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1.
We describe the enhancement patterns of myoepithelioma in two patients with a soft palate mass. In the first case, helical CT revealed a faintly enhancing mass. Histologically, the tumor was composed of plasmacytoid cells in a background of rich myxoid stroma. Immunostaining for CD34 showed scanty blood vessels. In the second case, helical CT revealed an intensely enhancing mass. Histologically, the mass was a cellular tumor with fibrous stroma. Immunostaining for CD34 also showed frequent blood vessels. 相似文献
2.
Ischemic necrosis of the entire femoral head and rapidly destructive hip disease: potential causative relationship 总被引:6,自引:0,他引:6
Kyung Nam Ryu Eui Jong Kim Myung Chul Yoo Yong Koo Park David J. Sartoris Donald Resnick 《Skeletal radiology》1997,26(3):143-149
Objective. Rapidly destructive hip disease (RDHD) is an uncommon disorder of the hip that has been considered a disease of unknown cause
and distinct from ischemic necrosis of the femoral head. The objective of this study was to investigate ischemic necrosis
of the femoral head as one potential cause of RDHD. Design and patients. In 600 patients who underwent MR imaging of the hip, 20 cases of ischemic necrosis involving the entire femoral head in 18
patients (3%) were retrospectively studied with routine radiography and MR imaging. All patients had surgically confirmed
ischemic necrosis of the femoral head. Results and conclusions. All patients showed rapid destruction of the femoral head on routine radiography and MR imaging as compared with the gradual
onset of clinical symptoms. Plain radiographs showed several bone fragments at the inferomedial aspect of the femoral head
(75%), acetabular erosions (55%), eccentric depression at the lateral articular surface of the femoral head conforming to
the adjacent acetabulum (35%), and mild osteoarthritis (15%). Bone sclerosis was often present at sites of impaction between
the femoral head and the acetabulum. MR imaging showed marked distention of the joint capsule in all cases. In 14 of 20 cases,
the contents of the joint space showed predominantly low or intermediate signal intensity on T1- and T2-weighted images. Ischemic
necrosis involving the entire femoral head may represent one of the causes of RDHD. 相似文献
3.
Tun Li Myung G. Lee Win L. Chiou 《Journal of pharmacokinetics and pharmacodynamics》1986,14(5):495-509
Effects of differences in the rate and composition of intravenous fluid replacement for urine loss on the pharmacokinetics and pharmacodynamics of furosemide were evaluated using the dog as a model animal. Each of six dogs received 8-hr constant intravenous infusion of 20 mg (15 mg used in one dog) of furosemide with 0% replacement (treatment I), 50% replacement (treatment II), and 100% replacement (treatment III) with lactated Ringer's solution, as well as with 100% replacement with 5% dextrose in water (treatment IV). Most pharmacokinetic parameters, such as plasma clearance, steady-state volume of distribution, mean residence time, and terminal half-life, were essentially the same in all four treatments. Renal clearances and urinary excretion rates of the drug in treatments II–IVwere essentially the same, but about 20% higher than those in treatment I.In spite of the similarities in kinetic properties, diuretic and/or natriuretic effects from furosemide were markedly different among the four treatments. For example, mean 10-hr urine outputs were 646, 1046, 3156, and 1976 ml and mean 10-hr sodium excretions were 87.0, 142, 383, and 97.2 mmole for treatments I–IV,respectively. Except for treatment III,diuresis and/or natriuresis were found to be time-dependent, generally decreasing with time until reaching a low plateau during later hours of infusion. The present findings also showed that (1)no fluid replacement and 100% replacement with 5% dextrose solution both produced the same degree of severe acute tolerance in natriuresis, indicating the insignificance of water compensation in tolerance development; (2)in treatment II,where neutral sodium balance was achieved, the development of acute tolerance in diuresis and natriuresis can mainly be attributed to negative water balance under this special condition; (3)at steady state the hourly diuresis and natriuresis could differ up to about ten times between treatments. Some implications for the kinetic/dynamic relationship or modeling, in the clinical use, and in the bioequivalence evaluation of dosage forms are discussed. 相似文献
4.
