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31.
The purpose of this study was to investigate the atrioventricular AV nodal physiology and the inducibility of AV nodal reentrant tachycardia (AVNRT) under pharmacological autonomic blockade (AB). Seventeen consecutive patients (6 men and 11 women, mean age 39 ± 17 years) with clinical recurrent slow-fast AVNRT received electrophysiological study before and after pharmacological AB with atropine (0.04 mg/kg) and propranolol (0.2 mg/kg). In baseline, all 17 patients could be induced with AVNRT, 5 were isoproterenol-dependent. After pharmacological AB, 12 (71 %) of 17 patients still demonstrated AV nodal duality. AVNRT became noninducible in 7 of 12 nonisoproterenol dependent patients and remained noninducible in all 5 isoproterenol dependent patients. The sinus cycle length (801 ± 105 ms vs 630 ± 80 ms, P < 0.005) and AV blocking cycle length (365 ± 64 ms vs 338 ± 61 ms, P < 0.005) became shorter after AB. The antegrade effective refractory period and functional refractory period of the fast pathway (369 ± 67 ms vs 305 ± 73 ms, P < 0.005; 408 ± 56 ms vs 350 ± 62 ms, P < 0.005) and the slow pathway (271 ± 30 ms vs 258 ± 27 ms, P < 0.01; 344 ± 60 ms vs 295 ± 50 ms, P < 0.005) likewise became significantly shortened. However, the ventriculoatrial blocking cycle length (349 ± 94 ms vs 326 ± 89 ms, NS) and effective refractory period of retrograde fast pathway (228 ± 38 ms vs 240 ± 80 ms, NS) remained unchanged after autonomic blockade. Pharmacological AB unveiling the intrinsic AV nodal physiology could result in the masking of AV nodal duality and the decreased inducibility of clinical AVNRT.  相似文献   
32.
妇科腹腔镜手术中转开腹原因分析   总被引:2,自引:1,他引:1  
邓国义  林虹 《中国内镜杂志》2007,13(12):1321-1322
目的探讨妇科腹腔镜手术中转开腹的原因。方法对1234例妇科腹腔镜手术中的中转开腹患者的病情进行总结分析。结果16例腹腔镜中转开腹患者中,盆腔严重粘连者7例,盆腔恶性肿瘤4例,其他5例。结论盆腔严重粘连和盆腔恶性肿瘤是妇科腹腔镜手术中转开腹的主要原因,术前、术中充分的病情评估可能有助于减少中转开腹的发生。  相似文献   
33.
目的 研究虹膜夹型有晶状体眼人工晶状体(iris-claw phakic intraocular lens,ICPIOL)植人术后对比敏感度(contrastsensitivity,CS)的变化。方法 2005年5月至12月于温州医学院附属眼视光医院和中山大学中山眼科中心接受ICPIOL(Verisyse,美国AMO公司)植入术的高度近视眼患者12例(23只眼),分别在术前、术后1、3、6个月采用CS测试灯箱(CSV-1000型,美国Vector Vision公司)检查暗视状态下无/有眩光时的对比敏感度函数(contrast sensitivity function,CSF)。结果 术后1、3、6个月等效球镜度数分别为(-0.60±0.77)D,(-0.48±0.77)D,(-0.34±0.53)D,与术前(-15.53D±3.65D)差异均有显著统计学意义(P均〈0.001),最佳矫正视力(IogMAR)分别为0.064-0.12,0.02±0.09,-0.003±0.08,与术前(0.21±0.12)差异均有显著统计学意义(P均〈0.001)。术后各空间频率的CS与术前比较有增高趋势。术后3个月6、12、18周/度的CS在无眩光时和有眩光时均明显提高(P均〈0.01),开始接近正常范围。术后3、6个月在各空间频率上CS差异均无统计学意义(P均〉0.05)。结论 ICPIOL植入术矫治高度近视眼可以使CSF恢复到接近正常范围,显著改善视功能,是一种适用于高度乃至超高度近视眼的可供选择的屈光手术。  相似文献   
34.
