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排序方式: 共有2141条查询结果,搜索用时 312 毫秒
41.
Constantino S. Peña Volkan Tuncay James F. Benenati Alex Powell Ripal T. Gandhi Brian J. Schiro Martine van Alfen Barry T. Katzen 《Journal of vascular and interventional radiology : JVIR》2021,32(2):220-225.e2
PurposeTo evaluate the impact of a versatile flexible ceiling-mounted C-arm on active table and gantry repositioning during interventions and its effect on operator discomfort, system usability, and patient safety compared with a traditional ceiling-mounted system.Materials and MethodsThere were 100 IR procedures studied: 50 in a traditional IR system (standard group) and 50 with a novel multiaxis ceiling-mounted system (test group). FlexArm was capable of multiple gantry rotation points allowing increased access to the patient in addition to 236 cm of lateral x-ray detector travel. For each procedure, both the table and the gantry repositioning were measured. Patient safety, patient/equipment repositioning effort, and physical discomfort were evaluated through an operator survey.ResultsTable repositioning was reduced from 42 to 16 instances per procedure (P < .001) in the test group compared with the standard group. The operators perceived less table and gantry repositioning effort (P < .0001) and decreased risks of equipment collisions, displacement of vascular access, and dislodgment of tubes/lines with the test group (P < .0001). Operator discomfort was reduced for all body areas in the test group over the standard group (P < .0001).ConclusionsThe FlexArm system geometry enhances operator ergonomics, as there was a decrease need to move the table, leading to a perceived decrease in patient risk and decrease operator physical discomfort when compared to a traditional imaging system. 相似文献
42.
Elif Ergun Betül Şimşek Pınar Nercis Koşar Behice Kaniye Yılmaz Ahmet Tuncay Turgut 《Surgical and radiologic anatomy : SRA》2013,35(6):503-509
Purpose
To review the 64-slice CTA (computed tomography angiography) appearance of anatomical variations in branching pattern of the arcus aorta, and to determine their prevalence in 1001 cases.Materials and methods
1001 cases that underwent carotid CTA (performed by a 64-slice scanner) were included in the study.Results
Seven types of aortic arch were found. In 853 cases (853/1001, 85.2 %) classical branching pattern of arcus aorta (three branches; TB, LCC, LS) was observed. Variations were present in 147 cases (147/1001, 14.7 %). One case (1/1001, 0.1 %) had right aortic arch. The most frequent variation was origination of LCC from TB (arch with 2 branches, TB with LCC and LS) which was observed in 78 cases (78/1001, 7.8 %). Origination of LV directly from the aortic arch (four branches; TB, LCC, LV, LS or TB, LCC, LS, LV) was observed in 51 cases (51/1001, 5.1 %). In two cases (2/1001, 0.2 %) truncus bicaroticus (3 branches; RS, common trunk for carotids, LS) was present. In seven cases (7/1001, 0.7 %) aortic arch had four branches in the order of RCC, RS, LCC and LS. In one case (1/1001, 0.1 %) left truncus brachiocephalicus (three branches; RS, RCC, LTB) was present. Seven cases (7/1001, 0.7 %) had aberrant RS (RCC, LCC, LS, RS).Conclusion
Variations in branching pattern of arcus aorta are not rare and being aware of them before surgical and interventional procedures of this region is important. CTA can depict the anatomical features of the aortic arch and is valuable as a road map. 相似文献43.
Falk Wehrhan Manuel Weber Christoph Baran Abbas Agaimy Maike Büttner-Herold Marco Kesting Jutta Ries 《Journal of cranio-maxillo-facial surgery》2021,49(2):118-125
ObjectivesThis study analyzed the expression of the PD1 receptor in tumor tissue and peripheral blood of oral squamous cell carcinoma (OSCC) patients, and correlated it with the PD1 ligands PD-L1 and PD-L2. The currently low response rates of checkpoint inhibitor treatment in OSCC could be increased by a better understanding of immune checkpoint biology. Despite evidence in the literature for upregulation of PD1 checkpoint ligands in OSCC tissue, there has been no correlation analysis of the PD1 receptor with its ligands in tissue specimens and peripheral blood of OSCC patients.Materials and methodsAn RT-qPCR analysis of PD1 mRNA expression was performed in oral cancer specimens, healthy mucosa, and corresponding blood samples. A cut-off point (COP) was determined and a chi-square (χ2) test was carried out. PD1 expression was correlated with previously reported PD-L1 and PD-L2 expression values using the Spearman test.ResultsTissue and blood specimens of 48 OSCC patients and 26 healthy individuals were analyzed. PD1 expression in OSCC specimens was significantly increased (p = 0.006) compared with healthy oral mucosa. PD1 overexpression in tissue samples showed a significant association with the presence of malignancy (p = 0.006). PD1 expression in tissue samples showed a significant positive correlation (p < 0.001) with the ligands PD-L1 and PD-L2. In contrast, there was no correlation between PD1 and its ligands in blood samples. However, there was a significant positive correlation (p < 0.001) between the ligands PD-L1 and PD-L2, both in tissue and blood samples.ConclusionsIncreased PD1 expression might be a manifestation of T-cell exhaustion in OSCC specimens, leading to immune tolerance. PD-L1/PD-L2-PD1 interaction may be a major mediator of local immunosuppression in OSCC, requiring advanced multimodal treatment protocols. 相似文献
44.