Byung Hoon Han Myung Hwan Park Yong Nam Han Lin Keun Woo 《Archives of pharmacal research》1986,9(1):21-23
Over twelve alkaloids were delected in the roots ofPanax ginseng C.A. Meyer. Among them three alkaloids were isolated and were identified as N9-formylharman, ethyl β-carboline-1-carboxylate and perlolyrine on the basis of spectroscopic studies. 相似文献
5.
Surgical reinterventions following the Fontan procedure. 总被引:2,自引:0,他引:2
Matus Petko Richard J Myung Gil Wernovsky Mitchell I Cohen Jack Rychik Susan C Nicolson J William Gaynor Thomas L Spray 《European journal of cardio-thoracic surgery》2003,24(2):255-259
OBJECTIVE: The Fontan procedure is utilized as a final reconstructive procedure for patients with functional single ventricle. Short- and long-term outcomes have improved significantly, however, some patients require additional cardiac procedures following the Fontan operation. The outcomes for these reinterventions are not known. METHODS: Cardiac Surgery and Cardiac Intensive Care Unit databases at The Children's Hospital of Philadelphia were reviewed to identify all patients who underwent cardiac surgery after a previous Fontan operation between January 1, 1995 and December 31, 2001. RESULTS: During the study period, 123 procedures were performed in 71 patients. The median time from Fontan to reoperation was 3.6 years (range 0.1-20 years). Indications for reintervention included arrhythmia, cyanosis, 'failing' Fontan circulation or exercise intolerance, protein losing enteropathy, atrioventricular valve (AVV) regurgitation, and other indications. Procedures included pacemaker insertion or revision (n = 59, 48%), reinclusion of previously excluded hepatic veins (n = 16, 13%), revision to either a lateral tunnel or extra-cardiac conduit Fontan (n = 13, 11%), cardiac transplantation (n = 9, 7%), enlargement or creation of a baffle fenestration (n = 6, 5%), isolated AVV repair or replacement (n = 2, 2%), and other procedures (n = 18, 14%). There were five early and five late deaths. Hospital mortality was greatest for patients undergoing cardiac transplantation (4/9, 44%), accounting for 80% of the early deaths. CONCLUSIONS: Surgical reinterventions following the Fontan procedure may be necessary for multiple indications which result in impairment of the Fontan circulation. Most reinterventions can be performed with minimal morbidity and mortality. Survival for patients requiring cardiac transplantation following the Fontan procedure remains poor. 相似文献
6.
Mandeep R. Mehra Patricia A. Uber Ananth Prasad Robert L. Scott Myung H. Park 《American journal of transplantation》2005,5(5):1137-1140
To identify tobacco recidivism among 86 heart transplant recipients who were smokers but demonstrated compliance with a smoking cessation program pre-transplant, we used a questionnaire and randomly tested urine for nicotine and its by-products. In 36 patients, we also evaluated circulating levels of HS-CRP, homocysteine and MPV. Twenty-eight (32.5%) of 86 patients met our definition for tobacco exposure. In this cohort, 28 (32.5%) of 86 patients met our definition for tobacco exposure. Of these 28, 12 patients self-reported tobacco use and demonstrated biochemical verification; 14 patients demonstrated only biochemical evidence of significant tobacco exposure; 2 patients self-reported tobacco use but did not demonstrate biochemical positivity. Smoking cessation within 6 months of transplantation (r = 0.52) and time post-transplantation (r = 0.43) were independent predictors for recidivism of tobacco use, p < 0.01. No differences in HS-CRP, homocysteine and MPV levels were noted among the groups. Our investigation demonstrates a high rate of tobacco recidivism among heart transplant recipients, yet few admit to it. The adverse effects of tobacco do not appear to be directly modulated by an effect on athero-thrombotic risk markers. 相似文献
7.
Dong-Hyun Kim Eun-Ah Jung In-Suk Sohng Jung-Ah Han Tae-Hyung Kim Myung Joo Han 《Archives of pharmacal research》1998,21(1):17-23
Flavonoid glycosides were metabolized to phenolic acids via aglycones by human intestinal microflora producing α-rhamnosidase, exo-β-glucosidase, endo-β-glucosidase and/or β-glucuronidase. Rutin, hesperidin, naringin and poncirin were transformed to their aglycones by the bacteria producing α-rhamnosidase and β-glucosidase or endo-β-glucosidase, and baicalin, puerarin and daidzin were transformed to their aglycones by the bacteria producing β-glucuronidase, C-glycosidase and β-glycosidase, respectively. Anti-platelet activity and cytotoxicity of the metabolites of flavonoid glycosides by human intestinal bacteria were more effective than those of the parental compounds. 3,4-Dihydroxyphenylacetic acid and 4-hydroxyl-phenylacetic acid were more effective than rutin and quercetin on anti-platelet aggregation activity. 2,4,6-Trihydroxybenzaldehyde, quercetin and ponciretin were more effective than rutin and ponciretin on the cytotoxicity for tumor cell lines. We insist that these flavonoid glycosides should be natural prodrugs. 相似文献
8.
