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71.
环氧司坦(2-氰基-3,17 α-二羟基-4β,17β-二甲基-4α,5α-环氧-雄甾烯(epostane)被认为是颇有希望的止孕药物,国外已应用于临床,为了进一步探讨环氧司坦的止孕机理,我们研究了它对离体人胎盘滋养层细胞和豚鼠黄体细胞的直接作用及对hCG的促黄体激素生成作用和小鼠胚胎与子宫内膜“共培养”的影响。  相似文献   
72.
Elevated serum ferritin levels, especially of the H subunit, accompany many clinical malignancies. By using the subtraction-enhanced display technique, we have recently isolated several cDNA clones which are over- expressed in rat hepatocellular carcinoma induced by diethylnitrosamine. One 830-base-pair clone was 88% similar to human ferritin-H cDNA and encoded a 182 amino acid protein which is 97% homologous to human ferritin-H chain. Hepatic mRNA levels of ferritin-H were increased markedly at the early stage of diethylnitrosamine- induced hepatocarcinogenesis in the rat (6 weeks) and appeared more than 10-fold overexpressed as the tumour progressed. In contrast, hepatic ferritin-H mRNA remained constant during liver regeneration after a 70% partial hepatectomy. In situ hybridization showed that over- expression of ferritin-H was exclusively localized to preneoplastic foci, to tumour nodules and to tumour cells invading blood vessels. These findings suggest that ferritin-H is a highly conserved protein, its over-expression during tumour development is phenotypically correlated with tumour initiation and/or progression, and it is useful as an early marker for hepatocellular carcinoma.   相似文献   
73.
Diagnostic imaging plays a key role in the diagnosis and management of inflammatory bowel disease(IBD). However due to the relapsing nature of IBD, there is growing concern that IBD patients may be exposed to potentially harmful cumulative levels of ionising radiation in their lifetime, increasing malignant potential in a population already at risk. In this review we explore the proportion of IBD patients exposed to high cumulative radiation doses, the risk factors associated with higher radiation exposures, and we compare conventional diagnostic imaging with newer radiation-free imaging techniques used in the evaluation of patients with IBD. While computed tomography(CT) performs well as an imaging modality for IBD, the effective radiation dose is considerably higher than other abdominal imaging modalities. It is increasingly recognised that CT imaging remains responsible for the majority of diagnostic medical radiation to which IBD patients are exposed. Magnetic resonance imaging(MRI) and small intestine contrast enhanced ultrasonography(SICUS) have now emerged as suitable radiation-free alternatives to CT imaging, with comparable diagnostic accuracy. The routine use of MRI and SICUS for the clinical evaluation of patients with known or suspected small bowel Crohn’s disease is to be encouraged wherever possible. More provision is needed for out-of-hours radiation-free imaging modalities to reduce the need for CT.  相似文献   
74.
Septic arthritis commonly occurs in the rheumatoid arthritis population. The diagnosis is frequently delayed and the associated mortality is high. In this brief report, we present a patient with rheumatoid arthritis and prosthetic knee joints who developed septic arthritis and had persisting evidence of Staphylococcus aureus DNA in synovial fluid, from his knees, which was detected by polymerase chain reaction (PCR) and a gene probe. This was detected until 10 weeks of therapy despite adequate antibiotic treatment and a sterile synovial fluid. In the future, it may be found that PCR of the synovial fluid will be a valuable investigation for the diagnosis and management of septic arthritis.   相似文献   
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76.
Wegener's granulomatosis (WG) is an inflammatory disorder characterized by granulomatous inflammation and vasculitis, and is strongly associated with antineutrophil cytoplasmic antibodies (ANCA). ANCA in patients with WG are directed against proteinase 3 (Pr3) in most of the cases. In vitro, upon neutrophil priming, ANCA antigens are expressed on the cell surface, thereby becoming available for interaction with ANCA. Subsequently, these neutrophils become activated. Since ANCA can only interact with leucocytes when the ANCA antigens are present on the cell surface, we questioned whether Pr3 is already expressed on the membranes of circulating granulocytes and monocytes of patients with WG, and whether Pr3 expression is related to disease activity, so explaining the systemic nature and severity of the disease. The expression of Pr3, and other ANCA antigens, i.e. myeloperoxidase (MPO) and human leucocyte elastase (HLE), was analysed on circulating granulocytes and monocytes by flow cytometry, using a non-activating whole-blood method. Disease activity was quantitated using the Birmingham Vasculitis Activity Score (BVAS). Seventeen patients with active WG and anti-Pr3 antibodies were included in this study. Nine of these patients were also analysed at the time of remission. Twelve patients with sepsis served as positive controls, and 10 healthy volunteers as negative controls for granulocyte/monocyte activation. Pr3 expression on neutrophils was increased in patients with active WG compared to patients with quiescent disease and healthy controls. On monocytes, no differences in Pr3 expression were found between those groups. Furthermore, the expression of MPO and HLE did not differ between patient groups and healthy controls. Upon follow-up, the expression of Pr3 on neutrophils from patients with active WG decreased when patients went into remission. Pr3 expression on neutrophils correlated with the BVAS score (r = 0.40, P < 0.05). In conclusion, circulating neutrophils from patients with active WG have increased expression of Pr3. In addition, the expression of Pr3 correlates with disease activity, suggesting that the availability of Pr3 for interaction with ANCA plays a central role in the disease process.   相似文献   
77.
78.
SUMMARY Described is a confirmed case of non-convulsive status epilepticus, an unusual presentation of M. pneumoniae infection. The postulated pathological mechanisms in this infection are reviewed.  相似文献   
79.
Infections and Wegener's granulomatosis--a cause and effect relationship?   总被引:1,自引:0,他引:1  
The association of infections and autoimmune disease has been noted by various authors. Several mechanisms have been proposed to explain this, with no current consensus. Wegener's granulomatosis (WG) is an autoimmune disease involving predominantly the pulmonary and renal systems, and is associated with a distinct autoantibody-the anti neutrophil cytoplasmic antibody (ANCA). Although no solid evidence implicates infections in the emergence of WG, direct and circumstantial data suggest this relation. We review this evidence and discuss possible underlying mechanisms. We emphasize the relationship between infections and ANCA, and their role in the maintenance of the 'on- going' inflammatory response.   相似文献   
80.
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