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M Morales-Ruiz W Jiménez J Ros M Solé A Leivas M Bosch-Marcé F Rivera V Arroyo J Rodés 《Canadian Metallurgical Quarterly》1997,112(6):2056-2064
BACKGROUND & AIMS: Patients and rats with cirrhosis and ascites are prone to develop peritonitis. The aim of this study was to assess whether peritoneal macrophages of cirrhotic rats without peritoneal infection produce nitric oxide and express inducible NO synthase (iNOS). METHODS: NO2- accumulation produced by macrophages from control rats and cirrhotic rats with ascites was determined. iNOS messenger RNA and protein expression were analyzed by Northern and Western blot and immunocytochemical analysis. The in vivo effects of inhibiting iNOS were investigated by giving the specific iNOS inhibitor L-N-(1-iminoethyl)-lysine (L-NIL) or sterile saline to 9 and 7 cirrhotic rats with ascites, respectively. RESULTS: Cirrhotic macrophages produced NO2- that was around fourfold greater than that of control macrophages after 30 hours in culture. Northern and Western blot and immunocytochemical analysis showed the presence of iNOS messenger RNA and protein in macrophages of cirrhotic rats. Ascites cultures were positive in all rats administered L-NIL and negative in those administered saline. CONCLUSIONS: Macrophages of cirrhotic rats produce NO and express iNOS messenger RNA and protein, and these changes are not a consequence of overt bacterial infection. Because iNOS inhibition results in peritoneal infection, these results suggest that iNOS induction in macrophages of cirrhotic rats is a host defense response to prevent bacterial peritonitis. 相似文献
64.
Reports responses to a questionnaire secured from 80 approved internship centers on various aspects of training in diagnostic testing. While there was some variation from center to center, a majority believed that university training was inadequate, and a number of them perceived the university as instilling an overly critical attitude toward diagnostic testing in their students. The techniques emphasized in internship training are presented, and the implications of the differences in emphases between academic and field settings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Garfield Sol L.; Prager Richard A.; Bergin Allen E. 《Canadian Metallurgical Quarterly》1971,37(3):320
Discusses issues raised by D. Fiske (see pa, vol. 47:issue 5) and by L. Luborsky (see pa, vol. 47:issue 5) with reference to outcome research in psychotherapy generally, and to a previous paper by the authors (see pa, vol. 47:issue 5 ) in particular. While attention in the past has tended to focus on general criteria of improvement, it is believed that in the future more consideration must be given to the specific changes sought by means of therapy with multiple measures devised for appraising such change. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
SA Kates BF McGuinness C Blackburn GW Griffin NA Solé G Barany F Albericio 《Canadian Metallurgical Quarterly》1998,47(5):365-380
In the rat dorsal hippocampus and dorsal raphe nucleus, the microiontophoretic application of ergotamine and 5-HT suppressed the firing activity of CA3 pyramidal neurons and 5-HT neurons, an effect antagonized by selective 5-HT1A receptor antagonists. Co-application of ergotamine prevented the inhibitory action of 5-HT on the firing activity of CA3 pyramidal neurons but not of 5-HT neurons, indicating that ergotamine acted as a partial 5-HT1A receptor agonist in the dorsal hippocampus and as a full agonist at 5-HT1A autoreceptors. Ergotamine decreased, in a concentration-dependent manner, the electrically evoked release of [3H]5-HT in preloaded rat and guinea pig hypothalamus slices; this effect was prevented by the nonselective 5-HT receptor antagonist methiothepin but not by the selective 5-HT1B/1D receptor antagonist GR 127935 or the alpha 2-adrenoceptor antagonist idazoxan. Although body temperature in humans remained unchanged following inhaled ergotamine, in the rat, subcutaneously injected ergotamine produced a hypothermia that was prevented by a pretreatment with the 5-HT1A/1B receptor/beta-adrenoceptor antagonist pindolol. Finally in humans, ergotamine did not alter prolactin or adrenocorticotropic hormone levels, but increased growth hormone level, which was prevented by pindolol. Cortisol level was increased in humans by ergotamine, but this enhancement was unaltered by pindolol. In conclusion, the present results suggest that ergotamine acted in the rat brain as a 5-HT1A receptor agonist and as an agonist of terminal 5-HT autoreceptor of a yet undefined subtype. In humans, ergotamine also displayed some 5-HT1A receptor activity but, probably because of lack of receptor selectivity, it did not present the same profile as other 5-HT1A receptor agonists. 相似文献
68.
Torosian Tracey; Lumley Mark A.; Pickard Sol D.; Ketterer Mark W. 《Canadian Metallurgical Quarterly》1997,16(2):123
This study examined the relationship of psychological, cardiac, and general medical history factors to asymptomatic (silent) versus symptomatic myocardial ischemia among 102 patients who underwent treadmill exercise testing and had perfusion imaging indicative of ischemia. During exercise, 68 patients exhibited silent ischemia, and 34 experienced chest pain. Patients with silent ischemia rated higher than symptomatic patients on anger control, externally oriented thinking, and somatosensory amplification, but did not differ on depression or global alexithymia. Anger control and externally oriented thinking remained independent correlates in multivariate analysis, controlling for demographic and cardiac factors. Groups did not differ on general medical or cardiac variables. Thus, this study suggests that affective and cognitive factors, but not biomedical factors, are associated with silent, as opposed to symptomatic, ischemia during exercise testing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Patients free from occlusal dysfunction rarely have their teeth together. But, when occlusion does occur (i.e., swallowing), the contacts should be simultaneous and in such a manner as to direct the vector of force down the long axis of the tooth or implant. The incline planes should not touch. 相似文献
70.
Comments on T. C. Wade and T. B. Baker's (see record 1978-20152-001) survey of clinical psychologists' opinions and use of psychological tests. The relatively small sample size in the study is criticized as being nonrepresentative of the population studied, and the time spent on testing activities needs clarification. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献