Recessive dystrophic epidermolysis bullosa (RDEB) is an uncommon and severe disorder characterised by trauma-induced blisters, intractable skin ulcers, scarring, milia, and nail dystrophy. We report the good result of both surgical release of fingers allowing spontaneous epithelisation without skin grafting and post-operative meticulous skin care without splinting, followed-up for one year. 相似文献
9.
Nichols KE Haines K Myung PS Newbrough S Myers E Jumaa H Shedlock DJ Shen H Koretzky GA 《Journal of leukocyte biology》2004,75(3):541-552
The Src-homology 2 domain-containing, leukocyte-specific phosphoprotein of 76 kDa (SLP-76) is a hematopoietic adaptor that plays a central role during immunoreceptor-mediated activation of T lymphocytes and mast cells and collagen receptor-induced activation of platelets. Despite similar levels of expression in macrophages, SLP-76 is not required for Fc receptor for immunoglobulin G (IgG; FcgammaR)-mediated activation. We hypothesized that the related adaptor SLP-65, which is also expressed in macrophages, may compensate for the loss of SLP-76 during FcgammaR-mediated signaling and functional events. To address this hypothesis, we examined bone marrow-derived macrophages (BMM) from wild-type (WT) mice or mice lacking both of these adaptors. Contrary to our expectations, SLP-76(-/-) SLP-65(-/-) BMM demonstrated normal FcgammaR-mediated activation, including internalization of Ig-coated sheep red blood cells and production of reactive oxygen intermediates. FcgammaR-induced biochemical events were normal in SLP-76(-/-) SLP-65(-/-) BMM, including phosphorylation of phospholipase C and the extracellular signaling-regulated kinases 1 and 2. To determine whether macrophages functioned normally in vivo, we infected WT and SLP-76(-/-) SLP-65(-/-) mice with sublethal doses of Listeria monocytogenes (LM), a bacterium against which the initial host defense is provided by activated macrophages. WT and SLP-76(-/-) SLP-65(-/-) mice survived acute, low-dose infection and showed no difference in the number of liver or spleen LM colony-forming units, a measure of the total body burden of this organism. Taken together, these data suggest that neither SLP-76 nor SLP-65 is required during FcgammaR-dependent signaling and functional events in macrophages. 相似文献
10.
Growth factor-dependent activation of the MAPK pathway in human pancreatic cancer: MEK/ERK and p38 MAP kinase interaction in uPA synthesis 总被引:3,自引:0,他引:3
Increased expression of the hepatocyte growth factor (HGF) receptor (c-met) and urokinase type plasminogen (uPA) correlated
with the development and metastasis of cancers. To investigate the role of HGF/c-met signaling on metastasis in cancer cells
stimulated with HGF, we examined the effects of a specific MEK1 inhibitor (PD98059) and a p38 MAP kinase inhibitor (SB203580)
on HGF-induced uPA expression in pancreatic cancer cell lines, L3.6PL and IMIM-PC2. Pretreatment of PD98059 decreased HGF-mediated
phosphorylation of extracellular receptor kinase (ERK), uPA secretion and expression of matrix metalloproteinases (MMP-2 and
MMP-9) in a dose-dependent manner. In contrast, SB203580 pretreatment increased HGF-stimulated ERK phosphorylation, uPA secretion
and expression of MMPs. SB203580 also reversed the inhibition of HGF-mediated ERK activation and uPA secretion in the PD98059-pretreated
cells. These results suggest that ERK activation by HGF might play important roles in the metastasis of pancreatic cancer
and the p38 MAPK pathway also involved in the HGF-mediated uPA secretion and metastasis by regulation of ERK pathway.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献