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1.
Abstract Pulpotomy was performed in primary teeth of 4 vervet monkeys to compare the effect of an experimental dressing containing glutaraldehyde (GL) to a similar formula with paraformaldehyde (PF). Forty teeth were examined histologically 2 weeks to 5 months post-operatively. In the PF group, calcifications were more frequently observed and the central core of tissue in the root canal was heavily laden with debris. Pathologic apical resorption and lesions were more frequent. The pulp in the apical third of the root canal was usually uninflamed in the GL group and peripheral calcifications were seldom observed in it. Reaction to GL seemed, therefore, more favorable clinically. Defects were not observed in the permanent teeth that erupted following shedding or extraction of the experimental primary ones of either group.  相似文献   
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The informative value of various lipid indicators and indexes in healthy subjects and in patients with ischaemic heart disease (IHD) is compared. In 10 investigated biochemical indicators significant differences were found between healthy people and subjects with epidemiological or clinical signs of IHD. The first places in the order according to Anderson-Bahadur intervals were held by the cholesterol atherogenity index, total cholesterol (CS) and the percent of high-density lipoproteins cholesterol (HDL-CS) in total CS. The cholesterol atherogenity index and HDL-CS percent in total CS were closely correlated with the severity of angiographically proved changes in the coronary arteries.  相似文献   
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In this report, we show that in the human astroglioma cell line D54-MG, both interleukin-1 (IL-1β) and tumor necrosis factor-alpha (TNF-α) enhance C3 gene expression in a time- and dose-dependent manner. Kinetic analysis demonstrates that after 96 h, C3 mRNA levels increase approximately 30-fold and 20-fold in response to IL-1β or TNF-α, respectively. C3 protein production increases proportionally, reaching levels 36-fold and 18-fold higher than untreated controls upon exposure to IL-1β or TNF-α, respectively. D54-MG cells require a minimal 1 h exposure to IL-1β in order to enhance C3 gene expression significantly, while 4 to 8 h are required for TNF-α. Simultaneous treatment of D54-MG cells with IL-1β and interferon-gamma (IFN-γ) resulted in an additive increase in both C3 mRNA and protein expression, a finding not seen with the combination of TNF-α and IFN-γ. Primary rat astrocytes also express increased C3 mRNA levels after 48 h in response to IL-1β (5.3-fold increase) and TNF-α (7-fold increase), while an additive effect was observed upon simultaneous treatment with both IL-1β and IFN-γ. In the central nervous system (CNS), endogenous complement and cytokine production by astrocytes, and enhancement by IFN-γ, a product of activated T cells often seen in the CNS in neural autoimmune disease, may contribute to the pathogenesis of inflammatory demyelinating diseases such as multiple sclerosis.  相似文献   
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Astrocytes contribute to the immunocompetence of the central nervous system (CNS) via their expression of class II major histocompatibility complex (MHC) antigens and the production of inflammatory cytokines such as interleukin-1 beta (IL-1β), tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6). Of these cytokines, IL-6 is of particular interest because one of its many immune and inflammatory actions is the promotion of immunoglobulin synthesis, and it is thought that IL-6 expression within the brain exacerbates autoimmune diseases of the CNS, which are marked by local immunoglobulin production. Several stimuli induce astrocyte IL-6 expression, including such inducible endogenous factors as IL-1β and TNF-α. We have investigated the possibility that a constitutively present endogenous factor, the neurotransmitter norepinephrine (NE), can induce astrocyte IL-6 production. We report that NE induces both IL-6 mRNA and protein in primary neonatal rat astrocytes, with optimal induction at 10 μM. IL-6 protein induction by NE is comparable to that seen with IL-1β or TNF-α, and NE synergizes with these cytokines for a ten-fold enhanced effect. In contrast to astrocytes, microglia are relatively unresponsive to NE, IL-1β and TNF-α for IL-6 production. Experiments with the β-adrenergic receptor agonist isoproterenol, and α and β-adrenergic receptor antagonists (propranolol, phentolamine, atenolol, and yohimbine) indicate that β2 and α1-adrenergic receptors are involved in NE induction of astrocyte IL-6 expression. These results help to further the understanding of neuron-glial interactions, and the role of astrocytes and adrenergic activity in immune responses within the CNS.  相似文献   
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Reservoirs of latent HIV-1 in T cells and macrophages pose one of the major obstacles that hamper final eradication of HIV-1 from infected patients. Targeting costimulatory molecules expressed on cell types harboring latent HIV-1 to achieve reactivation may provide a new approach to overcome this problem. One such molecule is CD40, a member of the tumor necrosis factor (TNF)-receptor family. Using THP89GFP cells as a model for latently infected macrophages, we demonstrate that trimeric forms of recombinant CD154 allow for the direct reactivation of latent HIV-1 infection. Reactivation is augmented by the release of TNF-alpha. The presence of TNF-alpha is also crucial for the expression of late structural genes such as p24 Gag. In addition, levels of secreted TNF-alpha are sufficiently high to reactivate latent HIV-1 in a latently HIV-1-infected T-cell line (J89GFP). Taken together, our results demonstrate that costimulatory molecules may be attractive targets to reactivate latent HIV-1 in infected patients.  相似文献   
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This research, using focus group methods for data collection, assesses professionals’ perspectives on addressing abuse and neglect among older adults living in rural southwest Virginia. Results were viewed within the context of the family health perspective. The participants identified five major needs encountered in their struggle to provide professional services to address elder abuse and neglect and provided ideas and strategies for addressing these needs. This study highlights the contributions of an interdisciplinary team approach in addressing abuse and neglect among vulnerable older adults. Implications for future research, policy, and practice are discussed.  相似文献   
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The aim of this study was to evaluate the distribution and clinical significance of hepatitis C virus (HCV) genotypes in European patients with compensated cirrhosis due to hepatitis C (Child class A) seen at tertiary referral centres. HCV genotypes were determined by genotype-specific primer PCR in 255 stored serum samples obtained from cirrhotics followed for a median period of 7 years. Inclusion criteria were biopsy-proven cirrhosis, absence of complications of cirrhosis and exclusion of all other potential causes of chronic liver disease. The proportion of patients with types 1b, 2, 3a, 1a, 4 and 5 were 69%, 19%, 6%, 5%, 0.5% and 0.5%, respectively. Kaplan–Meier 5-year risk of hepatocellular carcinoma (HCC) was 6% and 4% for patients infected by type 1b and non-1b, respectively ( P =0.8); the corresponding figures for decompensation were 18% and 7% ( P =0.0009) and for event-free survival were 79% and 89% ( P =0.09), respectively. After adjustment for baseline clinical and serological features, HCV type 1b did not increase the risk for HCC [adjusted relative risk=1.0 (95% confidence interval=0.47–2.34)], whereas it increased the risk for decompensation by a factor of 3 (1.2–7.4) and decreased event-free survival by a factor of 1.7 (0.9–3.10). In conclusion, type 1b and, to a lesser extent, type 2, are the most common HCV genotypes in European patients with cirrhosis. HCV type 1b is not associated with a greater risk for HCC, but increases the risk for decompensation by threefold in patients with cirrhosis.  相似文献   
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