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1. Orchidectomy results in long‐term testosterone deprivation similar to that observed in male clinical pathologies, such as hypogonadism and age‐related reductions in plasma testosterone concentrations. Although the vascular effects of these sorts of hormone deprivations are known in arteries, they have not been studied to the same extent in veins. 2. The aim of the present study was to determine the effect of orchidectomy, with or without subsequent testosterone replacement (started 23 days after orchidectomy; 10 mg/kg, i.m., testosterone propionate once every 5 days for 3 weeks), on responses of rat isolated portal veins and vena cavae to exogenous phenylephrine (PE). Isolated vessels were mounted in an organ bath and concentration–response curves constructed to PE (10?10–10?4 mol/L), endothelin (ET; 10?10–10?5 mol/L) and KCl (10?2–1.2 × 10?1 mol/L; as a control). 3. Orchidectomy had no effect on contractile responses of either the portal vein or vena cava to KCl. However, orchidectomy enhanced the maximum response (Rmax) of the portal vein, but not the vena cava, to PE. Testosterone replacement had no effect on these responses. The effects of orchidectomy on the Rmax to PE in portal veins were not altered by the nitric oxide synthase inhibitor NG‐nitro‐l‐ arginine methyl ester (10?4 mol/L) alone or combined with 10?5 mol/L indomethacin (a non‐selective cyclo‐oxygenase inhibitor), but they were abolished following treatment of isolated vessels with the ETA and ETB receptor antagonists BQ‐123 and BQ‐788 (both at 10?6 mol/L). Orchidectomy did not alter portal vein responses to the application of exogenous ET. 4. The results of the present study indicate that orchidectomy‐induced decreases in plasma testosterone can increase the venoconstrictor effects of PE on the portal vein and that this effect involves activation of both ETA and ETB receptors by locally produced ET.  相似文献   
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Cobb  SR; Mehringer  CM 《Radiology》1987,162(2):521-522
Wallerian degeneration in the corticospinal tract was demonstrated by magnetic resonance (MR) imaging in a patient with Schilder disease. The histochemical stages of myelin breakdown that allow its demonstration by MR imaging are reviewed.  相似文献   
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目的 报告成功实施腹腔镜迷你胃旁路术治疗单纯性肥胖并2型糖尿病病人1例。方法 第二军医大学附属长海医院微创外科于2007年11月对1例伴有2型糖尿病的单纯性肥胖症病人行腹腔镜迷你胃旁路术。结果 病人手术顺利,手术时间135min,术中出血20mL。术后30d内无手术并发症,随访30d,体重下降15kg,体重指数(BMI)减少4.9。术后第8天停用一切降糖药物,各项糖尿病检查指标均正常。结论 腹腔镜迷你胃旁路术是相对安全、简单的术式,近期减重效果良好,对2型糖尿病具有很好的治疗效果。  相似文献   
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目的:观察新生大鼠缺氧缺血性脑损伤后,海马发育过程中N-甲基-D-天冬氨酸受体的远期表达变化。方法:实验于2006-03/06在解放军第三军医大学新桥医院中心实验室完成。选用新生7日龄SD大鼠72只,按随机数字表法分为缺氧缺血性脑损伤组和假手术组,每组36只。各组又分为生后15d(n=6)、22d(n=6)、29d(n=6)、36d(n=12)及43d(n=6)5个时相点。①参照Rice法通过结扎7日龄大鼠左侧颈总动脉,吸入氧气体积分数为0.08的氮氧混合气,制成缺氧缺血性脑损伤模型,出现自发或夹尾左旋则证明模型制作成功。假手术组仅切开颈部皮肤,暴露左侧颈总动脉。②应用免疫组织化学法检测缺氧缺血后不同时点两组大鼠脑海马CA1区N-甲基-D-天冬氨酸受体NR1亚单位的表达(n=6),测量平均灰度值,灰度值越低,蛋白表达越强;生后36d时相点大鼠(n=6)利用Morris水迷宫测定学习记忆能力;最后应用电镜观察生后36d大鼠海马突触结构。结果:72只大鼠,全部进入结果分析,无脱失。①生后22-43d缺氧缺血性脑损伤组大鼠(缺氧缺血后15-36d)脑海马CA1区NR1平均灰度值分别为167.69±6.48,174.57±4.81,179.30±5.92,176.50±5.93,均显著高于同日龄假手术组148.96±4.91,151.17±6.37,152.06±9.86,156.32±6.86(P均<0.01)。②Morris水迷宫实验中,缺氧缺血性脑损伤组大鼠逃避潜伏期显著长于假手术组(48.87±9.47)s,(11.97±2.20)s,(P<0.01);原平台象限游泳距离/总游泳距离的百分比显著低于假手术组(14.45±3.85)%,(62.20±8.74)%(P<0.01)。③生后36d(缺氧缺血后29d),透射电镜下缺氧缺血性脑损伤组大鼠患侧海马突触后膜致密物较假手术组明显减少。结论:新生大鼠缺氧缺血性脑损伤后期存在海马N-甲基-D-天冬氨酸受体的表达下调,可能对大鼠远期空间学习记忆产生一定影响。  相似文献   
109.
We describe a patient undergoing elective surgery for treatment of an abdominal aortic aneurysm in whom an abrupt change in the contour of the pulmonary artery pressure (PAP) trace indicated the development of an intermediate (20 mm Hg) V wave in the pulmonary artery wedge pressure (PAWP) trace. As the PAP trace is displayed continuously, attention to its contour may allow for early detection of changes to the underlying PAWP trace.FC Anaesth  相似文献   
110.
The fourth component of human complement (C4) is one that is essential to the antibody-mediated classical activation pathway. C4d, present on all normal and most patient red cells (RBCs), may be detected by the human antisera anti-Rodgers (Rg) and -Chido (Ch). A study has been made of the Rg/Ch antigens on normal and patient RBCs in an attempt to understand the mechanism by which C4 is bound to normal RBCs in the absence of RBC antibodies (Abs). Because RBCs from C1q-deficient patients express Rg/Ch, it seems that C1q is not essential for C4 binding. Treatment of normal RBCs with proteolytic enzymes, including trypsin, eliminated positive reactions with anti-Rg/Ch even though the C4d fragment is considered to be resistant to cleavage by trypsin. By correlating agglutination reactions with numbers of bound C4d and C3d molecules, it is evident that both C4d and C3d were affected by trypsin treatment and that anti-Rg/Ch were not capable of agglutinating RBCs with less than 50 molecules of bound C4d. It is concluded that trypsin-sensitive and -insensitive RBC membrane structures may both act as acceptors for C4. RBCs with null phenotypes of the major blood group systems all expressed Rg/Ch antigens, so none of the structures that carry these antigens act preferentially as acceptors for C4.  相似文献   
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