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We present a case exhibiting persistent joint effusion and formation of a gigantic popliteal synovial cyst 8 years after total knee joint arthroplasty. Assessment using flow cytometry revealed that both joint and cyst fluid contained abundant macrophage-phagocytosing wear particles. This finding indicates that wear particles participated in formation of the cyst through the communication between the joint cavity and cyst. Intraoperatively, prominent villous synovial proliferation was observed in both the joint and cyst, and delamination failure of the polyethylene insert was identified. Because no evidence of prosthetic loosening was found, only polyethylene insert revision and synovectomy were undertaken, resulting in a successful outcome. This case suggests that synovial cyst formation in popliteal lesions might represent a sign of wear-particle generation after total knee joint arthroplasty.  相似文献   
75.
A dual inhibitor of acetylcholinesterase (AChE) and serotonin transporter (SERT), RS-1259 (4-[1S)-methylamino-3-(4-nitrophenoxy)]propylphenyl N,N-dimethylcarbamate (fumaric acid)(1/2)salt), was newly synthesized. RS-1259 simultaneously inhibited AChE and SERT in the brain following an oral administration in mice and rats. Actual simultaneous elevation of extracellular levels of 5-HT and ACh in the rat hippocampus was confirmed by microdialysis. The compound was as effective as SERT inhibitors such as fluoxetine and fluvoxamine in a 5-hydroxytryptophan-enhancing test in mice. Spatial memory deficits in the two-platform task of a water maze in aged rats were ameliorated by RS-1259 as well as donepezil. Both RS-1259 and donepezil increased the awake episodes in the daytime electroencephalogram of rats. Although RS-1259 was weaker than donepezil in enhancing central cholinergic transmission, as observed by ACh elevation in the hippocampus and memory enhancement in aged rats, the efficacy of RS-1259 on the consciousness level, which reflects the whole activity in the brain, was almost the same as that of donepezil. These results suggest that both cholinergic and serotonergic systems are involved in maintaining brain arousal and that a dual inhibitor of AChE and SERT may be useful for the treatment of cognitive disorders associated with reduced brain activity such as in Alzheimer's disease.  相似文献   
76.
Corneal changes in magnesium-deficient rats   总被引:1,自引:0,他引:1  
Gong H  Takami Y  Kitaoka T  Amemiya T 《Cornea》2003,22(5):448-456
PURPOSE: The purpose of the current study is to investigate the cornea in magnesium (Mg) deficiency and elucidate the local function of trace elements. METHODS: After delivery, mother Wistar Kyoto rats were fed a low Mg diet containing 0.1 mg Mg/100 g diet with all other nutrients and distilled and deionized water. Infant rats were suckled by their mothers for 21 days and then fed the same Mg-deficient diet. Control mother rats were fed commercial rat pellets containing 24 mg Mg/100 g diet and all other nutrients. The corneas were examined by electron microscopy at 6 weeks of age. RESULTS: In the Mg-deficient rats, serum Mg levels were significantly lower and calcium (Ca) levels higher than in the control rats. The corneas of Mg-deficient rats showed decreased microvilli and microplicae in the epithelial cells of the most superficial layer, increased mitochondria with abnormal shapes in the basal cells in the epithelium, condensed chromatin in the nuclei of the basal cells, and high density deposits and macrophage-like cells in the subepithelium of the stroma. Mg-deficient rats had pentagonal and square endothelial cells. CONCLUSION: Since Mg2+ has biologic functions including structural stabilization of protein, nucleic acids, and cell membranes, Mg deficiency may induce changes in the corneal surface and nuclei of corneal epithelial and endothelial cells. These disturbances may interfere with protection from infections, foreign bodies, dryness, and direct exposure to air. Thus, Mg is essential for the cornea to maintain normal structure and function.  相似文献   
77.
