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71.
The beta-adrenoceptor (beta-AR)-stimulatory guanine nucleotide-binding (Gs) protein system has been shown to play important roles in the cardiovascular system. The gene encoding the alpha-subunit of Gs proteins (GNAS1) is a candidate genetic determinant for hypertension. Because alcohol consumption is known to affect blood pressure partly through the beta-AR-Gs protein system, we examined the possible interaction between GNAS1 T393C polymorphism and drinking status in the association with hypertension in the present study. As a result, a non-significant but reasonable trend supporting the presence of an interaction was shown (p = 0.076). In line with this trend, the T393C polymorphism significantly interacted with drinking status in the association with systolic blood pressure (p = 0.028). Moreover, supporting the presence of an interaction, T allele carriers consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than CC homozygotes in non-drinkers and light drinkers. In contrast, CC homozygotes consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than T allele carriers in moderate to heavy drinkers. The present study also showed a significant interaction between the T393C polymorphism and drinking status in the association with pulse pressure (p = 0.026), reflected by a significant association between the T393C polymorphism and pulse pressure in moderate to heavy drinkers (p = 0.026). These findings may be helpful in conducting further molecular and biological studies on the relationship among the effects of alcohol, the beta-AR-Gs protein system, and hypertension.  相似文献   
72.
EP News     
Peng-Sheng Chen MD   《Heart rhythm》2006,3(2):249-250
  相似文献   
73.
Amyloidosis is a systemic disease that usually occurs in the gastrointestinal tract or in muscular or adipose tissue. Primary amyloidosis of the urinary bladder is a rare disease that can mimic bladder cancer on cystoscopic examination as well as in its clinical presentation of painless gross hematuria. This report describes a 49-year-old male with repeated painless gross hematuria, who underwent transurethral resection of a suspected bladder tumor. Pathologic examination revealed papillary urothelial hyperplasia with vascular ectasia and no signs of malignancy. Massive gross hematuria occurred 2.5 years later. Cystoscopy showed multiple papillary lesions with yellowish-brown submucosal plaques on the posterior bladder wall. A second transurethral tumor resection was performed and histologic examination revealed plasma cell infiltration and eosinophilic amorphous deposits in the subepithelial stroma and vascular wall. The deposits were positive for Congo red and apple-green birefringence under polarized light examination but negative for Masson's trichrome stain, indicating that they were not fibrotic in nature. Hence, the diagnosis of amyloidosis of the urinary bladder was confirmed. Screening for amyloidosis was negative in other organ systems and the patient has remained disease-free up to the last follow-up 4 years after the second transurethral resection. Amyloidosis should be considered in the differential diagnosis of patients with recurrent hematuria who have symptoms characteristic of bladder cancer but negative pathologic study for malignancy. Correct diagnosis relies on clinical alertness and the use of a special staining technique during pathologic examination.  相似文献   
74.
目的探讨用游离自体腹白线片修补急性十二指肠溃疡穿孔的应用价值。方法从2006年1月至2006年7月对13例用自体腹白线片修补急性十二指肠溃疡穿孔的病人的临床资料和随访情况进行回顾性分析,其中2例穿孔大于2cm2,平均手术时间60分钟,平均失血量20ml,平均住院天数9±1天。结果游离自体腹白线片修补急性十二指肠溃疡穿孔13例均痊愈出院。随访15天至6个月,无手术并发症。结论本方法操作较简单、安全、效果好,其适应症广,是一种可行的新方法。  相似文献   
75.
多发性硬化患者血清尿酸水平变化的研究   总被引:2,自引:0,他引:2  
目的 探讨多发性硬化 (MS)患者血清尿酸 (UA)水平的变化及其临床意义。方法 采用酶定量分析法对 4 3例MS患者和 4 5名正常对照者的血清UA水平进行检测。结果 MS组血清UA水平明显低于对照组 (P <0 0 1)。MS组中病程越长 (P <0 0 1)、神经伤残程度越重 (DSS评分越高 ) (P <0 0 5 ) ,血清UA水平越低 ;女性患者UA水平明显低于男性患者 (P <0 0 0 1) ;经过糖皮质激素治疗后血清UA水平明显回升 (P <0 0 0 1) ,但治疗前血清UA水平越低则疗效越差 (P <0 0 1、P <0 0 5 )。结论 MS患者血清UA水平降低 ,且与MS的病程、伤残程度、疗效及性别密切相关。UA水平升高可能为激素治疗MS的一个作用机制  相似文献   
76.
