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51.
In the past 4 years, 34 asymptomatic patients with the Wolff-Parkinson-White (WPW) pattern underwent electrophysiologic study. The effective refractory period (ERP) of antegrade conduction over the accessory pathway was 288 +/- 29 msec. In three asymptomatic patients (9%), the antegrade ERP of the accessory pathway was shorter than 250 msec. The antegrade ERP of the accessory pathway became shorter than 250 msec in an additional 12 of 22 (55%) patients after isoproterenol administration. Nineteen (56%) of the asymptomatic patients showed the absence of retrograde conduction over the accessory pathway even after isoproterenol administration. The rate of induction of orthodromic reciprocating tachycardia in the asymptomatic WPW patients was 15% (5/34), which was significantly lower than that in the symptomatic patients. These data suggest that in the asymptomatic patients, the absence of retrograde conduction over the accessory pathway is the reason they remained asymptomatic, free of reciprocating tachycardia. However, even in the asymptomatic patients, some had the accessory pathway in which antegrade ERP was shorter than 250 msec. They may result in rapid ventricular conduction over the accessory pathway when atrial fibrillation develops.  相似文献   
52.
Background and objective: The aim of the present study was to examine clinical and other features that might allow prognostic distinctions between histological patterns in presentations with rapidly progressive interstitial pneumonia (RPIP), and to assess prognostic factors for survival. Methods: Patients with RPIP among 425 consecutive patients with diffuse lung disease, who underwent surgical lung biopsy, were studied retrospectively. The discriminatory value of clinical and investigative features for identifying disease with a better outcome was evaluated. An a priori comparison was made between diffuse alveolar damage (DAD)/usual interstitial pneumonia with DAD pattern (Group A), and organizing pneumonia/non‐specific interstitial pneumonia pattern (Group B). Results: Twenty‐eight patients (6.6%) fulfilled the criteria for RPIP. The diagnosis was Group A disease in 15 (DAD in 10, usual interstitial pneumonia with DAD in 5), and Group B disease in 13 (organizing pneumonia in 8, non‐specific interstitial pneumonia in 5). There were no significant differences in initial findings between the groups. Prognosis was significantly better for Group B patients than for Group A patients (P = 0.021). Neither BAL nor parenchymal high‐resolution CT score was indicative of therapeutic responsiveness or outcome. Distinction between Group A and Group B on the basis of disease pattern was the only significant determinant of prognosis. Conclusions: RPIP included varied histological patterns with different outcomes, and in many cases these could not be predicted using baseline clinical data. Histology was the only significant predictor of ultimate prognosis.  相似文献   
53.
Background: Depression may increase the risk of developing Alzheimer's disease (AD). Recent large cohort studies have also shown that a low plasma amyloid β (Aβ)‐42 level combined with a high Aβ40 level increases the risk of developing AD, suggesting plasma Aβ42/40 ratio as useful for identifying risk of developing mild cognitive impairment and AD. Although several studies have examined Aβ levels in the peripheral blood of elderly individuals with depression, results have been inconsistent. Furthermore, no results have been described for younger depression. Methods: Serum Aβ40, Aβ42 level and Aβ40/42 ratio were evaluated using enzyme‐linked immunosorbent assay in 60 patients with major depressive disorder (MDD) and 60 healthy controls. The results were analyzed in two age groups (young, <60 years; elderly, ≥60 years). Results: Serum Aβ40 level was significantly higher in young MDD patients compared to young controls (P < 0.001), but it was not significantly deferent in the elderly group. Serum Aβ42 level did not differ significantly in both young and elderly groups. Aβ40/42 ratio was significantly higher in both young (P < 0.001) and elderly (P < 0.001) patients with MDD compared to controls. Conclusions: Serum Aβ40/42 ratio was significantly higher in MDD patients than in controls, and this difference was seen for both elderly and young subjects. This may suggest that even young subjects with MDD undergo pathological changes in the very early stage of amyloid deposition.  相似文献   
54.
