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991.
Cognitive Therapy and Research - Increased overgeneral categoric memory has been reported in individuals with dysphoria and a history of depression. In three experiments, we examined whether...  相似文献   
992.
Stenosing flexor tenosynovitis, trigger finger, is a common clinical disorder causing painful locking or contracture of the involved digits, and most instances are idiopathic. This problem is generally caused by a size mismatch between the swollen flexor tendon and the thickened first annular pulley. Although hypertrophic pulleys have been histologically and ultrasonographically detected, little is known about the histopathology of the tenosynovium covering the tendons of trigger fingers. We identified chondrocytoid cells that produced hyaluronic acid in 23 (61%) fingers and hypocellular collagen matrix in 32 (84%) fingers around the tenosynovium among 38 specimens of tenosynovium from patients with trigger fingers. These chondrocytoid cells expressed the synovial B cell marker CD44, but not the chondrocyte marker S‐100 protein. The incidence of these findings was much higher than that of conventional findings of synovitis, such as inflammatory infiltrate (37%), increased vascularity (37%), hyperplasia of synovial lining cells (21%), or fibrin exudation (5%). We discovered the following distinctive histopathological features of trigger finger: hyaluronic acid‐producing chondrocytoid cells originated from fibroblastic synovial B cells, and a hypocellular collagen matrix surrounding the tenosynovium. Thus, an edematous extracellular matrix with active hyaluronic acid synthesis might increase pressure under the pulley and contribute to the progression of stenosis.  相似文献   
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Purpose

Pulmonary hypoplasia (PH), characterized by alveolar immaturity, remains the main cause of neonatal mortality and long-term morbidity in infants with congenital diaphragmatic hernia (CDH). Lipid-containing interstitial fibroblasts (LIFs) are critically important for normal alveolar development. Thymocyte antigen 1 (Thy-1) is a highly expressed cell-surface protein in this specific subset of lung fibroblasts, which plays a key role in fetal alveolarization by coordinating the differentiation and lipid homeostasis of alveolar LIFs. Thy-1 increases the lipid content of LIFs by upregulation of adipocyte differentiation-related protein (ADRP), a lipogenic molecular marker characterizing pulmonary LIFs. Thy-1 ?/? mice further show impaired alveolar development with reduced proliferation of pulmonary LIFs, resulting in a PH-similar phenotype. We hypothesized that pulmonary Thy-1 signaling is disrupted in experimentally induced CDH, which may has an adverse effect on the lipid content of alveolar LIFs.

Methods

Timed-pregnant Sprague–Dawley rats were treated with either 100 mg nitrofen or vehicle on embryonic day 9.5 (E9.5). Fetuses were killed on E21.5, and lungs were divided into controls (n = 14) and CDH-associated PH (n = 14). Pulmonary gene expression levels of Thy-1 and ADRP were assessed by quantitative real-time PCR. ADRP immunohistochemistry and oil-red-O staining were used to localize alveolar LIF expression and lipid droplets. Immunofluorescence double staining for Thy-1 and oil-red-O was performed to evaluate Thy-1 expression and lipid content in alveolar LIFs.

Results

Radial alveolar count was significantly reduced in CDH-associated PH with significant downregulation of pulmonary Thy-1 and ADRP mRNA expression compared to controls. ADRP immunoreactivity and lipid droplets were markedly diminished in alveolar interstitial cells, which coincided with decreased alveolar LIF expression in CDH-associated PH compared to controls. Confocal laser scanning microscopy confirmed markedly decreased Thy-1 expression and lipid content in alveolar LIFs of CDH-associated PH compared to controls.

Conclusion

Our study provides strong evidence that disruption of pulmonary Thy-1 signaling results in reduced lipid droplets in alveolar LIFs and may thus contribute to PH in the nitrofen-induced CDH model. Treatment modalities aimed at increasing lipid content in alveolar LIFs may therefore have a therapeutic potential in attenuating CDH-associated PH.  相似文献   
996.
The epicardium, which is derived from the proepicardial organ (PE) as the third epithelial layer of the developing heart, is crucial for ventricular morphogenesis. An epicardial deficiency leads to a thin compact layer for the developing ventricle; however, the mechanisms leading to the impaired development of the compact layer are not well understood. Using chick embryonic hearts, we produced epicardium‐deficient hearts by surgical ablation or blockade of the migration of PE and examined the mechanisms underlying a thin compact myocardium. Sarcomeric maturation (distance between Z‐lines) and cardiomyocyte growth (size) were affected in the thin compact myocardium of epicardium‐deficient ventricles, in which the amounts of phospho‐smad2 and phospho‐ERK as well as expression of transforming growth factor (TGF)β2 and fibroblast growth factor (FGF)2 were reduced. TGFβ and FGF were required for the maturation of sarcomeres and growth of cardiomyocytes in cultured ventricles. In ovo co‐transfection of dominant negative (dN)‐Alk5 (dN‐TGFβ receptor I) and dN‐FGF receptor 1 to ventricles caused a thin compact myocardium. Our results suggest that immature sarcomeres and small cardiomyocytes are the causative architectures of an epicardium‐deficient thin compact layer and also that epicardium‐dependent signaling mediated by TGFβ and FGF plays a role in the development of the ventricular compact layer before the onset of coronary circulation.  相似文献   
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Laparoscopic pancreatic surgery is one of the most difficult procedures, and the adoption of laparoscopic pancreaticoduodenectomy has been limited. The application of laparoscopic surgery has extended to advance cancer, but there have been no reports of laparoscopic pancreaticoduodenectomy after laparoscopic liver resection and distal pancreatectomy. In the present case, a 67‐year‐old woman was diagnosed with remnant pancreatic recurrence of metastatic greater omentum leiomyosarcoma. She had previously undergone laparoscopic distal pancreatectomy and left lateral liver sectionectomy in 2016. We performed laparoscopic subtotal stomach‐preserving pancreaticoduodenectomy in June 2017. The operation time was 274 minutes, and the estimated blood loss was 50 mL. There were no postoperative complications. In summary, laparoscopic pancreaticoduodenectomy is a safe and feasible procedure for a patient who had previously undergone pancreas and liver surgery.  相似文献   
1000.
Robot‐assisted surgery has advanced rapidly since the 1980s. However, new equipment is still needed to overcome problems in conventional endoscopic surgery, including unique risks, such as camera shake and communication difficulties between the operator and the scopist. EMARO, an endoscope manipulator robot, is the world's first pneumatically driven endoscope‐holder robot that can operate flexibly and smoothly with the use of air pressure. We herein report the surgical experience of using EMARO in totally extraperitoneal inguinal hernia repair. A 77‐year‐old Japanese man presented with bulging in the right groin area. After we diagnosed a right inguinal hernia, endoscopic inguinal hernia repair was performed. We selected the totally extraperitoneal approach with EMARO. The endoscopic procedure time was 100 minutes, and no intraoperative complications occurred. EMARO brings together features of smooth motion and good manipulation performance. This operation was performed safely and was comparable to a conventional operation completed with human assistants. Solo surgery with EMARO was beneficial in this inguinal hernia patient.  相似文献   
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