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Graefe's Archive for Clinical and Experimental Ophthalmology - To estimate the impact of delayed care during the coronavirus disease 2019 (COVID-19) pandemic on the outcomes of patients with...  相似文献   
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Cholangiocarcinoma(CCA) is a malignant tumor of the biliary system and includes, according to the anatomical classification, intra hepatic CCA(iCCA),hilar CCA(hCCA) and distal CCA(dCCA). Hilar CCA is the most challenging type in terms of diagnosis, treatment and prognosis. Surgery is the only treatment possibly providing long-term survival, but only few patients are considered resectable at the time of diagnosis. In fact, tumor's extension to segmentary or subsegmentary biliary ducts, along with large lymph node involvement or intrahepatic metastases, precludes the surgical approach. To achieve R0 margins is mandatory for the disease-free survival and overall survival. In case of unresectable locally advanced hCCA, radiochemotherapy(RCT) as neoadjuvant treatment demonstrated to be a therapeutic option before either hepatic resection or liver transplantation. Before liver surgery, RCT is believed to enhance the R0 margins rate. For patients meeting the Mayo Clinic criteria, RCT prior to orthotopic liver transplant(OLT) has proved to produce acceptable 5-years survivals. In this review, we analyze the current role of neoadjuvant RCT before resection as well as before OLT.  相似文献   
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Background

Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.

Methods

We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).

Results

Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.

Conclusions

Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.  相似文献   
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BACKGROUND: The activity and isoenzyme composition of N-acetyl-beta-D-hexosaminidase (EC.3.2.1.52) in seminal plasma of fertile and infertile men have been evaluated. However, no data are available on the isoenzyme content in seminal plasma from patients with secretory azoospermia. METHODS: The activity and isoenzyme composition of seminal plasma from 15 normozoospermic controls and 18 patients with secretory azoospermia were determined by fluorimetric methods. 4-Methylumbelliferil-2-acetamido-2-deoxy-beta-D-glucopyranoside and 4-methylumbelliferil-2-acetamido-2-deoxy-beta-D-glucopyranoside-6-sulfate were used as fluorigenic substrates. Receiver-operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic efficiency of the assays. RESULTS: No significant difference was found in total enzyme activity between the two groups, while isoenzyme A activity was significantly lower (p=0.004) and the ratio between total enzyme activity and isoenzyme A activity was significantly higher (p=0.04) in azoospermic patients compared to controls. The diagnostic efficiency of these evaluations was low (< or =75.7%). CONCLUSIONS: Our findings show that the isoenzyme composition of N-acetyl-beta-D-hexosaminidase in seminal plasma from patients with secretory azoospermia is significantly different from controls, but this difference does not represent a useful marker of secretory azoospermia. The fluorimetric assays are simple and rapid methods for evaluating the isoenzyme composition.  相似文献   
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The application of a circular dichroism (c.d.) detection system in HPLC using a chiral stationary phase is presented. The simultaneous measurement of the absorbance and c.d. signal allows the evaluation of the anisotropy factor (g = Δ/) and thus the determination of the enantiomeric excess (e.e.) of the eluates. When this detection system is used in preparative chiral chromatography the collection of the enantiomeric fractions can be readily optimized.  相似文献   
9.
Aim There is a controversy as to whether dyslexic children present visuo-motor disabilities such as vergence and accommodative problems assessed with orthoptic tests. The purpose of this study is to re-examine this issue in a large population of children. Methods Extensive orthoptic evaluation was made in 57 dyslexic and 46 non-dyslexic (“normal”) age-matched children. Convergence and divergence capacities were evaluated at two distances (30 cm and 400 cm). Results Binocular vision measured with stereo-acuity tests was normal in dyslexics. In contrast, the near point of convergence was significantly more remote in dyslexics; most importantly, divergence at both far and near distance was significantly more reduced in dyslexics (median value 4 pD and 10 pD, respectively, at far and near) than in “normals” (median value 6 pD and 12 pD, at far and near). Conclusion The existence of the divergence deficit at far distance indicates the presence of deficit of divergence per se, independently from convergence and accommodation relaxation. This result is novel and corroborated by physiological studies indicating distinct control of convergence and divergence, both at the cortical and subcortical premotor level. We conclude that vergence deficits are frequently present in dyslexics, and that dyslexics should be re-educated; training should address distinctively convergence and divergence subsystems.  相似文献   
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BACKGROUND: Cardiac magnetic resonance (MR) images are often reviewed by non-cardiologists who are not trained in the interpretation of regional left ventricular (LV) function. We hypothesized that the use of still-frame parametric MR images of wall motion could aid in the assessment of regional LV function. METHODS: Dynamic, electrocardiogram-gated, steady-state free precession (FIESTA) short-axis images were obtained in 6 to 10 slices in 18 consecutive patients. Each loop was used to automatically generate a still-frame image, in which each pixel is assigned a value equal to the amplitude of cyclic variation in local intensity, resulting in higher intensity in pixels that change between blood and tissue during the cardiac cycle. The dynamic images were reviewed by an expert cardiologist who provided gold standard grades for regional wall motion and by four radiologists. Then the radiologists reviewed and graded the same MR images in combination with parametric images. Grades assigned to each segment in the two sessions were compared with the gold standard. RESULTS: According to expert interpretation, 6 patients had normal wall motion, and 12 had wall motion abnormalities. Parametric images showed a bright band in the area spanned by endocardial motion, with reduced brightness and thickness in areas of hypokinesis. The agreement between the radiologists' grades and the gold standard significantly improved by adding parametric images (from 77% to 81%), which also resulted in reduced interobserver variability (from 52% to 33%). CONCLUSIONS: Still-frame parametric images aid in the assessment of regional wall motion by non-cardiologists who are required to interpret cardiac images.  相似文献   
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