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41.
BACKGROUND/AIMS: Skeletal metastasis in hepatocellular carcinoma patients has become clinically important as a result of advances in treatment modalities. However, the diagnostic accuracy of bone scintigraphy in hepatocellular carcinoma has been questioned. METHODOLOGY: 99mTc-MDP bone scintigraphy was performed in 63 unresectable hepatocellular carcinoma patients treated by transcatheter arterial embolization who either developed musculoskeletal pain (n = 43) or elevated serum alpha-fetoprotein levels (n = 20) during follow-up. Results were categorized as positive or negative for metastases, and their accuracy was evaluated by radiological studies, biopsy, and clinical follow-up. RESULTS: Bone scintigraphy was positive in 22/43 (51.2%) subjects with pain and 2/20 with alpha-feto-protein elevation. Among 24 bone scintigraphy(+) patients, metastasis was confirmed in 17 and excluded in 6. Frequent sites for metastatic bone scintigraphy lesions were the spine, pelvic bone and ribs. Although 8 metastatic lesions had low or mixed uptake, most had increased uptake on bone scintigraphy. Among 39 bone scintigraphy(-) patients, metastasis was excluded in 32 and confirmed in 1. The sensitivity and specificity of bone scintigraphy in this subset of patients was 94.4% and 84.2%, respectively. CONCLUSIONS: Transcatheter arterial embolization treated hepatocellular carcinoma patients with musculoskeletal pain have a high likelihood of bone metastasis, and bone scintigraphy is a highly reliable method for its detection.  相似文献   
42.
The vanadate-based phosphors Sr2V2O7:Eu3+ (SV:Eu3+), Sr9Gd(VO4)7:Eu3+ (SGV:Eu3+) and Sr9Gd(VO4)7/Sr2V2O7:Eu3+ (SGV/SV:Eu3+) were obtained by solid-state reaction. The bond-energy method was used to investigate the site occupancy preference of Eu3+ based on the bond valence model. By comparing the change of bond energy when the Eu3+ ions are incorporated into the different Sr, V or Gd sites, we observed that Eu3+ doped in SV, SGV or SV/SGV would preferentially occupy the smaller energy variation sites, i.e., Sr4, Gd and Gd sites, respectively. The crystal structures of SGV and SV, the photoluminescence properties of SGV:Eu3+, SV, SGV/SV and SGV/SV:Eu, as well as their possible energy transfer mechanisms are proposed. Interesting tunable colours (including warm-white emission) of SGV/SV:Eu3+ can be obtained through changing the concentration of Eu3+ or changing the relative quantities of SGV to SV by increasing the calcination temperature. Its excitation bands consist of two types of O2− → V5+ charge transfer (CT) bands with the peaks at about 325 and 350 nm respectively, as well as f–f transitions of Eu3+. The obtained warm-white emission consists of a broad photoluminescence band centred at about 530 nm, which originates from the O2− → V5+ CT of SV, and a sharp characteristic spectrum (5D07F2) at about 615 and 621 nm.

The vanadate-based phosphors Sr2V2O7:Eu3+ (SV:Eu3+), Sr9Gd(VO4)7:Eu3+ (SGV:Eu3+) and Sr9Gd(VO4)7/Sr2V2O7:Eu3+ (SGV/SV:Eu3+) were obtained by solid-state reaction.  相似文献   
43.
In many randomized controlled trials, treatment groups are of equal size, but this is not necessarily the best choice. This paper provides a methodology to calculate optimal treatment allocations for longitudinal trials when we wish to compare multiple treatment groups with a placebo group, and the comparisons may have unequal importance. The focus is on trials with a survival endpoint measured in discrete time. We assume the underlying survival process is Weibull and show that values for the parameters in the Weibull distribution have an impact on the optimal treatment allocation scheme in an interesting way. Additionally, we incorporate different cost considerations at the subject and measurement levels and determine the optimal number of time periods. We also show that when many events occur at the beginning of the trial, fewer time periods are more efficient. As an application, we revisit a risperidone maintenance treatment trial in schizophrenia and use our proposed methodology to redesign it and compare merits of our optimal design. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
44.

Purpose

To investigate the effects of laser suture lysis (LSL) on filtration openings after trabeculectomy.

