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81.
A biloma is an encapsulated bile collection outside the biliary tree. Most cases of biloma are caused by iatrogenic injury or trauma. Intrahepatic rupture of the biliary tree due to nontraumatic cause is a rare event. A 68- year-old man was admitted because of abdominal pain and fever. He had no past history of abdominal surgery, instrumentation or trauma. Computed tomography (CT) scan and magnetic resonance cholangiopancreatography (MRCP) demonstrated a large subcapsular fluid collection in the right liver associated with choledocholithiasis and cholecystitis. Biloma was confirmed by sono-guided percutaneous needle aspiration and was drained through a pigtail catheter. After the successful treatment by percutaneous drainage and endoscopic sphincterotomy, the patient recovered. Here, we report an uncommon case of spontaneous biloma formation in association with choledocholithiasis with a review of literatures.  相似文献   
82.
Stroke Risk Stratification . Introduction: Appropriate stroke risk stratification is essential to ensure suitable tailoring of antithrombotic therapy. The objective of this study was to assess the predictive value of stroke risk classification schemes and to identify patients with atrial fibrillation (AF) who are at substantial risk of stroke despite optimal anticoagulant therapy, in a “real world” consecutive elderly AF cohort. Methods: Six hundred and sixty‐two consecutive AF patients (mean [SD] age 74 [7.7] years; 36.1% female) referred to the Anticoagulation Clinic of the Azienda Ospedaliera Careggi of Florence, Italy, were included and followed‐up for a mean 3.6 ± 2.7 years for the incidence of thromboembolic (TE) events. The ability of the new CHA2DS2‐VASc schema to predict TE was compared with other contemporary stroke risk schema (including CHADS2, NICE 2006, ACC/AHA/ESC 2006, and ACCP 2008), by determining the c‐statistic. Results: Univariate predictors of TE events were female gender (odds ratio 1.9; 95%CI [confidence intervals] 1.01–3.70) and previous stroke/transient ischemic attack (TIA)/TE (OR 5.6; 95%CI 2.70–11.45), although after adjustment only previous stroke/TIA/TE was an independent predictor of TE (OR 5.5; 95%CI 2.68–11.31; P = 0.0001). All stroke risk schema had modest discriminating ability, with c‐statistics ranging from 0.54 (atrial fibrillation investigators [AFI]) to 0.72 (CHA2DS2‐VASc). The CHADS2 and CHA2DS2‐VASc schemes having the best c‐statistics (0.717 and 0.724, respectively) with significant discriminating value between risk strata (both P < 0.001). The proportion of patients assigned to individual risk categories varied widely across the schema, with those categorized as “moderate‐risk” ranging from 5.3% (CHA2DS2‐VASc) to 49.2% (CHADS2‐classical). Conclusion: In this “real world” cohort, current published risk schemas have modest predictive ability, with the CHADS2 and CHA2DS2‐VASc schemes having the best predictive value for thromboembolism. Future trials could assess the value of alternative strategies for thromboprophylaxis in high‐risk anticoagulated patients identified by these schemes. (J Cardiovasc Electrophysiol, Vol. 22, pp. 25‐30, January 2011)  相似文献   
83.
Most current approaches to multiantigen fluorescent imaging require overlaying of multiple images taken with separate filter sets as a result of differing dye excitation requirements. This requirement for false-color composite imaging prevents the user from visualizing multiple species in real time and disallows imaging of rapidly moving specimens. To address this limitation, here we investigate the use of oligodeoxyfluoroside (ODF) fluorophores as labels for antibodies. ODFs are short DNA-like oligomers with fluorophores replacing the DNA bases and can be assembled in many colors with excitation at a single wavelength. A DNA synthesizer was used to construct several short ODFs carrying a terminal alkyne group and having emission maxima of 410–670 nm. We developed a new approach to antibody conjugation, using Huisgen–Sharpless cycloaddition, which was used to react the alkynes on ODFs with azide groups added to secondary antibodies. Multiple ODF-tagged secondary antibodies were then used to mark primary antibodies. The set of antibodies was tested for spectral characteristics in labeling tubulin in HeLa cells and revealed a wide spectrum of colors, ranging from violet-blue to red with excitation through a single filter (340–380 nm). Selected sets of the differently labeled secondary antibodies were then used to simultaneously mark four antigens in fixed cells, using a single image and filter set. We also imaged different surface tumor markers on two live cell lines. Experiments showed that all colors could be visualized simultaneously by eye under the microscope, yielding multicolor images of multiple cellular antigens in real time.  相似文献   
