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51.
52.
Measurement of individual kidney glomerular filtration rate (IKGFR) from the gamma-camera technetium 99m diethylene triamine penta-acetic acid (99mTc-DTPA) renogram requires a continuous measurement of arterial activity. This is usually based on a region of interest (ROI) placed over the cardiac blood pool on the posterior view, with the assumption of negligible contamination from activity in the extravascular space of the chest wall. By injecting a small dose of technetium 99m human serum albumin (HSA) before the99mTc-DTPA in 12 patients undergoing routine renography, the contribution of extravascular activity to the total signal recorded over the cardiac blood pool was calculated to be 11.0% (SE 2.1%) 1.5 min after DTPA injection, rising to 35.1% (SE 2.5%) at 15 min. Subtraction of the time-activity curve recorded from a ROI of the same size over the right lung generated a pure blood signal as shown by almost identical HSA/DTPA signal ratios recorded in blood samples taken 5 min after HSA and 15 min after DTPA and from the gamma-camera at the corresponding times. The effect of using a cardiac blood pool time-activity curve uncorrected for extravascular activity was to overestimate IKGFR by an average factor of 1.17 (SE 0.03). Offprint requests to: A.M. Peters  相似文献   
53.
Summary The effects of the competitive angiotensin II antagonist saralasin (1-sarcosine-8-alanine-5-isoleucine-angiotensin II) on renal function in healthy rats and in rats with myohemoglobinuric acute renal failure were studied. Acute renal failure was induced by an intramuscular injection of 50% glycerol (10 ml ·kg–1). Functional impairment of the glycerol treated animals consisted in a decrease of renal blood flow (electromagnetic flowmeter) and GFR and in an increase of urine volume and arterial blood pressure.In healthy rats saralasin (6 g·kg–1·min–1 i.v.) had no renal effects by itself but antagonized the angiotensin II (200 ng·kg–1·min i.v.) induced fall of renal blood flow and GFR and the increase of arterial blood pressure. Given to glycerol treated animals saralasin did not induce any change of arterial blood pressure, renal blood flow, GFR or the urinary excretion of fluid and sodium.Supported by Deutsche Forschungsgemeinschaft  相似文献   
54.
目的从两株微小亚历山大藻(Alexandrium minutum Halim)中分离纯化膝沟藻毒素(Gonyautoxins).方法用胶滤层析、离子交换层析等方法从人工培养的两株微小亚历山大藻酸酒精萃取物中分离纯化膝沟藻毒素,再用HPLC法对毒素进行定性定量测定.结果从两株藻株培养液中均分离得到膝沟藻毒素GTX-4,GTX-1,GTX-3,GTX-2,其中Amtk4藻株的毒素含量为Amtk2的近10倍.结论微小亚历山大藻Amtk4藻株适于制备膝沟藻毒素.  相似文献   
55.
凝胶过滤色谱和Bradford法测定发酵类抗生素中蛋白残留量   总被引:4,自引:0,他引:4  
目的以发酵类抗生素盐酸林可霉素为例,建立一个快速、简单、灵敏度高的可用于发酵类抗生素中蛋白残留量控制的方法.方法利用凝胶过滤色谱(GFC)首先将蛋白质与抗生素分离,收集蛋白组分,再利用蛋白检测方法Bradford法(考马氏亮兰染色法)对残留的蛋白进行定量;色谱柱为SuperdexTM Peptide HR 10/30;检测波长为214 nm;流速为1 mL·min-1;流动相为0.01 mol·L-1磷酸盐缓冲液;进样量为500 μL.结果本方法蛋白(BSA)的平均回收率大于90%,蛋白浓度在0-12 μg·mL-1之间符合曲线方程y=-0.002 4x2 0.064 2x 0.002 9,r2=0.999 9; 检测限为3 ng·mL-1(相当于盐酸林可霉素中蛋白的残留量为7×10-7).结论本方法简便,快速,灵敏,可以用于控制发酵类抗生素中蛋白的残留量.  相似文献   
56.
Yeh JH  Chiu HC 《Artificial organs》2000,24(9):705-709
Hypotension is an uncommon complication of procedures involving extracorporeal circulation, including plasmapheresis. From November 1993 to March 1999, we treated 139 patients who underwent a total of 1,137 sessions of double filtration plasmapheresis (DFP). Hypotension was defined as a systolic blood pressure (BP) < 80 mm Hg or any decrease of systolic BP with systemic reactions. A total of 17 (1.5%) episodes of hypotension were documented in 15 patients during the study period. Hypotensive episodes occurred in 2.3% of patients with inflammatory neuropathy, 1.2% of patients with myasthenia gravis, and 1.2% of patients with all other medical diseases. Involvement of the autonomic nerve system (ANS) and a low baseline BP were associated with the occurrence of hypotension. Eight (47%) of 17 episodes were symptomatic and 2 were complicated with seizure. Patients with symptomatic hypotension had a higher level of systolic BP prior to DFP and a larger drop of systolic BP and pulse rate during hypotensive attacks compared to asymptomatic patients. Most hypotensive episodes were resolved briefly after intravenous infusion of saline within 30 min. Eight (47%) of the hypotensive episodes occurred during the first session of DFP treatment. Twelve (71%) of 17 episodes occurred during the last half period of treatment; 6 of them were noted during the terminating stage of DFP. In conclusion, in this series plasmapheresis-related hypotension occurred in 1.5% of DFP sessions and had a higher prevalence in patients with ANS instability and low BP. Extra caution in monitoring BP during DFP therapy is warranted in these vulnerable patients, especially during the termination phase of the first DFP session.  相似文献   
57.
