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61.
BackgroundForce‐time integral (FTI) is an ablation marker of lesion quality and transmurality. A target FTI of 400 gram‐seconds (gs) has been shown to improve durability of pulmonary vein isolation, following atrial fibrillation ablation. However, relevant targets for cavotricuspid isthmus (CTI) ablation are lacking.HypothesisWe sought to investigate whether CTI ablation with 600 gs FTI lesions is associated with reduced rate of transisthmus conduction recovery compared to 400 gs lesions.MethodsFifty patients with CTI‐dependent flutter were randomized to ablation using 400 gs (FTI400 group, n = 26) or 600 gs FTI lesions (FTI600 group, n = 24). The study endpoint was spontaneous or adenosine‐mediated recovery of transisthmus conduction, after a 20‐min waiting period.ResultsThe study endpoint occurred in five patients (19.2%) in group FTI400 and in four patients (16.7%) in group FTI600, p = .81. First‐pass CTI block was similar in both groups (50% in FTI400 vs. 54.2% in FTI600, p = .77). There were no differences in the total number of lesions, total ablation time, procedure time and fluoroscopy duration between the two groups. There were no major complications in any group. In the total population, patients not achieving first‐pass CTI block had significantly higher rate of acute CTI conduction recovery, compared to those with first‐pass block (29.2% vs. 7.7% respectively, p = .048).ConclusionsCTI ablation using 600 gs FTI lesions is not associated with reduced spontaneous or adenosine‐mediated recurrence of transisthmus conduction, compared to 400 gs lesions.  相似文献   
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BACKGROUND: Many members of the human kallikrein gene family are differentially expressed in cancer and a few have potential as diagnostic/prognostic markers. KLK14 is a newly discovered human kallikrein gene that is mainly expressed in the central nervous system and endocrine tissues. Since KLK14 was found to be regulated by steroid hormones in prostate cancer cell lines, we hypothesized that it will be differentially expressed in prostate cancer tissues compared to their normal counterparts. METHODS: Matched prostate tissue samples from the cancerous and non-cancerous parts of the same prostates were obtained from 100 patients who underwent radical prostatectomy. Quantitative analysis of KLK14 expression levels were performed by real-time RT-PCR using SYBR Green I dye on the LightCycler trade mark system. Associations with clinico-pathological parameters were analyzed. RESULTS: KLK14 overexpression in the cancerous compared to non-cancerous tissue was found in 74% of patients (P < 0.001). Mean level of expression was 154 arbitrary units (Au) in cancerous tissues and 14.2 Au in the non-cancerous tissues. The ratio of the cancerous to non-cancerous KLK14 expression values was higher in patients with late stage (stage III) compared to stage II (P = 0.002), and in grade 3 compared to grade 1/2 tumors (P = 0.001). A statistically significant increase was also observed in patients with higher in Gleason score (>6) compared to Gleason score = 6 tumors (P = 0.027). No correlation was found between KLK14 tissue expression levels and serum prostate-specific antigen. CONCLUSIONS: KLK14 expression is significantly higher in cancerous compared to non-cancerous prostatic tissue. The up-regulation of the KLK14 gene in advanced and more aggressive tumors may indicate a possible role for the hK14 protein in tumor spread and opens the possibility of hK14 being a candidate new marker for prostate cancer diagnosis and prognosis.  相似文献   
63.
PurposeThe purpose of the present study was to evaluate the visibility and the image quality of the biliary and pancreatic duct system on magnetic resonance cholangiopancreatography (MRCP) images based on two breath-hold (BH) methods using array spatial sensitivity technique: a single-shot fast spin-echo (SS-FSE) sequence and a three-dimensional single slab fast spin-echo (3D-FSE) sequence.Materials and methodsIn the present prospective comparative study, 47 patients (22 male and 25 female, mean age=50 years, age range=22–82 years) that were referred for MRCP during a 12-month period are included. All of them were referred with suspected pancreaticobiliary disease. All patients underwent MRCP with both a SS-FSE BH sequence and a 3D-FSE BH sequence. Qualitative evaluation regarding the depiction of three segments of the pancreaticobiliary tree and the frequency of artifacts was performed. Two radiologists graded each sequence of the obtained studies in a blinded fashion. Quantitative evaluation including calculation of relative signal intensity (rSI) and relative contrast (RC) ratios at seven segments of the pancreaticobiliary tree between fluid-filled ductal structures and organ parenchyma at the same ductal segments was performed. In order to evaluate the parameters' differences of the two sequences, either in qualitative or in quantitative analysis, the Wilcoxon paired signed-rank test was performed.ResultsOn quantitative evaluation, both rSI and RC ratios of all segments of the pancreaticobiliary tree at SS-FSE BH sequence were higher than those at 3D-FSE BH sequences. This finding was statistically significant (P< .01). On qualitative evaluation, the two radiologists found intrahepatic ducts and pancreatic ducts to be better visualized with SS-FSE BH than with 3D-FSE BH sequence. This finding was statistically significant (P< .02). One of them found extrahepatic ducts to be significantly better visualized with SS-FSE BH sequence. Moreover, the frequency of artifacts was lower in the SS-FSE sequence, a finding that was of statistical significance. Interobserver agreement analysis found at least substantial agreement (κ>0.60) between the two radiologists.ConclusionThe SS-FSE sequence is performed faster and significantly improves image quality; thus, it should be included into the routine MRCP sequence protocol at 3.0 T. Furthermore, we recommended SS-FSE BH MRCP examination to be applied to uncooperative patients or patients in emergency because of its short acquisition time (1 s).  相似文献   
