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991.
上转换发光纳米材料(UCNPs)具有荧光寿命长、潜在生物毒性低、穿透深度大、对生物组织损伤小且几乎没有背景光等显著优点,近年来,在光动力治疗(PDT)、生物成像及生物检测等领域已经得到广泛应用.但在应用的过程中存在一些缺陷,如在PDT中UCNPs与光敏剂之间能量转移效率较低、正常组织过热;在生物成像中,荧光强度较弱、光敏剂和激活剂有能量回流、成像模式单一等问题.科研人员针对上述问题研究出了很多解决的方法,如缩短UCNPs与目标物之间的距离、改变照射激光的强度、改变UCNPs的结构、将UCNPs作为新型多功能平台整合成像与治疗于一体等,使部分问题得到了很好的解决.本文重点综述了UCNPs应用在PDT和生物成像中所出现的问题及解决方法,并对UCNPs在生物医学领域的应用发展趋势进行展望. 相似文献
992.
Furazolidone‐containing triple and quadruple eradication therapy for initial treatment for Helicobacter pylori infection: A multicenter randomized controlled trial in China 下载免费PDF全文
Yong Xie Zhenyu Zhang Junbo Hong Wenzhong Liu Hong Lu Yiqi Du Weihong Wang Jianming Xu Xuehong Wang Lijuan Huo Guiying Zhang Chunhui Lan Xiaoyan Li Yanqing Li Hong Wang Guoxin Zhang Yin Zhu Xu Shu Ye Chen Jiangbin Wang Nonghua Lu the Chinese Society of Gastroenterology Chinese Study Group on Helicobacter pylori 《Helicobacter》2018,23(5)
Background
The efficacy of Helicobacter pylori (H. pylori) eradication has steadily declined, primarily because of antibiotic resistance. This study aimed to evaluate the efficacy and safety of furazolidone eradication therapies as initial treatments for H. pylori infection.Methods
A national, multicenter, open‐label, randomized controlled trial was performed at 16 sites across 13 provinces in China to evaluate the efficacy and safety of furazolidone‐containing therapies for H. pylori infection. Treatment naïve patients were randomly assigned to: esomeprazole 20 mg, bismuth 220 mg, amoxicillin 1000 mg, and furazolidone 100 mg twice daily for 10 and 7 days (FAB 10 and FAB 7; the same therapy without bismuth (FA 10 and FA 7). The primary and secondary outcomes were the eradication rate and regimen safety, respectively. Treatment success was assessed by the 13C urea breath test at least 4 weeks after treatment completion.Results
Overall, according to intention‐to‐treat (ITT) analysis, the eradication rates for FAB 10 and FAB 7 were 86.6% (95% confidence interval [CI], 79.9%‐93.2%) and 83.6% (95% CI, 76.3%‐90.9%) and for FA 10 and FA 7 were 82.4% (95% CI, 74.9%‐89.8%) and 77.6% (95% CI, 69.4%‐85.8%), respectively. According to per‐protocol analysis, the overall eradication rates for FAB 10 and FAB 7 were 94.7% (95% CI, 90.3%‐99.1%) and 90.8% (95% CI, 85.1%‐96.5%) and for FA 10 and FA 7 were 90.6% (95% CI, 84.9%‐96.3%) and 85.1% (95% CI, 78.2%‐92.1%), respectively. The overall prevalence of side effects was 8.1%.Conclusions
Furazolidone‐containing therapies, particularly the tested 10‐day quadruple therapy, exhibited satisfactory efficacy and safety. This 10‐day quadruple therapy represents a promising initial treatment strategy for Chinese patients. 相似文献993.
Comparative study of Helicobacter pylori eradication rates of concomitant therapy vs modified quadruple therapy comprising proton‐pump inhibitor,bismuth, amoxicillin,and metronidazole in Korea 下载免费PDF全文
994.
Vonoprazan‐ vs proton‐pump inhibitor‐based first‐line 7‐day triple therapy for clarithromycin‐susceptible Helicobacter pylori: A multicenter,prospective, randomized trial 下载免费PDF全文
995.