To characterize the 68 kDa allergen of Penicillium notatum (also known as P. chrysogenum), a molecular antibody (MoAb) (P40) was previously generated. For cDNA cloning, three more MoAbs (3F, 5A3, 5G2) were generated in the present study. A mixture of all the four MoAbs was used in cloning of the gene coding for the 68 kDa allergen from a λgt11 cDNA library of P. chrysogenum. A cDNA clone (A6) with DNA insert of about 0.5 kb which encodes for the 3′-terminal nucleotide sequence of the 68 kDa allergen was obtained. The cloned sequence contained two putative N-glycosylation sites. The reduction in molecular weight from 68 to 62 kDa in immunoblotting after treatment of the crude extract of P. notatum with N-glycosidase F indicates that the 68 kDa allergen is a glycoprotein. Nucleotide sequence determination showed that 188 (54%) of the 348 nucleotides of the cDNA sequence obtained were identical to the same region of the nucleotide sequence of the beta-N-acetylglucosaminidase gene of Candida albicans. Although the cDNA clone obtained did not encode the full-length gene of the 68 kDa allergen, polypeptide expressed from the A6 cDNA showed positive immunological reactivities to all four MoAbs used in the cloning experiment and to IgE antibodies in sera of asthmatic patients. There was a loss of immunoblotting activity to the 68 kDa component after absorption of MoAb P40-containing culture supernatant with filters blotted on plaque lawns of cDNA clone A6. Moreover, the immunoblotting activity remained when the MoAbs affinity-purified with filters containing polypeptides encoded by the cDNA insert of clone A6 were used. These two observations indicate that clone A6, which encodes 117 amino acid residues of a putative 560-residue polypeptide, is a cDNA clone of the 68 kDa component of P. notatum. In conclusion, results obtained from cloning and characterization of a partial cDNA clone described in this study suggest that the 68 kDa allergen of P. notatum is a beta-N-acetylglucosaminidase.  相似文献   
35.
Abstract Somatostatin has been used to effectively control acute variceal haemorrhage, with conjectured mechanisms on portal hypertension. We, therefore, evaluated the effects of somatostatin on hepatic and systemic haemodynamics in 15 patients with hepatitis B-related cirrhosis and portal hypertension. All patients received an intravenous, continuous infusion of somatostatin 250 μg/h, following a bolus injection of 250 μg. In systemic haemodynamics, the mean arterial pressure (MAP) increased ( P < 0.05), associated with a reflex bradycardia within 3 min following bolus injections, compared with basal values. The right atrial pressure, pulmonary capillary wedge pressure, inferior vena cava pressure, cardiac index, and systemic vascular resistance remained unaffected after drug infusion. In hepatic haemodynamics, the wedge hepatic vein pressure remained unchanged after drug administration. However, there was an increase in free hepatic vein pressure (FHVP; P < 0.05), and a trend toward a decrease in the hepatic vein pressure gradient (HVPG; P = 0.063), within 3 min after bolus injection. Furthermore, the hepatic blood flow decreased significantly at 10 and 30 min after somatostatin infusion ( P < 0.05). The effective sinusoidal perfusion assessed by indocyanine green infusion also decreased progressively at 10 min ( P = 0.057) and 30 min ( P < 0.05). We concluded that somatostatin, at the dose used in this study, caused a transient and bolus-related vasoconstrictive effect, resulting in increases in MAP and FHVP, a decrease in heart rate, and a trend toward lower HVPG. In addition, somatostatin reduced the hepatic blood flow and effective sinusoidal perfusion which may be hazardous to cirrhotic patients during variceal haemorrhage.  相似文献   
36.
