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1.
PurposeTo compare the characteristics of polidocanol (POL) and ethanolamine oleate (EO) sclerosing foams produced by a Shirasu porous glass membrane (SPGM) device with those made using a 3-way stopcock (3WSC).Materials and MethodsFoam half-life times were measured in an ex-vivo benchtop study. Computed tomography (CT) images of each foam were obtained over the time course, and a CT texture analysis was conducted. The bubble size in each foam was measured by an optical microscope.ResultsMedian foam half-life times were longer in the SPGM group than in the 3WSC group (POL: 198 vs 166 s, P = .02; EO: 640 vs 391 s, P < .01). In the CT texture analysis, median standard deviation (SD) and entropy (randomness) were lower, and median energy (uniformity) and gray-level cooccurrence matrix (GLCM) homogeneity were higher in the SPGM group than in the 3WSC group (POL SD: at 30 s and 50–300 s; POL entropy: at 0–60 s; EO SD: at 0–600 s; EO entropy: at 0–460 s; POL energy: at 0–40 s; POL GLCM homogeneity: at 0–250 s; EO energy: at 0–360 s; EO GLCM homogeneity: at 0–480 s; all P < .05). Median bubble diameters in the SPGM group and in the 3WSC group were 69 and 83 μm (P < .01), respectively, in the POL foam; and 36 and 36 μm (P = .45), respectively, in the EO foam.ConclusionsPOL and EO foams had greater uniformity and longer foam half-life time when prepared with an SPGM device than with a 3WSC.  相似文献   
2.
目的分析三维重建指导胸腔镜肺段切除术诊治磨玻璃结节(GGN)的效果。 方法回顾性分析2020年10月至2021年6月于北京大学国际医院接受三维重建指导胸腔镜肺段切除术9例GGN患者临床资料。 结果9例患者均顺利完成三维重建指导胸腔镜肺段切除术,其中,右肺上叶2例,右肺下叶1例,左肺上叶5例,左肺下叶1例,无中转开胸,R0切除率为100%。手术时间(377.89±115.96)min,术中出血为(150.00±96.82)ml。术后最高视觉模拟评分法(VAS)评分为(3.67±0.71)分,术后引流时间(6.33±2.39)d,术后引流总量(1 278.89±511.23)ml,术后住院时间(8.78±2.68)d。术后引流时间>7 d者1例(11.11%),拔管延迟原因为肺漏气。9例患者均出现术后并发症,其中,1级4例,2级5例,无3~5级严重并发症或围术期死亡。清扫淋巴结3~6组[(4.89±1.05)组],清扫淋巴结11~20个[(14.00±2.73)个]。 结论三维重建指导胸腔镜肺段切除术诊治GGN安全有效。  相似文献   
3.
BackgroundGrossman described the ideal properties of root canal sealers. The International Organization for Standardization and American National Standards Institute and American Dental Association have codified some of his requirements in ISO 6876 and ANSI/ADA 57, respectively. In this narrative review, the authors combined the ideal Grossman properties and requirements of these standards, emphasizing the newer tricalcium silicate cement sealers. This chemical matrix for such sealers was developed on the basis of the success of bioactive mineral trioxide aggregate–type (tricalcium silicate cement) materials for enhanced sealing and bioactivity.MethodsThe authors searched the internet and databases using Medical Subject Heading terms and then conducted a narrative review of those articles involving the tricalcium silicate cement endodontic sealers.ResultsNinety-four articles were identified that discussed tricalcium silicate cement sealers. Tricalcium silicate cement sealers are partially antimicrobial and have bioactivity, which may presage improved biological sealing of the root canal system. Most other properties of tricalcium silicate cement sealers are comparable with traditional root canal sealers.ConclusionsWithin the limitations of this review, tricalcium silicate cement endodontic sealers met many of the criteria for ideal properties, such as placement, antimicrobial properties, and bioactivity, but limitations were noted in solubility, dimensional stability (shrinkage and expansion), and retrievability.Practical ImplicationsTricalcium silicate–based cements have been commercialized as bioactive, bioceramic endodontic sealers. Warm, cold, and single-cone obturation techniques are usable, depending on the commercial product. Some sealers can cause discoloration and are not easily retrievable, particularly when used to completely obturate a canal.  相似文献   
4.
BackgroundRepairing crowns with defective margins is minimally invasive and cost-effective compared with replacement. The authors’ objectives were to examine the survival trajectory of crown margin repairs and to determine the factors associated with survival.MethodsRecords of adult patients from January 2008 through August 2019 were reviewed for crown margin repairs completed at University of Iowa College of Dentistry. A total of 1,002 crown margin repairs were found. Each repair was followed through the end of study in 2019 or until an event (for example, additional repair, endodontic treatment, crown replacement, or extraction). A Cox proportional hazards model was used to study the relationship between selected covariates and time to event.ResultsDuring the follow-up period, 32.8% of the repairs needed reintervention. In the final model, repair material was the only significant covariate. No difference was found between the survival of repairs done with resin-modified glass ionomer and amalgam. However, the repairs done with resin-based composite and conventional glass ionomer were more likely (1.5 times: 95% CI, 1.02 to 2.10 times; and 2 times: 95% CI, 1.40 to 2.73 times, respectively) to need reintervention than were those done with amalgam.ConclusionsMedian survival time of crown margin repairs was 5.1 years (95% CI, 4.48 to 5.72 years). Median survival times for amalgam, resin-modified glass ionomer, resin-based composite, and glass ionomer repair materials were 5.7 years (95% CI, 4.80 to 6.25 years), 5.3 years (95% CI, 4.73 to 6.34 years), 3.2 years (95% CI, 2.51 to 6.19 years), and 3.0 years (95% CI, 2.53 to 3.62 years), respectively.Practical ImplicationsWhen considering crown margin repairs, resin-modified glass ionomer or amalgam is preferable to resin-based composite or glass ionomer.  相似文献   
5.
《Cirugía espa?ola》2023,101(2):116-122
IntroductionMetastasis is remaining one of the major problems in cancer treatment. Like many other malignancies, urogenital tumors originating from kidney, prostate, testes, and bladder tend to metastasize to the lungs.The aim of this retrospective study is to evaluate the operative results and prognosis of pulmonary metastasectomy in patients with primary urogenital tumors.MethodsThis study was approved by the local ethical committee. We retrospectively analyzed the surgical and oncological results of patients who underwent lung resections for urogenital cancer metastases in our department between 2002 and 2018. Demographic data and clinicopathological features were extracted from the medical records. Survival outcomes according to cancer subtypes and early postoperative results of VATS and thoracotomy were analyzed.Results22 out of 126 patients referred for pulmonary metastasectomy to our department had metastases from urogenital tumors. These patients consisted of 17 males and five females. Their metastasis originated from renal cell carcinoma (RCC; n = 9), bladder tumor (n = 7), testis tumors (n = 4), and prostate cancer (n = 2). There was no intraoperative complication. Postoperative complications were seen in 2 patients.ConclusionsAlthough pulmonary metastasectomy in various types of tumors is well known and documented, the data is limited for metastases of urogenital cancers in the literature. Despite the limitations of this study, we aim to document our promising results of pulmonary metastasectomy in patients with primary urogenital tumors and wanted to emphasize the role of minimally invasive approaches.  相似文献   
6.

