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961.
From January 1986 to December 1988, a prospective trial of transcatheter arterial treatment was carried out for hepatocellular carcinoma (HCC). Two hundred seventy-five patients were included. Okuda's staging system was employed. Patients with Stage I and II HCC were treated by transcatheter arterial embolization (TAE) with a gelatin sponge containing an anti-cancer agent (protocol 1a); a gelatin sponge and iodized oil mixed with an anti-cancer agent (protocol 1b); or iodized oil mixed with an anti-cancer agent (protocol 2). Patients with Stage III HCC were treated with iodized oil with anti-cancer agent (protocol 2). As an exception, patients with an unsuccessful superselective catheterization into the proper hepatic artery by Seldinger technique or obstruction of the main trunk of the portal vein were treated with percutaneous transcatheter arterial infusion into the common hepatic artery regardless of stage (protocol 3). Tumor type and extension, area of tumor involvement, portal vein involvement, method of treatment, and presence of ascites and icterus were found to be the significant factors for an initial response to therapy. Treatment method was the most important factor. Respective survival rates at 1 and 2 years were 70.9% and 55.3% for protocol 1a; 62.3% and 43.8% for protocol 1b; 37.8% and 18.3% for protocol 2; and 16.5% and 0% for protocol 3. Many factors proved to significantly influenced prognosis; however, tumor type had the most important prognostic significance followed by AFP value, ascites, treatment protocol, and area of tumor involvement.  相似文献   
962.
963.
964.
Oxygen withdrawal from myocardial cells leads to changes of the transmembrane action potential (mainly action potential shortening), to cellular uncoupling, and to changes of vascular permeability. This study was aimed at the simultaneous measurement of electrical activity and passive electrical properties (extracellular and intracellular longitudinal resistance) in arterially perfused rabbit papillary muscles under different conditions of changed oxygen supply. These included 1) complete anoxia (erythrocyte-free perfusate), 2) hypoxia (PO2 between 23-28 mm Hg, erythrocytes present) in the presence and absence of glucose, and 3) normoxia with erythrocyte-free perfusate. Similarly to myocardial ischemia, rapid cellular uncoupling occurred only after an initial stable period of approximately 17 minutes, and it required complete anoxia. The marked shortening of the action potential developed before cellular uncoupling. In six out of eight experiments, the fibers were inexcitable when uncoupling started. In severe hypoxia, no significant change of internal longitudinal resistance was observed over 35-40 minutes. The time course of the extracellular longitudinal resistance was different from the change in intracellular resistance: A marked decrease occurred almost immediately after the onset of oxygen withdrawal. This decrease was followed by a small increase in conduction velocity, which was most likely due to a change in the interstitial compartment (edema). It was observed during anoxic as well as during hypoxic perfusion. We conclude that 1) cellular uncoupling in arterially perfused tissue requires almost complete oxygen lack and occurs with a delay of more than 10 minutes, 2) marked action potential shortening precedes uncoupling, and therefore can not simply be attributed to an increase in free, intracellular calcium, and 3) vascular endothelial function is more sensitive to oxygen withdrawal than the myocyte.  相似文献   
965.
The interventional endoscopy and new knowledge about the spontaneous course of the cholelithiasis have obtained a far-reaching influence on the indication for operation and the surgical approach. Now as ever the adequate therapy of the symptomatic cholecystolithiasis consists in the early cholecystectomy. Since in the natural course the risk of lethality is small the operation for indication depending on the age and the risk factors given must be made cautiously. This in a still higher degree concerns the asymptomatic cholelithiasis in which at present no general indication for operation is regarded necessary. Due to the low lethality of circa 1% the endoscopic papillotomy has become the therapeutic method of choice in residual and recurrent calculi after cholecystectomy, but also in risk patients with cholecystocholedocholithiasis. The endoscopic papillotomy with stone extraction before the operation suggests a decrease of the operation lethality of 3 to 5% after cholecystectomy with revision of the choledochus.  相似文献   
966.
