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971.
在耳鼻咽喉科手术中应用颈外动脉栓塞法10例,形成栓塞组,并把单纯颈外动脉结扎10例作为对照组。结果表明:栓塞组较对照组术中出血量显著减少,有利于病灶彻底清除,因而有提高治愈率减少复发率的作用。掌握栓塞位置、栓塞剂用量和注射速度是防止并发症的关键。  相似文献   
972.
Wilson's disease (WD) is an inherited disorder of copper metabolism yielding marked motor deficits, including a severely disabling tremor. As a structural correlate of the disease, a variety of cerebral abnormalities has been revealed. However, the relationship between motor deficits and cerebral lesions has remained largely unknown. Here, we investigated correlation between WD tremor and cerebral magnetic resonance imaging (MRI) findings. Cerebral MRI abnormalities in 6 symptomatic WD patients were compared to findings in 6 asymptomatic WD patients and 10 healthy controls. All patients were treated with long-term copper chelating therapy. Motor symptoms including tremor were determined by Unified Parkinson's Disease Rating Scale Part III (UPDRS-III). MRI findings in symptomatic WD patients revealed significant symmetric T2*-weighted hypointense signal alterations of globus pallidus, head of the caudate nucleus, and substantia nigra. In contrast, MRI of asymptomatic WD patients did not differ from healthy controls. Correlation analysis revealed a significant positive correlation between MRI basal ganglia lesions and UPDRS action tremor score. Our results demonstrate for the first time that Wilson's disease tremor is associated with lesions of the globus pallidus, the head of the caudate nucleus, and the substantia nigra.  相似文献   
973.
目的:评估早期Alzheimer病患者语义记忆损害。方法:自编语义记忆测试工具,对22例Alzheimer病患者语义记忆损害评估作了纵向的研究.其中男10例,女12例。同时进行简明精神状况量表评定。结果:AD患者的2次MMSE评分明显差于正常对照组(P〈O.001)。在两个词的并列关系中,AD患者语义性启动操作起初并不同步。在并列条件测试中.先出现高启动效应.然后下降。在特征条件测试中,始终呈低启动效应。结论:AD病患者有着显著的动态语义记忆退化。  相似文献   
974.
975.
The objective of this study was to test the impact of entacapone (ENT) addition to levodopa with a decarboxylase inhibitor (LD) in full-time-employed patients with Parkinson's disease (PD), focusing on retirement rates, medical absenteeism, self-perception of disability, as well as motor assessments of parkinsonism, motor fluctuations, and dyskinesias. Thirty full-time-employed PD patients (disease onset before age 60 years) and on optimized monotherapy with LD exhibiting minor motor fluctuations or dyskinesias were entered into a 2-year randomized double-blind placebo-controlled study of ENT adjunctive therapy. The outcome measures were the number of full-time-employed patients at study end, cumulative days of medical absenteeism, patient-completed disability assessments, diary records, and the Unified Parkinson's Disease Rating Scale-based measures of motor fluctuations and dyskinesias. LD + ENT treatment was associated with a lower retirement rate (2 [17%] of 12 vs. 6 [50%] of 12; P = 0.12), lower absenteeism rate (21.5 vs. 43.5 days; P < 0.0001), improved self-perception of disability progression over 2 years (change score 1.0 vs. 4.5; P < 0.0001), and lower scores for both motor fluctuations and dyskinesia assessments compared to LD monotherapy. In this pilot study, LD with ENT adjunctive therapy positively influenced employment rate over 2 years; this effect was associated with reduced motor complications and patient perceptions of stabilized disability.  相似文献   
976.
目的腹内侧前额叶皮质在随意运动的起始和控制、情感以及认知中具有重要作用。然而,黑质-纹状体通路变性后腹内侧前额叶皮质的神经活动和5-HT_(1A)受体的作用仍不清楚。本研究观察了6-羟基多巴胺(6- hydroxydopamine,6-OHDA)损毁黑质致密部(substantia nigra pars compacta,SNc)后大鼠腹内侧前额叶皮质神经活动的变化和体循环给予选择性5-HT_(1A)受体拮抗剂WAY-100635后神经元活动的改变。方法采用在体玻璃微电极细胞外记录方法,记录正常大鼠和SNc单侧损毁大鼠的腹内侧前额叶皮质神经元的活动。结果6-OHDA损毁SNc大鼠的腹内侧前额叶皮质神经元放电频率显著增加,放电形式没有明显改变。体循环给予WAY-100635 (0.1 mg/kg,i.v.)不改变正常大鼠腹内侧前额叶皮质神经元的平均放电频率和放电形式,而显著降低了SNc损毁大鼠前额叶皮质神经元的平均放电频率。结论黑质-纹状体通路的变性可导致腹内侧前额叶皮质神经活动增强,5-HT_(1A)受体拮抗剂WAY-100635可以抑制这种活动增强,提示可能存在腹内侧前额叶皮质5-HT_(1A)受体功能失调。  相似文献   
977.
