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81.
A case of mixed medullary follicular carcinoma of the thyroid is reported. Grossly, the tumor was a solid, grayish white, well circumscribed mass without lymph node metastasis. Microscopically, the tumor showed both medullary and follicular areas. The follicular areas occupied discrete portions of the tumor, and were considered to be neoplastic. Tumor cells in the medullary area were polyhedral or spindle-shaped. There was no amyloid deposition within the tumor. Immunohistochemically, tumor cells in the medullary area were positive for calcitonin and negative for thyroglobulin. Some cells lining the follicles were positive for thyroglobulin. By electron microscopy, two types of tumor cell were observed. One type contained numerous cytoplasmic secretory granules, whereas the other type had few granules and showed a prominent rough endoplasmic reticulum. These findings suggested that this mixed medullary follicular carcinoma of the thyroid presented neoplastic changes within a common cell lineage. 相似文献
82.
本文利用兔抗人TSH(hTSH)多克隆抗体、(125)~I-鼠抗hTSH单克隆抗体、固相驴抗兔二抗建立了液相高灵敏度人血清TSH免疫放射分析。方法学考核显示,灵敏度为0.008mIU/L,批内和批间变异系数分别为1.6%~4.1%和2.7%~8.6%,回收率为95.2%~101.4%,与hFSH和hHCG的交叉反应率分别为4.41×10~(-5)和5.08×10~(-7).用本法测定了34名正常人、27例甲亢和9例甲低患者血清值,结果与临床相符。 相似文献
83.
H. Tateyama Y. Yang T. Eimoto T. Tada H. Inagaki T. Nakamura H. Iwase S. Kobayashi 《Virchows Archiv : an international journal of pathology》1994,424(5):533-537
The expression of proliferative cell nuclear antigen (PCNA) in follicular tumours of the thyroid was examined by immunohistochemistry. Both usual nonoxyphilic cell follicular tumours (non-OCT) and oxyphilic cell tumours (OCT) were subdivided into benign, indeterminate, encapsulated carcinoma, and widely invasive carcinoma types. Among non-OCT the percentages of PCNA-positive cells in benign tumours, encapsulated carcinomas, and widely invasive carcinomas was 2.5%–8.6%, 11.8%–39.1%, and 18.6%–20.0%, respectively. There was a statistically significant difference between benign tumours and encapsulated or widely invasive carcinomas, as in previous studies. A value of 10% was appropriate to distinguish benign from malignant lesions. PCNA-positive cells in indeterminate-type non-OCT were not significantly different from those in benign tumours, ranging from 4.3%–19.6%, and occurring at more than 10% in three of six tuours. Among OCT the positivity was less than 10% in benign tumours (4.5%–7.8%) and more than 10% in malignant tumours (14.1%–35.9%) and all the eight indeterminate tumours (12.5%–27.3%), with a statistically significant differences between the benign tumour and each of the latter types. These results indicate that the examination of PCNA is valuable in diagnosis of thyroid follicular tumours and that the use of similar diagnostic criteria may be warranted in both non-OCT and OCT. 相似文献
84.
Hosal SA Apel RL Freeman JL Azadian A Rosen IB LiVolsi VA Asa SL 《Endocrine pathology》1997,8(1):21-28
Molecular analyses of thyroid tumors have documented mutations in the tumor suppressor p53 gene almost exclusively in anaplastic
carcinomas. In contrast, immunohistochemistry has localized p53 in differentiated papillary and follicular thyroid cancers.
To establish the significance of p53 immunolocalization in these lesions, 78 thyroid tumors of follicular derivation were
examined. All tumors were classified by strict criteria and the extent of tumor was determined morphologically. Immunohistochemical
staining for p53 was performed on paraffin sections of formalin-fixed tumor tissue. The results of staining were correlated
with diagnosis, tumor extent and clinical outcome. Immunopositivity for p53 was diffuse and strong in all five anaplastic
carcinomas examined. There was no staining in five of six follicular adenomas. Four of nine follicular carcinomas had some
degree of nuclear staining, but this was focal; all nine tumors were confined to the thyroid at the time of examination. Of
49 papillary carcinomas, 26 were intrathyroidal, and 7 of these were occult; there was no p53 positivity in any occult lesion
and only 5 of the 19 palpable lesions stained. In contrast, among 23 papillary carcinomas with extrathyroidal extension or
metastases, only 9 were negative for p53 immunoreactivity. Five of seven tall cell papillary carcinomas and one of two insular
carcinomas had p53 immunopositivity and this correlated with aggressive behavior. These results support the tumorigenic role
of p53 mutations postulated for anaplastic thyroid carcinomas and indicate that localization of p53 by immunohistochemistry
is a useful prognostic index of clinical behavior in differentiated thyroid carcinomas of follicular cell derivation. 相似文献
85.
