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991.
Transbronchial needle aspiration (TBNA) of pulmonary lesions without endobronchial affectation in combination with transbronchial biopsy (TBB) has been shown to increase diagnostic performance. The objective of this present study was to analyze whether the combination of TBNA with conventional TBB is a cost-effective approach.  相似文献   
992.
The insulin-like growth factor (IGF) signaling pathway has many important roles in normal cell growth and development. Remarkably, all of the components of this system (IGFs, receptors, and binding proteins) are expressed in human fetal adrenals. Beckwith-Wiedemann syndrome, a congenital overgrowth disorder characterized by a high risk of development of childhood tumors, is also distinguished by a high incidence of adrenocortical carcinomas. This disease has been associated with structural abnormalities at the 11p15 locus, which harbors the IGF2 gene as well as the genes coding for insulin, H19, and p57kip2. Notably, rearrangements at the 11p15 locus and overexpression of IGF2 were also described in sporadic adrenocortical tumors. In addition, the IGF2 overexpression was exclusively demonstrated in adults with adrenocortical tumors as a frequent feature of the malignant state. More recent studies demonstrated that the interaction of IGF-2 with IGF receptor type 1 (IGF-1R) plays also a pivotal role in adrenocortical tumorigenesis. IGF1R expression levels were significantly higher in pediatric adrenocortical carcinomas, suggesting that IGF1R expression represents a potential prognostic marker in this group of patients. These findings indicate that the IGF system is an important pathway for autonomous growth of adrenocortical cells and potential inhibitors of this system could be a rational therapeutic target for adrenocortical tumors.  相似文献   
993.

Background and objective

The goal of this study was to investigate the effects of low level laser therapy (LLLT) in osteoporotic rats by means of subjective histopathological analysis, deposition of collagen at the site of fracture, biomechanical properties and immunohistochemistry for COX-2, Cbfa-1 and VEGF.

Material and methods

A total of 30 female Wistar rats (12 weeks-old, ± 250 g) were submitted to ovariectomy (OVX). Eight weeks after the OVX, a tibial bone defect was created in all animals and they were randomly divided into 3 groups (n = 10): control bone defect group (CG): bone defects without any treatment; laser 60 J/cm2 group (L60): animals irradiated with LLLT, at 60 J/cm2 and laser 120 J/cm2 group (L120): animals irradiated with LLLT, at 120 J/cm2.

Results

In the laser treated groups, at both fluences, a higher amount of newly formed bone was evidenced as well as granulation tissue compared to control. Picrosirius analysis demonstrated that irradiated animals presented a higher deposition of collagen fibers and a better organization of these fibers when compared to other groups, mainly at 120 J/cm2. COX-2, Cbfa-1 or VEGF immunoreactivity was detected in a similar manner either 60 J/cm2 or 120 J/cm2 fluences. However, no differences were shown in the biomechanical analysis.

