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51.
Donatella Carretta Anne Herv-Minvielle Victoria M. Bajo Alessandro E. P. Villa Eric M. Rouiller 《Brain research》1999,841(1-2):170-183
Neuronal activity was established in the auditory pathways in relation to behavioural response and cognitive information processing during a sensory-motor acoustic learning. Rats were trained in three consecutive phases. The first phase was an association between an auditory stimulus and a food reward; the second phase a simple discrimination between two sounds of different frequency components, and the third phase a more complex discrimination involving both spectral and spatial sound dimensions. Auditory stimuli were bursts of complex sounds lasting 500 ms. Neuronal activity related to the behaviourally relevant stimuli was established in 20 "learning" rats undergoing this protocol, which were progressively sacrificed at the beginning, middle and end of each phase. For comparison, activity was also established in four "control" rats exposed to the same stimuli delivered pseudo-randomly, thus carrying no behavioural meaning. Neuronal activity was assessed immunocytochemically using the functional marker Fos. To establish a baseline, two rats were unexposed to controlled acoustic stimulation ("unstimulated" rats). In the superior olivary complex (SOC), inferior colliculus (IC) and medial geniculate body (MGB), the number of Fos-like immunopositive cells was comparable in "learning" and "control" animals, but higher than in the "unstimulated" rats. In the auditory cortex (AC), most prominently in the secondary area Te2, the number of Fos-like positive cells differed between "learning" and "control" rats, suggesting that the auditory cortical areas may be involved in the encoding of the behavioural significance of the acoustic stimuli. 相似文献
52.
PURPOSE: Ocular self-injury by psychotic patients is an uncommon cause of ocular morbidity that poses peculiar problems. This report describes a schizophrenic self-injuring patient with scleral rupture and retinal detachment (RD), treated under loco-regional anesthesia. CASE REPORT: A 65-year-old man presented with scleral rupture, hyphema, traumatic lens luxation, vitreous prolapse, vitreous hemorrhage and total RD after deliberately hitting his head. The fellow eye had been successfully operated with scleral buckle surgery for the same reason two years earlier. The patient underwent a two-step surgical procedure under local anesthesia, with repositioning and resection of the uveal prolapse and scleral rupture repair and, separately, lens removal pars plana vitrectomy (PPV), membrane peeling, retinotomy, laser treatment and SiO tamponade. RESULTS: Twelve months after PPV, the cornea was clear, IOP was 16 mmHg, the retina was attached and VA was 20/200. The fellow eye maintained 20/30 VA. CONCLUSIONS: In psychotic patients the intrinsic difficulty of a traumatic RD is combined with systemic illness, no compliance and the risk of recurrence. Although ocular traumas usually require general anesthesia, this patient underwent both interventions under local anesthesia with sedation, because of his psychotic condition and chronic liver failure. Local anesthesia and sedation proved effective in controlling pain and intra-operative compliance even in such a difficult patient. Although it is reasonable to question operating on such patients, we nonetheless believe that every attempt should always be made at gaining useful vision in both eyes since these patients are at a high risk of recurrent ocular trauma. 相似文献
53.
D. De Leo R. Rozzini M. Bernardini M. Zucchetto R. Gallato A. Villa M. Dello Buono F. Grigoletto M. Trabucchi 《Quality of life research》1992,1(6):367-374
This study evaluates the effects of a Tele-check/Tele-emergency service on the quality of life in the elderly. Through telephone interviews a questionnaire has been repeatedly administered to explore various psychological, somatic, and social aspects in a random sample of 574 subjects aged 65 years and over (mean = 76.8 years). The findings suggest that the elderly helped by the service (in its control functioning) make less demands on health facilities (GPs visits, number of days in hospital) as compared to controls. Implications are presented and discussed. 相似文献
54.
C López W Jiménez V Arroyo J Clària G La Villa M Asbert J Gaya F Rivera J Rodés 《Hepatology (Baltimore, Md.)》1991,13(3):585-589
It has been proposed that the initial event of sodium retention in cirrhosis is a peripheral arteriolar vasodilation causing underfilling of the arterial vascular compartment and stimulation of the renin-aldosterone and sympathetic nervous systems. To test this hypothesis, systolic blood pressure, sodium balance and urinary excretion of sodium and aldosterone were sequentially measured in 13 conscious spontaneously hypertensive rats submitted to a cirrhosis induction program with carbon tetrachloride and phenobarbital and in 14 control hypertensive animals. No significant differences were found between control and cirrhotic rats in any of the measured parameters during the first 7 wk of the study. The eighth week sodium retention developed in cirrhotic rats as indicated by a positive sodium balance and a marked decrease of sodium excretion. At the same time a significant reduction in systolic blood pressure and a great increase in urinary excretion of aldosterone were detected. These changes were more marked the ninth week of the study. In cirrhotic rats there was a highly significant direct correlation between systolic blood pressure and urinary sodium excretion. Postmortem examination showed a histological picture of cirrhosis in all animals given carbon tetrachloride and ascites in six of them. These results indicate that the onset of hyperaldosteronism and sodium retention in conscious spontaneously hypertensive rats with carbon tetrachloride-induced cirrhosis is chronologically related to a significant decrease in arterial pressure, thus supporting the "peripheral arterial vasodilation hypothesis" of ascites. 相似文献
55.
Zinc, a new coherent therapy for osteoporosis? 总被引:3,自引:0,他引:3
56.
57.
