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11.
BACKGROUND: Major depression has been associated with hypercortisolemia in a subset of patients with depression. Administration of exogenous cortisol and other glucocorticoids to healthy human subjects has been observed to result in a transient impairment in verbal declarative memory function. The purpose of this study was to assess the effects of the glucocorticoid, dexamethasone, on verbal declarative memory function in patients with untreated unipolar major depressive disorder (MDD). METHODS: Fifty two men and women with (n = 28) and without (n = 24) MDD received placebo or dexamethasone (1 mg and 2 mg on 2 successive days) in a double-blind, randomized fashion. Declarative memory was assessed with paragraph recall at baseline (day 1) and day 3. RESULTS: There was a significant interaction between diagnosis and drug (dexamethasone vs. placebo) on paragraph recall. In the healthy subjects, memory improved from baseline to day 3 with placebo and was unchanged with dexamethasone, whereas in MDD patients memory function showed a pattern of decreasing with placebo and improving with dexamethasone from baseline to day 3. CONCLUSIONS: These findings are consistent with an altered sensitivity of declarative memory function in MDD to regulation by glucocorticoids. Possible explanations of the findings include alterations in glucocorticoid receptors in the hippocampus or other brain regions mediating declarative memory, or differential sensitivity to dexamethasone-induced reductions in cortisol, in patients with MDD.  相似文献   
12.
BACKGROUND: The aim of the present randomized study was to determine the effect of adding sufentanil to bupivacaine, compared with bupivacaine alone in caudal block, on the surgical stress response in children. METHODS: The children were premedicated with midazolam 0.5 mg/kg. All children received induction with nitrous oxide and sevoflurane. Anesthesia was maintained with the same volatile agents in the both groups. The children were randomly allocated to two groups. Group I received bupivacaine alone (n = 17) and group II received bupivacaine + sufentanil (n = 16). Caudal block was performed with 0.25% bupivacaine 2 mg/kg (group I) or 0.25% bupivacaine 2 mg/kg with sufentanil 0.5 microg/kg (group II) after induction of anesthesia. Blood samples were obtained after induction of anesthesia (T(0)) to measure baseline concentrations of cortisol, prolactin, glucose and insulin. Additional samples were obtained 30 min after the start of surgery (T(1)), and 60 min after the end of surgery (T(2)). RESULTS: All of the basal values (T(0)) were within the normal ranges of the authors' laboratory for children of this age group and there were no differences between the groups (P > 0.05). In both groups, glucose concentration increased at T(1), compared with T(0) and T(2) (P < 0.05). The glucose concentration was unchanged at T(2) compared with T(0) in both group (P > 0.05). In both groups, prolactin concentration increased at T(1), compared with T(0) and decreased at T(2), compared with T(1) (P < 0.05). Cortisol decreased at T(1) and T(2), compared with T(0) in both groups. (P < 0.05). Insulin concentration remained unchanged at T(0) and T(2), but increased slightly at T(1) in both groups (P > 0.05). There were no significant differences in plasma prolactin, cortisol, glucose and insulin levels between the two groups at T(1) and T(2) (P > 0.05). CONCLUSION: There is no advantage in adding 0.5 microg/kg sufentanil to bupivacaine over bupivacaine alone in the caudal block, with regard to the surgical stress response in children.  相似文献   
13.
Two topical corticosteroids, budesonide (BUD) and beclomethasone dipropionate (BDP), both administered as suspensions in water, were investigated in healthy volunteers regarding influence on cortisol in plasma and urine (U-cortisol) after nasal application. In the first study, single doses of 200, 400, and 800 μg of BDP and BUD were given at 10:00 pm. In the second study, 100, 200, and 400 μg were given mornings and evenings for 4 days. In the single-dose study, none of the drugs or doses showed any significant influence on cortisol in plasma. However, U-cortisol decreased significantly after BUD 400 and 800 μg. In the multidose study, U-cortisol values were significantly reduced after all doses of BUD and the highest dose of BDP. The compounds tested showed different ability to cause measurable systemic effects after nasal application. The clinical implication is that the prescriber, when choosing a compound, should take the application site into consideration and should also be encouraged to find the lowest effective dose.  相似文献   
14.
目的 :观察星状神经节阻滞 (SGB)对福尔马林炎症痛家兔血清皮质醇 (CS)和炎症局部 β -内啡肽 (β -EP)含量的影响。方法 :选择健康家兔 1 6只 ,随机分为SGB组和对照组 ,各 8只。两组均用 8%福尔马林 0 .5ml在右前肢足底皮下注射致痛 ,致痛前 1 0minSGB组经预置导管给 0 .2 5 %布比卡因 0 .5ml,对照组给等量生理盐水。用放免法测定致痛前 1 0min(T0 )、致痛后 1 0、60和 1 2 0min(T1 、T2 和T3)血清CS及致痛 1 2 0min炎症局部 β-EP含量。结果 :致痛后对照组血清CS在各时点均较致痛前升高 ,且在T2 时达高峰 (P <0 .0 1 ) ,而SGB组各时点较致痛前无明显差异 (P >0 .0 5) ;两组相比 ,T0 时无差异 (P >0 .0 5) ,而在T1 、T2 和T3时有明显差异 (P <0 .0 5 ,P<0 .0 1 )。SGB组致痛后 1 2 0min时炎症局部 β -EP含量明显高于对照组 (P <0 .0 1 )。 结论 :SGB可抑制福尔马林刺激引起的血清CS的升高 ,并且可增加炎症局部 β-EP含量  相似文献   
15.
