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Enamel Hypoplasia (EH) is known to be a useful indicator for wide range of detrimental factors in early childhood in past populations, such as nutritional disturbances, mechanical trauma, disease, metabolic, and/or genetic disorders. EH may be divided into three categories: pits, grooves, and lines, where the last two are referred to as “Linear Enamel Hypoplasia” (LEH). The regularity of enamel formation allows retrospective determination of the age of LEH formation. The current article reviews and compares the best-known methods used to estimate age at LEH formation and provides a new computational tool. Growth curves for canines and incisors were developed based on tooth growth tables by previous authors. Optimal models were selected using the Akaike Information Criterion. A Microsoft Excel spreadsheet was created to calculate age at LEH formation using the most common methods. All method results were compared with an archaeological sample (44 teeth of 18 individuals from an early modern cemetery from Wrocław, Poland) and a theoretical model. The results of the methods were compared pairwise with Bland-Altman plots. The current article provides a quick and easy-to-use tool for analyzing LEH chronology and comparing the results of different methods. As shown by the Bland-Altman plots, most methods provide approximately consistent results for LEHs formed at around 2–3 years of age. However, LEHs formed particularly early or late are more prone to discrepancies between different methods. Comparison of the age at LEH formation obtained by different methods should be done carefully - and the new LEH calculation tool with optimized equations provided in this publication can facilitate this process.  相似文献   
996.
The current study aims to investigate visual scene perception and its neuro-anatomical correlates for stimuli presented in the central visual field of patients with homonymous hemianopia, and thereby to assess the effect of a right or a left occipital lesion on brain reorganization. Fourteen healthy participants, three left brain damaged (LBD) patients with right homonymous hemianopia and five right brain damaged (RBD) patients with left homonymous hemianopia performed a visual detection task (i.e. “Is there an image on the screen?”) and a categorization task (i.e. “Is it an image of a highway or a city?”) during a block-designed functional magnetic resonance imaging recording session. Cerebral activity analyses of the posterior areas—the occipital lobe in particular—highlighted bi-hemispheric activation during the detection task but more lateralized, left occipital lobe activation during the categorization task in healthy participants. Conversely, in patients, the same network of activity was observed in both tasks. However, LBD patients showed a predominant activation in their right hemisphere (occipital lobe and posterior temporal areas) whereas RBD patients showed a more bilateral activation (in the occipital lobes). Overall, our preliminary findings suggest a specific pattern of cerebral activation depending on the task instruction in healthy participants and cerebral reorganization of the posterior areas following brain injury in hemianopic patients which could depend upon the side of the occipital lesion.  相似文献   
997.

Purpose

The aim of this study was to evaluate the dimensions (maximal width and length), the size and the shape of the PA and their sexual dimorphism.

Methods

Using 3D-CT scan reconstructions and landmarks positioning around the piriform aperture and on the face, a collective of 170 non-pathologic subjects (79 female, 91 male) from Marseille (France) was examined in classical and geometric morphometrics methods.

Results

The mean width of the piriform aperture was 24.00 mm in females and 25.32 mm in males, the mean length was 32.54 mm in females and 36.35 mm in males. The difference between males and females was significant, and our data correlates well with the previously data acquired from humans skulls. Facial measurements also showed a statistically significant dimorphism. In morphometric geometrics, the correlation between the centroïd size and PC1 in the shape space was weak, while this correlation was strong in the size and shape space. Visualization of shape differences was achieved on 2D wireframes.

Conclusion

Shape and size analysis of the piriform aperture showed the existence of a significant sexual dimorphism. These results encourage us to go further with functional and imaging correlations.  相似文献   
998.

Introduction

Malnutrition is a negative predictive factor for survival in end stage renal disease (ESRD) patients. Coincidence of malnutrition, inflammation and atherosclerosis (MIA syndrome) in the dialysis population is an exceptionally poor outcome event. Due to flexibility, ease of performance and reproducibility, clinical scales are of particular value in assessment of nutritional status in ESRD patients. The aim of the present study was to evaluate the clinical value of Mini Nutritional Assessment (MNA) in peritoneal dialysis (PD) patients.

Material and methods

Nutritional status was assessed in 41 peritoneal dialysis patients by means of the MNA scale and malnutrition inflammation score (MIS). Some other clinical and laboratory parameters associated with nutritional status were analyzed. Patients were followed up for 30 months.

Results

In the analyzed group of patients a good nutritional state was diagnosed in 22 patients (54%), risk of malnutrition in 17 (41%) and malnutrition in 2 patients (5%) based on the MNA scale. A strong correlation between MNA based nutritional status and MIS was found (r = –0.85, p < 0.01, ANOVA, p < 0.01). Differences in time on dialysis, body mass index, concentration of albumin, cholesterol and triglycerides were noted between at risk/malnourished and well-nourished (according to MNA) patients. Statistically significant factors determining survival of patients by Cox proportional hazard analysis were age (HR 1.07), being at risk/malnourished according to MNA (HR 5.7), MIS (HR 1.2), and albumin (HR 0.13).

Conclusions

The MNA scale is a valuable, clinically suitable tool for assessment of nutritional status in peritoneal dialysis patients. Risk of malnutrition and malnutrition diagnosed by MNA identifies patients at high mortality risk.  相似文献   
999.
1000.

Introduction

Retinal thickness in primary open-angle glaucoma patients was determined to establish its correlation with advancement of glaucoma neuropathy.

Material and methods

One hundred ninety-four patients (371 eyes, age 30–65 years) were divided in 3 groups including 50 patients with confirmed primary open-angle glaucoma, 67 primary open-angle glaucoma-suspected patients and 77 healthy persons (control group). The retinal foveola, foveal, peri-foveal and posterior pole average thickness values were determined with an RTA analyzer. For comparison, linear cup-to-disc diameter ratio (C/D), nerve fiber index (NFI) and mean defect of the retina sensitivity (MD) were also determined.

Results

Statistically highly significant differences in the retinal thickness and glaucoma parameters between the individual groups were observed. In the peri-foveal region, the retinal thickness in glaucoma patients was only 173.0 ±11.4 µm while in the healthy patients 201.1 ±13.1 µm. In the posterior pole region, the thickness values were only 168.1 ±11.3 µm and 195.7 ±12.3 µm, respectively. A moderate correlation between retinal thickness in peri-foveal and posterior pole regions and the C/D, NFI and MD parameters was also established (Pearson coefficients below –0.351 or above 0.284).

Conclusions

The retinal thickness in the peri-foveal and posterior pole regions depends on the degree of glaucoma advancement. This original observation may be a basis for acceptance of this method as a quite new tool in glaucoma diagnosis.  相似文献   
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