Diagnostic Use of Ultrasonography in Patients with Nodular Thyroid Disease

ObjectiveTo review the published reports pertaining to the diagnostic utility of ultrasonography for evaluation of thyroid nodules.MethodsVarious roles for diagnostic thyroid ultrasonography and screening ultrasound studies of the thyroid are discussed, and ultrasound characteristics of thyroid nodules and their association with malignant potential are described.ResultsIn two studies that correlated ultrasound findings with physical examination findings in patients with a solitary thyroid nodule detected by palpation, 16% of such patients had no corresponding nodule evident on ultrasonography, and 45% of such patients had an additional nodule detected by ultrasonography. Similarly, approximately 18% of patients with a palpable multinodular thyroid had no nodules larger than 1 cm in diameter on ultrasound studies. Thyroid nodules larger than 1 cm have been found by ultrasonography to be present in from 2 to almost 5% of the population with normal findings on examination of the thyroid. Use of screening ultrasound study of the thyroid has been suggested for patients with a history of childhood irradiation to the head and neck or a family history of thyroid cancer. Numerous investigations that have evaluated ultrasound features of thyroid nodules have suggested five characteristics as suggestive of malignant potential—hypoechogenicity, microcalcifications. irregular or microlobulated border, absent or irregular thick halo, and increased intranodular vascularity.ConclusionCorrelation of ultrasound and palpation findings will provide a comprehensive evaluation of nodular thyroid disease. Moreover, real-time ultrasonography facilitates characterization of features associated with an increased risk of a malignant lesion. High-resolution thyroid ultrasonography is a dynamic tool for endocrinologists. (Endocr Pract. 2004;10:246-252)     

Thyroid Nodules Detected by Contrast-Enhanced Magnetic Resonance Angiography: Prevalence and Clinical Significance

Background and Purpose

Incidental thyroid lesions are frequently found on contrast-enhanced magnetic resonance (CE-MR) angiography. The purpose of this study is to determine the prevalence of thyroid incidentalomas detected by CE-MR angiography and to evaluate their clinical significance by correlation with ultrasound (US) and cytopathological results.

Materials and Methods

We retrospectively reviewed 3,299 consecutive CE-MR angiography examinations performed at our institution between January 2010 and March 2013. Two radiologists evaluated the CE-MR angiography imaging in consensus regarding the presence, location, and vascularity of thyroid incidentaloma. We correlated these findings with follow-up US and cytopathologic results.

Results

The prevalence of thyroid incidentalomas detected by CE-MR angiography was 4.6% (152/3,299 patients). CE-MR angiography showed hypervascularity in 86.8% (145/167), isovascularity in 8.4% (14/167), and hypovascularity in 4.8% (8/167) of thyroid nodules compared to vascularity of thyroid parenchyma. Among the patients with thyroid incidentaloma, 34 patients (22.4%) were followed by US examination, and all 36 nodules on CE-MR angiography were detected on follow-up US. Of these nodules, 9 (25%) nodules were classified as probably benign, 26 (72.2%) as indeterminate, and 1 (2.8%) as suspicious malignant nodule. Among the 16 nodules with available cytopathologic results, 12 nodules were benign, 2 nodules were follicular neoplasm, and 2 nodules showed non-diagnostic results.

Conclusion

Incidental thyroid nodules were found in 4.6% of CE-MR angiography examinations. Because the high incidence of indeterminate US feature among thyroid incidentaloma, when a thyroid incidentaloma is detected on CE-MR angiography, further evaluation with US should be performed.     

