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排序方式: 共有801条查询结果,搜索用时 15 毫秒
81.
Hepatoid adenocarcinoma (HAC) is a special type of extrahepatic adenocarcinoma, which has a striking morphologic similarity to hepatocellular carcinoma. Seven HACs arising in the stomach and one in the lung, all with liver metastasis, were studied. They shared clinical features, such as old age, high serum alpha-fetoprotein level, aggressive behavior, and hepatic tumor in absence of risk factors for hepatocellular carcinoma (HCC). Morphologically, tumors were characterized by an admixture of tubulo-and/or papillary adenocarcinoma with hepatoid foci. In six cases, liver metastases showed an exclusive hepatoid differentiation, virtually indistinguishable from HCC with solid growth pattern. As HAC and HCC cannot be differentiated on the basis of morphology alone, differences in immunohistochemical reaction patterns would be of considerable diagnostic help. Immunostaining for CK7, CK8, CK18, CK19, CK20, alpha-fetoprotein, p-CEA, and HepPar1 revealed that hepatoid areas of both primary and metastatic HAC have a specific immunoprofile, distinctive of this entity. On the one hand, positivity of virtually all HACs for alpha-fetoprotein, CK8, CK18, and the membranous, canalicular staining for polyclonal carcinoembryonic antigen underline its hepatoid nature. On the other hand, positive staining for CK19 and CK20 and frequent negativity for HepPar1 in both primary tumors and their metastases were distinctive features of HAC. Furthermore, HAC differs from combined hepatocellular cholangiocarcinoma, being negative for CK7. In addition, for comparison of immunohistochemical results, we stained with the same antibody panel a tissue microarray of 121 HCCs. Comparative genomic hybridization study of three HAC supports their hepatoid differentiation as aberrations found in HAC are common in HCC (4q-, 8p-), and hepatoblastoma (Xq+), respectively.  相似文献   
82.
PURPOSE: The purpose of this study was to determine whether an ultra-endurance event is a strong stimulus to increase albumin synthesis involved in the process of intravascular albumin mass increase associated with transient hypervolemia. METHODS: The albumin synthetic rate was measured in six young men, 3 d before (C) and on the 1st (R1) and 8th (R8) days of the recovery from an ultra-endurance trial (5 h daily for 4 d). Albumin fractional (FSR) and absolute (ASR) synthetic rate were determined using a primed-constant infusion of [1(-13) C] leucine. Plasma volume (PV) using Evans Blue dye dilution and total body water (TBW) using bioelectrical impedance analysis were measured on C, R1, and R8. RESULTS: On R1 as compared with C: 1). PV (+23.3 +/- 3.2%; P相似文献   
83.
Constitutive androstane receptor (CAR; NR1I3) controls the metabolism and elimination of endogenous and exogenous toxic compounds by up-regulating a battery of genes. In this work, we analyzed the expression of human CAR (hCAR) in normal liver during development and in hepatocellular carcinoma (HCC) and investigated the effect of hepatocyte nuclear factor 4alpha isoforms (HNF4alpha1 and HNF4alpha7) on the hCAR gene promoter. By performing functional analysis of hCAR 5'-deletions including mutants, chromatin immunoprecipitation in human hepatocytes, electromobility shift and cotransfection assays, we identified a functional and species-conserved HNF4alpha response element (DR1: ccAGGCCTtTGCCCTga) at nucleotide -144. Both HNF4alpha isoforms bind to this element with similar affinity. However, HNF4alpha1 strongly enhanced hCAR promoter activity whereas HNF4alpha7 was a poor activator and acted as a repressor of HNF4alpha1-mediated transactivation of the hCAR promoter. PGC1alpha stimulated both HNF4alpha1-mediated and HNF4alpha7-mediated hCAR transactivation to the same extent, whereas SRC1 exhibited a marked specificity for HNF4alpha1. Transduction of human hepatocytes by HNF4alpha7-expressing lentivirus confirmed this finding. In addition, we observed a positive correlation between CAR and HNF4alpha1 mRNA levels in human liver samples during development, and an inverse correlation between CAR and HNF4alpha7 mRNA levels in HCC. These observations suggest that HNF4alpha1 positively regulates hCAR expression in normal developing and adult livers, whereas HNF4alpha7 represses hCAR gene expression in HCC.  相似文献   
84.