Abstract— The γ-pyrones, artomunoxanthotrione epoxide, cyclocommunol, cyclomulberrin, and cyclocommunin exhibited potent inhibition of human PLC/PRF/5 and KB cells in-vitro. Dihydroisocycloartomunin showed significant and potent inhibition of human PLC/PRF/5 and KB cells in-vitro, respectively. Cyclomorusin, dihydrocycloartomunin and artomunoxanthone showed significant inhibition of KB cells in-vitro. Based on the above finding and the reported antileukaemic activity of xanthone psorospermin, a series of natural γ-pyrones was prepared and the inhibition of human PLC/PRF/5 and KB cells in-vitro was measured. Structure-activity analysis indicated the epoxide group substituted at 3-hydroxyl and 2,6-; 3,6-; and 3,5-dihydroxyl xanthone enhanced the anti-tumour activity. The epoxide group substituted at the 6-hydroxyl group of 1,6-dihydroxyxanthone did not show anti-tumour activity.  相似文献   
37.
环孢素A体外诱导HL—60细胞凋亡的研究   总被引:3,自引:1,他引:3  
目的:观察环孢素A是否有诱导白血病细胞凋亡的作用。方法:应用细胞形态学检查、二苯胺法DNA片段化定量,DNA凝胶电泳及流式细胞术等方法观察细胞凋亡。结果:CsA50mg/L作用HL-60细胞4h,DNA片段率显著增高,达(28.2±5.8)%,而对照组仅为(12.5±1.7)%(P<0.01,n=10)。光镜及电镜检查见细胞核固缩,碎裂,有凋亡小体形成。DNA电泳显示典型的DNAladder。流式细胞术检测发现CsA50mg/L作用HL-60细胞6h凋亡细胞率为49.7%,而空白组仅为9.1%。CsA诱导HL-60细胞DNA片段化呈剂量和时间依赖性。结论:CsA在体外能诱导HL-60细胞凋亡。  相似文献   
38.
39.
目的 了解脐带血T细胞及其CD4 和CD8 T细胞亚群的信号传导分子CD3ζ基因的表达特点.方法 采用SYBR Green Ⅰ荧光定量PCR和相对定量分析法检测60例脐带血单个核细胞和12例纯化脐带血CD4 及CD8 T细胞的CD3ζ基因的表达情况,以β2微球蛋白基因(β2M)作为内参,采用相对定量公式:2-△Ct×100%,计算CD3ζ基因相对mRNA表达量,60例健康成人作为对照.并根据荧光定量PCR熔解曲线特点和序列分析了解CD3ζ基因突变情况.结果 全部脐带血和健康成人外周血单个核细胞均表达CD3ζ基因,不同个体CD3ζ基因表达量有所差异,脐带血T细胞CD3ζ基因相对mRNA表达量为6.7%±5.56%,CD4 和CD8 T细胞的CD3ζ基因相对mRNA表达量分别为6.74%±2.0%和6.88%±1.76%,三者CD3ζ基因表达量均明显高于健康成人(P=0.000,P=0.034,P=0.000).序列分析结果显示尚未发现国外文献所报道的ζ链剪接异构体.结论 本研究率先报道了脐带血T细胞及其CD4 和CD8 T细胞亚群的CD3ζ基因mRNA的表达水平,为进一步了解脐带血T细胞免疫学特点提供新的基础资料.  相似文献   
40.
目的 研究人外周血CD4^ /CD8^ T细胞4种神经营养素受体基因的转录。方法 应用尼龙手法分离出T细胞,磁式细胞分离法(MACS)分离CD4^ /CD8^ T细胞亚群,再以RT-PCR法研究4种神经营养素受体在两种T细胞亚群上的表达。结果 未经刺激的CD4^ /CD8^ T细胞亚群不表达任何神经营养素受体。经PHA或PPD刺激后,CD4^ /CD8^ T细胞亚群表达trkA,CD8^ T细胞亚群表达trkC;而在各种状态下的T细胞上均未见表达trkB及p75^NGFR。结论神经营养素受体在两种T细胞亚群中有不同的表达格局,提示不同T细胞亚群受神经营养素调节的模式可能各不相同。  相似文献   
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