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101.
Y I Kim  E S Yu  K W Lee  E U Park  H G Song 《Cancer》1987,60(11):2785-2790
Among the rare occurrences of primary malignant mesenchymal tumors of the liver, the development of liposarcoma has been only theoretically listed--there is no proven example in the literature. This article documents a case of primary liposarcoma of the liver in a 30-year-old woman who presented with a huge intrahepatic tumor in the left lobe measuring 14 X 10 X 6 cm. It was composed of two distinct macroscopic and histologic features--the well-differentiated liposarcoma and the cellular, nonlipogenic pleomorphic sarcoma. The former was a mature, lipomatous tumor with various stages of lipoblasts. The latter was much more cellular, made up of pleomorphic cells admixed with a few areas of spindle cells with many mitotic figures, resembling a pleomorphic variant of malignant fibrous histiocytoma. Oil red O stain revealed multifocal, but a scanty amount, of fat-storing tumor cells in both compartments aside from large fat globules in the differentiated area. This is the first reported case of primary liposarcoma of the liver.  相似文献   
102.
本文以大鼠为实验对象,观察了γ线8Gy照后胃组织内乙酰胆碱含量、胆碱酯酶活性及平滑肌对乙酰胆碱反应性的变化。结果表明,照后1/24~l天胃组织内乙酰胆碱含量明显下降,3天趋向正常,5天基本恢复至照前水平。胃组织的胆碱酯酶活性在照后l/24~5天基本无改变。在同一剂量照后1h,胃窦平滑肌对乙酰胆碱的反应与照前近似,l天后开始减弱,3天后明显下降,与正常相比有非常显著差异。  相似文献   
103.
Lymphomatoid granulomatosis (LG) is a potentially malignant lymphoproliferative disorder. The lung is the most common involved site, followed by the skin and nervous system. However, LG of the central nervous system presenting with Parkinsonism is very rare. We report a patient with LG who presented with parkinsonian features such as bilateral rigidity, bradykinesia, and agitation. Brain magnetic resonance imaging showed multifocal punctuate enhanced lesions in both supra- and infratentorial areas. Steroid pulse therapy resulted in a dramatical improvement in the symptoms and MRI abnormalities.  相似文献   
104.
螺旋CT三维重建影像在胫骨平台骨折诊疗中的价值   总被引:12,自引:0,他引:12  
目的探讨螺旋CT三维重建影像在胫骨平台骨折诊断和治疗中的临床使用价值。方法2001年8月~2005年4月收集38例胫骨平台骨折分别行X线片和螺旋CT三维重建影像检查,对照术中所见,分析比较螺旋CT三维重建影像在临床诊断和治疗中的作用。结果X线片检查2例无法明确诊断,骨折分型错误6例;螺旋CT三维重建诊断、分型均正确。X线片与螺旋CT三维重建影像在确立诊断方面未见明显差异,但在分型和指导治疗方面,螺旋CT三维重建影像明显优于前者。结论螺旋CT三维重建影像能直观、立体地显示胫骨平台骨折的形态,有助于骨折的分型及治疗。  相似文献   
105.
Paget's disease is a focal condition of bone. To study changes in cells within pagetic lesions, we cultured osteoblasts and stromal cells from 22 patients and compared gene expression in these cells to cells from healthy bone. We identified several differentially regulated genes, and we suggest that these changes could lead to the formation of the lesions. INTRODUCTION: Paget's disease is a focal condition of bone of unknown cause. Although it is regarded as primarily an osteoclast disorder, the tight coupling of the activity of osteoclasts and osteoblasts suggests that the osteoblast could play a key role in its pathogenesis. The aim of the study was to identify possible changes in pagetic osteoblasts and stromal cells that might contribute to the development of pagetic lesions. MATERIALS AND METHODS: Candidate genes were identified based on known bone cell regulators, supplemented with microarray analysis. Gene expression was determined by real-time PCR in primary cultures of osteoblasts and bone marrow stromal cells from pagetic patients and control subjects. Concentrations of secreted proteins were determined by ELISA. RESULTS: Dickkopf1 mRNA and protein levels were increased in both pagetic osteoblast and stromal cell cultures, and interleukin (IL)-1 and IL-6 were overexpressed in pagetic osteoblasts. These changes parallel recent findings in myeloma bone disease, which shares some clinical similarities with Paget's disease. Alkaline phosphatase was overexpressed, and bone sialoprotein and osteocalcin were underexpressed in pagetic osteoblasts, consistent with their circulating levels in pagetic patients. It is hypothesized that overexpression of Dickkopf1, IL-1, and IL-6 would result in stimulation of osteoclast proliferation and inhibition of osteoblast growth, leading to the development of the characteristic lytic bone lesions. By stimulating osteoblast differentiation, Dickkopf1 and IL-6 may also promote mineralization, leading to the conversion of lytic lesions to sclerotic. CONCLUSIONS: These findings suggest that dysregulated gene expression in pagetic osteoblasts could cause the changes in bone cell number and function characteristic of Paget's disease.  相似文献   
106.
