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71.
Hepatic arterial pseudoaneurysm is a rare but potentially fatal condition that requires prompt management. We report a case of hepatic arterial pseudoaneurysm developed after radiofrequency ablation of a hepatocellular carcinoma. The patient was successfully treated with percutaneous absolute ethanol injection under ultrasound guidance. Follow-up studies with ultrasound and computed tomography for 2 years after treatment revealed no evidence of local recurrence of hepatocellular carcinoma and of the pseudoaneurysm.  相似文献   
72.
A heat-labile Epstein-Barr virus-specific DNA polymerase stimulatory protein having a molecular mass of 45 kDa was purified from phorbol 12-myristate 13-acetate-treated P3HR-1 cells by column chromatography. The virus DNA polymerase stimulatory protein was precipitated by sera from patients with nasopharyngeal carcinoma but not by sera from healthy donors. The interaction of the stimulatory protein with DNA polymerase was stoichiometric. Furthermore, this protein stimulated Epstein-Barr virus DNA polymerase but not herpes simplex virus type 1 or type 2 or human DNA polymerase alpha. The stimulatory protein did not alter the Km value of dTTP or DNA but did increase the Vmax of DNA polymerase. Salt concentrations between 100 mM and 150 mM KCl were optimal for this protein-induced stimulation of Epstein-Barr virus DNA polymerase activity. The presence of the stimulatory protein in the reaction mixture enhanced the sensitivity of virus DNA polymerase to phosphonoformate.  相似文献   
73.
74.
Herpes simplex virus (HSV) encodes a DNA polymerase that is similar in several respects to the replicative mammalian DNA polymerase alpha. Recently, these and other DNA polymerases have been shown to share several regions of protein sequence similarity. Despite these similarities, antiviral drugs that mimic natural polymerase substrates specifically inhibit herpesvirus DNA polymerases. To study amino acids involved in substrate and drug recognition, we have characterized and mapped altered drug sensitivity markers of nine HSV pol mutants and sequenced the relevant portions of these mutants. The mutations were found to occur within four relatively small regions. One such region, which we designate region A, has sequence similarity only to DNA polymerases that are sensitive to certain antiviral drugs. The other three regions contain sequences that are similar among various DNA polymerases. The multiple mutations occurring within two of these regions make it likely that the regions interact directly with drugs and substrates. Our results lead us to favor a model in which protein folding allows interactions among the four regions to form the substrate and drug binding sites.  相似文献   
75.
Lee PT  Fang HC  Chen CL  Chiou YH  Chou KJ  Chung HM 《Lupus》2003,12(11):827-832
We studied the clinical course of 26 systemic lupus erythematosus (SLE) patients who started regular dialysis at our hospital and whose stay exceeded a three-month duration in order to investigate the long-term prognosis in a Chinese cohort. Clinical and serological activities of lupus before and after dialysis were analysed. To compare the long-term survival rate, controls were set using 78 age-matched end-stage renal disease (ESRD) patients who did not have SLE or diabetes mellitus and entered the chronic dialysis program at a similar period with SLE dialysis patients. There was a significant decrease in clinical lupus activity after starting regular dialysis (P < 0.05); however, the serological activity remained the same. The five-and ten-year survival rates were significantly lower in the SLE patients (73 and 38% in the SLE group versus 95 and 88% in the non-SLE group, P < 0.05). SLE patients had a 4.3-times higher risk of death than non-SLE patients (P < 0.05, 95% confidence interval, 1.2-15.2). Also, the deceased SLE patients had persistent lower serum levels of complement 3. SLE patients with ESRD remain clinically quiescent despite persistent serological abnormalities and have a worse prognosis than other uremia patients in the Chinese population.  相似文献   
76.
Pistacia lentiscus var. Chia (Anacardiaceae) grows almost exclusively on Chios Island, Greece, and gives a resinous exudate resin used for culinary purposes by Mediterranean people. We investigated the molecular mechanisms through which total polar extract of the resin inhibits oxidized low-density lipoprotein (oxLDL) cytotoxic effect on peripheral blood mononuclear cell (PBMC). Cells exposed to oxLDL underwent apoptosis and necrosis, dependent on the duration of exposure. When culturing cells with oxLDL and the polar extract concurrently, we observed inhibition of both the phenomena. Because under oxidative stress the pro-oxidant systems outbalance the antioxidant, potentially producing oxidative damage and ultimately leading to cell death, we measured the levels of intracellular antioxidant glutathione (GSH). Additionally, we measured CD36 expression, a class B scavenger receptor, on CD14-positive cells, as CD36 has been identified as the oxLDL receptor in macrophages and may play a pivotal role in atherosclerotic foam cell formation. oxLDL decreased GSH levels and upregulated CD36 expression. P. lentiscus extract restored GSH levels and downregulated CD36 expression, even at the mRNA level. In order to find out the biologically drastic constituents of the resin's polar extract, fractions derived from RP-HPLC analysis were examined for their antioxidant effect on oxidatively stressed PBMC. The triterpenoid fraction revealed remarkable increase in intracellular GSH. We suggest GSH restoration and downregulation of CD36 mRNA expression as the pathways via which P. lentiscus triterpenes exert antioxidant/antiatherogenic effect. Additionally, our results provide strong evidence of the resin's antiatherogenic effect; therefore it is credited with beneficial health aspects.  相似文献   
77.
ABSTRACT