Conclusion

Taken together, our results support the notion that LLLT improves bone repair in the tibia of osteoporotic rats as a result of stimulation of the newly formed bone, fibrovascularization and angiogenesis.  相似文献   
994.
Aging represents a major risk factor for prostate cancer; however, mechanisms responsible for this relationship remain unclear. Preclinical and some clinical investigations support the protective role of selenium against prostate cancer possibly through the reduction of oxidative stress. While increased levels of oxidative stress together with decreases in selenium and the major cellular antioxidant glutathione (GSH) are common in tissues of old animals, there is little data available on these parameters in the prostate. In the present study we have compared the levels of selenium, GSH and protein-bound GSH (GSSP) in blood and prostate tissues in young (4-month), mature (12-month), old (18 month), and very old (24 month) male F344 rats. Each prostate lobe (dorsolateral, DL; anterior, AL; ventral, VL) was analyzed separately based upon their differing potential for prostate cancer development. At all ages, selenium levels were lowest in DL相似文献   
995.
Intracardiac metastases of thyroid carcinoma are a rare event. Their incidence is low in large autopsy series, and antemortem diagnosis is even less common. We present the case of a woman with advanced poorly differentiated thyroid carcinoma who had extensive intracardiac metastases. This case highlights the usefulness of echocardiography and magnetic resonance imaging in the diagnosis and differential diagnosis of cardiac metastases.  相似文献   
996.
Introduction. A study was conducted on histological patterns and biomolecular changes in Goitrogen-induced experimental rat thyroid tumors. The link between the histological types observed and N-ras, B-raf, and PI3KCA gene mutations widely reported in human thyroid cancers was explored. Material and Methods. An analysis was done on paraffin-embedded tumor tissue sections from Wistar rats receiving 1% potassium perchlorate (KClO(4)) added to the ad libitum drinking-water supply over an 18-month period. Three experimental subgroups were formed, each comprising 10 thyroids: subgroup I (control) consisted of thyroids from untreated controls; subgroups II and III (experimental) consisted of thyroids from KClO(4)-treated rats, displaying capsular, vascular, or both invasion but no metastasis (II), or distant metastasis (III). DNA was extracted from paraffin-embedded tissues. To test for the genetic mutations most widely reported in human thyroid cancers, exon 1 of the N-ras gene, exons 9 and 20 of the PI3KCA gene, and exon 15 of the B-raf gene were amplified and sequenced. Results. All tumors were of the follicular type. None of the 20 experimental rat thyroids displayed the expected gene mutations reported in humans. However, 90% of them contained four new B-raf gene mutations and all were silent and did not cause an amino acid substitution in the protein chain. Conclusions. Biomolecular analysis suggested that N-ras, PI3KCA, and B-raf gene mutations may not be involved in thyroid tumor formation using the experimental procedure applied in this study. But the four mutations in B-raf, though without functional repercussions, may be a specific marker for this tumor type.  相似文献   
997.
998.
999.
Several studies have shown that sleep fragmentation not only increases daytime sleepiness, but also deteriorates reaction time. Obstructive sleep apnea syndrome(OSAS)is characterized by interruptions in normal sleep patterns. Nasal Continuous Positive Airway Pressure(nCPAP)is the most frequently used treatment for OSAS. The objective of this investigation was to evaluate changes in daytime sleepiness levels and reaction time in apnea patients after nCPAP treatments of 1 and 3 months. The sample was composed of 51 obstructive sleep apnea patients(47 men and 4 women)with ages ranging between 30 and 65 years of age. Sleep apnea was diagnosed with a cardiorespiratory polygraph of the total hours of sleep. The Epworth Sleepiness Scale was used to assess daytime sleepiness. A BASIC software program was used to measure the simple perceptual reaction times in milliseconds. The results indicated statistically significant decreases in daytime sleepiness levels at 1 month(p?<?.000)and at 3 months(p?<?.000)of treatment. The results also showed statistically significant decreases in reaction times at one month(p?<?.000), as well as at 3 months(p?<?.000)of treatment. Results indicate an improvement in the vigilance levels of obstructive sleep apnea patients after 1 month and 3 months of nCPAP treatment.  相似文献   
1000.
Abstract

Objective: The determination of soft signs can be a conducive practice to understand the differential etiology between depression and anxiety. This study aims at examining malleolar hypoesthesia role in distinguishing between patients with generalised anxiety disorder (GAD) and major depression disorder (MDD).

Methods: This study examines the presence of malleolar hypoesthesia in patients with GAD (n?=?47) compared to patients with MDD (n?=?48) and healthy individuals (controls; n?=?99). The Wartenberg wheel, a medical device for neurological use, was employed to determine the presence of hypoesthesia on both sides of the ankles.

Results: The data revealed: i) MDD patients showed higher hypoesthesia than GAD patients (p?=?.008), ii) participants with hypoesthesia had higher anxiety and depression scores than participants without hypoesthesia (all p?<?.001) and iii) logistic regression model indicated that hypoesthesia can be a predictor of MDD relative to GAD diagnosis (Odds Ratio: 17.43 (1.40–217.09; p?=?.026)).

Conclusions: Malleolar hypoesthesia was higher in MDD than GAD. The detection of hypoesthesia may help to investigate the differential etiology between MDD and GAD diagnosis.  相似文献   
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