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71.
Migration inhibitory factor (MIF) is associated with multiple organ dysfunction syndrome (MODS) in patients with systemic inflammatory response syndrome (SIRS). Our purposes were to determine the serum MIF, cortisol, and tumor narcosis factor-α (TNF-α) and to investigate the influences of the balance between the levels of MIF and cortisol in patients with blunt trauma. The cortisol levels were identical between the patients with and without MODS. However, the MIF and TNF-α levels in the patients with MODS were statistically higher than those of the patients without MODS. The cortisol/MIF ratios in the patients with MODS were statistically higher than those of the patients without MODS. The results show that MIF and TNF-α play an important role together in posttraumatic inflammatory response. An excessive serum MIF elevation overrides the anti-inflammatory effects of cortisol and leads to persistent SIRS followed by MODS in blunt trauma patients.  相似文献   
72.
The medullary microenvironment of the thymus plays a crucial role in the establishment of self-tolerance through the deletion of self-reactive thymocytes and the generation of regulatory T cells. Crosstalk or bidirectional signal exchanges between developing thymocytes and medullary thymic epithelial cells (mTECs) contribute to the formation of the thymic medulla. Recent studies have identified the molecules that mediate thymic crosstalk. Tumor necrosis factor superfamily cytokines, including RANKL, CD40L, and lymphotoxin, produced by positively selected thymocytes and lymphoid tissue inducer cells promote the proliferation and differentiation of mTECs. In return, CCR7 ligand chemokines produced by mTECs facilitate the migration of positively selected thymocytes to the medulla. The cytokine crosstalk between developing thymocytes and mTECs nurtures the formation of the thymic medulla and thereby regulates the establishment of self-tolerance.  相似文献   
73.
The thymic medulla provides a microenvironment where medullary thymic epithelial cells (mTECs) contribute to the establishment of self-tolerance by the deletion of self-reactive T cells and the generation of regulatory T cells. The progression of thymocyte development critically regulates the optimum formation of the thymic medulla, as discussed in this article. Of note, it was recently identified that RANKL produced by positively selected thymocytes plays a major role in the thymocyte-mediated medulla formation. Indeed, transgenic expression of soluble RANKL increased the number of mTECs and enlarged the thymic medulla in mice. The effects of RANKL on the thymic medulla may be useful for the engineering of self-tolerance in T cells.  相似文献   
74.
Endoscopists seek to conduct more aggressive surgical procedures that surpass the limitations of existing endoscopic procedures. Endoscopic pancreatic necrosectomy and natural orifice transluminal endoscopic surgery (NOTES) are typical examples of this new trend; both are performed through the gastrointestinal wall without a skin incision. Endoscopic necrosectomy is effective for managing organized pancreatic necrosis and abscesses. The necrotic tissues are removed endoscopically by directly entering the cavity of the organized pancreatic necrosis. NOTES is a possible advance over surgical intervention, as it is a less invasive, more cosmetic, and effective procedure. There are various approaches, including the esophagus, stomach, colon, and vagina; Various procedures are possible using NOTES, such as cholecystectomy, appendectomy, full-thickness stomach resection, splenectomy, gastrointestinal (GI) anastomosis, and peritoneoscopy. The requirements for NOTES include high proficiency in endoscopic techniques, including knowledge of various devices, anatomy, and surgical procedures. Since most GI endoscopists have no surgical background, to increase the usage of NOTES, GI endoscopists should form and lead teams that include various specialists. We believe that endoscopic necrosectomy and NOTES represent a major shift in the treatment paradigm because physicians can treat beyond the gastrointestinal wall and endoscopic procedures will replace surgical treatment.  相似文献   
75.
Background/purpose  Graft survival is affected by various factors, such as preoperative state and the ages of the recipient and donor, as well as graft size. The objective of this study was to analyze the risk factors for graft survival. Methods  From September 1997 to July 2005, 24 patients who had undergone living-donor liver transplantation (LDLT) were retrospectively analyzed. Sixteen patients survived and the eight graft-loss cases were classified into two groups according to the cause of graft loss: graft dysfunction without major post-transplantation complications (graft dysfunction group; = 3), and graft dysfunction with such complications (secondary graft dysfunction group; = 5). Various factors were compared between these groups and the survival group. Results  Mean donor age was 31.9 years in the survival group and 49.2 years in the secondary graft dysfunction group (= 0.024). Graft weight/recipient standard liver volume ratios (G/SLVs) were 36.7% in the survival group, and 26.2% in the graft dysfunction group (= 0.037). The postoperative mean PT% for 1 week was 48.6% in the survival group and 38.1% in the secondary graft dysfunction group (= 0.05). Conclusions  Our surgical results demonstrated that G/SLV and donor age were independent factors that affected graft survival rates.  相似文献   
76.
