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OBJECTIVE: To examine the applicability of the Tanaka and Johnston method of prediction in a Jordanian population and to develop a new prediction method for this specific population if necessary. MATERIALS AND METHODS: Three-hundred and sixty-seven Jordanians (193 female, 174 male, mean age 15.5 years) were randomly selected to represent 0.1% of 10th grade schoolchildren from Amman, Jordan. The mesiodistal crown diameters of the permanent teeth were measured and compared with the predicted values derived from the Tanaka and Johnston equations. RESULTS: Significant sexual dimorphism was found in tooth sizes. The correlation coefficients between the total mesiodistal width of the mandibular permanent incisors and that of the maxillary and mandibular canines and premolars were found to be 0.60 and 0.66, respectively. There were significant differences between the actual measurements and measurements derived from the Tanaka and Johnston equations. New linear regression equations were derived for both genders to allow tooth size prediction in Jordanians. CONCLUSIONS: There is a limitation in the application of the Tanaka and Johnston's prediction method to a Jordanian population. It is important to use separate equations for male and female patients.  相似文献   
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Objective

To determine whether commissural and projection fibers fractional anisotropy (FA) abnormalities can help in the prediction of long-term outcome of motor power affection after moderately severe traumatic brain injury (TBI).

Methods

MRI protocol included diffusion tensor imaging (DTI) and was performed for 32 patients with moderate TBI and 32 matched control subjects. Regions of interests were applied in the FA maps in the corpus callosum, internal capsules posterior limb, and cerebral peduncles. Results were compared in patients with motor power affection and patients without motor power affection to the control group.

Results

All patients had FA values lower than the control group with significance differences in the corpus callosum. Patient group with weakness had FA values lower than the control groups with significance differences in the posterior limb of the left internal capsules (p = 0.001) and left cerebral peduncles (p < 0.001). Significant differences were found when comparing the posterior limb of the left internal capsule (p = 0.002) and left cerebral peduncle (p = 0.022) to the right side in the weakness group.

Conclusion

FA values measured in the acute stage provided information about associated and projectional fibers disruptions, which have a prognostic value about motor power affection.  相似文献   
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Colon is a very rare site of metastasis from breast cancer. Its diagnosis is challenging. We report a new case of 56-year-old woman who was previously treated for lobular breast carcinoma 11 years ago. Radiologic features on barium enema and computed tomography (CT) were concordant with primary cancer of the transverse colon. The true diagnosis was made by immunohistochemical study of hemicolectomy specimen, which showed positivity for CA 15-3, cytokeratin 7, estrogen receptor, and progesterone receptor and negativity for cytokeratin 20 and carcinoembryonic antigen (CEA). The patient received chemotherapy and hormonal therapy. After a follow-up of 17 months, she is still alive with no evidence of recurrence. Literature review revealed that diagnosis should be suspected in the presence of bowel disorders in women with history of breast cancer even several years later. Surgery is beneficial in only isolated colonic metastasis. Otherwise, the treatment is based on systemic therapy. The prognosis is usually poor.  相似文献   
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T‐cell‐based immunological memory has the potential to provide the host with life‐long protection against pathogen reexposure and thus offers tremendous promise for the design of vaccines targeting chronic infections or cancer. In order to exploit this potential in the design of new vaccines, it is necessary to understand how and when memory T cells acquire their poised effector potential, and moreover, how they maintain these properties during homeostatic proliferation. To gain insight into the persistent nature of memory T‐cell functions, investigators have turned their attention to epigenetic mechanisms. Recent efforts have revealed that many of the properties acquired among memory T cells are coupled to stable changes in DNA methylation and histone modifications. Furthermore, it has recently been reported that the delineating features among memory T cells subsets are also linked to distinct epigenetic events, such as permissive and repressive histone modifications and DNA methylation programs, providing exciting new hypotheses regarding their cellular ancestry. Here, we review recent studies focused on epigenetic programs acquired during effector and memory T‐cell differentiation and discuss how these data may shed new light on the developmental path for generating long‐lived CD8+ T‐cell memory.  相似文献   
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