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11.
Electrical stimulation of the cerebellar fastigial nucleus (FN) elevates regional cerebral blood flow (rCBF) independently of cerebral metabolism (rCGU) throughout brain. One hour of FN stimulation also reduces, by up to 50%, the volume of the focal ischemic infarction produced by occlusion of the middle cerebral artery in rat. Protected areas correspond to the ischemic penumbra. Neuroprotection, while reversible, persists for weeks after 1h of stimulation. It cannot be attributed to increasing rCBF and/or reducing rCGU to improve matching of flow and metabolism. Conditional stimulation of FN initiates long-lived inhibition of expression of peri-infarction depolarizing waves, possibly by altering potassium-channel function and suppresses induction of inducible nitric oxide synthase (iNOS) and ICAM in cerebral microvessels. The brain contains intrinsic networks which may protect the brain from ischemic injury, possibly by producing widespread and longterm suppression of electrical excitability and/or and expression of proinflammatory molecules. 相似文献
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Hrafnkelsdottir K Valgeirsson J Bjarnadottir S Olafsdottir S Olafsdottir K Hedinsdottir ST Magnusdottir EV Gizurarson S 《International immunopharmacology》2007,7(9):1179-1184
DDT is used for pest control, causing health and environmental hazards in some parts of the world. The goal of this study was to assess whether immunization against a toxic compound could reduce the toxicant uptake of an organism, specifically to develop a DDT immunization that promotes the production of specific antibodies and assess whether it reduces DDT levels in the bodies of mice that are exposed to DDT by intake. BALB/c mice were immunized with DDT-keyhole limpet hemocyanine (DDT-KLH) conjugate (n=10) or unconjugated KLH (n=10), which was used as a control. After the immunization specific DDT antibodies in the mouse serum were determined by ELISA and then the mice were fed chow containing 40 mg/kg of DDT for 45 days. Finally, the concentration of DDT and its metabolites, DDE and DDD, in various tissues was measured by gas chromatography. Specific DDT antibody levels were significantly higher in the DDT immunized group than in the control group. DDT, DDE and DDD levels in adipose tissue, blood, brain and spleen were significantly reduced in the DDT immunized animals relative to control animals. However, DDT and DDD levels were higher in the liver compared to the control group. The findings indicate that the DDT immunization reduces the total uptake of DDT in animal tissues, which is reflected by the lower levels in adipose tissue, blood, brain and spleen. The elevated levels in liver suggest that DDT-antibody complexes in mouse serum are delivered to the liver. 相似文献
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The genes encoding effector molecules of mature T cells, IL-2, perforin and
IL-4, were found to be expressed in vivo in the most primitive subsets of
thymocytes of adult mice. These subsets have previously been identified by
their cell surface markers and by their expression of other T
lineage-associated genes. While IL-2, perforin and IL-4 are expressed in
distinct patterns, all three are expressed before the induction of RAG-1
and pre-TCR alpha mRNA expression, and are confined to subsets of cells
that apparently have not yet undergone commitment to the T lineage. Thus,
expression of T cell response genes appears to be one of the earliest
markers of lymphocyte differentiation. Activation events marked by CD69
induction occur in these early cell types, but the response gene expression
by these cells is separable from CD69 expression. IL-2 and perforin are
induced again much later in thymocyte development, during TCR-dependent
repertoire selection. At those stages, IL-2 protein and RNA levels per cell
are higher, but the fraction of cells expressing IL-2 appears to be much
lower than in the most immature stages. In addition, a striking feature of
the immature populations is the robust IL-2 expression by presumptive
immature NK cells. These findings are discussed in terms of the
developmental origins of lineage specificity in T cell response gene
regulation.
相似文献
15.
Support for involvement of the AHI1 locus in schizophrenia 总被引:1,自引:0,他引:1
Ingason A Sigmundsson T Steinberg S Sigurdsson E Haraldsson M Magnusdottir BB Frigge ML Kong A Gulcher J Thorsteinsdottir U Stefansson K Petursson H Stefansson H 《European journal of human genetics : EJHG》2007,15(9):988-991
Recently, markers in the Abelson Helper Integration Site 1 (AHI1) region were shown to be associated with schizophrenia in a family sample of Israeli-Arabs. Here, we report a study evaluating the relevance of the AHI1 region to schizophrenia in an Icelandic sample. Seven markers shown to confer risk in the previous report were typed in 608 patients diagnosed with broad schizophrenia and 1,504 controls. Odds ratios for the overtransmitted alleles in the Israeli-Arab families ranged from 1.15 to 1.29 in the Icelandic sample. After Bonferroni correction for the seven markers tested, two markers were significantly associated with schizophrenia. Thus, our results are in general agreement with the previous report, with the strongest association signal observed in a region upstream of the AHI1 gene. 相似文献
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核素检查由于无创伤性并可定量测肾功能,已被广泛用于肾移植监测。本文介绍如何应用~(99m)Tc-DTPA等几种放射性药物和显像技术诊断肾移植后各种外科并发症,急、慢性排斥反应,急性肾小管坏死和免疫抑制剂的毒性反应。 相似文献
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Juul A Magnusdottir S Scheike T Prytz S Skakkebaek NE 《International journal of andrology》2007,30(6):537-542
Voice break is a late, but characteristic event in male puberty. Assessment of age at voice break may be a relevant marker for epidemiological studies of male pubertal development. We investigated the timing of voice break and its association with explanatory variables [calendar year of admission in the boys choir and pre-pubertal body mass index (BMI)] by survival analysis techniques based on retrospective analyses of age at voice break in 463 Danish choir boys who were studied over a 10-year period. We found an overall median age at voice break of 14.0 [13.9-14.6] years, and a statistically significant downwards trend in age at voice break in the 10-year period (1994-2003) (log-rank test p = 0.0146). There was a statistically significant difference in age at voice break between boys in the different BMI quartiles in pre-puberty (p = 0.00822) with a tendency towards early voice break with increasing BMI standard deviation scores. Thus boys in the heaviest quartile at 8 years of age had an increased risk of early voice break (RR of 1.74 [1.14-2.65]) approximately 6 years later, compared with boys in the thinnest quartile. The earlier voice break seen during the 10-year observation period could however not exclusively be explained by a general increase in BMI in that period. Our findings indicate that puberty, as assessed by age at voice break in boys, may be starting earlier in Denmark as it has been observed in the USA, and suggest a relationship between pre-pubertal BMI and the timing of puberty. 相似文献