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81.
Summary Histochemical techniques for acetylcholinesterase and catecholamine show that ureterovesical ganglia of both cat and dog contain dense intraganglionic cholinergic and adrenergic plexuses. Ramifications of both plexuses surround most cholinergic and adrenergic ganglion cell bodies as pericellular synaptic plexuses. Similar pericellular plexuses exist around extraganglionic cholinergic and adrenergic ganglion cells. Both adrenergic and cholinergic synaptic fibers persist in denervated pregnaglionic nerve-free specimens, indicating that cholinergic synaptic fibers are postganglionic parasympathetic in nature. The presence of adrenergic (postganglionic sympathetic) and postganglionic parasympathetic synapses around cell bodies in ureterovesical ganglia provides a morphologic basis for the sympathoinhibitory and muscarinic parasympatho-excitatory phenomena described in these ganglia. 相似文献
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Plant pathogenic bacteria possess a large number of genes that allow them to grow and cause disease on plants. In planta gene expression analysis is important to understand the impact of these genes on bacterial virulence. A new mRNA-based approach using multiplexed Northern hybridization was developed. High-quality bacterial and plant total RNA was successfully isolated from leaf tissue infiltrated with Pseudomonas syringae . The procedure employs a new extraction buffer formulation containing glycine, sodium dodecylsulphate, cetyltrimethylammonium bromide, high-molecular-weight polyethylene glycol and β-mercaptoethanol. Cell lysis and classical acid–phenol extraction steps followed by LiCl precipitation yielded large amounts of total RNA of high purity and integrity. Multiplexing of DIG and chemically fluorescently labelled RNA probes was developed and expression data were normalized using the 23S rRNA gene as reference. The method was validated by studying in planta expression of the P. syringae genes mucD , cmaA , cfl , corR , corS and corP comprising a selection of highly expressed biosynthetic and low-expressed regulatory genes. The method was assessed regarding its sensitivity and might by useful for studying a variety of plant–microbe interactions. 相似文献
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Background
Authority and year information have been attached to taxonomic names since Linnaean times. The systematic structure of taxonomic nomenclature facilitates the ability to develop tools that can be used to explore historical trends that may be associated with taxonomy. 相似文献85.
86.
Ballard C Lana MM Theodoulou M Douglas S McShane R Jacoby R Kossakowski K Yu LM Juszczak E;Investigators DART AD 《PLoS medicine》2008,5(4):e76
Background
There have been increasing concerns regarding the safety and efficacy of neuroleptics in people with dementia, but there are very few long-term trials to inform clinical practice. The aim of this study was to determine the impact of long-term treatment with neuroleptic agents upon global cognitive decline and neuropsychiatric symptoms in patients with Alzheimer disease.Methods and Findings
Design: Randomised, blinded, placebo-controlled parallel two-group treatment discontinuation trial.Setting: Oxfordshire, Newcastle and Gateshead, London and Edinburgh, United Kingdom.Participants: Patients currently prescribed the neuroleptics thioridazine, chlorpromazine, haloperidol trifluoperazine or risperidone for behavioural or psychiatric disturbance in dementia for at least 3 mo.Interventions: Continue neuroleptic treatment for 12 mo or switch to an identical placebo.Outcome measures: Primary outcome was total Severe Impairment Battery (SIB) score. Neuropsychiatric symptoms were evaluated with the Neuropsychiatric Inventory (NPI).Results: 165 patients were randomised (83 to continue treatment and 82 to placebo, i.e., discontinue treatment), of whom 128 (78%) commenced treatment (64 continue/64 placebo). Of those, 26 were lost to follow-up (13 per arm), resulting in 51 patients per arm analysed for the primary outcome. There was no significant difference between the continue treatment and placebo groups in the estimated mean change in SIB scores between baseline and 6 mo; estimated mean difference in deterioration (favouring placebo) −0.4 (95% confidence interval [CI] −6.4 to 5.5), adjusted for baseline value (p = 0.9). For neuropsychiatric symptoms, there was no significant difference between the continue treatment and placebo groups (n = 56 and 53, respectively) in the estimated mean change in NPI scores between baseline and 6 mo; estimated mean difference in deterioration (favouring continue treatment) −2.4 (95% CI −8.2 to 3.5), adjusted for baseline value (p = 0.4). Both results became more pronounced at 12 mo. There was some evidence to suggest that those patients with initial NPI ≥ 15 benefited on neuropsychiatric symptoms from continuing treatment.Conclusions
For most patients with AD, withdrawal of neuroleptics had no overall detrimental effect on functional and cognitive status. Neuroleptics may have some value in the maintenance treatment of more severe neuropsychiatric symptoms, but this benefit must be weighed against the side effects of therapy.Trial registration: Cochrane Central Registry of Controlled Trials/National Research Register (#ISRCTN33368770). 相似文献87.
Pandemic human viruses cause decline of endangered great apes 总被引:3,自引:0,他引:3
Köndgen S Kühl H N'Goran PK Walsh PD Schenk S Ernst N Biek R Formenty P Mätz-Rensing K Schweiger B Junglen S Ellerbrok H Nitsche A Briese T Lipkin WI Pauli G Boesch C Leendertz FH 《Current biology : CB》2008,18(4):260-264
Commercial hunting and habitat loss are major drivers of the rapid decline of great apes [1]. Ecotourism and research have been widely promoted as a means of providing alternative value for apes and their habitats [2]. However, close contact between humans and habituated apes during ape tourism and research has raised concerns that disease transmission risks might outweigh benefits [3-7]. To date only bacterial and parasitic infections of typically low virulence have been shown to move from humans to wild apes [8, 9]. Here, we present the first direct evidence of virus transmission from humans to wild apes. Tissue samples from habituated chimpanzees that died during three respiratory-disease outbreaks at our research site, C?te d'Ivoire, contained two common human paramyxoviruses. Viral strains sampled from chimpanzees were closely related to strains circulating in contemporaneous, worldwide human epidemics. Twenty-four years of mortality data from observed chimpanzees reveal that such respiratory outbreaks could have a long history. In contrast, survey data show that research presence has had a strong positive effect in suppressing poaching around the research site. These observations illustrate the challenge of maximizing the benefit of research and tourism to great apes while minimizing the negative side effects. 相似文献
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Observed genotypic difference in P utilization efficiency in soil grown potatoes led to the present study to investigate possible mechanisms of P utilization efficiency in potato genotypes grown in nutrient solution under three P regimes (low, medium and high). For all genotypes relative growth rate (RGR), leaf P content, net assimilation rate (NAR) and leaf area ratio (LAR) increased while P utilization efficiency and leaf starch content decreased at the two higher P regimes compared to the low P regime. The P-efficient genotypes CGN 17903 and CIP 384321.3 had higher RGR compared to the P-inefficient genotypes CGN 22367 and CGN 18233, which resulted from enhanced NAR rather than from LAR. Net photosynthetic rate was similar for all genotypes. However, for P-inefficient genotype CGN 22367, the lower NAR could be explained by increased leaf dark respiration. For P-inefficient genotype CGN 18233 we speculate that increased carbon cost of root respiration or exudation or both, caused low NAR, since leaf dark respiration of this genotype was similar to that of P-efficient genotypes. 相似文献