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排序方式: 共有639条查询结果,搜索用时 0 毫秒
1.
Further evidence of dopamine transporter dysregulation in ADHD: a controlled PET imaging study using altropane. 总被引:4,自引:0,他引:4
Thomas J Spencer Joseph Biederman Bertha K Madras Darin D Dougherty Ali A Bonab Elijahu Livni Peter C Meltzer Jessica Martin Scott Rauch Alan J Fischman 《Neuropsychopharmacology》2007,62(9):1059-1061
BACKGROUND: The dopamine transporter (DAT) is known to be a key regulator of dopamine, and recent studies of genetics, treatment, and imaging have highlighted the role of DAT in attention-deficit/hyperactivity disorder (ADHD). The findings of in vivo neuroimaging of DAT in ADHD have been somewhat discrepant, however. METHOD: Dopamine transporter binding was measured using a highly selective ligand (C-11 altropane) and positron emission tomography (PET). The sample consisted of 47 well-characterized, treatment-na?ve, nonsmoking, non-comorbid adults with and without ADHD. Additionally, control subjects had few symptoms of ADHD. RESULTS: Results showed significantly increased DAT binding in the right caudate in adults with ADHD compared with matched control subjects without this disorder. CONCLUSIONS: These results confirm abnormal DAT binding in the striatum of adults with ADHD and provide further support that dysregulation of DAT may be an important component of the pathophysiology of ADHD. 相似文献
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Stress-activated protein kinases mediate cell migration in human airway epithelial cells 总被引:1,自引:0,他引:1
White SR Tse R Marroquin BA 《American journal of respiratory cell and molecular biology》2005,32(4):301-310
Airway epithelial cell (AEC) repair immediately after injury requires coordinated cell spreading and migration at the site of injury. Stress-activated protein kinases such as p38 MAPK and c-Jun N-terminal Protein Kinase (JNK) modulate several responses to cell stress and injury, but their role in AEC migration is not clear. We examined migration in confluent 16HBE14o(-) human AEC lines and in primary AEC grown on collagen-IV. Wounds were created by mechanical abrasion and followed to closure using digital microscopy. Inhibitors of either p38 extracellular signal-regulated kinase (ERK)1/2 (PD98059), mitogen-activated protein kinase (MAPK) (SB203580), or JNK (SP600125) could block cell migration substantially. Inhibiting JNK but not p38 MAPK or ERK1/2 blocked extension of cells into the wound region from the original line of injury. Initial migration was associated with phosphorylation of ERK, p38 MAPK, and JNK within 5-15 min. The downstream effector of p38, heat shock protein 27, also was phosphorylated rapidly after injury; phosphorylation could be blocked by prior treatment with SB203580 but not SP600125. The downstream effector of JNK, c-Jun, likewise was phosphorylated rapidly after injury and could be blocked by inhibiting JNK. Our data demonstrate that p38 MAPK, JNK, and ERK1/2 participate in the early stages of AEC migration. 相似文献
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The objective of this study is to compare relaxin's effect on transforming growth factor (TGF)- beta1 and latent TGF-beta1-binding protein (LTBP-1) in vaginal fibroblasts from women with stress urinary incontinence (SUI) to continent women (controls) in both phases of the menstrual cycle. Fibroblasts were treated with relaxin. TGF-beta1 levels were measured by enzyme-linked immunosorbent assay. LTBP-1 expression was evaluated by Western blot. In the proliferative phase, total TGF-beta1 level in the supernatant, cells, and extracellular matrix (ECM) of SUI fibroblasts decreased with increasing relaxin concentration (P < .05). Active TGF-beta1 levels increased at a low concentration of relaxin (P < .05) in the supernatant but decreased in the ECM of SUI fibroblasts at high concentration (P < .05). In the secretory phase, total TGF-beta1 levels decreased with relaxin treatment (P < .05) in the supernatant, cells and ECM of both women with SUI and controls. Relaxin decreased the levels of total and active TGF-beta1 in the ECM isolated from SUI vaginal fibroblasts. 相似文献
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Bertha M. Córdova-Sánchez Juan M. Mejía-Vilet Luis E. Morales-Buenrostro Georgina Loyola-Rodríguez Norma O. Uribe-Uribe Ricardo Correa-Rotter 《Clinical rheumatology》2016,35(7):1805-1816
