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1.
目的 :观察血清保存方法对促甲状腺激素 (TSH)结果的影响。方法 :将甲状腺功能正常、异常患者共 10份血清 ,采用不同血清量、不同条件分组保存后测定 TSH。结果 :保存方法对 TSH结果有一定的影响。结论 :用于 TSH血清的保存量要多、要密封管口、低温保存。  相似文献   
2.
生长抑素受体显像近年来研究较多,depreotide已成为其研究热点之一。Depreotide在诊断与鉴别诊断临床常见的孤立性肺结节方面有其独特优势;此外,^99mTc—depreotide生长抑素受体显像在乳腺癌、甲状腺癌、淋巴瘤等肿瘤及甲状腺相关性眼病等非肿瘤性疾病也有一定应用前景。  相似文献   
3.
This surgical anatomy study aimed to evaluate the possibility of identifying the external laryngeal nerve during thyroid surgery and the possible variations of nerves at risk. Fifty patients underwent total thyroidectomies during a period of 12 months. Using a neurostimulator, the distal motor branch of the external laryngeal nerve was searched. Electrical stimulation of a nervous branch aimed to provoke a global contraction of the cricothyroid in order to identify with certitude the external laryngeal nerve. The external laryngeal nerve was identified in 20% of cases. Its course was, with almost equal frequency, either (1) between the vessels of the superior thyroid pedicle or (2) superficial and anterior to the fascia of the cricothyroid muscle. The external laryngeal nerve is hard to find during thyroid surgery, even with a neurostimulator. It can be vulnerable during thyroid surgery but only in cases of anatomic variations. Searching for the nerve systematically during thyroid surgery does not seem to be useful. Several precautions when dissecting the superior pole of the thyroid gland seem to be necessary and sufficient to respect the external laryngeal nerve.  相似文献   
4.
The objective was to investigate glucose-6-phosphate dehydrogenase (G6PD) activity in monolayer cultures of thyroid epithelial cells and to examine whether inhibition of nitric oxide synthase affects activity of G6PD or oxygen sensitivity of the assay. Primary cultures without TSH addition prior to experiments demonstrated a TSH-dependent increase in G6PD activity. G6PD activity was higher in F12 medium than in a serum-free physiological medium. Secondary cultures grown in F12 medium demonstrated a diminished activity of G6PD and a lack of response to TSH. In the serum-free physiological medium, G6PD activity was comparable to that found in primary cultures and a response to high concentrations of TSH was maintained. In primary cultures grown in F12 medium devoid of TSH, G6PD activity decreased dose-dependently when nitric oxide synthase activity was inhibited. The oxygen sensitivity of the assay was comparable to that reported previously in malignant cells and correlated with the activity of G6PD in primary cultures. We suggest that thyroid epithelial cells may be an appropriate system to investigate oxygen sensitivity of the G6PD assay as the cells demonstrate a reduced oxygen sensitivity which can be influenced by culture conditions.  相似文献   
5.
A case of primary plasmacytoma of the thyroid gland which occurred in a 63-year-old woman is reported. Histologic and ultramicroscopic examination revealed that the excised thyroid tumor was plasmacytoma superimposed on lymphocytic thyroiditis. Immunohistological study showed that the tumor cells produced intracytoplasmic immunoglobulin (IgG-kappa). Electropho-retic and immunoelectrophoretic studies disclosed the presence of monoclonal immunoglobulin (IgG-kappa) in samples of the patient's serum which had been obtained preoperatively. After completion of irradiation therapy to the neck following tumor removal, the serum monoclonal immunoglobulin disappeared. The patient is currently alive and well without any evidence of the tumor three years after surgery.  相似文献   
6.
