肺螨病的病理观察

本文报道螨类接种豚鼠气管引起的肺部病变,并对5种常见螨类的致病性进行比较。发现螨类接种后6天豚鼠肺部已形成典型的结节性病灶。结节圆锥形淡黄色,直径1～5mm之间。镜下表现为细支气管炎和细支气管周围炎,肺实质内有明显的异物肉芽肿形成,炎症在螨类接种豚鼠20天时,肺部嗜酸粒细胞浸润不明显,但30或40天时则出现明显的嗜酸细胞浸润,细支气管周围小动脉受到损害,部分小动脉内可见到螨体残骸。5种常见螨炎接种于5组豚鼠可引起大致相同的病变。从而证明豚鼠可作为动物模型以供肺螨病的研究,同时也证明5种常见贮藏螨具有相同的致病性。     

Clinical MR imaging with a Helmholtz-type surface coil

Limited-field-of-view radio-frequency receiver antennas provide improved near-field sensitivity for magnetic resonance imaging by decreasing the antenna volume. The Helmholtz-type surface coil, consisting of two flat rings, is an organ-encompassing antenna that takes advantage of this principle to yield an improved signal-to-noise ratio (S/N). The coil was tested in a group of 50 patients and 16 healthy volunteers. Images obtained with the Helmholtz coil demonstrated quantitatively superior S/N of 2.2-fold or greater than that of comparison body coil images, as well as qualitatively superior anatomic resolution.     

A system for tissue-specific gene targeting: transgenic mice susceptible to subgroup A avian leukosis virus-based retroviral vectors.

Avian leukosis viruses (ALVs) have been used extensively as genetic vectors in avian systems, but their utility in mammals or mammalian cell lines is compromised by inefficient viral entry. We have overcome this limitation by generating transgenic mice that express the receptor for the subgroup A ALV under the control of the chicken alpha sk-actin promoter. The skeletal muscles of these transgenic animals are susceptible to efficient infection by subgroup A ALV. Because infection is restricted to cell lineages that express the transgene, the method has utility for studies of development and oncogenesis and will provide models for tissue-specific gene therapy.     

Effect of food on pharmacokinetics of cefuroxime axetil in Chinese subjects.

The effect of food on the pharmacokinetics of cefuroxime axetil was studied. Twelve healthy male subjects were included in this study. They were given single oral 500 mg doses of cefuroxime axetil alone or with food based on a balanced two-way crossover design. Plasma cefuroxime concentrations were assayed by the high performance liquid chromatographic method. When the drug was given alone, the area under the curve (AUC) was 15.77 +/- 4.12 mg*h/L, Cmax was 4.20 +/- 1.05 mg/L, Tmax was 2.36 +/- 0.84 h, T1/2 was 1.56 +/- 0.26 h, and Clp/F was 34.13 +/- 10.39 L/h; 45.12 +/- 9.59% of the dose was recovered in the urine within 24 hours, and the renal clearance was 12.58 +/- 4.41 L/h. When the drug was given with food, the corresponding AUC was 23.46 +/- 4.57 mg*h/L, Cmax was 7.10 +/- 1.41 mg/L, Tmax was 2.04 +/- 1.32 h, T1/2 was 1.40 +/- 0.23 h, and Clp/F was 21.93 +/- 5.18 L/h; the 24-hour urinary recovery was 69.33 +/- 6.13% and the renal clearance was 12.58 +/- 2.99 L/h. The above pharmacokinetic parameters obtained from the two regimens were compared by two-way ANOVA corrected for the change-over effect. No significant difference was found for Tmax, T1/2 or renal clearance (p > 0.05). Higher AUC, Cmax, urinary recovery and lower Clp/F values were observed for the regimen with food (p < 0.05). The plasma drug concentrations resulting from the regimen with food were higher throughout the 12-hour sampling period when compared to the regimen without food.(ABSTRACT TRUNCATED AT 250 WORDS)     

实验性糖尿病大鼠肾脏损害和脂质过氧化物水平的动态研究

动态观察实验性糖尿病大鼠于发病后２、４、６、１２、和１６周肾脏损害指标和肾脏脂质过氧化物（ＬＰＯ）水平的变化。结果表明，发病后各观察时间．或糖尿病大鼠２４ｈ尿Ａｌｂ、β２──ＭＧ排泄量和尿ＮＡＧ活性均明显增高，而２４ｈ尿ＴＨＰ排泄量显著降低，肾脏ＬＰＯ水平明显升高。其中尿ＮＡＧ活性、ＴＨＰ排泄量和肾脏ＬＰＯ水平均随病程延长而更趋明显。这些结果提示，在糖尿病早期除有肾小球功能损害外，肾小管也明显受损，过氧化损伤在糖尿病肾病发病中可能是重要因素之一。尿Ａｌｂ、β２──ＭＧ、ＴＨＰ含量和ＮＡＧ活性可作为糖尿病肾病早期肾损害的敏感指标。     

5-HT3 agonist 2-methylserotonin as a training drug in discrimination studies.

Using a standard two-lever operant procedure, rats were trained to discriminate 5 mg/kg of the 5-HT3 agonist 2-methylserotonin (2-Me 5-HT; ED50 = 2.6 mg/kg) from saline using a VI 15-s schedule of reinforcement. The 2-Me 5-HT stimulus did not generalize to the 5-HT1/5-HT2 agonist 5-methoxy-N,N-dimethyltryptamine, but did generalize to the new 5-HT3 agonist 1-(m-chlorophenyl)biguanide (ED50 = 1.6 mg kg). The 5-HT3 antagonist ICS 205-930 potently antagonized the 2-Me 5-HT stimulus (ID50 = 0.001 mg/kg), whereas its quaternary amine analog, which does not readily penetrate the blood-brain barrier, failed to completely antagonize the 2-Me 5-HT stimulus at a 10,000-fold higher dose. The results of the present investigation show that 2-Me 5-HT serves as a discriminative stimulus in rats when paired with saline and suggest that its stimulus properties are likely mediated via a central 5-HT3 mechanism. As such, this is the first demonstration that a 5-HT3 agonist can be used as a training drug in drug discrimination studies.     

替硝唑的合成

以甲硝唑为原料，经过氯化、硫醚化和气化反应合成了替硝唑，经元素分析和１Ｈ－ＮＭＲ证实了结构。