84.
OBJECTIVES: To develop an automated imaging assessment tool that accommodates the anatomic variability of the elderly and demented population as well as the registration errors occurring during spatial normalization. METHODS: 20 subjects with Alzheimer's disease (AD), mild cognitive impairment, or normal cognition underwent MRI brain imaging and had their 3D volumetric datasets manually partitioned into 68 regions of interest (ROI) termed sub-volumes. Gray matter (GM), white matter (WM), and cerebral spinal fluid (CSF) voxel counts were then made in the subject's native space for comparison against automated volumetric measures within three sub-volume probabilistic atlas (SVPA) models. The three SVPAs were constructed using 12 parameter affine (12 p), 2nd order (2nd), and 6th order (6th) transforms derived from registering the manually partitioned scans into a Talairach compatible AD population-based target. The three SVPA automated measures were compared to the manually derived measures in the 20 subjects' native space with a "jack-knife" procedure in which each subject was assessed by an SVPA they did not contribute toward constructing. RESULTS: The mean left and right GM ratio (GM ratio = [GM + CSF] / CSF) "r values" for the 3 SVPAs compared to the manually derived ratios across the 68 ROIs were 0.85 for the 12p SVPA, 0.88 for the 2nd SVPA, and 0.89 for the 6th SVPA. The mean left and right WM ratio (WM ratio = [WM + CSF] / CSF) "r values" for the 3 SVPAs being 0.84 for the 12p SVPA, 0.86 for the 2nd SVPA, and 0.88 for the 6th SVPA. CONCLUSION: We have constructed, from an elderly and demented cohort, an automated brain volumetric tool that has excellent accuracy compared to a manual gold standard and is capable of regional hypothesis testing and individual patient assessment compared to a population.  相似文献   
85.
86.
High residual platelet activation (HRPA) after ADP stimuli has associated with recurrent vascular events in acute atherothrombosis with the use of antiplatelet agents (APAs). However, there has been little evidence supporting this association in acute ischemic stroke (AIS). In this study, we evaluated the influences of HRPR after ADP stimuli on the 1-year incidence of recurrent cardiovascular events and mortality in AIS with APAs. We conducted an observational, referral center cohort study on 968 AIS patients with APAs from January 2010 to December 2013 who were evaluated using optical platelet aggregometry (OPA). All patients received the dual APA combination of aspirin and clopidogrel or aspirin alone. We evaluated their platelet function 5 days after hospital admission using OPA. HRPR after ADP stimuli was defined as platelet aggregation of 70 % or greater according to OPA after 10 µM ADP stimuli. The primary endpoint was a composite of all causes of death, myocardial infarction, and stroke at the 1-year follow-up. The secondary endpoints were each component of the primary endpoint. The event rate of primary endpoint was 11.3 % (109/968). Its rate was significantly higher in the patients with HRPR (16.7 %) than in those without (9.7 %). HPRP was independently associated with the primary endpoint (OR = 1.97, CI 1.22–3.18, p < 0.01). According to the AIS subtype, the presence of HRPR was independently significant for the occurrence of the primary endpoint in the large artery atherosclerosis (LAA) subtype only (OR = 2.26, CI 1.15–4.45, p = 0.02). In this study, the presence of HRPR after ADP stimuli is associated with a poor long-term outcome after acute ischemic stroke. In particular, the influence of this factor might be more prominent in LAA compared with other types of AIS.  相似文献   
87.