Marie-Claude Rousseau Michal Abrahamowicz Luisa L Villa Maria Cecilia Costa Thomas E Rohan Eduardo L Franco 《Cancer epidemiology, biomarkers & prevention》2003,12(10):1029-1037
Women infected with multiple human papillomavirus (HPV) types seem to be at higher risk of cervical intraepithelial neoplasia, although there is controversy about whether coinfections are associated with lower or higher grades of dysplasia. There is no established risk factor profile for infection with multiple HPV types. We analyzed data from a prospective cohort of 2,075 Brazilian women to identify determinants of HPV coinfection. Cervical specimens were collected for cytology and HPV DNA detection. Data on baseline and time-dependent putative risk factors were obtained by interview. Baseline predictors of HPV coinfection included younger age, greater number of recent sexual partners, a history of condyloma but not of other sexually transmitted diseases, and younger age at first sexual intercourse. In repeated measures analyses, there was a weak positive association between the number of sexual partners in the time interval between two study visits and the risk of coinfection. Our results suggest that the risk factor profile for HPV coinfection among HPV-infected women shares several similarities with risk factors for any HPV infection. 相似文献
58.
Susi Burgalassi Daniela Monti Annalisa Brignoccoli Ortenzio Fabiani Carla Lenzi Andrea Pirone Patrizia Chetoni 《Journal of ocular pharmacology and therapeutics》2004,20(6):518-532
The aim of this study was to prepare and test an artificial corneal epithelium (reconstituted rabbit corneal epithelium, RRCE) exhibiting barrier characteristics and paracellular permeability similar to those of native rabbit cornea. The RRCE was obtained from a rabbit corneal epithelium (RCE) cell line grown for 8 days in submerged culture, then for 7 days in air-interface conditions on Snapwell polyester membranes. Permeation studies on the RRCE were carried out in comparison with rabbit excised corneas in vitro, using timolol maleate (TM) as the test drug, alone and in association with the following ocular permeation enhancers: benzalkonium chloride, ethylene-diaminetetraacetic acid sodium salt, polyethoxylated castor oil, polyoxyethylene stearyl ether, sodium deoxycholate, and escin. The integrity of the RRCE was assessed by measuring the transepithelial electrical resistance (TEER) during culture time and after every permeation experiment. When TM was tested alone, the permeation parameters (apparent permeability coefficient, lag time) obtained with the RRCE were similar to those of excised rabbit corneas. The artificial epithelium, however, was less sensitive than native cornea to the effect of permeation enhancers. 相似文献
59.
M. Gipponi N. Solari R. Lionetto C. Di Somma G. Villa F. Schenone P. Queirolo F. Cafiero 《European journal of surgical oncology》2005,31(10):1191-1197
AIM: To define the benefit of intraoperative frozen section examination of the sentinel lymph node (sN), and to assess its prognostic value in clinically node-negative melanoma patients. MATERIALS AND METHODS: Between July 1993 and December 2001, 214 patients with Stage I-II cutaneous melanoma underwent sN biopsy; complete follow-up data are available in 169 of 175 patients who underwent preoperative lymphoscintigraphy, lymphatic mapping with Patent Blue-V and radio-guided surgery (RGS). RESULTS: In an initial subset, the sN was identified in 35 out of 39 patients; in the principal group of 169 patients, the sN was detected in all patients. The benefit of frozen section examination, that is the proportion of all patients having intraoperative histologic examination who tested positive, was 17.2% (29/169); notably, in patients with pT(1-2) vs pT(3-4) melanoma the corresponding values were 2.3 and 33.3%, respectively, (P=0.000). Cox regression analysis for overall survival indicated that sN-positive patients had a two-fold increased risk of death; the most significant predictors of relapse-free survival were sN status (P=0.004), age (P=0.015), and T stage grouping (P=0.033). CONCLUSIONS: The sN is a reliable predictor of regional lymph node status in patients with cutaneous melanoma. Frozen section examination can be useful in avoiding a 'two-stage' operative procedure in patients with tumour-positive sN, but its greatest benefit seems to be restricted to patients with pT(3)-pT(4) primary melanoma. 相似文献
60.
Absence of D1 dopamine receptors that stimulate prolactin release in the rat pituitary 总被引:1,自引:0,他引:1
D Cocchi S Ingrassia L Rusconi I Villa E E Müller 《European journal of pharmacology》1987,142(3):425-429
It has been shown recently that SKF 38393-A (2,3,4,5-tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine-7-ol), a D-1 receptor agonist, possesses a prolactin-releasing effect in the rat, though the pituitary or central nervous system location of the receptors involved has not been clarified. The aim of our study was to elucidate this point. SKF 38393-A administered to freely moving adult female and male rats induced a striking, short-lived increase of basal prolactin levels. The prolactin stimulatory effect of SKF 38393-A was counteracted by pretreatment with SCH 23390, A D-1 receptor blocker. SKF 38393-A (10(-11)-10(-6)M) added to monolayer primary cultures of anterior pituitary cells from rats of both sexes failed to modify prolactin release. At higher concentrations (10(-5)-10(-4) M) the drug induced a slight inhibition of prolactin release. Similarly, SKF 38393-A failed to stimulate adenylate cyclase activity in anterior pituitary membranes from rats of both sexes at low concentrations, while it inhibited enzyme activity at higher concentrations (10(-5)-10(-3) M). The latter effect was counteracted by concomitant addition of the antagonist of D-2 receptors, 1-sulpiride. These data demonstrate that: (1) the anterior pituitary does not contain D-1-dopamine receptors (positively coupled to adenylate cyclase) stimulatory to prolactin release; (2) the striking prolactin-releasing effect of SKF 38393-A in the rat is due to activation of extra-pituitary D-1 dopamine receptors; (3) SKF 38393-A, at high concentrations, is capable of activating pituitary D-2 receptors. 相似文献