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71.
100mg香烟烟油,多氯联苯诱导大鼠肝S_9组分中芳香烃羟化酶代谢B[a]P为3-OH-B[a]P的活性分别升高约40,20倍,而代谢B[a] P生成6-OXY-B [a]P自由基产物却仅由多氯联苯诱导的S_9组分作用中才被观察到。 相似文献
72.
The liver first pass effects and bile concentrations of (-)-, (+)- and (+/-)-praziquantel in rabbits
Praziquantel (PQT) is a racemic mixture. Intragastric gavage of (-)-, (+)- and (+/-)-PQT 100 mg/kg were used to study the liver first pass effects in rabbits. HPLC was used to determine the concentration of each compound in the portal and systemic circulation, and in the bile within 4h. The results showed that all drugs were absorbed rapidly from the gut into the portal vein. The serum concentration in the portal vein were similar. However, over 90% of PQT and its enantiomers were extracted in the first passage through the liver. Intrinsic metabolic clearances of the liver of (-)-, (+)- and (+/-)-PQT were 50.3, 174.4 and 52.6 L/h, respectively. The serum concentrations of the three drugs markedly decreased in the systemic circulation, especially that of (+)-PQT. The AUC of (+)-PQT was apparently lower than that of (-)- or (+/-)-PQT. From these results, it is assumed that the first pass effects of PQT and its enantiomers in the liver are pronounced and most likely stereoselective. Also, unchanged PQT and its enantiomers were found in the bile of the rabbits. 相似文献
73.
We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder. 相似文献
74.
持续压力超负荷对兔左心室细胞凋亡的影响 总被引:3,自引:1,他引:2
OBJECTIVE: To study the effect of chronic pressure overload on the apoptosis of the left ventricle myocytes in rabbits. METHODS: Rabbit models of chronic pressure overload-induced heart failure were prepared in which dynamic changes of apoptotic myocytes in the left ventricle were observed by way of terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. RESULTS: Only a few apoptotic cells was observed in the sham-operated group, while in the experimental group, the apoptotic left ventricle myocytes significantly increased after operation, presenting a peak level between day 3 and day 7. Seven days after the operation, the apoptotic myocytes began to decrease and till day 14, the apoptotic cell number had been smaller than that measured on day 1. When signs of heart failure set in, the apoptotic myocytes were again increased (P<0.001). CONCLUSION: During chronic pressure overload, myocyte apoptosis in the left ventricle is elevated at the early stages and undulates subsequently, with the peak occurring before hypertrophy is obvious. 相似文献
75.
Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
76.
77.
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。 相似文献
78.
脊柱推拿时咔哒声响的测量技术分析与设计 总被引:4,自引:0,他引:4
目的 为研究脊住推拿时所发出咔哒声响,提供一套可采集、定位和分析的检测仪器。方法 在回顾咔哒声响测量技术现状的基础上,分析研究了实现声响测量的技术路线,设计了由时钟脉冲发生器、发送/接收接口、校准波发生器、复合传感器、计算机、测定分析软件以及输出部件等组成的声响测量系统。结果 经初步试验,在40cm的距离上测到了关节发出的咔哒声响,说明技术上基本可行。结论 本仪器可以作为脊柱推拿所致咔哒声响的采集、定位和分析系统使用。 相似文献
79.
目的 探讨乙状结肠扭转的病因、诊断及治疗方法。方法 对1990年1月-2002年5月诊治的40例乙状结肠扭转的临床资料进行回顾性分析。结果 术前明确诊断31例、误诊为粘连性肠梗阻3例、绞窄性小肠梗阻2例。消化道穿孔弥漫性腹膜炎2例、腹痛待查2例。行非手术治疗8例,其中4例复发;手术治疗32例,其中单纯复位术11例,2例复发;复位加固定术8例,1例复发;复位加系膜折叠术6例;Hartmann术3例;乙状结肠切除一期吻合术4例。治愈38例,死亡2例。结论 本病的诊断主要依靠临床表现及腹部X线检查。治疗以手术为主,可根据病情及扭转情况选择适当的术式。 相似文献
80.