悬浮阵列技术在研究与临床中的应用

悬浮阵列技术是一种以荧光编码微球为核心,集流式细胞、激光分析、高速数字信号处理等多种技术于一体的多指标并行分析技术平台,可一次同时准确定量检测100种不同的生物分子;具有高通量、高灵敏度,并行检测等特点;常用于免疫分析、核酸研究、酶学分析、受体、配体识别分析等研究.     

人体β-胡萝卜素的肠转化和吸收后转化的研究

目的 :为了解部分中国人体内 β 胡萝卜素 ( β carotene ,以下简称 β C)转化维生素A (vitaminA ,以下简称VA)的效率 ,开展了本研究。方法 :使用稳定同位素稀释法对 15名 5 0 60岁健康农村志愿者 (男 9,女6)进行β C人体代谢实验。 2周适应期和 5 6天实验期内 ,志愿者接受常规膳食 ,避免大量VA和 β C摄入以及烟、酒和营养补充剂。实验第 1天 ,给受试者含 6mg氘标记 β C( 2 H8β C)玉米油胶丸 ,随半流质早餐 (脂肪热能比 2 5 % )一起摄入。实验第 4天 ,受试者以同样方法摄入含 3mg氘标记醋酸视黄醇 ( 2 H8RAC)油剂胶丸。实验第 1天和第 4天摄入标记物后 0 ,3 ,5 ,7,9,11,13h时 ,实验第 2 ,3 ,5 ,6,7,8,9,10 ,14,2 1,2 8,3 5 ,42 ,49,5 6天晨空腹时 ,采静脉血。用高效液相色谱仪 (HPLC)分离血清 β C和VA组分 ,再分别使用气相质谱仪(GC MS)和液相质谱仪 (LC MS)测定VA和 β C组分的同位素丰度。根据VA和 β C的浓度和同位素丰度 ,描述标记VA和β C在体内应答的血液动力学曲线。 结果 :所有 15名受试者对2 H8RAC应答明显 ;但是在对2 H8β C的应答方面 ,只有 11名受试者2 H4视黄醇应答曲线明显 ,有 4名受试者血清2 H4视黄醇应答曲线非常微弱。经过对备份血清样品进行的多次重复GC MS测定 ,我们目前初步?     

双波长法在芦丁和槲皮素2组份共存下芦丁含量的测定

研究了双波长技术在干扰物槲皮素存在下测定芦丁含量的方法,槲皮素浓度大到20mg/L时,误差不超过0.4％,回收率为94.2％～100.2％。     

Epidural block for obstetrics: Comparison of bolus injection of local anesthetic with gravity flow technique

Study Objective: To test the hypothesis that slow administration of local anesthetic into the epidural space by gravity flow reduces the incidence of signs and symptoms of unintended injection.

Design: Prospective, randomized study.

Setting: Teaching hospital.

Patients: 600 ASA physical status I and II parturients scheduled for labor and delivery or elective cesarean section.

Interventions: After identification of the epidural space with pulsations of an air-fluid column, parturients for vaginal delivery (n = 380) were randomized to receive a test dose of 3 ml 3% 2-chloroprocaine with epinephrine 20 μg, two doses of 7 ml bupivacaine 0.03 % with sufentanil 1 μg/ml and epinephrine 2 μg/ml by either gravity flow (Group 1) given over 30 seconds or by bolus injection (Group 2) given over 5 seconds through the epidural needle; parturients for Cesarean delivery (n = 220) were randomized to receive a test dose and two doses of 6 ml lidocaine 2 % with sufentanil 1 μg/ml and epinephrine 2 μg/ml by either gravity flow or by bolus injection through the epidural needle. Changes in maternal heart rate (HR) and blood pressure, signs of intravascular injection, and adverse effects of epidural bupivacaine-sufentanil were recorded after each dose.

Measurements and Main Results: Gravity flow administration (Group 1) was associated with a smaller increase in mean maternal HR (p < 0.001), less hypotension (p < 0.01), sedation (p < 0.01), nausea (p = 0.01), and segmental spread (p < 0.0001) than were corresponding doses given by traditional bolus injection (Group 1) for vaginal or Cesarean deliveries. The incidence of systemic toxicity was zero of 300 (0%) with gravity flow and 4 of 300 (1.3%) by bolus injection, p = 0.12, Fisher's exact test. No patient in either group had an accidental intrathecal injection.

Conclusion: Gravity flow administration of local anesthetic-opioid solution during epidural block for obstetrics was associated with fewer signs of systemic drug absorption and cardiovascular perturbations than was the traditional bolus injection. This study supports the current opinion that slow administration of local anesthetic during epidural black contributes to fewer adverse events.     

Allergic contact dermatitis from grasses

This study attempts to demonstrate the existence of allergic contact dermatitis from grass, and to develop a patch test series to screen patients with grass intolerance. 6 common grass species from lawns and military training areas were collected. Solvent extracts of polar. non-polar and volatile fractions were prepared and used for patch testing in 20 control subjects and 46 patients with a history of grass intolerance. The 20 control had negative responses to patch testing. 5 out of 46 patients had positive patch tests to Axonopus compressus (carpet grass). Ischaenmum muticum (sea-shore centipede grass). Imperata evlindrica (lalang). Panicum maximum (Guinea grass) and Pennisetum purpureum (elephant grass). Reactions to the non-polar fraction for all 5 species were noted. This study demonstrates the existence of allergic contact dermatitis from various common species of grass. In our series, this is seen in 11% of those with a history of grass intolerance.     

