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91.
We report a case, which we believe to be rare, of adenosine-sensitive atrial tachycardia (AT) originating from the mitral valve annulus. The patient, a 73-year-old woman, died of unrelated cause 4 years after radiofrequency (RF) ablation therapy. Histologically, fibrous replacement of atrial musculature by mature collagenous tissue produced by the RF current was observed at the left inferior atrioventricular junction. In serial sections that included the coronary sinus, two distinct nodal structures containing small, pale myocytes within the fibrous tissue matrix were identified around the region of the ablation lesion. Our case appears to be a unique representation of tissue that was associated with the occurrence and maintenance of AT.  相似文献   
92.
Background: Achieving long-term gene expression in kidney will be beneficial for gene therapy of renal and congenital diseases, genetic studies constructing animal disease models, and the functional analysis of disease-related genes.

Purpose: The purpose of this study was to develop an in vivo long-term gene expression system in murine kidney using ?C31 integrase.

Methods: Gene expression in cultured RENCA, TCMK-1, and HEK293 cells was assessed. The long-term in vivo gene expression system in the kidney was achieved by co-transfecting 5?µg of pORF-luc/attB as a donor plasmid and 20?µg of pCMV-luc as a helper plasmid into the right kidney of mice by electroporation. Luciferase expression levels were measured to determine longevity of the expression.

Results: Significantly high luciferase expression levels were observed in cultured RENCA, TCMK-1, and HEK293 cells over 1 month compared with controls (non-integrase system). The luciferase cDNA sequence was integrated at a pseudo attP site termed mpsL1. In vivo luciferase expression levels in the integrase group were sustained and significantly higher than those in the control group over 2 months. Furthermore, ?C31 integrase-transfected cells had less genomic DNA damage caused by integrase expression.

