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31.
Brian K Owler Shahan Momjian Zofia Czosnyka Marek Czosnyka Alonso Péna Neil G Harris Piotr Smielewski Tim Fryer Tim Donovan Jonathon Coles Adrian Carpenter John D Pickard 《Journal of cerebral blood flow and metabolism》2004,24(1):17-23
Regional cerebral blood flow (CBF) was studied with O(15)-water positron emission tomography and anatomic region-of-interest analysis on co-registered magnetic resonance in patients with idiopathic (n = 12) and secondary (n = 5) normal pressure hydrocephalus (NPH). Mean CBF was compared with values obtained from healthy volunteers (n = 12) and with clinical parameters. Mean CBF was significantly decreased in the cerebrum and cerebellum of patients with NPH. The regional analysis demonstrated that CBF was reduced in the basal ganglia and the thalamus but not in white matter regions. The results suggest that the role of the basal ganglia and thalamus in NPH may be more prominent than currently appreciated. The implications for theories regarding the pathogenesis of NPH are discussed. 相似文献
32.
GM-CSF induces expression of soluble VEGF receptor-1 from human monocytes and inhibits angiogenesis in mice 总被引:5,自引:0,他引:5
GM-CSF promotes homeostasis of myeloid cells. We report that GM-CSF upregulates mRNA and protein production of the soluble form of membrane bound VEGF receptor-1 (sVEGFR-1) in human monocytes. This sVEGFR-1 was biologically active, as cell-free supernatants from GM-CSF-stimulated monocytes blocked detection of endogenously expressed VEGF and inhibited endothelial cell migration and tube formation, even in the presence of exogenous rhVEGF. VEGF activity was recovered by neutralizing sVEGFR-1. To determine whether these events were important in vivo, Matrigel plugs were incubated with rhVEGF, rhGM-CSF, or rhGM-CSF/rhVEGF and injected into mice. Plugs containing GM-CSF or GM-CSF/VEGF had less endothelial cell invasion than plugs containing rhVEGF and were similar to plugs incubated with PBS alone. Neutralizing antibodies specific for sVEGFR-1 injected in these plugs reversed the effects of GM-CSF or GM-CSF/VEGF, while an isogenic antibody did not. Thus, GM-CSF and monocytes play a vital role in angiogenesis through the regulation of VEGF and sVEGFR-1. 相似文献
33.
The major histocompatibility complex (CyLA) of the cynomolgus monkey. I. Serologic definition of 21 specificities 总被引:1,自引:0,他引:1
Thirty-seven lymphocytotoxic antisera, 27 of which were raised by immunization with skin grafts and blood from partially matched donors, were tested against cells obtained from 218 unrelated animals and 205 offspring from a colony of cynomolgus monkey (Macaca fascicularis). Evidence was obtained for the presence of at least 21 specificities defined by cluster analysis and segregation within families. Allelic relationships between 16 specificities was suggested by segregation patterns, the absence of triplets and statistical analysis of association in the unrelated population sample. The data support a two-locus model, with tentative assignment of seven specificities to the A locus and six to the B locus. That these lymphocyte alloantigens constitute the major histocompatibility complex (MHC) of the cynomolgus monkey is suggested by analogy with other known MHCs and by the increased survival times of skin grafts between paternally matched half sibs compared to haplodistinct full sibs. 相似文献
34.
Factors associated with the provision of anti-smoking advice in general practice consultations. 下载免费PDF全文
Alison Wynn Tim Coleman Stephen Barrett Andrew Wilson 《The British journal of general practice》2002,52(485):997-999
Guidelines urge general practitioners (GPs) to discuss smoking with patients as frequently as possible. Using data collected before and after consultations, this study confirms that GPs are more likely to discuss smoking in the context of smoking-related problems. Encouraging GPs to make greater use of problem-orientated opportunities to discuss smoking may have more effect on rates of advice giving than urging them to advise all smokers. 相似文献
35.
Edward D. Levin Todd C. Brady Elizabeth Crapo Hochrein Tim D. Oury Lena M. Jonsson Stefan L. Marklund James D. Crapo 《Behavior genetics》1998,28(5):381-390
Extracellular superoxide dismutase (EC-SOD) controls the availability of extracellular superoxide (O
2
-
), which is important for a variety of physiological pathways, including the primary means of inactivating nitric oxide (NO). The role of EC-SOD in neurobehavioral function has been until now unexplored. In the current studies, the phenotypic expression of genotypic alterations of EC-SOD production in mice were characterized for spatial learning and memory. Dramatic impairments in spatial learning in the win-shift 8-arm radial maze were seen in both EC-SOD knockout mice and EC-SOD overexpressing mice. The EC-SOD overexpressing mice were further characterized as having significant deficits in a repeated acquisition task in the radial-arm maze, which permitted the dissociation of long and short-term learning. Long-term learning was significantly impaired by EC-SOD overexpression, whereas short-term learning was not significantly affected by EC-SOD overexpression. NO systems have been shown to be importantly involved in learning and memory. This may be important in the current studies because EC-SOD has primary control over the inactivation of NO. We found that EC-SOD overexpressing mice were resistant to the cognitive effects of L-NAME (NG-nitro-L-arginine methyl ester hydrochloride), an NO synthase inhibitor. Decreased NO catabolism in these mice may have served to counter the effects of NOS inhibition by L-NAME. The current finding that EC-SOD levels that were either higher or lower than controls impaired learning demonstrates that the proper control of brain extracellular (O
2
-
) may be more vital than merely reduction of brain extracelluar (O
2
-
) in maintaining adequate learning function. 相似文献
36.