大鼠下丘脑弓状核的形态计量研究

为了探讨急性癫痫弓状核形态改变与可复性，我们采用光、电镜技术和形态计量方法对下丘脑弓状核进行了形态定量研究。结果显示：弓状核切面面积为317500±6460um2，神经元胞体和胞核的等效直径分别为12.94±0.34um和8.54±0.43um，暗细胞内线粒体、粗面内质网、高尔基复合体、溶酶体、游离核相体和分泌颗粒的面积分数分别是5.87±1.98％、3.53±0.25％、0.81±0.49％、2.13±0.42％、10.53±0.46％和0.86±0.35％，其面数密度（单位面积为30um2）分别为15.68±1.14um-2、21.29±3.52um-2、10.20±0.42um-2、5.62±067um-2、101.35±7.55um-2和5.22±0.77um-2.本文还对弓状核的形态结构、神经元类型及其功能进行了讨论。     

Comparison of Tympanic, Esophageal and Blood Temperatures during Mild Hypothermic Cardiopulmonary Bypass: A Study using an Infrared Emission Detection Tympanic Thermometer

Objective. Tympanic temperature can be obtained instantaneously using an infrared emission detection (IRED) thermometer. Its accuracy has been documented in a variety of clinical settings, but its performance at low body temperatures is still unknown. In this study we evaluated its performance during coronary artery revascularization surgery in which mild hypothermic cardiopulmonary bypass (CPB) was used. Methods. Thirty adult patients undergoing coronary artery bypass graft surgery were enrolled in the study. Tympanic temperature obtained using IRED thermometry (Tt1) was compared with core temperatures from the esophagus (Te), and venous blood of CPB (Tv) before, during, and after CPB. We also measured tympanic temperature using a thermocouple probe (Tt2) in 16 of the 30 patients in order to study the agreement between the two methods. Values for correlation coefficients and limits of agreement were computed to assess the degree of agreement among the temperatures obtained. Results. The highest agreement with Tv during CPB was obtained from Tt1 (r = 0.94, 0.41 ± 1.73, limits of agreement) and from Te (0.91, 0.36 ± 2.46). Tt1 also showed good agreement with Tt2 during surgery. Conclusions. Infrared tympanic thermometry is a reliable, alternative method to measure tympanic temperature and may be useful to assess core temperature in both normothermic and mild hypothermic conditions.     

Finishing techniques for amalgam restorations: Clinical assessment at three years

Use of the optimum finishing technique for an amalgam restoration may enhance the marginal integrity of the restoration and discourage its unnecessary early replacement. Two hundred and twenty-eight high copper amalgam restorations in 56 patients were evaluated, using clinical assessment criteria, up to three years after placement. Each patient had received at least one carved-only amalgam, at least one immediately finished restoration, and at least one amalgam that was polished at a subsequent appointment. Regardless of the finishing technique, the restorations exhibited similar marginal integrity up to three years after placement. Polished restorations were found to have substantially superior surface texture and less likelihood of surface discoloration. No evidence was found to support the use of immediate finishing techniques. The clinical significance of these findings, with respect to the need to polish amalgam restorations, is discussed.     

Demonstration of dilatation of peripheral airways

Summary. To investigate the ability of various lung-function tests to demonstrate dilatation of peripheral airways, ten asthmatics inhaled increasing doses of a f2-agonist by two different and controlled techniques. Low inspiratory flow with a long post-inspi-ratory pause favoured peripheral deposition, and a high inspiratory flow with a short post-inspiratory pause favoured central deposition of drug in the airways. Ordinary spirometry, maximum expiratory flow rates after breathing air as well as a helium-oxygen mixture, a single breath N₂-test and resistance of the respiratory system were obtained before and after each of five terbutaline doses with both inhalation techniques. By using a double-dummy technique, the study could be performed double blinded. Effects were compared at doses giving equal effects on PEF, assumed to represent equal deposition of bronchodilator and effects on central airways. At such ‘iso A PEF doses’, particularly FVC and the slope of phase III of the N₂-test improved more following the slow inhalation technique. It is concluded that changes in those tests reflect dilatation in peripheral airways in asthmatics.,     

Intubating conditions provided by propofol and alfentanil - acceptable, but not ideal

Background: The use of muscle relaxants to facilitate intubation is associated with several side effects regardless of whether depolarizing or non-depolarizing drugs are used. In the present study we compared the intubating conditions, haemodynamic responses and changes in oxygen saturation following induction with alfentanil and propofol or alfentanil, thiopental and suxamethonium.
Methods: Eighty patients (ASA I or II) were in a double-blind manner assigned to receive either of the two induction methods. Intubating conditions were assessed on the basis of jaw relaxation, ease of insertion of the endotracheal tube and coughing on intubation. Heart rate, systolic arterial pressure and oxygen saturation were monitored throughout the procedure.
Results: The use of alfentanil and propofol resulted in significantly lower scored intubation points. Systolic arterial pressure decreased and heart rate increased significantly in the alfentanil-thiopental-suxamethonium group as compared to the alfentanil-propofol group. There were no significant changes in oxygen saturation.
Conclusion: The results show that propofol and alfentanil in combination provides haemodynamic stability and unaltered oxygen saturation but less optimal intubating conditions.