Methods

Prospective study analyzing the changes in the location and width of filtration openings, fluid cavity height, total bleb height, bleb wall thickness, and bleb wall intensity before and after LSL using three-dimensional anterior segment optical coherence tomography (3D AS-OCT).

Results

Fourteen patients had clear scleral flap image analysis. As five patients underwent LSL twice and two patients underwent LSL thrice, 23 comparison studies were possible. After LSL the intraocular pressure (IOP) decreased (P=0.0015) from 20.5±5.3 to 14.9±6.4 mm Hg, and the fluid cavity height increased significantly from 0.2±0.2 mm to 0.3±0.1 mm (P=0.0094). Other bleb parameters were not significantly different when comparing before and after LSL. When the IOP reduction ratio was >25% following LSL, the width of the filtration openings on the LSL side, the total bleb height, and the fluid cavity height increased (P=0.0273, 0.0342, and 0.0024, respectively). In multiple regression analysis the changes in fluid cavity height, the wall thickness, the wall intensity, and the width of the filtration opening were positively associated with the IOP reduction rate (P=0.0428, 0.0226, 0.0420, and 0.0356, respectively).

Conclusions

3D AS-OCT allowed a detailed examination of the internal morphology of filtration blebs and openings before and after LSL. The changes in the internal morphology were closely associated with the success of LSL to decrease IOP.  相似文献   
45.
Foreign bodies in the colon are encountered with increasing frequency, but only sporadic reports concerning their management have appeared in the literature. While most ingested foreign bodies usually pass through the gastrointestinal tract uneventfully, sharp foreign bodies such as toothpicks infrequently cause intestinal perforation and may even result in death. We report our experience with a patient with a sigmoid colon pseudodiverticulum formation, a complication of accidental ingestion of a toothpick that was diagnosed and successfully managed colonoscopically.  相似文献   
46.
To assess whether there is a differential hypocholesterolemic response to weight loss for subjects carrying polymorphisms of the apolipoprotein B and other genes. A before and after comparison of lipid parameters following a calorie controlled diet for an intervention period of 12 weeks. A lipid clinic based in a large teaching hospital. The difference in slope coefficients relating the percentage change in lipid parameters to the change in body weight (adjusted for age, gender and initial body mass index (BMI)), for genotype subgroups defined by polymorphisms of the 5'VNTR apoB gene, two mutations of the LPL gene and ApoE. One hundred and forty six subjects completed the intervention diet. While, on average, the intervention was successful (mean weight loss 3.9%), there was no statistically significant difference in the slope coefficients relating lipid change to weight loss for most of the genotypes tested. The slope difference for long versus short 5'VNTR alleles of the apoB gene was 0.445 (-1.307, 2.198) for apolipoprotein B and -0. 104 (-1.486, 1.278) for total cholesterol. However, subjects carrying at least one varepsilon4 allele were significantly hypo-responsive to weight loss, difference in slope coefficients -1.087 (-2.09, -0.084) and -1.320 (-2.589, 0.051) for total cholesterol and apoB, respectively. Although, this study is one of the largest of its kind, it has not replicated the findings of other smaller studies. These findings do not provide support for the use of genotype-targeted dietary advice in routine practice.  相似文献   
47.
Endoscopic detection of early upper GI cancers   总被引:3,自引:0,他引:3  
The detection of early-stage neoplastic lesions in the upper GI tract is associated with improved survival and the potential for complete endoscopic resection that is minimally invasive and less morbid than surgery. Despite technological advances in standard white-light endoscopy, the ability of the endoscopist to reliably detect dysplastic and early cancerous changes in the upper GI tract remains limited. In conditions such as Barrett's oesophagus, practice guidelines recommend periodic endoscopic surveillance with multiple biopsies, a methodology that is hindered by random sampling error, inconsistent histopathological interpretation, and delay in diagnosis. Early detection may be enhanced by several promising diagnostic modalities such as chromoendoscopy, magnification endoscopy, and optical spectroscopic/imaging techniques, as these modalities offer the potential to identify in real-time lesions that are inconspicuous under conventional endoscopy. The combination of novel diagnostic techniques and local endoscopic therapies will provide the endoscopist with much needed tools that can considerably enhance the detection and management of early stage lesions in the upper GI tract.  相似文献   
