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61.
The present article reviews the state of public debate and legal provisions concerning end‐of‐life decision‐making in Italy and offers an evaluation of the moral and legal issues involved. The article further examines the content of a recent law concerning informed consent and advance treatment directives, the main court pronouncements that formed the basis for the law, and developments in the public debate and important jurisprudential acts subsequent to its approval. The moral and legal grounds for a positive evaluation of this law, which attests that the patient may withhold or withdraw from life‐prolonging treatment, will be offered with reference to liberal approaches and particularly to the frameworks of care and virtue ethics; but reasons will also be offered in order to consider not only the latter but also broader range of end‐of‐life treatment decisions as morally apt options. In this light, we argue in favour of a further development of the Italian legislation to encompass forms of assisted suicide and active euthanasia.  相似文献   
62.
目的:探讨脊髓水平诱导型一氧化氮合酶在吗啡依赖大鼠戒断反应中的作用。方法:健康雄性SD大鼠72只,体重200~250 g,吗啡剂量每次10 mg/kg,每日2次,隔日每次增加10 mg/kg,至第6天末次注射50 mg/kg,大鼠腹腔注射纳洛酮4 mg/kg建立吗啡依赖及戒断模型,在纳洛酮激发戒断前30 min鞘内注射iNOS特异性抑制剂氨基胍(AG)150μg。分为正常对照组、吗啡依赖组、吗啡戒断组、AG组。采用行为学(n=8)、免疫组织化学(n=6)和Western blot(n=4)方法观察鞘内应用iNOS特异性抑制剂氨基胍对吗啡依赖大鼠纳洛酮催促戒断反应和脊髓神经元iNOS表达的影响。结果:AG组戒断症状评分和戒断组促诱发痛评分均低于戒断组(P<0.05)。免疫组织化学和Western blot显示戒断组大鼠脊髓iNOS阳性神经元的数目和蛋白的表达增高,而AG组大鼠脊髓iNOS阳性神经元的数目和iNOS蛋白的表达低于戒断组(P<0.05)。结论:脊髓水平iNOS表达上调可能参与介导吗啡戒断反应。  相似文献   
63.
大鼠肠易激综合征模型的建立及其评价   总被引:1,自引:0,他引:1  
目的探讨腹泻型肠易激综合征(D-IBS)动物模型的建立方法,为临床治疗提供依据。方法雄性Wistar大鼠40只,随机分为IBS1(乙酸灌肠加束缚应激)组I、BS2(束缚应激)组、灌肠对照组和正常对照组,采用乙酸灌肠加束缚应激和Williams方法制作IBS动物模型,用腹壁撤退反射(AWR)评分和腹外斜肌放电活动检测对其内脏敏感性进行评估,同时进行组织学检查对肠黏膜组织的组织学改变进行评价。结果两模型组大鼠AWR评分和腹外斜肌收缩次数在不同扩张容量下均较对照组明显增加(P〈0.05)。组织学分析显示各组大鼠均无明显的炎症性表现。结论乙酸灌肠加束缚应激和Williams方法制成的IBS动物模型符合IBS的内脏敏感性机制,可用于IBS的试验研究。  相似文献   
64.
He JH  Cao JL  Xu YB  Song XS  Ding HL  Zeng YM 《生理学报》2005,57(5):557-565
在大鼠吗啡依赖和戒断模型上,采用行为学、免疫组织化学和Western blot方法观察吗啡依赖及戒断大鼠脊髓神经元磷酸化细胞外信号调节激酶(phospho-extracellular signal-regulated kinase,pERK)表达的变化,及鞘内注射促分裂原活化蛋白激酶激酶(mitogen-activated protein kinase kinase,MEK)抑制剂U0126或ERK反义寡核苷酸对吗啡依赖大鼠纳洛酮催促戒断反应、触诱发痛及脊髓神经元pERK表达的影响,探讨脊髓水平pERK在介导吗啡依赖和戒断过程中的作用。结果显示:(1)在吗啡依赖形成过程中,大鼠脊髓胞浆与胞核非磷酸化ERK表达没有改变,但pERK表达逐渐增加,纳洛酮催促戒断后,仍有进一步增加的趋势,戒断1h后,其表达量明显下降,但仍高于对照组。(2)鞘内预先注射MEK抑制剂U0126或ERK反义寡核苷酸能明显抑制吗啡戒断反应和戒断引起的痛觉异常;与行为学结果一致,脊髓背角pERK阳性神经元表达与脊髓胞浆和胞核pERK表达也明显降低。上述结果提示,脊髓水平ERK激活和核转位参与吗啡依赖的形成及戒断反应的表达。  相似文献   
65.
