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401.
This paper describes the most significant diseases of farmed deer which have emerged over the last 30 or so years. It describes their characteristic signs, how control measures have evolved, their current status and gives an indication of future diagnostic and control measures. Overall, it shows that wild deer brought into a farming environment have developed some of the production limiting diseases which affect sheep and cattle, such as parasitism and trace element deficiencies. In addition, farmed deer are susceptible to potentially fatal diseases such as tuberculosis, malignant catarrhal fever and yersiniosis. A disease which has recently emerged and has the potential to be more serious than any of the above is Johne's disease. In North America, Chronic Wasting Disease occurs in captive and wild deer in only two states but has the potential to be a serious threat to wild and farmed deer elsewhere if it spreads. The zoonotic risks of diseases affecting deer are discussed, as well as stress, welfare and deer restraint. The productivity of farmed deer can be maximised by using a well-designed deer health programme integrated with good management and feeding.  相似文献   
402.
OBJECTIVE: The present study has examined the effect of vitamin E, the principal modulator of free radical activity, on electrophysiological parameters in patients with diabetic peripheral sensorimotor polyneuropathy, matched for duration of disease and metabolic control. RESEARCH DESIGN AND METHODS: A total of 21 subjects with type 2 diabetes were enrolled in this double-blind randomized placebo-controlled study (vitamin E, 11 patients; placebo, 10 patients). Patients were randomly assigned to receive either 900 mg vitamin E or placebo for 6 months. The average dietary vitamin E consumption of the subjects was similar during the study. The main outcome measure was the electrophysiological tests assessing nerve conduction. Fasting plasma glucose, HbA1, postprandial plasma glucose, and electrophysiological parameters in the basal state and after 6 months of treatment were studied. RESULTS: Glycemic indexes did not show any significant changes during the study, whereas nerve conduction improved significantly in 2 of the 12 studied electrophysiological parameters after 6 months in patients on vitamin E supplementation. The changes in the electrophysiological parameters were obvious in the median motor nerve fibers and tibial motor nerve fibers. Nerve conduction velocity in the median motor nerve fibers (P = 0.0019) and tibial motor nerve distal latency (P = 0.0284) improved significantly after 6 months of vitamin E supplementation. CONCLUSIONS: This study shows that defective nerve conduction in diabetic subjects with mild-to-moderate peripheral neuropathy may be improved by pharmacological doses of vitamin E supplementation. Further studies with a larger number of patients for longer periods of time are needed.  相似文献   
403.
We demonstrate that a surfactant-stabilized molten globule intermediate exists for recombinant human growth hormone (rhGH), is very hydrophobic, and tends to form aggregates. Characterization of this intermediate included equilibrium denaturation measured by electron paramagnetic resonance (EPR) and CD spectroscopy, assessment of aggregation during refolding, and fluorescence studies of its binding to the hydrophobic probe, 1-anilinonapthalene-8-sulfonate (1,8-ANS). We have found that at 4.5 M guanidinium hydrochloride (GuHCl), a molten globule intermediate of rhGH is stabilized and results in significant aggregation upon refolding. This intermediate is populated by the addition of the nonionic surfactant, Tween. This surfactant also reduces the extent of aggregation during refolding of rhGH from 4.5 M GuHCl. Overall, our studies reveal that rhGH forms a molten globule-like intermediate during folding and this intermediate self-associates. This self-association is reduced upon formation of a Tween-rhGH complex. Tween also binds to the native protein. Thus, nonionic surfactants such as Tween may act like molecular chaperones in facilitating protein folding while not altering the native conformation.  相似文献   
404.
OBJECTIVE: Goals were to determine how long acute-phase markers remain elevated after ischemic stroke and how marker levels relate to stroke risk factors, stroke mechanism, and subsequent vascular events. METHODS: Fibrinogen (FIB), C-reactive protein (CRP), leukocytes (WBC), neutrophils (PMN), interleukin-6, and interleukin-1 receptor antagonist were measured at stroke onset and at 6 weeks, 6 months, and 1 year after enrollment, or until a vascular event occurred in 136 acute ischemic stroke patients, 76 patients with comparable risk factors for stroke, and 48 age-balanced healthy subjects. RESULTS: Multivariate logistic analysis showed that prior stroke and FIB level predicted new events in stroke patients (p < 0.04 for both), whereas congestive heart failure (p < 0.02) and creatinine level (p < 0.006) were predictive in at-risk patients. After controlling for infection, FIB, CRP, and PMN levels at baseline were higher in at-risk but not in stroke patients with recurrent events (p < 0.05 for all). At 1 year, FIB levels remained elevated in event-free stroke survivors compared with levels in the risk and control groups (p < 0.001 for both). FIB also remained higher in stroke survivors who had atheroembolism (AE) compared with non-AE stroke survivors (381+/-72 versus 342+/-78 mg/dL, p < 0.02). Peripheral vascular disease was an independent predictor (p < 0.0001) of longitudinal FIB in stroke survivors. Of note, both WBC and PMN levels were chronically elevated in patients with stroke risk factors and in stroke survivors (p < 0.0001 for both) compared with healthy elderly subjects. CONCLUSIONS: Most acute-phase markers decline gradually after stroke, but FIB remains significantly elevated and is associated with increased risk for recurrent vascular events.  相似文献   
405.
