川芎挥发油化学成分研究

采取闪蒸气相毛细管色谱法和气相毛细管色谱—质谱法研究了宁夏六盘山区产川芎的挥发油化学成分,色谱分离出50多个峰,质谱鉴定了24个成分,主要是川芎酜内酯(46.37％)、丁基酞内酯(13.87％)、新蛇床内酯(6.98％)和丁烯基酜酯(4.8％)。红外光谱图中有较强的内酯特征吸收峰,为质谱所鉴定的以上主要成分提供了佐证。将闪蒸气相色谱法与蒸气蒸馏提取气相色谱法进行对照,二者的色谱图基本相符,前者是分析天然产物挥发性成分更加简便、迅速的微量方法。     

气相色谱用于肠通透性监测的研究

作者采用国产气相色谱及９２０２微机数据处理系统，对临床患者和实验动物肠通透性改变进行监测。该方法以甘露醇（Ｍ）和乳果糖（Ｌ）为探针，用气相色谱检测尿中糖分泌率及Ｌ／Ｍ比值。结果显示，测定标准品Ｍ和Ｌ随进样量增加而呈线性改变，与国外学者报道一致。比较不同浓度进口与国产乳果糖，证明二者在研究肠通透性方面高度相关（ｒ＝０．９９）。检测急性胰腺炎并发感染动物的尿标本，发现乳果糖大量排出，Ｌ／Ｍ值明显增加。作者认为，气相色谱为一行之有效的方法用于肠通透性监测，有助于临床上对内源性感染及脓毒症的早期诊断。     

Diving physiology and pathophysiology

Summary. Divers have worked at 500 m depth in the sea and have reached 700 m in simulated chamber dives. A prerequisite for this has been extensive physiological studies of the body's reactions to pressure and pressure changes. This paper reviews such physiological and pathophysiological studies with emphasis on recent developments.     

气相色谱法测定异硝苯地平

采用气相色谱法，以尼莫地平为内标测定钙拮抗剂异硝苯地平。方法简便快速，结果准确可靠。回收率99.78％，相对标准偏差0.43％，符合定量测定的要求。     

Permissive Hypercapnia and Intravascular Oxygenator in the Treatment of Patients with ARDS

Abstract: This open clinical study was aimed at testing the hypothesis that an intravascular oxygenator (IVOX) may help to perform permissive hypoventilation in 10 patients with severe ARDS. After initial evaluation, we tried to reduce ventilator settings before and after IVOX implantation. Before IVOX, poor clinical tolerance and worsening oxygenation did not allow for a significant decrease in ventilator settings. With IVOX, peak inspiratory pressure (PIP) was reduced from 47 to 39 cm H₂O (p = 0. 005) and minute ventilation from 13 ± 3. 5 to 11 ± 3 L/min. CO₂ removal by IVOX allowed a significant decrease in Paco₂ from 66 ± 15 to 59 ± 13 mm Hg. Improvement of oxygenation with IVOX was not signify cant. Furthermore, interruption of oxygen flow through IVOX did not change oxygenation variables. Tolerance of the IVOX device was good, but insertion of the device was followed by a significant decrease in both cardiac index and pulmonary wedge pressure. In conclusion, IVOX improves tolerance of hypoventilation by limiting hypercapnia in ARDS patients. These preliminary results must be confirmed by a randomized controlled study     

52例肺癌患者放疗前肺功能和放疗疗效关系分析

为了探讨放疗前肺功能与放疗疗效的关系，作者于１９８７年１月至１９９０年１２月对５２例无急、慢性呼吸衰竭的肺癌患者在放疗前做了肺功能检测和血气分析，结果表明，放疗前肺功能不能反映肿瘤乏氧程度，也不能作为肿瘤对放疗敏感性的指标，只有直接测量肿瘤原发灶内的乏氧程度才能了解肿瘤对放疗的敏感性，预测放疗的疗效。     

Pathophysiological aspects of predominant preload lowering on pulmonary circulation, gas exchange, and the biventricular function in patients with chronic obstructive lung disease

A group of 21 patients with various degrees of chronic obstructive pulmonary disease underwent radionuclide ventriculography with hemodynamic monitoring to assess the extent to which pulmonary artery pressures and pulmonary vascular resistance can be lowered by the vasodilator molsidomine. Molsidomine (N-carboxy-3-morpholino-sydnonimin-ethylester) is similar to nitroglycerin in its mode of action. After hemodynamic and radionuclide data acquisition, at rest and during submaximal exercise in the steady state, 2 mg molsidomine was injected intravenously. Rest and exercise measurements were repeated 45 min after molsidomine injection. In patients with mild to moderate disease (group 1), pulmonary artery resting pressures decreased by 12% (p less than 0.05) at rest by 22% (p less than 0.01) during exercise after the administration of the drug. Total pulmonary resistance during exercise decreased significantly (p less than 0.01) as a result of marked decrease of pulmonary artery pressure (PAP) compared with a minimal decrease in cardiac index (CI). In patients with severe disease (group 2), only the resting values of PAP decreased while the relationship between pressure and flow was unchanged. During the exercise period, the preload parameters of the right and left ventricles decreased by an average of 30%. With regard to gas exchange, only the arterial PO2 at rest decreased slightly but significantly (p less than 0.05) after molsidomine, while the coefficient of oxygen delivery was not affected by the drug. However, in four patients arterial PO2 was markedly reduced by the drug. Right ventricular ejection fraction increased significantly (p less than 0.01) both at rest and during exercise in group 1 and during exercise in group 2 after administration of molsidomine.(ABSTRACT TRUNCATED AT 250 WORDS)     

烧伤家兔血液流变学变化与血气分析的观察

在家兔左腿背侧部与腹部以100℃电烙铁造成10％面积2度烧伤,腹部烧伤占1/2。烧伤后血压持续下降。血浆比粘度在2h内持续增加,全血比粘度在1h内呈现增高,2h后为下降。pH与paCO_2烧伤后下降。PaO_2先下降后升高,这升高现象不同于临床所见。BE_5 1h后负值增大。实验动物在烧伤后3～4h死亡。     

Use of long catheters for multipatient anesthetic monitoring at high respiratory frequencies

Anesthetic gases from several patients can be monitored simultaneously with a centrally located mass spectrometer. Such monitoring requires catheters from patient to spectrometer that are several meters long. Scamman (J Clin Monit 1988;4:227–229) found that when the respiratory frequency is high, as with infants, the CO₂ signal from the patient is unacceptably distorted during passage down the catheter. This is due to Taylor dispersion of the input signal. An outline of the theory of Taylor dispersion is given. The equations describe the interaction between the velocity distribution (which, in laminar flow, is parabolic) and the radial diffusion of CO₂. This interaction keeps a tracer signal together in a pulse, as it moves down the tube with themean velocity, spreading somewhat as it proceeds. How much does an initially sharp signal become blurred? The spread of such a signal when it reaches the detector, measured in time, can be expressed in various ways. Measurement is complicated, however, by the fact that the gas pressure may fall by as much as a factor of 10 along the line. The resultant expansion and acceleration of the gas cannot be ignored. A full treatment of this complication is given elsewhere, but the following simple equation is described: {ie237-1} Typically, the spread time is up to a quarter of a second for catheters of 50 m, such as used by Scamman. This is comparable with the period of CO₂ rise and fall for infants and explains the serious distortion in wave form that Scamman found. Some distortion can be eliminated by reducing R to 0.1 or less, but the extent of this improvement is small. Ideally, for fast-breathing patients, the catheter length should be reduced to 20 m or less, if possible.