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71.
Secondary extradural spinal tumours are very rare, but they comprise most of the extradural neoplasms seen in infancy and childhood. Thirty-nine patients with this type of secondary tumour were treated in our hospital between 1965 and 1991. The diagnosis was proved by biopsy in every case. Following surgical decompression, all 35 survivors had radiotherapy and/or chemotherapy. Their outcome is reported.  相似文献   
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When stimulating the peripheral and of the right n. vagus in anesthetised cats, the sinus arrhythmia occurred in case the vagal bursts were beyond the limits of the controlled bradycardia range. I. v. administration of met-enkephaline suppressed the arrhythmia immediately but the latter reappeared within 15-20 minutes. The data obtained suggests a biphasic effect of met-enkephaline upon the vagal sinus arrhythmia.  相似文献   
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The aims of the study were to compare the value of L-[1-11C]tyrosine (TYR) and [IBF]fluoro-2-deoxy-D-glucose (FDG) as tumor tracers in patients with breast cancer, to investigate the correlation between quantitative values and standardized uptake values (SUVs) and to estimate the value of SUVs for the evaluation of therapy. METHODS: Eleven patients with one or more malignant breast lesions and two patients with one or more benign breast tumors were studied with TYR and FDG. Doses of 300 MBq of TYR and 230 MBq of FDG were given intravenously. All PET sessions were performed using a Siemens ECAT 951/31 camera. Of 10 malignant tumors and the 3 benign lesions, glucose consumption and protein synthesis rate were quantified. All lesions were studied using SUVs based on body weight, body surface area and lean body mass, with and without correction for plasma glucose or tyrosine levels. RESULTS: All malignant tumors were visualized with both FDG and TYR, but the visual contrast was better with FDG. Increased uptake of the tracers was seen in patients with fibrocystic tissue and complicated the visual assessment and the outlining of tumor tissue. Uptake in fibrocystic disease was more prominent with FDG than with TYR. No difference in tumor/nontumor ratio between the two tracers could be established. FDG showed a false-positive result in one benign lesion. No major differences between the SUVs as defined above were found, although the best correlation between glucose consumption and the SUV was observed when the SUV was based on body surface area and corrected for plasma glucose level (r = 0.85-0.87). The SUV based on lean body mass was found to correlate best with protein synthesis rate (r = 0.83-0.94). CONCLUSION: In this group of patients, TYR appears to be a better tracer than FDG for breast cancer imaging, because of lower uptake in fibrocystic disease. SUVs correlate well with quantitative values, but future studies must determine whether treatment evaluation is also reliable with SUVs.  相似文献   
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In end-stage heart failure, cardiac beta-adrenoceptors are decreased and cardiac Gi protein is increased. We assessed beta-adrenoceptors, G proteins, and effects of several beta-adrenoceptor agonists, histamine, and 5-HT on adenylyl cyclase activity in right and left atria and left ventricles and on left ventricular contractility in six potential heart transplant donors (nonfailing hearts; NFHs) and in nine patients with end-stage dilated cardiomyopathy (DCM) and 11 patients with end-stage ischemic cardiomyopathy (ICM) to establish whether the functional responsiveness of all cardiac Gs-coupled receptors is reduced. Beta-adrenoceptors were reduced in all three tissues; in DCM, beta1-adrenoceptors were more markedly downregulated; in ICM, both beta1- and beta2-adrenoceptors were diminished. In all three tissues, isoprenaline-, terbutaline-, histamine- and 5-HT-induced adenylyl cyclase activation was reduced similarly in DCM and ICM. Moreover, in DCM and ICM, guanosine triphosphate (GTP)- (involving Gs and Gi) activated adenylyl cyclase was significantly diminished, whereas NaF-activated (involving only Gs) and Mn2+-activated (acting at the catalytic unit of the enzyme) adenylyl cyclase was unaltered. Left ventricular positive inotropic responses to beta1- (noradrenaline, dopamine, and dobutamine), beta2- (terbutaline), and beta1- and beta2-adrenoceptors (isoprenaline, adrenaline, and epinine), as well as H2-receptor (histamine) stimulation were significantly reduced. The extent of reduction was not different for each agonist in ICM and DCM. We conclude that in DCM and ICM, functional responsiveness of all cardiac Gs-coupled receptors is similarly reduced.  相似文献   
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Negative prejudices against psychiatry and psychiatric patients are a reality today. But prejudices are also existent in the patients self, especially in schizophrenic patients, leading to adverse therapeutic reactions. Prejudices of the patients himself may be a hidden, unconscious problem in some cases of treatment resistance in rehabilitation of schizophrenic patients. Therapeutic strategies are discussed on the basis of case reports.  相似文献   
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We describe a distinctive tissue artifact that results from the use of biopsy bags for processing small impressionable pieces of tissue. In its fully developed form, the artifact produces a tic-tac-toe pattern, while in less pronounced cases it may produce elongated oval spaces in the tissue or a serrated contour at the periphery of the tissue. The artifact was observed in 60% of endometrial specimens, 55% of endocervical curettings, and sporadically in other small specimens. In the endometrial and endocervical specimens, the artifact was focal and did not interfere with the diagnosis. In occasional small lung and prostate specimens, there was focally significant distortion that potentially could compromise the diagnosis.  相似文献   
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