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41.
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NP Ching J Lumeng R Pang G Pang FW Or NW Ching C Ching 《Canadian Metallurgical Quarterly》1998,57(12):735-739
The antiviral and immunomodulatory effects of interferon were assessed in the treatment of chronic Hepatitis C in multi-ethnic patients to prevent viral replication and chronic liver damage. Three million units of recombinant interferon alpha-2b were administered three times a week for 48 weeks to a group of 9 active Hepatitis C patients. A clinical response was defined as normalization of serum ALT values. Serum was frozen and stored for Hepatitis C viral assays. Four patients normalized their liver functions. When viral levels were measured only two patients had unmeasurable levels of HCV RNA after treatment. Therapeutic results were observed and much work needs to be done to improve therapy because a serious epidemic is predicted for the future. 相似文献
43.
Child welfare practice and substance abuse treatment have become overlapping areas for many human service professionals. This article stresses the importance of combining perspectives, calling for the child welfare and alcohol and other drug (AOD) abuse treatment systems to deal with both the mother's recovery and the child's well-being. Changes in attitudes, knowledge, and skills are required on the part of both the child welfare practitioner and the AOD abuse treatment worker. 相似文献
44.
BACKGROUND: The Women and Infants Transmission Study is an ongoing prospective cohort study of HIV-infected pregnant women and their infants. We used the 1994 U.S. Centers for Disease Control and Prevention (CDC) classification system for HIV infection in children to describe HIV disease progression in 128 HIV-infected children, and examined maternal and infant characteristics associated with disease course. METHODS: The Kaplan-Meier method was used to calculate probabilities of entry into CDC clinical classes A, B, and C (mild, moderate, and severe HIV disease); CDC immunologic stages 2 and 3; and death. Relative risks of progression for selected predictor events were estimated using the Cox proportional hazards model. RESULTS: With a median 24 months of follow-up, the median ages at entry into clinical classes A, B and C were 5, 11, and 48 months, respectively. Increased risk of progression to class C was seen in infants who had: onset of class B events (p < .001); progression to immunologic stage 2 (p < .001) or 3 (p < .001); early culture positivity (in first 48 hours, p < .01; in first 7 days, p = .03); and early appearance (within the first 3 months of life) of lymphadenopathy, hepatomegaly, or splenomegaly (p < .001). CONCLUSIONS: Reaching specific clinical or immunologic stages were strong predictors of progression to AIDS or death. Early onset of clinical signs (onset of lymphadenopathy, hepatomegaly, or splenomegaly < or =3 months of age), and early culture positivity (within the first 48 hours or within the first week of life), defined the infant with highest risk of disease progression. 相似文献
45.
EV Caler S Vaena de Avalos PA Haynes NW Andrews BA Burleigh 《Canadian Metallurgical Quarterly》1998,17(17):4975-4986
Mammalian cell invasion by the intracellular protozoan parasite Trypanosoma cruzi is mediated by recruitment and fusion of host cell lysosomes, an unusual process that has been proposed to be dependent on the ability of parasites to trigger intracellular free calcium concentration ([Ca2+]i) transients in host cells. Previous work implicated the T.cruzi serine hydrolase oligopeptidase B in the generation of Ca2+-signaling activity in parasite extracts. Here we show that deletion of the gene encoding oligopeptidase B results in a marked defect in host cell invasion and in the establishment of infections in mice. The invasion defect is associated with the inability of oligopeptidase B null mutant trypomastigotes to mobilize Ca2+ from thapsigargin-sensitive stores in mammalian cells. Exogenous recombinant oligopeptidase B reconstitutes the oligopeptidase B-dependent Ca2+ signaling activity in null mutant parasite extracts, demonstrating that this enzyme is responsible for the generation of a signaling agonist for mammalian cells. 相似文献
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WJ Karpus NW Lukacs BL McRae RM Strieter SL Kunkel SD Miller 《Canadian Metallurgical Quarterly》1995,155(10):5003-5010
Experimental autoimmune encephalomyelitis (EAE) is a CD4+ T cell-mediated, inflammatory demyelinating disease of the central nervous system (CNS) that serves as a model for the human demyelinating disease, multiple sclerosis. A critical event in the pathogenesis of EAE is the entry of both Ag-specific T lymphocytes and Ag-nonspecific mononuclear cells into the CNS. In the present report we investigated the role of two C-C chemokines (macrophage inflammatory protein-1 alpha (MIP-1 alpha) and monocyte chemotactic protein-1) and a C-x-C chemokine (MIP-2) in the pathogenesis of EAE. Production in the CNS of MIP-1 alpha, but not that of MIP-2, a rodent homologue of IL-8, or monocyte chemotactic protein-1, correlated with development of severe clinical disease. Administration of anti-MIP-1 alpha, but not that of anti-monocyte chemotactic protein-1, prevented the development of both acute and relapsing paralytic disease as well as infiltration of mononuclear cells into the CNS initiated by the transfer of neuroantigen peptide-activated T cells. Ab therapy could also be used to ameliorate the severity of ongoing clinical disease. Anti-MIP-1 alpha did not affect the activation of encepahlitogenic T cells as measured by cytokine secretion, surface marker expression, and ability to adoptively transfer EAE. These results demonstrate that MIP-1 alpha plays an important role in directing the chemoattraction of mononuclear inflammatory cells in the T cell-mediated autoimmune disease, EAE. 相似文献
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49.
Peptides labelled with the fluorophore cyanine 3 were used to study naturally expressed neuropeptide receptors by confocal microscopy in continuous cell lines, primary cultures, and unfixed tissue. Swiss 3T3 fibroblasts bound cyanine 3-gastrin-releasing peptide at 4 degrees C, and internalized the peptide after 10 min at 37 degrees C. Internalization was specific, since it was blocked by incubation with unlabelled peptide. Primary cultures of myenteric neurons of the guinea pig incubated with cyanine 3-substance P at 4 degrees C had specific surface labelling. After 30 s at 37 degrees C, the peptide was internalized into vesicles in both the soma and neurites. Direct observation of live neurons showed movement of fluorescent vesicles to a perinuclear region after 30 min. Endocytosis was associated with a loss of surface binding sites. Unfixed whole mounts of guinea pig and rat ileum were incubated with cyanine 3-neurokinin A at 4 degrees C. After 5 min at 37 degrees C, Cy3-neurokinin A was specifically internalized in neurons and smooth muscle cells. After 30 min, a perinuclear labelling occurred in some cells. Labelling in rat neurons was diminished by the NK3-R antagonist SR142801. Thus, cyanine 3-neuropeptides are valuable tools to study expression and endocytosis of naturally expressed receptors. 相似文献
50.
The study was to examine the applicability of the screening test for the Luria-Nebraska Neuropsychological Battery in Taiwan. This screening test contains 15 items. It could be used at the first stage of neuropsychological assessment process and served as a screening tool for brain-damaged patients. In this study, 50 brain-damaged patients, 50 normal controls receiving physical examination, and 100 normal controls from local communities were sampled and administered with the screening test. Based on test results, item analysis and factor analysis were performed, reliability and validity data were established, and temporary local norm and subgroup norm were also developed. It also investigated the effects of age and educational level on test performance. Further factor analysis with total subjects showed that three factors were extracted. Factor 1 was number concept and simple calculation. Factor 2 was higher cortical function. Factor 3 was motor control and rhythm. These three factors accounted for sixty percent of total variance. In addition, cut-off scores were set for low and high education groups. 相似文献