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81.
Mice deficient for the IL-1RAcP gene (IL-1RAcP KO) were used to explore the role of IL-1RAcP in physiological functions of brain IL-1beta. Animals were injected i.c.v. with two different doses of recombinant human (rh) IL-1beta: a small one (750 pg) known to induce sickness behavior, and a larger one (50 ng), chosen to counteract the possible loss of affinity of IL-1beta on its receptor. Neuroendocrine and immune parameters were measured 2 h after IL-1 injection. The increase of plasma corticosterone induced by rhIL-1beta in wild-type (WT) mice was not observed in IL-1RAcP KO mice. Likewise, the depression of splenocyte proliferation occurred in WT but not in KO mice. Finally, in opposition to WT mice, plasma levels and brain cortical content of IL-6 in IL-1RAcP KO mice remained unchanged as compared to saline-injected controls. The results clearly demonstrate that IL-1RAcP is necessary for the induction of the main neuroendocrine and immune effects of central IL-1beta.  相似文献   
82.
OBJECTIVE: We prospectively studied children with and without maternally transmitted HIV-1 infection born to mothers infected with HIV-1 to determine the incidence of chronic radiographic lung changes (CRC) and to correlate these changes with clinical assessments. SUBJECTS AND METHODS: Between 1990 and 1997, we scored 3050 chest radiographs using a standardized form. Group I children (n = 201) were HIV-1-infected at enrollment. Group II children (n = 512) were enrolled prenatally or before 28 days postpartum and subsequently subdivided into group IIa (n = 86), children identified as HIV-1-infected; and group IIb (n = 426), those who were HIV-1-uninfected. CRC were defined as parenchymal consolidations or nodular disease lasting 3 months or more or increased bronchovascular markings or reticular densities lasting 6 months or more. Morbidity was assessed by CD4 counts, viral load, the presence of low oxygen saturation, wheezing, tachypnea, crackles, and clubbing. RESULTS: The cumulative incidence of chronic radiographic lung changes in HIV-1-infected children was 32.8% by 4 years old, with increased bronchovascular markings or reticular densities being most common. Chronic changes were associated with lower CD4 cell counts and higher viral loads. Resolution of these chronic changes was associated with decreasing CD4 cell counts but not with lower rates of clinical findings, viral load, or difference in survival. CONCLUSION: With increased survival, CRC are becoming more common. The resolution of these changes may indicate immunologic deterioration rather than clinical improvement.  相似文献   
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The aetiology of 197 girls and 16 boys presenting with sexual precocity was reviewed. Ninety one girls and four boys had central precocious puberty (M:F 23:1); a cause was identified in all the boys but in only six girls. All boys with precocious puberty need detailed investigation; in girls investigation should be based on clinical findings, particularly the consonance of puberty.  相似文献   
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The product of the enzyme-catalyzed conjugation of glutathioneand 4-nitroquinoline 1-oxide was isolated and its structuredetermined by MS and NMR. The results indicate that the cysteinesulfur of glutathione replaces the nitro group of 4-nitroquinoline1-oxide in the reaction with the formation of 4-(glutathion-S-yI)-quinoline1-oxide. No evidence was found for the binding of glutathioneto any other position of 4-nitroquinoline 1-oxide or throughany group other than the cysteine sulfur.  相似文献   
87.
1. Following the administration of daily oral doses (1 mg/kg) of 2,5,4'-trichloro-[14C]biphenyl to rats for 14 days, the compound was rapidly excreted, only small amounts (3--4%) being stored in the organs. 2. The majority of the biphenyl was metabolized (greater than 85%) and the major metabolites excreted were identified as hydroxy-, dechloro- and conjugated derivatives.  相似文献   
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The authors describe various patterns of F-18 fluorodeoxyglucose (FDG) accumulation in the diaphragm and crura. They present 6 patients in whom incidental diaphragmatic and crural uptake of FDG was observed during positron emission tomography (PET). Hyperventilation is thought to be the potential underlying mechanism of this condition.  相似文献   
90.
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