BACKGROUND/AIMS: Combined hepatocellular-cholangiocarcinoma (HCC-CC) show dual hepatocellular and biliary epithelial differentiation. To better understand the relations between cholangiocarcinoma (CC), HCC-CC and hepatocellular carcinoma (HCC), we screened for genetic alterations. METHODS: A series of nine CC, 15 HCC-CC and three separated HCC and CC lesions ('collision tumors') were screened for loss of heterozygosity (LOH) using 400 microsatellite markers and for p53 and beta-catenin mutations. A comparison with a previously characterized series of 137 HCC was performed. RESULTS: In six cases of CC and HCC-CC, we identified TP53 gene mutations. A CTNNB1/beta-catenin was identified in two patients presenting collision tumors, but no mutations were found in CC or in HCC-CC. A high level of chromosome instability in both CC and HCC-CC was found. Recurrent specific LOH were identified at 3p and 14q in more than 50% of the CC and the HCC-CC cases, whereas these chromosomal regions were deleted in less than 10% of the HCC cases (P<10(-5)). Minimal common regions of deletion (MCRD) were defined at 3p24-p14 and 14q24-q32, respectively. CONCLUSIONS: These results suggest that combined HCC-CC are genetically closer to CC than HCC and common carcinogenesis pathways may be altered in HCC-CC and CC.  相似文献   
85.
The Losartan Intervention For Endpoint reduction in hypertension (LIFE) study reported that a losartan-based antihypertensive regimen reduced cardiovascular morbidity and mortality (composite of cardiovascular death, stroke, and myocardial infarction) more than therapy based on atenolol in patients with left ventricular hypertrophy and isolated systolic hypertension (ISH). Patients aged 55-80 years with blood pressures 160-200/<90 mm Hg were followed for a mean of 4.7 years. Blood pressure was similarly reduced in the losartan (n=660) and atenolol (n=666) ISH groups. There were 88 (6.6%) patients who experienced a stroke, 18 of which were fatal. Of patients experiencing strokes, 72.7% had an ischemic stroke. ISH patients in LIFE compared to the non-ISH group had a higher incidence of any stroke and embolic stroke, and similar incidences of fatal, atherosclerotic, and hemorrhagic/other strokes. The incidence of any stroke (40% risk reduction [RR], p=0.02), fatal stroke (70% RR, p=0.035), and atherothrombotic stroke (45% RR, p=0.022) was significantly lower in losartan-treated compared to the atenolol-treated patients. The 36% RR for embolic strokes in the losartan group was not statistically significantly (p=0.33) different from the atenolol group. These data suggest that losartan-based treatment is more effective than an atenolol-based treatment for patients with ISH and a high risk for stroke.  相似文献   
86.
87.
Obesity and the risk for cardiovascular disease   总被引:1,自引:0,他引:1  
Coronary heart disease (CHD) is the leading cause of mortality in the United States. Hypertension, diabetes mellitus, hypercholesterolemia, and smoking have all been directly related to CHD. Obesity is on the rise in the United States and has also been associated with CHD. This review clearly establishes obesity as an independent risk factor for CHD as demonstrated by the Framingham Heart Study, Nurses' Health Study, Buffalo Health Study, and the Cancer Prevention Study II. Morbid obesity was found to correlate with a significant risk of mortality from CHD, especially in young men. Prevention of obesity, and therefore reduction in risk from cardiovascular disease, is paramount in the management of obesity. New approaches to behavioral, medical, and surgical management of obesity are reviewed, including thalidomide, an antiangiogenic agent. A primary and secondary prevention model details a multidisciplinary approach to reducing risk in obesity.  相似文献   
88.
