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31.
生大黄粉灌肠在重症急性胰腺炎治疗中的临床价值 总被引:4,自引:0,他引:4
目的 探讨善宁联合大黄对急性重症胰腺炎的治疗效果.方法 将40例急性重症胰腺炎患者随机分为二组:治疗组20例,为善宁联合大黄治疗组;对照组20例,为善宁治疗组.观察患者治疗前后血清炎症因子TNFa、IL-1b水平、血淀粉酶、血脂肪酶、血白细胞计数及腹部症状缓解情况.结果 治疗组血清TNFα、IL-1b、血淀粉酶、血脂肪酶及血白细胞计数下降水平及腹部症状缓解情况明显好于对照组.结论 中药大黄能明显促进胃肠道功能恢复,减少肠道细菌移位,减轻急性炎症反应综合征,减轻胰腺损害,促进胰腺修复,提高疗效,缩短疗程.联合应用善宁和大黄治疗急性重症胰腺炎可提高治疗效果,缩短住院天数. 相似文献
32.
Ivan Pavlov Leonid P. Savtchenko Inseon Song Jaeyeon Koo Alexey Pimashkin Dmitri A. Rusakov Alexey Semyanov 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(1):504-509
The spiking output of interneurons is key for rhythm generation in the brain. However, what controls interneuronal firing remains incompletely understood. Here we combine dynamic clamp experiments with neural network simulations to understand how tonic GABAA conductance regulates the firing pattern of CA3 interneurons. In baseline conditions, tonic GABAA depolarizes these cells, thus exerting an excitatory action while also reducing the excitatory postsynaptic potential (EPSP) amplitude through shunting. As a result, the emergence of weak tonic GABAA conductance transforms the interneuron firing pattern driven by individual EPSPs into a more regular spiking mode determined by the cell intrinsic properties. The increased regularity of spiking parallels stronger synchronization of the local network. With further increases in tonic GABAA conductance the shunting inhibition starts to dominate over excitatory actions and thus moderates interneuronal firing. The remaining spikes tend to follow the timing of suprathreshold EPSPs and thus become less regular again. The latter parallels a weakening in network synchronization. Thus, our observations suggest that tonic GABAA conductance can bidirectionally control brain rhythms through changes in the excitability of interneurons and in the temporal structure of their firing patterns.Rhythmic activity paces signal transfer within brain circuits. Brain rhythms are believed to depend heavily on the networks of inhibitory interneurons (1–4). In addition to synaptic inputs, interneuron excitability in the hippocampus is determined by tonic GABAA conductance (5, 6), which could thus contribute to hippocampal rhythmogenesis. Indeed, GABA transaminase inhibitor vigabatrin increases the ambient GABA concentration, enhancing the power of the theta-rhythm in rats (7). In mice expressing GFP under the GAD67 promoter the reduced levels of ambient GABA correlate with a decreased power of kainate-induced oscillations in vitro (8). The latter decrease is reversed by a GABA uptake inhibitor, guvacine, which raises ambient GABA. GABA release by astrocytes also increases the gamma oscillation power in hippocampal area CA1 in vivo (9). Intriguingly, in hippocampal slices of animals lacking δ subunit-containing GABAA receptors (which mediate tonic conductance in many local cell types including interneurons) the average frequency of cholinergically induced gamma oscillations is increased, whereas the oscillation power tends to drop (10). However, cellular mechanisms underlying such phenomena remain poorly understood.One possible explanation is the influence of tonic GABAA conductance on the firing pattern of interneurons. Activation of GABAA receptors inhibits most neurons, through either membrane hyperpolarization or shunting or both (11). In the adult brain, a depolarizing action of GABA has also been reported in various cell types, including hippocampal interneurons (3, 12–15). GABAergic depolarization can prompt spike generation, thus countering the shunting effects (14, 16). Therefore, experimental evidence indicates that the net effect of GABAA receptor activation combines the excitatory action of depolarization and the inhibitory consequences of shunting, with the latter prevailing when the GABAA receptor conductance is sufficiently strong. As a result, increasing the tonic GABAA signaling can have a biphasic effect on individual hippocampal interneurons: excitatory at weak conductances and inhibitory at strong (14). Here we find that weak tonic GABAA conductance favors a more regular firing pattern of interneurons, thus facilitating synchronization of the CA3 network. In contrast, strong GABAA conductance makes the firing pattern more dependent on the stochastic excitatory synaptic input, thus reducing network synchrony. 相似文献
33.
