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Thyroid nodules are commonly encountered during routine medical care. The main problem established by a discovery of a thyroid nodule is to discriminate between a benign and malignant lesion. Fine-needle aspiration (FNA) is the most widely used and cost-effective preoperative test for initial evaluation of a thyroid nodule. While the overall accuracy of FNA for classical papillary thyroid carcinoma (PTC) approaches 100%, it has limited accuracy with follicular lesions. Patients with a cytological report of indeterminate or follicular lesions are referred to surgery for a more accurate diagnosis. A more acute molecular-based test for thyroid nodules is needed not only to improve treatment decisions, but also to potentially reduce the long-term health costs. Several studies have looked into biologic markers that could be used as an adjuvant to distinguish the benign from malignant nodules. This review will focus on those biomarkers that are potentially useful in the diagnosis of thyroid lesions commonly classified as indeterminate. 相似文献
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Cryptogenic chronic hepatitis (CCH) is diagnosed in patients with persistently elevated aminotransferase levels of unknown
etiology. The workup of CCH patients must include a liver biopsy in order to exclude the largely unrecognized diagnosis of
seronegative autoimmune hepatitis (SAIH). Patients with SAIH have demographic, biochemical, and histologic features of autoimmune hepatitis
(AIH) and may be treated effectively with corticosteroids. Recognition and treatment of SAIH are necessary to prevent progression
to end-stage liver disease. We performed a retrospective review of a database of 3507 patients seen at our institution over
a 5-year period. Thirty patients with conventional AIH and an additional six patients with SAIH were identified. The two groups
were similar with respect to mean age, gender, and baseline biochemistries. Of the 20 AIH patients who had pretreatment liver
biopsies, 85% had moderate to severe interface hepatitis, compared to 83.3% of patients with SAIH. In the SAIH group, 83.3%
had advanced fibrosis (stage 3 or 4), versus 40% in the conventional AIH group (P = 0.16). All patients were treated with corticosteroids followed by azathioprine. The mean time to remission (normal ALT)
was similar in both groups, 2.6 vs. 2.7 months. Within 3 months, 88.9% of AIH patients and 66.7% of SAIH patients were in
remission. We conclude that a trial of corticosteroids is a reasonable therapeutic measure in patients with chronic hepatitis
that has features of AIH despite negative autoantibody markers. In most patients, clinical remission will be seen within 3
months, possibly avoiding progression to end-stage liver disease. 相似文献
75.
Folino AF Russo G Porta A Buja G Cerutti S Iliceto S 《International journal of cardiology》2007,120(1):102-107
BackgroundVasovagal syncope (VVS) results from a complex interaction among afferent vagal and sympathetic signals, cortical modulation and bulbar integration. The aim of our study was to evaluate the modifications of autonomic activity during Upright Tilt Test (UTT) in patients with unexplained syncope, and to correlate these changes with the specific cardiovascular reactions induced.Methods and resultsWe studied 90 patients with a mean age of 44 ± 17 yrs. Frequency domain analysis of heart rate variability (HRV) (normalized units) was performed on 2 periods of 300 beats: at baseline and after 5 min of 60° tilt. UTT was positive in 56 patients (62%). The responses were cardioinhibitory in 8, vasodepressive in 15, mixed in 33. Baseline LF and HF components did not show significant difference between subjects with positive or negative test (HF: 39 ± 21 versus 41 ± 22; LF: 50 ± 22 versus 49 ± 23). HRV during UTT showed similar changes in patients with positive or negative test. However, subjects with mixed or cardioinhibitory reactions were characterized by a relevant increase of LF during UTT (from 47 ± 23 to 66 ± 21), whereas the others by a non-significant decrease of the same component (from 57 ± 19 to 51 ± 31).ConclusionsPatients developing a reflex cardioinhibitory reaction during UTT were characterized by an increase of sympathetic activity during the test, that might represent an essential factor to induce a stronger vagal reaction on the sinus node. On the contrary, in subjects with vasodepressive reactions an inadequate enhancement of the sympathetic drive, probably causing a failure of peripheral vasoconstriction, was evidenced. 相似文献
76.
Natal D Urbinatti PR Malafronte Rdos S Rezende HR Cerutti C Sallum MA 《Revista do Instituto de Medicina Tropical de S?o Paulo》2007,49(5):323-326
Field collections of immatures and adults of Culicidae were carried out in the Rio Doce Valley, Espírito Santo State, aiming to increase knowledge on the anopheline species of that region. Considering all Culicidae species collected, among other anopheline it is noteworthy the presence of Anopheles darlingi, An. oswaldoi and An. costai. Regarding to An. darlingi, responsible for malaria outbreak in the low lands in that state, it was expected to confirm its presence in the area. The register of specimens of An. costai in the field collections is relevant, increasing the geographical distribution of the species and representing better knowledge of the Series Arribalzagia of the subgenus Anopheles. 相似文献
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Medina-Franco H Soto-Germes S Ulloa-Gómez JL Romero-Trejo C Uribe N Ramirez-Alvarado CA Robles-Vidal C 《Annals of surgical oncology》2008,15(6):1689-1695
Background Local ablative therapy of breast cancer represents the next frontier in the minimally invasive breast-conservation treatment.
We conducted a phase II trial to evaluate radiofrequency ablation (RFA) of invasive breast carcinomas.
Methods Consecutive patients from two Mexican Institutions with invasive breast cancers < 4 cm, with no multicentric tumors and no
previous chemotherapy were included in this trial. Under ultrasound guidance, the tumor and a 5 mm margin of surrounding breast
tissue were ablated with saline-cooled RFA electrode followed by surgical resection. Routine pathologic analysis and viability
evaluation with NADPH-diaphorase stain were performed to assess tumor ablation. Procedure-associated morbidity was recorded.
Results Twenty-five patients were included. Mean patient age was 55.3 years (range 42–89 years). Mean tumor size was 2.08 cm (range
0.9–3.8 cm). Fourteen tumors (56%) were <2 cm. The mean ablation time was 11 minutes using a mean power of 35 W. During ablation,
the tumors become progressively echogenic that corresponded with the region of severe RFA injury at pathologic examination.
Of the 25 patients treated, NADPH stain showed no evidence of viable malignant cells in 19 patients (76%), with significant
difference between tumors <2 cm (complete necrosis in 13 of 14 cases, 92.8%) vs. those >2 cm (complete necrosis 6 of 11 cases,
54.5%) (P < .05). No significant morbidity was recorded.
Conclusions RFA is a promising minimally invasive treatment of small breast carcinomas, as it can achieve effective cell killing with
a low complication rate. Further studies are necessary to optimize the technique and evaluate its future role as local therapy
for breast cancer. 相似文献