Development of an imaging device for label-free parathyroid gland identification and vascularity assessment

During thyroid surgeries, it is important for surgeons to accurately identify healthy parathyroid glands and assess their vascularity to preserve their function postoperatively, thus preventing hypoparathyroidism and hypocalcemia. Near infrared autofluorescence detection enables parathyroid identification, while laser speckle contrast imaging allows assessment of parathyroid vascularity. Here, we present an imaging system combining the two techniques to perform both functions, simultaneously and label-free. An algorithm to automate the segmentation of a parathyroid gland in the fluorescence image to determine its average speckle contrast is also presented, reducing a barrier to clinical translation. Results from imaging ex vivo tissue samples show that the algorithm is equivalent to manual segmentation. Intraoperative images from representative procedures are presented showing successful implementation of the device to identify and assess vascularity of healthy and diseased parathyroid glands.     

Assessment of vascularity in histological sections: effects of methodology and value as an index of angiogenesis in breast tumours

The aims of this study were to (a) determine how the quantification of blood vessels in histological sections (vascularity) is affected by the methodology used and (b) assess the value of vascularity as an index of angiogenesis by comparing tumour and normal breast tissue. Archival specimens of breast, lung and oral carcinoma, oral dysplasia and normal breast tissue were used to test the effects of the following experimental variables on vascularity: pretreatment of the sections (enzymatic digestion, heating), endothelial markers (von Willebrand factor and CD31 antibodies), method of quantification (highest microvascular density, average microvascular density and microvascular volume) and interobserver variations. All the variables examined significantly affected the estimated vascularity; this depended on the type of tissue and method used. The pretreatment of the sections before staining was the most important variable, altering the vascularity ranking of the tumours. Vascularity in breast tumours was similar to that of the normal breast intralobular stroma, suggesting that an area of high microvascular density in the tumour does not necessarily represent tumour-induced angiogenesis. Contradictory results have been published regarding the value of vascularity as a tumour prognostic factor. Our results suggest that statistically significant differences in vascularity values are most likely to arise from failure to optimize the staining protocol and from the method used to assess vascularity. © 1998 Chapman & Hall     

Sonographic Appearance of Primary Thyroid Lymphoma-Preliminary Experience

Objective

Primary thyroid lymphoma (PTL) is an uncommon thyroid malignancy. Despite the rarity of PTL, it is important to recognize PTL promptly because its management differs from that of all the other thyroid neoplasms. This study was designed to investigate the sonographic features of PTL.

Methods

Twenty-seven pathologically confirmed PTLs were categorized into diffuse and non-diffuse type. Sonographic features including thyroid size, thyroid background echotexture, lesion size, echogenecity, calcification, vascularity, cervical lymphadenopathy of each type were retrospectively analyzed.

Results

All 27 PTLs were diffuse large B-cell lymphomas and were accompanied by diffuse Hashimoto''s thyroiditis. Ten were diffuse type and seventeen were non-diffuse type sonographically. The observations in diffuse group included goiter (10/10, 100.0%), marked echogenesity (10/10, 100.0%), heterogeneous echotexture (10/10, 100.0%), and cervical lymphadenopathy (4/10, 40.0%). The observations in non-diffuse group included marked hypoechogenicity (17/17, 100.0%), heterogeneous background thyroid gland (17/17, 100.0%), goiter (15/17, 88.2%), increased vascularity (8/13, 61.5%), mulifocality (10/17, 58.8%), and cervical lymphadenopathy (7/17, 41.2%).

Conclusions

Although some common features were found, the sonographic appearance of PTL is unspecific, especially for the diffuse type. Therefore, interventional diagnostic procedures should be warranted in the clinical settings when PTL is suspected.     

