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61.
We have evaluated the fibrinogen/fibrin fragment E antigen assay as a diagnostic test in patients with clinically suspected venous thrombosis by comparing the results of this assay with venography in 272 patients. The result of the fragment E antigen assay was elevated in 79 of 80 patients with positive venograms for recent venous thrombosis (sensitivity 99%) and within the normal range in 161 of 192 patients with normal venograms (specificity 84%). The fragment E assay was also evaluated in 130 medical and surgical controls without evidence of venous thrombosis by leg scanning and the test was found to be relatively nonspecific. However, in the patient group under study, a correct clinical diagnosis of no thrombosis, based on a normal fragment E result, was made in 161 of 162 cases (negative predictive value of 99%). Therefore, a normal test result effectively excludes a diagnosis of venous thrombosis in clinically symptomatic patients. The assay, as currently performed, is technically demanding and takes 24 hr to complete. Therefore, it will have to be simplified before it can be applied to clinical practice.  相似文献   
62.
Objective: To define modified Prenatal Growth Assessment Scores (mPGAS) for single and composite biometric parameters and determine their reference ranges in normal fetuses.

Methods: Nine anatomical parameters (ap) were measured and the weight estimated (EWTa, EWTb) in a longitudinal study of 119 fetuses with normal neonatal growth outcomes. Expected third trimester size trajectories, obtained from second trimester Rossavik size models, were used in calculating Percent Deviations (% Dev's) and their age-specific reference ranges in each fetus. The components of individual % Dev's values outside their reference ranges, designated +iapPGAS, -iapPGAS, were averaged to give +apPGAS and ?apPGAS values for the 3rd trimester. The +iapPGAS and ?iapPGAS values for different combinations of ap (c1a (HC, AC, FDL, ThC, EWTa), c1b (HC, AC, FDL, ThC, EWTb), c2 (ThC, ArmC, AVol, TVol), c3 (HC, AC, FDL, EWTa)) were then averaged to give +icPGAS and ?icPGAS values at different time points or at the end of the third trimester (+cPGAS, ?cPGAS). Values for iapPGAS, ic1bPGAS, and ic2PGAS were compared to their respective apPGAS or cPGAS reference ranges.

Results: All mPGAS values had one 95% range boundary at 0.0%. Upper boundaries of 1D +apPGAS values ranged from 0.0% (HC) to +0.49% (ThC) and were +0.06%, +2.3% and +1.8% for EWT, AVol and TVol, respectively. Comparable values for ?apPGAS were 0.0% (BPD, FDL, HDL), to ?0.58% (ArmC), ?0.13% (EWT), ?0.8% (AVol), and 0.0% (TVol). The +cPGAS, 95% reference range upper boundaries varied from +0.36% (c1b) to +0.89% (c2). Comparable values for ?cPGAS lower boundaries were ?0.17% (c1b) to ?0.43% (c2).

Conclusions: The original PGAS concept has now been extended to individual biometric parameters and their combinations. With the standards provided, mPGAS values can now be tested to see if detection of different types of third trimester growth problems is improved.  相似文献   

63.
Journal of Thrombosis and Thrombolysis - Patients with Moyamoya disease (MMD) can present with ischaemic or haemorrhagic stroke. There is no good evidence for treatment strategies in MMD-associated...  相似文献   
64.
The recent rapid increase in the prevalence of obesity across the world is undoubtedly due to changes in diet and lifestyle. However, it is also indisputable that different people react differently to this change in environment and this variation in response is likely to be genetically determined. While for the majority of people this effect is presumed to be polygenic in origin, there is now strong evidence for a small number of genes having a large effect in some families with severe obesity. Studies of these families, coupled with parallel studies in murine models, have provided novel insights into the molecules involved in the regulation of appetite, energy expenditure and nutrient partitioning. We review here the lessons we have learnt from mouse models of obesity, both naturally occurring and artificially generated through targeted gene deletions, and more importantly from human monogenic syndromes of obesity. These have illuminated the critical role in which the central leptin melanocortin pathway plays in the control of mammalian food intake and body weight.  相似文献   
65.
66.
ERCC1-XPF is a multifunctional endonuclease involved in nucleotide excision repair (NER), interstrand cross-link (ICL) repair, and DNA double-strand break (DSB) repair. Only two patients with bi-allelic ERCC1 mutations have been reported, both of whom had features of Cockayne syndrome and died in infancy. Here, we describe two siblings with bi-allelic ERCC1 mutations in their teenage years. Genomic sequencing identified a deletion and a missense variant (R156W) within ERCC1 that disrupts a salt bridge below the XPA-binding pocket. Patient-derived fibroblasts and knock-in epithelial cells carrying the R156W substitution show dramatically reduced protein levels of ERCC1 and XPF. Moreover, mutant ERCC1 weakly interacts with NER and ICL repair proteins, resulting in diminished recruitment to DNA damage. Consequently, patient cells show strongly reduced NER activity and increased chromosome breakage induced by DNA cross-linkers, while DSB repair was relatively normal. We report a new case of ERCC1 deficiency that severely affects NER and considerably impacts ICL repair, which together result in a unique phenotype combining short stature, photosensitivity, and progressive liver and kidney dysfunction.  相似文献   
67.

