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排序方式: 共有691条查询结果,搜索用时 15 毫秒
591.
SUMMARY The present study constitutes an attempt to compare normal traits for palatal height and width at different stages of dentition development of two ethnic groups of the Middle East. The observations were obtained from 346 randomly selected normal subjects, 188 Saudis and 158 Egyptians. The stone models were divided into three categories in both groups — primary, mixed and permanent dentitions. Palatal index values were calculated at two levels. Vernier calipers were used to measure the palatal width. Palatal depth was measured by profile Gauge by Vitrex. The results of this study demonstrate no significant difference between ethnic groups at levels 1 and 2 in relation to the palatal height, width and index. For both groups, palatal index increased significantly from the primary to mixed and permanent dentition at level 1.
At level 2, palatal index and height showed decreases in measurement in the mixed dentition compared with the primary and the permanent dentitions.
Subjective assessment of the palatal height correlated with palatal index. The casts were then labelled so that the shallow group had the smallest palatal index followed by the normal and the deep group had the largest palatal index. The results contribute to the information available on the development of palatal shape within two Middle Eastern populations. Knowledge of the normal range in shape can act as a baseline for studies of certain oral developmental abnormalities. 相似文献
At level 2, palatal index and height showed decreases in measurement in the mixed dentition compared with the primary and the permanent dentitions.
Subjective assessment of the palatal height correlated with palatal index. The casts were then labelled so that the shallow group had the smallest palatal index followed by the normal and the deep group had the largest palatal index. The results contribute to the information available on the development of palatal shape within two Middle Eastern populations. Knowledge of the normal range in shape can act as a baseline for studies of certain oral developmental abnormalities. 相似文献
592.
593.
594.
JEAN LUC REY FOUAD EL GHELBAZOURI CHRISTOPHE TRIBOUILLOY 《Pacing and clinical electrophysiology : PACE》1996,19(11):1777-1779
A new mode of biphasic pacing was used in 26 patients to assess the feasibility of atrial pacing by means of the floating atrial ring electrodes of a single lead VDD permanent pacing system. During implantation, atrial pacing was possible in 25 patients with a 1-ms total pulse duration, a mean atrial threshold of 1.70 ± 0.60 V (range, 0.6–3.0), and a mean diaphragmatic threshold of 6.7 ± 2.5 V (range, 2.5–10.0). At 3 months, the atrial threshold had increased beyond 4.8 V in three patients. In the 22 other patients, the mean atrial threshold was 2.2 ± 0.5 V (range, 1.50–3.50) in the supine position and 2.5 ± 0.8 V (range, 1.5–4.8) in the sitting position. Stable atrial capture without diaphragmatic stimulation was achieved in 76% of patients. 相似文献
595.
Gohagan JK; Spitznagel EL; Murphy WA; Vannier MW; Dixon WT; Gersell DJ; Rossnick SL; Totty WG; Destouet JM; Rickman DL 《Radiology》1987,163(3):703-707
Preliminary investigations were conducted into the potential of magnetic resonance (MR) images for tissue classification of the breast on the basis of relative signal intensity. Multispectral techniques originally developed by the National Aeronautics and Space Administration for satellite image analysis were used in sequence selection, image data correction, image standardization, and image interpretation. Numerous sequence combinations with varying repetition times (TR) and echo times (TE) were considered, and a triplet was selected consisting of long TR/long TE, short TR/short TE, and an opposed phase sequence with intermediate TR and TE. Correction to remove system-imposed intensity inhomogeneities was required for all images. Image standardization based on fat and pectoral muscle signals was necessary for intercase comparisons. Multispectral images obtained based on this analysis suggest the feasibility of intensity-based image classification. 相似文献
596.
On truth telling and the diagnosis of Alzheimer's disease 总被引:3,自引:0,他引:3
597.
An extract of the sycamore tree, known by the ancient Egyptians for its medicinal properties, was used to treat certain dermatoses in a group of Egyptian patients. Twenty-one patients having a variety of conditions including pityriasis alba, atopic dermatosis, psoriasis and tina infections were given a cream containing the active material. The response was excellent. 相似文献
598.
599.
Neural network analysis of ventilation-perfusion lung scans 总被引:1,自引:0,他引:1
600.
Background. Lupus miliaris disseminatus faciei is a chronic inflammatory disorder, which affects adults of both sexes. Methods. This study included 25 patients with lupus miliaris disseminatus faciei. Three biopsies, representing early, fully developed, and late lesions, were taken from each patient. Results. Histopathologic examination of the different lesions revealed that in early lesions, all of them showed superficial perivascular and periappendigeal cellular infiltrate composed mostly of lymphocytes and few histiocytes with occasional neutrophils. The fully developed lesions showed a sarcoidal granuloma only (40%), sarcoidal granuloma with abscess (24%), sarcoidal granuloma around areas of caseation necrosis (20%), and a mixture of sarcoidal and tuberculoid granulomas (16%). Conclusions. All the late lesions showed extensive fibrosis especially in the perifollicular areas. Scattered lymphocytes, histiocytes and neutrophils were present within the fibrotic areas. A possible explanation of the pathogenesis is discussed. 相似文献