Characterization of hog thyroid peroxidase

Several fundamental properties of purified hog thyroid peroxidase (A413 nm/A280 nm = 0.55) were investigated in comparison with bovine lactoperoxidase. The Mr of thyroid peroxidase was 71,000. The prosthetic group of thyroid peroxidase was identified spectrophotometrically as protoheme IX after the enzyme was hydrolyzed with Pronase. Optical spectra of oxidized and reduced thyroid peroxidases and their complexes with azide and cyanide were very similar to lactoperoxidase, except that lactoperoxidase had two reduced forms with the Soret band either at 446 or 435 nm, and thyroid peroxidase lacked a reduced form having the 446-nm band. From comparison of their pyridine hemochrome spectra, epsilon mM at 413 nm of thyroid peroxidase was estimated to be 114, being the same as that of lactoperoxidase. The cyanide inhibition for the reaction of thyroid peroxidase was competitive with hydrogen peroxide and the inhibition constant was in rough accord with the dissociation constant of its cyanide complex measured from spectrophotometric titration. Azide inhibited the reaction with an inhibition constant which was about one one-thousandth of the dissociation constant for its spectrally discernible complex. The azide inhibition was not competitive with hydrogen peroxide and decreased as the reaction proceeded. Aminotriazole inhibited the reaction strongly, and the inhibition was augmented during the reaction. These inhibition patterns of azide and aminotriazole were more or less observed in the reaction of lactoperoxidase, but not in the case of horseradish peroxidase. Characteristics of animal peroxidases are discussed.     

Correlation between three-dimensional power Doppler and morphometric measurement of endometrial vascularity at the time of embryo implantation in women with unexplained recurrent miscarriage

Power Doppler in combination with three-dimensional (3D-PD) ultrasonography has been used as a noninvasive tool to evaluate the vascularity. However, it is unclear whether 3D-PD can accurately reflect endometrial vascularization and replace the invasive endometrial biopsy. This study aims to investigate the correlation between 3D-PD and micro vessel morphometric measurement of endometrial vascularity. Twenty-five women with unexplained recurrent miscarriage were recruited for 3D-PD and endometrial biopsy on precisely day LH?+?7. Immunohistochemistry using vWF was employed to identify micro vessels in endometrial biopsy specimens followed by the use of morphometric technique to measure the mean vessel diameter and volume fractions. The vascularization index (VI), flow index (FI) and vascularization flow index (VFI) assessed by 3D-PD were calculated for both the endometrial and sub-endometrial regions. There were no significant correlations between any of the ultrasonographic measurements (endometrial thickness, endometrial volume, endometrial VI/FI/VFI, sub-endometrial volume, sub-endometrial VI/FI/VFI) and morphometric features (number of micro vessel, mean diameter of micro vessel and volume fraction measurement of vessel). This study indicates that endometrial vascularity assessed by 3D-PD could not be used to reflect changes in micro vessels of the endometrium at the time of embryo implantation in women with unexplained recurrent miscarriage.     

Hürthle cell Thyroid Carcinoma Presenting as A “Hot” Nodule

ObjectiveTo report an unusual clinical scenario and a rare histopathologic finding of Hürthle cell thyroid carcinoma in a patient with an autonomous thyroid nodule.MethodsWe describe the presentation and clinical course leading to the surprising histopathologic diagnosis of Hürthle cell carcinoma in a pediatric patient who was diagnosed with hyperthyroidism presenting as a solitary toxic nodule.ResultsA 13-year-old white girl presented with a recent history of a palpable thyroid nodule during a routine primary care clinic visit. She was asymptomatic, and thyroid function tests revealed a suppressed thyrotropin concentration, high-normal free thyroxine concentration, and elevated triiodothyronine concentration. The patient underwent dedicated thyroid ultrasonography revealing a 3.5-cm complex mass in the left lobe with increased central vascularity. Iodine 123 imaging of the thyroid demonstrated homogenous, hyperintense activity in the left lobe. The right lobe was not visualized. A solitary toxic nodule was diagnosed, and, considering her age, she was referred for surgical management. The patient underwent a left lobectomy with isthmusectomy. Pathologic examination revealed a 5-cm, encapsulated, well-differentiated Hürthle cell carcinoma with negative margins and no lymphovascular invasion. The patient underwent subsequent completion thyroidectomy with no evidence of residual carcinoma in the right thyroid lobe.ConclusionsMalignancy in autonomously functioning thyroid nodules is rare. Most of the thyroid nodules presenting as “hot” on radioiodine scintigraphy are benign follicular adenomas. However, this case represents a rare clinical entity, and it highlights the need for clinicians to be vigilant and aware that occasionally carcinomas can masquerade as scintigraphic “hot” nodules. (Endocr Pract. 2011;17:e68-e72)     

