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991.
OBJECTIVES: Liver biopsy is a valuable clinical tool, but for the interpretation to be meaningful a certain core size should be obtained. This study examines the changes the liver biopsy core undergoes during processing steps. METHODS: A total of 61 consecutive percutaneous liver biopsies were obtained between November 2004 and April 2005. The needle type utilized was the 16-gauge automatic tru-cut. A measurement was made while each liver biopsy core specimen resided in the cartridge, then a measurement was made with the core placed on the tray, and a final measurement was made after the pathologist received the formalin-fixed specimen. RESULTS: The mean size of the biopsy core in the cartridge measured 15 +/- 2 mm, compared to a mean size on the tray of 19.6 +/- 3.5 mm, and a mean size after fixation of 18.3 mm. All mean sizes were statistically different from one another. The compressive effect of the cartridge was 23%. The shrinkage effect of formalin fixation was 7%. CONCLUSIONS: The liver biopsy core size changes significantly through the processing steps. It is imperative that the operator is aware of these changes so that appropriate decisions are made. As an example, if the operator underestimates the core size when measured in the cartridge, a second pass may be completed when in fact adequate tissue had been obtained on the first pass.  相似文献   
992.
Introduction: Hereditary hemochromatosis (HH) is an autosomal recessive disorder that occurs in approximately 1 in 200–250 individuals. Mutations in the HFE gene lead to excess iron absorption. Excess iron in the form of non-transferrin-bound iron (NTBI) causes injury and is readily uptaken by cardiomyocytes, pancreatic islet cells, and hepatocytes. Symptoms greatly vary among patients and include fatigue, abdominal pain, arthralgias, impotence, decreased libido, diabetes, and heart failure. Untreated hemochromatosis can lead to chronic liver disease, fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Many invasive and noninvasive diagnostic tests are available to aid in diagnosis and treatment. MRI has emerged as the reference standard imaging modality for the detection and quantification of hepatic iron deposition, as ultrasound (US) is unable to detect iron overload and computed tomography (CT) findings are nonspecific and influenced by multiple confounding variables. If caught and treated early, HH disease progression can significantly be altered.

Area covered: The data on Hemochromatosis, iron overload, and MRI were gathered by searching PubMed.

Expert commentary: MRI is a great tool for diagnosis and management of iron overload. It is safe, effective, and a standard protocol should be included in diagnostic algorithms of future treatment guidelines.  相似文献   

993.
中国肝病患者血清铜蓝蛋白水平的研究   总被引:5,自引:1,他引:5  
目的 探讨我国不同肝病患者血清铜蓝蛋白 (CP)水平交叉程度 ,为肝豆状核变性(WD)的诊断和鉴别诊断提供科学的依据。方法 测定 90 5例正常人、WD及其他各种肝病患者血清CP水平 ,采用SPSS12统计软件进行统计分析。结果 WD患者血清CP平均为 (93 9± 98 1)mg/L ,与其他各组相比差异有非常显著性 ,72 7%的患者低于 10 0mg/L ,其中 4 2 9%的患者低于 5 0mg/L ,但是也有 9 1%的患者其血清CP正常 ,其中 3例高于 4 0 0mg/L ,最高达 5 0 1mg/L。 6 8%的非WD患者血清CP低于正常 ,最低为 2 8mg/L。急性肝炎患者血清CP平均为 (398 4± 15 1 3)mg/L ,显著高于其他各组。重型肝炎患者血清CP平均为 (2 96 5± 10 6 5 )mg/L ,显著低于其他各组 ,其中18 8%的患者低于正常。结论 WD患者CP水平显著低于正常人和其他肝病患者 ,但是与其他肝病有一定程度的交叉 ,单凭CP水平不足以确诊或排除WD。  相似文献   
994.
Epidemiological studies in the developing world are frequently biased by the simultaneous presence of several infectious pathogens. In the present study, we examined the usefulness of circulating markers of oxidative stress and liver fibrosis to investigate the distinct forms of chronic liver inflammations associated with schistosomiasis and viral hepatitis, respectively. The study was performed in a Sudanese population exposed to Schistosoma. Circulating hyaluronic acid (HA) was used as a marker of liver fibrosis; the severity of schistosomiasis was determined by ultrasonic examination; viral hepatitis infection was ascertained by circulating anti-hepatitis antibodies. Serum markers were examined also in Sudanese subjects not exposed to Schistosoma infection and in French control subjects. We found a drastic decrease of lycopene levels in the subjects exposed to schistosomiasis in comparison with non-exposed Sudanese and French control subjects. Retinol, alpha-tocopherol and five carotenoids were unchanged. Lycopene depletion was unlikely to be due to variations of nutritional origin, since the lycopene/beta-carotene ratio was five-fold lower in the population at risk of schistosomiasis than in the other groups. We found that high HA serum levels were associated with severe periportal fibrosis but not with viral infection. Conversely, levels of the oxidized lipid malondialdehyde (MDA) were associated with viral infection but not with the severity of schistosomiasis, even though the two infections had additive effects. We concluded that serum markers are valuable tools for investigating the complex effects of co-existing factors of chronic liver inflammation.  相似文献   
995.
AIM: To analyze the clinical presentation of venous diethylene glycol (DEG) poisoning in patients with preexisting severe liver disease and factors that correlate with DEG poisoning. METHODS: Retrospective chart review was performed to analyze the epidemiology, clinical presentation, hepatorenal functions, hemodynamics and pathological characteristics of 64 patients with severe liver disease who received intravenous armillarisin-A, the solvent of which was DEG. Comparative analyses of correlating factors and causes for poisoning were based on the presence or absence of poisoning. RESULTS: Of the 64 patients who received armillarisin-A, 15 were found to have DEG poisoning. Twelve poisoned patients died. After a mean of 5 d, the poisoned patients displayed acute renal failure. Metabolic acidosis occurred in 13 cases. BUN, Cr, and CO2 values were significantly elevated and exacerbation of digestive tract symptoms and/or symptom was noted in 11 cases. Neurological system impairment was observed in 10 cases after 2 wk. Compared to the 49 non-poisoned patients, the poisoned patients exhibited significantly lower RBC and Hb values and higher WBC count. Renal biopsy from the poisoned patients revealed acute tubular necrosis and interstitial nephritis. Significant differences in preexisting severe hepatitis, ascites, renal disease, and diuretic therapy were found between groups. Prior to diethylene glycol injections, the mean values for neutral granular cells, BUN, Cr, calcium and phosphorous ions differed significantly between groups. CONCLUSION: Venous diethylene glycol poisoning is characterized by oliguric acute renal failure, metabolic acidosis, digestive symptoms, nervous system impairment, and a high probability of anemia and WBC proliferation. Mortality is high. Correlative factors include preexisting severe liver disease, renal disease, and infection.  相似文献   
996.
997.
Primary squamous cell carcinoma of the liver is extremely rare, very difficult to diagnose, and carries an extremely poor prognosis. In this study, we discuss the imaging features of a patient with primary hepatic squamous cell carcinoma. The patient was admitted to hospital owing to discomfort in the right upper abdominal quadrant and a loss of appetite. He had no previous risk factors associated with hepatic squamous cell carcinoma and no history of systemic squamous cell carcinoma. We diagnosed primary hepatic squamous cell carcinoma by pathological analysis. Primary hepatic squamous cell carcinoma is rare, and its histological features are controversial, which makes the clinical and imaging diagnosis difficult. Therefore, it is urgent to improve the understanding of this disease in clinical practice to avoid misdiagnosis, and to identify the best treatment. This case provides a basis for the clinical diagnosis of primary hepatic squamous cell carcinoma.  相似文献   
998.
Abstract

