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991.
A Abi-Dargham M Laruelle J Krystal C D'Souza S Zoghbi R M Baldwin J Seibyl O Mawlawi G de Erasquin D Charney R B Innis 《Neuropsychopharmacology》1999,20(6):650-661
Deficits in gamma-amino-butyric acid (GABA) neurotransmitter systems have been implicated in the pathophysiology of schizophrenia for more than two decades. Previous postmortem and in vivo studies of benzodiazepine (BDZ) receptor density have reported alterations in several brain regions of schizophrenic patients. The goal of this study was to better characterize possible alterations of the in vivo regional distribution volume (VT) of BDZ receptors in schizoprenia, using the selective BDZ antagonist [123I]iomazenil and single photon emission computerized tomography (SPECT). Regional BDZ VT was measured under sustained radiotracer equilibrium conditions. The reproducibility and reliability of this measurement was established in four healthy volunteers. No differences in regional BDZ VT were observed between 16 male schizophrenic patients and 16 matched controls. No relationships were observed between BDZ VT and severity of psychotic symptoms in any of the regions examined. In conclusion, this study failed to identify alterations of BDZ receptors density in schizoprenia. If this illness is associated with deficits in GABA transmission, these deficits do not substantially involve BDZ receptor expression or regulation. 相似文献
992.
Stellman JM Smith RP Katz CL Sharma V Charney DS Herbert R Moline J Luft BJ Markowitz S Udasin I Harrison D Baron S Landrigan PJ Levin SM Southwick S 《Environmental health perspectives》2008,116(9):1248-1253
BACKGROUND: The World Trade Center (WTC) attacks exposed thousands of workers to hazardous environmental conditions and psychological trauma. In 2002, to assess the health of these workers, Congress directed the National Institute for Occupational Safety and Health to establish the WTC Medical Monitoring and Treatment Program. This program has established a large cohort of WTC rescue, recovery, and cleanup workers. We previously documented extensive pulmonary dysfunction in this cohort related to toxic environmental exposures. OBJECTIVES: Our objective in this study was to describe mental health outcomes, social function impairment, and psychiatric comorbidity in the WTC worker cohort, as well as perceived symptomatology in workers' children. METHODS: Ten to 61 months after the WTC attack, 10,132 WTC workers completed a self-administered mental health questionnaire. RESULTS: Of the workers who completd the questionnaire, 11.1% met criteria for probable post-traumatic stress disorder (PTSD), 8.8% met criteria for probable depression, 5.0% met criteria for probable panic disorder, and 62% met criteria for substantial stress reaction. PTSD prevalence was comparable to that seen in returning Afghanistan war veterans and was much higher than in the U.S. general population. Point prevalence declined from 13.5% to 9.7% over the 5 years of observation. Comorbidity was extensive and included extremely high risks for impairment of social function. PTSD was significantly associated with loss of family members and friends, disruption of family, work, and social life, and higher rates of behavioral symptoms in children of workers. CONCLUSIONS: Working in 9/11 recovery operations is associated with chronic impairment of mental health and social functioning. Psychological distress and psychopathology in WTC workers greatly exceed population norms. Surveillance and treatment programs continue to be needed. 相似文献
993.
Akhil Vaid Lili Chan Kumardeep Chaudhary Suraj K. Jaladanki Ishan Paranjpe Adam Russak Arash Kia Prem Timsina Matthew A. Levin John Cijiang He Erwin P. Bttinger Alexander W. Charney Zahi A. Fayad Steven G. Coca Benjamin S. Glicksberg Girish N. Nadkarni 《Clinical journal of the American Society of Nephrology》2021,16(8):1158
994.
Impact of sentinel node status and other risk factors on the clinical outcome of head and neck melanoma patients 总被引:2,自引:0,他引:2
Leong SP Accortt NA Essner R Ross M Gershenwald JE Pockaj B Hoekstra HJ Garberoglio C White RL Chu D Biel M Charney K Wanebo H Avisar E Vetto J Soong SJ;Sentinel Lymph Node Working Group 《Archives of otolaryngology--head & neck surgery》2006,132(4):370-373
OBJECTIVE: To determine the impact of sentinel lymph node (SLN) status and other risk factors on recurrence and overall survival in head and neck melanoma patients. DESIGN: The SLN Working Group, based in San Francisco, Calif, with its 11 member centers, the John Wayne Cancer Institute, and The University of Texas M. D. Anderson Cancer Center pooled data on 629 primary head and neck melanoma patients who had selective sentinel lymphadenectomy. A total of 614 subjects were analyzable. All centers obtained internal review board approval and adhered to the Health Insurance Portability and Accountability Act of 1996 regulations. A Cox proportional hazards model was used to identify factors associated with overall and disease-free survival. SETTING: Tertiary care medical centers. MAIN OUTCOME MEASURE: Clinical outcome of head and neck melanoma patients undergoing selective sentinel lymphadenectomy. RESULTS: Overall, 10.1% (n = 62) of the subjects had at least 1 positive node. Subjects with positive SLN status had significantly thicker tumors (mean thickness, 2.8 vs 2.1 mm; P < .001), and were more likely to have ulcerated tumors (P = .004). During the median follow-up of 3.3 years, the overall mortality from head and neck melanoma was 10%, with more than 20% experiencing at least 1 recurrence. Multivariate analysis showed that tumor site was an independent predictor of mortality; location on the scalp had a more than 3-fold (P < .001) greater mortality than tumors on the face. Tumor thickness was also an independent predictor of overall survival, and SLN status was the most important predictor of disease-free survival in the multivariate model (P < .001). Tumors on the scalp had the highest rate of recurrence, while those on the neck had the lowest. Tumor ulceration was the significant predictor of time to recurrence or disease-free survival (P < .001). CONCLUSION: In this multicenter study, SLN status and other risk factors have an effect on recurrence and/or overall survival. 相似文献
995.
