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Hypersensitivity reactions occurring during barium studies of the gastrointestinal tract are rare. A case is presented with radiographically demonstrated angioedema in the stomach and small bowel accompanied by allergic rhinitis, which was apparently an allergic response to the barium sulfate suspension. The reaction was documented twice during separate challenges to the barium suspension performed several months apart.  相似文献   
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Inhibition by prostaglandin E1 (PGE1) of superoxide anion (O2-.) production by isolated intact human neutrophils (PMNs) was investigated utilizing initial-velocity enzyme kinetics. Lag time, linearity, rate, and extent of reaction were simultaneously examined. Dose-response data indicate progressive PGE1-induced suppression of O2-. synthesis by activated PMNs with a Ki value of 0.50 and 0.98 mumol/L for initial velocity and extent of reaction, respectively. There were no significant dose-related trends for either lag time or linearity for reactions with PGE1 concentrations less than 10(-6) mol/L; however, at concentrations of 10(-8) mol/L and greater, the length of reaction was progressively shortened. PGE1 inhibition of PMN-induced O2-. production does not involve PMN activation/desensitization since PGE1 itself cannot stimulate O2-. generation. Moreover, PGE1 does not function as a free-radical scavenger. These data indicate the clinical feasibility of utilizing PGE1 to titrate PMN-induced synthesis of active oxygen metabolites, in order to attenuate PMN-associated host autoinjury.  相似文献   
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The three most widely used diagnostic systems in American psychiatry--the Feighner criteria, the Research Diagnostic Criteria, and DSM-III--appeared sequentially at 4-year intervals. The fact that the latter two systems each incorporated changes in essentially all diagnostic categories implied progress toward greater validity; however, this assumption has rarely been tested directly. To do this, the authors applied each of these three systems to 98 consecutively admitted patients with nonmanic psychoses. Although family history and 6-month follow-up data strongly supported the validity of diagnostic distinctions made in each of the three systems, they did not show increments in validity with successively developed criteria sets.  相似文献   
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Nancy Kluck, Scan J. O'Connor, Victor M. Hesselbrock, Allan Tasman and Donald Maier, Lance Bauer: Variation in Evoked Potential Measures Over the Menstrual Cycle: A Pilot Study. Prog. Neuro. Psychopharmacol. Biol. Psychiat. 1992. 16(6): 901–911.

1. 1. The P3 component of a visual event related potential (ERP) was studied for five consecutive weeks in six women with normal menstrual cycles. Serum concentrations of luteinizing hormone (LH), estradiol (E2) and progesterone were studied during the same period.

2. 2. Increases in P3 amplitude, although nonsignificant, were noted in the week preceding onset of menses.

3. 3. No significant changes in reaction times to target/nontarget stimuli were noted over the same time period.

Author Keywords: Event-related potentials; females; menstrual cycle  相似文献   

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Heroin use is postulated to act as a cofactor in the neuropathogenesis of human immunodeficiency virus (HIV-1) infection. Astrocytes, integral components of the CNS, are reported to be susceptible to HIV-1 infection. Upon activation, astrocytes release a number of immunoregulatory products or modulate the expression of a number of proteins that foster the immunopathogenesis of HIV-1 infection. However, the role of heroin on HIV-1 infectivity and the expression of the proteome of normal human astrocytes (NHA) have not been elucidated. We hypothesize that heroin modulates the expression of a number of proteins by NHA that foster the neuoropathogenesis of HIV-1 infection. We utilized LTR amplification and the p24 antigen assay to quantitate the effect of heroin on HIV-1 infectivity while difference gel electrophoresis (DIGE) combined with protein identification through high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to analyze the effects of heroin on the proteomic profile of NHA. Results demonstrate that heroin potentiates HIV-1 replication in NHA. Furthermore, heroin significantly increased protein expression levels for protein kinase C (PKC), reticulocalbin 1 precursor, reticulocalbin 1, tyrosine 3-monooxgenase/tryptophan 5-monooxgenase activation protein, chloride intracellular channel 1, cathepsin D preproprotein, galectin 1 and myosin light chain alkali. Heroin also significantly decreased protein expression for proliferating cell nuclear antigen, proteasome beta 6 subunit, tropomyosin 3, laminin receptor 1, tubulin alpha 6, vimentin, EF hand domain family member D2, Tumor protein D54 (hD54), ATP synthase, H+ transporting, mitochondrial F1 complex and ribosomal protein S14. Identification of unique, heroin-induced proteins may help to develop novel markers for diagnostic, preventative and therapeutic targeting in heroin using subjects.  相似文献   
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