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排序方式: 共有4380条查询结果,搜索用时 15 毫秒
951.
Patrizia Agretti Giuseppina De Marco Alessandra Capodanno Eleonora Ferrarini Antonio Dimida Daniela Sansone Paola Collecchi Aldo Pinchera Paolo Vitti Massimo Tonacchera 《Thyroid》2007,17(9):861-868
Loss-of-function mutations of the thyrotropin receptor (TSHr) may be responsible for congenital hypothyroidism or isolated hyperthyreotropinemia. To study cell surface expression of inactivating TSHr mutations detected in patients with isolated hyperthyreotropinemia (L252P, Q8fsX62, P27T, E34K, R46P, D403N, W488R, and M527T), we used the Agilent 2100 bioanalyzer to perform microchip flow cytometry analysis. The previously described TSHr inactivating mutation T477I was used as control. The level of receptor expression in COS-7 cells transfected with the T477I measured by binding assay was four times lower with respect to the wild-type TSHr. The very low expression of T477I was confirmed by fluorescence-activated cell sorting (FACS) analysis and by microchip flow cytometry analysis, suggesting that this method can be a reliable system to measure receptor cell surface expression. Other inactivating TSHr mutations were expressed in COS-7 cells for binding studies, FACS analysis, and microchip flow cytometry analysis. Binding studies showed that L252P, Q8fsX62, P27T, E34K, R46P, D403N, W488R, and M527T mutants had a low expression at the cell surface, as demonstrated by Bmax values. Data obtained by binding studies were in good agreement with data obtained by FACS analysis and microchip flow cytometry analysis. In conclusion, the low number of cells required for analysis and the ease of use make the microchip flow cytometry analysis a very reliable and favorable system to study cell surface expression of TSHr mutations. 相似文献
952.
Giuseppe Stabile MD Serge A. Trines MD Elena Arbelo MD Nikolaos Dagres MD Josep Brugada MD Josef Kautzner MD Evgeny Pokushalov MD Aldo P. Maggioni MD Cecile Laroche MSc Matteo Anselmino MD Roy Beinart MD Vassil Traykov MD Carina Blomström Lundqvist MD 《Pacing and clinical electrophysiology : PACE》2019,42(3):313-320
953.
BACKGROUND: More patients are being diagnosed with prostate cancer at an earlier age with earlier stage disease because of advances in screening and detection. Investigators continue to explore the use of hormone therapy, particularly luteinizing hormone-releasing hormone (LHRH) analogues, earlier in the course of disease. OBJECTIVE: This review summarizes clinical evidence regarding the safety and efficacy of LHRH analogues in the treatment of locoregional disease or following biochemical failure. METHODS: Relevant information from clinical studies was identified through a MEDLINE search of the medical literature published in English in the last 5 years (search terms: LHRH and prostate cancer). The search included prospective and retrospective clinical studies on LHRH therapy in locally advanced prostate cancer. Additional relevant publications published before 1999 were identified from citations in the resulting articles. RESULTS: The available clinical evidence suggests that the use of LHRH analogues as adjuvant or neoadjuvant therapy in conjunction with radiation therapy may improve survival outcomes. Few studies have evaluated the use of LHRH analogues after biochemical failure. However, several related studies indicate that initiating hormone therapy earlier rather than later may provide some clinical benefit. When considering early initiation of LHRH therapy, the potential risks of long-term treatment must be considered. Physiologic changes, such as deterioration of body composition and bone quality, may have important effects on the risk of developing cardiovascular disease and osteoporosis. CONCLUSIONS: Although some clinical evidence supports the use of LHRH analogues as adjuvant or neoadjuvant therapy or following biochemical failure, further study is needed. In the meantime, clinicians should carefully weigh the potential benefits and risks of early hormone therapy when making treatment decisions. 相似文献
954.
Enrico Di Cesare Aldo Spadaro Antonino Ajello Oscar Ferraù Nunziata Alessi Carmelo Luigiano Rossana Melluso Maria A Freni 《Clinical chemistry and laboratory medicine》2005,43(8):823-826
It has been suggested that soluble CD30 (sCD30) serum levels in chronic hepatitis C are correlated with the activity of the disease and with the outcome of interferon (IFN) treatment. In this study, sCD30 serum levels in 25 patients with chronic hepatitis C, before and after treatment with IFN-2alpha, were measured. A total of 20 healthy subjects were used as controls. High sCD30 levels in serum were found in 36% of patients and in 5% of controls. In patients with sCD30 levels above or within the normal range, no significant differences in age, gender, serum transaminases and histology activity index were found. In relation to IFN treatment, only responder patients had serum sCD30 higher than controls, although the difference between responders and non-responders was not significant. No changes from baseline values were observed after treatment. Although high, sCD30 serum levels in chronic hepatitis C are not correlated with the disease activity, are not affected by IFN treatment and are not predictors of response to IFN treatment. 相似文献
955.
