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91.
ABSTRACT

The activities of angiotensin converting enzyme(ACE) in crude extracts of renal cortex, heart and brain of the rat were increased when the oxidizing agent diamide was added to the extracts and then the activity determined. By pretreatment of the extracts with 10 mM diamide, the activities of ACE in the extracts of heart, brain and renal cortex were about 500, 290 and 240 % of the control value, determined without the diamide-pretreatment, respectively. In the lung and aorta, increments in the activity after oxidation were less than 20 % of the control. No such increase was observed in the plasma. Similar results were obtained when the extracts were exposed to O2. The activity was also increased by oxidation with diamide and O2, when an extract of the human renal cortex was used. Thus, the activity of ACE in the kidney, heart and brain can be increased by oxidation.  相似文献   
92.
Captopril, given for 5 days to normotensive healthy subjects caused a significant fall in blood pressure. The fall in mean supine blood pressure was greater on a low sodium diet (10 mmols/ day) - 19.6% and was less on a high sodium diet (350 mmols/day) - 11% compared to the normal sodium intake (120 mmols/day) when the fall in blood pressure was 16.5%. Patients with essential hypertension who were studied on their normal diet had a similar fall in blood pressure for a given plasma renin activity. It seems likely that the predominant mechanism whereby captopril lowers blood pressure is through the inhibition of the formation of angiotensin II. If this is so, our results suggest that the renin system is an important control of both normal and high blood pressure when on a normal sodium intake.  相似文献   
93.
CGS 35601 is a triple vasopeptidase inhibitor (VPI) of angiotensin-converting enzyme, neutral endopeptidase, and endothelin-converting enzyme-1 with respective IC50 values of 22, 2, and 55 nM. We characterized the safety profile and toxicity of escalading doses of CGS 35601 over a 20-day period in chronically instrumented, unrestrained, conscious, male, spontaneously hypertensive rats (SHR). Once instrumented with an arterial catheter, the SHR were placed in metabolic cages allowing daily assessment of hemodynamics and blood sampling for biochemical and hematological measurements. After a 7-day stabilization period, the SHR were divided into 2 groups: Gr. 1, (n = 13 to 18) receiving CGS 35601 at 0.01, 0.1, 1 and 5 mg kg?1 day?1 (continuous i.a. infusion) for 5 consecutive days/dose, followed by a 5-day washout; and Gr. 2, (n = 10) receiving vehicle (saline). The highest dose of CGS 35601 dose-dependently reduced MABP from 156 ± 4 up to 94 ± 5 mm Hg, whereas heart rate, metabolic, electrolytic, and hematological profiles, growth, diuresis, and renal activity were unaffected, and no hepatic or liver toxicities were observed. These results suggest that this novel triple VPI presents no safety concerns at this stage and may become of interest for the treatment of hypertension and other cardiovascular disorders. Long-term chronic experiments are needed to assess possible angioedema and increases in vascular permeability.  相似文献   
94.
Before the computer can become truly useful in clinical research, diagnosis and therapy, new ways to collect data must be developed. The computer itself can be adapted to take medical histories directly from patients. These data, in computer- processable form, are then available for physician use in patient care and clinical research. Results obtained with computer-based histories are reviewed and the technic is compared with traditional methods. Also discussed is the potential role of computer-based interviewing in modern medical practice.  相似文献   
95.
This section is reserved for commentaries and brief essays dealing with matters of interest to physicians. Material for consideration should not exceed Ave double-spaced typewritten pages. An honorarium of $75 is offered at the time of publication. Submissions should be addressed to: Editor, POSTGRADUATE MEDICINE, 4530 W 77th St, Minneapolis, MN 55435.  相似文献   
96.
A simple amidolytic method for the determination of the concentration of functionally active antithrombin III is described. Plasma is diluted with buffer containing EDTA and Polybrene®. In stage I, diluted plasma is incubated with thrombin. EDTA retards fibrin polymerization, and plasma fibrinogen does not influence the assay. Polybrene makes the assay result independent of heparin. In stage II, remaining thrombin is determined with the chromogenic substrate benzoyl-Phe-Arg-p-NA. The method is simpler and has a higher accuracy than clotting methods. There is a close correlation between the results obtained with this assay and with immunoassay of antithrombin III.  相似文献   
97.
Oral feeding of trypsin inhibitor is known to stimulate rat pancreatic enzyme secretion and cause hypertrophy of the pancreas. In an attempt to detect a possible serum factor(s) responsible, the effects of serum from trypsin inhibitor fed rats on enzyme secretion and protein synthesis by isolated exocrine rat pancreatic cells in suspension were studied.

Serum from trypsin inhibitor fed rats stimulated the secretion of pancreatic enzymes significantly more than serum from control rats. The data suggest that a humoral factor or factors may be involved in the stimulation of pancreatic enzyme secretion by oral trypsin inhibitor.

Serum from trypsin inhibitor fed rats as well as serum from control rats stimulated the 3H-leucine incorporation into protein (protein synthesis) to a significant extent. There was, however, no difference in the effects of the two types of sera in this respect.  相似文献   
98.
99.
Background: Fabry disease is an X-linked lysosomal storage disease caused by deficiency of α-galactosidase A (α-Gal A), encoded by the GLA gene. The deficiency causes accumulation of neutral glycosphingolipids in various tissues, leading to neuronopathic pain, progressive renal dysfunction, cardiomyopathy and stroke. Enzyme replacement therapy (ERT) with agalsidase alfa (Replagal?, Shire Human Genetic Therapies) is approved for use by 40 countries, but not the US. Objective: To evaluate agalsidase alfa in therapy of Fabry disease. Methods: An examination of relevant reports. Results/Conclusions: Clinical trials data, along with experience of the treatment collected through participation of treating physicians in a world-wide Fabry disease registry, have demonstrated that it improves pain and stabilizes renal function, as well as cardiomyopathy, in some patients. More data are needed to evaluate the role of treatment with this drug in the prevention of stroke and adverse cardiac events, and its overall effect on the lifespan and quality of life of affected individuals.  相似文献   
100.
目的探讨延长不同实验步骤温育时间对乙肝表面抗原(hepatitis B surface antigen,HBs Ag)酶联免疫吸附实验(enzyme-linked immunosorbent assay,ELISA)结果的影响,从而保证检测结果的准确性和精确性。方法在其他实验参数不变的条件下,通过延长加酶前、加酶后、显色等步骤的温育时间,分别对强阳性、中阳性、弱阳性、阴性标本进行检测,所得数据采用SPSS 17.0软件进行相关分析。结果 1延长加酶前温育时间对强阳性和弱阳性标本的影响差异具有统计学意义,强阳性标本吸光度明显下降,弱阳性标本明显加强,并与延长的时间密切相关。2延长加酶后温育时间对各标本吸光度(阴性除外)影响最显著。3延长显色时间对实验结果影响并不明显。4延长各反应步骤温育时间对HBs Ag阴性标本吸光度影响均无统计学意义。结论选择正确的步骤适当延长温育时间可提高ELISA实验结果的准确性和弱阳性标本的检出率。  相似文献   
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