HBV感染血清标志物、HBV DNA水平与性别的关系 总被引:9,自引:0,他引:9
探讨HBV感染者血清标志物、HBVDNA水平和性别之间的关系.选择495例HBsAg阳性的血清标本和502例HBV DNA高于1×108copy/ml以上的血清标本,分别通过ELISA法以及实时荧光定量法进行HBV感染血清标志物HBV DNA的检测.三种组合[组合1为HBsAg( )HBeAg( )抗-HBc( ),组合2为HBsAg( )抗-HBe( )抗-HBc( ),组合3为HBsAg( )抗-HBc( )]的HBV DNA阳性率(分别为95%、18%和53%)存在极显著差异(P<0.01);女性在HBAg阴性模式中的比例与在HBeAg阳性模式中的比例差异显著(P<0.05).HBV感染血清标志物、HBV DNA水平和性别之间存在着重要的关系;对于组合3的患者要给予足够重视;女性在高HBV DNA水平而且HBeAg阴性组合中的比例非常小,这也许与女性在肝癌患者中所占比例较低存在着一定的关系. 相似文献
34.
[目的]探讨抗凝血素抗体(anti- prothrombin antibodies aPT)与自身免疫性自然流产关系及其诊断价值 .[方法]通过病例对照研究的方法,用酶联免疫吸附实验(ELISA)检测60名有自然流产的患者(研究组)及20名正常妇女(对照组)的血清中抗凝血素抗体(aPT)IgG、IgM水平,同时与抗心磷脂抗体ACA的检测相比较.[结果]①研究组aPT-IgG和IgM浓度分别为6.71±2.11 U/ml 和5.30±1.71 U/ml;对照组aPT-IgG和IgM浓度分别为4.48±1.42 U/ml和4.00±1.11 U/ml,研究组aPT-IgG和IgM浓度水平均显著高于对照组 (P<0.01).②研究组aPT阳性率为35.00%,对照组为5.00%,两组比较差异有统计学意义(P=0.021,P<0.05),研究组ACA阳性率为65.00%,对照组为15.00%,两组比较差异有显著性(P<0.01).aPT阳性率、敏感度、准确度及误诊率(假阳性率)均低于ACA,而aPT特异度、漏诊率(假阴性率)高于ACA.[结论]①aPT 与自身免疫性自然流产有关.②aPT可在自身免疫性自然流产及APS诊断过程中作为辅助诊断指标,但aPT的敏感度低,漏诊率高,故它的临床应用价值有待于进一步研究. 相似文献
35.
Objective To investigate the effect of angiotensin (Ang) Ⅱ and its Janns-activated kinase-2 (JAK2) signal pathway in transdifferentiation of renal tubular cells under the challenge of acute ischemic reperfusion injury.Methods Models of acute ischemic reperfusion injury were established and the level of local Ang Ⅱ ,a key element of renin-angiotensin system (RAS),in kidney was measured using radioimmunity technique.The expression of α-smooth muscle actin (α-SMA),a phenotype of mesenchymal cells,was detected by RT-PCR and inununohistochemistry methods.Renal tubule cells ( NRK-52E) were cultured with various concentration of Ang Ⅱ ,followed by blocking of PD123319,Ang U receptor 2 antagonist,and AG490,an inhibitor of JAK2 signal pathway.Results Ang 0 of kidney tissue increased immediately after acute ischemic-reperfusion injury,in time dependent fashion.Expression of α-SMA in renal tubule cells was found at 48 hours after ischemic-reperfusion injury and in NRK-52E cells treated by high concentration of Ang Ⅱ and was dose and time dependent.The peak of α-SMA expression was seen after 30 minute treatment at the dose of 10-9'mol/L,which was interrupted by both of PD123319 and AG490.Conclusions Transdifferentiarion of renal tubular epithelial cells occurs under acute ischemic- reperfusion injury.Local renin-angiotensin system may play a role in the transdifferentiation of TEC through AT2 receptor and its JAK2 signal pathway. 相似文献
36.
