流行性出血热人群传播速度的定量研究

选取家鼠型ＥＨＦ中发病区人群血清ＥＨＦ抗体阳性率资料，试用可逆催化模型对ＥＨＦ人群传播速度进行定量研究。结果表明：所建立的可逆催化模型其理论值与实际值理论拟合较好，用χ＾２做配合适度检验，Ｐ〉０．０５。证实可逆催化模型可用来作ＥＨＦ人群中传播速度的定量研究。还发现在家鼠型ＥＨＦ疫区每１０００人中约有８０人因有效接触而获得感染，同时又有４０人血清ＥＨＦ抗体转阴。     

Skeletal Status in Children,Adolescents and Young Adults with End-Stage Renal Failure Treated with Hemo- or Peritoneal Dialysis

The skeletal status in 30 children, adolescents and young adults (18 females, 12 males) with end-stage renal failure (ESRF) aged 9-23 years (mean 15.8 ± 3.6 years) was evaluated using measurements of bone mineral density (BMD, g/cm²) at the spine and total body (TB) (Lunar DPX-L, USA), quantitative ultrasound (QUS) of the hand phalanges (DBM Sonic 1200, IGEA, Italy) and laboratory investigations (parathyroid hormone, serum total and ionized calcium, serum phosphate). Eleven subjects were treated with hemodialysis and 19 with peritoneal dialysis. The mean value of the amplitude-dependent speed of sound (Ad-SoS, m/s) measured by QUS was significantly decreased in comparison with the value obtained in a group of 686 age-matched controls (1942 ± 74 m/s vs 2050 ± 77 m/s, p<0.0001). BMD measurements were also decreased in comparison with mean values for the healthy population (Z-scores for spine −1.47, and for TB −1.53). Duration of dialysis correlated significantly with spine-BMD, TB-BMD and Ad-SoS (r=−0.37, r = −0.45, r=−0.55, respectively, p<0.05), while duration of ESRF did not have such an influence. Laboratory investigations did not correlate with skeletal parameters. Ad-SoS correlated significantly with spine-BMD (r= 0.45, p<0.05) and TB-BMD (r= 0.56, p<0.01). Both QUS and BMD values correlated significantly with Tanner stages (r ranged from 0.59 to 0.69, p<0.001) and did not increase with age except for correlation between age and TB-BMD. In conclusion, skeletal status in the population studied is strongly affected by ESRF. Both QUS and BMD measurements show an ability to express skeletal changes in a similar manner, though the QUS parameter seems to be more sensitive at revealing changes due to renal failure. Received: 12 July 2001 / Accepted: 8 November 2001     

高效液相法测定金樱子中三萜酸类成分的含量

定量测定不同产地金樱子中2α,3α,19α,23-四羟基乌苏-12-烯-28-羧酸的含量.采用高效液相法,色谱柱:Kromasil-C18(4.6 mm×250 mm,5 μm)柱,大连依利特公司;检测波长203 nm,柱温:35 ℃;流动相:乙腈-水(35:65),流速1 mL/min.结果表示所测成分与其他组分具有良好的分离度,线性范围为0.4～10 μg, 加样回收率为102.5%,RSD=2.66%.说明不同产地的三萜类有机酸的含量差别很大.本方法操作简单,结果准确,可用于含2α,3α,19α,23-四羟基乌苏-12-烯-28-羧酸的药物的含量测定.     

Binocular afferents to the salamander pretectum mediate rotation sensitivity of cells selective for visual background motions

The majority (85%) of background motion-sensitive pretectal cells in salamanders was found to be binocularly driven. In 70% of the units the binocularity establishes a rotation selectivity with respect to background pattern-movements. This results in a considerable augmentation of the discharge rate when pattern movement is perceived simultaneously in the temporonasal direction by the contralateral eye and nasotemporally by the ipsilateral eye. The response is depressed when the pattern movement is seen in the same direction by both eyes. It is concluded that the rotation-sensitive cells are mainly excited by contralateral retinal afferents selective for temporonasal movements and inhibited by direct or indirect ipsilateral afferents with the same type of direction selectivity.     

Using switching detection and variational equations for the shooting method

We study in this paper the resolution by single shooting of an optimal control problem with a bang‐bang control involving a large number of commutations. We focus on the handling of these commutations regarding the precise computation of the shooting function and its Jacobian. We first observe the impact of a switching detection algorithm on the shooting method results. Then, we study the computation of the Jacobian of the shooting function, by comparing classical finite differences to a formulation using the variational equations. We consider as an application a low thrust orbital transfer with payload maximization. This kind of problem presents a discontinuous optimal control, and involves up to 1800 commutations for the lowest thrust. Copyright © 2007 John Wiley & Sons, Ltd.     