Saw palmetto extract (SPE), an extract from the ripe berries of the American dwarf palm, has been widely used as a therapeutic remedy for urinary dysfunction due to benign prostatic hyperplasia (BPH) in Europe. Numerous mechanisms of action have been proposed for SPE, including the inhibition of 5a-reductase. Today, al-adrenoceptor antagonists and muscarinic cholinoceptor antagonists are commonly used in the treatment of men with voiding symptoms secondary to BPH. The improvement of voiding symptoms in patients taking SPE may arise from its binding to pharmacologically relevant receptors in the lower urinary tract, such as al-adrenoceptors, muscarinic cholinoceptors, 1,4-dihyropyridine receptors and vanilloid receptors. Furthermore, oral administration of SPE has been shown to attenuate the up-regulation of α1-adrenoceptors in the rat prostate induced by testosterone. Thus, SPE at clinically relevant doses may exert a direct effect on the pharmacological receptors in the lower urinary tract, thereby improving urinary dysfunction in patients with BPH and an overactive bladder. SPE does not have interactions with co-administered drugs or serious adverse events in blood biochemical parameters, suggestive of its relative safety, even with long-term intake. Clinical trials (placebo-controlled and active-controlled trials) of SPE conducted in men with BPH were also reviewed. This review should contribute to the understanding of the pharmacological effects of SPE in the treatment of patients with BPH and associated lower urinary tract symptoms (LUTS).  相似文献   
55.
目的辅助性T细胞17(Th17)是-种CD4阳性T细胞新亚群,本研究探讨Th17相关细胞因子与根尖周炎的炎症反应及牙槽骨破坏的关系。方法选取5周龄雄性Wistar大鼠,实验组用球钻将下颌第1磨牙开髓,根管锉清理牙髓,髓腔暴露于口腔中,14d后断颈处死。以未开髓的上颌第1磨牙作为对照组。取上下颌骨,采用Micro—CT观察根尖病损的形成情况;实验组和对照组标本均为6例,标本固定、脱钙,冰冻切片、组织学方法观察根尖病损的特点,采用抗CD68和抗TCRαβ的单克隆抗体进行免疫组化;用酶组织化学染色(TRAP染色)进行破骨细胞染色;实验组和对照组根尖组织提取总RNA,RT-PCR及荧光实时定量PCR方法定量检测根尖组织中Th17相关细胞因子IL-17、IL-23、IL-β、IL-6、TGF—β,以及破骨细胞分化因子RANKL的mRNA表达情况。结果Micro.CT显示,14d实验组有明显的根尖病损形成;组织学结果表明,实验组均存在根尖脓肿,有大量中性粒细胞、CD68阳性的巨噬细胞和散在的TCRctl3阳性T细胞浸润;病损骨面有较多的TRAP阳性破骨细胞,表明有活跃的骨吸收;RT—PCR及实时定量PCR结果显示,实验组根尖组织中Th17相关细胞因子IL-17、IL-23、IL1β、IL-6,及破骨细胞分化因子RANKL的mRNA均显著高于对照组,而TGF-β无显著性变化。结论Th17相关细胞因子在实验性根尖周炎中均有高表达,提示它们可能参与炎症过程和骨破坏。  相似文献   
56.
IntroductionIt has been well known that physical inactivity is associated with a significantly higher incidence of coronary artery disease. This study aimed to test our hypothesis that endurance aerobic exercise training has cardiovascular protective effects as a result of inhibiting inflammatory processes.MethodsForty-two overweight women [age, 53.4 ± 9.8 years; body mass index (BMI), 28.0 ± 2.8] received electric bicycle ergometer exercise therapy at the lactate threshold intensity for 30 to 60 minutes per day, 1 to 6 times per week for 6 weeks. The exercise training was performed within the possible load (exercise duration and frequency) for each subject.ResultsLeukocyte, monocyte, and neutrophil counts significantly decreased after the exercise therapy (P < 0.05). In simple regression analysis, percent changes in monocyte and neutrophil counts were correlated with percent changes in fasting triglyceride levels, insulin sensitivity index, BMI, and maximal oxygen uptake (VO2max). In stepwise multiple regression analysis, the percent change in monocyte counts was associated with percent changes in fasting triglyceride and VO2max (r2 = 0.368, P < 0.001), and the percent change in neutrophil counts was associated with percent changes in insulin sensitivity index and BMI (r2 = 0.292, P < 0.001).ConclusionsEndurance aerobic exercise training can influence some inflammatory processes. Furthermore, increased aerobic capacity may be antiinflammatory and have cardiovascular protective effects in overweight women.  相似文献   
57.
