依达拉奉防治缺血性脑损伤研究的新进展

近年来,依达拉奉脑保护作用的研究取得了很大进展,尤以对缺血性脑卒中和新生儿缺血缺氧性脑病的防治研究最为深入,而联合治疗策略也得到了广泛的重视.本文就近5年这些热点研究的新进展进行综述.     

Whole-heart cine MRI using real-time respiratory self-gating.

Two-dimensional (2D) breath-hold cine MRI is used to assess cardiac anatomy and function. However, this technique requires cooperation from the patient, and in some cases the scan planning is complicated. Isotropic nonangulated three-dimensional (3D) cardiac MR can overcome some of these problems because it requires minimal planning and can be reformatted in any plane. However, current methods, even those that use undersampling techniques, involve breath-holding for periods that are too long for many patients. Free-breathing respiratory gating sequences represent a possible solution for realizing 3D cine imaging. A real-time respiratory self-gating technique for whole-heart cine MRI is presented. The technique enables assessment of cardiac anatomy and function with minimum planning or patient cooperation. Nonangulated isotropic 3D data were acquired from five healthy volunteers and then reformatted into 2D clinical views. The respiratory self-gating technique is shown to improve image quality in free-breathing scanning. In addition, ventricular volumetric data obtained using the 3D approach were comparable to those acquired with the conventional multislice 2D approach.     

经闭孔无张力尿道中段悬吊术治疗女性压力性尿失禁

目的探讨经闭孔无张力尿道中段悬吊术(trans-obturator tension free vaginal tape,TVT-O)治疗女性压力性尿失禁(stress urinary incontinence,SUI)的临床疗效。方法2006年1月~2007年9月,对15例SUI行TVT-O,取阴道前壁纵行切口1cm,组织剪分离尿道旁阴道黏膜下间隙至闭孔膜,放入蝶形导引杆,将螺旋形穿刺针沿导引杆紧贴耻骨下支穿过闭孔膜,从大腿根部皮肤穿出,将吊带无张力放置于尿道中段下方。结果手术时间15~40min,平均30min。术中出血量10~40ml,平均20ml。术中无并发症。1例术后尿潴留,留置尿管5d后缓解。10例术后大腿根部疼痛,术后3~10d消失。15例随访2~19个月,平均8个月,均治愈,无复发。结论TVT-O操作简单、安全有效。     

The significance of involvement of a free serosal surface for recurrence and survival following resection of clinicopathological stage B and C rectal cancer

OBJECTIVE: To determine whether the presence of tumour at a free serosal surface was independently associated with pelvic recurrence or survival in patients who had a resection for clinicopathological stage B or stage C rectal cancer and who had not received adjuvant therapy. METHOD: Data were drawn from a comprehensive, prospective hospital registry of all resections for rectal cancer from January 1971 to December 1998 with follow up to December 2003. Statistical analysis employed the chi(2) test or Fisher's exact probability, Kaplan-Meier estimation and proportional hazards regression, with a significance level of < or =0.05 and 95% confidence intervals (CI). RESULTS: In 665 patients with stages B or C tumour, 35 (5.3%; CI 3.7-7.2%) had tumour at a free serosal surface. These comprised 6/332 (1.8%; CI 0.8-3.7%) patients with stage B tumour and 29/333 (8.7%; CI 6.1-12.2%) with stage C tumour. After adjustment for other relevant variables, involvement of a free serosal surface was significantly associated with pelvic recurrence [hazard ratio (HR) 2.7; CI 1.3-5.5] and diminished survival (HR 1.6; CI 1.1-2.4) but not with systemic (only) recurrence. CONCLUSION: This study has confirmed that direct tumour spread to a free serosal surface independently predicts pelvic recurrence and diminished survival after resection of clinicopathological stage B and C rectal cancer. This feature should always be sought by the pathologist and reported when present, and noted by the surgeon and oncologist. Serosal involvement should be evaluated further for its utility in selecting patients for adjuvant therapy.     