The role of intraoperative frozen section in certain organ systems such as the thyroid continues to be problematic. In many
cases, diagnoses are deferred or nonhelpful—“follicular lesion.” In the modern era, the widespread use of preoperative aspiration
biopsy has allowed for more careful selection of patients who undergo thyroid surgery. In many cases, the fine-needle-aspiration
(FNA) biopsy diagnosis can be definitive or can guide the specific surgical procedure. The literature supports our approach,
which is summarized as follows: Intraoperative consultation is not needed on the intrathyroidal nodule if a preoperative FNA
was definitive for papillary carcinoma. Frozen section is of no value in the intraoperative diagnosis of lesions diagnosed
on FNA as “follicular neoplasm” or “Hürthle cell neoplasm” because the characterization of these lesions requires detailed
analysis of the tumor capsule for the demonstration of capsular and/or vascular invasion—an analysis that is not practical
in the intraoperative setting. Finally, intraoperative consultation including frozen section and intraoperative cytologic
examination is most useful in those cases that are diagnosed as suspicious for papillary carcinoma by FNA, because the assessment
of nuclear features needed for the definitive diagnosis is possible with intraoperative techniques in a significant number
of cases. 相似文献
86.
D.V. Coscina J.W. Chambers I. Park S. Hogan J. Himms-Hagen 《Brain research bulletin》1985,14(6):585-593
Two experiments were performed to determine if bilateral parasagittal hypothalamic knife-cuts (KCs), which produce long-term overeating and obesity, after biochemical indices of brown adipose tissue (BAT) reactivity to thermogenic stimuli. In the first study, responses to environmental cold were tested. Four weeks after surgery, KC rats had gained 4-5 times more weight than controls and were obese (increased Lee Obesity Index and weight of gonadal white fat). Before being sacrificed, groups of KC and control rats were exposed to 4 degrees C for 21 hr or remained at 28 degrees C. Interscapular BAT weighed 300% more in KC rats, due largely to increased white fat content. Functional indices of BAT thermogenic capacity (protein content, DNA content, cytochrome oxidase activity and mitochondrial guanosine diphosphate (GDP) binding) were normal at 28 degrees C. Exposure to 4 degrees C produced greatly enhanced responses but these were equivalent for both groups. This suggested an intact capacity for non-shivering thermogenesis in obese KC rats. In the second study, the same BAT responses were examined in other rats fed a palatable "cafeteria" diet (CAFE). One week after surgery, KC and control rats were subdivided into groups that received chow alone or chow plus four different palatable foods daily. Before sacrificing 4-5 weeks later, KC rats had gained 3-4 times more weight than controls and were obese. Interscapular BAT weighed 200-300% more in KC rats. CAFE feeding produced larger increments in all variables for KC vs. control rats. Most importantly, GDP binding was reduced in both KC groups, and significantly more so after CAFE feeding.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
87.
目的 了解重庆地区健康体检人群中成年女性的甲状腺结节(thyroid nodules,TNs)检出情况及影响因素,为甲状腺疾病的防治提供参考。方法 分析重庆某大型三甲医院健康体检中心38 069例健康女性体检者甲状腺超声检查情况及代谢相关指标,计算甲状腺结节的检出率并分析其影响因素。结果 38 069例健康女性体检者中,16 042例检出甲状腺结节,检出率为42.1%,多发性甲状腺结节8 908例,占比为55.5%,甲状腺结节的检出率随年龄增长而增加(P<0.01)。多因素logistic 回归分析提示,年龄增加(>30岁)、中心性肥胖(OR=1.16,95%CI:1.08~1.25)、高血压(OR=1.16,95%CI: 1.07~1.25)是甲状腺结节的独立危险因素(P<0.01); 低BMI是甲状腺结节的保护因素(OR=0.89,95%CI: 0.81~0.98, P<0.01)。结论 重庆地区女性甲状腺结节检出率较高,对于高龄、中心型肥胖及高血压女性人群应该重点进行甲状腺结节的超声筛查,以便早期发现和诊断。 相似文献
88.
