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21.
The aim of this study was to elucidate the vasodilator mechanisms of barbiturates. In helical strips of dog mesenteric artery, the effects of pretreatment with thiopentone and pentobarbitone on the contractions induced by KCl (2.0 x 10(-2) M) and norepinephrine (10(-5) M) in normal bathing fluid, and those induced by norepinephrine and caffeine (2.5 x 10(-2) M) in Ca(++)-free fluid were tested, and their effects on caffeine-induced contractions in skinned strips were also examined. Thiopentone, at concentrations over 10(-4) M, inhibited the KCl-induced contractions in normal bathing fluid and those induced by caffeine in Ca(++)-free fluid and, at concentrations over 3 x 10(-4) M, inhibited norepinephrine-induced contractions in normal and Ca(++)-free bathing fluids significantly. Pentobarbitone, at concentrations over 3 x 10(-4) M, inhibited KCl- and norepinephrine-induced contractions in normal bathing fluid significantly, whereas contractions in Ca(++)-free fluid induced by norepinephrine and caffeine were inhibited only by a high concentration (10(-3) M) of pentobarbitone. Caffeine-induced contractions of chemically skinned fibres were more susceptible to inhibition by thiopentone than by pentobarbitone. These results suggest that the vasodilator effect of thiopentone is mediated via its intracellular inhibitory effect and that, in contrast, the vasodilator effect of pentobarbitone can be attributed mainly to its Ca(++)-channel blocking action.  相似文献   
22.
流行性乙型脑炎病毒结构蛋白编码基因的重组构建   总被引:1,自引:1,他引:0  
目的:建立流行性乙型脑炎病毒(JEV)C、prME,E等结构蛋白编码基因克隆.方法:病毒感染C6/36细胞,RT-PCR法依次获取该病毒结构蛋白基因并进行DNA测序分析,PCR克隆法将PCR产物分别构建于真核表达载体pcDNA 3.1的BamHI与EcoRI酶切位点并依次命名为pJC、pJME与pJE,通过DNA测序、电泳以及限制性内切酶分析加以鉴定.结果:JEV C、prME与E基因片段分别为380、2001以及1 500bp,各基因测序结果与发表的JEV JaGAr-01株相对应序列相一致,从重组质粒释出的插入子分别与各基因大小相符合.结论:pJC、pJME与pJE重组质粒分别含有C、prME与E蛋白编码基因.  相似文献   
23.
OBJECTIVE: It is controversial whether a systematic mediastinal lymph node dissection (MLND) needs to be performed in all patients with stage I lung cancer. The present study was done to examine the new sentinel lymph nodes hypothesis based on the lobe of the primary tumor. METHODS: In our first study, the lymph node (LN) metastases were assessed in 291 stage I non-small cell lung cancer (NSCLC) patients who had a major lung resection with a systematic mediastinal lymph node dissection. We evaluated the validity of using our new sentinel lymph nodes method based on the lobe of the primary tumor as follows: the pretracheal (#3), tracheobronchial (#4), and hilar nodes (#10) for right upper lobe tumors; #4, subcarinal (#7), and #10 for middle lobe tumors; the subaortic (#5), paraaortic (#6), and #10 for left upper lobe tumors; and the #7, #10, and interlobar nodes (#11) for tumors in either lower lobes. In the second study, we performed a lobectomy with new sentinel node sampling in 64 patients with preoperative complications. If all of the sampling nodes showed no metastases on frozen section diagnosis, systematic node dissections were not performed. RESULTS: Six of 291 patients in the first study had skip metastases that did not involve the new sentinel nodes; 5 of the 6 patients had macroscopic pleural invasion. Thus, we defined pleural invasion as an exclusion criterion for the second study. In the second study, the median follow-up time was 39 months. Metastatic lymph nodes were detected in 11 of 64 patients. Fifty-three patients (83%) had no metastasis in the sampled nodes, and, therefore, a mediastinal lymph node dissection was not done. The morbidity rate in the sampling group was 36%, and there was no mortality. In the sampling group, local recurrences were observed in two patients, distant metastases in eight, and carcinomatous pleuritis in one; the overall 5-year survival rate was 82%. CONCLUSIONS: We found that it is possible to perform a less invasive lymphadenectomy for patients with stage I lung cancer using intra-operative sampling of new sentinel lymph nodes.  相似文献   
24.
Preconditioning of the brain with sublethal ischemia induces tolerance to subsequent lethal periods of ischemia (ischemic tolerance). In this study, we used NADPH-diaphorase histochemistry to investigate the postischemic changes of nitric oxide synthase (NOS) in the hippocampus in a rat model of cerebral ischemia and ischemic tolerance. Forebrain ischemia was induced by 4-vessel occlusion for 3 min as an ischemic preconditioning. Three days after the preconditioning or sham operation, second ischemia was induced for 6 min. A transient increase in NADPH-diaphorase activity, beginning after 2 h and maximal after 1 day, was observed in CA1 pyramidal neurons of rats subjected to 3 min of preconditioning ischemia as well as 6 min of subsequent ischemia both with and without preconditioning. In addition, expression of NADPH-diaphorase activity was seen in reactive glial cells in the damaged CA1 region of animals subjected to 6 min of ischemia without preconditioning. Thus, direct involvement of increased NADPH-diaphorase activity in ischemic tolerance was not suggested because the increased NADPH-diaphorase activity preceded the induction of ischemic tolerance which takes place 1–7 days after preconditioning. However, the present findings suggest that the induction of neuronal NADPH-diaphorase activity occurs in response to cerebral ischemia.  相似文献   
25.
