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PAQR3, also known as RKTG (Raf kinase trapping to Golgi), is a member of the progestin and adipoQ receptor (PAQR) family. The role of PAQR3 as a tumor suppressor has recently been established in different types of human cancer in which PAQR3 exerts its biological function through negative regulation of the oncogenic Raf/MEK/ERK signaling. Multiple studies have found that PAQR3 downregulation frequently occurs in human cancers and is very often associated with tumor progression and shortened patients’ survival. Moreover, restoring the expression of PAQR3 could induce apoptosis and inhibit proliferation and invasiveness of cancer cells. Downregulation of PAQR3 by oncogenic microRNAs has also been reported. In this review, we summarized current knowledge concerning the role of PAQR3 in tumor development. To our knowledge, this is the first review on the role of this novel tumor suppressor.  相似文献   
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Elevation of serum parathyroid hormone (PTH) level in eucalcemic patients after parathyroidectomy for primary hyperparathyroidism has been described in up to 40% of patients, but little is known about its etiology or clinical significance. To better understand the cause of this phenomenon, we studied 49 patients without renal dysfunction or osteomalacia who underwent parathyroidectomy for primary hyperparathyroidism. Patients were categorized into 2 groups based on their serum PTH and calcium levels after parathyroidectomy: (1) elevated PTH with eucalcemia (n = 21), (2) normal PTH with eucalcemia (n = 28). Elevation of serum PTH with eucalcemia after parathyroidectomy occurred in 43% of patients. Patients in group 1 had significantly higher preoperative and postoperative mean serum PTH levels and significantly lower postoperative serum levels of 1,25(OH)(2)D(3), 1,25(OH)(2)D(3)/25(OH)D(3) ratio, and 1,25(OH)(2)D(3)/PTH ratio compared with patients in group 2. Serum PTH in group 1 patients normalized as early as 3 months, but remained elevated in some patients for more than 4 years, and was not associated with development of recurrent hypercalcemia. Normalization of serum PTH in group 1 patients was associated with significant increase in 1,25(OH)(2)D(3) and 1,25(OH)(2)D(3)/PTH ratio. Our data suggest that elevation of serum PTH in eucalcemic patients after parathyroidectomy is a frequently reversible state of resistance of the kidneys to PTH-mediated 1-alpha hydroxylation of 25(OH)D(3) and does not signify subsequent recurrence of hyperparathyroidism.  相似文献   
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More than a century ago, Ortner described a case of cardiovocal syndrome wherein he attributed a case of left vocal fold immobility to compression of the recurrent laryngeal nerve by a dilated left atrium in a patient with mitral valve stenosis. Since then, the term Ortner's syndrome has come to encompass any nonmalignant, cardiac, intrathoracic process that results in embarrassment of either recurrent laryngeal nerve-usually by stretching, pulling, or compression; and causes vocal fold paralysis. Not surprisingly, the left recurrent laryngeal nerve, with its longer course around the aortic arch, is more frequently involved than the right nerve, which passes around the subclavian artery.ObjectivesTo discuss the pathogenesis of hoarseness resulting from cardiovascular disorders involving the recurrent laryngeal nerve along with the findings of literature review.Materials and methodsThis paper reports a series of four cases of Ortner's syndrome occurring due to different causes.DesignCase study.ResultOrtner's syndrome could be a cause of hoarseness of voice in patients with cardiovascular diseases.ConclusionAlthough hoarseness of voice is frequently encountered in the Otolaryngology outpatient department, cardiovascular- related hoarseness is an unusual presentation. Indirect laryngoscopy should be routinely performed in all cases of heart disease.  相似文献   
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This paper focuses on the impact of selection bias in the context of extended, community-based prevention trials that attempt to “unpack” intervention effects and analyze mechanisms of change. Relying on dose-response analyses as the most general form of such efforts, this study provides two examples of how selection bias can affect the estimation of treatment effects. In Example 1, we describe an actual intervention in which selection bias was believed to influence the dose-response relation of an adaptive component in a preventive intervention for young children with severe behavior problems. In Example 2, we conduct a series of Monte Carlo simulations to illustrate just how severely selection bias can affect estimates in a dose-response analysis when the factors that affect dose are not recorded. We also assess the extent to which selection bias is ameliorated by the use of pretreatment covariates. We examine the implications of these examples and review trial design, data collection, and data analysis factors that can reduce selection bias in efforts to understand how preventive interventions have the effects they do.  相似文献   
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Dedifferentiation of human thyroid tumors is frequently found in humans. The effect of retinoids (13 cis-RA) was studied on the proliferation and differentiation of a human follicular cell line in vitro (UCLA R0 82 W-1). A significant and dose-dependent reduction (P less than 0.001) in cell number and [3H] thymidine uptake was found in cells exposed to 13 cis-RA up to 10 microM. Higher concentrations of 13 cis-RA, however, led to a dose-dependent restoration of cell proliferation. Various parameters of differentiation increased under the influence of 13 cis-RA (10 microM) over nonexposed cells. The 125I uptake increased 4-fold over that in control nonexposed cells (P less than 0.05). [125I] Epidermal growth factor binding increased 5-fold, and [125I] human TSH binding increased significantly after exposure to 13 cis-RA (P less than 0.02). Deiodinase activity, however, was significantly lower in 13 cis-RA exposed cells than in control cells. The present study shows that 13 cis-RA (10 microM) drives the tumor cells toward a more normal state of proliferation and differentiation.  相似文献   
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Intussusception in adults is a rare cause of abdominal pain. Unlike its paediatric counterpart, intussusception in adults is associated with obvious pathology. We describe a case of ileocolic intussusception extending to the splenic flexure. We were able to reduce the intussusception partially and pedicle was stapled carefully. The specimen was delivered through a small incision and right hemicolectomy was performed adhering to oncological principles. We recommend laparoscopic-assisted surgery is considered for adult intussusceptions.  相似文献   
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