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71.
Use of a corrected standardized uptake value based on the lesion size on CT permits accurate characterization of lung nodules on FDG-PET 总被引:8,自引:4,他引:8
Hickeson M Yun M Matthies A Zhuang H Adam LE Lacorte L Alavi A 《European journal of nuclear medicine and molecular imaging》2002,29(12):1639-1647
The purpose of this study was to determine the actual standardized uptake value (SUV) by using the lesion size from computer tomography (CT) scan to correct for resolution and partial volume effects in positron emission tomography (PET) imaging. This retrospective study included 47 patients with lung lesions seen on CT scan whose diagnoses were confirmed by biopsy or by follow up CT scan when the PET result was considered negative for malignancy. Each lesion's FDG uptake was quantified by the SUV using two methods: by measuring the maximum voxel SUV (maxSUV) and by using the lesion's size on CT to calculate the actual SUV (corSUV). Among small lesions (2.0 cm or smaller on CT scan), ten were benign and 17 were malignant. The average maxSUV was 1.43+/-0.77 and 3.02+/-1.74 for benign and malignant lesions respectively. When using an SUV of 2.0 as the cutoff to differentiate benignity and malignancy, the sensitivity, specificity, and accuracy were 65%, 70%, and 67% respectively. When an SUV of 2.5 was used for cutoff, the sensitivity, specificity, and accuracy were 47%, 80%, and 59% respectively. The average corSUV was 1.65+/-1.09 and 5.28+/-2.71 for benign and malignant lesions respectively. Whether an SUV of either 2.0 or 2.5 was used for cutoff, the sensitivity, specificity, and accuracy remained 94%, 70%, and 85% respectively. The only malignant lesion that was falsely considered benign with both methods was a bronchioalveolar carcinoma which did not reveal any elevated uptake of fluorine-18 fluorodeoxyglucose (FDG). Of the large lesions (more than 2.0 cm and less than 6.0 cm), one was benign and 19 were malignant and the corSUV technique did not significantly change the accuracy. It is concluded that measuring the SUV by using the CT size to correct for resolution and partial volume effects offers potential value in differentiating malignant from benign lesions in this population. This approach appears to improve the accuracy of FDG-PET for optimal characterization of small lung nodules. 相似文献
72.
目的探讨影响自体颅骨修补术后骨吸收的危险因素。方法回顾性分析2001年1月至2012年12月期间经临沂市人民医院神经外科行自体颅骨修补的患者178例,含201块自体骨瓣,根据术后CT特点对骨吸收进行分级,探讨各危险因素与骨吸收分级之间的关系。结果骨吸收分级在性别、修补时间和骨瓣面积间的差异无意义(P0.05),患者平均年龄随骨吸收分级上升呈下降趋势,但骨吸收各分级间的平均年龄之间差异无意义(P0.05)。骨吸收分级与缺损位置有关(P0.05),重度骨吸收多发生于额颞部和颞部。伴有骨折的骨瓣重度骨吸收发生率高于骨瓣完整者(P0.05)。伴发脑积水并行脑室-腹腔分流术的患者与未行脑室-腹腔分流术的患者相比,前者术后骨瓣塌陷的发生率高于后者(P0.05)。结论自体颅骨修补术后骨吸收分级与患者性别、年龄、修补时间和骨瓣面积无关。骨吸收分级与缺损位置有关,重度骨吸收多发生于额颞部和颞部。伴有骨折的骨瓣重度骨吸收发生率高于骨瓣完整者。伴发脑积水并行脑室-腹腔分流术后容易发生骨瓣塌陷。 相似文献
73.
Hydrogen Sulfide Promotes Surface Insertion of Hippocampal AMPA Receptor GluR1 Subunit via Phosphorylating at Serine‐831/Serine‐845 Sites Through a Sulfhydration‐Dependent Mechanism 下载免费PDF全文
74.