Color-Flow Doppler Sonography in Patients with Subclinical Thyroid Dysfunction

ObjectiveTo assess the value of color-flow Doppler sonography (CFDS) in evaluating intrathyroidal blood flow and velocity in patients with subclinical thyroid dysfunction.MethodsIn this prospective study, patients with subclinical hypothyroidism, patients with subclinical hyperthyroidism, and euthyroid patients without known thyroid autoimmune disease who served as controls were included. Subclinical thyroid dysfunction was defined as normal serum free thyroxine (FT₄) and free triiodothyronine (FT₃) in the presence of high (subclinical hypothyroidism), or lowsuppressed (subclinical hyperthyroidism) serum thyrotropin (TSH) levels. Serum FT₄, FT₃, TSH, and antibodies to thyroid peroxidase and thyroglobulin were measured in all participants. In addition, TSH receptor antibody levels were determined in patients with subclinical hyperthyroidism. All participants underwent conventional sonography and CFDS. Mean peak systolic velocity (PSV) and resistive index were obtained from multiple extranodular thyroid parenchyma samplings and inferior thyroid artery measurements.ResultsThe study population included 27 patients with subclinical hypothyroidism, 15 patients with subclinical hyperthyroidism, and 20 euthyroid patients. Patients with subclinical hypothyroidism had significantly higher mean intrathyroidal PSV values than control patients (19.9 ± 5.6 cm/s vs 15.7 ± 4.4 cm/s; P = .008), whereas patients with subclinical hyperthyroidism had significantly higher mean PSV values than control patients at the inferior thyroid artery level (29.7 ± 10.7 cm/s vs 21.9 ± 6.8 cm/s; P = .014). Compared with control patients, a greater proportion of patients with subclinical hypothyroidism and patients with subclinical hyperthyroidism had marked CFDS patterns (78% vs 15% [P <.001] and 53% vs 15%; [P <.001], respectively). A significant association was found between positivity for thyroid autoantibodies and intense CFDS patterns. No correlation was found between TSH or thyroid hormone levels and CFDS pattern or blood flow velocity.ConclusionWe have demonstrated that significantly increased thyroid blood flow velocity and vascularity are already present in patients with mild thyroid dysfunction.(Endocr Pract. 2010;16:376-381)     

High-Resolution Sonography: A New Technique to Detect Nerve Damage in Leprosy

Background

Leprosy is the most common treatable peripheral nerve disorder worldwide with periods of acute neuritis leading to functional impairment of limbs, ulcer formation and stigmatizing deformities. Since the hallmarks of leprosy are nerve enlargement and inflammation, we used high-resolution sonography (US) and color Doppler (CD) imaging to demonstrate nerve enlargement and inflammation.

Methology/Principal Findings

We performed bilateral US of the ulnar (UN), median (MN), lateral popliteal (LP) and posterior tibial (PT) nerves in 20 leprosy patients and compared this with the clinical findings in these patients and with the sonographic findings in 30 healthy Indian controls.The nerves were significantly thicker in the leprosy patients as compared to healthy controls (p<0.0001 for each nerve). The two patients without nerve enlargements did not have a type 1 or type 2 reaction or signs of neuritis. The kappa for clinical palpation and nerve enlargement by sonography was 0.30 for all examined nerves (0.32 for UN, 0.41 for PN and 0.13 for LP). Increased neural vascularity by CD imaging was present in 39 of 152 examined nerves (26%). Increased vascularity was observed in multiple nerves in 6 of 12 patients with type 1 reaction and in 3 of 4 patients with type 2 reaction. Significant correlation was observed between clinical parameters of grade of thickening, sensory loss and muscle weakness and US abnormalities of nerve echotexture, endoneural flow and cross-sectional area (p<0.001).