As a result of policy changes and developments on the demand side, the importance of technology in primary health care will grow fast. An approach to the implementation of new technologies in primary health care is presented in this article. First we describe the main problems in Dutch primary health care. The second step is to identify new technologies which are becoming available. Subsequently, the interface between these problems and their possible technological resolution has to be found. The fact that a technological innovation appears to be a solution is not sufficient reason for introducing it. There are all kinds of reasons why an innovation that has proved useful in the hospital situation, for example, might be of doubtful use in primary health care. Accordingly, the next step is to assess whether a technological solution to a problem in primary health care is indeed an improvement. To acknowledge the particular situation of primary health care, a scheme has been developed that may be used to determine criteria of evaluation.  相似文献   
967.
Rats were killed after 6 weeks of continuous ingestion of the pneumotoxic alkaloid monocrotaline (2.2 mg/kg/day), the neutrophil elastase inhibitor SC39026 (60 mg/kg/day), or both. Pulmonary reactions were evaluated by light and electron microscopy. Lung endothelial function was monitored by angiotensin converting enzyme (ACE) activity, plasminogen activator (PLA) activity, and prostacyclin (PGI2) and thromboxane (TXA2) production. Lung hydroxyproline content was measured as an index of interstitial fibrosis. Cardiac right ventricular hypertrophy was determined by the right ventricle to the left ventricle plus septum weight ratio (RV/LV + S). Rats receiving SC39026 alone did not differ significantly from untreated control animals with respect to any of the quantitative endpoints, although rarefaction of Type I pneumocytes was observed in the electron micrographs of these animals. Monocrotaline-treated rats, in contrast, developed a significant increase in RV/LV + S, and exhibited pulmonary edema, inflammation, fibrosis, and muscularization and occlusive mural thickening of the pulmonary small arteries and arterioles. These monocrotaline-induced structural changes were accompanied by decreased lung ACE and PLA activities, and increased PGI2 and TXA2 production, and by an increase in lung hydroxyproline content. Cotreatment with SC39026 ameliorated the monocrotaline-induced pulmonary vascular wall thickening and the cardiac right ventricular hypertrophy. These data suggest that inappropriate neutrophil elastase activity contributes to monocrotaline pulmonary vasculopathy and hypertension. On the other hand, cotreatment with SC39026 had no significant effect on the severity of the monocrotaline-induced lung inflammatory reaction, the pulmonary endothelial dysfunction, or the increase in lung hydroxyproline content.  相似文献   
968.
We studied the parathyroid function in patients with advanced renal failure by determining their plasma concentrations of ionized calcium (iCa), intact parathyroid hormone (PTH) and its inactive metabolites (PTH-MM). The suppressibility of the parathyroidism was studied with a calcium infusion test. The intact PTH values of the nondialysis and dialysis patients did not statistically differ from each other. The concentrations of PTH-MM were, however, higher in the dialysis patients than in the nondialysis patients (p less than 0.05). The ratio of PTH-MM to intact PTH was lowest in healthy reference subjects and highest in dialysis patients (p less than 0.01), and did not correlate with the degree of intact PTH elevation in the patient groups. The calcium infusion test was carried out on 15 patients. All showed suppression in the elevated plasma intact PTH concentration and in 6 the intact PTH value normalized. The PTH-MM value did not normalize in any of the patients. During oral calcium treatment the degree of intact PTH suppression at an achieved concentration of plasma iCa was predictable from the infusion test. Three patients were parathyroidectomized after the calcium infusion test. In 2 of these elevated intact PTH normalized within 24 h while in 1 no change took place. In this latter case on clinical improvement was noted. We conclude that the determination of plasma intact PTH concentration especially of combined with plasma iCa value is a reliable means of studying the hyperparathyroidism associated with chronic renal failure.  相似文献   
969.
970.
An attempt was made to explore the quantitative relationship between the intestinal absorption data obtained from in vivo studies and in situ perfusion studies. The time course of the fraction remaining to be absorbed of L-glucose, erythritol, and urea in the small intestine following the intrajejunal administration to rats was described by a one-compartment model. Thus derived first-order intestinal absorption rate constants (ka) obtained from the in vivo studies in rats were compared with the membrane permeability clearances (CLa,m) estimated in a single-pass perfusion system. Not only were ka and CLa,m in the same increasing order of L-glucose less than erythritol less than urea, but also the operational luminal volumes given as CLa,m/ka were in agreement with the in vivo luminal volume of jejunum estimated by an inulin dilution method. This result suggests that the in vivo intestinal absorption rate (or ka) can be correlated with the intestinal membrane permeability (or CLa,m) by taking the in vivo luminal volume into account.  相似文献   
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