Dingding Zhang Wei Wu Huiying Yan Tianwei Jiang Ming Liu Zhuang Yu Hua Li Chunhua Hang 《Neurological sciences》2016,37(2):219-226
A growing body of evidence suggests that inflammation plays a crucial role in cerebral aneurysm initiation, progression, and rupture. High-mobility group box 1 (HMGB1) is a non-histone nuclear protein that can serve as an alarmin to drive the pathogenesis of inflammatory disease. The purpose of this study was to investigate the expression of HMGB1 in the wall of ruptured and unruptured human cerebral aneurysms. Human cerebral aneurysms (25 ruptured and 16 unruptured) were immunohistochemically stained for HMGB1. As controls, four specimens of the middle cerebral arteries obtained at autopsy were also immunostained. Immunofluorescence double staining was used to determine HMGB1 cellular distribution. HMGB1 was nearly undetectable in the controls. All aneurysm tissues stained positive for HMGB1 monoclonal antibody, and expression of HMGB1 was more abundant in ruptured aneurysm tissue than unruptured aneurysms (p < 0.05). Furthermore, the expression of HMGB1 had no correlation with aneurysm size and time resected after the rupture. HMGB1 nuclear immunoreactivity was co-localized with immunoreactivity of CD3 in T lymphocytes, CD20 in B lymphocytes, CD68 in macrophages, α-SMA in smooth muscle cells, and CD31 in endothelial cells. Cytoplasmic HMGB1 localization was also detected in macrophages and T lymphocytes. Taken together, HMGB1 is expressed in the wall of human cerebral aneurysms and is more abundant in ruptured aneurysms than in unruptured ones. These data indicate a possible role of HMGB1 in the pathophysiology of human cerebral aneurysms. 相似文献
75.
目的评估支架辅助弹簧圈栓塞梭形动脉瘤术中及术后24 h内,在标准双抗血小板治疗的基础上,短期应用小剂量替罗非班在降低缺血并发症方面的安全性及有效性。 方法回顾分析我中心2015年1月至2020年12月颅内未破裂梭形动脉瘤接受支架辅助弹簧圈栓塞治疗,并在手术过程中及术后24 h内静脉接受替罗非班(0.1 μg/kg/min)预防血小板聚集的患者资料。记录并分析围手术期并发症,动脉瘤栓塞程度及术后3个月随访时的mRS评分。 结果本研究共纳入38例患者,39枚动脉瘤,动脉瘤平均直径(6.4±2.1)mm。其中,26枚动脉瘤接受了单支架辅助弹簧圈栓塞治疗,13枚动脉瘤接受了双支架辅助弹簧圈栓塞治疗。术后即刻78.9%(30/38)的动脉瘤实现完全栓塞;在26例接受脑血管造影复查的患者中,92.3%(24/26)的患者动脉瘤实现完全闭塞。围手术期缺血并发症发生率为7.9%(3/38);无出血并发症发生。3个月随访的良好预后率为97.4%(37/38) (mRS评分为0~1分)。 结论支架辅助弹簧圈栓塞梭形动脉瘤术中及术后24 h内,静脉加用小剂量替罗非班未增加出血并发症。但是,由于样本量偏少,缺少对比,在降低缺血并发症方面的有效性尚需进一步证实。 相似文献
76.
目的探讨家属心理护理、生活技能培训在长期住院的慢性精神分裂症患者康复治疗中的作用。方法选取有家庭监护条件的长期住院的精神分裂症患者126例,将其随机分为干预组(66例)和对照组(60例)。干预组由心理咨询师对患者家属进行心理护理、生活技能培训,然后对患者实施假出院3个月。对照组患者仍住院治疗。实施前后采用护士用住院患者观察量表(NOS-IE)、自尊量表(SES)进行测试。结果干预后干预组NOSIE及SES评分显著优于对照组(P<0.01,P<0.05)。结论家属心理护理、生活技能培训用于长期住院的慢性精神分裂症患者,可使其社会能力、生活技能提高,激惹、抑郁等消极情绪减少;自尊水平提升。 相似文献
77.
Ⅱ型糖尿病病人围麻醉期胰岛素抵抗临床观察的探讨 总被引:3,自引:3,他引:3
目的 探讨Ⅱ型糖尿病病人围麻醉期胰岛素抵抗变化的机理及影响。方法 Ⅱ型糖尿病和非糖尿病病人各35例,在平衡麻醉下,各20例在麻醉前、手术开始后90min及拔出气管导管后测定血糖、血胰岛素,其中各10例测定红细胞膜胰岛素受体敏感性;另外15例测定葡萄糖代谢率(M值)。结果 Ⅱ型糖尿病病人术中、术后血糖(G)、血胰岛素(I)明显增高,G/I、胰岛素受体亲合力、M值明显降低。结论 在平衡麻醉下,手术使Ⅱ型糖尿病病人胰岛素受体敏感性下降,致使胰岛素抵抗加重,由此Ⅱ型糖尿病病人的葡萄糖利用率明显降低。 相似文献
78.