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Aim: Τo determine the prevalence of impacted teeth in an adult Greek population, according to type, sex, and age. Methods: The major source of data for this study was the orthopantomographic films and the physical examinations of 425 patients (202 males and 223 females) with impacted teeth. The elements that were examined and processed were relevant to the age, sex, total number of impacted teeth, and the type and frequency of impaction of each tooth. Moreover, the associated pathology, if any, of the impacted tooth was recorded. Results: A total of 152 patients (35.8%) had one impacted tooth, 134 patients (31.5%) had two impacted teeth, and 139 patients (32.7%) had three or more impacted teeth; 777 (82.7%) impacted teeth revealed associated pathology. Conclusions: The third molars revealed the highest frequency of impaction (P < 0.001); the number of impacted teeth of the mandible was larger than that of the maxilla (P < 0.001), and the number of impacted anterior teeth in the maxilla was larger than that in the mandible (P < 0.001). Cases of impacted posterior teeth were more numerous than anterior teeth (P < 0.001). The majority of patients revealed pathological signs, which dictated the surgical removal of the impacted tooth/teeth.  相似文献   
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PURPOSE: Our goal was to examine a panel of 11 biochemical variables, measured in cytosolic extracts of ovarian tissues (normal, benign, and malignant) by quantitative ELISAs for their ability to diagnose, prognose, and predict response to chemotherapy of ovarian cancer patients. EXPERIMENTAL DESIGN: Eleven proteins were measured (9 kallikreins, B7-H4, and CA125) in cytosolic extracts of 259 ovarian tumor tissues, 50 tissues from benign conditions, 35 normal tissues, and 44 tissues from nonovarian tumors that metastasized to the ovary. Odds ratios and hazard ratios and their 95% confidence interval were calculated. Time-dependent receiver operating characteristic curves for censored survival data were used to evaluate the performance of the biomarkers. Resampling was used to validate the performance. RESULTS: Most biomarkers effectively separated cancer from noncancer groups. A composite marker provided an area under the curve of 0.97 (95% confidence interval, 0.95-0.99) for discriminating normal and cancer groups. Univariately, hK5 and hK6 were positively associated with progression. After adjusting for clinical variables in multivariate analysis, both hK10 and hK11 significantly predicted time to progression. Increasing levels of hK13 were associated with chemotherapy response, and the predictive power of hK13 to chemotherapy response was improved by a panel of five biomarkers. CONCLUSIONS: The evidence shows that a group of kallikreins and multiparametric combinations with other biomarkers and clinical variables can significantly assist with ovarian cancer classification, prognosis, and response to platinum-based chemotherapy. In particular, we developed a multiparametric strategy for predicting ovarian cancer response to chemotherapy, comprising several biomarkers and clinical features.  相似文献   
67.
A 45-year-old man presented with clinical manifestations of foveomacular retinitis, including visual symptoms and foveal lesions characteristic of solar retinopathy, but repeated questions failed to elicit a history of sun gazing. Cross-sectional retinal images produced by optical coherence tomography revealed localized loss of retinal pigment epithelium cells in both eyes. A different pattern of reflectivity at the level of the photoreceptor layer was observed between the right and left eye, reflecting asymmetry in tissue damage. This case is described to provide additional evidence that solar retinopathy and foveomacular retinitis are the same entity and may also have common optical coherence tomography findings.  相似文献   
68.
Prostate specific antigen (PSA) is a tumor marker used widely for the diagnosis and monitoring of prostatic adenocarcinoma. Recently, we provided evidence that PSA may also be produced by breast tumors. In this report we examined quantitatively the PSA levels in 199 breast tumors, 48 tissues with benign breast disease (BBD, 34 fibroadenomas), and 36 normal breast tissues. Significant amounts of PSA (≥ 0.030 ng of PSA per mg of total protein) were found in 28% of breast tumors, 65% of BBD tissues, and 33% of normal breast tissues. PSA positivity in breast tumors was highest in stage I disease (34%) and decreased with disease stage (24% in stage II and 18% in stage III–IV). Using polymerase chain reaction amplification we have shown PSA mRNA presence in patients with PSA protein-positive tissues (benign and malignant) but not in patients with PSA protein-negative tissues. Our data suggest that PSA is expressed frequently by normal breast tissue, by tissue of benign breast diseases, and by breast cancer tissue. Highest expression is seen in benign breast disease and lowest expression in advanced stage cancerous tissue. As PSA production is mediated by steroid hormones and their receptors, we propose that PSA may be a new marker of steroid hormone action in the normal or diseased female breast. The role of this enzyme in the development of breast diseases including breast cancer is currently unknown.  相似文献   
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