Biagini MR Tozzi A Milani S Grippo A Amantini A Capanni M Galli A Surrenti C 《European journal of gastroenterology & hepatology》2008,20(2):122-126
BACKGROUND AND AIMS: Fatigue is considered to be a specific manifestation of primary biliary cirrhosis (PBC). Recent reports have, however, questioned these findings. Considering the high rate of comorbidities in PBC patients and the fact that fatigue is a multifactorial symptom, we hypothesized that it might also be due to nonhepatic causes. Our aim was to evaluate fatigue in PBC patients and its relationship with comorbidities and depression. METHODS: We enroled 49 Italian PBC patients (44 women; mean age: 58.9 years, range: 21-73 years) and 30 matched healthy controls, who completed the Fatigue Impact Scale (FIS), Modified FIS (MFIS), Fatigue Severity Score (FSS) and Rand Medical Outcomes Study Depression Screener. Comorbidities and several clinical and biochemical data were investigated. Linear regression, analysis of variance and post-hoc analysis were applied. RESULTS: Fatigue was higher in patients than in controls (FIS: 33 vs. 24; MFIS: 24 vs. 14; FSS: 3.3 vs. 1.9). Physical domain was significantly different in all the three questionnaires (FIS: P=0.05; MFIS: P=0.002; FSS: P=0.0002). Comorbidities (38% of patients) were independently associated with higher fatigue scores (FIS: 45; MFIS: 32; FSS: 3.3). Depressed patients (30%) were more fatigued, even if not always significantly (FIS: 43; MFIS: 29; FSS: 3.5), than controls and patients with no depression. Patients without comorbidities or depression (51%) did not have higher fatigue than controls (FIS: 20; MFIS: 17; FSS: 2.4). CONCLUSIONS: Fatigue in patients with PBC was higher, but not always significantly, than in healthy controls. Comorbidities and depression might have played a role in its pathogenesis. Our data arouse doubts about the specificity of fatigue in PBC and the pathogenetic role of liver impairment. 相似文献
956.
OBJECTIVE: To investigate the risk of hypothyroidism after radioiodine (131I) treatment for hyperfunctioning thyroid nodules. DESIGN: Retrospective analysis of patients treated with 131I for hyperfunctioning thyroid nodules and followed up for a maximum of 20 years. PATIENTS: A total of 346 patients treated with 131I in the years 1975-95, for a single hyperfunctioning nodule. MEASUREMENTS: Hypothyroidism was defined as TSH levels > 3.7 mU/l. Kaplan-Meier survival analysis was used to analyse permanence of euthyroidism after 131I. A stepwise Cox proportional hazard model was used to identify factors influencing the progression to hypothyroidism. RESULTS: The cumulative incidence of hypothyroidism was 7.6% at 1 year, 28% at 5 years, 46% at 10 years and 60% at 20 years. Age (P < 0.01), 24-th 131I uptake (P < 0.05) and previous treatment with methimazole (MMI, P < 0.1) were associated with a faster progression towards hypothyroidism, while thyroid and nodule size, thyroid status at diagnosis and degree of extranodular thyroid parenchymal suppression had no influence. In hyperthyroid patients with partial parenchymal suppression, however, previous MMI treatment was the most important prognostic factor (P < 0.01). CONCLUSIONS: After 20 years of follow-up, 60% of patients treated with 131I for a single hyperfunctioning nodule are hypothyroid. Factors increasing the risk of hypothyroidism are age, 131I uptake and MMI pretreatment. The prognostic value of this last factor, however, depends on the degree of suppression of the extranodular thyroid parenchyma at the scan. 相似文献
957.
958.
Amebic liver abscess (ALA) highly endemic in most developing tropical countries is being encountered more frequently in other geographical areas maybe secondary to increased travel to areas where the disease is endemic as well as in the homosexual population. We report a classical clinical case of ALA in a 44 years old man diagnosed by ultrasound and positive seroameba titers who responded to oral imidazoles. 相似文献
959.
960.
Rossella Elisei Cristina Romei Maria Grazia Castagna Simonetta Lisi Agnese Vivaldi Pinuccia Faviana Michele Marinò Claudia Ceccarelli Furio Pacini Aldo Pinchera 《Thyroid》2005,15(12):1355-1361
Struma ovarii (SO) is usually asymptomatic and only in a few cases it is associated with thyrotoxicosis. The presurgical diagnosis is very uncommon. In the majority of cases a pelvic mass is discovered at physical examination or by abdominal ultrasound. Only the hystopathologic examination is able to reveal the characteristic features of SO, with thyroid cells organized in follicles as the main tumoral tissue constituent. The histologic recognition of malignancy is not easy and usually requires an exhaustive sampling of the lesion to evaluate the extracapsular invasion. We report the case of a 59-year-old woman who came to our observation for the fortuitous finding of elevated serum thyroglobulin (Tg) levels (600-800 ng/mL). Because the thyroid function was normal and the ultrasound showed only a subcentrimetric nodule, the clinical suspicious of a SO was considered. Ultrasound examination of the abdomen showed a solid mass of 2 cm in the left ovary. A (131)I uptake was observed at scintiscan in the site of the solid mass. Three months after the resection of the left ovary serum Tg levels were markedly reduced (106 ng/mL), and its values continued to decrease down to 34 ng/mL at last control. The histology showed that the ovarian mass was mainly constituted of thyroid tissue (98%), with no malignant features. The molecular analysis of several thyroid differentiation gene mRNAs in the SO tissue showed an abundant expression of all genes but pendrin (PDS). A reduced PDS mRNA expression might explain the defective thyroxine (T(4)) production. Despite the absence of malignant features, the expression of RET/PTC3 rearrangement was found, raising the possibility of a potential malignant nature of the tumor. A cancer-free period of 3-4 years, as in our patient, is not long enough to definitively exclude a late onset metastatic disease but, unfortunately, the patient died of nonmedical reasons. In conclusion, we report a case of SO that, to our knowledge, is the first in which the clinical suspicion arose from the inappropriately elevated presurgical serum levels of Tg. A quite exhaustive molecular analysis of thyroid specific genes and oncogenes provided two interesting findings: the low PDS mRNA expression, which may explain the low hormonal production and the absence of thyrotoxicosis and the presence of a RET/PTC3 rearrangement, which prompts the possibility of a late malignant evolution. 相似文献