SARS患者恢复期血清中特异性抗体保护作用的研究 总被引:3,自引:1,他引:3
目的 观察半年恢复期严重急性呼吸综合征 (SARS)患者血清中 SARS抗体对 SARS病毒介导细胞病变的抑制作用。方法 用酶联免疫吸附试验 (EL ISA)测定 12例 SARS恢复期患者血清中 SARS抗体 (Ig G)的吸光度 (A)值 ;用维持液按 1∶ 8稀释恢复期患者的血清 ,并与分离、培养和鉴定后不同稀释度的SARS病毒 (SARS Co )上清作用 ,再加入 Vero E6细胞悬液进行培养 ,观察 Vero E6细胞病变的程度。结果 12例恢复期患者半年前的 SARS抗体 A值范围为 0 .79~ 2 .0 1,半年后的 A值范围为 0 .81~ 2 .0 6。其加入 12例恢复期血清的 SARS Co Vero E6细胞病变程度至少降低 2 5 %以上。结论 SARS患者半年后恢复期血清的 SARS抗体滴度有上升趋势 ,它还可抑制 SARS病毒介导的细胞病变 ,对 SARS病毒有中和作用 ,推测 SARS抗体是一种保护性抗体 相似文献
37.
目的调查胸部手术患者术前睡眠情况及相关因素.方法采用匹兹堡睡眠质量指数问卷调查了51例胸部全身麻醉手术患者术前睡眠情况,并记录了影响患者睡眠的前三位影响因素.结果有28例患者有睡眠质量问题,占54.9%,有16例(31.4%)可疑有睡眠质量问题31.4%.结论胸部手术患者术前睡眠质量问题比较普遍,可能的影响因素为不清楚疾病诊断,对手术和全麻恐惧,担心术后康复,为费用发愁. 相似文献
38.
Objective To investigate the effect of angiotensin (Ang) Ⅱ and its Janns-activated kinase-2 (JAK2) signal pathway in transdifferentiation of renal tubular cells under the challenge of acute ischemic reperfusion injury.Methods Models of acute ischemic reperfusion injury were established and the level of local Ang Ⅱ ,a key element of renin-angiotensin system (RAS),in kidney was measured using radioimmunity technique.The expression of α-smooth muscle actin (α-SMA),a phenotype of mesenchymal cells,was detected by RT-PCR and inununohistochemistry methods.Renal tubule cells ( NRK-52E) were cultured with various concentration of Ang Ⅱ ,followed by blocking of PD123319,Ang U receptor 2 antagonist,and AG490,an inhibitor of JAK2 signal pathway.Results Ang 0 of kidney tissue increased immediately after acute ischemic-reperfusion injury,in time dependent fashion.Expression of α-SMA in renal tubule cells was found at 48 hours after ischemic-reperfusion injury and in NRK-52E cells treated by high concentration of Ang Ⅱ and was dose and time dependent.The peak of α-SMA expression was seen after 30 minute treatment at the dose of 10-9'mol/L,which was interrupted by both of PD123319 and AG490.Conclusions Transdifferentiarion of renal tubular epithelial cells occurs under acute ischemic- reperfusion injury.Local renin-angiotensin system may play a role in the transdifferentiation of TEC through AT2 receptor and its JAK2 signal pathway. 相似文献
39.
2型糖尿病下肢血管病变超声诊断的临床应用价值 总被引:2,自引:0,他引:2
目的:评价彩色多普勒超声对2型糖尿病(DM)下肢血管病变(LEAD)的诊断应用价值。方法:2型DM患者91例与41例同期住院非2型DM患者进行下肢血管彩色多普勒超声检查对照,并以踝肱压指数(ABPI)对比观察。结果:2型DM动脉硬化为弥漫性或多节段病变,单纯动脉硬化多为血管分叉处局灶性病变,2型DM患者下肢血管管腔的硬化斑块、狭窄、闭塞的发生率明显高于对照组,呈显著性差异(P<0.01)。硬化斑块的发生率以股动脉最常见,而管腔狭窄、闭塞率以累及腘动脉以下的远端动脉血管多见,胫前动脉受累最为明显(P<0.05)。结论:彩色多普勒超声是2型DM患者下肢血管病变检查的有效手段,可评估病变部位、阻塞的性质、病变长度以及解剖的异常,对早期诊断、预防及治疗具有重要的临床应用价值。 相似文献
40.