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91.
Andre P. Boezaart 《Journal canadien d'anesthésie》1989,36(6):697-700
A 23-year-old primigravid patient who received epidural analgesia for pain of labour presented with persistent, apparently irremediable, unilateral analgesia. Computerized axial tomo-epidurography demonstrated absence of circumferential spread due to lateral placement of the catheter. Transforaminal escape of contrast medium into the paravertebral area had occurred and anterior and posterior midline partitioning of the epidural space was obvious. All the usual measures to promote contralateral analgesia, except re-insertion of the catheter, had been tried without success. 相似文献
92.
CPP-SOM整合cDNA基因芯片平台的建立 总被引:2,自引:0,他引:2
目的 在转录组水平全面迅速地了解疾病发生和药物作用的分子机理 ,以及寻找潜在的治疗靶标。方法 通过建立基因芯片平台 ,用全反式维甲酸诱导急性早幼粒细胞白血病来源的 NB4细胞分化作为模型 ,并应用自主开发的自组织图结合成分平面展示 (componentplane presentation integrated self-organizing map,CPP- SOM)的方法对数据进行初步分析。结果 建立的 c DNA芯片共有 12 6 30条克隆 ,其中已知基因 94 36条。应用该芯片进行实验 ,结果重复性好、准确性高。CPP- SOM不仅可以将功能相关的基因进行聚类 ,而且可以动态性地从全基因组水平观察药物作用过程中基因的表达变化。结论 我们建立的芯片平台是稳定、可靠的技术平台 ,CPP- SOM是一种新型有效的芯片数据的处理方法。 相似文献
93.
94.
目的 观察星状神经节阻滞对急性心肌梗死患者体内去甲肾上腺素(NE)、肾上腺素(adrenalin,ADR)、促肾上腺皮质激素(ACTH)、皮质醇(cortisol,ODR)等应激激素水平的影响。方法 选择已被确诊为急性心肌梗死患者68例,随机分为治疗组(34例)和对照组(34例).治疗组患者采用星状神经节阻滞治疗,两周为一疗程;对照组常规内科治疗。于阻滞前及阻滞后24、48、72、144h抽取静脉血标本。测定各时段的NE、肾上腺素、ACTH、皮质醇应激激素的含量。结果 阻滞后治疗组患者的NE、ADR、ACTH、ODR应激激素的含量与阻滞前及同时段的对照组比较有明显的降低,P〈0.05。结论 星状神经节阻滞可快速有效地缓解由于冠状动脉供血不足引起的缺血性疼痛,抑制应激反应,降低患者体内NE、ADR、ACTH、00R应激激素的水平。 相似文献
95.
In the identified neurons B1, B2 and B3 of Helix pomatia an intracellular injection of Na+ induced an outward current in 10% and an inward current in 90% of the experiments. The outward current was associated with an increase and the inward current with a decrease of the membrane conductance. Both currents reversed at membrane potentials of between -60 and -70 mV. Inward currents were also elicited by intracellular Li+ or tris-[hydroxymethyl]-aminomethane (Tris+) injection. All inward currents were reduced by extracellular administration of tetraethylammonium or quinine. It is suggested that the outward current represents a calcium-activated potassium current and that the inward current is due to a blockade of potassium channels from the intracellular side. 相似文献
96.
基于线性调频信号的高帧率超声成像系统 总被引:5,自引:0,他引:5
基于有限衍射波束的高帧率超声成像系统能实现快速成像,但由于仅通过一次发射事件成像,信噪比较低,本研究针对该问题提出一种改进方案。它采用合成孔径雷达中所使用的线性调频信号作为激励信号,在接收端则利用线性调频信号的脉冲压缩比等于信号的时间带宽积的特征,将接收信号通过匹配滤波器处理。结果表明该方案不仅能显著提高成像系统的信噪比,改善重构图像的质量,增加成像深度,而且不损失分辨率。 相似文献
97.
Wiebe R. Patberg Arie Nijmeijer Jan K. Schut Adrian Versprille Jacob P. Zock Willem G. Zijlstra 《Pflügers Archiv : European journal of physiology》1992,421(2-3):280-282
In ten vagus nerves the effect of local cooling on the compound action potential was studied in the temperature range of 34 to 0 °C in spontaneously breathing, anaesthetized rabbits. The mean temperature at which the myelinated (A) fibres were completely blocked, was 10.2±2.4 °C (mean ± S.D.). In nine nerves, local vagus cooling to 0 °C failed to block all non-myelinated (C) fibres. In one nerve, total blocking occurred at 2.0 °C. We conclude that in the rabbit, the earlier found increase in tonic activity of the diaphragm following lung inflation or deflation during bilateral local vagus cooling to a temperature between 8 and 0 °C is due to afferent impulses in vagal C fibres. 相似文献
98.