48.
Adenosquamous carcinoma of the papilla of Vater is a rare tumor and only a few cases have been reported so far. Here, we report a case of adenosquamous carcinoma in a 76-year-old male who presented with jaundice and right upper quadrant abdominal pain. Ultrasonography and enhanced abdominal CT scans showed dilated common bile duct (CBD) and intrahepatic bile duct (IHD) with a suspicious obstructing mass in distal CBD. On endoscopy, obstructing and ulcerated mass was noted on the papilla of Vater. Histopathological inspection of the biopsied specimens from mass showed adenosquamous cell carcinoma of the papilla of Vater. Since the patient refused operation, we inserted a self-expandable metallic stent in distal CBD. This is the first case report on adenosquamous carcinoma of the papilla of Vater in Korea.  相似文献   
49.
BACKGROUND: Non-alcoholic fatty liver disease is a common reason for hepatological consultation and may herald severe hepatic and extra-hepatic disease. The aetiopathogenesis of this condition is an area of increasing interest. AIM: To evaluate anthropometric and biochemical factors associated to non-alcoholic fatty liver disease in a case-control study. Methods. Demographic and biochemical data of 60 consecutive patients with bright liver absent-to-low alcohol consumption, no evidence of viral, genetic and autoimmune diseases, were compared to those of 60 age- and gender-matched historical controls without fatty liver by univariate and multiple logistic regression analysis. RESULTS: Patients were more often hypertriglyceridaemic, obese and diabetic than controls (p<.01). Mean values of alanine transaminase, gammaglutamyltranspeptidase, triglycerides, uric acid, fasting and log insulin, transferrin percent saturation and ferritin were significantly higher in the patients, while transferrin and quantitative insulin sensitivity check index, a quantitative insulin sensitivity index, were lower. No iron storage was found in those who underwent liver biopsy At univariate analysis the relative risk for non-alcoholic fatty liver disease significantly increased (p<0. 05) with increasing body mass index, fasting insulin, alanine transaminase, uric acid, triglycerides and gammaglutamyltranspeptidase; it decreased with increasing transferrin and quantitative insulin sensitivity check index. Multiple logistic regression analysis disclosed only fasting insulin and uric acid to be independent predictors of non-alcoholic fatty liver disease (p<0.05). CONCLUSIONS: Fasting insulin and serum uric acid levels indicating insulin resistance, but not indices of iron overload, are independent predictors of non-alcoholic fatty liver disease.  相似文献   
50.
BACKGROUND AND AIMS: The (13)C-urea breath test ((13)C-UBT) is a reliable non-invasive method of diagnosing Helicobacter pylori infection in adults and children. However, only a few validation studies have been performed on the (13)C-UBT in very young children. The purpose of the present study was to evaluate the diagnostic accuracy of the (13)C-UBT according to age, and to determine the optimal cut-off value in children. METHODS: A total of 307 (13)C-UBT were performed in 274 children. All were compared with the results of endoscopic biopsy-based methods to confirm H. pylori infection. Seventy-five milligrams of (13)C-urea was ingested without a test meal. Two breath samples were collected at 0 and 30 min. The optimal cut-off value of the (13)C-UBT was assessed by determining the sensitivity, specificity, false negative, and false positive results, at cut-off values ranging from 2.0 to 10.0 per thousand. RESULTS: The delta over baseline (DOB) values of the (13)C-UBT showed a significant negative correlation with age in both the H. pylori-positive group (r = -0.309; P = 0.005) and the H. pylori-negative group (r = -0.162; P = 0.015). High false positive results and low specificity were noted in children aged 6 years or less compared with children older than 6 years at a cut-off value of 4.0 per thousand (false positives; 8.3%vs 0.85%, specificity; 89.8%vs 98.8%). After adjusting the cut-off value, the optimal cut-off values were found to be 4.0 per thousand in children older than 6 years and 7.0 per thousand in children aged 6 years or less. CONCLUSIONS: The cut-off value of the (13)C-UBT recommended regardless of age must be adjusted in preschool children to reduce the false positive results.  相似文献   
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