Conclusions/Significance

We conclude that clinical examination of enlarged nerves in leprosy patients is subjective and inaccurate, whereas sonography provides an objective measure of nerve damage by showing increased vascularity, distorted echotexture and enlargement. This damage is sonographically more extensive and includes more nerves than clinically expected.     

Free diiodotyrosine effects on protein iodination and thyroid hormone synthesis catalyzed by thyroid peroxidase.

Free diiosotyrosine exerts two opposite effects on the reactions catalyzed by thyroid peroxidase, thyroglobulin iodination and thyroid hormone formation. 1. Inhibition of thyroglobulin iodination catalyzed by thyroid peroxidase was observed when free diiodotyrosine concentration was higher than 5 muM. This inhibition was competitive, suggesting that free diiodotyrosine interacts with the substrate site(s) of thyroid peroxidase. Free diiodotyrosine also competively inhibited iodide peroxidation to I2. 2. Free diiodotyrosine, when incubated with thyroid peroxidase in the absence of iodide was recovered unmodified; in the presence of iodide an exchange reaction was observed between the iodine atoms present in the diiodotyrosine molecule and iodide present in the medium. Using 14C-labelled diiodotyrosine, 14C-labelled non-iodinated products were also observed, showing that deiodination occurred as a minor degradation pathway. However, no monoiodo[14C]tyrosine or E114C]tyrosine were observed. Exchange reaction between free diiototyrosine and iodide is therefore direct and does not imply deiodination-iodination intermediary steps. Thyroglobulin inhibits diiodotyrosine-iodide exchange and vice versa, again suggesting competition for both reactions. These results support, by a different experimental approach, the two-site model for peroxidase previously described by us in this journal. 3. Free diiodotyrosine when present at a very low concentration, 0.05 muM, exerts a stimulatory effect on throid hormones synthesis. The relationship between diiodotyrosine concentration and thyroid hormone synthesis give an S-shaped curve, suggesting that free diiodotyrosine acts as a regulatory ligand for thyroid peroxidase. Evidence is also presented that free diiodotyrosine is not incorporated into thyroid hormones. Therefore, thyroid peroxidase catalyzes only intra-molecular coupling between iodotyrosine hormonogenic residues. 4. Finally, although no direct proof exists that these free diiodotyrosine effects upon thyroglobulin iodination and thyroid hormone synthesis are physiologically significant, such a possibility deserves further investigation.     

An Immunohistochemical Study of Leu 7 and PCNA Expression in Thyroid Neoplasms

Monoclonal Antibody (MoAb) HNK, or anti-leu-7, is reactive with several neuroendocrine and nonneuroendocrine tumors. The aim of this study is to examine anti-leu-7 reactivity in thyroid neoplasms and its relationship to cellular proliferation as determined by anti-PCNA reactivity. The expression of anti-leu-7 in 56 thyroid neoplasms (24 papillary carcinomas, 14 follicular carcinomas, two medullary carcinomas and 16 follicular adenomas) was examined immunohistochemically. Papillary and follicular thyroid carcinomas reacted with anti-leu-7 in a membranous and cytoplasmic pattern in 88% and 93% of cases, respectively. The adjacent benign tissues were nonreactive. Only eight cases diagnosed as follicular adenomas were reactive with anti-leu-7. Furthermore, the mean proliferative index (PI), as measured by the percentage of nuclei immunoreactive with anti-PCNA, was greater than 30% in all thyroid neoplasms reactive with anti-leu-7. The PI was 58% for papillary carcinomas and 68% and 48% for follicular carcinomas, and follicular adenomas, respectively. Lesions originally classified as follicular adenomas that were nonreactive with anti-leu-7 had a PI of 24% and were reclassified as hyperplastic nodules. These data suggest that anti-leu-7 may be useful for characterizing thyroid neoplasia.     