目的:评估B超在不同性质眼后段异物大小测量中的准确性。

方法:回顾性分析2016-01/12在我院被诊断为眼后段异物的患者13例13眼。异物在取出后用直尺测量实际大小,并同术前B超所测数值进行比较,同时计算相关系数(B超测量值/实际大小)。为了排除手术操作损伤异物对真实大小测量的影响,选定长度为5mm的不同材质物体(分别为金属、玻璃和木质)放入直径约20~30mm的水囊中模拟眼内异物,同样进行以上的测量,测量重复4次。

结果:选取13眼内异物均经玻璃体手术完整取出,其中金属磁性异物12眼,玻璃异物1眼。12个金属异物术前B超所测长轴和实际长度的平均值分别为3.65±1.30和2.45±0.94mm,所有测量值均大于实际值(P=0.016)。相关系数的平均值为1.49。体外实验中,金属、玻璃和木质三种不同性质异物B超的平均测量值分别为6.76±0.15、6.55±0.04和6.02±0.07mm,相关系数分别为1.35、1.31和1.20。

结论:B超用于眼后段异物测量时,其所测量值会大于真实大小,尤其是对于金属和玻璃异物。因此在术中制作异物取出切口时需要进行考虑。  相似文献   

7.
Carbamazepine (CBZ)—an antiepileptic drug—belongs to Biopharmaceutics Classification System II Class. It has low solubility and consequently limited bioavailability. One of the ways to improve drugs solubility is amorphization of their structure. Herein, cooling CBZ—at different cooling rates—was investigated as a way to obtain glassy, better soluble form. During preliminary differential scanning calorimetry experiments, some peculiar behavior of the examined material, different from those stated in the literature, was observed. Further investigations using differential scanning calorimetry, thermogravimetric analysis, and polarizing optical microscope revealed that decomposition temperature of CBZ is about 30°C lower than previously assumed. Moreover, high-resolution thermogravimetric measurements indicate that some decomposition processes could start even below the temperature reported as the melting point of the form I of CBZ.  相似文献   
8.
Isolators are commonly used in filling operations of pharmaceutical products. To ensure an aseptic inner environment, isolators are regularly sterilized with vaporized hydrogen peroxide. However, despite extensive purging with air, some residual H2O2 remains within the isolator atmosphere and may thus end up in the liquid pharmaceutical drug product, which subsequently may cause oxidation and impact the product’s safety and efficacy. We aimed to evaluate the extent of this phenomenon and to model it. For that purpose, we studied the diffusion of H2O2 into water contained in small recipients exposed to the atmosphere of a H2O2-sterilized small-scale test isolator. Based on the results, a mechanistic model was proposed to estimate the quantity of H2O2 in the product, taking into account the time, filling volume, H2O2 concentration, and a configuration factor. Afterward, this model was challenged by filling water at a manufacturing scale, and we observed that the diffusion model could predict the trend of increasing H2O2 concentration. However, a consistent difference in H2O2 concentration between the model and the experimental results was observed, suggesting the contribution of another parameter. Our results can be used to predict more accurately H2O2 concentration in a pharmaceutical product at the manufacturing level.  相似文献   
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