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81.
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   
82.
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   
83.
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   
84.
85.
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   
86.
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   
87.
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   
88.
以头孢呋辛钠为原料,从制备(R,S)-乙酸1-溴乙酯开始。经酯化反应的溶剂沉淀过程无须分离直接制得高纯度非晶型的头孢呋辛酯。本制备方法简便,适于工为化生产。  相似文献   
89.
葛根对小白鼠免疫功能的影响   总被引:8,自引:1,他引:7  
从免疫学方面探讨中药葛根的强身健体作用。方法 :用 10 0 %葛根水浸出液定期给小鼠灌胃 ,然后检测小鼠抗体产生能力、淋巴细胞转化率、巨噬细胞吞噬的功能。结果 :用药组小白鼠以上免疫学指标均有显著增强作用 ,与对照组相比有非常显著性差异 (P <0 .0 1)。未见有副作用。结论 :口服葛根可明显增强机体免疫功能。  相似文献   
90.
In situ hybridization of prostate-specific antigen mRNA in human prostate.   总被引:4,自引:0,他引:4  
Prostate-specific antigen (PSA) mRNA was detected by in situ hybridization utilizing a 428 base pair [35S]-labelled cDNA probe from the 3' noncoding region of the PSA gene. Thirty six fresh surgical specimens were collected from patients undergoing radical retropubic prostatectomy for carcinoma of the prostate. Quantitative analysis of the levels of PSA mRNA in both the benign and malignant tissues was performed using an IBAS 2000 Image Analysis System. The results of this study demonstrated that there is a significant decrease in the expression of PSA mRNA in the carcinoma tissue when compared to the benign epithelium. The average binding (number of silver grains/1 x 10(4) microns. 2) for 20 specimens of malignant epithelium was 475 +/- 161 and 586 +/- 140 for 16 specimens of benign epithelium (p less than 0.05). Eleven patients had both benign and malignant tissue from the same surgical specimen available for study. From these paired specimens, the PSA mRNA expression was also significantly reduced in the malignant epithelium when compared to the benign epithelium, 445 +/- 162 and 588 +/- 135 respectively (p less than 0.005). The PSA protein was detected using a monoclonal antibody to PSA with an immunohistochemical staining technique. The PSA protein expression paralleled the expression of the PSA mRNA in the majority of the tissue sections. Many of the tumor specimens showed a heterogeneous expression of PSA, whereas all of the benign epithelium had a uniform high level of PSA expression. In conclusion, PSA mRNA and protein are located only within the glandular epithelial tissue, the expression of PSA protein parallels that of the PSA mRNA, and both the PSA protein and PSA mRNA are significantly decreased in the malignant epithelium when compared to benign prostatic epithelium.  相似文献   
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