Comparative studies of nuclear DNA content in benign and malignant thyroid lesions

Currently available data suggest that DNA aneuploidy is associated with aggressive behavior of and unfavorable prognosis in several malignant human tumors as compared with diploid malignancies. However, the diagnostic and prognostic importance of flow cytometric DNA measurements in the case of thyroid neoplasms remains controversial. Therefore, the aim of our study was to evaluate utility of DNA index (DI) and proliferative index (PI) in distinguishing benign from malignant thyroid lesions taking into account the possible influence of intra-tumor heterogeneity and tissue preparation mode on DNA flow-cytometry measurements. A retrospective study was performed on 71 paraffin-embedded specimens from 57 patients with benign and malignant thyroid pathologies: 13 colloid goitres, 12 parenchymatous goitres, 19 adenomas and 13 carcinomas. In 14 of 57 cases two separate specimens taken from different areas of the same lesion were analysed and DNA parameters were compared. Additionally, flow cytometry DNA analysis was parallelly performed on 3 adjacent but differently processed tissue sections (fresh, formalin-fixed and paraffin-embedded) taken from each of 26 surgically excised thyroid lesions. DNA content was also analysed in both fresh and formalin-fixed twin specimens of normal pig thyroid glands (N = 6). We demonstrated that all tumors diagnosed as thyroid carcinomas were associated with abnormal nuclear DNA content although aneuploidy was not found specific to malignant thyroid tumors. Aneuploid samples of benign thyroid lesions exhibited higher proliferative activity, expressed as mean PI values, than diploid ones. In carcinomas the mean PI values were significantly higher than in benign lesions, independently whether they concerned aneuploid or diploid tissues. Considering intra-tumor heterogeneity, the flow cytometric DNA parameters can be assumed as reproducible despite differences in the mode of tissue fixation and preparation for analysis.     

An Immunohistochemical Study of Leu 7 and PCNA Expression in Thyroid Neoplasms

Monoclonal Antibody (MoAb) HNK, or anti-leu-7, is reactive with several neuroendocrine and nonneuroendocrine tumors. The aim of this study is to examine anti-leu-7 reactivity in thyroid neoplasms and its relationship to cellular proliferation as determined by anti-PCNA reactivity. The expression of anti-leu-7 in 56 thyroid neoplasms (24 papillary carcinomas, 14 follicular carcinomas, two medullary carcinomas and 16 follicular adenomas) was examined immunohistochemically. Papillary and follicular thyroid carcinomas reacted with anti-leu-7 in a membranous and cytoplasmic pattern in 88% and 93% of cases, respectively. The adjacent benign tissues were nonreactive. Only eight cases diagnosed as follicular adenomas were reactive with anti-leu-7. Furthermore, the mean proliferative index (PI), as measured by the percentage of nuclei immunoreactive with anti-PCNA, was greater than 30% in all thyroid neoplasms reactive with anti-leu-7. The PI was 58% for papillary carcinomas and 68% and 48% for follicular carcinomas, and follicular adenomas, respectively. Lesions originally classified as follicular adenomas that were nonreactive with anti-leu-7 had a PI of 24% and were reclassified as hyperplastic nodules. These data suggest that anti-leu-7 may be useful for characterizing thyroid neoplasia.     

