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The mesopancreas does not have well-defined boundaries but is continuous and connected through its components with the paraaortic area. The mesopancreatic resection margin has been indicated as the primary site for R1 resection after PD in pancreatic head cancer and total mesopancreas excision has been proposed to achieve adequate retropancreatic margin clearance and to minimize the likelihood of R1 resection. However, the anatomy of the mesopancreas requires extended dissection of the paraaortic area to maximize posterior clearance. The artery-first surgical approach has been developed to increase local radicality at the mesopancreatic resection margin. During PD, the artery-first approach begins with dissection of the connective tissues around the SMA. However, the concept of the mesopancreas as a boundless structure that includes circumferential tissues around the SMA, SMV, and paraaortic tissue highlights the need to shift from artery-first PD to mesopancreas-first PD to reduce the risk of R1 resection. From this perspective the “artery-first” approach, which allows for the avoidance of R2 resection risk, should be integrated into the “mesopancreas-first” approach to improve the R0 resection rate.In total mesopancreas excision and mesopancreas-first pancreaticoduodenectomies, the inclusion of the paraaortic area and circumferential area around the SMA in the resection field is necessary to control the tumour spread along the mesopancreatic resection margin rather than to control or stage the spread in the nodal basin. 相似文献
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目的:葛根总黄酮(PTF)可治疗心脑血管疾病,但膜通透性差,口服生物利用度低。一些辅料如卡波姆、壳聚糖和羟丙基甲基纤维素可以提高口服生物利用度。传统的体外评价技术,包括大鼠肠灌流和细胞模型,不能评价PTF整体的吸收机制。方法:本研究评价辅料的黏附性及对PTF在Caco-2细胞单层模型中转运的影响。采用cDNA微阵列测定PTF和PTF+辅料给药后的Caco-2细胞的基因表达变化,从基因水平揭示辅料对PTF整体吸收的影响机制。结果:体外黏附和Caco-2细胞转运实验表明,与单独PTF相比,加入辅料后对胃黏膜具有更高的黏附性,且在Caco-2细胞模型中的转运效率更高。PTF与辅料的相互作用显著改变了某些基因的表达,可能影响PTF的吸收效率。结论:不同的生物黏附聚合物能提高PTF的肠道吸收,可能与ATP结合盒(ABC)和溶质载体转运体(SLC)的表达基因有关。 相似文献
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《Chest》2020,157(5):1322-1345
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《Neuro-Chirurgie》2022,68(2):239-242
IntroductionIndocyanine green (ICG) is commonly used to visualize cerebral vasculature, particularly in the management of cerebral aneurysms. There have also been attempts to use ICG for visualization of tumors. Injection of ICG followed by immediate fluorescence microscopy is limited by the short time window for imaging and administration and restricted depth of imaging. Second Window Indocyanine Green (SWIG) addresses these issues by allowing for longer contrast times and the imaging of deeper regions of brain tissue. Biopsy of spinal cord lesions is often difficult for a variety of reasons, including the delicate nature of the tissue and differentiating normal from lesional tissue visually, especially in lesions with heterogeneous enhancement.MethodsIn this case report, we describe the use of second window ICG to facilitate the visualization of a spinal cord lesion and subsequent biopsy of the lesion.ResultsThis patient is a 24-year-old female who had recurrence of a suprasellar germinoma. An MRI of the rest of the neuraxis was performed to assess for the presence of drop metastases. The spinal cord from C2-5 was expanded with areas of patchy enhancement; however, this lesion was asymptomatic. The patient's oncologist requested a biopsy of this lesion to help direct subsequent care of her recurrent germinoma. The day before surgery, the patient had an intravenous injection of ICG dye. She then underwent a C3-5 laminectomy for biopsy of her cervical intramedullary lesion. After opening of the dura, no visible abnormality of the spinal cord could be identified. A Stryker endoscope showed an area of ICG uptake in the cord at approximately the C3-4 level. A midline myelotomy was centered over the ICG demarcated area and several samples were taken for pathology. Final biopsy results determined the lesion to be spinal cord parenchyma with perivascular and intraparenchymal lymphocytes – not consistent with spinal cord tumor or germinoma.ConclusionSecond Window ICG is effective in visualizing otherwise visually unremarkable spinal cord lesions. This technology can facilitate biopsy of these lesions and possibly their surgical resection. 相似文献