血清-腹水白蛋白梯度与食管静脉曲张关系的临床研究

探讨血清-腹水白蛋白梯度(SAAG)及测量门静脉直径在门脉高压性食管静脉曲张破裂出血预测中的价值。62例肝硬化腹水患者,其SAAG均≥11g/L符合门脉高压性腹水。其中并发食管静脉曲张破裂出血22例,非出血者40例,肝硬化并发食管静脉曲张破裂出血组之SAAG(21.34g/L±2.46g/L)及门静脉内径(1.43cm±0.12cm)均高于非出血组(15.57g/L±1.7g/L,1.08cm±0.14cm)差异均有统计学意义。因此认为血清-腹水白蛋白梯度及门静脉内径对预测门脉高压性食管静脉破裂出血有重要的临床价值。     

A new method of evaluating the degree of stenosis using a multisensor catheter

Summary A new method of evaluating the degree of stenosis using the pressure loss coefficient is presented here. The pressure loss coefficient was obtained in patients with pulmonary or aortic stenosis by measuring the pressure and velocity of the blood simultaneously with a multisensor catheter. Although the pressure gradient across the stenosis was augmented by increasing the blood velocity with pharmacological loading, the pressure loss coefficient remained nearly constant. This confirmed that the pressure loss coefficient is more appropriate for evaluating the degree of stenosis than the pressure gradient, which depends on the blood velocity.The pressure loss coefficients obtained from the preoperative and postoperative catheterization data were compared to evaluate the effects of the surgical operation. A pressure loss coefficient of 15 was proposed as the critical value for the indication of operation.     

Determination of the mean pressure gradient in mitral stenosis by Doppler echocardiography

Measurement of the mean pressure gradient provides an importantestimation of the severity of mitral stenosis. However, determinationof the mean pressure gradient from Doppler recordings has beenunsatisfactory using previously described methods. In this study,a new method for calculating the mean pressure gradient, theintegral method is described. It was developed from mathematicalanalysis of Doppler velocity curves. Doppler echocardiographyand cardiac catheterisation were performed in 23 patients withmitral stenosis to evaluate the accuracy of three current mathematicalmethods of determining the mean pressure gradient. The meanpressure gradients calculated by the three methods correlatedhighly with that measured by catheterisation (r=0.93). However,the mean pressure gradients calculated by the previously describedmean velocity square method and the arithmetical average methodunderestimated significantly that measured by cardiac catheterisation.In contrast, there was no significant difference between themean pressure gradients calculated by the integral method andmeasured by cardiac catheterisation. These results confirm theusefulness of Doppler echocardiography for determining the meanpressure gradient in mitral stenosis and demonstrate that amongcurrent methods, the integral method provides the most accuratecalculations of the mean pressure gradient.     

Genotoxic and cytotoxic effects of 4-aroyl-1-nitrosohydrazine-carboxamides onO 6-alkylguanine-DNA alkyltransferase-positive and-negative human cell lines

Five different representatives (I–V) of a new class of bifunctional alkylating agents, the 4-aroyl-1-nitrosohydrazinecarboxamides (nitrososemicarbazides), were evaluated for their potential interaction with DNA and for their cytotoxic activity in vitro toO ⁶-alkylguanine-DNA alkyltransferase-positive (Mer⁺) and-negative (Mer^–) human cell lines. The HeLa MR cell line (Mer^–) showed up to 20-fold higher sensitivity at IC₅₀ (dose that inhibits colony formation by 50%) to agents I–V than did the HeLa S3 cell line (Mer⁺) in a colony-formation assay. These data were compared to those obtained by treatment of the two cell lines with carmustine, a currently used antitumor drug. In Mer⁺ cells comparable results to those with carmustine were obtained with compounds III, IV and V; in Mer^– cells compounds I and II showed nearly the same effects as carmustine. Whether compounds I–V produce DNA strand breaks and/or DNA-protein cross-links was investigated using an alkaline filter elution technique. In this assay all compounds produced DNA single-strand breaks; no correlation could be detected between the strand breakage frequency and cytostatic, mutagenic and antitumor activity.Abbreviations Carmustine 1,2-bis-(2-chloroethyl)-1-nitrosourea - lomustine 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea - IC₅₀ dose that inhibits colony formation by 50% - PC polycarbonate - HVLP polyvinylidene fluoride     