A mutation in the gene TNFRSF11B encoding osteoprotegerin causes an idiopathic hyperphosphatasia phenotype 总被引:5,自引:0,他引:5
37.
This paper describes the outcomes of episodes of care for adults in public sector mental health services across Australia, with a view to informing the debate on service quality. Health of the Nation Outcome Scales (HoNOS) change scores and effect sizes were calculated for 14,659 acute inpatient episodes and 23,692 community episodes. The results showed that people in contact with public sector mental health services generally do get better, although the magnitude of improvement depends on the setting and episode type. This confirmatory finding is particularly positive, given current community concerns about the quality and effectiveness of mental health services. 相似文献
38.
Ian M Mackay Tim Gardam Katherine E Arden Suzi McHardy David M Whiley Erin Crisante Theo P Sloots 《Journal of clinical virology》2003,28(3):291-302
BACKGROUND: Herpesviruses are a significant cause of human morbidity. Traditional approaches to the identification of these viruses require infectious or at least antigenic virus. Multiplex PCR (mPCR) is capable of simultaneously amplifying a range of targets from a single preparation of nucleic acids and when combined with a suitable detection assay, it is capable of discriminating each of the amplicons. OBJECTIVES: Several methods have been described in the literature, however, they lack one or more significant design features required to suitably control a routinely applied nucleic acid amplification assay. We aimed to design a multiplex herpesvirus PCR that could co-amplify eight human herpesvirus targets plus an internal control (IC) molecule in a single tube. STUDY DESIGN: Primers were designed to target the DNA polymerase genes of each of the human herpesviruses. Synthetic controls were developed to act as templates for the evaluation of assay sensitivity and specificity and for development of an in-house competitive quantitative PCR. Amplicon was discriminated using a simplified enzyme linked amplicon hybridisation assay (ELAHA). RESULTS AND CONCLUSIONS: For routine diagnostic use we reduced the number of herpesviral targets from 8 to 6 in order to maintain adequate clinical sensitivity. The ELAHA proved more sensitive than agarose gel electrophoresis. Additionally, 36 cytomegalovirus positive patients were examined with an in-house quantitative PCR-ELAHA which was developed to confirm that that the mPCR's co-detection limit of 10(2) copy of synthetic template per millilitre was relevant for use in detecting virus from clinical samples. The mPCR-ELAHA was then applied to the screening of 174 patient specimens resulting in a specificity of 98% and a sensitivity of 93%. This preliminary study demonstrated that the mPCR-ELAHA was a complete approach to the detection of herpesviruses from a range of clinical samples and disease states. 相似文献
39.
40.
Autocrine motility factor (AMF) is one of the motility cytokines regulating tumor cell migration, therefore identification
of the signaling pathway coupled with it has critical importance. Previous studies revealed several elements of this pathway
predominated by lipoxygenase-PKC activations but the role for tyrosine kinases remained questionable. Motility cytokines frequently
have mitogenic effect as well, producing activation of overlapping signaling pathways therefore we have used B16a melanoma
cells as models where AMF has exclusive motility effect. Our studies revealed that in B16a cells AMF initiated rapid (1–5
min) activation of the protein tyrosine kinase (PTK) cascade inducing phosphorylation of 179, 125, 95 and 40/37 kD proteins
which was mediated by upstream cyclo- and lipoxygenases. The phosphorylated proteins were localized to the cortical actin-stress
fiber attachment zones in situ by confocal microscopy. On the other hand, AMF receptor activation induced significant decrease
in overall serine-phosphorylation level of cellular proteins accompanied by serine phosphorylation of 200, 90, 78 and 65 kd
proteins. The decrease in serine phosphorylation was independent of PTKs, PKC as well as cyclo- and lipoxygenases. However,
AMF induced robust translocation of PKCα to the stress fibers and cortical actin suggesting a critical role for this kinase
in the generation of the motility signal. Based on the significant decrease in serine phosphorylation after AMF stimulus in
B16a cells we postulated the involvement of putative serine/threonine phosphatase(s) upstream lipoxygenase and activation
of the protein tyrosine kinase cascade downstream cyclo- and lipoxygenase(s) in the previously identified autocrine motility
signal.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献