目的:探讨超声联合血清甲状腺过氧化物酶抗体(TPO–Ab)、甲状腺球蛋白抗体(Tg–Ab)评价桥本甲状腺炎(HT)临床进程的应用价值。方法:选择2021年9月至2022年8月贵州航天医院接诊的HT患者100例纳入观察组,另选择同期于贵州航天医院体检的健康者100例纳入对照组,两组研究对象均行彩色多普勒超声及血清TPO–Ab、Tg–Ab检查。比较两组研究对象血清TPO–Ab与Tg–Ab水平,并分析观察组患者术后病理或空心针穿刺活检组织病理学分级情况,以及观察组患者不同术后组织病理学分级患者血清TPO–Ab与Tg–Ab水平。以术后病理或空心针穿刺活检组织病理学分级为标准,评价超声、血清TPO–Ab与Tg–Ab单独及联合检测对观察组患者组织病理学分级的诊断准确度。结果:观察组患者血清TPO–Ab及Tg–Ab水平均高于对照组健康者,差异具有统计学意义(P <0.05)。观察组中,组织病理学分级为Ⅰ级的患者有58例,Ⅱ级有30例,Ⅲ级有12例;Ⅰ级患者血清TPO–Ab与Tg–Ab水平均低于Ⅱ、Ⅲ级患者,Ⅱ级患者血清TPO–Ab与Tg–Ab水平均低于Ⅲ级患者,差异均具有统计学意义(P <... 相似文献
89.
Yoonyoung Jang Yoon-Jung Choi Youn-Hee Lim Kyung-Shin Lee Bung-Nyun Kim Choong Ho Shin Young Ah Lee Johanna Inhyang Kim Yun-Chul Hong 《Yebang Ŭihakhoe chi》2021,54(1):37
ObjectivesBisphenol A (BPA) is used in the electrical, mechanical, medical, and food industries. Previous studies have suggested that BPA is an endocrine disruptor. Regulation of BPA has led to increased use of bisphenol F (BPF) and bisphenol S (BPS). However, few studies have investigated the associations of BPF and BPS with thyroid dysfunction in children. Our study investigated the associations of prenatal BPA and early childhood BPA, BPF, and BPS exposure with thyroid function in 6-year-old children.MethodsPrenatal BPA concentrations were measured during the second trimester of pregnancy in an established prospective birth cohort. We measured urinary BPA, BPF, and BPS concentrations and thyroid hormone levels (thyroid-stimulating hormone, total T3, and free T4) in 6-year-old children (n=574). We examined the associations between urinary bisphenol concentrations and percentage change of thyroid hormone concentrations using multivariate linear regression. We also compared thyroid hormone levels by dividing the cohort according to BPA, BPF, and BPS concentrations.ResultsThe associations between prenatal BPA and total T3 levels were statistically significant in all models, except for girls when using a crude model. The associations between urinary BPA and BPS concentrations and levels of all thyroid hormones were not statistically significant. However, we observed that lower free T4 levels (−1.94%; 95% confidence interval, −3.82 to −0.03) were associated with higher urinary BPF concentrations in girls only.ConclusionsOur findings identified significant associations between prenatal BPA exposure and total T3 levels in all children and between BPF exposure and free T4 levels in girls only. 相似文献
90.
目的探究肺结节特点与其病理结果的相关性,分析患者临床特征(临床因素、检验结果、胸部CT影像特征)对判断肺结节良恶性的临床意义。 方法回顾性分析147例肺结节患者,根据病理活检结果分为良性组39例,恶性组108例。比较两组患者的一般情况(性别、年龄、吸烟史、恶性肿瘤家族史)、肺癌4项[癌胚抗原(CEA)、鳞状上皮细胞抗原(SCCAg)、神经元特异性烯醇化酶(NSE)、细胞角蛋白19片段(Cyfra21-1)]以及高分辨率CT征象,评估差异有统计学意义的因素在鉴别良恶性肺结节中的效能。 结果两组患者在性别、吸烟史、4个肺癌指标(CEA、SCCAg、NSE、Cyfra21-1)、结节大小、结节边缘、毛刺征的比较,差异均无统计学意义(均P>0.05),在年龄、恶性肿瘤家族史、结节形态、分叶征、空泡征、胸膜牵拉征、血管集束征的比较,差异均有统计学意义(均P<0.05)。在高分辨率CT征象中,分叶征对判断肺结节良恶性的效能最高,敏感度达79.6%。Logistic线性回归分析显示磨玻璃结节、分叶征、空泡征都是恶性的危险因素(均P<0.05)。 结论患者的年龄、恶性肿瘤家族史、结节形态(磨玻璃结节)、分叶征、空泡征、胸膜牵拉征、血管集束征对鉴别肺结节良恶性有一定的参考意义。 相似文献