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81.
The article by Richard J. Longmore and Michael Worrell [Clinical Psychology Review, Volume 27, 2007, pp. 173–187] reviews a selection of studies showing no significant difference between treatment conditions that include formal cognitive restructuring techniques and other behavioral treatment modalities that do not include techniques to directly challenge cognitions. Based on this literature, Longmore and Worrell question the validity of the cognitive behavioral treatment model and argue that changes in symptoms are not mediated by changes in cognitions. Longmore and Worrell's arguments are based on common misconceptions about mediation models of treatment change. This commentary discusses and clarifies these misconceptions.  相似文献   
82.
Aspartylglucosaminuria in the United States   总被引:2,自引:0,他引:2  
Aspartylglucosaminuria (AGU) was diagnosed in two unrelated males with progressive mental retardation, coarse facies and skeletal abnormalities. Until now, this disorder has been described in predominantly Finnish populations with only one previous case reported in the U.S. We conclude that AGU may be more common in nowFinnish populations than the number of reported cases would indicate and should be included in the differential diagnosis in patients with suspected lysosomal storage disorders regardless of their geographical or ethnic backgrounds.  相似文献   
83.
INTRODUCTION: Researchers and clinicians have increasingly recognized that biological markers may help identify patients who are at risk for suicide. The objective of this retrospective, cross-sectional study was to compare the prevalence and location of white matter hyperintensities (WMH) in young inpatients with major depressive disorder (MDD) with and without histories of suicide attempts. METHODS: T2-weighted magnetic resonance images (MRI) of 102 young psychiatric inpatients with MDD were rated for the presence of WMH. Medical charts were reviewed to ascertain history of suicide attempt, demographic and clinical variables. Fisher's Exact Tests and logistic regression modeling were used to test the association between WMH and suicidality. RESULTS: Bivariate analysis showed that the prevalence of periventricular WMH was significantly higher in subjects with past suicide attempts (Fisher's Exact Test, p=0.02). Logistic regression analyses controlling for age, sex, and several clinical risk factors supported this finding (odds ratio=5.7; 95% confidence interval: 1.6, 21.2). LIMITATIONS: Due to the retrospective, cross-sectional design of our study, we are unable to determine if the WMH preceded or followed past suicide attempts. The generalizability of our findings is limited since this group of inpatients is more severely ill than the general psychiatric population. CONCLUSIONS: The increased prevalence of periventricular WMH in young adults with MDD and a history of suicide attempt, compared to similarly depressed adults without such a history, is consistent with our findings in children and youth, and suggests there might be neurobiological in addition to psychosocial risk factors for suicide.  相似文献   
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BACKGROUND: Binding of allergens with IgE to the IgE receptors on mast cells and basophils results in the release of inflammatory mediators as sulfidoleukotrienes (SLTs), triggering allergic cascades that result in allergic symptoms, such as asthma and rhinitis. OBJECTIVE: We sought to investigate whether anti-IgE (Oma-lizumab), a humanized monoclonal anti-IgE antibody, in addition to specific immunotherapy (SIT) affects the leukotriene pathway. METHODS: Ninety-two children (age range, 6-17 years) with sensitization to birch and grass pollens and with seasonal allergic rhinitis were included in a phase III, placebo- controlled, multicenter clinical study. All subjects were randomized to one of 4 treatment groups. Two groups subcutaneously received birch SIT and 2 groups received grass SIT for at least 14 weeks before the start of the birch pollen season. After 12 weeks of SIT titration, placebo or anti-IgE was added for 24 weeks. The primary clinical efficacy variable was symptom load (ie, the sum of daily symptom severity score and rescue medication score during pollen season). Blood samples taken at baseline and at the end of study treatment after the grass pollen season were used for separation of leukocytes in this substudy. After in vitro stimulation of the blood cells with grass and birch pollen allergens, SLT release (LTC4, LTD4, and LTE4) was quantified by using the ELISA technique. RESULTS: Before the study treatment, SLT release to birch and grass pollen exposure did not differ significantly among the 4 groups. Under treatment with anti-IgE + SIT-grass (n = 23), a lower symptom load occurred during the pollen season compared to placebo + SIT-grass (n = 24, P =.012). The same applied to both groups receiving birch SIT (n = 23 and n = 22, respectively; P =.03). At the end of treatment, the combination of anti-IgE plus grass SIT, as well as anti-IgE plus birch SIT, resulted in significantly lower SLT release after stimulation with the corresponding allergen (416 ng/L [5th-95th percentile, 1-1168] and 207 ng/L [1-860 ng/L], respectively) compared with placebo plus SIT (2490 ng/L [384-6587 ng/L], P =.001; 2489 ng/L [1-5670 ng/L], P =.001). In addition, treatment with anti-IgE was also followed by significantly lower SLT releases to the allergens unrelated to SIT (grass SIT: 300 ng/L [1-2432 ng/L] in response to birch allergen; birch SIT: 1478 ng/L [1-4593 ng/L] in response to grass pollen) in comparison with placebo (grass SIT: 1850 ng/L [1-5499 ng/L], P =.001; birch SIT: 2792 ng/L [154-5839 ng/L], P =.04]. CONCLUSION: Anti-IgE therapy reduces leukotriene release of peripheral leukocytes stimulated with allergen in children with allergic rhinitis undergoing allergen immunotherapy independent of the type of SIT allergen used.  相似文献   
86.
