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101.
目的:探讨缺氧缺血性脑损伤(H IBD)后脑内负责葡萄糖转运的两个重要蛋白质葡萄糖转运蛋白-1(GLUT-1)与葡萄糖转运蛋白-3(GLUT-3)表达的变化,揭示H IBD后脑内能量衰竭的发病机制。方法:将30只7日龄W istar大鼠随机分为正常对照组(n=5)、假手术对照组(n=5)和H IBD组(n=20)。H IBD组大鼠模型的制备参照R ice。方法结扎右侧颈总动脉后8%低氧暴露1 h。假手术对照组只分离右侧颈动脉,不予结扎和缺氧。缺氧缺血后1,3,5,10 d各处死5只H IBD大鼠,免疫组化方法检测大鼠脑内GLUT1及GLUT3表达,并与对照组和假手术组比较。结果:正常新生大鼠脑内微血管即可见GLUT1表达。H IBD后1 d,缺血侧半球GLUT1表达略有增加,3 d达高峰,至5 d时仍高于正常,10 d基本恢复正常水平。H IBD后1 d,GLUT3表达无明显变化,3 d时GLUT3表达已明显减少,5 d时进一步减少,10 d时仍显著低于对照组。GLUT3表达减少最显著的部位为海马CA1区。结论:H IBD后脑内GLUT1和GLUT3的表达异常可导致脑能量代谢途径改变,加重缺氧缺血后神经元的损伤及影响损伤神经元的修复。  相似文献   
102.
Background: Previous studies have demonstrated the lifesaving role of an implantable cardioverter-defibrillator (ICD) in high-risk patients with genetic arrhythmogenic diseases.
Aim: To evaluate the clinical data of patients with hypertrophic cardiomyopathy (HCM), arrhythmogenic right ventricular cardiomyopathy (ARVD/C), idiopathic ventricular arrhythmia (IDIO-VA) including Brugada syndrome, short QT syndrome, and long QT syndrome (LQT) enrolled in the Italian ICD Registry in the years 2001–6.
Methods: The survey collected prospectively clinical data and technical characteristics of ICD implants on the basis of EURID form.
Results: The number of patients was 1,274 in the HCM group, 520 in the ARVD/C group, 460 in the IDIO-VA group, and 245 in the LQT group. Primary prevention involved 29.5% of patients in the HCM group, 15.9% in the ARVD/C group, 16.9% in the IDIO-VA group, and 16.6% in the LQT group, respectively. Ventricular tachycardia and ventricular fibrillation were reported in 49.0% and 24.8% in the HCM group, 72.9% and 20.0% in the ARVD/C group, 48.2% and 42.9% in the IDIO-VA group, and 21.2% and 61.6% in the LQT group, respectively. Single-, dual-, and triple-chamber ICDs were implanted in 41.5%, 47.6%, and 10.9% in the HCM group; 57.9%, 36.7%, and 5.4% in the ARVD/C group; 55.0%, 45.0%, and 0% in the IDIO-VA group; and 57.4%, 42.6%, and 0% in LQT group, respectively.
Conclusion: ICD therapies in the years 2001–6 for patients with inherited arrhythmia syndromes were utilized in Italy in a still-limited number of patients. Secondary prevention represented the major indication for ICD implant and the majority of patients were treated by single-chamber ICDs.  相似文献   
103.
PURPOSE: After transurethral resection, we compared the efficacy and side effects of weekly intravesical instillations of epirubicin, bacillus Calmette-Guerin (BCG), and BCG plus isoniazid during a 6-week interval followed by 3 weekly maintenance instillations at months 3, 6, 12, 18, 24, 30 and 36 in patients with intermediate and high risk Ta, T1 bladder cancer. MATERIALS AND METHODS: A total of 957 patients were randomized at 44 institutions in a phase III multicenter trial. RESULTS: The time to first recurrence was significantly longer in patients treated with BCG and BCG plus isoniazid compared to epirubicin (p = 0.0001) but there was no difference between the 2 BCG regimens (p = 0.27). Progression to muscle invasive cancer was rare (5%) and did not differ significantly among the 3 arms (p = 0.12). Drug induced cystitis was observed in 31% of the patients treated with epirubicin, 42% BCG and 45% BCG plus isoniazid. Systemic side effects, such as fever and malaise, were not observed in patients treated with epirubicin, but were noted in 31% BCG and 36% BCG plus isoniazid. CONCLUSIONS: Intravesical BCG with or without isoniazid provokes more side effects than epirubicin. Prophylactic isoniazid does not reduce the side effects of BCG, while BCG with or without isoniazid prolongs the time to first recurrence compared to epirubicin. Further followup is required before long-term conclusions can be made for progression-to-muscle invasive disease and survival.  相似文献   
104.
