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31.
Jamie C. Day Pier Vincenzo Piazza Michel Le Moal Stefania Maccari 《The European journal of neuroscience》1997,9(6):1130-1136
An influence on drug-taking behaviours of the stress-related hypothalamo-pituitary-adrenal (HPA) axis and its final hormonal mediator, corticosterone, has previously been demonstrated. A role for cortically projecting cholinergic neurons in these behaviours can also be proposed. The experiments presented here examine the effect of the drug of abuse cocaine (15 mg/kg) on the release of acetylcholine (ACh) in the cortex of freely moving rats, using the technique of in vivo microdialysis. To assess a possible modulatory influence of the HPA axis via its final hormonal mediator corticosterone, the cocaine-induced effect on cortical ACh release in intact rats was compared to that in adrenalectomized (ADX) rats, which thus lacked their endogenous source of corticosterone, and in ADX rats in which the cocaine-induced corticosterone peak and/or the basal circadian concentrations of serum corticosterone were simulated by replacement treatments. The results reported here demonstrate that cortical ACh release is greatly increased by cocaine in intact rats; ADX prolongs the return to basal levels of cortical ACh, and the chronic replacement of circadian levels of corticosterone normalizes this effect. In contrast, during the plateau period of cocaine-induced increased cortical ACh release, where no effect of ADX is evident, rats with chronic replacement of corticosterone show an attenuated cocaine-induced cortical ACh release, and the acute replacement of the cocaine-induced corticosterone secretion further attenuates this response. These results demonstrate that cocaine stimulates cortically projecting cholinergic neurons, and that the HPA hormone corticosterone modulates this interaction in a complex manner which merits further investigation. 相似文献
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34.
Giuseppe Giuffre’ Vincenzo Schifano Maria Vadala’ 《Documenta ophthalmologica. Advances in ophthalmology》1995,91(3):255-263
We report on a case of idiopathic uveal effusion syndrome complicated by AION. To our knowledge such an association hasn't been previously described. We suggest that scleral thickening caused obstruction of vortex veins followed by uveal effusion and compression of posterior ciliary arteries within their intrascleral tract, leading to AION. Nevertheless it can't be excluded that AION was the result of mechanical compression on ciliary vessels of optic disc by choroidal detachment. 相似文献
35.
Francesco Franceschi Umile Giuseppe Longo Laura Ruzzini Paolo Simoni Bruno Beomonte Zobel Vincenzo Denaro 《Knee surgery, sports traumatology, arthroscopy》2007,15(3):266-268
Bilateral discoid medial menisci is an extremely rare condition of the knee and it can be associated to other pathological
findings, including anterior portion cyst formation. We report on the clinical features, radiographic findings, treatment
and results of one patient who presented a bilateral medial discoid meniscus combined with posterior portion cyst of the left
knee. To the best of the author’s knowledge, this is the first case of bilateral medial discoid meniscus associated with posterior
portion cyst formation. 相似文献
36.
Vincenzo De Giorgi MD Daniela Massi MD Elisa Trez MD Camilla Salvini MD Elena Quercioli MD Paolo Carli MD 《Dermatologic surgery》2003,29(9):965-967
In dermoscopy, the correct recognition of the single parameters is fundamental to achieve great diagnostic accuracy, but the scarce morphologic expression of a parameter may lead to diagnostic errors. We report the case of a 27-year-old white man presenting a pigmented lesion of the back, which was present since puberty. Clinical examination revealed on the back the presence of a flat, gray-blue lesion and at the periphery a small dark-brown papule. An assessment of the lesion by means of dermoscopy was performed. The purpose of this report was to analyze the Blue Hue in dermoscopy with its histopathologic correlates, starting with the discussion of a clinical case. 相似文献
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Italy's mental health law of 1978 provided for the gradual phasing out of psychiatric hospitals (PH) and the creation of comprehensive community-based systems. However, these changes have taken place at different times and in different forms. There are now three different organizational and care models operating in Italy: in the first, common in Southern Italy, the former PH and the new general hospital general wards (GHPW) coexist; in the second, outpatient departments complement the above facilities, but the hospital activity remains central; in the third model, a community model has been given priority-the so-called community priority. While many reports have been published describing the activity of some of the services adhering to the third model, no report has been published specifically describing the activity of services which work according to the second model, such as Cremona. In this paper, the activity of the Cremona psychiatric services is described, and the consequences of the reform law and the problems related to an hospital-based activity are emphasized. 相似文献
39.
Ilaria Marigo Luigi Dolcetti Paolo Serafini Paola Zanovello Vincenzo Bronte 《Immunological reviews》2008,222(1):162-179
Summary: Emerging evidence indicates that the Achilles' heel of cancer immunotherapies is often the complex interplay of tumor-derived factors and deviant host properties, which involve a wide range of immune elements in the lymphoid and myeloid compartments. Regulatory lymphocytes, tumor-conditioned myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages, and dysfunctional and immature dendritic cells take part in a complex immunoregulatory network. Despite the fact that some mechanisms governing tumor-induced immune tolerance and suppression are starting to be better understood and their complexity dissected, little is known about the diachronic picture of immune tolerance. Based on observations of MDSCs, we present a time-structured and topologically consistent idea of tumor-dependent tolerance progression in tumor-bearing hosts. 相似文献
40.
Palma E Muscoli C Mancuso E Sculco F Sacco I Alecce W Costa N Colica C Cristiano D Rotiroti D Mollace V 《Neuroscience letters》2004,368(1):112-115
In the last few decades, cholinergic connections located into posterior hypothalamus (PH) have been implicated in the central regulation of blood pressure (BP). Here we investigated the role of nitric oxide (NO) in the blood pressure response elicited by infusion of physostigmine into PH of normotensive rats. In freely moving rats, physostigmine (60-200 nM) produced a dose- and time-dependent elevation of BP which was antagonized by the antimuscarinic drug scopolamine (60 nM) and by L-NAME (100 microM), an inhibitor of NO synthase, both infused into the same site. In contrast, L-arginine (L-Arg; 100 microM), the precursor of NO, and glyceryltrinitrate (GTN; 140 nM), an NO donor, infused into the PH did not affect physostigmine-related pressor response. In rats pre-treated with Escherichia coli lipopolisaccharide (LPS; 0.5 microg i.p. 24h beforehand), however, scopolamine, L-Arg and GTN produced a decrease of BP, an effect antagonized by L-NAME. This suggests that NO only slightly modulates physostigmine-related pressor response elicited into PH of LPS-untreated rats. In contrast, the release of large amounts of NO generated by pre-treating rats with LPS, down-regulates cholinergic connections located at the PH, thus contributing in the central dysregulation of BP which can be found when high circulating endotoxin levels may occur. 相似文献