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91.
There are no studies so far linking molecular regulation of lymphangiogenesis and induction of adaptive immunity. Here, we show that blockade of vascular endothelial growth factor receptor-3 (VEGFR-3) signaling significantly suppresses corneal antigen-presenting (dendritic) cell trafficking to draining lymph nodes, induction of delayed-type hypersensitivity and rejection of corneal transplants. Regulating the function of VEGFR-3 may therefore be a mechanism for modulating adaptive immunity in the periphery.  相似文献   
92.

Objective

To provide a low-cost and simple model of culturally-appropriate and low cost facilities for improvement of physical activity for girls and their mothers through an after-school program and to determine the changes in anthropometric indexes after this trial.

Methods

This national study was conducted in 2006-2007 in 7 provinces with different socioeconomic situations in Iran. Female students who studied in the 7th through 10th grade and their mothers were selected by random cluster sampling. In each province, 24 sessions of after-school aerobic physical activity were held for 90 minutes, two days a week, and 3 months long at school sites in the afternoon.

Findings

The study comprised 410 participants (204 mothers and 206 daughters), with a mean age of 15.86±1.01 and 40.71±6.3 years in girls and their mothers, respectively. The results of the focus group discussions showed that in general, both mothers and daughters were satisfied from the program and found it feasible and successful. After the trial, the indexes of generalized and abdominal obesity improved significantly both in girls and in their mothers (P-value <0.0001 for weight, body mass index and waist circumference).

Conclusion

Our findings may provide a low-cost and simple effective model of motivation for physical activity with targeted interventions for girls and their mothers. We suggest that the success of this trial might be a result of bonding and accompaniment of mothers and daughters. Such model can be integrated in the existing health and education systems to increase the physical activity level.  相似文献   
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Beckwith-Wiedemann syndrome is an overgrowth dis-order that predisposes to the development of a variety of malignancies including Wilms tumor. Pathologists may suspect the presence of Beckwith-Wiedemann syndrome, which may be clinically subtle, on the basis of the histopathology of the renal parenchyma adjacent to a Wilms tumor. These kidneys typically harbor multiple nephrogenic rests (especially perilobar nephrogenic rests), and their medullas have blunted papillae resulting from excessive fibromyxoid stroma, decreased collecting ducts, and decreased Henle loops. This complex of findings constitutes the so-called Beckwith Medulla. Extensions of this stroma-rich medulla into the cortex results in characteristic dysplastic medullary-ray nodules. Identification of these histologic abnormalities by the pathologist should prompt the clinician to evaluate the child for Beckwith-Wiedemann syndrome. Proper screening of these children can allow for early detection of cancers and treatment while these cancers are curable.  相似文献   
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Squamous cell carcinoma (SCC) is the second most common type of skin cancer with potential risks for metastasis and recurrence if left untreated or incompletely excised. This case series study was designed to determine the frequency of incompletely excised SCCs and the related risk factors. A total of 273 SCCs (253 patients) excised in Razi dermatology hospital of Tehran from 2006-2008, were evaluated and were analyzed by Chi-square or t-test. The incidence of incomplete excision was 17.58 % and deep margin involvement was observed in 73% of lesions. Risk factors associated with incomplete excision of SCCs were being female, location of the tumors (in particular the lesions on lateral canthus, upper lip, foot, forehead, cheek, neck, nose and ear), large lesions and grafting method of repair. There was no statistically significant difference for the age, degree of histological differentiation, childhood history of radiotherapy for tinea capitis and the type of anesthesia. More care should be taken for high risk SCCs as complete excision avoids potential risk of recurrence and metastasis.  相似文献   
98.
Benign smooth muscle tumors rarely occur in the head and neck and, to the best of our knowledge, have not been reported in the pterygopalatine fossa. In this report, we describe a 15-year-old adolescent who presented with facial pain and was found to have a large skull base tumor centered in the pterygopalatine fossa. The patient underwent an expanded endonasal endoscopic approach for complete resection of this lesion with resolution of his symptoms. Pathology revealed a well-differentiated smooth muscle neoplasm consistent with a leiomyoma. This case adds to the growing body of literature supporting a role for endoscopic procedures in the treatment of skull base pathologies in pediatric patients.  相似文献   
99.
People with attention-deficit/hyperactivity disorder (ADHD) often experience sleep problems, and these are frequently exacerbated by the methylphenidate they take to manage their ADHD symptoms. Many of the changes to sleep are consistent with a change in the underlying circadian clock. The present study was designed to determine if methylphenidate alone could alter properties of the circadian clock. Young male mice were examined in light-dark cycles and in constant darkness and recordings were performed on behavioral activity, sleep, and electrical activity in the suprachiasmatic nucleus (SCN) of freely moving mice. Methylphenidate in the drinking water (0.08%) significantly increased activity in the mid-to-late night, and led to a delay in the onset of activity and sleep relative to the light-dark cycle. While locomotor levels returned to baseline after treatment ended, the phase angle of entrainment required at least a week to return to baseline levels. In constant darkness, the free-running period of both wheel-running and general locomotor rhythms was lengthened by methylphenidate. When the treatment ended, the free-running period either remained stable or only partially reverted to baseline levels. Methylphenidate also altered the electrical firing rate rhythms in the SCN. It induced a delay in the trough of the rhythm, an increment in rhythm amplitude, and a reduction in rhythm variability. These observations suggest that methylphenidate alters the underlying circadian clock. The observed changes are consistent with clock alterations that would promote sleep-onset insomnia.  相似文献   
100.
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