Geographic or ethnic differences in the incidence of thyroid carcinoma, as well as in the histologic distribution of thyroid carcinoma between Japan and Western countries, have been described but are still unclear. The recent establishment of histologic criteria for the diagnosis of thyroid carcinoma by the WHO committee has facilitated the comparison of clinicopathological data of patients with thyroid carcinoma all over the world. The aim of the present review article is to clarify the epidemiological and clinicopathological differences of thyroid carcinoma between Japan and Western countries. We found recently no significant differences in the incidence, mortality, and histologic distribution of thyroid carcinoma between Japan and Western countries; this was contrary to our expectation. This is likely attributable to westernization of the Japanese diet, standardized medical levels, and international standardization of histologic criteria of thyroid carcinoma.  相似文献   
7.
This study assessed the morphological criteria for the diagnosis of various types of lymphocytic thyroiditis in fine-needle aspirates. Of 950 aspirates, 121 revealed lymphocytic thyroiditis, including Hashimoto's thyroiditis (partly confirmed by serological or histological examination) and focal thyroiditis adjacent to neoplasms. The diagnosis of Hashimoto's thyroiditis was easy when the aspirated material was adequate and contained oxyphilic cells; in the fibrous type, diagnosis was rather difficult. Focal thyroiditis may be confused with Hashimoto's thyroiditis, especially when adjacent to neoplasm. Surgical exploration should be performed in cases of severe lymphocytic thyroiditis revealed by fine-needle aspiration with repeatedly negative antibody titers in order to exclude neoplasm.  相似文献   
8.
Papillary carcinomas (PCs) of thyroid are among the most common but least aggressive human malignancies. The factors explaining the indolence of these tumors are unknown but host-tumor immune interactions may play a role. This study was designed to determine if there is morphologic evidence of these. Frozen tissues collected from 21 PCs, 4 follicular adenomas (FAs), 4 follicular carcinomas (FCs), and 11 nodular hyperplasias (NHs) were stained immunohistochemically for HLA-D antigens, lymphocyte and macrophage markers; results were graded numerically. Paraffin-embedded tumors (35 PCs, 10 FAs, and 10 FCs) were stained for S-100 protein to detect Langerhans' cells (LCs). Diffuse staining for HLA-D antigens and heavy mononuclear infiltrates were found more commonly in PCs compared to follicular neoplasms (FNs) or NHs. No consistent relationship was found between lymphocyte/macrophage infiltrates and expression of HLA-D antigens. The largest number of LCs was in PCs (median 11.8 cells/standard microscopic field [c/smf]), fewer cells were found in FA (3.7 c/smf), and the least in FC (0.05 c/smf). Features of host-tumor interaction including HLA-D expression and infiltrates with lymphocyte macrophages and LC are more strongly expressed in PC than other tumors. This may play a role in explaining their biological behavior.  相似文献   
9.
Previous results in experimental systems have suggested that hydroxylated PCBs may decrease thyroid hormone levels through associative interaction with transthyretin. In the present paper it was investigated whether this property was also shared by various industrial chemicals, mainly pesticides. In total, 65 compounds from 12 chemical groups were analyzed for direct interference with the T4 binding site of transthyretin using a competitive binding assay. Sixty per cent of the compounds were competitive at a concentration level of 100 M. Relatively strong interactions were observed by several chlorophenols, chlorophenoxy acids and nitrophenols, as well as by individual compounds such as hexachlorobenzene, dicofol, bromoxynil and tetrachlorohydroquinone. Examples from these chemical groups, e.g. pentachlorophenol, 2,4-dichlorophenoxybutyric acid, dinoseb and bromoxynil, also reduced plasma TT4 levels in rats. In addition, bromoxynil decreased plasma TT3 levels. The results suggest the existence of a number of halogenated industrial chemicals with a potential for lowering plasma thyroid hormone levels through interference with hormone transport carriers.  相似文献   
10.
Hypothyroidism developed in a neonate following the excision of a large cervical teratoma. This finding supports the observation that cervical teratomas commonly arise from thyroid tissue. Thyroid function tests should be performed routinely in all patients in whom identifiable residual thyroid tissue is not demonstrated at the conclusion of the operation. Accepted: 19 December 1997  相似文献   
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