A single nuclear polymorphism in let-7g binding site affects the doubling time of thyroid nodule by regulating KRAS-induced cell proliferation

As an indicator for the malignancy of thyroid nodules (TN), the doubling time of TN was studied in this study to evaluate the effect of rs712 polymorphism on the progression of TN. In addition, we aimed to study the potential molecular mechanisms underlying the pathological effect of rs712 polymorphism upon TN. A Taqman method was used to genotype the patients according to their rs712 polymorphism. Real-time polymerase chain reaction, western blot, Terminal deoxynucleotidyl transferase dUTP nick end labeling assay and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay was conducted to study the correlation between KRAS expression and the pathological effect of rs712 polymorphism. In-silicon analysis and luciferase assay were utilized to establish the regulatory relationship between let-7g and KRAS. KRAS messenger RNA (mRNA)/protein levels in the GG group were upregulated with a decreased apoptosis index. KRAS mRNA was validated to be a virtual target of let-7g. In addition, the mRNA/protein level of KRAS as well as cell proliferation index was decreased in primary thyroid cancer cells genotyped as TT/TG and transfected with KRAS small interfering RNA (siRNA)/let-7g precursors. The cell apoptosis index was evidently elevated in the KRAS siRNA/let-7g precursors group compared with that in the scramble controls. Moreover, KRAS mRNA/protein only showed slight reduction when GG-genotyped primary thyroid cancer cells were transfected by let-7g precursors. Additionally, let-7g precursors exhibited no significant effect on cell proliferation index or cell apoptosis in GG cells. Rs712 polymorphism T>G in the 3′-untranslated region of KRAS interrupts the interactions between let-7g and KRAS mRNA, leading to a higher cell proliferation index and reduced doubling time of TN.     

甲状腺结节良恶性的彩色多普勒超声特征及其诊断价值分析

目的:研究甲状腺结节良恶性的彩色多普勒超声特征及其诊断价值。方法:选取从2016年3月~2019年2月于我院接受手术治疗的甲状腺疾病患者300例作为研究对象,均予以彩超检查,比较甲状腺良恶性结节的超声特征(主要包括直径、钙化情况、边界、回声、血流状况)。以病理活检结果为金标准,分析彩超诊断甲状腺结节良恶性的敏感性、特异性以及准确度。对比甲状腺良恶性结节的血流分型情况以及各项血流动力学参数。结果:恶性结节超声特征直径≥2 cm、有钙化、边界模糊、无回声/低回声、血流丰富人数占比均高于良性结节(均P<0.05)。以手术病理组织活检结果作为金标准,彩色多普勒超声诊断甲状腺结节的敏感性、特异性以及准确度分别为97.73%、86.11%、96.33%。甲状腺良性结节血流分型为Ⅰ型、Ⅱ型人数占比高于恶性结节,而Ⅲ型、Ⅳ型人数占比低于恶性结节(均P<0.05)。甲状腺良性结节的收缩期峰值血流速度(PSV)、阻力指数(RI)均低于恶性结节,而舒张末期血流速度(EDV)高于恶性结节(均P<0.05)。结论:彩色多普勒超声对甲状腺结节良恶性的鉴别价值较高,且具有较高的敏感性、特异性以及准确度,可为甲状腺良恶性结节的早期诊断、临床治疗提供重要的参考依据。     

支气管哮喘小鼠模型气道血管变化及其影响因子分析

目的明确支气管哮喘时血管网络及血管内皮细胞变化,以及血管内皮生长因子（VEGF）亚型及其受体在支气管哮喘小鼠模型气管及肺组织中的变化及作用。方法在建立小鼠支气管哮喘模型的基础上,应用免疫荧光染色和HE染色观察气道旁血管密度变化并计数不同血管单位长度上内皮细胞数量,应用逆转录多聚酶链反应（RT-PCR）方法检测气管和肺组织血管内皮生长因子（VEGF）亚型及其受体mRNA表达情况。结果1.随着疾病时间的延长,小鼠气道壁血管密度增加,血管内皮细胞数量逐渐增加,特别在慢性期小血管尤为明显;2.应用RT-PCR技术及琼脂糖凝胶电泳,小鼠气管及肺组织VEGF120,VEGF164,VEGF188和VEGF205各个亚型mRNA均增高。其中VEGF164在气管组织,VEGF188在周围肺组织中mRNA表达在慢性哮喘期明显增高,少见的亚型VEGF144只在周围肺组织中检测到,而在支气管组织中无表达;VEGFR1 mRNA水平没有明显变化,而VEGFR2在正常气管组织中未检测到,而在支气管哮喘气管组织明显表达,并且在支气管哮喘慢性期高于急性期。结论随着疾病的进展,小鼠支气管哮喘时气道存在血管密度及血管内皮细胞数量增加,VEGF在此过程中起着重要的作用,各亚型的作用存在差异。另外,VEGFR2在支气管哮喘中对于介导和增强VEGF信号和VEGF活性起着重要的作用,并且可能是导致VEGF诱导小鼠气道血管再生与重塑的重要介质。     

