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991.
The duration from initial infection with HIV-1 to CD4 lymphocyte depletion and progression to AIDS varies among infected individuals. Despite treatment with highly active antiretroviral therapy (HAART), patients still show different stages of disease progression. We examined the role of beta-chemokines and its receptor, CCR5 in HIV-1 infected children in order to define determinants of HIV progression among treated individuals. Population was divided in two groups: Group 1--Long Term Non Progressors (LTNP) includes 10 patients with B1-B2 CDC disease classification and with a less aggressive therapy (only 2 in HAART); Group 2--Rapid Progressors (RP) includes 9 patients with C3 disease classification. All the patients had a CCR5 wild type (wt) genotype indicating that they do not have the 32 base-pair deletion associated with slower progression. There was an increased production of MIP 1-beta in 8/10 LTNP but only in 4/9 Progressors (Paired t-test/Wilcoxon Sign test, p-value < 0.05). The change in the levels of MIP-1 beta after PHA stimulation was statistically significant in both groups. The levels of RANTES increased in LTNP and RP and the change of the levels after mitogen stimulation was statistically significant for both groups included. The production of RANTES and MIP-1 beta in response to stimulation between both groups was not statistically significant. The production of MIP-1 alpha was variable in both groups and the difference in the levels after mitogen stimulation between the groups was not statistically significant. These results suggest that beta-chemokines do not play an important role in HIV-1 progression in children undergoing HAART.  相似文献   
992.
Agave intermixta Trel. and Cissus sicyoides L. are two tropical plants originating from the Dominican Republic. Aqueous extracts from these species are used in traditional medicine. In contrast, biological activity and toxicity of these plants are not yet evaluated systematically. The aim of the present work is to investigate a potential anti-inflammatory activity, and to elucidate the toxicity of the extracts. No lethal effects were produced after oral administration of the extracts. The values of the medium lethal doses after intraperitoneal administration were quite high for both species, although A. intermixta seems to be rather more toxic than C. sicyoides. The anti-inflammatory effects have been investigated in two experimental in vivo models. The carrageenan-induced rat paw oedema was chosen as a model for general inflammation, and the mice ear oedema test using tetradecanoylphorbol acetate as inflammatory agent as a model of topical inflammation. Dry extracts from decoctions of A. intermixta leaves and C. sicyoides stems were administered in doses of 300 and 500 mg/kg (p.o.) in the general model, and in doses of 3 and 5 mg/mouse ear for both plants in the topical model. In the general anti-inflammation assay, the oral administration of both extracts produced a significant anti-inflammatory effect, most pronounced for A. intermixta than for C. sicyoides. In the topical model, the administration of both extracts produced similar inhibitions of the oedema, with a reduction of approximately 50% in comparison with the control group. In homogenated tissue samples from the inflamed areas, a distinct decrease in the level of myeloperoxidase enzyme was noted.  相似文献   
993.
The synthesis of new N-(4-pyridyl)-1-aminopyrazoles is described. Their binding properties were tested for muscarinic and other neurotransmitter receptors, together with their acetylcholinesterase inhibitory activity. The series derived from 3,5-dimethyl-1H-pyrazole showed moderate activities in both muscarinic and adrenergic receptor binding tests.  相似文献   
994.
The penetration and intracellular activity of ofloxacin and its isomers (levofloxacin and D-ofloxacin) into human polymorphonuclear leucocytes (PMN), human peritoneal macrophages (PMphi) and tissue cultured epithelial cells (McCoy) were evaluated. The cellular to extracellular concentration (C/E) values of the three fluoroquinolones were higher than 3.6 and 2.6 in PMN and PMphi, respectively. The C/E ratios in McCoy cells were lower than those in PMN, but still higher than 2.0. The uptake of ofloxacin and its isomers was rapid, non-saturable and reversible. All quinolones (extracellular concentrations: 2, 5 and 10 mg/l) produced a significant reduction of viable intraphagocytic Staphylococcus aureus in phagocytic cells. We concluded that ofloxacin and its isomers reach high intracellular concentrations in phagocytic and non phagocytic cells while remaining active in the former.  相似文献   
995.
The present study assesses how certain stress and coping variables relate to drug use. A total of 124 subjects (85 men, 39 women) took part. They were divided into two groups: consumers and low or nonconsumers. Results indicate that consumers show significantly lower scores in self-control than low or nonconsumers. This research is of interest because it analyzes the relationship among assertiveness, self-control, self-efficacy, and drug use. We consider it worthwhile to take these variables into account when planning prevention programs.  相似文献   
996.
At present, the frequency of intracranial complications of middle ear infections has decreased sharply as a result of the use of more effective antibiotics. We report two cases of lateral sinus thrombosis, in a 2-year-old male and a 14-year-old male respectively, after middle ear infection that progressed to mastoiditis with osteitis. The severity of these complications underlines the importance of clinical awareness and early diagnosis by angiographic magnetic resonance imaging so that suitable treatment can be begun.  相似文献   
997.
Granular cell tumors (GCT) are rare and usually benign tumors whose histogenesis is debated. The skin, subcutaneous tissues, and mucosae of the head and neck are areas of predilection for GCT. Laryngeal involvement is uncommon, but may create diagnostic and therapeutic problems when it occurs. Laryngeal GCT are decidedly uncommon in children, only 17 cases having been reported in the literature. A case of GCT of the larynx in an 11-year-old girl is reported. The presenting symptom was hoarseness. The macroscopic tumor and hoarseness disappeared after chemotherapy (EVAIA) for Ewing sarcoma of the knee.  相似文献   
998.
Lingual abscesses have become extremely rare since the discovery of antibiotics, with only about 200 cases reported in the last 160 years. Diagnosis on the basis of clinical symptoms alone is quite difficult. Imaging studies are essential for the diagnosis of lingual abscesses and for their differentiation from related pathologies with similar clinical symptoms. We report a case of lingual abscess with otherwise unremarkable clinical findings that was diagnosed by CT scan. The etiology, pathophysiology, bacteriology, diagnosis, and treatment of these uncommon infections is discussed.  相似文献   
999.
Involvement of the cervical lymph nodes is one of the commonest forms of extrapulmonary tuberculosis. Given this, we carried out a retrospective study of those cases diagnosed in our health region from 1995-1997, looking at the diagnostic criteria and treatment regimes and comparing our findings with those of other authors.  相似文献   
1000.
Lack of a specific and definitive treatment for recurrent aphthous stomatitis allowed to develop several assays with different drugs trying to lighten symptoms and avoid new crisis. The pathophysiological unknown about the illness forces to empiric therapies often disappointing. Immunomodulation by the haemorreoactive agent pentoxifylline inhibiting the *-TNF production seems to produce a neutrophilic and lymphocytic hypoactivity state, which promotes healing of aphthous in AIDS. Nevertheless, its use on healthy subjects got to prevent new episodes just in the 36% from our eleven cases, which is an improvement if compared to other local and systemic alternatives. Congenital or acquired immune factors still undetected determine the sensibility of subject to treatment and different healing rates reported by authors depending on pathologies.  相似文献   
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