77.
Background  The effect of obesity on gastrectomy in patients with gastric cancer is controversial. The degree of abdominal fat increases the technical difficulty of abdominal surgery. This study examined the effect of visceral fat on total gastrectomy and risk factors associated with the formation of pancreatic fistula. Methods  Between February 2001 and April 2007, 191 patients with gastric cancer underwent total gastrectomy. The visceral fat area (VFA) was calculated from computed tomography (CT) scans taken at the level of the umbilicus using FatScan Software. Patients were divided into high- (≥100 cm2, n = 52) and low-VFA groups (<100 cm2, n = 139), and also into high- (≥25 kg/m2, n = 47) and low-BMI groups (<25 kg/m2, n = 144). Results  Blood loss and incidence of pancreatic fistula were significantly higher in the high- than low-VFA group. However, only blood loss was significantly different between the high- and low-BMI groups. VFA, blood loss, and splenectomy were identified as significant risk factors for pancreatic fistula formation on univariate analysis, and multivariate logistic regression analysis of these factors identified VFA (p = 0.0001) and splenectomy (p = 0.0014) as significant predictors of pancreatic fistula. Conclusions  VFA is a better indicator for pancreatic fistula formation after total gastrectomy than is BMI. Lymph node dissection must be performed carefully, especially in patients with visceral fat accumulation during total gastrectomy with splenectomy.  相似文献   
78.
Pancreatic tuberculosis (TB) is a rare condition that is sometimes difficult to differentiate from pancreatic cancer or other malignancies. A 75-year-old man was admitted to our hospital because of weight loss, fever, and diarrhea. Abdominal ultrasonography and computed tomography (CT) revealed a 3-cm mass in the pancreas head with abdominal lymphadenopathy. Endoscopic retrograde cholangiopancreatography did not show pancreatic duct stenosis or dilatation, but a pancreaticobiliary fistula was demonstrated. Cytological and bacteriological examinations of the pancreatic juice and bile were negative. Endoscopic ultrasonography-guided fine needle aspiration of the mass was not diagnostic. Colonoscopic features and biopsy specimens affirmed the diagnosis of TB, and treatment with antitubercular drugs was started. The pancreatic mass disappeared within 8 weeks and the pancreaticobiliary fistula resolved.  相似文献   
79.
BACKGROUND: The spasm provocation test (SPT)is no longer widely used in patients with undiagnosed chest pain syndromes in the USA and Europe. Objectives. The clinical significance of the SPT was examined in Japan and compared with the frequency of coronary spastic angina (CSA) in institutions with and without SPT screening. METHODS AND RESULTS: Questionnaires concerning the number of cases of coronary angiography (CAG), percutaneous coronary intervention (PCI), and invasive/non-invasive SPT in 2005 were sent to members of the Japanese Circulation Society in 1,177 cardiology hospitals. Completed surveys were returned from 208 hospitals (17.7%). Non-invasive SPT was performed in only 27 hospitals (13.0%). Invasive SPT was not performed in 50 (24.0%) institutions, and performed in the remaining 158 institutions(< 10 cases/year: 29.8%, > or = 10< 50: 33.7%, > or = 50< 100: 8.7%, > or = 100: 3.8%). There was a close correlation between the number of acetylcholine/ergonovine SPTs and the number of CSA cases finally diagnosed (acetylcholine: r(2)= 0.907, ergonovine: r(2) = 0.76). There was no difference in the number/year of CAG (525+/-451 vs 513 +/-888, NS) and PCI(175+/-156 vs 144+/-225, NS) between institutions with and without SPT screening. However, the number of CSA cases (15.6+/-21.6 vs 4.2 +/-13.0, p < 0.01) and variant angina cases (3.3+/-7.2 vs 1.4+/-2.4)in hospitals with SPT screening was higher than hospitals without SPT screening. CONCLUSIONS. If Japanese cardiologists discontinue use of the SPT as in the USA and Europe, occurrence of CSA may disappear in the near future in Japan.  相似文献   
80.
The authors report the case of a 6-year-old boy with a congenital extrahepatic portosystemic venous shunt. He had hyperammonemia. The shunt was 18 mm in diameter and located between the inferior mesenteric vein and the left internal iliac vein. The flow in the shunt was very rapid. After decreasing blood flow by inflating a balloon catheter inserted into the left internal iliac vein from the femoral vein, a microcatheter was coaxially advanced to the shunt to embolize the shunt. Embolization was successfully performed with interlocking detachable coils and microcoils without any complication. This patient's hyperammonemia resolved soon after the procedure.  相似文献   
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