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991.
992.
The concept of differential regulation of certain adhesion molecules on different cell subsets and their relevance to cell functions has emerged in recent years. The initial event in bone remodeling is an increase in osteoclastic bone resorption and cell adhesion between osteoclastic precursors and bone marrow stromal cells or osteoblasts is known to commit the osteoclast development. Here, we show that human osteoblasts can be divided into two subsets based on the expression of the intercellular adhesion molecule (ICAM)-1; ICAM-1+ osteoblasts highly adhered to monocytes, including osteoclast precursors, produced osteoclast differentiation factor (ODF), and induced multinuclear osteoclast-like cell formation. Anti-ODF monoclonal antibody (mAb) did not inhibit the adhesion of monocytes to osteoblastic cells, whereas anti-leukocyte function-associated antigen (LFA)-1, a receptor for ICAM-1, mAb blocked the adhesion. We thereby propose that the higher affinity adhesion via LFA-1/ICAM-1 is prerequisite for efficient function of membrane-bound ODF during osteoclast maturation. The functional characteristics of ICAM-1+ osteoblasts were emphasized further by cell cycle regulation, as manifested by (i) up-regulation of p53 and p21, (ii) reduction of activity of cyclin-dependent kinase (cdk) 6, (iii) underphosphorylation of retinoblastoma protein, (iv) increased Fas but reduced bcl-2 expression, and (v) majority of cells remained at G0/G1 phase. Furthermore, ICAM-1+ osteoblasts were induced by interleukin-1beta (IL-1beta). Taken together, we propose that the differentiation of osteoblasts to ICAM-1+ subpopulation by inflammatory cytokines plays an important role in osteoporosis, which is observed in patients with chronic inflammation, because ICAM-1+ osteoblasts can bias bone turnover to bone resorption, committing osteoclast maturation through cell adhesion with its precursor, and the majority of ICAM-1+ osteoblasts arrested at G0/G1 phase. Such regulation of cell cycle arrest also is an important determinant of the life span of cells in bone in which continuous bone remodeling maintains its homeostasis.  相似文献   
993.
Primary osteosarcoma of heart with severe congestive heart failure.   总被引:5,自引:0,他引:5  
We present a case report on a 54-year-old woman with extraskeletal osteosarcoma of the left atrium featuring severe congestive heart failure. We resected the tumor, which occupied the left atrium and had widely infiltrated the atrial wall, but the patients died of the tumor 9 months after surgery. This is to our knowledge the 32nd case of cardiac osteosarcoma ever reported.  相似文献   
994.
In recent years, imaging tumors with receptor-specific biomolecules has been the focus of increasing interest. Vasoactive intestinal peptide (VIP) has a high affinity for specific receptors that are expressed in high density on a large number of malignant tumors. VIP was modified (TP 3654) without compromising its biologic activity and labeled with 99mTc. Pharmacokinetics and feasibility studies were performed in 3 healthy volunteers and 11 patients with a history of cancer. Imaging was performed for up to 2 h after injection. Within 24 h after injection of 99mTc-TP 3654 (370-555 MBq/5 microg), approximately 70% of the tracer cleared through the kidneys and 20% through the liver. Blood clearance was rapid. No adverse reaction was noted in any subject. All known tumors were clearly delineated within 20 min. Findings were compared with the results of 99mTc-methoxyisobutyl isonitrile, CT, MRI, or histology. There was concordance in 9 patients. In the other 2 patients, only the VIP scan was positive for tumors known to express VIP receptors. The early results of imaging tumors with 99mTc-VIP are promising and warrant further study.  相似文献   
995.
996.
Two cases of solid papillary carcinoma of the breast were pathologically studied. Subjects included two female patients: a 76-year-old (Case 1) and a 43-year-old (Case 2). Both cases showed solid and papillary proliferation of spindle cells in expanded ducts, perivascular pseudorosettes, eosinophilic fine granules in an abundant cytoplasm, intracellular mucin production, and positivity for chromogranin A. Case 1 showed an aggregation form involving multiple ducts, admixture of signet-ring like cells, mucin pools, and small and large electron-dense granules and flocculent granules in electron microscopy. Case 2 showed a solitary and compact form in a dilated duct and an interlacing bundle pattern.  相似文献   
997.
998.
999.
Leg malperfusion caused by dynamic obstruction is a serious complication of aortic dissection. A diagnosis of the malperfusion is difficult because it is made mainly on the basis of nonspecific symptoms such as intermittent claudication and numbness on walking. In the present study, we reported on a case of a 51‐year‐old man with leg malperfusion in chronic aortic dissection diagnosed by Doppler ultrasound. The combination of bisferious and dampened velocity waveform changes after walking may lead us to suspect a leg malperfusion caused by dynamic obstruction.  相似文献   
1000.
The incidence of postoperative SSI (surgical site infection) after hepatic resection has decreased gradually with the refinement of surgical techniques and perioperative management. However, postoperative SSI still develops in a few patients after hepatic resection, leading to increased medical costs, longer hospitalization and a reduced quality of life in the postoperative course. The purpose of this study was to analyze the risk factors of SSI and to assist in predicting the occurrence of SSI after hepatic resection. A retrospective analysis of 227 patients who underwent hepatic resection without biliary reconstruction for liver disease between January 2006 and December 2012 was performed. Patients were divided into two groups according the occurrence of SSI. The association between SSI and various clinical parameters was investigated. Nineteen patients developed SSI: 9 with superficial or deep SSI and 10 with organ/space SSI. In univariate analysis, preoperative platelets, aspartate aminotransferase and alanine aminotransferase concentrations, intraoperative blood loss, perioperative transfusion, procedure of skin closure, and postoperative bile leakage differed statistically between the two groups. Patients with SSI required significantly longer hospitalization than those without SSI. In multivariate analysis, conventional skin closure and postoperative bile leakage were the significant risk factors. It is important to prevent bile leakage to reduce postoperative SSI. Moreover, subcuticular suture for skin closure would be effective in preventing incisional SSI. Continuous efforts should be made to prevent SSI and further study is needed to develop additional new strategies for preventing SSI.  相似文献   
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