Transmural atrial pacing in patients with postoperative congenital heart disease

INTRODUCTION: Some patients with postoperative congenital heart disease require permanent cardiac pacing, but the use of transvenous or epicardial pacing leads may be limited by type of cardiac malformation, venous connections, body size, or fibrosis. Transmural atrial pacing may provide an alternative in difficult patients, but to date has been described in only a few articles with small patient numbers, and data from lead performance are lacking. METHODS AND RESULTS: Records were reviewed in 18 consecutive patients (4 months to 21 years old) with postoperative congenital heart disease receiving transmural atrial pacing leads from July 1994 to December 1996. Implantation materials and techniques were described. Lead sensing and capture thresholds obtained acutely and during short-term follow-up (mean: 11.0 months) were evaluated, and comparisons were made between patients with postoperative Fontan anatomy and non-Fontan patients, and between patients receiving steroid-eluting and nonsteroid leads. Overall, the median acute sensing and capture thresholds of transmural leads were 4.1 m V and 0.7 V at 0.5 msec, respectively. Median follow-up thresholds were 2.8 m V and 0.8 V, respectively. Performance of leads in Fontan patients was similar to those in non-Fontan patients. Steroid-eluting leads had a chronic capture threshold of 0.6 V versus 0.9 V for nonsteroid leads (P = 0.038). CONCLUSION: Transmural atrial pacing leads were successfully implanted in patients with diverse ages and types of postoperative congenital heart disease. Lead performance was acceptable both acutely and during the first year of follow-up.     

Intervention Versus Observation in Symptomatic Patients With Normal Flow Low Gradient Severe Aortic Stenosis

Objectives

The purpose of this study was to describe patients with severe symptomatic aortic stenosis with normal flow and low gradients and determine whether they benefit from intervention.

Pulmonary Artery Denervation Significantly Increases 6-Min Walk Distance for Patients With Combined Pre- and Post-Capillary Pulmonary Hypertension Associated With Left Heart Failure: The PADN-5 Study

Objectives

The authors sought to assess the benefits of pulmonary artery denervation (PADN) among combined pre- and post-capillary pulmonary hypertension (CpcPH) patients in a prospective, randomized, sham-controlled trial.

First-Phase Ejection Fraction Is a Powerful Predictor of Adverse Events in Asymptomatic Patients With Aortic Stenosis and Preserved Total Ejection Fraction

Objectives

This study investigated the prognostic value of first-phase ejection fraction (EF1) in patients with aortic stenosis (AS), a condition in which left ventricular dysfunction as measured by conventional indices is an indication for valve replacement.

五种抗真菌药物对马尔尼菲青霉菌的体外抗菌活性观察

目的 了解两性霉素B(AMB)、酮康唑(KET)、氟康唑(FCA)、5-氟胞嘧啶(5-Fc)和伊曲康唑(ICA)5种抗真菌药物对马尔尼菲青霉菌体外抗菌活性,为临床用药提供参考依据.方法 采用浓度梯度法(E-test)测试AMB、KET、FCA、5-Fc、ICA 5种抗真菌药物对52株从不同AIDS患者骨髓、血液、皮肤损害标本中分离的马尔尼菲青霉菌酵母相和菌丝相的体外抗菌活性.数据采用U检验.结暴 AMB、KET、FCA、5-Fc、ICA的90%酵母相马尔尼菲青霉菌的最低抑制浓度(MIC90)分别为0.250、0.160、24.000、4.000和0.006 mg/L,最低抑制浓度(MIC)范围分别为0.004～0.500、00002～0.016、1.000～256.000、0.002～32.000和0.002～0.008 mg/L;对90%菌丝相马尔尼菲青霉菌的MIC90分别为1.500、0.125、256.000、24.000和0.012 mg/L,MIC范围分别为0.064～4.000、0.006～0.940、1.000～256.000、0.125～32.000和0.002～0.064 mg/L.不同抗真菌药对双相马尔尼菲青霉菌的体外抗菌活性不同,以ICA最强,其次为KET.酵母相和菌丝相的马尔尼菲青霉菌对同一药物的MIC比较差异有统计学意义(AMB、KET、FCA、5-Fc和ICA的U值分别为4.221 9、1.912、28.798、6.43、7.21,均P＜0.05).结论 进行马尔尼菲青霉菌体外抗真菌药物敏感实验对临床有重要参考意义.