Background

Understanding the relationship between alcohol abuse, a common and theoretically modifiable condition, and the most common cause of death in the world, cardiovascular disease, may inform potential prevention strategies.

Objectives

The study sought to investigate the associations among alcohol abuse and atrial fibrillation (AF), myocardial infarction (MI), and congestive heart failure (CHF).

Methods

Using the Healthcare Cost and Utilization Project database, we performed a longitudinal analysis of California residents ≥21 years of age who received ambulatory surgery, emergency, or inpatient medical care in California between 2005 and 2009. We determined the risk of an alcohol abuse diagnosis on incident AF, MI, and CHF. Patient characteristics modifying the associations and population-attributable risks were determined.

Results

Among 14,727,591 patients, 268,084 (1.8%) had alcohol abuse. After multivariable adjustment, alcohol abuse was associated with an increased risk of incident AF (hazard ratio [HR]: 2.14; 95% confidence interval [CI]: 2.08 to 2.19; p < 0.0001), MI (HR: 1.45; 95% CI: 1.40 to 1.51; p < 0.0001), and CHF (HR: 2.34; 95% CI: 2.29 to 2.39; p < 0.0001). In interaction analyses, individuals without conventional risk factors for cardiovascular disease exhibited a disproportionately enhanced risk of each outcome. The population-attributable risk of alcohol abuse on each outcome was of similar magnitude to other well-recognized modifiable risk factors.

Conclusions

Alcohol abuse increased the risk of AF, MI, and CHF to a similar degree as other well-established risk factors. Those without traditional cardiovascular risk factors are disproportionately prone to these cardiac diseases in the setting of alcohol abuse. Thus, efforts to mitigate alcohol abuse might result in meaningful reductions of cardiovascular disease.  相似文献   
88.
Phosphorylation of factor Va and factor VIIIa by activated platelets   总被引:3,自引:3,他引:3  
Kalafatis  M; Rand  MD; Jenny  RJ; Ehrlich  YH; Mann  KG 《Blood》1993,81(3):704-719
Platelet activation leads to the incorporation of 32[PO4(2-)] into bovine coagulation factor Va and recombinant human factor VIII. In the presence of the soluble fraction from thrombin-activated platelets and (gamma-32P) adenosine triphosphate, radioactivity is incorporated exclusively into the M(r) = 94,000 heavy chain (H94) of factor Va and into the M(r) = 210,000 to 90,000 heavy chains as well into the M(r) = 80,000 light chain of factor VIII. Proteolysis of the purified phosphorylated M(r) = 94,000 factor Va heavy chain by activated protein C (APC) gave products of M(r) = 70,000, 24,000, and 20,000. Only the intermediate M(r) = 24,000 fragment contained radioactivity. Because the difference between the M(r) = 24,000 and M(r) = 20,000 fragments is located on the COOH-terminal end of the bovine heavy chain, phosphorylation of H94 must occur within the M(r) = 4,000 peptide derived from the carboxyl-terminal end of H94 (residues 663 through 713). Exposure of the radioactive factor VIII molecule to thrombin ultimately resulted in a nonradioactive light chain and an M(r) = 24,000 radioactive fragment that corresponds to the carboxyl-terminal segment of the A1 domain of factor VIII. Based on the known sequence of human factor VIII, phosphorylation of factor VIII by the platelet kinase probably occurs within the acidic regions 337 through 372 and 1649 through 1689 of the procofactor. These acidic regions are highly homologous to sequences known to be phosphorylated by casein kinase II. Results obtained using purified casein kinase II gave a maximum observed stoichiometry of 0.6 mol of 32[PO4(2-)]/mol of factor Va heavy chain and 0.35 mol of 32[PO4(2-)]/mol of factor VIII. Phosphoamino acid analysis of phosphorylated factor Va by casein kinase II or by the platelet kinase showed only the presence of phosphoserine while phosphoamino acid analysis of phosphorylated factor VIII by casein kinase II showed the presence of phosphothreonine as well as small amounts of phosphoserine. The platelet kinase responsible for the phosphorylation of the two cofactors was found to be inhibited by several synthetic protein kinase inhibitors. Finally, partially phosphorylated factor Va was found to be more sensitive to APC inactivation than its native counterpart. Our findings suggest that phosphorylation of factors Va and VIIIa by a platelet casein kinase II- like kinase may downregulate the activity of the two cofactors.  相似文献   
89.
Effect of HCV NS3 protein on P53 protein expression in hepatocarcinogenesis   总被引:14,自引:0,他引:14  
NTRODUCTIONHepatocelularcarcinoma(HCC)isoneofthemostcommonhumancancersintheworld.Recently,theHCVinfectionwasfoundtobeanetiolo...  相似文献   
90.
NTRODUCTIONApoptosisisanimportantphysiologicalformofceldeath.Itisstrictlycontroledbygenes.Ithasbeenshowninexperimentsthatexte...  相似文献   
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