Several classification schemes have been developed for anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), with actual debate focusing on their clinical and prognostic performance. Sixty-two patients with renal biopsy-proven AAV from a single center in Mexico City diagnosed between 2004 and 2013 were analyzed and classified under clinical (granulomatosis with polyangiitis [GPA], microscopic polyangiitis [MPA], renal limited vasculitis [RLV]), serological (proteinase 3 anti-neutrophil cytoplasmic antibodies [PR3-ANCA], myeloperoxidase anti-neutrophil cytoplasmic antibodies [MPO-ANCA], ANCA negative), and histopathological (focal, crescenteric, mixed-type, sclerosing) categories. Clinical presentation parameters were compared at baseline between classification groups, and the predictive value of different classification categories for disease and renal remission, relapse, renal, and patient survival was analyzed. Serological classification predicted relapse rate (PR3-ANCA hazard ratio for relapse 2.93, 1.20–7.17, p?=?0.019). There were no differences in disease or renal remission, renal, or patient survival between clinical and serological categories. Histopathological classification predicted response to therapy, with a poorer renal remission rate for sclerosing group and those with less than 25 % normal glomeruli; in addition, it adequately delimited 24-month glomerular filtration rate (eGFR) evolution, but it did not predict renal nor patient survival. On multivariate models, renal replacement therapy (RRT) requirement (HR 8.07, CI 1.75–37.4, p?=?0.008) and proteinuria (HR 1.49, CI 1.03–2.14, p?=?0.034) at presentation predicted renal survival, while age (HR 1.10, CI 1.01–1.21, p?=?0.041) and infective events during the induction phase (HR 4.72, 1.01–22.1, p?=?0.049) negatively influenced patient survival. At present, ANCA-based serological classification may predict AAV relapses, but neither clinical nor serological categories predict renal or patient survival. Age, renal function and proteinuria at presentation, histopathology, and infectious complications constitute the main outcome predictors and should be considered for individualized management. 相似文献
6.
Gichane Margaret W. Rosenberg Nora E. Zimmer Catherine Pettifor Audrey E. Maman Suzanne Maseko Bertha Moracco Kathryn E. 《AIDS and behavior》2022,26(3):822-832
AIDS and Behavior - Transactional sex increases HIV risk among adolescent girls and young women (AGYW). Understanding the individual and dyadic nature of transactional sex may provide evidence for... 相似文献
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John A. Santoshi Prashant N. Chaware Abhijit P. Pakhare Bertha A. D. Rathinam 《Journal of hand and microsurgery》2015,7(1):73-78
Distal radius fractures are often treated using percutaneous Kirschner wires (K-wires). The sensory nerves in this area, extensor tendons, radial artery and cephalic vein are at risk of injury in this procedure. We undertook a cadaveric investigation to identify probability of damage to these ‘at risk’ structures by measuring their distances in relation to standard K-wire sites. Nine upper limbs from six formalin-preserved cadavers were studied. Four K-wires were placed percutaneously simulating fixation of a distal radius fracture. Careful dissection was done preserving the original position of neurovascular and tendinous structures. Distances to relevant soft-tissue structures from each K-wire were measured using an electronic digital caliper. Distance of superficial nerves from radial styloid and Lister’s tubercle was measured to determine their ‘safe distance’ from these fixed landmarks. None of the superficial nerves were injured by a K-wire. Cephalic vein had been pierced on 4 occasions (4/18) and extensor tendons on 3 occasions (3/18). Wilcoxon signed-rank test was used to compare distance of the superficial nerves from radial styloid and Lister tubercle, and the latter was found to be the safer option. This study highlights the inherent danger in percutaneous K-wire fixation of wrist fractures. Limited size of the area, where K-wires can be positioned, and anatomic variations of neurovascular structures pose obstacles in developing guidelines for reducing risk of injury. We advocate use of mini-open approach and guiding devices to avert complications of inadvertent impalement and damage to these structures. 相似文献
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