates that the IL-2R and the TCR are associated with different pathways regulating IL-5 expression.   相似文献   
50.
[目的]用荧光DDRT-PCR技术寻找低剂量环境化学污染物(ECPs)过氧化氢(H_2O_2)、甲醛(FA),三氯乙烯(TCE)诱导细胞适应性反应差异表达的基因,为进一步研究低剂量的环境化学污染物(ECPs)诱导机体的生物学效应及其机理提供科学依据。[方法]依据H_2O_2、FA、TCE对细胞毒性的剂量反应关系,建立适应性反应的模型。然后用荧光DDRT-PCR寻找对照组、低剂量组、高剂量组,适应性反应组差异表达的基因,并鉴定和验证部分差异表达的基因。[结果]按照对照组、低剂量组、高剂量组、适应性反应组处理细胞后,DDRT-PCR结果显示各处理组与对照组比较:H_2O_2有60个差异条带、FA有61个,TCE有52个。选择差异比较明显的条带进行2次PCR,然后通过进一步克隆、测序、同源性比较发现一些已知基因如BCL-2、EIF3S5、NDUFS4、RPS10等。[结论]低剂量环境化学污染物诱导机体的适应性反应可能有维持细胞稳态、抗氧化系统、DNA损伤修复级激活细胞信号分子等过程的参与。  相似文献   
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