OBJECTIVE: To analyze the biodistribution of (186)Re-lipiodol (RL) in patients with primary liver cancer (PLC) after hepatic arterial injection in attempt to assess the potential of RL as a radiopharmaceutical for the treatment of PLC. METHODS: RL was synthesized from (186)Rhenium and Lipiodol by a series of physical and chemical procedures. Doses of RL ranged from 1 110 MBq to 2 220 MBq per patient depending on the volume of tumor. Quantitative gamma camera imaging (ECT) and gamma counting of serum and urine were used to obtain data for dosimetry estimation. Serum tumor marker (AFP) level and shrinkage of tumor were used to evaluate the therapeutic efficacy of RL. RESULTS: In the hepatic tumor, RL was selectively retained and radioactivity was very high throughout this study. The ratio of tumor concentration to the normal liver tissue concentration (T/NT ratio) was 10 - 14 at 48 hours after injection of RL. The main side effects of this therapy were transient fever and anorexia. No unacceptable toxicity was observed. In 100% of the patients, the therapy resulted in a significant decrease of AFP level and reduction of tumor volume. CONCLUSION: The biodistribution and imaging results demonstrated RL localized selectively in tumor, and that RL may be a potential internal radiopharmaceutical agent for the treatment of primary liver cancer. 相似文献
79.
目的探讨经皮腔内血管成形结合支架植入术对膝下动脉硬化闭塞症的治疗效果。方法回顾性分析我院2005年10月~2009年5月182例(210条肢体)膝下动脉硬化闭塞症的临床资料,采用常规或内膜下成形技术对狭窄或闭塞性病变进行球囊扩张,38条肢体在胫腓干植入冠脉支架。结果 195条肢体获得影像学成功(残余狭窄率〈30%),技术成功率为92.9%(195/210)。并发症主要有动脉穿孔(3例)、痉挛(4例)、管壁夹层(6例)及穿刺点血肿(5例),给予相应处理后缓解。182例术后肢体疼痛、麻凉感等临床症状均改善,踝/肱指数(AB I)由术前的0.40±0.11增至术后7 d的0.83±0.15(t=33.50,P〈0.0001)。术后6、12个月肢体血流通畅率分别为89.0%(187/210)和73.3%(154/210),术后12个月肢体保全率和存活率分别为91.4%(192/210)、93.3%(196/210)。结论腔内治疗膝下动脉硬化闭塞症的临床成功率高、并发症少、保肢率高,是安全有效的治疗方法。 相似文献
80.
Cartilage‐Specific Autophagy Deficiency Promotes ER Stress and Impairs Chondrogenesis in PERK‐ATF4‐CHOP–Dependent Manner 下载免费PDF全文
Dongxu Feng Xinxin Jin Zhengmin Ma Zhuang Qian Tianping Xie Huixia Li Jiali Liu Ruiqi Wang Fang Li Danhui Li Hongzhi Sun Shufang Wu 《Journal of bone and mineral research》2017,32(10):2128-2141
Autophagy is activated during nutritionally depleted or hypoxic conditions to facilitate cell survival. Because growth plate is an avascular and hypoxic tissue, autophagy may have a crucial role during chondrogenesis; however, the functional role and underlying mechanism of autophagy in regulation of growth plate remains elusive. In this study, we generated TamCartAtg7–/– (Atg7cKO) mice to explore the role of autophagy during endochondral ossification. Atg7cKO mice exhibited growth retardation associated with reduced chondrocyte proliferation and differentiation, and increased chondrocyte apoptosis. Meanwhile, we observed that Atg7 ablation mainly induced the PERK‐ATF4‐CHOP axis of the endoplasmic reticulum (ER) stress response in growth plate chondrocytes. Although Atg7 ablation induced ER stress in growth plate chondrocytes, the addition of phenylbutyric acid (PBA), a chemical chaperone known to attenuate ER stress, partly neutralized such effects of Atg7 ablation on longitudinal bone growth, indicating the causative interaction between autophagy and ER stress in growth plate. Consistent with these findings in vivo, we also observed that Atg7 ablation in cultured chondrocytes resulted in defective autophagy, elevated ER stress, decreased chondrocytes proliferation, impaired expression of col10a1, MMP13, and VEGFA for chondrocyte differentiation, and increased chondrocyte apoptosis, while such effects were partly nullified by reduction of ER stress with PBA. In addition, Atg7 ablation‐mediated impaired chondrocyte function (chondrocyte proliferation, differentiation, and apoptosis) was partly reversed in CHOP–/– cells, indicating the causative role of the PERK‐ATF4‐CHOP axis of the ER stress response in the action of autophagy deficiency in chondrocytes. In conclusion, our findings indicate that autophagy deficiency may trigger ER stress in growth plate chondrocytes and contribute to growth retardation, thus implicating autophagy as an important regulator during chondrogenesis and providing new insights into the clinical potential of autophagy in cartilage homeostasis. © 2017 American Society for Bone and Mineral Research. 相似文献