105.
The role of brain catecholamine (CA) activity in the neuroendocrine regulation of the GnRH-LH system in polycystic ovary syndrome (PCO) was investigated by high-performance liquid chromatography (HPLC) with electrochemical detector. We measured urinary dopamine (DA), noradrenaline (NA), adrenaline (A), vanillylmandelic acid (VMA), homovanillic acid (HVA), 3,4-dihydroxyphenylacetic acid (DOPAC) and total 3-methoxy-4-hydroxyphenylglycol (MHPG) levels in a group of 12 women with PCO before and during peripheral dopa-decarboxylase blockade, by carbidopa. HVA and DOPAC concentrations were significantly lower (P less than 0.001 and P less than 0.005, respectively) in PCO patients compared with twelve control subjects in early follicular phase, whereas total MHPG concentrations and MHPG/VMA ratio were significantly higher (P less than 0.005) in PCO patients. Moreover, HVA and DOPAC concentrations in PCO patients were similar to those of the control subjects in preovulatory phase, while MHPG concentrations remained higher in PCO patients (P less than 0.01). DA, NA, A and VMA concentrations were similar to those of control subjects in both phases of the cycle. During carbidopa administration the concentrations of all urinary CAs and metabolites were unchanged, except those of DA which dropped markedly (P less than 0.001). These data suggest that (1) an altered central catecholamine metabolism consisting of DA deficiency and NA excess is present in PCO, and (2) the site of DA deficiency may be located in the hypothalamus.  相似文献   
106.
We report an improvement in symptoms of heart failure, a reduced left ventricular dysfunction and induced reverse remodelling in one patient with Myotonic Dystrophy type 1, showing an early onset ventricular dysfunction secondary to a complete left bundle branch block (LBBB) who underwent cardioverter defibrillator CRT (ICD- CRT) implantation.Key words: myotonic dystrophy, cardiac resynchronization therapy, sudden death  相似文献   
107.
Flecainide Test in Brugada Syndrome: A Reproducible but Risky Tool   总被引:5,自引:0,他引:5  
GASPARINI, M., et al .: Flecainide Test in Brugada Syndrome: A Reproducible but Risky Tool. The flecainide test is widely used in Brugada syndrome. However, its reproducibility and safety remain ill-defined. This study included 22 patients (18 men, mean age 34 years). Mutations in the SCN5A gene were found in eight patients. Two patients had aborted sudden cardiac death, 8 had syncope/presyncope, and 12 were asymptomatic. The ECG was diagnostic in 19 patients and suggestive in 3. At baseline, 21 of 22 patients underwent a flecainide test (2 mg/kg IV bolus over 10 minutes). In 21 of 21 patients the test was diagnostic or amplified the typical ECG pattern. At the end of drug infusion, sustained VT lasting 7–10 minutes developed in two patients. A second flecainide test was performed within 2 months in 20 patients. The test was not repeated in the two patients with prior development of VT. The flecainide test was diagnostic in 20 of 20 patients. Sustained VT occurred in one patient and recurrent VF in another. The reproducibility of the flecainide test was 100%. In 4 (18%) of 22 patients major VAs were documented after the end of flecainide infusion. VA occurred in 3 (43%) of 7 patients with, versus 1 (7%) 15 without SCN5A gene mutation (P < 0.05). No diagnostic ECG changes or arrhythmias developed in 25 control patients without structural heart disease who underwent the same study protocol. This study shows a high flecainide reproducibility, supporting its diagnostic value in Brugada syndrome. However, the occurrence of major VA, significantly higher in patients with documented SCN5A gene mutation, including in asymptomatic patients, mandates the performance under appropriate medical supervision. Whether a slower rate of drug infusion can lower the risk of VA induction, while maintaining the sensitivity of the test should be explored. (PACE 2003; 26[Pt. II]:338–341)  相似文献   
108.
