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991.
Background:  Oral leukoplakia (OL) is the main potentially malignant lesion of the oral cavity, and oral squamous cell carcinoma (OSCC) accounts for more than 95% of all malignant neoplasms in the oral cavity. Therefore, the aim of this study was to verify the immunoexpression of p-Akt and Metallothionein (MT) proteins in dysplasic and neoplasic oral lesions.
Methods:  Immunohistochemical studies were carried out on 10 normal epithelium, 30 OL and 15 OSCC paraffin-embedded samples. Immunoperoxidase reaction for p-Akt and MT proteins was applied on the specimens, and the positivity of the reactions was calculated for 1000 epithelial cells.
Results:  Using the ANOVA and the Tukey's post hoc statistical analyses, it was observed a significant difference in the immunoexpression for p-Akt and MT when the OSCC samples were compared with normal and dysplasic epithelial groups. In addition, the Pearson's correlation test showed a significant correlation between the proteins' expression.
Conclusion:  Based on the data obtained, p-Akt and MT activation may play an important role in the conversion of a potentially malignant oral lesion to a malignant carcinoma since its earlier stages.  相似文献   
992.
The aim of this study was to estimate the 1-year prevalence of migraine and the degree of the association of migraine with some sociodemographic characteristics of a representative sample of the adult population of Brazil. This was a cross-sectional, population-based study. Telephone interviews were conducted on 3848 people, aged 18–79 years, randomly selected from the 27 States of Brazil. The estimated 1-year gender- and age-adjusted prevalence of migraine was 15.2%. Migraine was 2.2 times more prevalent in women, 1.5 times more in subjects with > 11 years of education, 1.59 times more in subjects with income of < 5 Brazilian Minimum Wages per month, and 1.43 times more in those who do not do any physical exercise. The overall prevalence of migraine in Brazil is 15.2%. Migraine is significantly more prevalent in women, subjects with higher education, with lower income, and those who do not exercise regularly, independently of their body mass index.  相似文献   
993.
Our aim was to determine whether histological changes occur in the cutaneous portion of pectoralis major flaps employed for upper aero-digestive tract reconstruction and, if present, to characterize these changes and try to infer their cause. Seven patients submitted to repair of aero-digestive tract defects secondary to cancer resection with pectoralis major myocutaneous flap were included in this study. All patients received adjuvant radiotherapy. Biopsies were taken from: the cutaneous portion of the flap; buccal mucosa; irradiated neck skin and chest skin opposite the donor site. Histological changes toward a “mucosalization” occur in the cutaneous portion of the pectoralis major flaps, characterized by disappearance of the horny layer or a reduction of its thickness and a decrease of the amount of cutaneous appendages. These changes are probably a result of continuous exposure to the intraoral environment in association with radiotherapy effects and may represent an advantageous adaptation for the patient.  相似文献   
994.
The International Journal of Cardiovascular Imaging - In theory, radiographic myocardial perfusion imaging allows a quantitative assessment of the functional significance of a coronary stenosis....  相似文献   
995.
Several synthetic, semi-synthetic and natural compounds as well as plant extracts were screened for their growth inhibition activity on KB cells. The most active ones were naphthoquinones and derivatives of pyrido [4,3-b]carbazole alkaloids, with inhibition dose (ID50) less than 4 micrograms/ml. Of the crude extracts of several plants screened, Vellozia caput-ardeae showed to be the most active.  相似文献   
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The penetration of ceftazidime into bone was determined by measuring the volume of distribution of 14C-ceftazidime in infected and non-infected bone of adult mongrel dogs. The volume of distribution in non-infected cortical bone was 0.114 +/- 0.011 l/kg (mean +/- S.E.M.) and increased significantly in non-infected immature callus to 0.484 +/- 0.13 l/kg (P less than 0.05). In the presence of infection, the volume of distribution in non-infected cortical bone was 0.144 +/- 0.05 l/kg, and significantly higher in infected reactive cortical bone, 0.453 +/- 0.07 (P less than 0.05). We conclude that ceftazidime penetrates infected and non-infected bone and that this penetration is greater into immature bone.  相似文献   
999.
穆莉  綦聚鳌  张清德 《药学学报》1992,27(5):336-344
用三种麻黄碱和芳醛反应合成28个2-芳基-3,4-二甲基-5-苯基噁唑烷类和Schiff碱类化合物。根据前药原理用UV和HPLC法探讨了立体结构和水解动力学的问题,测得生理条件下的水解半寿期,初步阐明了空间效应对稳定性的影响以及Hammett取代基常数与水解速率的规律。实验表明此类噁唑烷衍生物作为麻黄碱的前药有理论和应用价值。  相似文献   
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