Tomohei Nakao Hiroko Fukushima Takashi Fukushima Ryoko Suzuki Sho Hosaka Yuni Yamaki Chie Kobayashi Atsushi Iwabuchi Kazuo Imagawa Aiko Sakai Toko Shinkai Kouji Masumoto Shingo Sakashita Tomohiko Masumoto Masashi Mizumoto Ryo Sumazaki Hideyuki Sakurai 《Reports of Practical Oncology and Radiotherapy》2018,23(5):442-450
Aim
To assess the feasibility of transferring to the University of Tsukuba Hospital for proton beam therapy (PBT) during intensive chemotherapy in children with Ewing sarcoma family of tumors (ESFT) who had been diagnosed and started their first-line treatment at prefectural or regional centers for pediatric oncology.Background
The treatment of ESFT relies on a multidisciplinary approach using intensive neoadjuvant and adjuvant chemotherapies with surgery and radiotherapy. Multi-agent chemotherapy comprising vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide (VDC-IE) is widely used for ESFT, and the interval between each course is very important for maintaining the intensity and effect of chemotherapy.Materials and methods
Clinical information of patients who received PBT and VDC-IE between April 2009 and May 2016 was collected retrospectively. The intervals between each course of VDC-IE and adverse events were assessed.Results
Fifteen patients were evaluated. No delays in the intervals of chemotherapy due to transfer were observed. There were no adverse events caused during/just after transfer and no increases in adverse events. The estimated 4-year overall and event-free survival rates were 94.6% and 84.8%, respectively.Discussion
Although the results of efficacy are preliminary, survival rates were comparable with past studies. More experience and follow-up are required to further assess the efficacy of PBT for patients with ESFT.Conclusion
Multidisciplinary therapy for children with ESFT involving transfer to our hospital for PBT during VDC-IE was feasible without treatment delay or an increase in adverse events. 相似文献996.
Hidekazu Tanaka Takahiro Yamaguchi Kae Hachiya Kazuhiro Miwa Jun Shinoda Masahide Hayashi Shinichi Ogawa Hironori Nishibori Satoshi Goshima Masayuki Matsuo 《Reports of Practical Oncology and Radiotherapy》2018,23(3):215-219
Aim
To define the optimal margin on MRI scans in the re-radiation planning of recurrent glioblastoma using methionine positron emission tomography (MET-PET).Background
It would be very useful if the optimal margin on MRI to cover the uptake area on MET-PET is known.Materials and Methods
CT, MRI, and MET-PET were performed separately over the course of 2 weeks. Among the MRI scans, we used the contrast-enhanced T1-weighted images (Gd-MRI) and T2-weighted images (T2-MRI). The Gd-MRI-based clinical target volume (CTV) (CTV-Gd) and the T2-MRI-based CTV (CTV-T2) were defined as the contrast-enhanced area on Gd-MRI and the high intensity area on T2-MRI, respectively. We defined CTV x mm (x = 5, 10, 15, 20) as x mm outside the CTV. MET-PET-based CTV (CTV-MPET) was defined as the area of accumulation of MET-PET. We calculated the sensitivity and specificity of CTV-Gd and CTV-T2 following comparison with CTV-MPET, which served as the gold standard in this study.Results
The sensitivity of CTV-T2 5 mm (98%) was significantly higher than CTV-T2 (87%), and there was no significant difference in the sensitivity between CTV-T2 5 mm and CTV T2 10, 15, or 20 mm. The sensitivity of CTV-Gd 20 mm (97%) was lower than that of CTV-T2 5 mm (98%).Conclusions
A margin of at least 5 mm around the high intensity area on T2-MRI is necessary in the target volume delineation of recurrent glioblastoma for the coverage of MET-PET findings in re-radiation therapy planning. 相似文献997.
