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BackgroundApproximately 15% of patients with colorectal cancer present with locally advanced tumors (T4 stage). Laparoscopic surgery for stage T4 disease has not yet been established.The near-infrared ray catheter fluorescent ureteral catheter (NIRFUC) is a new device that uses near-infrared fluorescence resin.We examined the utility of fluorescence ureteral navigation (FUN) with the NIRFUC during laparoscopic surgery for stage T4 colorectal cancer.Materials and methodsPatients with stage T4 colorectal cancer (n = 143, from January 2017 to March 2021) were divided into a T4FUN + group, in which the NIRFUC was used (n = 21), and a T4FUN- group, in which the NIRFUC was not used (n = 122). Short-term outcomes were compared between the groups.Next, the laparoscopic surgery rate and incidence of ureteral injury from January 2017 to March 2021 were compared between the T4FUN- group and the non-stage T4FUN- group (n = 434, from January 2017 to March 2021), in which fluorescence ureter navigation was not used.ResultsRectal cancer, stage T4b disease, and invasion into the urinary tract were observed more often in the T4FUN + group than in the T4FUN- group.In the comparisons of the T4FUN + versus T4FUN- groups, the operative time was 398 (161–1090) vs. 256 (93–839) minutes, the blood loss was 10 (1–710) vs. 25 (0–1360) ml, and the ratio of laparoscopic surgery to open surgery was 21:0 vs. 79:43. Postoperative complications (Clavien-Dindo grade ≥ III) were present in 2 (10%; 0 ureteral injury) patients in the T4FUN + group and 13 (11%; 2 ureteral injury) patients in the T4FUN- group.In the T4FUN + group, the operative time was longer (p < 0.0001), but the laparoscopic ratio was higher (p = 0.0002), and the blood loss volume and incidence of ureteral injury tended to be lower.In the comparisons of the T4FUN- versus non-stage T4FUN- groups, the ratio of laparoscopic surgery to open surgery was 79:43 vs. 384:50, the incidence of open conversion was 8 (6.6%) vs. 15 (3.5%), and the incidence of ureteral injury was 2 (1.6%) vs. 0 (0%). In the T4FUN- group, the open surgery rate (<0.0001), open conversion rate (p = 0.0205) and incidence of ureteral injury (p = 0.0478) were high, with a significant difference observed between the groups.ConclusionPatients with stage T4 disease have an increased risk of ureteral injury and are more likely to be converted to open surgery.FUN can help to safely increase the laparoscopic surgery rate while safely visualizing the ureter. FUN is recommended for laparoscopic surgery in patients with stage T4 colorectal cancer.Clinical trial registrationExamination of fluorescence navigation for laparoscopic colorectal cancer surgery; Research Ethics Committee of the Kawaguchi Municipal Medical Center (Saitama, Japan) approval number: 2020-3. https://kawaguchi-mmc.org/wp-content/uploads/clinical research-r02.pdf;  相似文献   
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Amphiphilic polymer conetworks (APCNs), which combine two different polymer nanophases, have a broad range of applications that involve their unique potential to separately swell one of these nanophases in a selective solvent. Little is known about the structural changes of such APCNs upon swelling in dependence on the topology. Here, conetworks composed of poly(2‐ethylhexyl acrylate) crosslinked by poly(2‐methyl‐2‐oxazoline) (PMOx) are investigated with small‐angle X‐ray scattering in dry and swollen state using the orthogonal solvents water and toluene. The data clearly show that the structural changes induced by swelling are strongly dependent on the topology of the APCNs. While water leads to fusion of PMOx phases resulting in larger structures than found in the dry APCN, toluene is only swelling the hydrophobic phases without structural changes.  相似文献   
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In the quest for new active molecules against Mycobacterium tuberculosis, a series of dihydroquinoline derivatives possessing triazolo substituents were efficiently synthesized using click chemistry. The structure of 6l was evidenced by X‐ray crystallographic study. The newly synthesized compounds were evaluated for their in vitro antitubercular activity against Mycobacterium tuberculosis H37Rv (ATCC27294). The compounds 6a , 6g, and 6j (MIC: 3.13 μg/ml) showed promising activity when compared to the first‐line drug such as ethambutol. In addition, the structure and antitubercular activity relationship were further supported by in silico molecular docking studies of the active compounds against 3IVX.PDB (crystal structure of pantothenate synthetase in complex with 2‐(2‐(benzofuran‐2‐ylsulfonylcarbamoyl)‐5‐methoxy‐1H‐indol‐1‐yl)acetic acid).  相似文献   
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Cisplatin resistance is caused, in part, by the efficient removal of the helix‐distorting cisplatin 1,2‐intrastrand cross‐links by nucleotide excision repair (NER) machinery. To make a platinum‐DNA adduct that causes less helical distortion than the cisplatin 1,2‐intrastrand adduct, we designed and synthesized a monofunctional platinum‐carbazole conjugate (carbazoplatin). The 2.5 Å crystal structure of carbazoplatin‐DNA adduct revealed both the monoplatination of the N7 of a guanine (G) base and the intercalation into two G:C base pairs, while causing a minor distortion of the DNA helix. A 50‐mer dsDNA containing a single carbazoplatin lesion was poorly processed by UvrABC endonuclease, the prokaryotic NER machinery that detects helical distortion and performs dual incision around the lesion. Our cell viability assay indicated that the cytotoxic pathways of carbazoplatin might be different from those of cisplatin; carbazoplatin was 5–8 times more cytotoxic than cisplatin against PANC‐1 and MDA‐MB‐231 cancer cell lines.  相似文献   
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阻塞性睡眠呼吸暂停综合征患者舌后区上呼吸道CT测量   总被引:5,自引:1,他引:5  
目的 对阻塞性睡眠呼吸暂停综合征(obstructive sleep apnea syndrome,OSAS)患者和健康人的舌体及舌后区上呼吸道的CT测量资料进行对比研究。方法 OSAS患者共59例,年龄与性别相近的健康成年人57名,采用螺旋CT对上呼吸道进行连续扫描,观察2组舌后区上呼吸道形态学的差异,测量并比较舌后区气道和舌体各测量参数的差别。结果 患者多表现为气道前后径大于左右径、颏舌肌分离、舌根与软腭接触和舌正中切迹。患者组舌后区上呼吸道的横截面积、左右径明显小于对照组;咽侧壁软组织厚度、舌体宽度、颏舌肌宽度、舌骨舌肌宽度和舌体横截面积均明显大于对照组;呼吸道前后径、咽后壁软组织厚度和舌体长度与对照组相比无明显变化。结论 OSAS患者舌后区上呼吸道较健康对照组狭窄,除咽侧壁软组织增厚外,颏舌肌、舌骨舌肌和舌体宽度的增加也是造成舌后区上呼吸道狭窄的主要原因。  相似文献   
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