OBJECTIVE: The objective of this study was to test the hypothesis that obesity increases the sensitivity of rats to experimentally induced hypertension. DESIGN AND METHODS: To induce hypertension, unilaterally nephrectomized lean and obese Zucker rats were injected with 25 mg/kg of deoxycorticosterone acetate (DOCA) twice weekly for 5 weeks and given water containing 1% NaCl to drink. Unilaterally nephrectomized control rats were injected with vehicle and drank tap water. Systolic blood pressure (SBP) was measured by the tail cuff method. Renal histology and urinary albumin excretion were used to assess the effects of the experimental treatment on the kidney. RESULTS: Obese rats exhibited a significant rise in SBP at 4 days after the start of DOCA-salt treatment. In contrast, SBP of DOCA-treated lean rats was not significantly elevated from pretreatment measurements until day 22. Moreover, SBP was significantly higher during the plateau phase of blood pressure development in obese DOCA-salt treated rats (196 mmHg) than in correspondingly treated lean rats (150 mmHg). Both obesity and DOCA-salt treatment promoted glomerulosclerosis and mild tubulointerstitial damage in the kidney with DOCA-salt treatment exacerbating the effect of obesity. Urinary albumin excretion was significantly greater in obese control rats compared with lean controls and in DOCA-treated obese rats relative to vehicle-treated obese rats. CONCLUSION: Results of this study indicate that obese Zucker rats are more sensitive to mineralocorticoid-induced hypertension than lean rats. This study provides experimental evidence supporting the epidemiological findings that obesity is a risk factor for the development of hypertension.  相似文献   
89.
(Headache 2011;51:533‐543) Objective.— To evaluate the efficacy and tolerability of telcagepant when co‐administered with ibuprofen or acetaminophen for the acute treatment of migraine. Background.— Telcagepant is an oral calcitonin gene‐related peptide receptor antagonist which is being evaluated for the acute treatment of migraine. Combining telcagepant with analgesics that have a different mechanism of action could produce greater efficacy. Methods.— Randomized, double‐blind, placebo‐controlled study. Patients were randomized to treat a moderate or severe migraine headache with either telcagepant 280 mg + ibuprofen 400 mg (N = 171), telcagepant 280 mg + acetaminophen 1000 mg (N = 171), telcagepant 280 mg (N = 170), or placebo (N = 171). The primary efficacy endpoint was 2‐hour pain freedom. The study had approximately 88% power to detect an additive effect of at least 15 percentage points (telcagepant combination vs telcagepant monotherapy) and 48% power to detect an additive effect of at least 10 percentage points. Safety and tolerability were assessed by adverse events and laboratory tests. Results.— The percentages of patients with 2‐hour pain freedom were greater in each active treatment group compared to placebo (P < .001): telcagepant + ibuprofen = 35.2%, telcagepant + acetaminophen = 38.3%, telcagepant = 31.2%, placebo = 10.9%. No significant differences were seen for either of the combination groups vs telcagepant monotherapy, but both were numerically larger than telcagepant monotherapy. All the active treatments were generally well tolerated. The percentage of patients reporting any adverse event within 48 hours was higher in the active treatment groups than placebo: telcagepant + ibuprofen = 30.3%, telcagepant + acetaminophen = 31.6%, telcagepant = 24.8%, placebo = 18.2%. The most common adverse events reported by ≥4 patients in one or more of the treatment groups that included telcagepant were fatigue, nausea, dizziness, somnolence, dry mouth, and tremor. Conclusions.— The combination of telcagepant 280 mg with either ibuprofen 400 mg or acetaminophen 1000 mg did not show a statistically significant difference from telcagepant alone. Numerically greater treatment effects in the combination treatment groups over the telcagepant 280 mg monotherapy suggest that telcagepant combination treatments may merit further evaluation in studies powered to detect smaller additive benefits. (Clinicaltrials.gov; NCT00758836).  相似文献   
90.
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