Annamaria Didona Valentina Lancellotta Claudio Zucchetti Bianca Moira Panizza Alessandro Frattegiani Martina Iacco Anna Concetta Di Pilato Simonetta Saldi Cynthia Aristei 《Reports of Practical Oncology and Radiotherapy》2018,23(3):175-182
Background
Intensity-modulated radiotherapy (IMRT) improves dose distribution in head and neck (HN) radiation therapy. Volumetric-modulated arc therapy (VMAT), a new form of IMRT, delivers radiation in single or multiple arcs, varying dose rates (VDR-VMAT) and gantry speeds, has gained considerable attention. Constant dose rate VMAT (CDR-VMAT) associated with a fixed gantry speed does not require a dedicated linear accelerator like VDR-VMAT. The present study explored the feasibility, efficiency and delivery accuracy of CDR-VMAT, by comparing it with IMRT and VDR-VMAT in treatment planning for HN cancer.Methods and materials
Step and shoot IMRT (SS-IMRT), CDR-VMAT and VDR-VMAT plans were created for 15 HN cancer patients and were generated by Pinnacle3 TPS (v 9.8) using 6 MV photon energy. Three PTVs were defined to receive respectively prescribed doses of 66 Gy, 60 Gy and 54 Gy, in 30 fractions. Organs at risk (OARs) included the mandible, spinal cord, brain stem, parotids, salivary glands, esophagus, larynx and thyroid. SS-IMRT plans were based on 7 co-planar beams at fixed gantry angles. CDR-VMAT and VDR-VMAT plans, generated by the SmartArc module, used a 2-arc technique: one clockwise from 182° to 178° and the other one anti-clockwise from 178° to 182°. Comparison parameters included dose distribution to PTVs (Dmean, D2%, D50%, D95%, D98% and Homogeneity Index), maximum or mean doses to OARs, specific dose-volume data, the monitor units and treatment delivery times.Results
Compared with SS-IMRT, CDR-VMAT significantly reduced the maximum doses to PTV1 and PTV2 and significantly improved all PTV3 parameters, except D98% and D95%. It significantly spared parotid and submandibular glands and was associated with a lower Dmean to the larynx. Compared with VDR-VMAT, CDR-VMAT was linked to a significantly better Dmean, to the PTV3 but results were worse for the parotids, left submandibular gland, esophagus and mandible. Furthermore, the Dmean to the larynx was also worse. Compared with SS-IMRT and VDR-VMAT, CDR-VMAT was associated with higher average monitor unit values and significantly shorter average delivery times.Conclusions
CDR-VMAT appeared to be a valid option in Radiation Therapy Centers that lack a dedicated linear accelerator for volumetric arc therapy with variable dose-rates and gantry velocities, and are unwilling or unable to sanction major expenditure at present but want to adopt volumetric techniques. 相似文献998.
Marisa R. Moroney Dina Flink Jeanelle Sheeder Erin A. Blake Aakriti R. Carrubba Christine M. Fisher Saketh R. Guntupalli 《Reports of Practical Oncology and Radiotherapy》2018,23(5):331-336
Aim
To evaluate the associations of external beam radiation therapy (EBRT) and intracavitary brachytherapy (IB) with decreased sexual function.Background
There’s inconsistent evidence on whether radiation for gynecologic cancers has an impact on sexual health. IB, an underutilized treatment modality, is thought to have less adverse effects than EBRT.Materials and methods
A cross-sectional study examining decreased sexual function following radiation for gynecologic cancers. A decrease in sexual function was measured as a change in the Female Sexual Function Index (FSFI) from before to after treatment, with a significant decrease determined by Reliable Change Index Statistic (RCIS). Chi-square and t-tests were employed.Results
171 women completed the survey; 35% (n?=?60) received radiation, of whom 29 received EBRT and IB (48%), 15 EBRT alone (25%), 16 IB alone (27%). Women who received radiation had similar rates of decreased sexual function as women who did not (47% vs. 38%, P?=?0.262). EBRT and IB had similar rates of decreased sexual function compared to women with no radiation (50% vs. 38% P?=?0.166 and 47% vs. 38% P?=?0.309). Women experiencing decreased sexual function were more likely to be under 50 years old (OR 5.4, 95%CI 1.6–18.1), have received chemotherapy (OR 5.7, 95%CI 1.4–22.9), and have cervical cancer (OR 7.8, 95%CI 2.1–28.8).Conclusions
Treatment with EBRT or IB does not appear to impair sexual function in women with gynecologic cancer. Age less than 50, concurrent chemotherapy, and cervical cancer may place women with gynecologic cancer at higher risk for decreased sexual function following radiation. 相似文献999.
Tomasz Kolenda Weronika Przybyła Marta Kapałczyńska Anna Teresiak Maria Zajączkowska Renata Bliźniak Katarzyna M. Lamperska 《Reports of Practical Oncology and Radiotherapy》2018,23(3):143-153
Head and neck squamous cell carcinomas (HNSCC) are in a group of cancers that are the most resistant to treatment. The survival rate of HNSCC patients has been still very low since last 20 years. The existence of relationship between oncogenic and surrounding cells is probably the reason for a poor response to treatment. Fibroblasts are an important element of tumor stroma which increases tumor cells ability to proliferate. Another highly resistance, tumorigenic and metastatic cell population in tumor microenvironment are cancer initiating cells (CICs). The population of cancer initiating cells can be found regardless of differentiation status of cancer and they seem to be crucial for HNSCC development.In this review, we describe the current state of knowledge about HNSCC biological and physiological tumor microenvironment. 相似文献
1000.
Wui Ann Woon Paul B. Ravindran Piyasiri Ekanayake Siti Amirah Yivonne Y.F. Lim Christopher H.S. Vun Jamsari Khalid 《Reports of Practical Oncology and Radiotherapy》2018,23(5):346-359