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81.
背景和目的:最近的研究结果表明,对其他一线药物和注射类药物(如卡那霉素、卷曲霉素)等耐药是影响耐多药结核病(MDR-TB)患者治疗效果的独立危险因素.本研究旨在明确耐其他一线药物和注射类药物对韩国不合并人免疫缺陷病毒(HIV)感染的MDR-TB患者临床疗效的影响.方法:采用回顾性队列研究分析1996年1月至2005年12月首尔国家大学附属医院治疗的211例MDR-TB患者治疗效果,排除7例丢失和7例迁出,对197例患者进行了最终分析.  相似文献   
82.
Although adjuvant tegafur/uracil (UFT) is recommended for patients with completely resected stage I non‐small‐cell lung cancer (NSCLC) in Japan, only one‐third of cases has received adjuvant chemotherapy (ADJ) according to real‐world data. Therefore, robust predictive biomarkers for selecting ADJ or observation (OBS) without ADJ are needed. Patients who underwent complete resection of stage I lung adenocarcinoma with or without adjuvant UFT were enrolled. The status of ACTN4 gene amplification was analyzed by FISH. Statistical analyses to determine whether the status of ACTN4 gene amplification affected recurrence‐free survival (RFS) were carried out. Formalin‐fixed, paraffin‐embedded samples from 1136 lung adenocarcinomas were submitted for analysis of ACTN4 gene amplification. Ninety‐nine (8.9%) of 1114 cases were positive for ACTN4 gene amplification. In the subgroup analysis of patients aged 65 years or older, the ADJ group had better RFS than the OBS group in the ACTN4‐positive cohort (hazard ratio [HR], 0.084, 95% confidence interval [CI], 0.009‐0.806; P = .032). The difference in RFS between the ADJ group and the OBS group was not significant in ACTN4‐negative cases (all ages: HR, 1.214; 95% CI, 0.848‐1.738; P = .289). Analyses of ACTN4 gene amplification contributed to the decision regarding postoperative ADJ for stage I lung adenocarcinomas, preventing recurrence, improving the quality of medical care, preventing the unnecessary side‐effects of ADJ, and saving medical costs.  相似文献   
83.

Objectives

Digital subtraction radiography (DSR) is a suitable technique for detecting incipient bone changes. However, in DSR, one or more follow-up radiographs must be taken. The aim of this study was to assess the possibility of reducing the exposure time for the radiographs that follow the initial one.

Methods

Maxillary premolar and molar radiographic images of a dry skull were taken with a digital radiography system. The initial radiographs, without bone chips, were taken at 0.32 and 0.16 s. Then, five bone chips (weight range 7–15 mg) were placed on the maxillary molar buccal side of the dry skull. Secondary radiographs were taken at 0.32-, 0.16-, 0.08-, 0.04-, and 0.02-s exposure times. For each bone chip, radiographs were taken three times. The secondary and initial images were subtracted to yield subtraction images. Four observers were asked to evaluate bone change visibility in the subtraction images. The Friedman test was used for statistical analysis.

Results

Significant differences were seen at each of the settings for the 0.32-s group (p = 1.24e?030) and 0.16-s group (p = 7.52e?009). By comparing the different groups, observer evaluations indicated that visibility changed when the secondary radiograph was taken at 1/8 of the exposure time of the initial radiograph. In both groups, the visibility of the 0.02-s subtraction image was significantly lower than that of the other subtraction images.

Conclusion

In DSR, the exposure time of the secondary radiograph can be reduced to 1/4 of the exposure time of the initial radiograph.  相似文献   
84.
抛光过程中复合树脂表面粗糙和光泽度的变化   总被引:2,自引:0,他引:2  
目的探讨抛光过程中复合树脂表面粗糙度和光泽度的变化规律。方法测定9种复合树脂抛光前的压接面及经过240目、320目、400目、600目、800目、1200目金刚砂纸抛光后抛光面的粗糙度值和光泽度值。结果随着由粗至细逐级抛光,粗糙度值稳步下降,至800目时均恢复至抛光前的程度;而光泽度值在600目以前变化甚微,800目时骤然回升,至1200目时有5种树脂已达到或超过抛光前的水平。结论复合树脂必须抛光至一定精细程度,才能获得理想的滑泽表面。  相似文献   
85.
86.
Primary clear cell adenocarcinoma (CCA) of the colorectum is a rare tumor. We report on a 48-year-old man with early stage CCA in the descending colon who underwent detailed examination with image-enhanced endoscopy, such as magnifying endoscopy with narrow-band imaging and crystal violet staining. The tumor was treated successfully with endoscopic mucosal resection at our hospital.  相似文献   
87.
Strain‐dependent induction of allergic rhinitis without adjuvant in mice   总被引:1,自引:0,他引:1  
BACKGROUND: To date, no murine models have been reported to show the induction of both antigen-specific IgE and nasal eosinophilia, two of the major hallmarks of allergic rhinitis, after local sensitization in the absence of adjuvants, a phenomenon which reflects natural exposure. In this report, we attempted to establish a murine model representing an initiation of allergic rhinitis. METHODS: BALB/c, CBA/J, and C57BL/6 mice were sensitized intranasally to Schistosoma mansoni egg antigen (SEA) solely. After repeated sensitization, serum Ab titers, nasal eosinophilia, and cytokine production by nasal lymphocytes were determined. RESULTS: BALB/c mice produced SEA-specific IgE after repeated sensitization. High-dose sensitization to SEA induced IgE production in CBA/J mice, while C57BL/6 mice did not show the production throughout the period observed, suggesting that IgE production was regulated genetically. BALB/c mice also exhibited nasal eosinophilia after the nasal challenge. In addition, nasal lymphocytes sensitized with SEA intranasally produced significant amount of IL-5 in vitro. CONCLUSIONS: These results suggest that intranasal sensitization with SEA in the absence of adjuvants induces a Th2 immune reaction, reflecting the hallmarks of the initiation of allergic rhinitis both in vivo and in vitro, which is genetically regulated.  相似文献   
88.
The influence of forskolin, an adenylate cyclase activator, and of dibutyryl cyclic AMP (Bt2cAMP) on [3H]glycerol incorporation into glycerolipids was investigated in human platelets. It was found that preincubation with 2.5 mM Bt2cAMP produced a 2-4-fold increase in thrombin-induced incorporation into phospholipids compared to platelets activated by thrombin alone. Pretreatment with forskolin, which increased cellular cAMP content, also resulted in an increase in thrombin-stimulated [3H]glycerol incorporation into phospholipids. These findings demonstrate that a rise in platelet cAMP can accentuate thrombin-induced de novo synthesis of phospholipids from [3H]glycerol. Since the content of cellular cAMP was correlated with its ability to inhibit platelet activation monitored by serotonin release, it seems likely that glycerolipid, in particular phospholipid biosynthesis, is involved in controlling platelet activation by thrombin.  相似文献   
89.
A 45 year old Japanese woman with an aneurysm of the left aortic sinus is described. The main trunk of the left coronary artery was displaced upward, and the proximal portion of the circumflex branch was markedly compressed and displaced posteriorly, causing subendocardial infarction and angina. The diagnosis of Takayasu's arteritis was made based on: 1) age, sex and nationality of the patient; 2) inflammatory signs followed by weakness of the right radial pulse; and 3) typical angiographic findings. Five previously reported cases are reviewed.  相似文献   
90.
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