Alexey Maximenko Joanna Depciuch Natalia opuszyska Malgorzata Stec aneta
wiatkowska-Warkocka Vadim Bayev Piotr M. Zieliski Jaroslaw Baran Julia Fedotova Wadysaw P. Wglarz Magdalena Parlinska-Wojtan 《RSC advances》2020,10(44):26508
Novel functionalized (biofunctionalization followed by cisplatin immobilization) Fe3O4@SiO2@Au nanoparticles (NPs) were designed. The encapsulation of Fe3O4 cores inside continuous SiO2 shells preserves their initial structure and strong magnetic properties, while the shell surface can be decorated by small Au NPs, and then cisplatin (cPt) can be successfully immobilized on their surface. The fabricated NPs exhibit very strong T2 contrasting properties for magnetic resonance imaging (MRI). The functionalized Fe3O4@SiO2@Au NPs are tested for a potential application in photothermal cancer therapy, which is simulated by irradiation of two colon cancer cell lines (SW480 and SW620) with a laser (λ = 808 nm, W = 100 mW cm−2). It is found that the functionalized NPs possess low toxicity towards cancer cells (∼10–15%), which however could be drastically increased by laser irradiation, leading to a mortality of the cells of ∼43–50%. This increase of the cytotoxic properties of the Fe3O4@SiO2@Au NPs, due to the synergic effect between the presence of cPt plus Au NPs and laser irradiation, makes these NPs perspective agents for potential (MRI)-guided stimulated chemo-photothermal treatment of cancer.Novel functionalized nanoparticles, with toxicity controlled by laser irradiation, are perspective agents for potential (MRI)-guided stimulated chemo-photothermal treatment of cancer. 相似文献
45.
Steinkamp Pieter Jan Voskuil Floris Jan van der Vegt Bert Doff Jan Johannes Schepman Kees-Pieter de Visscher Sebastiaan Antonius Hendrik Johannes Kelder Wendy Jayalakshmi Yalia Gao Jinming Sumer Baran Devrim van Dam Gooitzen Michell Witjes Max Johannes Hendrikus 《Molecular imaging and biology》2021,23(6):809-817
Molecular Imaging and Biology - Intra-operative management of the surgical margin in patients diagnosed with head and neck squamous cell carcinoma (HNSCC) remains challenging as surgeons still have... 相似文献
46.
ABSTRACTIntroduction: Acne vulgaris is a widespread skin disease. Topical therapy is a standard treatment for mild to moderate acne. Given the complex pathophysiology of acne, various agents with complementary action are nowadays frequently combined to increase the efficacy of therapy.Area covered: This review focus on safety profile of topical agents used for the treatment of acne vulgaris, including topical retinoids, benzyl peroxide, azelaic acid, topical antibiotic, and combined agents. Data from clinical trials but also metanalyses, systematic reviews, and other secondary analyses are presented.Expert opinion: In general, topical agents used for acne vulgaris have a favorable safety profile. The most commonly reported AEs were associated with local skin irritation, usually mild to moderate in intensity, intermittent, and rarely led to the cessation of therapy. Irritative potential seems to be highest for BPO and topical retinoids. Due to the possibility of development of Cutibacterium acnes resistance, topical antibiotics should not be used in monotherapy but as a part of combination therapy. In female adolescent and adults of childbearing potential, topical retinoids should be used with caution, because they are contraindicated in pregnant females (FDA Pregnancy category) C (adapalene, tretinoin) and X (tazarotene). 相似文献
47.
Ecotoxicological characteristics and ecological risk assessment of trace elements in the bottom sediments of the Rożnów reservoir (Poland) 总被引:1,自引:0,他引:1
Szara Magdalena Baran Agnieszka Klimkowicz-Pawlas Agnieszka Tarnawski Marek 《Ecotoxicology (London, England)》2020,29(1):45-57
Ecotoxicology - The bottom sediments in catchment areas behind dams play a significant role in water ecosystems. On the other hand, the structure of sediments makes them a natural geosorbent, in... 相似文献
48.
Kurt M Ozkan L Kurt E Cetintas SK Aygun S Ercan I Yilmazlar T Memik F 《Hepato-gastroenterology》2008,55(85):1158-1163
BACKGROUND/AIMS: 5-Fluorouracil-based chemoradiotherapy is the most widely used treatment modality in the adjuvant treatment of rectal cancer. Capecitabine represents a valuable alternative to 5-Fluorouracil in this situation. METHODOLOGY: Patients with stage II and stage III rectal adenocarcinoma, who were included in this analysis, received adjuvant chemoradiotherapy consisting of external-beam radiotherapy (50.4-54Gy) either with 5-Fluorouracil at a median dose of 300 mg/m2/day by protracted venous infusion for 5 days a week, or capecitabine at a median dose of 1650 mg/m2/day for 5 days a week after surgery. The data concerning the toxicity and the efficacy of the treatments were compared in patients treated with 5-Fluorouracil- and capecitabine-based chemoradiotherapy. RESULTS: Forty-three patients received 5-Fluorouracil, and 24 patients received capecitabine during adjuvant radiotherapy. Although there were no differences between the groups in terms of toxicity rates, distant metastasis-free survival, disease-free survival, and overall survival rates; a trend for improved loco-regional recurrence-free survival rate was observed in the capecitabine arm (p = 0.063). CONCLUSIONS: Capecitabine is at least as effective as 5-Fluorouracil in the postoperative treatment of rectal adenocarcinoma. Considering the trend for improved loco-regional recurrence-free survival rate in the capecitabine arm, it seems that the drug exerts better synergy with radiotherapy in this situation. 相似文献
49.
Necessity of Keratinized Tissues for Dental Implants: A Clinical,Immunological, and Radiographic Study
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50.
Muhsin Kaya Şengül Baran Cemil Güya Mehmet Ali Kaplan 《Indian journal of gastroenterology》2016,35(3):201-206