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131.
Three groups of four calves were used to determine whether Ehrlichia phagocytophila could be transmitted orally to calves via infected milk. Groups 1 and 2 consisted of four-week-old calves and group 3 of newborn calves. The calves in group 1 were fed for several days with milk from cows infected experimentally with E phagocytophila. The calves in groups 2 and 3 were fed 200 ml of whole blood containing E phagocytophila organisms; for group 2 the blood was added to milk before being fed, and for group 3 the blood was added to colostrum before being fed within three hours after birth. Blood samples for haematological, serological and cytological examination, and for polymerase chain reaction (PCR) were collected from all the calves, starting on the first or only day of administration and then every four days for four weeks. The calves of groups 1 and 2 showed no clinical, haematological or serological changes, and there was no direct or indirect evidence of the agent. In contrast, all the calves in group 3 had mild pyrexia and seroconverted on day 8, and in one of them E phagocytophila organisms were visible in leucocytes, and the PCR on the buffy coat was positive on day 8.  相似文献   
132.
Objective: Icon arrays have been suggested as a potentially promising format for communicating risks to patients—especially those with low numeracy skills—but experimental studies are lacking. This study investigates whether icon arrays increase accuracy of understanding medical risks, and whether they affect perceived seriousness of risks and helpfulness of treatments. Design: Two experiments were conducted on samples of older adults (n = 59, 62 to 77 years of age) and university students (n = 112, 26 to 35 years of age). Main Outcome Measures: Accuracy of understanding risk reduction; perceived seriousness of risks; perceived helpfulness of treatments. Results: Icon arrays increased accuracy of both low- and high-numeracy people, even when transparent numerical representations were used. Risks presented via icon arrays were perceived as less serious than those presented numerically. With larger icon arrays (1,000 instead of 100 icons) risks were perceived more serious, and risk reduction larger. Conclusions: Icon arrays are a promising way of communicating medical risks to a wide range of patient groups, including older adults with lower numeracy skills. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
133.
Highly enriched methanotrophic communities (> 25 serial transfers) were obtained from acidic ombrotrophic peat bogs from four boreal forest sites. The enrichment strategy involved using media conditions that were associated with the highest rates of methane uptake by the original peat samples, namely, the use of diluted mineral medium of low buffering capacity, moderate incubation temperature (20 degrees C), and pH values of 3 to 6. Enriched communities contained a mixture of rod-shaped bacteria arranged in aggregates with a minor contribution of Hyphomicrobium-like cells. The growth stoichiometry of isolates was characteristic of methanotrophic bacteria (CH4/O2/CO2 = 1:1.1:0.59), with an average apparent yield of 0.41 +/- 0.03 g of biomass C/g of CH4-C. DNA from each enrichment yielded a PCR product of the expected size with primers for both mmoX and mmoY genes of soluble methane monooxygenase. Two types of sequences were obtained for PCR-amplified fragments of mmoX. One of them exhibited high identity to the mmoX protein of the Methylocystis-Methylosinus group, whereas the other showed an equal level of divergence from both the Methylosinus-Methylocystis group and Methylococcus capsulatus (Bath) and formed a distinct branch. The pH optimum for growth and for CH4 uptake was 4.5 to 5.5, which is very similar to that for the optimum CH4 uptake observed in the original peat samples. These methanotrophs are moderate acidophiles rather than acidotolerant organisms, since their growth rate and methane uptake were much lower at neutral pH. The growth of the methanotrophic community was enhanced by using media with a very low salt content (20 to 200 mg/liter), more typical of their natural environment. All four enriched communities grew on N-free medium.  相似文献   
134.
The intraperitoneal injection of Balb/c mice with synthetic analogues of adjuvants S-[2,3-bis(palmitoyloxy)-(2-RS)-propyl]-N-palmitoyl-R-cysteine (Pam3Cys) or muramyltripeptide phosphatidylethanolamine (MTP-PE) inhibited the tumourigenic growth of subcutaneously injected VLM cells, a syngeneic simian virus 40 (SV40)-transformed cell line. Furthermore, the Pam3Cys conjugate of K698-T708 (KT), which represents the C-terminal undecapeptide of the SV40 large tumour (T) antigen, was tumour-protective. Also syngeneic spleen cells, preincubated in vitro with this Pam3Cys-KT derivative, which anchores spontaneously at the cell membrane, were, through SV40 tumour mimicry, tumour-protective. The protection was impaired by treatment of the mice with either anti-CD4, anti-CD8 IgG, anti asialo GM1 antiserum or dextrane sulfate, which deplete the CD4+, CD8+ and NK cells or the macrophages, respectively. In summary, SV40 tumour transplantation resistance can be experimentally elicited by a tumour-epitope-specific vaccine. In the absence of an immunogenic epitope protection was obtained by administration of biological response modifiers. Protection is effected by SV40-T-antigen-specific cytotoxic lymphocytes in cooperation with NK cells and macrophages.  相似文献   
135.