腹腔镜下左半结肠切除术相关筋膜平面的解剖观察 总被引:7,自引:2,他引:7
目的:探讨左半结肠切除术相关筋膜的解剖学特点和外科平面的鉴别方法。临床资料和方法:2003-2004年南方医院普通外科施行的腹腔镜左半结肠切除术15例,病例均为左半结肠癌。对腹腔镜下左半结肠后外侧、中线侧和直肠后外侧相关筋膜的解剖特点和镜下定位标志进行观察和描述。结果:在乙状结肠第一曲外侧缘肠壁与左侧腰大肌筋膜之间存在一个固定的粘连带,它是左侧Toldt’s线的尾侧端点。左半结肠系膜后外侧存在肾前筋膜;中线侧存在主动脉前筋膜;直肠系膜后外侧存在盆筋膜壁层。这三个部位的筋膜相互延续。结论:乙状结肠和左侧腰大肌筋膜之间的粘连带是左半结肠切除术外侧分离的起点。肾前筋膜是衬贴于左半结肠和直肠系膜后面的一层连续筋膜,在不同的解剖位置有不同的表现形式。左半结肠切除术的外科平面统一于结直肠系膜与连续的肾前筋膜之间。 相似文献
99.
Autoantibody response to the Ro/La particle may predict outcome in neonatal lupus erythematosus. 总被引:3,自引:0,他引:3
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E D Silverman J Buyon R M Laxer R Hamilton P Bini J L Chu K B Elkon 《Clinical and experimental immunology》1995,100(3):499-505
This study was undertaken to determine the role of antibodies against both recombinant Ro (r-Ro) and La (r-La) proteins and polypeptides derived from the recombinant La protein in predicting fetal and neonatal outcome in children at risk to develop neonatal lupus erythematosus (NLE). All sera were obtained in the perinatal period and quantitative ELISA assays were used. We collected 41 maternal sera within 2 months of delivery of a child with NLE (21 with congenital heart disease block (CHB) and 20 with dermatologic NLE) and 19 sera from anti-Ro and/or anti-La antibody-positive mothers with systemic lupus erythematosus (SLE) who delivered a child without NLE. All sera were tested for anti-r-La and anti-r-Ro antibodies by ELISA, and most sera were tested for antibodies directed against La polypeptides by immunoblot. We found significantly higher anti-r-La antibody levels in the sera from mothers of children with NLE compared with sera from mothers of unaffected children (0.67 +/- 0.43 versus 0.14 +/- 0.30; P < 0.0001). There was a statistically significant difference in the mean anti-r-La levels between the sera of mothers of children with CHB compared with dermatologic NLE (0.51 +/- 0.45 versus 0.83 +/- 0.37 respectively; P = 0.0091). When we examined antibodies directed against the recombinant 52-kD Ro protein, there was a statistically significant elevation of titres in the sera of mothers of NLE children (0.77 +/- 0.35) compared with non-NLE mothers (0.29 +/- 0.39; P < 0.0001). There was no difference in the r-Ro levels between mothers of children with dermatologic NLE compared with CHB (0.82 +/- 0.37 versus 0.71 +/- 0.74; P = 0.32). When we examined polypeptides derived from the recombinant La protein, the mean number of polypeptides recognized by sera from mothers of children with NLE was significantly higher than the mean number of polypeptides recognized by sera from mothers of unaffected children (5.1 +/- 0.54 versus 2.3 +/- 0.54 respectively; P < 0.001). More importantly, when we examined the individual polypeptides, we found that only sera from mothers of children with NLE and not from mothers of unaffected children recognized a polypeptide designated DD (30% versus 0%, respectively). These studies indicate that the autoantibody response to the Ro/La particle can differentiate sera from mothers of children with NLE and sera from mothers of unaffected children. Furthermore, there was a difference in the anti-La autoantibody response between mothers of children with CHB and dermatologic NLE.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
100.
网膜囊上隐窝的CT应用解剖 总被引:4,自引:1,他引:4
在42套腹部断面标本及50例整尸上观察到:网膜囊上隐窝呈“V”形间隙围绕肝尾状叶,前界为小网膜及肝左叶,后界是膈,顶由肝冠状韧带或膈形成,下抵胰,左邻食管;在正中矢状面上均出现肝尾状叶,且尾状叶套入或游离于网膜囊上隐窝。这些结果对在 CT 图像上鉴别尾状叶周围的积液及肿块具有重要意义。 相似文献