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621.
622.
Diagnosis of hepatocellular carcinoma   总被引:1,自引:0,他引:1  
Hepatocellular carcinoma (HCC) is one of the commonest cancers worldwide, particularly in parts of the developing world, and is increasing in incidence. This article reviews the current modalities employed for the diagnosis of HCC, including serum markers, radiological techniques and histological evaluation, and summarises international guidelines for the diagnostic approach to HCC.  相似文献   
623.
624.
影响拉米夫定相关乙肝病毒YMDD变异的因素   总被引:8,自引:0,他引:8  
  相似文献   
625.
Osteoporosis is characterized by bone loss. The present study aims to investigate the effects of bovine colostrum (BC) on bone metabolism using ovariectomized (OVX) and orchidectomized (ORX) rat models. Twenty-seven-week-old Wistar Han rats were randomly assigned as: (1) placebo control, (2) BC supplementation dose 1 (BC1: 0.5 g/day/OVX, 1 g/day/ORX), (3) BC supplementation dose 2 (BC2: 1 g/day/OVX, 1.5 g/day/ORX) and (4) BC supplementation dose 3 (BC3: 1.5 g/day/OVX, 2 g/day/ORX). Bone microarchitecture, strength, gene expression of VEGFA, FGF2, RANKL, RANK and OPG, and bone resorption/formation markers were assessed after four months of BC supplementation. Compared to the placebo, OVX rats in the BC1 group exhibited significantly higher cortical bone mineral content and trabecular bone mineral content (p < 0.01), while OVX rats in the BC3 group showed significantly higher trabecular bone mineral content (p < 0.05). ORX rats receiving BC dose 2 demonstrated significantly higher levels of trabecular bone mineral content (p < 0.05). Serum osteocalcin in the ORX was pointedly higher in all BC supplementation groups than the placebo (BC1: p < 0.05; BC2, BC3: p < 0.001). Higher doses of BC induced significantly higher relative mRNA expression of OPG, VEGFA, FGF2 and RANKL (p < 0.05). BC supplementation improves bone metabolism of OVX and ORX rats, which might be associated with the activation of the VEGFA, FGF2 and RANKL/RANK/OPG pathways.  相似文献   
626.
Dendritic cells (DCs) initiate adaptive immune responses by activating T cells via cognate interactions between MHC-peptide complexes and T cell receptors. In immature DCs, MHC class II is predominantly stored in late endocytic compartments, where it has a short half-life because of degradation. In contrast, mature DCs recruit MHC class II to the plasma membrane. We here demonstrate that in immature DCs, the beta-chain of MHC class II was oligoubiquitinated after proteolytic processing of the associated invariant chain in endosomes and that this modification was required for efficient endocytosis and sorting into luminal vesicles of multivesicular bodies. Ubiquitination of MHC class II was suppressed in lipopolysaccharide-activated DCs. Mutated MHC class II lacking its ubiquitination site was expressed at the plasma membrane, irrespective of DC maturation. Together, these data provide a molecular basis for the regulation of MHC class II-mediated antigen presentation by DCs.  相似文献   
627.
Palmoplantar psoriasis and palmoplantar pustulosis are chronic skin diseases with a large impact on patient quality of life. They are frequently refractory to treatment, being generally described as a therapeutic challenge. This article aims to review the definitions of palmoplantar psoriasis and palmoplantar pustulosis, highlighting the similarities and differences in terms of epidemiology, clinical presentation, genetics, histopathology, and pathogenesis, as well as treatment options for both entities. Classical management of mild to moderate palmoplantar pustulosis and palmoplantar psoriasis relies on use of potent topical corticosteroids, phototherapy, and/or acitretin. Nevertheless, these drugs have proven to be insufficient in long-term control of extensive disease. Biologic therapy—namely, anti-interleukin-17 agents and phosphodiesterase type 4 inhibitors—has recently shown promising results in the treatment of palmoplantar psoriasis. Knowledge of the pathophysiologic pathways of both entities is of utmost importance and may, in the future, allow development of molecularly targeted therapeutics.  相似文献   
628.
From February 2004 to April 2006, the concentrations of more than 10 metals in mussels (Mytilus galloprovincialis) were measured in 10 stations from Galicia to the Basque Country in 8 different times of sampling. The mean highest concentrations are found for Zn [226.8 μg/g, dry weight (d.w.)] followed by Mn, As, Cu, and Co (between 10 and 25 μg/g d.w.). Lower mean concentrations are found for Se, Cr, Pb, V, and Ni (between 2 and 8 μg/g d.w.) and the lowest are for Cd, Sn, Hg, and Sb (between 0.05 and 1 μg/g d.w.). Among the statistical treatments used, the factor analysis showed a clustering of the mussels according to the geographical location. In addition, the temporal trend of the metal concentrations was studied by means of the Mann–Kendall test. In this sense, some stations showed a decreasing trend in the accumulation of the metallic content. However, there were some local pollution events that could be explained as a consequence of anthropogenic activities. Finally, the effects of the oil spill from the Prestige are discussed based on the experimental Ni/V ratio values obtained from this work and those of the original oil.  相似文献   
629.
Dermatofibrosarcoma Protuberans (DFSP) is a rare malignant soft‐tissue neoplasm which is often misdiagnosed due to its indolent clinical course and non‐specific radiological appearances. An observation case series was conducted with retrospective review of clinical and radiological data of DFSP patients presenting to a major tertiary hospital in Hong Kong for radiological assessment between November 2006 and February 2016. Seven patients with confirmed histological diagnosis of DFSP were included. Tumour sizes at presentation ranged from 1 to 5 cm, most commonly (n = 6) occurred over chest wall and abdominal wall. History of previous local trauma or surgery was identified in the majority of cases (n = 4). There was poor correlation between pre‐imaging clinical diagnoses and pathological diagnoses. Local recurrence and tumour de‐differentiation with sarcomatous changes occurred in the minority of cases (n = 2). A common radiological ‘claw’ sign at the lesion/skin interface formed by elongated appendages of the tumour superficially was appreciated in most cases (n = 6). A history of previous local trauma or surgery serves as a possible etiological factor for the development of DFSP. High clinical suspicion for the entity is essential in its detection and differentiation from simple wound complications and local recurrence of other benign lesions. The radiological ‘claw’ sign at the lesion/skin interface might serve as a tell‐tale sign for cutaneous tumour involvement. A comprehensive analysis of imaging findings in conjunction with individual clinical presentations is the key to accurate diagnoses and proper management.  相似文献   
630.
In Manaus, Amazonas State, Brazil, the degree of individual exposure to leishmaniasis is related to disorganized land occupation. In order to evaluate predisposing factors for an outbreak, confirm the parasitological diagnosis, treat patients, and assess etiological agents, reservoirs, and vectors, a 12-month study was conducted in Manaus in a community located along the BR-174 federal highway. Some 451 individuals were studied, among whom 17 cases of American tegumentary leishmaniasis (ATL) were diagnosed (six women and 11 men). Age varied from one to 64 years. Eleven patients had from one to three lesions. As for reservoirs, three opossums were captured. No hemoflagellates were found in the blood tests. Lutzomyia umbratilis was the predominant vector species captured. Many ATL patients were engaged in activities that exposed them to Leishmania vectors. Some patients may have been infected in the household and peridomiciliary environments. The epidemiological profile of ATL in this community is similar that of other foci in the region. This case series characterizes ATL as an endemic local public health problem.  相似文献   
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