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71.
The epoxyalkanoyl derivatives were designed and synthesized as ACE inhibitors. Coupling of unsaturated carboxylic acids with amino acids and following epoxidation with dimethyldioxirane gave the epoxyalkanoyls with high yield. The inhibitory activity of synthesized compounds on angiotensin converting enzyme was IC50 values of 0.06≈5.5 μM.  相似文献   
72.
A 45-year-old man was referred to our department in March of 1989. Physical examination showed erythroderma, palmo-plantar hyperkeratosis, generalized lymphadenopathy, hepatosplenomegaly, and leukemic manifestation. The lymphocyte count in the peripheral blood before treatment was 1.7 × 104 cells/mm3. Atypical lymphocytes such as flower cells and lobulated cells were seen in the peripheral blood. A sample excised from a lymph node showed immunoblastic, pleomorphic T cells by a modified classification scheme of the Working Formulation. A high level of serum LDH was detected (2.1 times the upper normal limit). Anti HTLV-1 antibody was also detected in the serum. The atypical lymphocytes were positive for CD3, CD4, CD5, CD7 and HLA-DR, and negative for CD8. Thus, the clinical, pathologic and immunologic features were those of typical acute-type ATL. The patient was treated with VEPA-M for three months starting in March of 1989. Because of poor response, the patient was then treated with MACOP-B, M-FEPA, and VEPP-B for about one year from June of 1989 and has been free of disease up to the time of writing, March of 1993.  相似文献   
73.
In 44 consecutive patients, 60 porous-coated anatomic total knee (PCA) prostheses with a porous-coated central tibial stem were implanted without using cement. The clinical results and bony remodelling have been assessed after five years' follow-up. The average Hospital for Special Surgery knee score was 33.1 before operation and 95.7 at the latest follow-up, while the average range of movement improved from 63 degrees to 123 degrees. No subsidence or migration of the components was seen. A radiodense line appeared around the components at six months to one year after the operation and became more dense with time. There was no evidence of bone resorption related to stress-shielding in the tibial plateau.  相似文献   
74.
Study Objective . To compare the frequency, severity, and time course of venous irritation after administration of a single intravenous dose of phenytoin with an equimolar dose of fosphenytoin, a water-soluble phenytoin prodrug. Design . Randomized, double-blind, two-period, crossover study. Setting . University hospital clinical research unit. Patients . Twelve healthy volunteers within 15% of ideal body weight and with no clinically significant abnormalities on physical examination, medical history, or laboratory assessment. Interventions . Volunteers randomly received a 30-minute infusion of phenytoin sodium 250 mg (250 mg/5 ml) or an equimolar dose of fosphenytoin 375 mg (375 mg/5 ml). Subjects returned for the crossover treatment 14–21 days later. Measurements and Main Results . Subjects assessed venous irritation (pain, burning, itching), and investigators evaluated phlebitis (erythema, swelling, tenderness), induration, exudation, and cording. Phenytoin was associated with a significantly higher degree of pain at the infusion site in all subjects and a significant degree of phlebitis in eight subjects (p<0.05); cording occurred in six subjects. The time course of phenytoin-induced phlebitis was bimodal. Erythema and tenderness were prominent at the end of the infusion and again at 24 hours. Cording was first noted between 24 hours and 1 week after infusion. In contrast, fosphenytoin was associated with mild pain in two subjects, one incident of phlebitis, and no erythema or cording. Conclusions . Fosphenytoin administration resulted in significantly less venous irritation and phlebitis compared with an equimolar dose of phenytoin. The clinical use of this water-soluble phenytoin prodrug should minimize the frequency and severity of infusion-site reactions and should allow convenient, rapid, intravenous administration of drug, undiluted or admixed with intravenous solutions.  相似文献   
75.
A regioselective preparation of 10-methoxy-11-hydroxyaporphine (“Apocodeine,1b”) from (R,S)-10, 11-dihydroxyaporphine(apomorphine,1a) is described. The isopropylidene ketal ring of 10,11-(isopropylidenyldioxy) aporphine (2) obtained by the isopropylidenation of apomorphine, was regioselectively opened by the ten equivalent of trimethylaluminum to give 10-hydroxy-11-t-butyloxyaporphine (3). The free 10-hydroxyl position of 3 was methylated with methyl p-toluenesulfonate/NaH, and afforded 10-methoxy-11-t-butyloxyaporphine (4) in high yield. Selective debutylation gave the desired 10-methoxy-11-hydroxyaporphine (“apocodeine”,1b) in good yield.  相似文献   
76.
From January 1986 to December 1991 we examined the eyes of 206 infants born at Westmead Hospital, Neonatal Intensive Care Unit who were less than 29 weeks' gestation at birth to determine the incidence of retinopathy of prematurity. Eighty-five infants (41.3%) had no retinopathy of prematurity (ROP) in either eye, 82 infants had stages 1 or 2 ROP (39.8%), 29 had stage 3 ROP (14.1%) and 11 had stage 4 ROP (5.3%). Of these, cryotherapy was performed in 18; six now have bilateral retinal detachment and are blind The more severe stages of ROP were significantly associated with an increase in the number of days of oxygen supplementation, an increase in the number of days of mechanical ventilation and the presence of patent ductus arteriosus. Infants receiving steroids for mechanical ventilator dependence had a significantly greater chance of requiring cryotherapy (11 or 22 receiving steroids versus seven of 43 without steroids; P < 0.01).  相似文献   
77.