The purpose of this prospective study was to evaluate the effect of prophylactic antibiotic treatment on postoperative antibiotic spinal wound infection after spinal surgery with instrumentation. Subjects consisted of 110 successive patients that underwent instrumented fusion with Cotrel-Dubousset (CD) or Miami Moss instrumentation. In 56 cases, the indication for surgery was painful spondylolisthesis. The remaining 54 patients were treated for idiopathic scoliosis. In total, 172 spinal procedures were performed and included in the study. Preoperative infection prophylaxis consisting of 2 g cefamandole was administered to all patients. Patients received three doses of 2 g/day cefamandole after surgery for 3 days. Follow-up ranged from 1 to 4 years. The study revealed an early infection in one (0.6%) of the 172 procedures in a patient with spondylolisthesis. A late infection occurred in one (0.6%) patient with the diagnosis of idiopathic scoliosis. In both cases, cultures were positive for Staphylococcus aureus.  相似文献   
136.
An attempt was made to clarify whether the site of postchiasmal lesions affects subjective perception of homonymous visual field defects during stimulation with flickering random dot patterns (white noise-field). Out of 56 patients with homonymous hemianopia, 38 (68%) perceived scotomata in this situation, but 18 (32%) discerned none at all. Neuroradiologic superposition of cerebral lesions detected by computed tomography (CT) or magnetic resonance imaging (MRI) showed that nearly all patients who perceived their scotomata had lesions involving the primary visual cortex or the perigeniculate region, whereas those who received no scotoma had lesions centered within the optic radiation. Functional MRI of six normal subjects during stimulation with flickering random dot patterns indicated predominant activation of the primary visual cortex. Since noise-field defects were most frequently perceived by patients whose lesion involved the primary visual cortex, it appears that the sensitivity of noise-field campimetry depends on the site of damage in the visual pathway. The explanation for this may be that damage to long-range horizontal connections impairs filling-in processes.  相似文献   
137.
A region of dorsomedial frontal cortex (DMFC) has been implicated in planning and executing saccadic eye movements; hence it has been referred to as a supplementary eye field (SEF). Recently, activity related to executing smooth-pursuit eye movements has been recorded from the DMFC, and microstimulation here has been shown to evoke smooth eye movements. This report documents neuronal activity present in smooth-pursuit tasks where the predictability of target motion was manipulated. The activity of many neurons in the DMFC reached a peak when a predictable change in target motion occurred. Furthermore, the peak activity of some cells was systematically shifted by manipulating the duration of the target event, indicating that the network these neurons were in could learn the temporal characteristics of new target motion. Finally, the activity of most neurons tested was greater when target motion was predictable than when it was unpredictable. The results suggest that the DMFC participates in planning smooth-pursuit eye movements based on past stimulus history.  相似文献   
138.
At very high temperatures loaded metallic structures undergo creep deformations. The generated creep strains are connected with stress relaxations, stress redistributions and/or progressive deformations.In mainly load controlled situations the behaviour of the material can be described by a nonlinear viscous flow law (Norton power law).A stress-deformation analysis of complex structures can be carried out by finite element codes in which the mentioned constitutive equation is implemented. The code PERMAS-VISCOUS was used to analyse the stress state of a notched tension bar and the deformation behaviour of a tube under external pressure undergoing a creep collapse. The relation to experimental findings is also given.  相似文献   
139.
Parasitic beam tunnel oscillations have been discovered on some of the series production gyrotrons for W7-X and also on the coaxial pre-prototype gyrotron for ITER. Solutions to remedy these problems have resulted in a modified beam tunnel design, technologically close to the existing beam tunnel. The new design has successfully been tested on both the coaxial and also the f-step-tunable gyrotrons and has subsequently been implemented on one of the W7-X series-production-tubes presently undergoing factory acceptance tests in Karlsruhe.The ECRH test loads at KIT are operated under normal atmospheric conditions. Several loads have eventually failed in 1 MW long pulse experiments and KIT has therefore started to design its own loads. The first KIT-load is based on a fixed conical mirror and an aluminum cylinder coated with a lossy material for increased absorption. The new load has so far successfully been used during the acceptance tests of two 1-MW CW gyrotrons. Nevertheless a new load based on pure (uncoated) stainless steel absorbers is being developed as a backup solution for the ongoing high priority gyrotron testing.A superconducting magnet capable of rapid field changes between 4.15 and 5.67 T for frequency step-tunable gyrotrons has been procured, has demonstrated a (static) field of 7.2 T and its capability of rapid field-changes.  相似文献   
140.
This paper discusses the mechanisms of two basic effects of thyroid hormones on atrial responses to beta-adrenergic agonists, i.e. increased inotropic sensitivity and decreased maximal contractile responsiveness. The increased sensitivity of atria to beta-adrenergic agonists under thyroid hormones appears to be related to increases in beta-adrenoceptor density and Gs/Gi protein ratio, leading to activation of Gs-mediated pathway, but suppression of Gi-mediated pathway of adenylate cyclase regulation. Therefore, the i/c concentrations of cAMP and corresponding inotropic responses achieve their maximums at lower doses of beta-adrenergic agonist. Thyroid hormones also decrease the expression of phospholamban, but increase the expression of sarcoplasmic reticulum Ca2+-pump. As a result, the basal activity of sarcoplasmic reticulum Ca2+-pump increases, but its beta-adrenergic activation through phosphorylation of phospholamban decreases. It is suggested that these changes are causal for decreased maximal inotropic and lusitropic responses of atria to beta-adrenergic agonists.  相似文献   
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