Facilitation of stimulus detection performance of rats with d-amphetamine: a function of dose and level of training

 Conditions under which amphetamine may facilitate stimulus detection task choice performance in rats were investigated. Rats (n=15) were trained in a two-choice, light-detection task to three successively more stringent criterion levels of task training (minimal, intermediate, and extended) and then tested after administration of saline, 0.25, 0.50, and 0.75 mg/kg d-amphetamine (AMP). For each training level, baseline levels of choice accuracy were maintained at approximately 82% by manipulating the animals’ cue duration. No aspect of performance was enhanced by any dose of AMP after minimal criteria training, and there was a dose-dependent decrease in the number of trials completed. After the intermediate level of training, the 0.25 mg/kg dose of AMP reliably increased choice accuracy, there was no reliable change in choice reaction time, and there was a dose-dependent decrease in the number of trials completed. After the extended training, the 0.25 mg/kg dose of AMP reliably increased choice response accuracy, the 0.25 and 0.50 mg/kg doses of AMP reliably decreased choice reaction time, and there was no reliable change in the number of trials completed at any dose of AMP. These results support the contention that psychostimulants can facilitate the choice performance of rats in stimulus detection tasks if an appropriately low dose is used and the animal’s behavior is strongly controlled by the stimulus-reinforcement contingencies of the task. Received: 24 September 1997 / Final version: 9 May 1998     

高效液相色谱法测定人血清中丙戊酸钠的含量

建立了ＨＰＬＣ方法测定人血清中丙戊酸钠的药物浓度。采用反相柱和乙腈－水（６０∶４０）作为流动相，庚酸作为内标，血样经提取后，用４－溴甲基－６，７－二甲氧基香豆素衍生化，测定波长设在λＳ３２５ｎｍ和λＲ３９８ｎｍ，内标庚酸的保留时间为４．５７ｍｉｎ，丙戊酸钠的保留时间为５．２１ｍｉｎ，线性范围为２～１５０μｇ／ｍｌ。测定了１０名健康受试者单次口服丙戊酸钠片剂后不同时间的血药浓度。     

Cross-calibration of liquid and solid QCT calibration standards: Corrections to the UCSF normative data

Quantitative computed tomography (QCT) has been shown to be a precise and sensitive method for evaluating spinal bone mineral density (BMD) and skeletal response to aging and therapy. Precise and accurate determination of BMD using QCT requires a calibration standard to compensate for and reduce the effects of beam-hardening artifacts and scanner drift. The first standards were based on dipotassium hydrogen phosphate (K₂HPO₄) solutions. Recently, several manufacturers have developed stable solid calibration standards based on calcium hydroxyapatite (CHA) in water-equivalent plastic. Due to differences in attenuating properties of the liquid and solid standards, the calibrated BMD values obtained with each system do not agree. In order to compare and interpret the results obtained on both systems, cross-calibration measurements were performed in phantoms and patients using the University of California San Francisco (UCSF) liquid standard and the Image Analysis (IA) solid standard on the UCSF GE 9800 CT scanner. From the phantom measurements, a highly linear relationship was found between the liquid- and solid-calibrated BMD values. No influence on the cross-calibration due to simulated variations in body size or vertebral fat content was seen, though a significant difference in the cross-calibration was observed between scans acquired at 80 and 140 kVp. From the patient measurements, a linear relationship between the liquid (UCSF) and solid (IA) calibrated values was derived for GE 9800 CT scanners at 80 kVp (IA=[1.15×UCSF]-7.32). The UCSF normative database for women and men obtained with the liquid standard was corrected for use with the solid standard. Proper procedures for cross-calibrating QCT measurements and the appropriate uses of normative data are discussed.     

特发性肺含铁血黄素沉着症二例

特发性肺含铁血黄素沉着症二例王永珍，李金鑫，刘建平，步惠英内蒙古自治区医院特发性肺含铁血黄素沉着症为一种少见的、病因尚不清楚的疾病，国内于１９６０年以来有近百例报导，其特征为肺毛细血管反复出血，渗出的血液发生溶血，含铁血黄素沉着于肺组织而起反应［１］...     

光量子疗法中圆面紫外灯辐照度的定量研究

本文根据光辐射的基本概念，应用数学物理方法，导出了血液辐射治疗仪中带反射罩的紫外线灯的辐照度的计算公式，用ＸＴ－Ａ型紫外光功率计，对ＸＬ－２００型血液辐射治疗仪进行实测，经过计算分析，定出了公式中的待定参数，并应用公式对各实测点进行计算对比，计算值与实测值符合得非常好，发现紫外灯辐射度并简单的指标衰减，为近距离辐照剂量的估算提供了一个有价值的公式，从而将光量子疗法中关于辐照剂量问题的研究定量化。