The classical from of Wegener's granulomatosis (WG) is a necrotizing granulomatous angiitis that involves the upper and lower airways, and kidneys. A limited form of WG is characterized by pulmonary lesions identical to those of classical form WG without renal involvement. The authors report a case of limited form WG. A 58-year-old Japanese woman was admitted because of an abnormal pulmonary shadow. Pathological examination revealed granulomatous angiitis consistent with WG. No other organ involvement was found. The pulmonary shadow improved with cyclophosphamide therapy. The patient is now well and without evidence of exacerbation of the disease 18 month after the discharge.  相似文献   
78.
Subacute (daily) administration of diisopropylfluorophosphate (DFP) to male swine (Yorkshire white) resulted in a 97% inhibition of cholinesterase and a decrease of [3H]quinuclidinyl benzilate [( 3H]QNB) binding sites in homogenates of striata by approximately 50% after 14 days. The maximal density of receptors (Bmax) decreased from 2.1 +/- 0.3 to 1.0 +/- 0.2 pmole/mg protein. There was no significant change in the dissociation constant (Kd) for [3H]QNB binding (control: 52.6 +/- 10.7 pM; 7-day: 57 +/- 2.8 pM). Carbachol displacement of [3H]QNB binding yielded data best fit by a two-binding site model. The dissociation constants were KiL = 115 +/- 62 microM (55 +/- 3%) and KiH = 1.8 +/- 0.7 microM (45 +/- 3%), respectively, for the low- and high-affinity states. Seven-Day treatment with DFP reduced the percentage of high-affinity receptors to 22 +/- 8.6%, but affected neither the low- nor the high-affinity Kd (100 +/- 20 and 2 +/- 0.6 microM). With the addition of Mg2+, striatal homogenates had low- and high-affinity receptors in the proportion of approximately 1 to 1. In the presence of Gpp(NH)p + Mg2+ the ratio of high- to low-affinity receptors was 3:1 in homogenates of control tissue (to 26 +/- 5%). This treatment had no effect on this ratio in homogenates of tissue from 7-day DFP-treated swine (3:1) since it was already 3:1. Pirenzepine displacement of [3H]QNB binding was best described by a two-binding site model, with Ki values of 38 +/- 14 and 201 +/- 78 nM, which represent 74 and 26% of the binding sites, respectively. The high affinity Kd value was unchanged following 7 days of DFP treatment (24 +/- 5 nM). There appears to be little change in the displacement curves for pirenzepine inhibition of [3H]QNB binding. This suggests that about 75% of the receptors are of the M1 subtype. Thus, subacute administration of DFP causes not only a decrease in the number of receptors, but also a change in the proportion of agonist affinity states which is related to the interaction of the guanine nucleotide binding protein and the muscarinic receptor.  相似文献   
79.
S Y Kim  N L Benowitz 《Drug safety》1990,5(6):393-420
Quinidine, procainamide and disopyramide are antiarrhythmic drugs in the class 1A category. These drugs have a low toxic to therapeutic ratio, and their use is associated with a number of serious adverse effects during long term therapy and life-threatening sequelae following acute overdose. Class 1A agents inhibit the fast inward sodium current and decrease the maximum rate of rise and amplitude of the cardiac action potential. Prolonged Q-T interval and, to a lesser extent, QRS duration may be observed at therapeutic concentrations of quinidine. With increasing plasma concentrations, progressive depression of automaticity and conduction velocity occur. 'Quinidine syncope' (a transient loss of consciousness due to paroxysmal ventricular tachycardia, frequently of the torsade de pointes type) occurs with therapeutic dosing, often in the first few days of therapy. Extracardiac adverse effects of quinidine include potentially intolerable gastrointestinal effects and hypersensitivity reactions such as fever, rash, blood dyscrasias and hepatitis. Procainamide produces electrophysiological changes that are similar to those of quinidine, although Q-T interval prolongation with the former is less pronounced at therapeutic concentrations. Hypersensitivity reactions including fever, rash and (more seriously) agranulocytosis are associated with procainamide, and a frequent adverse effect requiring cessation of therapy is the development of systemic lupus erythematosus. Of the 3 drugs, disopyramide has the most pronounced negative inotropic effects, which are especially significant in patients with pre-existing left ventricular dysfunction. As with quinidine, unexpected 'disopyramide syncope' at therapeutic concentrations has been described. Anticholinergic side effects are common with this drug and may require cessation of therapy. Disopyramide therapy may unpredictably induce severe hypoglycaemia. Severe intoxication with the class 1A agents may result from acute accidental or intentional overdose, or from accumulation of the drugs during long term therapy. Acute overdose can result in severe disturbances of cardiac conduction and hypotension, frequently accompanied by central nervous system toxicity. Decreased renal function can cause significant accumulation of procainamide and its active metabolite acecainide (N-acetyl-procainamide), resulting in severe intoxication. Mild to moderate renal dysfunction is less likely to lead to quinidine or disopyramide intoxication, unless renal failure is severe or concurrent hepatic dysfunction is present. Management of acute intoxication with class 1A drugs includes gut decontamination with provision of respiratory support and treatment of seizures as needed. Hypertonic sodium bicarbonate, by antagonising the inhibitory effect of quinidine on sodium conductance, may reverse many or all manifestations of cardiovascular toxicity.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
80.
Chondroitin sulfates were isolated from the mud snail. For the quantitative analysis of enzymatic digestion products of isolated chondroitin sulfates, strong anion exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action of chondroitinase ABC, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-D-galactose (ΔDi-OS), 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose (ΔDi-6S) and 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose (ΔDi-4S) were produced from the mud snail chondroitin sulfates. The analysis showed that relative proportion of ΔDi-OS/ΔDi-6S/ΔDi-4S was 58.7/3.1/38.2. The immunomodulating activity of chondroitin sulfate was examined by cell proliferation assay and these results suggest that it might be a immunosuppressant.  相似文献   
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