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91.
This study reports the metabolism of carbon-14labeled diisopropyl methylphosphonate (DIMP) in mink and rats, undertaken to better understand the dose-related mortality reported for mink in a previous study. In both male and female mink and rats, DIMP was rapidly absorbed after oral administration; it was metabolized by a saturable pathway to a single metabolite, isopropyl methylphosphonate (IMPA), which was rapidly excreted, primarily in the urine (90%). Fecal radioactivity, also identified as IMPA, was 1.7-3.1% of the administered dose. Female rats had a slower rate of conversion of DIMP to IMPA and less total excretion of IMPA than male rats. Metabolism of DIMP administered intravenously was not very different from that given orally in both species. These data indicate that mink absorb, metabolize, and excrete DIMP (as IMPA) in a manner very similar to mice, rats, and dogs.  相似文献   
92.
The pleiotropic cytokine interleukin-6 (IL-6) is thought to be involved in bone homeostasis. A number of bone resorbing agents have been shown to induce the release of IL-6 from bone. We wished to determine whether prostaglandin E2 (PGE2), which is a mediator of bone resorption, can elicit the production of IL-6. IL-6 was measured by the proliferative response of B9 hybridoma cells and could be completely neutralised by an anti-IL-6 antibody. Parietal bones from neonatal mice were maintained in culture in the presence of indomethacin (10(-6) M) with or without PGE2. The time course and dose-response to PGE2 of IL-6 production were determined. After 6 h in culture, 10(-8) M PGE2 produced significantly more IL-6 than the controls (P < 0.005). PGE2 (10(-6) M) stimulated the production of a mean of 12.8 ng/ml IL-6 over 6 h. Preincubating bones with indomethacin for 20 h prior to a 6 h culture with indomethacin led to a lowering of the production of IL-6 (mean 1.8 ng/ml) compared to bones cultured without the preincubation period (5.8 ng/ml). When the indomethacin preincubation period was used, a significant increase in IL-6 production was found with 10(-9) M PGE2 (P < 0.005), and 10(-6) M PGE2 caused the production of 39.9 ng/ml IL-6 over 6 h. Stripping endocranial and ectocranial membranes from bones demonstrated the membranes to be the major site of IL-6 production. However, intact bones were required for maximal stimulated IL-6 production.  相似文献   
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The authors report the occurrence of the first three clinical cases of Lyme disease in Mato Grosso do Sul State, including the first case of Lyme meningitis in Brazil. These were identified by clinical and laboratorial criteria. Anti-Borrelia burgdorferi antibody search was carried out through ELISA and Western Blotting techniques, the former providing identification of IgG class antibodies alone, in one only of those cases. Through Immunoblotting, the following features were found in serum: 5 IgG and 2 IgM bands for the first case; 7 IgG and 2 IgM bands for the second; and 5 IgG and 6 IgM bands for the third. In the latter, presence fo specific antibodies was searched in liquor, due to lymphomonocitary meningitis occurrence, and one IgM band was detected. After antibiotic therapy, all patients exhibited significant clinical and laboratorial improvement in their conditions along with symptom regression to the present moment.  相似文献   
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As revealed the velocities of urea decomposition in the citrate donor plasma with soluble urease and urease immobilized by addition to carboxymethyl ester of cellulose, 2-(3'-amino-4'-methoxyphenyl)-sulphonylethyl ester of cellulose, diethylaminoester of cellulose, stained with dichlortriazine stain, or graft copolymere of cellulose and polyglycidylmetacrylate were sufficiently close to one another. Preparations of immobilized urease can be repeatedly used for urea decomposition in the citrate donor blood. Periodical treatment of the mentioned preparations with cystein solution led to a lesser decrease of enzymatic activity of the immobilized urease after repeated use.  相似文献   
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蒋林涛 《世界电信》2003,16(4):39-41
目前人们面临网络建设方向的选择,QoS、安全性和可信任性、IP网的可运营性等关键技术成为未来网络发展重点。下一代IP网络将采用IP网的核心技术。结合电信网的设计理念,建设一个可管理、可运营的网络,为运营商提供一个可以达到电信网服务质量保证的IP网,建立可赢利的商业模型。第五代路由器由于采用有智能的网络处理器(NP),可以灵活加进对用户的管理等多种功能,完全适应下一代IP网的发展要求。  相似文献   
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Follow-up (5.5 years) of monkeys with a history of acute enterovirus uveitis (AEU) after intraocular infection with ophthalmotropic ECHO 11 and ECHO 19 strains showed progressive changes in the infected eye; destruction of the iris, formation of films in the anterior chamber of the eye, deformation of the pupil, and signs of cataract and glaucoma. A short (1-30 days) stage of active reproduction of infective virus (up to 10(10) TCD50/g tissue in the first days postinfection) was followed by the second very long stage of limited specific multiplication of virus in ocular tissues. The virus was not detected during the second stage, but its components (virusspecific antigen and crystalloid accumulations of virions) were found in ophthalmic and conjunctival tissues; moreover, high levels of neutralizing antibodies were detected in the blood. The results indicate AEU transformed into a stubborn persistent infection of the eye in monkeys. The findings of this follow-up and published reports about many-year follow-up of children with AEU permit us to classify a post-uveitis disease as a special nosological form of a persistent enterovirus infection and denote it as enterovirus post-uveitis syndrome. The main signs of this syndrome are a history of AEU, progressive destructive changes in the anterior segment of the eye, presence of virus components in ocular tissues in remote periods after infection, and high antibody level in the blood.  相似文献   
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BACKGROUND: Knowledge about the natural course of HPV infection is still limited. In this study we investigated the presence of HPV DNA after treatment and clinical clearance of infection. METHODS: Eighty-two women treated for genital HPV infection at the STD clinic in Uppsala were consecutively selected for the study. After treatment with podophyllotoxin, and in some cases laser vaporization, a cell sample was taken at the follow-up visit 6-12 months after clinical clearance of the lesions as evaluated by colposcopy. Samples were analysed with PCR to detect HPV DNA. As a reference group, women treated for cervical intraepithelial neoplasia (CIN) with laser surgery, either with cone biopsy or vaporization, were followed-up after 6 months for the presence of HPV DNA. RESULTS: Six to 12 months after clinical clearance of HPV infection, 39 (48%) of the women showed detectable HPV DNA in cell samples from the cervix. Of these, 26 (67%) were found to harbor high risk HPV, six (15%) low risk, and seven (18%) either had more than one HPV type or HPV that could not be classified. All but three of the women treated for CIN (90%) were negative for HPV DNA. CONCLUSION: After clinical clearance of genital HPV infection half of the women had detectable HPV DNA. This does not necessarily imply that transmission to a new partner may occur, but indicates this possibility. Only 10% of the CIN treated women harbored HPV DNA in the cell samples in spite of showing high risk HPV infection before treatment.  相似文献   
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