Summary. Background: Activated protein C (APC) can regulate immune and inflammatory responses and apoptosis. Protein C transgenic mice develop less diabetic nephropathy but whether exogenous administration of APC suppresses established diabetic nephropathy is unknown. Objectives: We investigated the therapeutic potential of APC in mice with streptozotocin‐induced diabetic nephropathy. Methods: Diabetes was induced in unilaterally nephrectomized C57/Bl6 mice using intraperitoneal (i.p.) injection of streptozotocin. Four weeks later, the mice were treated with i.p. exogenous APC every other day for 1 month. Results: APC‐treated mice had a significantly improved blood nitrogen urea‐to‐creatinine ratio, urine total protein to creatinine ratio and proteinuria, and had significantly less renal fibrosis as measured by the levels of collagen and hydroxyproline. The renal tissue concentration of monocyte chemoattractant protein‐1 (MCP‐1), vascular endothelial growth factor (VEGF) and the RNA expression of platelet‐derived growth factor (PDGF), transforming growth factor‐β1 and connective tissue growth factor (CTGF) were significantly lower in APC‐treated mice than in untreated animals. The percentage of apoptotic cells was reduced and the expression of podocin, nephrin and WT‐1 in the glomeruli was significantly improved in mice treated with APC compared with untreated mice. The levels of coagulation markers were not affected by APC treatment. Conclusion: Exogenous APC improves renal function and mitigates pathological changes in mice with diabetic nephropathy by suppressing the expression of fibrogenic cytokines, growth factors and apoptosis, suggesting its potential usefulness for the therapy of this disease.  相似文献   
58.
Bestrabucil (KM2210), the benzoate of an estradiol-chlorambucilconjugate, was used experimental cancer chemotherapy against13 human tumor xenografts serially transplanted into nude mice,and its pharmacokinetics was studied. The tumors were one esophageal,two gastric, six colon, one cholecystic and three breast carcinomas.Two tumor tissue fragments approximately 3x3x3 mm were inoculatedinto BALB/cA nude mice, which were then treated with KM2210at doses of 100, 200 and 300 mg/Kg/day orally starting 24 hrafter the transplantation or when the tumor reached a weightof 100–300 mg. The concentration of KM2210 and its derivativesin the tumor xenografts, normal muscular tissue and blood wereassayed by high performance liquid chroma-tography. Six out of 13 xenografts were found to be sensitive to KM2210.The concentrations of KM2210 and its derivatives in the tumortissues of the sensitive xenografts were five to 10 times higherthan those in blood and muscular tissue, and the antitumor activitycorrelated well with the area under the curve of active metabolitesof KM2210 in the tumor.  相似文献   
59.
Small renal oncocytoma with central cystic degeneration   总被引:4,自引:0,他引:4  
A case of a small renal oncocytoma with central cystic degeneration, 15 mm in diameter, is reported. Contrast-enhanced computed tomography showed the tumor contained a central hypoattenuating region and had an irregular, heterogeneously enhanced wall. Magnetic resonance images showed a well-circumscribed lesion and the T(1)-weighted image indicated medium signal intensity, whereas the T(2)-weighted image indicated slight hypointensity. Both T(1)- and T(2)-weighted images showed central hyperintensity. Our preoperative diagnosis was renal cell carcinoma originating in a renal cyst wall or cystic renal cell carcinoma. Nephrectomy was performed because frozen-section examination did not completely rule out malignancy. The final pathological diagnosis of the entire surgical specimen was renal oncocytoma with cystic degeneration. To our knowledge, this is the 14th case of renal oncocytoma with central cystic degeneration reported in the published works. We discuss herein the variant forms of oncocytoma and difficulties with their preoperative diagnosis, especially when the tumor is small.  相似文献   
60.
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