目的观察血管紧张素转化酶抑制剂(ACEI)———开搏通对糖尿病肾小球高滤过患者的短期治疗作用。方法对27例尿白蛋白阴性、血压正常、高肾小球滤过率的糖尿病患者,采用开搏通治疗1个月,比较治疗前后肾小球滤过率(GFR)与尿白蛋白排泄率(UAER)、血压等指标变化,评价开搏通逆转糖尿病肾小球高滤过的临床效果。结果GFR从175.1±24.3ml/min降至138.5±30.0ml/min(P<0.01),27例糖尿病患者中22例GFR明显下降,4例无明显变化,1例略升高;UAER较治疗前明显下降(P<0.05);治疗前后血压均无明显变化。结论开搏通有明显逆转糖尿病患者高肾小球滤过率的作用,且不依赖于血压的下降,具有独特的肾脏保护作用。  相似文献   
58.
丝裂霉素C与青光眼滤过泡并发症的相关关系   总被引:24,自引:2,他引:24  
目的分析小梁切除术中应用丝裂霉素C(mitomycin-C,MMC)与青光眼滤过泡相关并发症的关系。方法对31例36只眼在小梁切除术中应用了MMC而导致的滤过泡相关并发症的患眼进行临床分析,分析其滤过泡形态、眼压、视力的改变和黄斑水肿的发生及与术中MMC的浓度、放置时间、放置部位之间的关系。结果31例36只眼中发生滤过泡渗漏11只眼、滤过泡感染1只眼、巨大薄壁滤过泡7只眼、单纯薄壁滤过泡7只眼、低眼压合并黄斑囊样水肿10眼;并发症的发生时间平均(1724±2000)m;平均视力下降2行以上;并发症的发生与MMC放置的位置显著相关,与时间呈正相关,与浓度无关;眼压下降与MMC浓度呈负相关。结论小梁切除术后滤过泡并发症的发生与MMC的应用密切相关,结膜瓣下与巩膜瓣下同时放置、放置时间长者比较容易发生并发症;高浓度者容易造成低眼压。  相似文献   
59.
Yeh JH  Chiu HC 《Journal of neurology》2000,247(7):510-513
Two techniques for plasmapheresis are used in the treatment of myasthenia gravis (MG): immunoadsorption (IA) and double filtration (DR). This controlled study evaluated the differences between these techniques in clinical effects and serological changes. Five patients with generalized MG (clinical states IIb and III) were enrolled; each patient received IA and DF plasmapheresis on separate occasions. Immunosorba TR-350 with an affinity to acetylcholine receptor antibodies (AchRAb) was used for IA, while Evaflux 4A was used as the plasma fractionator for DF. Each course of treatment consisted of five sessions of apheresis. MG score, titers of AchRAb, immunoglobulins (IG), and plasma biochemistry were assessed by blinded examiners before and immediately after the entire course of treatment. Both treatments effectively ameliorated symptoms of MG. There were no significant changes in MG score between the two groups (IA vs. DF: 2.2 vs. 2.6, P>0.5). IA had a higher clearance rate of AchRAb than DF (66 % vs. 54 %, P<0.05), while DF removed more IgA (72 % vs. 21 %, P< 0.05) and IgM (89 % vs. 57 %, P<0.01) than did IA. Although IA removed AchRAb more effectively than DF, the clinical effects between these two treatments were similar. The titers of AchRAb cannot reflect the clinical severity. Some circulating factors other than AchRAb may contribute to the pathogenesis of MG. Received: 10 September 1999, Received in revised form: 7 February 2000, Accepted: 24 February 2000  相似文献   
60.
注射用头孢美唑的无菌检查方法   总被引:1,自引:0,他引:1  
刘贵娟  李黎 《中国药业》2004,13(12):44-44
目的:消除注射用头孢美唑的抑菌作用,以进行无菌检查.方法:用0.9%无菌氯化钠溶液10mL溶解,以薄膜过滤法处理,再用0.9%无菌氯化钠溶液冲洗.结果:加入金黄色葡萄球菌的回收率为76.3%,加入白色念珠菌的回收率为78.2%,供试品的阳性对照成立.结论:该法能消除注射用头孢美唑的抑菌作用,使无菌检查结果准确、可靠.  相似文献   
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