小梁切除术联合丝裂霉素C是治疗青少年型开角型青光眼(junior open-angle glaucoma,JOAG)较常用的术式,缺点是存在低眼压性黄斑病变、滤过泡渗漏等潜在并发症的可能.前房角切开术是治疗原发性婴幼儿型青光眼较常用的术式.作者报告了波士顿市马萨诸塞眼耳医院采用前房角切开这一轻度侵人性手术治疗青少年型开角型青光眼的结果. 相似文献
996.
997.
998.
Jodhbir S Mehta FRCOphth Leonard H Yuen MRCOphth MPH Lakhbir S Mengher DPhil MRCOphth Miltos Papathanassiou MD Bruce DS Allan MD FRCOphth 《Clinical & experimental ophthalmology》2010,38(8):764-767
Background: We evaluate the Visian Implantable Collamer Lens (Staar, Monrovia, CA, USA) phakic intraocular lens for treating post‐keratoplasty anisometropia. Methods: Case series of three eyes (2 phakic and 1 pseudophakic). Results: The mean age was 47.3 years (range 30–73 years), with a minimum of 3‐month follow up. The mean preoperative spherical equivalent was ?8.75 ± 5.17 D (?4.00 to ?14.25 D) improving to ?0.29 ± 1.21 D postoperatively (range 0.75 to ?1.625 D). Mean logMAR uncorrected visual acuity improved from 1.66 ± 0.60 (6/240) preoperatively to 0.41 ± 0.52 (6/152). Mean logMAR best spectacle‐corrected visual acuity improved from 0.32 ± 0.15 (6/12) preoperatively to 0.10 ± 0.11 (6/7.5). Anisometropia improved from a difference of 6.37 ± 2.59 D preoperatively to 2.09 ± 1.37 D postoperatively, and there were no complications. Conclusion: Our technique for this clinical indication shows that the Visian Implantable Collamer Lens is a safe and effective alternative for treating post‐keratoplasty anisometropia. 相似文献
999.
The recent development of [carbonyl-(11)C]WAY-100635 for serotonin (5-HT)(1A) and [(18)F]setoperone and [(18)F]altanserin for 5-HT(2A) positron emission tomography receptor imaging has allowed studies of 5-HT neurotransmission in depressive disorders. The hippocampus is likely to be an important brain structure in the pathophysiology of depression because it may mediate both cognitive deficits and hypercortisolemia found in this disorder. Decreased 5-HT(1A) binding was reported in the medial temporal cortex, which receives dense 5-HT innervation, and also throughout neocortical regions. Because the 5-HT(1A) antagonist pindolol may hasten antidepressant effects of selective serotonin reuptake inhibitor medications, its receptor occupancy has been measured in both presynaptic and postsynaptic sites. The results are controversial but suggest that pindolol has preferential occupancy of somatodendritic autoreceptors in the raphe. The results of 5-HT(2A) receptors are mixed, with one showing a significant decrease in the right orbitoinsular cortex and three not detecting a significant change. The disparate findings in patients with depression almost certainly reflect the heterogeneity of the disorder, and we highlight the utility of the hippocampus as a useful target region not only to compare depressed subjects with healthy subjects but also to correlate findings with cognitive function and activity of the limbic-hypothalamic-pituitary axis system. 相似文献
1000.
A Varrone M Fujita N P Verhoeff S S Zoghbi R M Baldwin N Rajeevan D S Charney J P Seibyl R B Innis 《Journal of nuclear medicine》2000,41(8):1343-1351
This study evaluated the test-retest reproducibility of D2 receptor quantification in the thalamus and temporal cortex using [123I]epidepride SPECT. METHODS: Ten healthy volunteers (4 men, 6 women; age range, 19-46 y) underwent 2 SPECT studies (interval, 2-26 d) using a bolus-plus-constant-infusion paradigm (bolus-to-infusion ratio = 6 h; infusion time = 9 h). Plasma clearance (in liters per hour) and free fraction (f1) of the parent tracer were measured. Radioactivity (in becquerels per gram) in the thalamus, temporal cortex, and cerebellum were normalized to the infusion rate (in becquerels per hour). Normalized striatal radioactivity was also measured to assess reproducibility in regions with a high density of receptors and better counting statistics. The outcome measures obtained were V3 (receptor density [Bmax]/equilibrium dissociation constant [KD]), V3' (f1 x Bmax/KD), and RT (specific-to-nondisplaceable tissue ratio). RESULTS: Test-retest variability and reliability (intraclass correlation coefficient) were 10.8% and 0.88, respectively, for plasma clearance and 15.3% and 0.77, respectively, for f1. The test-retest variability of brain-specific (target minus nondisplaceable) radioactivity was higher in the thalamus and temporal cortex than in the striatum, although reliability was comparable. Among the outcome measures, V3' showed better test-retest variability and reliability in the thalamus (13.3% and 0.75, respectively) and temporal cortex (13.4% and 0.86, respectively). CONCLUSION: Brain radioactivity was the main source of variability for quantification of extrastriatal D2 receptors with [123I]epidepride. The reproducibility of outcome measures in extrastriatal regions was good. However, because receptor density was lower in extrastriatal regions than in the striatum, the counting statistics in these regions were low and reproducibility was affected by the higher test-retest variability of brain-specific radioactivity. Compared with V3 and V3', RT showed less test-retest variability in the thalamus and temporal cortex but lower reliability. Moreover, measurement of RT may be affected by the presence of potential lipophilic metabolites entering the brain. 相似文献