The zebrafish has been in the forefront of developmental genetics for decades and has also been gaining attention in neurobehavioral genetics. It has been proposed to model alcohol-induced changes in human brain function and behavior. Here, adult zebrafish populations, AB and SF (short-fin wild type), were exposed to chronic treatment (several days in 0.00% or 0.50% alcohol v/v) and a subsequent acute treatment (1 h in 0.00%, 0.25%, 0.50% or 1.00% alcohol). Behavioral responses of zebrafish to computer-animated images, including a zebrafish shoal and a predator, were quantified using videotracking. Neurochemical changes in the dopaminergic and serotoninergic systems in the brain of the fish were measured using high-precision liquid chromatography with electrochemical detection. The results showed genetic differences in numerous aspects of alcohol-induced changes, including, for the first time, the behavioral effects of withdrawal from alcohol and neurochemical responses to alcohol. For example, withdrawal from alcohol abolished shoaling and increased dopamine and 3,4-dihydroxyphenylacetic acid in AB but not in SF fish. The findings show that, first, acute and chronic alcohol induced changes are quantifiable with automated behavioral paradigms; second, robust neurochemical changes are also detectable; and third, genetic factors influence both alcohol-induced behavioral and neurotransmitter level changes. Although the causal relationship underlying the alcohol-induced changes in behavior and neurochemistry is speculative at this point, the results suggest that zebrafish will be a useful tool for the analysis of the biological mechanisms of alcohol-induced functional changes in the adult brain.  相似文献   
66.
In this study, we determined the efficacy of minocycline, a second generation tetracycline, in preventing male germ cell apoptosis after withdrawal of gonadotropins and intratesticular testosterone (T). Groups of 5 male rats received one of the following treatments daily for 5 days: (i) daily sc injection of GnRH-A (1.6 mg/kg BW), (ii) oral administration of 30% gum acacia as a vehicle control, and (iii) GnRH-A + oral administration of 50 or 100 mg/kg BW of minocycline. Minocycline at both 50 and 100 mg dose levels significantly (P < 0.05) prevented GnRH-A -induced germ cell apoptosis by 59.4% and 62.2%, respectively, and fully prevented PARP cleavage. Minocycline-mediated protection occurred at the mitochondria, involving the restoration of the BCL-2 levels and, in turn, suppression of cytochrome c and DIABLO release. Minocycline was also effective in preventing human male germ cell apoptosis induced by hormone free culture condition.  相似文献   
67.
目的:研究鞘内注射细胞外信号调节激酶(ERK)抑制剂U0126对吗啡依赖大鼠纳洛酮催促戒断反应、脊髓磷酸化cAMP反应元件结合蛋白(p-CREB)表达的影响。方法:建立大鼠吗啡依赖和戒断模型,分为正常对照组、吗啡依赖组、吗啡戒断组、U0126组、溶媒(DMSO)组,采用行为学(n=8)、免疫组织化学(n=6)和Western blot(n=4)方法观察鞘内应用U0126对吗啡依赖大鼠纳洛酮催促戒断反应、脊髓p-CREB表达的影响。结果:①鞘内注射u0126可明显减轻吗啡依赖大鼠戒断症状,戒断组戒断症状评分为28.6±4.89,U0126组为22.5±4.09(P〈0.05);戒断组促诱发痛评分(TEAscore)为13.5±2.55,U0126组为10.0±2.76(P〈0.05)。②鞘内注射U0126可明显减少胸腰段脊髓背角p-CREB阳性神经元的数目,U0126组为287±54,低于戒断组(380±71,P〈0.05)。 ③westem blot结果显示:鞘内注射U0126明显抑制吗啡戒断期间脊髓p-CREB表达的增加。结论:鞘内注射U0126能明显抑制吗啡戒断大鼠脊髓神经元p-CREB的表达。  相似文献   
68.
Keyword index     
《Journal of neurochemistry》2003,87(6):1579-1582
  相似文献   
69.
Quantitative autoradiography of [14C]deoxyglucose, [14C]iodoantipyrine, and [14C]leucine was used to estimate regional cerebral glucose metabolism, cerebral blood flow, and cerebral protein synthesis, respectively, in rats during morphine dependence and withdrawal. Glucose metabolism was elevated in 19 of 26 selected brain regions; the elevations in glucose metabolism were similar when data were expressed as either optical density ratios or as calculated rate values of mol/100 gm/min. Restraining the rats produced heterogeneous effects on glucose metabolism during morphine withdrawal (MW). Neither estimated cerebral blood flow nor cerebral protein synthesis were affected by morphine and/or naloxone treatments in either naive or morphine-dependent rats. The data demonstrate that changes in regional cerebral glucose utilization occur independently of blood flow changes and exclude the possibility that regional changes in glucose utilization occur as a consequence of large regional changes in protein synthesis rates in brain. These data confirm the utility of 2-deoxyglucose measures of MW as objective biochemical indices of opiate agonist and antagonist effects in vivo.  相似文献   
70.
The medial habenula (MHb) plays an important role in nicotine-related behaviors, such as aversion and withdrawal. The MHb is composed of distinct subregions with unique neurotransmitter expression and neuronal connectivity. Here, we showed that nicotine and substance P (SP) differentially regulate neuronal excitability in subdivisions of the MHb (ventrolateral division, MHbVL; dorsal division; MHbD and superior division: MHbS). Nicotine remarkably increased spontaneous neuronal firing in the MHbVL and MHbD, but not in the MHbS, which was consistent with different magnitudes of whole-cell inward currents evoked by nicotine in each subdivision. Meanwhile, SP enhanced neuronal excitability in the MHbVL and MHbS. Although the MHbD is composed of SP-expressing neurons, they did not respond to SP. Neurons in the MHbVL increased their firing in response to bath-applied nicotine, which was attenuated by neurokinin receptor antagonists. Furthermore, nicotine addiction and withdrawal attenuated and augmented excitatory SP effects in the MHbVL, respectively. On the whole, we suggest that MHb-involving nicotine-related behaviors might be associated with SP signaling in MHb subdivisions.  相似文献   
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