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81.
Peter L. Forster Frank B. Schoenfeld Charles R. Marmar Ariel Janna Lang 《Journal of traumatic stress》1995,8(1):143-149
Irritability is often a problem for patients with Post-Traumatic Stress Disorder (PTSD). We describe two cases that illustrate the use of lithium in the treatment of veterans with PTSD who complained of serious problems with irritability or angry outbursts. These cases are discussed in the context of evidence that lithium may be useful in other patients with disorders of impulse control. The evidence linking disorders of anger and impulse control to a dysregulation in neurotransmitter regulation, particularly in serotonergic pathways, supports a psychopharmacologic approach to treatment. These findings should lead to further study of the role of lithium in the treatment of this symptom complex in patients with PTSD. 相似文献
82.
P. J. Foreman G. Taglialatela L. Angelucci C. P. Turner J. R. Perez-Polo 《Journal of neuroscience research》1993,36(1):10-18
The synthesis of nerve growth factor (NGF) by the hippocampus raises the possibility that NGF may play a role in the regulation of the hypothalamic-pituitary-adrenal axis (HPAA). Subchronic cold stress has been shown to activate the HPAA in a mild noninvasive manner, to stimulate serum glucocorticoid levels, and to perturb NGF binding in hippocampus and basal forebrain. One or repeated episodes of cold stress increased NGF mRNA levels in the hippocampus and p75NGFR mRNA levels in the basal forebrain. These changes were not due to elevated serum glucocorticoid levels since treatment with exogenous corticosterone had no effect on NGF and p75NGFR mRNA levels. Adrenalectomy did not prevent the stress induced increases in NGF and p75NGFR mRNA. © 1993 Wiley-Liss, Inc. 相似文献
83.
Itiswellknownthatcertaincytokinesplayapivotalroleinthedevelopmentoftraumaandshock.Tumornecrosisfactor(TNF)isapolypep-tiedcytokinesynthesizedinmonocytesandmacrophagesinresponsetolipopolysaccharide(LPS)stimulation-TherelationshipbetweenTNFandendotoxic-septicshockbecomesafocusoftheresearchofshockmediators[1'2].Alargeamountofexperimentalandclinicaldata[3-9JsuggestthatTNFplaysanimportantroleinthepathogenesisofendotoxic-septicshockbuttheprecisemechanismandtherelationshipofTNFtoshockseverityrem… 相似文献
84.
A comprehensive and reliable assessment of work stress, burnout, affective, and physical symptomatology was conducted with 260 hospital nurses. As previous attempts to categorize nursing stress and burnout by ward type have yielded inconsistent results, an alternative method for grouping nursing stress effects was sought. Cluster analysis was chosen as it offers a statistically sound means of delineating natural groupings within data. Sets of questionnaires measuring burnout, work stressors, and physical and emotional symptomatology were sent to all staff nurses at a large university hospital. Of 709 nurses employed there, a total of 260 nurses returned completed questionnaire packets. These nurses were separated into two equal groups using random sampling procedures. Cluster analysis of this data revealed groupings which were based on nursing stressors (particularly workload and conflict with physicians), social support, and patient loads. These cluster-analytic findings were replicated on both samples, and validated using data not used in the original cluster analysis. Results suggest that the effects of stress have more to do with the characteristics of the work environment and overall workload than with the degree of specialization on the unit. Results also suggest that intraprofessional conflict (i.e. with other nurses) is less psychologically damaging than is interprofessional conflict (i.e. conflict with physicians). Findings are discussed with respect to the burnout process and possible interventions. 相似文献
85.
86.
Nakamura Hajime; De Rosa Stephen; Roederer Mario; Anderson Michael T.; Dubs J. Gregson; Yodoi Junji; Holmgren Arne; Herzenberg Leonard A.; Herzenberg Leonore A. 《International immunology》1996,8(4):603-611
Thioredoxin (Trx), a ubiquitous protein intimately involvedin redox and protein disulfide reductions, has been shown tobe released from cells and to have cytokine-like activities.In addition, Trx has been implicated in the redox regulationof immunological responses and shown to be deficient in tissuesfrom AIDS patients. In studies presented here, plasma Trx levelswere measured by ELISA in plasma samples from HIV-infected individuals(n = 136) and HIV-negative controls (n = 47). To account forthe release of Trx into plasma due to hemolysis, the Trx measurementswere corrected according to the level of hemoglobin in the plasmasample. Data presented show that, in contrast to tissue Trxlevels, corrected plasma Trx levels are significantly higherin HIV-infected individuals than in controls (P < 0.0001).Furthermore, {small tilde}25% of the HIV-infected individualsstudied have plasma Trx levels greater than the highest levelfound in controls (37 ng/ml). Detailed multiparameter FACS analysisof peripheral blood mononuclear cells (PBMC) from the infectedindividuals demonstrates that those with higher plasma Trx levels(37 ng/ml or greater) tend to have lower overall CD4 counts.In addition, increases in plasma Trx levels correlate with decreasesin monochlorobimane staining (indicative of lower intracellularglutathione levels in PBMC) and with changes in surface antigenexpression (CD62L, CD38 and CD20) that occur in the later stagesof HIV infection. These correlations suggest that elevationof plasma Trx levels may be an important component of advancedHIV disease, perhaps related to the oxidative stress that oftenoccurs at this stage. 相似文献
87.