Fibrin as a cell carrier in cardiovascular tissue engineering applications   总被引:10,自引:0,他引:10  
In cardiovascular tissue engineering approaches, efficient seeding methods are essential. To achieve this and to save time, cells can be encapsulated in gels. Combining the advantages of a gel as a cell carrier with the advantages of a fiber-based scaffold, providing structural integrity to the developing tissue, might offer several advantages. In this study, seeding by using fibrin as a cell carrier is compared to the conventional static seeding method with regard to tissue development. Seeding with fibrin resulted in less loss of soluble collagen into the medium and a more mature extracellular matrix in a shorter period of time. The use of fibrin degradation inhibitors was shown to inhibit extracellular matrix formation, although it did not hamper cell proliferation. The use of fibrin as a cell carrier to seed cells into a fiber-based scaffold may represent a promising, timesaving approach in cardiovascular tissue engineering applications.  相似文献   
87.
BACKGROUND: In contrast to aggressive mastocytosis, patients with indolent systemic mastocytosis (ISM) usually present with urticaria pigmentosa-like skin lesions. In those who lack skin lesions, mastocytosis is often overlooked or confused with endocrinologic, allergic, or other internal disorders. CASE REPORT AND RESULTS: We report on a 33-year-old male patient in whom severe hypotensive episodes occurred after contact with ants or yellow jackets. Since no specific IgE was detected, the serum tryptase concentration was measured and found to be clearly elevated (70 ng/ml). Consecutive staging and examination of the bone marrow revealed ISM. The patient was advised to circumvent insect contact, to take antihistamines on demand, and to carry an epinephrine self-injector for emergency events. In a retrospective analysis of 40 patients seen between 1988 and 2003, only 2 had a life-threatening mediator-related episode before ISM was diagnosed. CONCLUSIONS: Our report confirms the diagnostic value of tryptase in patients with suspected mastocytosis. In addition, the report suggests that the lack of typical skin lesions does not exclude an indolent form of mastocytosis even if the serum tryptase is clearly elevated. Finally, our case further shows that mastocytosis can be an important differential diagnosis to be considered in patients with unexplained anaphylactoid or other mediator-related symptoms.  相似文献   
88.
89.
Self-injurious behavior (SIB) and aggression have been linked to reduced serotonergic (5-HT) functioning in both humans and nonhuman primates. The present study examined serum prolactin and cortisol responses to the 5-HT releasing agent D,L-fenfluramine (FEN) in 24 individually housed rhesus monkeys (Macaca mulatta), 15 of which carried a veterinary record of self-wounding (SW). Subjects received two doses of FEN, 4 and 2 mg/kg, separated by an interval of at least 2 months. For control purposes, monkeys were given an intramuscular saline injection 1 week prior to each FEN challenge. The relationship between the hormonal responses to FEN, wounding history, the rates of self-directed biting and aggression were determined for each animal based on 100 five-minute observations conducted over a period of 12 months surrounding the challenge procedures. Prolactin and cortisol responses to FEN were unrelated either to wounding history or to rates of self-directed biting. However, there were significant inverse correlations between levels of aggression and the prolactin response to both doses of FEN. The present findings provide no evidence for reduced 5-HT system function in rhesus monkeys with SIB under the present challenge conditions. However, the results are consistent with a previously reported inverse relationship between serotonergic activity and aggression. Moreover, a dose-dependent response to FEN was observed only for prolactin, suggesting that this variable is more appropriate than cortisol as an endpoint for FEN challenge in monkeys.  相似文献   
90.
Acquired resistance against tuberculosis paradigmatically depends on specific T lymphocytes and mononuclear phagocytes. The etiological agent,Mycobacterium tuberculosis is capable of replicating in mononuclear phagocytes which act both as habitat and as effectors of protection. Upon interaction with antigen-specific T lymphocytes infected mononuclear phagocytes acquire tuberculosis activities. Here, data from experimental tuberculosis studies in mice are summarized which show that: interleukins produced by cloned T cells and recombinant interferon-γ are capable of activating tuberculostatic capacities in macrophages; both CD4 and CD8 T cells, after adequate stimulation, produce interferon-γ; CD8 T cells lyse macrophages in an antigen-specific way; not only CD8 but also CD4 T cells possess an antigen-specific cytolytic potential; lysis of infected macrophages results in mycobacterial growth inhibition. Evidence is also presented that tuberculostatic activities of activated macrophages depend on phagosome-lysosome fusion and are independent of reactive oxygen metabolites and that some strains ofM. tuberculosis are resistant against interferon-γ activated macrophages. These findings suggest that both helper and cytolytic T cells participate in the immune response to tuberculosis and that similar T cell mechanisms contribute to resistance as well as pathogenesis. Protection against tuberculosis, therefore, depends on subtle coordination of the immune response.  相似文献   
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