Arginases are a family of enzymes that convert l-arginine to l-ornithine and urea. Alterations in expression of the isoform arginase-I are increasingly recognized in lung diseases such as asthma and cystic fibrosis. To define expression of murine arginase-I in formalin-fixed tissues, including lung, an immunohistochemical protocol was validated in murine liver, a tissue that has distinct zonal arginase-I expression, making it a useful control. In the lung, arginase-I immunostaining was observed in airway surface epithelium and this decreased from large to small airways, with a preferential staining of ciliated epithelium versus Clara cells and alveolar epithelia. In submucosal glands, the ducts and serous acini had moderate immunostaining, which was absent in mucous cells. Focal immunostaining was observed in alveolar macrophages, endothelial cells, pulmonary vein cardiomyocytes, pulmonary artery smooth muscle, airway smooth muscle, and neurons of ganglia of the lung. Arginase-I immunostaining was also detected in other tissues including salivary glands, pancreas, liver, skin, and intestine. Differential immunostaining was observed between sexes in submandibular salivary glands; arginase-I was diffusely expressed in the convoluted granular duct cells of females, but was rarely noted in males. Strain specific differences were not detected. In a mouse with an incidental case of lymphoma, neoplastic lymphocytes lacked arginase-I immunostaining, in contrast to immunostaining detected in non-neoplastic lymphocytes of lymphoid tissues. The use of liver tissue to validate arginase-I immunohistochemistry produced consistent expression patterns in mice, and this approach can be useful to enhance consistency of arginase-I immunohistochemical studies.  相似文献   
999.
The perihepatic space is frequently involved in a spectrum of diseases, including intrahepatic lesions extending to the liver capsule and disease conditions involving adjacent organs extending to the perihepatic space or spreading thanks to the communication from intraperitoneal or extraperitoneal sites through the hepatic ligaments. Lesions resulting from the dissemination of peritoneal processes may also affect the perihepatic space. Here we discuss how to assess the perihepatic origin of a lesion and describe the magnetic resonance imaging (MRI) features of normal structures and fluids that may be abnormally located in the perihepatic space. We then review and illustrate the MRI findings present in cases of perihepatic infectious, tumor-related, and miscellaneous conditions. Finally, we highlight the value of MRI over computed tomography.  相似文献   
1000.
The novel coronavirus, SARS-CoV-2, has caused a global pandemic with high morbidity and mortality. It was first observed to cause a severe acute respiratory syndrome. However, gastrointestinal and hepatic manifestations have been increasingly recognized.Gastrointestinal symptoms include diarrhea, epigastric pain, nausea, and vomiting. Diarrhea is the most common GI manifestation of SARS-CoV-2 and can present without or without respiratory symptoms. Patients with GI symptoms have been associated with longer duration of illness and may be associated with more severe illness. Mechanism of diarrhea is thought to be related to direct viral cytotoxicity occurring when the SARS-CoV-3 enters GI cells via the ACE-2 receptor. Inflammatory response and cytokine release likely contributes to symptoms.SARS-CoV-2 can cause hepatic injury. Studies have shown mild to moderate elevation of liver enzymes. The pattern of liver abnormalities can be hepatocellular, cholestatic or mixed. Patients with severe infection have significantly higher rates of liver injury and worse outcomes. Proposed mechanisms for injury include immune mediated systemic inflammatory response, direct cytotoxicity from viral replication and hypoxia-reperfusion dysfunction.Recent data suggests that GI and hepatic injury may be under-recognized manifestation of SARS-CoV-2 infection. Patients with diarrhea and liver disease may have a worse prognosis. The rapidly evolving literature continues to reveal a growing body of information which enables updated guidance for management. More investigation is needed which focuses on vulnerable patients, including the elderly, those with underlying illness, as well as, racial and ethnic minorities.  相似文献   
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