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991.
992.
A genome screen to identify genes influencing the age at Parkinson disease (PD) onset was completed using 276 families without parkin mutations. Significant evidence of linkage to chromosome 2p near the PARK3 locus (logarithm of odds [lod] = 4.8) was observed. Evidence of linkage was also detected to chromosomes 1q (lod = 3.0) and 8q (lod = 2.6). These data suggest that the genes influencing age at PD onset likely differ from those that contribute to PD susceptibility.  相似文献   
993.
Maralinga, South Australia was an important site in the United Kingdom nuclear weapons test programme. Seven bombs were exploded and a series of 'safety' tests carried out; the latter in particular disseminated appreciable amounts of uranium and plutonium over a wide area. A programme to clean up the test site over several years was instituted, with in-situ vitrification as a principal measure. The final report on the programme has now been published. However, both the programme and the Report are seriously flawed; this article provides criticisms of both.  相似文献   
994.
Growing evidence suggests that nasal deposition and transport along the olfactory nerve represents a route by which inhaled manganese and certain other metals are delivered to the rodent brain. The toxicological significance of olfactory transport of manganese remains poorly defined. In rats, repeated intranasal instillation of manganese chloride results in injury to the olfactory epithelium and neurotoxicity as evidenced by increased glial fibrillary acidic protein (GFAP) concentrations in olfactory bulb astrocytes. The purpose of the present study was to further characterize the nasal toxicity of manganese sulfate (MnSO(4)) and manganese phosphate (as hureaulite) in young adult male rats following subchronic (90-day) exposure to air, MnSO(4) (0.01, 0.1, and 0.5 mg Mn/m(3)), or hureaulite (0.1 mg Mn/m(3)). Nasal pathology, brain GFAP levels, and brain manganese concentrations were assessed immediately following the end of the 90-day exposure and 45 days thereafter. Elevated end-of-exposure olfactory bulb, striatum, and cerebellum manganese concentrations were observed following MnSO(4) exposure to > or = 0.01, > or = 0.1, and 0.5 mg Mn/m(3), respectively. Exposure to MnSO(4) or hureaulite did not affect olfactory bulb, cerebellar, or striatal GFAP concentrations. Exposure to MnSO(4) (0.5 mg Mn/m(3)) was also associated with reversible inflammation within the nasal respiratory epithelium, while the olfactory epithelium was unaffected by manganese inhalation. These results confirm that high-dose manganese inhalation can result in nasal toxicity (irritation) and increased delivery of manganese to the brain; however, we could not confirm that manganese inhalation would result in altered brain GFAP concentrations.  相似文献   
995.
996.
997.

Background  

"Alternatively-activated" macrophages are found in Th2-mediated inflammatory settings such as nematode infection and allergic pulmonary inflammation. Due in part to a lack of markers, these cells have not been well characterized in vivo and their function remains unknown.  相似文献   
998.
999.
A new antifungal agent, CJ-19,784 (I), was isolated from the fermentation broth of a fungus, Acanthostigmella sp. CL12082. Based on spectroscopic analyses, structure of I was determined to be 3'-bromo-2',5-dihydroxy-3,7,8-trimethoxy-flavone. Compound I inhibits the growth of pathogenic fungi, Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus with IC50 values of 0.11, 20 and 0.54 microg/ml, respectively.  相似文献   
1000.
RATIONALE: It has been suggested that the nucleus accumbens (NAcc) may be involved in heroin reward, and the core and shell regions respond differently following administration of a number of drugs of abuse. OBJECTIVE: The possible role of the NAcc core and shell subregions in the acquisition of heroin self-administration behaviour was investigated. METHODS: Rats were given selective excitotoxic lesions of either the nucleus accumbens core or shell before the acquisition of responding for i.v. heroin (0.04 mg/infusion) under a continuous reinforcement schedule in daily 3 h sessions. After sham-lesioned rats reached a stable baseline, a between-sessions heroin dose-response function was established. RESULTS: Rats with lesions of the NAcc shell did not differ significantly from sham controls in either the acquisition of heroin self-administration or in their heroin dose-response function. The NAcc core lesion group showed reduced levels of responding during the acquisition of heroin self-administration and a reduction in responding during the heroin dose-response function, although this behaviour was sensitive to changes in the dose of heroin. CONCLUSIONS: The NAcc shell does not appear to be critical for heroin self-administration, whereas the NAcc core, although apparently not essential in mediating the rewarding effect of i.v. heroin, may mediate processes that are of special importance during the acquisition of instrumental behaviour.  相似文献   
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