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71.
This study examined the relation between the intensity of CO?-induced psychophysiological responses and content-specific fear conditioning. Sex-balanced groups of undergraduates (N?=?96) were assigned to 1 of 3 conditioned stimuli (CSs) differing in fear-relevance, and within each CS, to either 20% or 13% CO?-enriched air (unconditioned stimuli [UCS]). Several psychophysiological measures were assessed before, during, and following conditioning phases. Consistent with expectation, electrodermal and cardiac conditioned responses were larger and more resistant to extinction when associated with fear-relevant compared with fear-irrelevant stimuli, and this overall effect of fear-relevance was more robust to the more intense UCS. Severity and frequency of DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th ed ) panic symptoms also varied reliably with UCS intensity, and women reported more distress and symptoms than men. Overall, the findings suggest that content-specific fear conditioning is mediated, in part, by the intensity of the bodily response. The authors discuss clinical and theoretical implications for understanding fear onset in the absence of obvious environmental pain or trauma. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
72.
Joachim von zur Gathen 《Computational Complexity》1991,1(4):360-394
Optimal sequential and parallel algorithms for exponentiation in a finite field containing F
q
are presented, assuming thatqth powers can be computed for free. 相似文献
73.
74.
PS Frenette S Subbarao IB Mazo UH von Andrian DD Wagner 《Canadian Metallurgical Quarterly》1998,95(24):14423-14428
The adhesive mechanisms allowing hematopoietic progenitor cells (HPC) homing to the bone marrow (BM) after BM transplantation are poorly understood. We investigated the role of endothelial selectins and vascular cell adhesion molecule-1 (VCAM-1) in this process. Lethally irradiated recipient mice deficient in both P-and E-selectins (P/E-/-), reconstituted with minimal numbers (=5 x 10(4)) of wild-type BM cells, poorly survived the procedure compared with wild-type recipients. Excess mortality in P/E-/- mice, after a lethal dose of irradiation, was likely caused by a defect of HPC homing. Indeed, we observed that the recruitment of HPC to the BM was reduced in P/E-/- animals, either splenectomized or spleen-intact. Homing into the BM of P/E-/- recipient mice was further compromised when a function-blocking VCAM-1 antibody was administered. Circulating HPC, 14 hr after transplantation, were greatly increased in P/E-/- mice treated with anti-VCAM-1 compared with P/E-/- mice treated with just IgG or wild-type mice treated with either anti-VCAM-1 or IgG. Our results indicate that endothelial selectins play an important role in HPC homing to the BM. Optimal recruitment of HPC after lethal doses of irradiation requires the combined action of both selectins and VCAM-1 expressed on endothelium of the BM. 相似文献
75.
AA Bialasiewicz JX Ma U Schandig D von Domarus G Richard 《Canadian Metallurgical Quarterly》1998,213(5):262-270
BACKGROUND: Tumor necrosis may reflect a destructive immune reaction. Systematic and statistically significant comparative clinico-histopathologic studies have not yet been reported. PATIENTS AND METHODS: 113 necrotizing choroidal melanomas (NCM) recruited from 701 enucleated globes 1967-1988 were resectioned, stained and compared to 100 choroidal melanomas without necrosis (CM), and data of 74 patients with a follow-up of more than 10 years were evaluated. RESULTS: Statistically significant characteristics of NCM were: patient age < 60 yrs. for NCM 27.4%, CM 46%; patient age in men for NCM was 64 yrs on average (CM: 58 yrs.), in women for NCM 67 yrs. (CM: 59 yrs.). Time elapsed between first symptoms and enucleation was < 12 months in 15.9% of NCM (89% for CM), and > 12 months in 23.9% of NCM (11% in CM). Mixed or epitheloid cell tumors was seen in 54.9% of NCM and 49% of CM, spindle cell tumors in 36.3% of NCM and 51% in CM. Advanced tumor stages T3 and T4 were present in 45.1% resp. 36.3% of NCM compared to 37% resp. 16% in CM. Scleral invasion was documented in 67.3% of NCM and 37% of CM, extrascleral dissemination in 43% of NCM and 16% of CM. Secondary glaucomas were seen in 62.2% of NCM and 6% CM, a penetration through Bruch's membrane in 61.0% of NCM and 46% of CM. Intratumoral hemorrhage was noted in 68.14% of NCM and 24% of CM, extratumoral bleeding in 23.9% of NCM and 0% CM. Inflammatory reactions in tumors were observed in 96.7% of NCM harboring > 30% necrosis compared to 5% in CM, and extratumoral in 94.5% of NCM and 0% of CM. Intraocular extratumoral necrosis was seen in 23.9% of NCM and 0% of CM. There were no significant differences in the degree of pigmentation of the 90.3% pigmented NCM or of the 94% pigmented CM, neither in the tumor localization, being constantly behind the equator in 87% of cases. Survival of patients with NCM patients was 5 years and 9 months on average (5-year mortality rate 41.9%), and 74.3% were deceased from metastatic spread. CONCLUSIONS: Significant clinical and histopathological differences between necrotizing and non-necrotizing malignant melanomas of the choroid can be identified. The inflammatory reaction of NCM must be further elucidated, particularly with respect to the nature of tumor-infiltrating lymphocytes. 相似文献
76.
