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71.
梁畅  张伟 《现代肿瘤医学》2020,(11):1958-1962
我国乳腺癌的发病率占女性恶性肿瘤疾病的首位,结构扭曲病变(architectural distortion,AD)作为触诊阴性乳腺癌的第三最常见影像学表现,也是乳腺癌最早出现的征象,具有重要的临床价值。AD具有较高的漏诊率及假阳性率。本文通过查阅文献,针对超声、乳腺X线摄影、乳腺数字三维断层摄影技术及核磁共振成像技术在乳腺结构扭曲病变中的研究进展及优缺点进行分析,进一步指导科学研究及临床工作。  相似文献   
72.
目的探讨CT扫描在胸膜外孤立性纤维瘤(E-SFT)中的诊断价值。方法回顾性分析2015年4月至2018年4月于我院接受手术治疗的90例E-SFT患者术前CT检查影像资料和术后病理、免疫组织化学资料,评估CT检查在E-SFT诊断中的应用价值。结果 90例E-SFT患者均为单发肿瘤,免疫组织化学及病理学检查示良性80例,恶性10例;CT检查结果为良性72例,平扫表现为圆形或类圆形软组织密度影,密度不均匀,大部分边缘清晰,增强扫描表现为均匀强化;恶性18例,平扫示肿瘤体积较大,边界不清,密度不均,可见大片不规则低密度区,增强扫描瘤体强化不均匀,低密度区无明显强化;CT诊断的敏感度、准确度、特异性阳性率、阴性率分别为60%(6/10)、82%(74/90)、85%(68/80)、33%(6/18)、94%(68/72)。结论 E-SFT的CT检查影像图像具有一定的特征性,尤其是增强扫描有助于评估纤维瘤的良恶性,可将其作为术前诊断及术后复查评估的有效依据用于临床诊疗工作中。  相似文献   
73.
何敏  黄燕 《现代预防医学》2020,(23):4381-4384
目的 肺癌是全球发病率及死亡率最高的恶性肿瘤,患者5年生存率仍低于20%,提高早期诊断及筛查至关重要,本文对肺癌早期诊断方法进行文献综述。方法 检索PubMed、知网、万方、维普等数据库,选择与肺癌筛查相关的文献,进一步选择如CT、核磁共振、MiRNA、自身抗体等文献,提炼其相关结果结论。结果 肺癌早期诊断方法较多,每一种诊断方法均有其优缺点。结论 目前尚无任何一种技术被证实能独立完成早期肺癌的筛查,需要将目前早期诊断技术加以优化组合,以提高早期肺癌的诊断率。  相似文献   
74.
Background:Colon cancer is a common malignant tumor of the gastrointestinal tract. Therefore, a clear diagnosis is particularly important for the treatment of colon cancer. Ultrasound and spiral computed tomography (CT) can both be used in the diagnosis, but each has its own advantages and disadvantages, which could cause confusion in clinical choice. The purpose of this study was to systematically evaluate the practicability of spiral CT and ultrasound in the diagnosis of colon cancer.Methods:A systematic search was performed by retrieving on English databases (PubMed, Embase, Web of Science, the Cochrane Library) and Chinese databases (CNKI, Wanfang, Weipu [VIP], CBM). Besides, manually search for Google and Baidu academic of diagnostic experimental study of ultrasound and spiral CT in the diagnosis of Colon Cancer. The retrieval time limit was from the establishment of the database to October 2020. Two researchers independently extracted and evaluated the quality of the data in the included study. A meta-analysis was performed using Meta Disc1.4 and RevMan5.3 software.Results:Sensitivity, specificity, positive Likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were used to determine the diagnostic efficacy of ultrasonography and helical CT in colorectal cancer.Conclusions:This study will compare the practicability of CT and ultrasound in the diagnosis of colon cancer and provide reliable evidence-based basis for clinicians to choose the appropriate or best evidence-based basis.Ethics and dissemination:The private information from individuals will not be published. This systematic review also will not involve endangering participant rights. Ethical approval is not required. The results may be published in a peer-reviewed journal or disseminated in relevant conferences.OSF Registration number:DOI 10.17605/OSF.IO/WAJHQ  相似文献   
75.
We herein report a case of Klebsiella pneumoniae (K. pneumoniae) spondylitis and bacteremia in a 90-year-old man with diabetes mellitus who had undergone sigmoidectomy and had a fecalith. Two months prior to admission, he had received antimicrobial treatment for 2 weeks for K. pneumoniae bacteremia whose entry was unclear and he was readmitted to our hospital owing to fever and stomachache. K. pneumoniae was isolated from two sets of blood cultures, and computed tomography and magnetic resonance imaging revealed inflammation and destruction of the 8th and 9th thoracic vertebra. The diagnosis was spondylodiscitis secondary to K. pneumoniae bacteremia. Although the entry point for K. pneumoniae was unclear, we suggest that inflammation of the mucosa around the fecalith might have caused the Enterobacteriaceae bacteremia.  相似文献   
76.
77.
目的:探讨电子线对胰岛素生长因子-1家族蛋白表达的影响,为研究辐射对肝脏的早期损伤提供依据。方法:采用电子线照射小鼠,照射剂量为1、2、4 Gy,用Western blot法检测照射后12、48和72 h小鼠肝脏中胰岛素生长因子1受体(IGF-1R)、胰岛素生长因子结合蛋白1(IGFBP1)、胰岛素生长因子结合蛋白4(IGFBP4)和胰岛素生长因子1(IGF-1)蛋白表达水平的改变。结果:照射剂量为1 Gy时,与对照组相比,IGF-1蛋白在照射后48 h时表达增加,IGFBP1、IGFBP4和IGF1R蛋白的表达在照射后12、48和72 h均表达减少。照射剂量为2 Gy时,IGF-1和IGFBP4蛋白在照射后48 h时表达增加,其余时间点表达减少。IGFBP1蛋白在照射后12 h时表达增加,48和72 h时表达减少。IGF1R蛋白在照射后3个时间点均呈现为表达减少。照射剂量4 Gy时,肝脏中IGF-1、IGFBP1和IGFBP4蛋白均表达减少,IGF1R蛋白在照射后12 h时表达增加,48、72 h时均表达减少(均为P < 0.05)。结论:电子线照射后小鼠肝脏中胰岛素生长因子-1家族蛋白多以下调表达为主,与前期基因表达的结果相一致,有可能作为反映放射性工作人员早期肝脏损伤的生物标志物之一。  相似文献   
78.