ROLE OF ALCOHOLIC BEVERAGES IN ESSENTIAL HYPERTENSIVE PATIENTS   总被引:1,自引:0,他引:1  
To evaluate the importance of alcohol and other environmentalfactors in essential hypertensives, we conducted a cross-sectionalstudy on 627 patients (322 women, 305 men) subdivided in foursubgroups according to sex and presence or absence of drug therapy,to evaluate differences due to drugs and changes in life style.Multiple regression analyses were run where systolic and diastolicblood pressures were considered as separate dependent variableswith the following independent variables: age, body mass index,physical activity, alcohol and coffee consumption, smoking,educational level; considered as continuous or categorical variables.Eighty-eight per cent of all patients showed a moderate-lowalcohol intake (1–50 g/day); wine was the preferred beverage.We found a negative independent relationship between mild/moderatealcohol consumption levels and systolic blood pressure in untreatedmen and untreated women, and no relationship between alcoholand diastolic blood pressure in all subgroups considered. Bodymass index and age were positively associated with both systolicand diastolic blood pressure. Our data suggest that mild tomoderate alcohol consumption does not affect blood pressurecontrol in either treated or untreated hypertensive patients.  相似文献   
109.
Ischaemia and reperfusion phases represent critical events during liver transplantation. The purpose of this study was to describe morphological alterations of both vascular and parenchymal compartments after ischaemia and reperfusion and to evaluate the possible relationship between morphometric parameters and biochemical/clinical data. Three needle biopsies were drawn from 20 patients who underwent orthotopic liver transplantation. The first biopsy was taken before flushing with preservation solution, and the second and the third to evaluate respectively the effects of cold ischaemia and of warm ischaemia/reperfusion. Biopsies were examined by an image analyser and morphometric parameters related to the liver parenchyma were evaluated. At the second biopsy we observed a decrease of the endothelium volume fraction while the same parameter referred to the sinusoidal lumen achieved a peak value. The hepatocytes showed a lower surface parenchymal/vascular sides ratio. This parameter was reversed at the end of the reperfusion phase; furthermore the third biopsy revealed endothelial swelling and a decreased volume fraction of the sinusoidal lumen. The results quantify the damage to the sinusoidal bed which, as already known, is one of the main targets of cold ischaemia; warm ischaemia and reperfusion accentuate endothelial damage. The end of transplantation is characterised by damage chiefly to parenchymal cells. Hepatocytes show a rearrangement of their surface sides, probably related to the alterations of the sinusoidal bed. In addition, the fluctuations of morphometric parameters during ischaemia/reperfusion correlate positively with biochemical data and clinical course of the patients.  相似文献   
110.
Aim of the study: To examine the long-term effects of cardiac resynchronization therapy (CRT) in patients presenting with heart failure (HF) and QRS ≤120 ms.
Methods: This was a prospective, longitudinal study of 376 patients [mean age = 65 years, mean left ventricular (LV) ejection fraction (EF) = 29%, mean QRS duration =165 ms, mean distance covered during a 6-minute hall walk (6-MHW) = 325 m], who underwent successful implantation of CRT systems. The QRS duration at baseline was ≤120 ms in 45 patients (12%) who were not pre-selected by echocardiographic criteria of dyssynchrony, and >120 ms in the remaining 331 patients. The baseline characteristics of the 2 groups were similar. We evaluated indices of cardiac function, percentage of responders, and survival rates over a mean 28-month follow-up.
Results: Both groups experienced similar long-term increases in 6-MHW, and decreases in New York Heart Association functional class and LV end-systolic volume (all comparisons P < 0.0001 in both groups). Time interaction of changes in LVEF and percentage of responders were significantly different (P = 0.03 and P = 0.004, respectively), in favor of the narrow QRS group, where the changes were sustained and persisted at 2 and 3 years. The long-term death rate from HF was lower in the group with narrow than in the group with wide QRS complex (P = 0.04; log-rank test).
Conclusions: CRT confers considerable long-term clinical, functional, and survival benefits in patients presenting with HF and narrow QRS, not preselected by echocardiographic criteria of dyssynchrony. Caution is advised before denying CRT to these patients on the basis of QRS width only.  相似文献   
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