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21.
Neurosurgical Review - Chordoma is a rare slow-growing neoplastic bone lesion. However, they show an invasive local growth and high recurrence rate, leading to an overall survival rate of 65% at 5...  相似文献   
22.
Studies comparing urinary norepinephrine (NE) and its metabolites in unipolar or bipolar depressed patients and healthy volunteers have not yielded consistent findings. However, in unipolar depressed patients, most studies in non-elderly populations consistently report elevated concentrations of plasma NE, at least following an orthostatic challenge. Expanding upon previous studies which showed elevated plasma NE in depression, we compared the urinary excretion of NE, normetanephrine (NMN), 3-methoxy-4-hydroxyphenylglycol (MHPG), and vanillylmandelic acid (VMA) in age- and sex-matched unipolar and bipolar depressed patients versus healthy volunteers hospitalized at an inpatient unit at the National Institute of Mental Health. Only depressed subjects with a minimum 4-week drug-free period were included. Total turnover (NE + NMN + MHPG + VMA) was reduced in this sample of unipolar and bipolar depressed patients. MHPG concentration did not distinguish unipolar from bipolar depressed patients and was not significantly different from that in healthy volunteers. A construct of the average fractional extraneuronal concentration of NE (NE + NMN/NE + NMN + MHPG + VMA) was significantly higher in unipolar and bipolar depressed patients than in healthy volunteers. This finding extends data suggesting that unmedicated unipolar and bipolar depressed patients have a 'hyperresponsive' noradrenergic system and provides a framework which ties together plasma and urinary findings.  相似文献   
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Aim of this work is to show the results of the evaluation of the sensitometric properties of a new Du Pont anti cross-over radiographic film system called Ultra Vision, based on a new film and different YTaO4 undoped screens whose emission is centered at about 335 nm. Fog, contrast, latitude, sensitivity, noise and resolution were tested: the MTFs were obtained by exposing a standard resolution pattern and using the "zero"-frequency step as a knife edge. The image of this knife edge was scanned with a microdensitometer with a 20 microns slit. The results (at 70 kVp with 2.5 mm Al and 2.5 mm Cu total filtration), compared with those of Du Pont conventional radiographic screen-film systems Cronex 10 S/Quanta, show that the new system significantly increases contrast, sensitivity and resolution and will consequently improve, in the clinical use, radiographic image quality.  相似文献   
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Spontaneous portosystemic shunts are commonly found in cirrhotic patients. Not yet established is their role after orthotopic liver transplantation (OLTx), especially when an increase in portal pressure develops, as during early acute rejection. In this study, 34 cirrhotic patients in a series of 70 OLTx are considered. Each patient had preoperative angiographic assessment, and, in 21 (62%), large spontaneous portosystemic shunts were evident. In 12 cases the shunts were not affected by the surgical procedure and were present during the postoperative period; in 9 the hepatectomy itself involved interruption of the shunts. The patient population was divided into two groups: patients with postoperative shunts (n=12) and those without (n=22). The two groups were similar in age, sex, Child's stage, transplantation variables, and number and grade of rejection episodes. However, mean transaminases (AST) values in the first 2 weeks were significantly higher levels in shunt versus nonshunt patients (421±335 vs 183±126; P<0.025), and this was even more evident when rejection occurred (626±375 vs 195±129; P<0.001). Furthermore, during an acute rejection reaction, three cases showed a true steal phenomenon through the large reopened shunts with ischemic damage to the grafts. The data indicate a possible detrimental effect of the spontaneous shunts on graft perfusion and suggest the prophylactic surgical interruption of the residual shunts during the transplantation.  相似文献   
25.
Summary In both fast and slow muscles of rats treated with 20–25 diazacholesterol there were qualitative alterations, such as changes of fiber outlines, numerous moth-eaten fibers and rare ring fibers. In addition there were generally larger groups of Type I and intermediate fibers than in normal controls (type-grouping tendency) in the preparations for oxidative enzymes in the extensor digitorum longus (EDL) of myotonic animals. Quantitative evaluations of EDL and soleus of myotonic rats revealed moderate hypotrophy of Type I and Type II fibers with an increase in the number of Type I and of Type III fibers in the EDL and a significant decrease of the nondominant fibers in the soleus muscle. The data are discussed in the light of a neurally mediated and/or direct action of the drug on the muscle fiber.
Zusammenfassung Sowohl in phasischen wie auch in tonischen Muskeln von Ratten, welche mit 20–25 Diazacholesterol behandelt wurden, wurden diskrete Strukturänderungen festgestellt: Änderungen der Umrisse der Einzelfasern, zahlreiche Fasern mit Mottenfraß, seltene Ringfasern. Histochemische Reaktionen für oxidative Enzyme im Extensor digitorum longus myotonischer Tiere zeigten außerdem häufig größere Gruppen von Typ-I-Fasern und Fasern vom Zwischentyp als bei normalen Kontrollen (Tendenz zum Type-Grouping). Quantitative Auswertung zeigte im Extensor digitorum longus und im Soleus myotonischer Ratten eine mäßige Hypotrophie der Typ-I-und Typ-II-Fasern mit einer Zunahme der Anzahl der Fasern vom Typ I und vom Typ III im Extensor digitorum longus und einer signifikanten Abnahme des nicht dominanten Fasertypus im Soleus. Die Befunde werden besonders im Hinblick auf eine neurogen vermittelte oder unmittelbare Wirkung der Substanz auf die Muskelfaser diskutiert.
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26.
During the last 20 years, various conservative surgical techniques have been proposed to treat larynx cancer. On the basis of our various experiences and of the ultrastructural data on the tissues treated with radiowaves, we decided to also use radiosurgery in operations under direct microlaryngoscopy. We select 18 patients suffering from epidermoid carcinoma. These patients had been referred to our ENT clinic at the Polichnico of Palermo between 1999 and 2001. The authors describe the surgical procedures used and emphasize the advantages of radiosurgery in the treatment of larynx cancer.  相似文献   
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Central dopaminergic dysfunction has been suggested to be involved in the pathogenesis of obsessive compulsive disorder (OCD). In 15 patients with OCD and in 15 age-sex matched controls we evaluated the dopamine (DA) function by measuring the cortisol (CORT) responses to stimulation with the DA agonist apomorphine (APO). The CORT response to acute saline administration was also measured, to exclude the existence of a pathology of the circadian secretion of the hormone which could obscure the significance of the CORT response to APO stimulation. Basal levels of CORT were the same in patients and controls, but the values after saline administration were significantly higher in patients than in controls. APO stimulation-induced CORT rises were significantly higher in patients than in controls, but when the data after APO were corrected for those after saline, there were no significant difference between the two groups of subjects. Our data suggest that there are no alterations of the central dopaminergic function connected with the regulation of the hypothalamo-pituitary-adrenal axis in OCD.  相似文献   
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