Y von Kodolitsch M Raghunath C Dieckmann CA Nienaber 《Canadian Metallurgical Quarterly》1998,87(3):161-172
BACKGROUND: Despite the availability of several different markers for Epstein--Barr virus (EBV) serology, the EBV status of some patients cannot be resolved from a single serum sample with routine testing. To avoid the requirement of follow-up samples, supplementary tests have to be used in these cases. OBJECTIVE: To evaluate the usefulness of avidity and immunoblot assays as supplementary tests for the diagnosis of acute EBV infections. STUDY DESIGN: Three groups of samples for which a definite diagnosis on the EBV status could not be obtained with the routine serological tests were further examined by an EBV IgG avidity assay, by an immunoblot based on a lysate of EBV infected cells, and by a second immunoblot based on recombinant EBV antigens. The three groups consisted of 38 samples with negative/borderline EB nuclear antigen 1 (EBNA-1) antibodies, negative/borderline EBV IgM and positive EBV IgG; 10 samples with indeterminate EBNA-1 and/or EBV IgM assays because of control antigen reactions; and 4 samples with positive EBV IgM results that were not plausible. RESULTS: The avidity assay differentiated between acute and past infections for all samples. In contrast, some cases remained unresolved with both the recombinant and the lysate immunoblot. Two samples were incorrectly classified with the lysate immunoblot. Interpretation of the lysate immunoblot banding patterns was complicated when anticellular antibodies were present. CONCLUSION: Avidity testing appears to be the confirmatory method of choice to differentiate between acute and past EBV infections. 相似文献
77.
M Thiel C Zourelidis JD Chambers UH von Andrian KE Arfors K Messmer K Peter 《Canadian Metallurgical Quarterly》1997,29(3):160-175
Adhesion molecules on polymorphonuclear leukocytes (PMNL) play an important role in nonspecific defense mechanisms directed at invading microorganisms. When local infection, however, cannot be controlled, a systemic inflammatory response syndrome (SIRS) ensues which may progress to septic shock and multiple organ failure, these being major determinants of the patient's outcome. In the present study, the expression of beta 2-integrins and L-selectin on blood PMNL was measured on subsequent days in patients with sepsis (n = 17) and in healthy volunteers (n = 15). beta 2-Integrins and L-selectin molecules were detected by flow cytometry, using the monoclonal antibodies IB4 (anti-CD18) and Dreg200 (anti-CD62L), respectively. Adhesion molecules were determined at baseline immediately after blood collection and also 45 min after incubation of cells in vitro at body temperature to allow for spontaneous regulation. In addition, PMNL were activated by receptor-dependent and receptor-independent stimuli to characterize stimulus-specific adhesion molecule expression. In parallel with the measurement of adhesion molecules, severity of sepsis was assessed by the Elebute score. The results demonstrate significant differences in the basal, spontaneous and stimulus-induced expression of adhesion molecules between healthy volunteers, survivors (n = 11) and nonsurvivors (n = 6). Moreover, when survivors and nonsurvivors with severe sepsis (Elebute score > 12) were compared, basal expressions of both beta 2-integrins and L-selectin were significantly lower in patients who did not survive. Thus, measurement of adhesion molecules on circulating PMNL may be useful to identify septic patients at high risk for lethal outcome. 相似文献
78.
Andreas Klenk Andreas Beck-Greinwald Hannes Angst Georg Carle 《Service Oriented Computing and Applications》2012,6(4):321-335
Inter-domain collaborations suffer not only from technological obstacles that hinder interoperability, but also from diverting business objectives of the involved domains. Today, hand-crafted contracts define the terms and conditions for service interactions. Electronic negotiation can serve as the enabler of dynamic interdomain collaborations by providing a large degree of freedom for the automation of agreement formation and electronic contracting. Negotiation by electronic means has been an area of intensive research for many years now. However, most effort was put on the determination of prices and neglected that real-world agreements also consist of complex dependencies of interdependent obligations. In this paper we present agreement negotiation as a tool to establish ad hoc services collaborations. Our novel protocol allows for the discovery of complex agreement options and for the formation of multi-party agreements. The protocol works through an iterative exchange of requirements and offers. A major benefit over existing bilateral negotiation protocols is that our protocol is capable of discovering potential collaborations between different parties. It will leave each negotiating party with a complete agreement document after a successful negotiation. This comprehensive agreement document defines the interdependent obligations between all parties and is well suited for E-Contracting. 相似文献
79.
80.
The examination of the solidification behaviour and resultant microstructures in an Al-Li-Cu-Mg-Zr alloy processed by high-pressure inert gas atomization is reported. Using analytical transmission electron microscopy some quantification of the segregation behaviour is possible which allows the comparison with a simple solute redistribution model (Scheil analysis). It is shown that for powder sizes likely to be of commercial interest (10 to 20 m), cellular solidification structures are to be expected on atomization, and methods of utilizing such structures are discussed. 相似文献