甲亢性肝损害116例临床分析

目的探讨甲状腺功能亢进症（甲亢）肝损害的临床特点。方法收集228例甲亢患者的临床资料,分为肝损害组及无肝损害组,对两组患者的年龄、性别、甲亢病程、肝功能及甲状腺功能等指标进行分析比较。结果 228例甲亢患者中发生肝损害116例,发生率为50.72%。甲亢患者的性别与甲亢性肝损害的发生率无相关性;而年龄越大甲亢性肝损害发生率越高,病程越长甲亢性肝损害发生率也越高。甲亢性肝损害患者甲状腺功能指标TT4、FT3明显高于甲亢肝功能正常的患者,差异有统计学意义（P〈0.05）;肝功能测定以ALT、ALP升高多见。结论甲亢性肝损害的发病率较高,病情的严重程度与年龄、病程、甲状腺激素水平有密切关系;建议临床医生对初诊及复诊甲亢患者进行肝功能常规测定,以便合理选用治疗方案,使甲亢性肝损害得以及早治疗。     

Vascular supply to the ventral pelvic region of anurans as related to water balance

The ventral pelvic integument of anurans in hypervascular as compared to other skin regions. Recent studies indicate that this area is primarily responsible for water uptake and rehydration. Nine species representing four genera of terrestrial and aquatic Anura were dissected for comparison of vascularity in the pelvic area. Major differences in the ventral pelvic integumental vessels were found between aquatic and terrestrial genera. These variations are described, and names are suggested for previously unnamed vessels. Changes in vascularity are discussed and related to the literature on Anura pertinent to rehydration rates, tolerance of desiccation, resistance to desiccation, and habitat. Data from this study and previous studies suggest a correlation among the parameters discussed and habitat. The suggestion is made that when species are classified as xeric, mesic, or aquatic on the basis of the habitat in which they live, their responses to rehydration, tolerance to desiccation, and vasculatity should be considered, as these characteristics more accurately represent the micro-habitat.     

A quantitative study of peroxidase activity in unfixed tissue sections of the guinea-pig thyroid gland

Summary A technique for the cytochemical demonstration of peroxidase activity in unfixed guinea-pig thyroid tissue is described in this paper. The substrate 3,3-diaminobenzidine tetrahydrochloride (DAB) is oxidized by the peroxidase to form an insoluble reaction product. Optimal results were obtained after 20 min incubation at 37° C in reaction medium containing 1.4mm DAB (in 0.1m Tris-HCl) and 0.15mm hydrogen peroxide at pH 8.0. Peroxidase activity was seen in the thyroid follicle cells as a diffuse brown reaction product (which was more dense and granular in erythrocytes). The enzyme activity was quantified using a scanning-integrating microdensitometer, and the effects of two specific peroxidase inhibitors were evaluated. Both 3-amino-1,2,4-triazole and methimazole inhibited peroxidase activity in the follicle cells (enzyme activity was still seen in the erythrocytes), maximal inhibition occurring at 10mm. Stimulation of peroxidase in the thyroid was observedin vivo (1 I.U. TSH administered every 8 h for two days), with the maximal stimulation occurring after 1 day.