Mobile health (M-Health) has become a novel method for HIV prevention and the effects need to be promoted. The study purpose was to exam how a smartphone application (app) reduces HIV risky behaviour in men who have sex with men (MSM). The Safe Behaviour and Screening (SBS) app was developed, and included five features: record, output, and resources connection; information provision; testing services; interaction; and online statistics. A random assignment was used. The experimental group used the SBS app for six months. The control group did not use any intervention. There were 130 participants in the experimental group, and 135 in the control group. The average age of all subjects was 27.38 (SD?=?5.56). Compared to the control group, the experimental group had significantly higher mean score of safe behaviour knowledge, motivation, and skills; percentage of condom use during anal intercourse; frequency of searching for testing resources and getting HIV and syphilis tests. The frequency of anal intercourse and recreational drug usage were significantly lower in the experimental group. The SBS app could decrease the HIV risky behaviour among MSM and be applied to HIV prevention and nursing intervention.  相似文献   
78.
BACKGROUND: Accurate, non-invasive characterization of culprit lesions in patients after acute myocardial infarction (AMI) remains challenging. In this prospective study, multidetector row computed tomography (MDCT) is used to assess culprit and active complex lesions in patients early after AMI. METHODS AND RESULTS: We enrolled 103 patients with first non ST-elevation AMI who underwent 64-slices MDCT and conventional coronary angiography (CCAG). The definition of culprit lesion, stable non-culprit lesions and non-culprit active complex lesions was based on the findings of CCAG. The lesions were analyzed with MDCT data. In culprit lesions (n=103), luminal artery stenosis, remodeling index, plaque area and burden were significantly higher than non-culprit lesions (n=129). Multivariate discriminant analysis showed that MDCT density could discriminate culprit from non-culprit lesions. Receiver-operator characteristic curve analysis identified the optimal cutoff value of lesion density for discrimination between culprit and non-culprit lesion as 49.6 Hounsfield units (HU); this value was associated with a sensitivity, specificity and accuracy of 88.4%, 87.4%, and 87.9%, respectively. The MDCT in the stable non-culprit lesions (81.8+/-15.5 HU) was significantly higher than that in culprit lesions or non-culprit active complex lesions (33.2+/-13.8 and 48.3+/-15.7 HU, p<0.001). CONCLUSIONS: MDCT can predict culprit lesions in patients early after AMI, and identify multiple complex lesions.  相似文献   
79.

Aims

To assess whether the increased knowledge and resources available to physicians led to differences in dialysis and survival rates between physicians and non-physician patients with diabetes.

Methods

All newly diagnosed (1997–2009) type 2 diabetes patients aged ≥35 years from the National Health Insurance Program of Taiwan database were included. After propensity score matching (1:10), we estimated the relative risk of dialysis and death using Cox proportional hazards model adjusted for demographic characteristics and comorbidities.

Results

Physicians with diabetes were more likely to start dialysis than general patients, with a 48% increased hazard risk (HR) (P = 0.006). Physicians with diabetes had significantly lower risk of death (HR: 0.88; P = 0.025). However, those requiring dialysis had a non-significant increased risk of death (HR: 1.19). There was an increased HR for death in older physicians (HR: 1.81; P < 0.001) and those with cancer or catastrophic illness. The HR of dialysis (7.89; P < 0.0001) increased dramatically with increasing Charlson Comorbidity Index scores.

Conclusions

Physicians with DM survived longer than other patients with diabetes, likely benefiting from their professional resources in disease control and prevention. Nonetheless, they displayed no advantage from their medical backgrounds compared with the general patients if they developed end stage renal disease.  相似文献   
80.
The association between rheumatoid arthritis (RA) and cancer is still controversial. This study aimed to estimate cancer incidence (both overall and site-specific) among patients with RA and to determine whether their cancer risk was higher than in the general population. We used the nationwide dynamic cohort from the National Health Insurance Research Database of Taiwan and obtained a total of 30,504 patients with no history of cancer who were newly diagnosed with RA between 1996 and 2008; they were followed up until 2010. Standardized incidence ratios (SIR) by age for various types of cancer were calculated in 5-year calendar periods by 5-year age intervals (quinquinquennium) to compare elevated risk of increasing age and increased cancer rate in later calendar years in Taiwan. During 225,432 person-years of follow-up, 1,595 cancers occurred, corresponding to 7.08 per 1,000 person-years. The SIR for all cancers was 0.93 (95 % CI 0.88–0.97). Most cancers were found in the first 2 years after diagnosis of RA, but the incidence decreased afterward. A significant excess of Hodgkin’s lymphoma (SIR 3.31, 95 % CI 1.24–8.81) and non-Hodgkin’s lymphoma (SIR 3.18, 95 % CI 2.64–3.83) was seen among patients with RA, whereas the risk of colorectal cancer was 29 % lower than the general population. In conclusion, this study showed that patients with RA do not have increased overall risk of cancers but have higher risk of hematologic malignancies and lower risk of colorectal cancer, than the general population.  相似文献   
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