Studies have shown that systemic PTH treatment enhanced the rate of bone repair in rodent models. However, the mechanisms through which PTH affects bone repair have not been elucidated. In these studies we show that PTH primarily enhanced the earliest stages of endochondral bone repair by increasing chondrocyte recruitment and rate of differentiation. In coordination with these cellular events, we observed an increased level of canonical Wnt-signaling in PTH-treated bones at multiple time-points across the time-course of fracture repair, supporting the conclusion that PTH responses are at least in part mediated through Wnt signaling. INTRODUCTION: Since FDA approval of PTH [PTH(1-34); Forteo] as a treatment for osteoporosis, there has been interest in its use in other musculoskeletal conditions. Fracture repair is one area in which PTH may have a significant clinical impact. Multiple animal studies have shown that systemic PTH treatment of healing fractures increased both callus volume and return of mechanical competence in models of fracture healing. Whereas the potential for PTH has been established, the mechanism(s) by which PTH produces these effects remain elusive. MATERIALS AND METHODS: Closed femoral fractures were generated in 8-wk-old male C57Bl/6 mice followed by daily systemic injections of either saline (control) or 30 microg/kg PTH(1-34) for 14 days after fracture. Bones were harvested at days 2, 3, 5, 7, 10, 14, 21, and 28 after fracture and analyzed at the tissue level by radiography and histomorphometry and at the molecular and biochemical levels level by RNase protection assay (RPA), real-time PCR, and Western blot analysis. RESULTS: Quantitative muCT analysis showed that PTH treatment induced a larger callus cross-sectional area, length, and total volume compared with controls. Molecular analysis of the expression of extracellular matrix genes associated with chondrogenesis and osteogenesis showed that PTH treated fractures displayed a 3-fold greater increase in chondrogenesis relative to osteogenesis over the course of the repair process. In addition, chondrocyte hypertrophy occurred earlier in the PTH-treated callus tissues. Analysis of the expression of potential mediators of PTH actions showed that PTH treatment significantly induced the expression of Wnts 4, 5a, 5b, and 10b and increased levels of unphosphorylated, nuclear localized beta-catenin protein, a central feature of canonical Wnt signaling. CONCLUSIONS: These results showed that the PTH-mediated enhancement of fracture repair is primarily associated with an amplification of chondrocyte recruitment and maturation in the early fracture callus. Associated with these cellular effects, we observed an increase in canonical Wnt signaling supporting the conclusion that PTH effects on bone repair are mediated at least in part through the activation of Wnt-signaling pathways.  相似文献   
107.
目的:制备结合凝血酶原复合物(PCC)的阴离子脂膜微泡,评价微泡的理化性质。材料和方法:采用机械振荡直接连接法,分两组(于机械振荡之前或之后加入),制备结合PCC的阴离子脂膜微泡,观察并检测洗涤前后微泡的理化性质。结果:微泡与PCC的结合率及Ⅸ因子活性:两组间比较无明显差异(P>0.05),但洗涤后结合率由洗涤前的95%降为80%,活性由90%降为19%。结论:直接连接法可制备结合PCC的阴离子脂膜微泡,微泡与PCC结合率较高,且洗涤前能保持Ⅸ因子较高的活性。  相似文献   
108.
