RP-HPLC法测定家兔血浆中甲苯喹哌浓度和药代动力学参数

本文建立了以紫外230nm波长检测的反相高效液相色谱法(RP-HPLC)测定家兔血浆中甲苯喹派浓度。填料使用LiChrosorb RP-C18,流动相为甲醇—水—三乙胺—磷酸(63:37:1:0.8 v/v),血样(或尿样)经碱化后用乙醚提取,再以0.2 mol/L硫酸回提,进样。方法回收率为99.84±3.10(SD)%;天内、天间精密度平均CV为4.12%及3.95%(n=5);最低检测限3ng.经提取的标准线性浓度在25～2000 ng/ml范围内,Y=0.002865X-0.01346,r=0.9999,内源性物质及可能的合并用药不干扰色谱测定。文内用质谱法鉴定血样中甲苯喹哌色谱峰纯度,并由尿样分析对其主要代谢物予以初步验证。本法可应用于药代动力学参数测定。家兔按8mg/kg静注后,药—时曲线符合二室模型T_1/2=4.8008±1.1522(SD)h。     

11β-HYDROXYSTEROID DEHYDROGENASE TYPE I ENZYME IN THE HEARTS OF NORMOTENSIVE AND SPONTANEOUSLY HYPERTENSIVE RATS

1. The enzyme 11β-hydroxysteroid dehydrogenase (11βHSD) converts glucocorticoids to their inactive 11-keto metabolites. The ubiquitous expression of the NADP-dependent isoform (11βHSD1) suggests an important role in modulating glucocorticoid action, but little is known about 11βHSD1 gene expression and enzymatic activity in the rat heart. 2. In the present study rat cardiac 11βHSD1 activity and ontogeny of gene expression have been characterized. The addition of NADP, but not NAD, to heart homogenates resulted in significant increases in the metabolism of both corticosterone and cortisol, with the former substrate displaying far greater metabolism. Both 11βHSD1 gene expression and enzyme activity increased in parallel from low levels at 1 week of age to maximal levels at 8 weeks, with no further change by 16 weeks of age. 3. We also compared theactivity of 11βHSD1 in the hearts of male and female spontaneously hypertensive rats (SHR) with normotensive Wistar-Kyoto (WKY) controls. Enzyme activity in the pooled atria of female SHR was significantly higher than in male SHR atria (7.6±0.6% conversion of corticosterone vs 4.5±0.5%; P < 0.05). The left ventricles of female WKY rats contained significantly less 11βHSD activity than either male WKY rats or female SHR (8.6±0.8% conversion vs 17±1.4 and 13.6±0.5%, respectively; P < 0.05). In the right ventricle, female WKY rats also had significantly less enzyme activity than either female SHR or male WKY rats (4.9±0.7 vs 10.0±1.7 and 10.2±1.4%; P<0.05). 4. These results clearly show that the rat heart contains significant amounts of the 11βHSD1 enzyme and that this activity is sexually dimorphic. Furthermore, significant differences were observed between a normotensive and hypertensive strain of rat. The relevance of these observations to the aetiology and maintenance of hypertension remains to be explored.     

胃黏液屏障与胃黏膜保护的研究进展

胃黏液屏障是指覆盖于胃黏膜上皮细胞表面的一层连续性凝胶层,由糖蛋白、水、电解质、肽以及脂类组成.胃黏液凝胶层呈一定的厚度变化,黏蛋白多聚结构稳定,具有较高的黏滞性和水不溶性.能不断更新,处于分泌和降解的动态平衡之中.作为胃黏膜保护的第一道屏障,胃黏液凝胶层具有润滑作用,拮抗H 逆弥散和消化酶的消化作用,参与对损伤因子的防御和损伤后修复.其独特的生理特征和生理作用在胃黏膜保护中起重要的作用.     

远程二维核磁共振和NOE差谱法研究新生物碱马尾杉碱N的结构

自华南马尾杉[Phlegariurus fordii(Baker)Ching]中分得新生物碱—马尾杉碱N(Ⅰ)。它含有七个季碳。本工作采用远程¹³C—¹HCOSY和远程增强型¹H—¹HCOSY新技术与NOE差谱相配合的方法成功地连接被季碳和杂原子分隔开的自旋系统,推定了其结构。     

IDENTIFICATION OF SUBSETS OF PATIENTS WITH GRAVES''DISEASE BY CLUSTER ANALYSIS

We have applied cluster analysis methods to forty-nine laboratory and clinical characteristics (including 26 HLA-A, B antigens) observed in 196 Graves' disease patients. Three subgroups could be identified: group I (seventy-nine patients) had small goitres, low indices of autoimmunity and a tendency to remission with medical treatment; group IIa (twenty-nine patients) had clinical and laboratory features of 'Hashitoxicosis'; Group IIb (eighty-four patients) had a high incidence of ophthalmopathy, familial aggregation, marked evidence of autoaggression and a tendency to relapsing hyperthyroidism. The prevalence of HLA-B8 was 8.9% in group I, 20.7% in group IIa and 86.9% in group IIb. This study demonstrates that Graves' disease can be subdivided using cluster analysis into clinically relevant subgroups which are further distinguished by their correlation with HLA-B8. Possible immunological bases for these observed patterns are discussed.     

Recurrent shoulder dislocation after surgical repair: double-contrast CT arthrography. Work in progress

Nine cases of recurrent postoperative shoulder instability, resulting from failed surgical repair, were studied with double-contrast computed tomography (CT) arthrography. Repeat operations in seven cases showed excellent correlation between CT and surgical anatomic findings. CT arthrography was useful in confirming the direction of instability, particularly of the posterior and multidirectional types. Capsular laxity, subscapularis muscle and tendon abnormalities, and Bankart lesions that were either recurrent or not identified during previous operations were the most common causes of recurrent dislocations. The precise identification of the soft-tissue and bone abnormalities responsible for shoulder instability augmented clinical evaluation and aided preoperative planning.     

高功率激光-血管-组织相互作用的红外试验

目的:通过一系列活体和体外实验来考察激光诱导间质热疗过程中血管及器官受高功率激光作用时的温度场发展规律。方法:实验性家兔1只,麻醉状态下应用波长为10.6mm的KD-Ⅲ型CO2激光器(北京科电微波电子有限公司生产)在不同功率激光照射其耳部不同部位,观察血管稀疏区与丰富区在激光照射下的反应。隔2d,将其麻醉处死,取出胃、肝、肺、肾、心等不同器官,进行激光照射。实验中引入红外成像仪来定量刻画被测对象表面的瞬态温度分布图像。结果:①当激光热量不足以完全切断血管时,血管丰富组织区的复温能力强于血管稀疏区;当激光准确作用于主血管并且达到一定能量时,不仅下游供血及加热可被切断,且上游供血也会受到影响。②在相同的激光频率、功率及作用时间下,胃部的穿透最深,肾部温度变化率最大。结论:①组织局部的血液灌注率会影响激光作用的效果。②不同器官由于热容量不同,且对激光的反射和吸收率存在差异,导致激光穿透厚度及组织温度变化的幅度不同。