老年腹股沟疝无张力修补术与传统修补术的比较

目的 比较无张力腹股沟疝修补术与传统腹股沟疝修补术在老年患者中应用的临床结果、术后生活质量和经济开支。方法 自2000～2001年60岁以上的老年患者42例行腹股沟疝无张力修补术与42例行传统腹股沟疝修补术者，分类比较。结果　无张力腹股沟疝修补术对于老年患者在复发率、术后镇痛、手术时间和术后下地时间方面均明显优于传统腹股沟疝修补术。结论　无张力腹股沟疝修补术运用在老年患者中，近远期效果均优于传统修补手术。     

靶向寡肽溶栓剂

对靶向寡肽溶栓剂P6A(ARPAK)及其衍生物、RGD肽及含有自由基伪肽的靶向溶栓作用进行综述。P6A是纤溶酶原的降解产物之一,具有增加血管通透性和溶栓作用。P6A的衍生物及P6A代谢产物具有更强的溶栓作用。血栓形成中,RGD序列是纤维蛋白原与血小板结合的关键序列。将RGD序列与溶栓寡肽结合,构成了具有靶向溶栓作用的杂交寡肽。在溶栓治疗中,血流再灌注生成的大量自由基会对组织造成损伤,将自由基清除剂与溶栓寡肽结合可得到具有溶栓和自由基清除双向功能的溶栓伪肽。因为溶栓处是产生大量自由基的部位,所以含自由基清除剂的溶栓伪肽可将自由基清除剂带到自由基堆积部位,体现了靶向内涵。     

氨乙基异硫脲对大鼠离体心脏冠脉结扎后再灌期心律失常与细胞动作电位的作用

用Langendorff方法与微电极技术研究自由基清除剂氨乙基异硫脲(AET)对离体大鼠心脏冠脉结扎后再灌期心律失常与细胞动作电位的作用。AET(0.001～1mmol/L)使室颤和室速发生率明显下降,使正常窦性心律时间增加。浓度为0.01～1mmol/L的AET可使不可逆室颤发生率下降为零。冠脉阻塞再灌损伤使缺血中心区心肌动作电位波形异常,APA,RP,V_(max)各参数下降。AET(0.1mmol/L)可使异常波形动作电位显著减少。     

Chemical Pathways of Peptide Degradation. V. Ascorbic Acid Promotes Rather than Inhibits the Oxidation of Methionine to Methionine Sulfoxide in Small Model Peptides

The effect of primary structure and external conditions on the oxidation of methionine to methionine sulfoxide by the ascorbate/Fe³⁺ system was studied in small model peptides. Degradation kinetics and yield of sulfoxide formation were dependent on the concentration of ascorbate and H⁺, with a maximum rate observed at pH 6–7. Phosphate buffer significantly accelerated the peptide degradation compared to Tris, HEPES, and MOPS buffers; however, the formation of sulfoxide was low. The oxidation could not be inhibited by the addition of EDTA. Other side products besides sulfoxide were observed, indicating the existence of various other pathways. The influence of methionine location at the C terminus, at the N terminus, and in the middle of the sequence was investigated. The presence of histidine in the sequence markedly increased the degradation rate as well as the sulfoxide production. The histidine catalysis of methionine oxidation occurred intramolecularly with a maximum enhancement of the oxidation rate and sulfoxide production when one residue was placed between the histidine and the methionine residue.     

电针对大鼠脑局部缺血-再灌流损伤的保护作用

再灌流前电针“环跳”穴３０ｍｉｎ，观察对左大脑中动脉（ＭＣＡ）缺血 再灌流模型大鼠早期运动功能、自由基代谢、脑水肿及神经电生理活动的影响。结果：缺血再灌＋针刺组大鼠再灌流后神经功能缺损状况有较明显的改善，病灶侧脑组织过氧化物歧化酶（ＳＯＤ）活性及丙二醛（ＭＤＡ）含量恢复到接近假手术对照组的水平。皮层体感诱发电位（ＳＥＰ）测量表明缺血侧Ｐ１潜伏期及Ｐ１ Ｎ１波幅亦有显著性改善。结果表明：于再灌流前电针处理对本模型脑缺血 再灌流损伤有保护作用     

Benzoyl Peroxide Solubility and Stability in Hydric Solvents

Saturated solubility and reaction rate constants for the decomposition of benzoyl peroxide in solution and suspension were determined for use in formulation development. The solvents studied included ethanol, propylene glycol, and cosolvent mixtures of PEG 400 and water. The solubility of benzoyl peroxide was inversely related to the solvent polarity, with greater solubility occurring with semipolar solvents. The stability of benzoyl peroxide in solution was dependent on the solvent, concentration of benzoyl peroxide, and temperature. The compound was least stable in PEG 400. Stability was improved when water was added to PEG 400. Similar solvent effects were observed in suspension. In benzoyl peroxide suspensions of PEG 400 and PEG 400/water blends, benzoyl peroxide stability was dependent on solubility, with improved stability occurring in blends where the benzoyl peroxide was least soluble. Thus, solution formulations of benzoyl peroxide in pharmaceutically acceptable solvents are unlikely to show good stability; however, suspension formulations should be reasonably stable if the vehicle is selected to provide low benzoyl peroxide solubility.