Discussion and conclusion: These results demonstrated that the ?C31 integrase system could produce long-term (2 months) in vivo gene expression in mouse kidney.  相似文献   
93.
BackgroundPreviously, we found that an upward air current in the head area, induced by forced air warming (FAW), was completely counteracted by downward laminar airflow. However, this study did not include any consideration of the air-conditioner outlet layout (ACOL); hence, its impact remains unclear.MethodsThis study was performed in 2 operating rooms (ORs)—ISO classes 5 and 6, which are denoted as OR-5 and OR-6, respectively. Both ORs have distinct ACOLs. The cleanliness, or the number or ratio of shifting artificial particles was evaluated.ResultsDuring the first 5 minutes after particles generation, significantly more particles shifted into the surgical field in OR-5 when compared to OR-6 (13,587 [4,341-15,913] and 106 [41-338] particles/cubic foot, P < .0001). Notably, FAW did not increase the number of shifting particles in OR-6. The laminar airflow system fully counteracted the upward airflow caused by FAW in OR-6, where the ACOL covered the operating bed. However, this did not occur in OR-5, where the ACOL did not fully cover the operating bed.ConclusionsRegardless of cleanliness ability of OR, an ACOL that fully covers the operating bed can prevent upward airflow in the head area and reduce the number of artificial particles shifting into the surgical field, which are typically caused by FAW.  相似文献   
94.
Measles virus was isolated from the middle ear fluid (MEF) of two infant cases of acute otitis media (AOM) associated with measles. This is the first report on the isolation of measles virus from the MEF in patients with AOM, and possibility of the measles virus as a causative agent of AOM was suggested.  相似文献   
95.
Myocardial bridging increases the risk of coronary spasm   总被引:2,自引:0,他引:2  
BACKGROUND: Myocardial bridging (MB) has been associated with cardiac events. Whether coronary spasm is one factor contributing to those events is unknown. HYPOTHESIS: This study investigated whether the likelihood of coronary spasm is increased in patients with MB. METHODS: A spasm-provocation test was performed by infusing acetylcholine into the left coronary artery in 114 Japanese patients with chest pain. The test result was defined as positive when the diameter of the coronary artery was reduced by > or = 50% and ST-segment changes were documented. Myocardial bridging was defined as a > 15% reduction in coronary arterial diameter during systole after intracoronary injection of nitroglycerin. RESULTS: Myocardial bridging was identified in 41 patients (36%) and was located in the mid-segment of the left anterior descending coronary artery (LAD) in all patients. Patients with MB experienced coronary spasm more frequently than patients without MB (MB+: 73%; MB-: 40%, p = 0.0006). Furthermore, among patients with a positive spasm-provocation test, coronary spasm occurred more frequently in the mid-segment of the LAD in patients with MB than in those without MB (MB+: 73%; MB-: 45%, p = 0.0259). Multivariate regression analysis demonstrated that MB was a predictor of coronary spasm (odds ratio: 3.478, p = 0.0088). CONCLUSIONS: These results suggest that MB increases the risk of coronary spasm and that coronary spasm may be the proximate etiology of cardiac events associated with MB.  相似文献   
96.
The amino acid sequences of the Env V3 region of HIV-1 subtype E in Thailand were highly variable in the samples obtained from 1995 to 1997, compared with the previously reported sequences in samples obtained from 1990 to 1993. The sequences of the V3 region in the samples from five provinces in Thailand revealed that the variability was much higher in the samples from Bangkok and Ubonrachathani than in those from Chiangmai, Prathumthani, and Trang. There was no apparently different level of diversity at the V3 region in the samples from symptomatic and asymptomatic individuals. The V3 loop motif in most (66.7%) of the samples was GPGQ, although this motif was more heterogeneous in the samples from Bangkok and Ubonrachathani than in those from the other three provinces. The N-linked glycosylation sites in the V3 region among these samples were relatively conserved. There was no apparent difference in the presence of positively charged amino acids at positions 306 and 320 between the samples from symptomatic and asymptomatic individuals.  相似文献   
97.
A scanning acoustic microscope (SAM) calculates the speed of sound (SOS) through tissues and plots the data on the screen to form images. Hard tissues result in greater SOS; based on these differences in tissue properties regarding SOS, SAM can provide data on tissue elasticity. The present study evaluated whether tissue modifications, such as formalin fixation, periodic acid‐Schiff (PAS) reactions and protein degradation, changed the acoustic properties of the tissues and whether SAM could be a useful tool for following chemical changes in sections. The fixation process was observable by the increased SOS. During the PAS reaction, the glycosylation of tissues was characterized by an increased SOS. Mucous or glycogen distribution was visualized and was found to be statistically comparable among lesions and states. Protease digestion by pepsin led to a decreased SOS. Tissue sensitivity to proteases varied due to the stage, cause and duration of inflammation or ageing. Changes in acoustic properties were more sensitive than those in optical histology. SAM facilitates the visualisation of the time course or distribution of chemical modifications in tissue sections, thus aiding their comparison among tissues. SAM may be an effective tool for studying changes such as protein cross‐linkage, tissue repair and ageing.  相似文献   
98.
Clinical Rheumatology - To evaluate the ability of geldanamycin to modulate two opposing TNFα/TNFR1-triggered signals for inflammation and cell death. The effects of geldanamycin on...  相似文献   
99.
Miliary tuberculosis is a potentially lethal type of tuberculosis that results from the hematogenous dissemination of Mycobacterium tuberculosis bacilli. We herein describe the case of a 34-year-old man that presented with a one-month history of cough and fever, while his sputum smear results were negative. Chest computed tomography revealed bilateral centrilobular ground-glass opacification (GGO), suggestive of hypersensitivity pneumonitis; thus, bronchoscopy was performed. Cryobiopsy specimens revealed necrotic granulomas. A re-examination of sputum after bronchoscopy identified Mycobacterium tuberculosis, and miliary tuberculosis was diagnosed. A cryobiopsy might be useful for diagnosing miliary tuberculosis pathologically, particularly when miliary nodules may be masked by GGO.  相似文献   
100.
A 72-year-old man had undergone uncomplicated endoscopic submucosal dissection (ESD) with en bloc resection of a localized 20-mm IIc lesion in the anterior wall of the gastric angle. Twenty-eight days later, he was re-admitted with epigastric pain of one-week duration. Contrast-enhanced computed tomography (CT) revealed a 60-mm mass bordered by viscera; repeat endoscopy confirmed a smooth elevated submucosal tumor at the greater curvature on the oral side of the post-ESD ulcer. We diagnosed him with a perigastric abscess as a complication of ESD and performed endoscopic ultrasound-guided drainage. Subsequently, the symptoms and blood inflammatory parameters improved, and follow-up CT showed the disappearance of the abscess.  相似文献   
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