Background

One daily dose of tacrolimus (QDT) improves adherence in kidney transplant (KT) recipients. A switch from twice-daily tacrolimus (BDT) to QDT showed similar efficacy and safety.

Methods

The aim of our study was to demonstrate the long-term efficacy and safety of switching from BDT to QDT in KT recipients. Preliminary results have already been published. Forty-one patients (34 men and 7 women), mean age at KT of 43.9 ± 12.7 years, underwent a 1:1 dose switch from BDT to QDT; the mean time from KT to switch was 36.6 ± 16.1 months. In our study population, 4 patients received a living donor KT and 2 received a second allograft.

Results

The mean follow-up was 86.8 ± 13 months from the switch and 126.2 ± 22.3 months from KT. Graft and patient survival rates were 90.2% and 95.1%, respectively. All patients maintained stable renal function during follow-up. During the first 3 months after the switch we observed a significant decrease in tacrolimus blood level (P = .0001). No significant differences were observed regarding tacrolimus dose before and after QDT introduction (P = not significant [NS]). Fourteen patients who stopped steroids under BDT treatment and 16 patients who stopped steroids after the switch are currently steroid-free.

Conclusion

Our study showed safety and efficacy in switching from BDT to QDT. After early (<1 year) dose adjustment, tacrolimus blood levels remained stable throughout follow-up. Moreover, QDT represented a valid alternative for patients showing steroid side effects.  相似文献   
79.
Additive manufacturing is a rapidly emerging technology which is being successfully implemented in the various field of medicine as well as in orthopaedics, where it has applications in reducing cartilage defects and treatments of bones. The technology helps through systematic collection of information about the shape of the "defects" and precise fabrication of complex 3D constructs such as cartilage, heart valve, trachea, myocardial bone tissue and blood vessels. In this paper, a large number of the relevant research papers on the additive manufacturing and its application in medical specifically orthopaedics are identified through Scopus had been studied using Bibliometric analysis and application analysis is undertaken. The bibliometric analysis shows that there is an increasing trend in the research reports on additive manufacturing applications in the field of orthopaedics. Discussions are on using technological advancement like scanning techniques and various challenges of the orthopaedic being met by additive manufacturing technology. For patient-specific orthopaedic applications, these techniques incorporate clinical practice and use for effective planning. 3D printed models printed by this technology are accepted for orthopaedic surgery such as revision of lumbar discectomy, pelvic surgery and large scapular osteochondroma. The applications of additive manufacturing in orthopaedics will experience a rapid translation in future. An orthopaedic surgeon can convert need/idea into a reality by using computer-aided design (CAD) software, analysis software to facilitate the manufacturing. Thus, AM provides a comprehensive opportunity to manufacture orthopaedic implantable medical devices.  相似文献   
80.
目的探讨帕金森病(PD)的CT表现及微电极导向脑内核团毁损术后CT影像特点。资料与方法(1)对240例PD患者术前CT影像进行回顾性分析。(2)30例PD患者在术后3~12个月(平均6·5个月)CT扫描,观测脑内核团毁损灶33个(其中3例患者为双侧手术):右苍白球腹后内侧核(Gpi)毁损灶14个、左Gpi核毁损灶6个,右丘脑腹外侧核(Vim)毁损灶2个、左Vim核毁损灶11个,对毁损灶最大层面积、术侧CT值(任意值)、健侧对应点CT值(标准值)测量,并算出毁损灶与健侧CT值的差值。结果(1)PD的CT表现主要为中央型弥漫性脑萎缩,以脑室系统扩大为主,轻度脑萎缩46.67%(112/240),中度脑萎缩40%(96/240),重度脑萎缩3.33%(8/240),正常10%(24/240)。(2)33个毁损靶灶之圆形占27·27%(9/33);类圆形占60·61%(20/33);片状不规则形占12·12%(4/33)。毁损灶的面积Gpi核平均(28·01±2.15)mm2,Vim核平均为(14.03±1.24)mm2,两者对比有显著性差异(P<0.01);毁损灶Gpi核CT值较健侧平均下降(11.80±0.87)HU,Vim核CT值较健侧平均下降(10.80±1.28)HU,两者亦有差异性(P<0·05)。结论PD患者术前CT扫描对掌握手术适应证较重要,重度脑萎缩患者提示不宜做外科手术治疗。术后CT扫描观察毁损灶之形态、面积、密度变化等影像学改变,有利于对手术疗效、并发症等评估提供一定证据。  相似文献   
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