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21.
The radiologic and histologic findings are presented of the resection of 14 small hepatocellular carcinomas (HCC), less than 2 cm in maximum diameter, after transcatheter arterial chemoembolization (TCE) using iodized oil. The effect of TCE on small HCC depended on the morphologic type of the tumors. When no extracapsular invasion of tumor cells occurred, TCE was extremely effective against encapsulated tumors. However, in nine of the 14 resected specimens, viable tumor cells remained in or around the tumor. The authors suggest that small HCC are not always curable with TCE alone and that a multi-disciplinary approach is necessary for patients with small HCC.  相似文献   
22.
A case of severe right radicular ischias following embolization is reported. Gelfoam powder and pledgets were used for right internal iliac artery embolization in the case of intractable bladder cancer hemorrhage. It is supposed that previous radiotherapy and fine embolic material may be the contributing factors to this complication.  相似文献   
23.
1. The present study was undertaken to examine whether or not 5-HT-induced inositol monophosphate (IP-1) accumulation in human platelets is mediated by 5-HT-2 receptors and to assess 5-HT-2 receptor function as measured by 5-HT-stimulated IP-1 accumulation in platelets from normal controls and depressed patients before drug treatment. 2. In platelets prelabeled with 3H-myo-inositol, in Ca ion free HEPES buffer containing 10 mM LiCl, 5-HT caused a dose-dependent accumulation of IP-1 during 15 min incubation. A maximal increase in IP-1 formation was observed at 30 microM of 5-HT and its EC50 value was 4 microM. 3. Ketanserin, a selective 5-HT-2 antagonist, was a potent inhibitor of 5-HT-stimulated IP-1 accumulation with a Ki value of 12 nM, but (-)propranolol (10 microM), a 5-HT-1 antagonist, failed to block the 5-HT response. 4. The potencies of various compounds tested to inhibit 5-HT-stimulated IP-1 accumulation in human platelets correlated positively with the affinities to 5-HT-2 receptor as defined by radioligand binding in rat cerebral cortex. 5. In a group of unmedicated patients with major depressive disorder matched for age with normal control group, we found a significant increase in 5-HT (100 microM)-induced accumulation of IP-1 (150 +/- 7% of basal for depressed patients, 132 +/- 3% for controls).  相似文献   
24.
Summary Haemorrhage in regions remote from the site of following intracranial operations is rare, but they do occur. We performed supratentorial craniotomy on 639 patients between the time of introduction of computed tomography (CT) for clinical use in 1983 and June 1992; subarachnoid haemorrhage (SAH) in the posterior fossa occurred postoperatively in six of these cases. These included four patients with tumours in the sellar region, one with an arteriovenous malformation (AVM) and one who underwent superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis. The ages of the six patients ranged from 17–72 years.Haemorrhage occurred on the day of operation in one case and was detected on CT examination on the day following surgery in the remaining five cases. Of three patients with disturbance of consciousness, two underwent suboccipital craniectomy for reduction of intracranial pressure, while one received barbiturate therapy and later underwent cerebrospinal fluid (CSF) shunt surgery. No special treatment was necessary for the remaining three patients with less serious lesions. Five of the six patients ultimately recovered their pre-operative neurological status apart from the primary diseases.Factors inducing such haemorrhages seem likely to include displacement of the cerebellum by reduced CSF pressure during and after operations, and stretching and tearing of the veins and venules in the sulci of the tentorial surface of the cerebellum. Consideration should therefore be given to the maintenance of an appropriate CSF pressure during operation; this is particularly important in elderly patients and those with an atrophied cerebral cortex.  相似文献   
25.
Background :
The BTA test is a latex agglutination assay for the qualitative detection in the urine of analytes that are associated with bladder tumor. We compared the results of the BTA test with those of voided urine cytology (VUC) in patients with bladder cancer.
Methods :
A multicenter trial was performed at 6 institutions. A total of 132 patients with histologically diagnosed bladder cancer were enrolled. Urine samples were split for BTA and VUC testing.
Results :
The sensitivities of the BTA test and VUC were 57.6% and 37.9%, respectively; this difference was significant ( P < 0.001). The BTA test had much higher sensitivity for small, solitary, superficial tumors than did VUC.
Conclusion :
The BTA test is simple to perform, gives rapid results, and is far more sensitive than VUC for detection of bladder cancer. The BTA test has the potential to become an additional tool for detecting bladder cancer.  相似文献   
26.
Benazepril (CGS 14824A HCl) is a new prodrug type angiotensin converting enzyme (ACE) inhibitor. The active form is considered to be benazeprilat, a diacid hydrolyzed compound. Benazepril and benazeprilat inhibited the contraction induced by exposure with angiotensin I, not angiotensin II, in the isolated rabbit aorta. The ACE inhibiting activity of benazeprilat was 1000 times more potent than that of benazepril in this experiment. Benazepril as well as benazeprilat and captopril exerted little influence on norepinephrine, serotonin and high K(+)-induced contraction or bradykinin-induced relaxation in isolated blood vessel preparations, thus angiotensin II synthesis inhibition seemed to be the main cause for its vasodilation. Benazepril, unlike benazeprilat or captopril showed considerable influence on prostaglandin (PG)-induced responses at higher concentrations. The vasocontraction induced by PGF2 alpha was competitively antagonized at 10(-5)-10(-4) mol/l, while vascular responses induced by PGE1, PGE2 or PGI2 was inhibited at 3 x 10(-4) mol/l of benazepril. Although these influences on PGs might not contribute much to its vasodilatory mechanism, the action seemed interesting in relation to cough induction, a known side effect of ACE inhibitors in the market. Benazepril has two asymmetric carbon atoms, thus four optical isomers are possible, SS (benazepril), SR (CGP 14'829A), RS (CGP 42'454A), RR (CGP 42'456A). The SS configuration was the most potent for antagonizing angiotensin I-induced vasocontraction, which seemed to be the best fitted for the ACE molecule.  相似文献   
27.
Referenceless, or self-reference, thermometry is a technique for mapping temperature differences in the region of interest (ROI) using the baseline phase estimated by extrapolating the field in the surrounding region for estimation (RFE) and subtracting the estimated baseline from the measured field. In the present work a self-reference technique based on complex field estimation using 2D polynomials comprising complex-valued coefficients was proposed and optimized. Numerical simulations with a Gaussian-profiled phase distribution demonstrated that the ROI radius had to be 2.3-2.5 times the standard deviation (SD) of the Gaussian function in order to keep the error below 8% of the peak phase change. The area ratio between the ROI and the RFE had to be larger than 2.0 to maintain the error level. Based on the simulations, and phantom and volunteer experiments, the complex-based method with independently optimized polynomial orders for the two spatial dimensions was compared with the phase-based method using the similar-order optimization strategy. The complex-based method appeared to be useful when phase unwrapping was not removed. Otherwise, the phase-based method yielded equivalent results with less polynomial orders.  相似文献   
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