B. Leveugle B. A. Faucheux C. Bouras N. Nillesse G. Spik E. C. Hirsch Y. Agid P. R. Hof 《Acta neuropathologica》1996,91(6):566-572
Changes in the distribution of the iron-binding protein lactotransferrin have recently been described in the central nervous
system during a variety of neurodegenerative disorders. To investigate whether lactotransferrin is associated with the neuropathological
changes that characterize Parkinson’s disease, we analyzed the distribution of this protein in the mesencephalon of neurologically
normal individuals and patients affected with Parkinson’s disease using quantitative immunohistochemical methods. High levels
of lactotransferrin were observed in a large population of neurons in the substantia nigra of control cases. Lactotransferrin-positive
neurons were severely affected by the neurodegenerative process that occurs in Parkinson’s disease as indicated by a severe
decrease in the number of immunolabeled neurons in all of these cases. Quantitative analysis also demonstrated higher immunolabeling
levels of lactotransferrin in the surviving neurons in the substantia nigra and ventral tegmental area of Parkinson’s disease
cases compared to control cases. These results suggest that lactotransferrin may participate actively in the mechanism of
neuronal degeneration in Parkinson’s disease.
Received: 16 October 1995 / Revised, accepted: 1 December 1995 相似文献
88.
Martin Tepel 《Nephrology, dialysis, transplantation》2003,18(8):1439-1442
Reactive oxygen species: general aspects Reactive oxygen species, including superoxide radicals, hydrogenperoxide, nitric oxide, peroxynitrite, hydroxyl radicals andhypochlorous acid are by-products of normal metabolic processesin cells. Reactive oxygen species can be found in several cellsincluding macrophages and vascular smooth muscle cells. At lowconcentrations reactive oxygen species can act as physiologicalmediators of cellular responses whereas higher concentrationsmay cause cell damage [1,2]. The major sources of reactive oxygenspecies are leakages from the electron transport chains of mitochondriaand endoplasmic reticulum. Cellular energy metabolism is basedon the production of ATP through the electron transport reactionin which O2 accepts electrons and H+ and then is eventuallyreduced to water. Only 12% of the electrons are leakedto generate superoxide radicals in reactions mediated by coenzymeQ and ubiquinone and its complexes. During ageing (and probablyin patients 相似文献
89.
Effect of dialysis flux and membrane material on dyslipidaemia and inflammation in haemodialysis patients. 总被引:4,自引:0,他引:4
Christoph Wanner Udo Bahner Renate Mattern Dietmar Lang Jutta Passlick-Deetjen 《Nephrology, dialysis, transplantation》2004,19(10):2570-2575
BACKGROUND: Dyslipidaemia, inflammation and oxidative stress are prominent risk factors that potentially cause vascular disease in haemodialysis patients. Dialysis modalities affect uraemic dyslipidaemia, possibly by modifying oxidative stress, but the effects of dialyser flux and membrane material on atherogenic remnant particles and oxidized low-density lipoproteins (LDL) are unknown. METHODS: We performed a randomized crossover study in 36 patients on haemodialysis to analyse the effect of dialyser flux and membrane material on plasma lipids, apolipoproteins and markers of inflammation and oxidative stress. Stable patients on low-flux dialysis with polysulphone for >/=6 weeks were assigned to high-flux polysulphone or high-flux modified cellulose with similar dialyser surface area and permeability characteristics and crossed over twice every 6 weeks. RESULTS: Thirty patients completed the study per protocol. Treatments with high-flux polysulphone and modified cellulose lowered serum triglyceride (by 20% and 10%, respectively; P<0.05) and remnant-like particle cholesterol by 32% (P<0.001) and 11% (NS) after the first 6 weeks of treatment. Oxidized LDL decreased significantly with high-flux polysulphone, but not with modified cellulose. Apolipoproteins CII and CIII were reduced, whereas the ratio CII/CIII was increased (all P<0.05). Acute-phase proteins and LDL and high-density lipoprotein cholesterol remained unaffected. CONCLUSIONS: This randomized crossover study demonstrates a potent effect of high-flux haemodialysis on uraemic dyslipidaemia. Polysulphone membrane material showed superiority on oxidatively modified LDL, an indicator of oxidative stress in haemodialysis patients. 相似文献
90.
Objective To evaluate the use of the saphenous artery as an alternative access for endovascular procedures in the porcine model. Methods Fourteen adult pigs (25-35kg) were used in this study, 3 pigs from an acute study and 11 from chronic studies. A 2-3 cm incision was made and a saphenous artery cutdown was performed in 24 sides. Micropunc ture sets (Boston Scientific) or 18 G puncture needles were used to access the artery. Different sizes of introducers (4-7F) were used to establish endovascular access. Angiographic catheters were then used to confirm if the access was usable. Four saphenous arteries were explanted in the pigs from a chronic study 4 to 28 days after surgical procedure. Results The saphenous artery was very easy to expose and 4-5 F introducer sheaths were able to be inserted to establish access for endovascular procedures in the pigs. The saphenous artery was unable to accomodate an introducer with a size larger than 6 F. Four saphenous arteries were injured when 5 and 6 F introducers were used, but angiographic procedures could still be performed. Morphologic evaluation of the explanted arteries demonstrated occlusion of the saphenous arteries without injury or disruption of the adjacent femoral arteries. Conclusion The saphenous artery can be used as an access site in pigs for angiographic and interventional procedures if the catheter size is less than 6 F. This vessel is easier to access and can preserve the femoral artery for repeat procedures in the future. 相似文献