BACKGROUND: Major depressive disorder (MDD) shows increased coronary artery disease (CAD) risk of unknown mechanism(s). MDD is more common in women than men; CAD diagnosis can be difficult in women. Elevations of the inflammatory markers C-reactive protein (CRP) and serum amyloid A (SAA) predict increased CAD risk in populations; few data on these markers exist in MDD, particularly in remitted patients. METHODS: We measured fasting am serum CRP (high sensitivity, CRP(hs)) and SAA in 18 unmedicated, remitted women with MDD (mean age 41 +/- (SD)12, body mass index (BMI) 25.2 +/- 4.1 kg/m(2)) and 18 BMI-matched healthy control subjects (age 36 +/- 10, BMI 25.3 +/- 3.8 kg/m(2)) on 2 separate occasions, > or = 6 days apart. RESULTS: Repeat SAA and CRP(hs) measurements strongly correlated across study days (SAA: r = .83, p < .001; CRP(hs): r = .94, p < .001). Both SAA (5.30 +/- 3.39 vs. 2.84 +/- 1.87 mg/L, p < .005) and CRP(hs) (3.23 +/- 3.17 vs. 1.12 +/- 1.45 mg/L; p < .01) were significantly elevated in MDD women versus controls. CONCLUSIONS: Elevated SAA and CRP(hs) in remitted, unmedicated women with MDD indicate a pro-inflammatory state unrelated to current depressive symptoms or pharmacotherapy. These findings suggest that inflammatory mechanisms may in part underlie findings of increased CAD risk in MDD.  相似文献   
978.
BACKGROUND: We examined the activation pattern of extracellular signal-regulated kinase 1 and 2 (ERK1/2) and its dependence on D1 versus D2 dopamine receptors in hemiparkinsonian rats treated with 3,4-dihydroxyphenyl-L-alanine (L-DOPA). METHODS: 6-Hydroxydopamine-lesioned rats were treated acutely or chronically with L-DOPA in combination with antagonists for D1 or D2 receptors. Development of dyskinesia was monitored in animals receiving chronic drug treatment. Phosphorylation of ERK1/2, mitogen- and stress-activated protein kinase-1 (MSK-1), and the levels of FosB/DeltaFosB expression were examined immunohistochemically. RESULTS: L-DOPA treatment caused phosphorylation of ERK1/2 in the dopamine-denervated striatum after acute and chronic administration. Similar levels were observed in matrix and striosomes, and in enkephalin-positive and dynorphin-positive neurons. The severity of dyskinesia was positively correlated with phospho-ERK1/2 levels. Phosphorylation of ERK1/2 and MSK-1 was dose-dependently blocked by SCH23390, but not by raclopride. SCH23390 also inhibited the development of dyskinesia and the induction of FosB/DeltaFosB. CONCLUSIONS: L-DOPA produces pronounced activation of ERK1/2 signaling in the dopamine-denervated striatum through a D1-receptor-dependent mechanism. This effect is associated with the development of dyskinesia. Phosphorylated ERK1/2 is localized to both dynorphinergic and enkephalinergic striatal neurons, suggesting a general role of ERK1/2 as a plasticity molecule during L-DOPA treatment.  相似文献   
979.
Background  Reduced left ventricular ejection fraction (LVEF) is a risk factor for poor outcomes in patients with coronary artery disease (CAD). Mental stress-induced myocardial ischemia (MSIMI) also identifies a subset of CAD patients at increased risk for future cardiovascular events. Susceptibility to MSIMI in patients with CAD and reduced LVEF is unknown. Methods and Results  We enrolled 182 patients (67 women) with a mean age of 64 years and a documented history of CAD in this study. Baseline resting ejection fraction was determined by use of technetium 99m sestamibi gated single photon emission computed tomography. Abnormal LVEF was defined as less than 45% for men and less than 50% for women (based on published norms for our software [Cedars-Sinai Medical Center]). All participants underwent mental stress testing with a public speaking task. Rest/stress myocardial perfusion single photon emission computed tomography was performed via conventional methodology. Images were visually compared for number and severity of perfusion defects by use of a scoring method from 0 to 4. A summed difference score was calculated as the difference between summed stress and rest scores. A score of greater than 3 was considered abnormal. MSIMI developed in 19% of patients with normal LVEF and 31% of those with reduced LVEF. There is no statistically significant difference between the two groups (P=.11). Conclusions  CAD patients with left ventricular dysfunction are equally susceptible to MSIMI as those with normal LVEF. This study was supported by grants HL 070265 and HL 072059 from the National Heart. Lung, and Blood Institute. This material is also the result of work supported by resources and with the use of facilities at the Department of Veterans. Affairs Medical Center, Gainesville, Fla.  相似文献   
980.
BACKGROUND: Long-term intra-oesophageal acid suppression with proton pump inhibitors represents a management option for Barrett's oesophagus and severe reflux oesophagitis, but its stability over time has not been adequately assessed. AIM: Our aim was to evaluate prospectively the efficacy of proton pump inhibitors in suppressing intra-oesophageal acidity after 2-year continuous treatment. METHODS: Forty-five patients with Barrett's oesophagus or severe reflux oesophagitis on a proton pump inhibitor regimen (once or twice daily) that normalised the total percentage acid exposure time were re-evaluated by means of 24-h oesophageal pH-monitoring after 2-year of continuous unmodified treatment. RESULTS: A significant rise in the total percentage acid exposure time was observed at 2-year follow-up (P=0.029), owing to an increased value in 27 (60%) cases (9 on a twice daily regimen), higher than normal in 10 of them (22% of the whole group) (3 on a twice daily regimen). In 18 patients (40%) the total percentage acid exposure time was stable or decreased. Heartburn remained efficiently suppressed in all patients. CONCLUSIONS: The efficacy of proton pump inhibitors in suppressing intra-oesophageal acidity during continuous treatment may decrease over time, up to abnormal levels of oesophageal acid exposure in a minority of cases. This may occur without heartburn recurrence and with both once and twice daily regimens.  相似文献   
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