PURPOSE: To determine whether irsogladine inhibits experimental choroidal neovascularization (CNV) induced by laser photocoagulation in pigmented rats. METHODS: Focal laser photocoagulation (argon green 50 mW, 0.04 s, 200 microm) was applied to the retinochoroid of normal Brown Norway rats. Oral administration of irsogladine (5 mg/kg/day or 50 mg/kg/day) was started 1 week before and continued for 2 weeks after laser photocoagulation. Choroidal vascular casts were made 2 weeks after laser photocoagulation and were examined with a scanning electron microscope (SEM). CNV formation was classified according to three grades and evaluated. RESULTS: Laser-induced CNV formation was significantly reduced in rats given 5 mg/kg/day (p < 0.01) or 50 mg/kg/day of irsogladine (p < 0.001). Administration of 50 mg/kg/day of irsogladine was more effective in preventing CNV formation than 5 mg/kg/day (p < 0.001). The development of the vascular bud was especially inhibited by 50 mg/kg/day of irsogladine (p < 0.001). CNVs in rats treated with 50 mg/kg/day of irsogladine looked less well developed than those in controls. There was no significant side effect of irsogladine. CONCLUSIONS: Irsogladine inhibits the development of experimental CNV induced by photocoagulation in pigmented rats.  相似文献   
78.
OBJECTIVES: A minilaparotomy approach (skin incision less than 7 cm) to resection of colon cancer is technically feasible, but objective data supporting its benefit are scarce. The aim of this study was to clarify whether minilaparotomy is independently associated with a reduction in the acute inflammatory response after resection of colorectal cancer. DESIGN: Thirty-one patients who underwent surgical resection of colorectal cancer using minilaparotomy or conventional laparotomy were included in this nonrandomized prospective study. Inflammatory responses were evaluated with serum interleukin-6 (IL-6) and C-reactive protein (CRP) levels. RESULTS: In both the minilaparotomy and conventional laparotomy groups, serum IL-6 and CRP levels significantly increased 24 h after the operation (1POD) compared to preoperative levels (p < 0.0001 and p < 0.0001, respectively). Median serum levels of IL-6 and CRP in the minilaparotomy group were significantly lower at 1POD versus the conventional group (p = 0.0066 and p = 0.0033, respectively). Multivariate analyses showed that a smaller increase in serum IL-6 or CRP levels at 1POD [less than 75th percentile (112.9 or 10.6 mg/ml, respectively)] was independently related to only minilaparotomy. CONCLUSIONS: These data in this nonrandomized trial suggest that minilaparotomy may be independently associated with reduced inflammatory responses in colorectal cancer resection.  相似文献   
79.
PURPOSE: The purpose of this study was to clarify whether or not preoperative serum levels of interleukin-6 (IL-6) correlate with well-established prognostic variables (serum level of carcinoembryonic antigen (CEA), stage, histological grade, lymphatic and venous invasion) in colorectal cancer patients. PATIENTS AND METHODS: Serum levels of IL-6 and CEA were determined in 62 patients who underwent resection of colorectal cancer. The patients were divided into two groups based on a selected cut-off value: high and low IL-6 and CEA groups. RESULTS: The median serum level of IL-6 in colorectal cancer patients was significantly higher than the median level in normal controls (p = 0.0014). Multivariate logistic regression analysis showed that a high serum level of CEA is an independent predictor for a high serum level of IL-6 (odds ratio, 4.10; p = 0.046). CONCLUSION: A high serum level of IL-6 is significantly associated with a high serum level of CEA in preoperative colorectal cancer patients.  相似文献   
80.
We reported the "Doctor-Heli" (medical service helicopter) system at the center of emergency and critical care medicine at Tokai University Hospital. From October 1999 to March 2001, the service had transported 485 patients, shortening the time to critical care and improving patient-prognosis. We report a case of cervical and laryngeal trauma occurring during a suicide attempt successfully treated thanks to the rapid start of critical care enabled by use of the helicopter. The service has proven its utility in otolaryngology and head and neck surgery.  相似文献   
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