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Background

Studies to identify preoperative prognostic variables for pancreatic neuroendocrine tumor (PNET) have been inconclusive. Specifically, the prevalence and prognostic significance of radiographic calcifications in these tumors remains unclear.

Methods

From 1998 to 2009, a total of 110 patients with well-differentiated PNET underwent surgical resection at our institution. Synchronous liver metastases present in 31 patients (28%) were addressed surgically with curative intent. Patients with high-grade PNET were excluded. The presence of calcifications in the primary tumor on preoperative computed tomography was recorded and correlated with clinicopathologic variables and overall survival.

Results

Calcifications were present in 16% of patients and were more common in gastrinomas and glucagonomas (50%), but never encountered in insulinomas. Calcified tumors were larger (median size 4.5 vs. 2.3?cm, P?=?0.04) and more commonly associated with lymph node metastasis (75 vs. 35%, P?=?0.01), synchronous liver metastasis (62 vs. 21%, P?P?P?=?0.01) and size (P?P?=?0.04), but not in the presence of radiographic calcifications.

Conclusions

Calcifications on preoperative computed tomography correlate with intermediate grade and lymph node metastasis in well-differentiated PNET. This information is available preoperatively and supports the routine dissection of regional lymph nodes through formal pancreatectomy rather than enucleation in calcified PNET.  相似文献   
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Purpose

This article is a narrative review regarding the usage and effectiveness of introducers or catheters to facilitate tracheal intubation through a supraglottic airway (SGA) as an alternative intubation technique in normal and difficult airway management.

Sources

Relevant articles were obtained through Medline (1948-July 2011). The articles were subsequently cross-referenced for additional literature, and only articles published in English were included.

Principal findings

In this review, we consider 32 reports using the LMA Classic?, LMA Unique?, LMA ProSeal?, LMA Supreme?, AuraOnce?, and i-gel? as SGA conduits for intubation. In 13 articles, the use of an Aintree Intubation Catheter was described as an intubation introducer and resulted in high success rates in both elective and emergent situations. Eight studies used a guidewire exchange catheter technique. Although blind intubation using a guidewire resulted in a high failure rate, these studies found that using a bronchoscope improved successful intubation. Ten studies showed that insertion of a gum elastic bougie with a bronchoscope as an intubation introducer has high success rates compared with blind bougie insertion. One article described the use of a small endotracheal tube as an intermediary for tracheal intubation.

Conclusions

In failed intubation scenarios, supraglottic airways, such as the LMA Classic? or LMA ProSeal? can serve as a conduit for tracheal intubation. A number of techniques using introducers or catheters can facilitate the insertion of an adequately sized endotracheal tube, particularly guided by a bronchoscope. Usage of introducers or catheters through a supraglottic airway may be a useful alternative intubation technique in difficult airway management.  相似文献   
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A new effective surgical procedure to repair chronic ulcers called minced micrografts technique has been recently reported. The technique consists in spreading a finely minced skin sample upon the wound bed. In this study, we investigate the in vitro release of cytokines (interleukin‐6, tumor necrosis factor‐α, interleukin‐1α, and granulocyte‐colony stimulating factor), chemokines (monocyte chemoattractant protein‐1 and growth‐related oncogene‐α), and growth factors (platelet‐derived growth factor, basic fibroblast growth factor, vascular endothelial growth factor, hepatocyte growth factor, and nerve growth factor) by minced (referred to as the minced sample) vs. not minced (referred to as the whole sample) human skin biopsy samples from the same donor. Factor release in the culture medium at different time points was detected using a multiplexed protein assay. The minced sample, which could behave like the skin fragments used in vivo in the autologous minced micrografts technique, expressed higher levels of tumor necrosis factor‐α, interleukin‐1α, platelet‐derived growth factor, and basic fibroblast growth factor, and lower levels of interleukin‐6, monocyte chemoattractant protein‐1, growth related oncogene‐α, and vascular endothelial growth factor compared with the whole sample. In conclusion, mincing of healthy skin may allow appropriate regulation of the inflammatory phase of wound healing and could induce overexpression of some growth factors, which facilitates the proliferative phase of healing.  相似文献   
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Renal artery aneurysm (RAA) is a rare clinical entity with an incidence of 0.015-1%. Indications for interventional or surgical repair of RAAs are expanding aneurysms, diameter >2.5 cm, intractable renovascular hypertension, dissecting RAA, hematuria, and renal infarction after distal embolization. Interventional insertion of a stent graft as well as aortorenal bypass implantation are both low-risk procedures in simple aneurysms of the proximal renal artery. However, complex distal renal aneurysms involving several renal artery branches require not only an excellent result of vascular reconstruction, but also a surgical technique offering maximal protection for the kidney during the ischemic period. Here, we present a case of a solitary kidney with two consecutive RAAs of segmental renal artery branches (type 2 RAA). A surgical strategy including renal explantation, ex vivo renal preservation, ex vivo reconstruction of the renal artery, and renal heterotopic autotransplantation was successfully applied. The technique of ex vivo repair is a safe and effective surgical procedure in this clinical setting.  相似文献   
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