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991.
992.
993.
The presented report is fibrosarcoma arising from renal capsule in a 64-year-old woman. The tumor is very rare and is the 25th case in Japan. The patient visited our hospital with the complaint of macroscopic hematuria for several days. Abdominal examination revealed a painless lump from the left lumbar region to para-median abdomen. A diagnosis of hydronephrosis caused by neoplasma or tuberculosis was considered by CT, AG, etc., and transperitoneal nephrectomy was performed on 6-July-1984. Pathology of the tumor was fibrosarcoma arising from the renal capsule. Three months later, the tumor was growing on the peritoneal surface from the left renal region and she died on Nov. 10, 1984.  相似文献   
994.
Priapism: a refined approach to diagnosis and treatment   总被引:4,自引:0,他引:4  
The recent introduction of intracorporeal injections of papaverine and phentolamine for the diagnosis and treatment of impotence has resulted in an increased incidence of iatrogenic priapism. Based on our research into penile hemodynamics we propose a refined approach to all types of priapism. Intracorporeal blood gas and pressure monitoring should be used to differentiate ischemic (low flow) from nonischemic (high flow) types. Most cases of papaverine-induced or phentolamine-induced priapism will respond to aspiration alone or in combination with intracorporeal instillation of a diluted alpha-adrenergic agent. In spontaneous priapism alpha-adrenergic agents can be tried first if patients have only mild or no ischemia. In patients with severe ischemia stagnant blood should be evacuated and a shunt procedure should be performed to allow metabolic replenishment of tissue. Intracorporeal pressure monitoring will help to determine the size and number of shunts needed to re-establish corporeal circulation.  相似文献   
995.
The technique and use of a percutaneous subclavian vein catheter for haemodialysis in 20 patients are reported. The catheterization procedure carried a very low morbidity, and blood flow rates of 200–250ml/min were achieved through the catheters. Use of this angioaccess saves future possible sites for permanent vascular access. Infectious complications were not encountered. Subclavian vein catheterization is a favourable alternative to external Silastic Teflon shunt.  相似文献   
996.
Surgery of Dupuytren's disease: a review of the open palm method   总被引:1,自引:0,他引:1  
Experience with 49 cases of Dupuytren's disease treated by the open palm method and followed for an average of 5 years is reported. This method permits excision of the involved fascia while minimizing early postoperative morbidity associated with the surgical management of this condition. There were no cases of wound necrosis, hematoma, or infection with this technique, and all wounds closed spontaneously within 3 to 5 weeks. Long-term follow-up, however, revealed a significant rate of recurrence (32%) and extension (48%), as well as flexion loss at one or more joints in 41% of involved hands. While helpful in the early care of these patients, the open palm method does not modify the long-term results in Dupuytren's disease, which is a pervasive condition without simple surgical solution.  相似文献   
997.
The effects of methyl 2,6-dimethyl-4-(2-nitrophenyl)-5-(2-oxo-1,3,2-dioxaphosphorinan-2- yl)-1,4- dihydropyridine 3-carboxylate (DHP-218), a new dihydropyridine calcium antagonist, on vascular smooth muscles, cardiac muscles and [3H]-nitrendipine binding to the cardiac muscle and brain membranes were investigated in vitro. Vascular smooth muscles: Calcium-induced contraction of the rat aorta in high K+ solution was inhibited by DHP-218 with the pA2 value of 9.11. The IC50 value for the inhibitory effects of this compound in high K+-induced and phenylephrine-induced contraction was 6.3 nmol/l and 66 nmol/l, respectively. Vasodilatory effects of this drug on various blood vessels of rabbits contracted by high K+ appeared to a similar extent. The onset of the vasodilatory effect was very slow and the recovery rate of vasodilatory response after washout with the bathing solution containing high K+ or phenylephrine was also very slow. Cardiac muscles: Negative chronotropic and inotropic actions were observed at concentrations more than 30 and 100 nmol/l, respectively. Duration of the plateau phase of normal action potential was shortened and the amplitude and duration of slow action potential were reduced at concentrations more than 1 mumol/l. Very high vasculoselectivity was observed. Displacement of [3H]-nitrendipine binding: The pattern of displacement of [3H]-nitrendipine binding by DHP-218 was very similar to that of other 1,4-dihydropyridines but this compound was about 70 times less potent than nifedipine in [3H]-nitrendipine displacement capacity. These results indicate that DHP-218 has specific vasodilatory action due to calcium antagonism, but association and dissociation rates with tissue and receptors were different from those of nifedipine.  相似文献   
998.
999.
Four enantiomers (3a-d) of the title compound, YM-09730 (3), were synthesized by the reaction of (-)- or (+)-5-(methoxycarbonyl)-2, 6-dimethyl-4-(m-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid (1a or 1b) with (S)- or (R)-1-benzyl-3-pyrrolidinol (2a or 2b). [3H]Nitrendipine binding affinity and coronary vasodilating activity of these compounds were evaluated. The absolute configuration of the most potent enantiomer (3a) with the longest duration was unequivocally determined to be (S)-1,4-dihydropyridine-C4 and (S)-pyrrolidine-C3 (S,S) by X-ray crystallographic study on 3a X HBr as well as 3a X HCl. The configuration of 1a corresponds to R, and the other enantiomers of 3 were respectively determined by chemical correlation. The potency order of the four enantiomers was (S,S)-3a greater than (S,R)-3b greater than (R,R)-3d greater than (R,S)-3c. Latent chiral characters of nifedipine derivatives with the identical ester groups were assigned by comparison of their puckering modes of 1,4-dihydropyridine (DHP) rings with those found in 3a X HCl or 3a X HBr. On the basis of the assignment, it has been revealed that the (S)-DHP nifedipine derivatives possess the synperiplanar carbonyl group at C5. The conformational restriction may be a factor causing stereoselectivity of antagonism.  相似文献   
1000.
The interaction of an organic acid with sodium bicarbonate in water produces an effervescent reaction. The reaction products are carbon dioxide, water, and the sodium salt of the acid. The kinetic rate-determining step for this reaction is the dehydration of carbonic acid. The solid-solid interaction with known amounts of moisture was followed by quantitatively determining carbon dioxide evolution as a function of time. The aqueous solubilities, diffusion coefficients, dissociation constants, and solid-solid interaction rates of six different substituted benzoic acids were determined. Using a model based on diffusion of the organic acid through the aqueous layer coupled with chemical reaction, predicted rates and levels of carbon dioxide production were compared with experimental results. Included in the model were the effects of the reaction products on the solution properties of the reactants. It was found that high concentrations of substituted sodium benzoate were generated very quickly and affected the solubility of the reactants, diffusion coefficient of the acid, and the carbonic acid dehydration rate constant. Moisture content was found to have a profound influence on the interaction rate. Water provides a medium for diffusion of the reacting species as well as the reaction solvent.  相似文献   
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