Bone marrow stromal cells (MSCs) increase vascular endothelial growth factor (VEGF) expression and promote angiogenesis after stroke. Angiopoietin-1 (Ang1) and its receptor Tie2 mediate vascular integrity and angiogenesis as does VEGF and its receptors. In this study, we tested whether MSC treatment of stroke increases Ang1/Tie2 expression, and whether Ang1/Tie2 with VEGF/ vascular endothelial growth factor receptor 2 (VEGFR2) (Flk1), in combination, induced by MSCs enhances angiogenesis and vascular integrity. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAo) and treated with or without MSCs. Marrow stromal cell treatment significantly decreased blood-brain barrier (BBB) leakage and increased Ang1, Tie2, and occludin (a tight junction protein) expression in the ischemic border compared with MCAo control. To further test the mechanisms of MSC-induced angiogenesis and vascular stabilization, cocultures of MSCs with mouse brain endothelial cells (MBECs) or astrocytes were performed. Supernatant derived from MSCs cocultured with MBECs significantly increased MBEC expression of Ang1/Tie2 and Flk1 compared with MBEC alone. Marrow stromal cells cocultured with astrocytes also significantly increased astrocyte VEGF and Ang1/Tie2 expression compared with astrocyte culture alone. Conditioned media from MSCs alone, and media from cocultures of MSCs with astrocytes or MBECs, all significantly increased capillary tube-like formation of MBEC compared with control Dulbecco's modified Eagle's medium media. Inhibition of Flk1 and/or Ang1 significantly decreased MSC-induced MBEC tube formation. Knockdown of Tie2 expression in MBECs significantly inhibited MSC-induced tube formation. Our data indicate MSC treatment of stroke promotes angiogenesis and vascular stabilization, which is at least partially mediated by VEGF/Flk1 and Ang1/Tie2.  相似文献   
77.
To extend the signal longevity of magnetically excited spins in flowing fluids while in a state of global coherent free precession (GCFP), a refocusing radiofrequency (RF) pulse and bipolar gradient waveforms were combined with the GCFP sequence. The data demonstrate that RF refocusing in the presence of flowing blood is possible, but the improvement in signal amplitude depends on the static magnetic field homogeneity along the direction of motion and the displacement of the spins between the excitation and the RF refocusing pulse, as well as displacement during subsequent RF refocusing pulses. The least amount of phase dispersion and thus the longest lasting signal is obtained with the shortest echo spacing where only one line of data is recorded between two RF refocusing pulses. This approach was successfully used in a phantom and in vivo to image fast and slow blood flow. Depending on the experimental conditions, signal persistence is improved significantly compared to playing the same sequence without RF refocusing, but the improvement is limited by the product of blood flow velocity and the time between RF refocusing pulses.  相似文献   
78.
We report a rare chronic encapsulated intracerebral haematoma (CEICH). A 52-year-old man had two seizures. Unenhanced computed tomography scanning of the head revealed a hypodense tumour with clusters of calcification in the left temporal lobe. Magnetic resonance imaging of the brain showed a left temporal tumour with a hypointense centre and hyperintense periphery on T(1)-weighted imaging and heterogeneous hypointensity on T(2)-weighted imaging. The tumour was heterogeneously enhanced after gadolinium injection. Craniotomy was carried out and a CEICH in the left temporal lobe was completely excised. No vascular anomaly was found. The tumour was histologically confirmed to be a CEICH. The patient recovered well after the operation. In this report, we describe this rare case and discuss the characteristics of CEICH.  相似文献   
79.
The mechanisms underlying neurologic deficits and delayed neuronal death after ischemia are not fully understood. In the present study, we report that transient cerebral ischemia induces accumulation of ubiquitinated proteins (ubi-proteins) in postsynaptic densities (PSDs). By immunoelectron microscopy, we demonstrated that ubi-proteins were highly accumulated in PSD structures after ischemia. On Western blots, ubi-proteins were markedly increased in purified PSDs at 30 minutes of reperfusion, and the increase persisted until cell death in the CA1 region after ischemia. In the resistant DG area, however, the changes were transient and significantly less pronounced. Deposition of ubi-proteins in PSDs after ischemia correlates well with PSD structural damage in the CA1 region as viewed by electron microscopy. These results suggest that the ubiquitin-proteasome system fails to repair and remove damaged proteins in PSDs. The changes may demolish synaptic neurotransmission, contribute to neurologic deficits, and eventually lead to delayed neuronal death after transient cerebral ischemia.  相似文献   
80.
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