BACKGROUND: Epinephrine injected by an autoinjector in the anterolateral aspect of the thigh is the standard of care in the emergency self-treatment of anaphylaxis. In the United States, the autoinjector EpiPen is widely used for the self-treatment of anaphylaxis. OBJECTIVE: To investigate whether EpiPen autoinjector, with a needle length of 1.43 cm, is sufficient for intramuscular delivery of epinephrine in men and women. METHODS: The distance from skin to muscle in the anterolateral aspect of the thigh was measured in 50 men and 50 women who had undergone computed tomography of the thighs for other medical reasons. For each individual, body mass index (BMI; a measure of weight in kilograms divided by the square of height in meters) was also calculated, and the individuals were classified as underweight (BMI, < 18.5), normal (BMI, 18.5-24.9), overweight (BMI, 25.0-29.9), and obese (BMI, > or = 30.0) using standard definition. RESULTS: In the study participants the mean +/- SD distance from skin to muscle was 0.66 +/- 0.47 cm for men and 1.48 +/- 0.72 cm for women (P < .001). One man (obese at a BMI of 42.2) and 21 women (11 obese with a mean BMI of 35.2, 6 overweight with a mean BMI of 30.1, and 4 normal with a mean BMI of 24.5) had a greater distance from skin to muscle than the EpiPen needle length of 1.43 cm. CONCLUSION: The distance from skin to muscle for the anterolateral aspect of the thigh is higher in women compared with men. This difference suggests that EpiPen may not deliver epinephrine to the intramuscular tissue in many women.  相似文献   
109.
王松  叶智荣  陈达和 《西部医学》2006,18(4):460-461
目的观察曲马多、氟哌利多在剖宫产手术中预防寒战的效果。方法选择60例A SAⅠ、Ⅱ级剖宫产孕妇,无其它并发症,随机分为3组:曲马多组、氟哌利多组、生理盐水组。胎儿取出后从静脉分别注入曲马多1.0~1.50m g/kg,氟哌利多0.05m l/kg,生理盐水2m l,观察预防寒战的效果。结果寒战发生率及程度为:曲马多组:1级1例,2级1例,占10.0%;氟哌利多组:1级3例,2级3例,3级1例,占35.0%;生理盐水组:1级3例,2级2例,3级3例,占40.0%。后两组与曲马多组比较,差异有统计学意义(P=0.026)。讨论剖宫产手术患者术中应用曲马多能有效减少寒战的发生率,减轻患者的不舒适性,氟哌利多作用不明显。  相似文献   
110.
OBJECTIVE: To conduct a systematic review to gather the available evidence on the optimum timing of the radiotherapy in relation to autologous breast reconstruction. MATERIAL AND METHODS: The data was extracted from scientific databases, and a manual follow-up of references. The studies were selected which included at least 20 patients with any method of autologous breast reconstruction who were treated with adjuvant radiotherapy either before or after their reconstruction, and had addressed the effects of radiotherapy on the cosmetic outcome in their results. The principal outcome was cosmetic appearance. Secondary outcomes were immediate and delayed complications. RESULTS: We could not find any randomised controlled trial on this topic. Ten studies were included, most were retrospective, heterogeneous in terms of control groups, radiation doses, follow-up duration, and outcome measurements. Two studies included no control groups, and four studies compared the outcomes of patients with radiotherapy either before (n=3) or after (n=1) autologous breast reconstruction. The overall incidence of complications was increased in patients with radiotherapy in three out of these four studies. Only four studies directly compared the outcomes of patients who received radiotherapy before with patients who received radiotherapy after autologous breast reconstruction and two out of these reported worse outcomes associated with post-reconstruction radiotherapy. CONCLUSIONS: Despite the paucity of the published data, the current evidence suggests that the radiation has a deleterious effect on autologous flap reconstruction. Until better methods of radiation delivery can be devised to minimise the long term radiation sequelae in the irradiated tissue, delayed reconstruction seems to be a safe option in most of the cases. However, the findings from these studies should be interpreted with great caution before generalising from their results.  相似文献   
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