We investigated the effects of a novel platelet-activating factor (PAF) receptor antagonist, CIS-19 [cis-2-(3, 4-dimethoxyphenyl)-6-isopropoxy-7-methoxy-1-(N-methylformamido)-1, 2, 3, 4-tetrahydronaphthalene], on PAF-, histamine-, substance P- and antigen-induced bronchoconstriction and microvascular leakage, as well as PAF- and antigen-induced bronchial hyperreactivity to methacholine in urethane-anesthetized guinea-pigs. Administration of CIS-19 (0.5–5 mg/kg, i.v.) inhibited the increase in lung resistance induced by PAF (30 ng/kg, i.v.) in a dose-dependent manner, but failed to inhibit the increase induced by histamine (30 μg/kg, i.v.) or substance P (6.5 μg/kg, i.v.). CIS-19 (5 mg/kg, i.v.) did not inhibit the increase in lung resistance induced by ovalbumin (2 mg/kg, i.v.) in actively sensitized guinea-pigs. PAF (30 ng/kg, i.v.)-induced microvascular leakage, measured by the extravasation of Evans blue dye, was dose-dependently inhibited by CIS-19 (0.5–5 mg/kg, i.v.) in the trachea, main bronchi and intrapulmonary airways, but it did not affect histamine (30 μg/kg, i.v.)- or substance P (6.5 μg/kg, i.v.)-induced microvascular leakage at all airway levels. CIS-19 (2.5 and 5 mg/kg) did not affect ovalbumin (2 mg/kg, i.v.)-induced microvascular leakage in all airway levels in actively sensitized guinea-pigs. CIS-19 (2.5 and 5 mg/kg, i.v.) significantly inhibited PAF-induced enhancement of the bronchial response to methacholine, but had no effect on ovalbumin (0.05 mg/kg, i.v.)-induced bronchial hyperreactivity in actively sensitized guinea-pigs. It is concluded that CIS-19 is a potent PAF receptor antagonist which inhibits PAF- but not antigen-induced bronchoconstriction, microvascular leakage and bronchial hyperreactivity. These results suggest that PAF plays little or no role in early airway responses following antigen challenge. Received: 29 April 1996 / Accepted: 10 October 1996  相似文献   
26.
A 60-year-old Japanese man was hospitalized because of urinary leakage from the anus on October 3, 1994. Retrograde urethrography detected a fistula between the bulbous urethra and the rectum. Urethrocystoscopy revealed a tumor on the urethrorectal fistula. Tumor biopsy showed a well differentiated adenocarcinoma. Cystourethrectomy with fistulectomy, and ileal conduit urinary diversion were performed. Pathological examination revealed primary adenocarcinoma in the fistula with invasion to the prostatic urethra and bladder wall. The patient showed no evidence of a recurrence as of August, 1996.  相似文献   
27.
Ductus arteriosus aneurysm is rare in adults and preoperative diagnosis has not been usually done. We report 2 cases of adult type ductus arteriosus aneurysm. In both cases, 3D computed tomographic scanning showed a saccular aneurysm originating from the distal aortic arch toward the left pulmonary artery, which had a notching in the orifice of the aortic side. They were successfully treated surgically though one was a ruptured aneurysm to the left pulmonary artery. In these cases, 3D-CT scan was of great value in the preoperative diagnosis of the ductus arteriosus aneurysm.  相似文献   
28.
The patient was a 48-year-old male who was diagnosed with unstable angina. He had worsening cardiogenic shock during coronary angiography. Emergency coronary artery bypass grafting (CABG) was performed. He had a methicillin-resistant Staphylococcus aureus (MRSA) mediastinitis on day 22 after CABG. Drains were placed in the anterior mediastinum, left thoracic cavity, and abscess cavity, and another drain was placed in the mediastinal space for continuous cleansing with povidone iodine, oxydol. For antibiotics, teicoplanin (TEIC) was administered intravenously and to the local site via the cleansing drain for about one month. No MRSA was detected by culture in discharges from the mediastinal drain. Inflammatory findings were improved, and the patient was discharged and resumed everyday life without recurrence of inflammation as of eight months. Although the number of cases of MRSA mediastinitis is small and accumulation of cases is necessary to investigate therapeutic methods and selection of antibiotics, our department will select closed continuous cleansing and TEIC for antibiotics as the first choice for MRSA mediastinitis, and accumulate cases to investigate its efficacy.  相似文献   
29.
30.
We reported a case of the biliary cystadenoma of the liver. The cystic mass had labulation and septation and showed marked hyperintensity on T1-weighted images and hypointensity on T2-weighted images; MR findings were very unusual for cystadenoma. The content of the cystic mass was jelly-like, thick mucinous fluid without intracystic hemorrhage. We concluded that these unusual signal intensities of the cyst were due to hyperproteinous mucinous fluid.  相似文献   
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