观察了172例脑卒中患者血清促肾上腺皮质激素(ACTH)、皮质醇的变化,发现ACTH、皮质醇水平明显高于正常对照组,脑出血组高于脑梗塞组;病情轻重与ACTH、皮质醇的变化明显相关。治疗前后ACTH、皮质醇水平明显不同,治疗后明显降低(P<0.01)。说明治疗后可改善下丘脑-垂体-肾上腺皮质轴(H/P/A)功能紊乱。  相似文献   
16.
Summary In order to establish whether the inhibitory control exerted by endogenous opioid peptides on ACTH/cortisol secretion changes in patients affected by Parkinson's disease, ten parkinsonian male subjects and eight age matched normal controls were tested with naloxone (4 mg an i.v. bolus plus 10 mg infused in two hours). In a different occasion all subjects were tested with normal saline. Experiments started at 09.00 h. Plasma ACTH and cortisol concentrations showed a slight physiological decline during saline test in both groups. In the normal controls and in the parkinsonian patients both ACTH and cortisol levels were significantly higher after naloxone administration than during saline test. However, both naloxone induced ACTH and cortisol responses were significantly higher in normal than in parkinsonian subjects. In agreement with the well-known opioid deficiency characterizing the parkinsonian brain, these data show a reduced opioid inhibitory control of ACTH/cortisol secretion in patients with Parkinson's disease.  相似文献   
17.
1. The present study investigated the effect of prior administration of nifedipine on AVP-induced ACTH release in seven normal volunteers. Three protocols were used: 20 mg oral nifedipine; 0.14 pressor units intramuscular (i.m.) per kg bodyweight aqueous AVP; oral nifedipine plus i.m. AVP 90 min later. Plasma ACTH and cortisol were measured at intervals for 2.5 h during each test. 2. The mean peak plasma ACTH and cortisol levels and the mean peak changes from basal in these levels were significantly lower in the nifedipine/AVP test than in the AVP alone test. The integrated area under the cortisol time curve was significantly lower for the nifedipine/AVP test than that for the AVP test alone. Nifedipine alone caused no changes in ACTH or cortisol. 3. Acute administration of oral nifedipine caused an inhibition of AVP-stimulated ACTH and cortisol release in normal humans. This effect may be due to blockade of plasma membrane calcium channels normally activated during AVP stimulation of pituitary corticotrophs.  相似文献   
18.
19.
We assessed the effect of long-term therapy with inhaled beclomethasone dipropionate (BDP) on the pituitary-adrenal axis, by measuring the integrated concentration (IC) of plasma cortisol in eight children with asthma (age, 6-16 years) who regularly used inhaled BDP in doses ranging from 8 to 26.5 micrograms/kg (200-450 micrograms/day) for 6 months to 4 years. The control group included six children (age, 6-16 years) who had the IC of plasma cortisol measured as part of an endocrinological evaluation and were found to be healthy. Cortisol concentration was measured in blood samples collected continuously over a 24-hr period. Mean IC of plasma cortisol in the study group was significantly lower than in the healthy controls (mean +/- SD, 4.9 +/- 3.3 vs 9.1 +/- 1.9 micrograms/mL; P less than 0.02). Cortisol response to 0.25 mg ACTH (iv) was abnormal in one of the eight BDP-treated patients. No correlation was found between IC of plasma cortisol and the BDP dose, severity of asthma, height percentile, or the Tanner stage. We conclude that long-term therapy, even with relatively conventional doses of inhaled BDP may cause reduction in the normal physiological secretion of cortisol. The clinical relevance of low IC of plasma cortisol is not clear, but it may reflect partial suppression of the pituitary-adrenal axis.  相似文献   
20.
166例涎腺腺样囊性癌的临床病理分析   总被引:1,自引:0,他引:1  
金蓉 《海南医学》2003,14(10):17-18
目的 分析涎腺腺样囊性癌的临床病理特点。方法 对166例涎腺腺样囊性癌行临床资料总结和HE组织学观察。结果 本组腺样囊性癌占涎腺上皮性肿瘤的11.5%,占涎腺癌的27.0%;男性略多于女性;中年以上好发;发生于小涎腺者多于大涎腺,以腭部为最常见;腺样型103例,管状型42例,实性型2l例;Ⅰ级17例,Ⅱ级128例,Ⅲ级2l例。结论 需与基底细胞腺癌、涎腺导管癌、多形性低度恶性腺癌、上皮-肌上皮癌鉴别诊断;浸润性极强是其显著特点,手术治疗以局部大块切除为主要原则。  相似文献   
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