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91.
Differentiated papillary thyroid carcinoma (D-PTC) is the most common malignancy arising in the thyroid gland. There are gender differences in the incidence of PTC being mainly observed in females. Low-risk groups consisted of men younger than 40-year-old and women younger than 50-year-old, whereas the high-risk group are older patients. We believe that age is not enough to explain the clinical course of this neoplasm and hypothesize that aggressive behavior of D-PTC may be correlated with hormonal status. Studies that support this idea showed that the follicular neoplastic cells had higher estrogen receptor-alpha in premenopausal (28.1+/-4.5) than in postmenopausal women (14.2+/-2.9). According to author's prior observations, there are evidences correlating recurrence of D-PTC with postmenopause in women. Postmenopause status is characterized by estrogen decrease and FSH increases both associated with EGFR activation. Previous observations identified EGFR over-expression in D-PTC of postmenopause when compared with premenopausal ladies. Conclusions: Postmenopause is an adverse factor for tumor evolution in women with D-PTC and is associated with EGFR expression. It's introduction in thyroid tumor stratification could be a fine tuning in predicting papillary thyroid carcinoma behavior. 相似文献
92.
Lucas JN Rudmann DG Credille KM Irizarry AR Peter A Snyder PW 《Toxicologic pathology》2007,35(2):199-207
The development and morphology of the rat mammary gland are dependent upon several hormones including estrogens, androgens, progesterone, growth hormone and prolactin. In toxicology studies, treatment with xenobiotics may alter these hormones resulting in changes in the morphology of reproductive tissues such as the mammary gland. In the rat, male and female mammary glands exhibit striking morphologic differences that can be altered secondary to hormonal perturbations. Recognizing these morphologic changes can help the pathologist predict potential xenobiotic-induced perturbations in the systemic hormonal milieu. This review examines the development of the rat mammary gland and the influence of sex hormones on the morphology of the adult male and female rat mammary gland. Specific case examples from the literature and data from our laboratory highlight the dynamic nature of the rat mammary gland in response to hormonal changes. 相似文献
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Callejón G Mayor-Olea A Jiménez AJ Gaitán MJ Palomares AR Martínez F Ruiz M Reyes-Engel A 《Human reproduction (Oxford, England)》2007,22(12):3249-3254
BACKGROUND Polymorphisms C677T and A1298C of the MTHFR gene have been implicated in fetal viability. In this study, we determined the allele and genotype frequencies of these polymorphisms in different populations, including spontaneous abortion (SA) fetal tissues, with the objective of evaluating their impact on fetal viability. METHODS 342 samples of fetal tissues, selected from SA occurring during the 1980s, 230 samples from subjects born in the 1980s and a third set of samples from 204 subjects born in the 1950s, were genotyped by using TaqMan probes. RESULTS The wild CC genotype of the C677T polymorphism showed a strong protective effect against abortion (0.03 in SA versus 0.47 in 1950s and 0.43 in 1980s) (P < 0.0001). Genotypes of three mutations in the combinations of polymorphisms for C677T and A1298C showed a very low frequency in the living population; however, the three mutations genotypes were over expressed in the SA group (0.02 in 1950s; 0.03 in 1980s and 0.17 in SA) (P < 0.0001). Samples with four mutations (n = 2) were found only in the SA group. CONCLUSIONS There is no linkage disequilibrium between C667T and A1298C polymorphisms. Fetal viability is directly related to the CC genotype as a protector while the three and four mutation MTHFR genotypes appear to be a determinant on fetal non-viability and SA. 相似文献
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Lopez-Ramirez Felipe Gushchin Vadim Sittig Michelle King Mary Caitlin Baron Ekaterina Nikiforchin Andrei Nieroda Carol Sardi Armando 《Annals of surgical oncology》2022,29(6):3404-3404
Annals of Surgical Oncology - 相似文献
97.
Nikiforchin Andrei Sittig Michelle Gushchin Vadim Sardi Armando 《Annals of surgical oncology》2022,29(2):883-884
Annals of Surgical Oncology - 相似文献
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