Purpose

Other than a single case report, no diffusion tensor tractography (DTT) studies of the precommissural fornix in the human brain have been conducted. In the current study, we attempted to visualize the precommissural fornix in the human brain using DTT.

Materials and Methods

We recruited 36 healthy volunteers for this study. Diffusion tensor images were scanned using a 1.5-T scanner, and the precommissural fornix was analyzed using Functional Magnetic Resonance Imaging of the Brain (FMRIB) software. Values of fractional anisotropy (FA), mean diffusivity (MD), and tract volume of the precommissural fornix were measured.

Results

The precommissural fornix originated from the hippocampal formation on each hemisphere as a crus; both crura were then joined to the body of the fornix. The body of the fornix continued anteriorly to the level just superior to the anterior commissure, where it divided into each column of the precommissural fornix. Each column descended anteriorly to the anterior commissure and terminated in the septal nuclei. Values of FA, MD, and tract volumes of the precommissural fornix did not differ between the right and left hemispheres (p>0.05).

Conclusion

We believe that the methodology and results of this study would be helpful to future research on the precommissural fornix and in the elucidation of the pathology of diseases involving the precommissural fornix.  相似文献   
68.
69.
PURPOSEThe purpose of this in vitro study was to investigate the wear resistance and surface roughness of three interim resin materials, which were subjected to chewing simulation.MATERIALS AND METHODSThree interim resin materials were evaluated: (1) three-dimensional (3D) printed (digital light processing type), (2) computer-aided design and computer-aided manufacturing (CAD/CAM) milled, and (3) conventional polymethyl methacrylate interim resin materials. A total of 48 substrate specimens were prepared. The specimens were divided into two subgroups and subjected to 30,000 or 60,000 cycles of chewing simulation (n = 8). The wear volume loss and surface roughness of the materials were compared. Statistical analysis was performed using one-way analysis of variance and Tukey''s post-hoc test (α=.05).RESULTSThe mean ± standard deviation values of wear volume loss (in mm3) against the metal abrader after 60,000 cycles were 0.10 ± 0.01 for the 3D printed resin, 0.21 ± 0.02 for the milled resin, and 0.44 ± 0.01 for the conventional resin. Statistically significant differences among volume losses were found in the order of 3D printed, milled, and conventional interim materials (P<.001). After 60,000 cycles of simulated chewing, the mean surface roughness (Ra; μm) values for 3D printed, milled, and conventional materials were 0.59 ± 0.06, 1.27 ± 0.49, and 1.64 ± 0.44, respectively. A significant difference was found in the Ra value between 3D printed and conventional materials (P=.01).CONCLUSIONThe interim restorative materials for additive and subtractive manufacturing digital technologies exhibited less wear volume loss than the conventional interim resin. The 3D printed interim restorative material showed a smoother surface than the conventional interim material after simulated chewing.  相似文献   
70.
Stroke rehabilitation is labor-intensive and time-consuming. To assist patients and therapists alike, we propose a wearable system that measures orientation and corrects arm posture using vibrotactile actuators. The system evaluates user posture with respect to a reference and gives feedback in the form of vibration patterns. Users correct their arm posture, one DOF at a time, by following a protocol starting from the shoulder up to the forearm. Five users evaluated the proposed system by replicating ten different postures. Experimental results demonstrated system robustness and showed that some postures were easier to mimic depending on their naturalness.  相似文献   
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