Two groups of monoclonal antibodies (MAbs) specific to human cardiac troponin I (cTnI) were generated by immunization of mice by isolated cTnI (group I, 16 MAbs) or by the whole troponin complex (group II, 15 MAbs). Two sets of overlapping decapeptides covering the complete sequence of cTnI were prepared and used for epitope mapping by SPOT technique. Majority of MAbs (28 out of 31) interacts with synthetic peptides thus indicating that they recognize liner epitopes. MAbs raised against isolated cTnI preferentially recognize epitopes located at the N- or C-terminal ends of cTnI. Nine out of fifteen MAbs raised against whole troponin complex interact with epitopes located in the N-terminal part of cTnI. Generation of MAbs recognizing both isolated cTnI and cTnI inside of troponin complex and mapping their epitopes provides reliable detection of TnI in serum of patients with acute myocardial infarction.  相似文献   
406.
AIMS: There is little evidence to inform routine practice in the use of coronary angiography and revascularization procedures after acute myocardial infarction. Large differences in the uptake of these procedures have been reported but representative data are scarce. Outcome studies have produced opposing conclusions concerning the impact of the high rate of these cardiac procedures. METHODS AND RESULTS: A population-based patient sampling approach was utilized to identify routine practice in representative samples from 11 European countries. Data were collected retrospectively on treatment in the 6 months following acute myocardial infarction (n=2807). There was wide variation in utilization of coronary angiography and revascularization procedures. Even after restricting the analysis to patients <65 years (n=1262), there remained a 6 13 fold variation in the use of these procedures. A decreased likelihood of undergoing these procedures was associated with older age. In addition, there was an independent and negative association between female sex and utilization of coronary angiography and coronary artery bypass grafting (CABG). CONCLUSION: The effect on patient outcome of the observed variation in use of these procedures is not known but has important cost and resource implications for the health services. Outcome research is needed to define patient selection criteria and to measure the cost-utility of different angiography and revascularization rates.  相似文献   
407.
Giant Jungle Fowl previously were shown to be highly resistant to the onset of pulmonary hypertension syndrome (PHS, ascites) under conditions that induce a substantial incidence of PHS in broiler chickens. In the present study, lightly anesthetized, clinically healthy 12- to 13-wk-old male Giant Jungle Fowl maintained a lower respiratory rate, a similar hematocrit, and superior arterial blood gas values when compared with 6-wk-old male broilers. Giant Jungle Fowl weighed less than broilers (1,860 +/- 19 vs 2,788 +/- 63 g, respectively) and had equivalent absolute values for pulmonary arterial pressure, cardiac output, and pulmonary vascular resistance. Acute unilateral pulmonary artery occlusion in Giant Jungle Fowl doubled the pulmonary vascular resistance and forced the right ventricle to propel a sustained 60% increase in blood flow through the vasculature of the unoccluded lung. A transient increase in pulmonary arterial pressure initially was required to overcome the vascular resistance of the unoccluded lung; however, flow-dependent vasodilation gradually reduced the pulmonary vascular resistance and permitted pulmonary arterial pressure to return toward control levels. Unilateral pulmonary artery occlusion also triggered an immediate reduction in the partial pressure of oxygen in arterial blood, and the gradual return of pulmonary arterial pressure toward control levels did not eliminate this ventilation-perfusion mismatch, which has been attributed to blood flowing too rapidly through the unoccluded lung to permit diffusive gas equilibration. The inherent capacity for flow-dependent pulmonary vasodilation may reduce the susceptibility of Giant Jungle Fowl to PHS by reducing the increment in pulmonary arterial pressure required to propel an elevated blood flow through the lungs.  相似文献   
408.
409.
The effects of brain-derived neurotrophic factor (BDNF) were investigated on synaptic transmission and two forms of activity-dependent synaptic plasticity, long-term potentiation (LTP) and long-term depression (LTD), in visual cortex slices prepared from young (P21 -28) rats. The slices treated for 2-5 h in BDNF showed no difference from control slices when a 'strong' tetanus was used (theta-burst stimulation) to elicit a maximal level of LTP but displayed significantly greater synaptic potentiation in response to a 'weak' (20 Hz) tetanus. The BDNF-treated slices also showed significantly less LTD in response to a 1 Hz tetanus. Thus, BDNF treatment alters the relationship between stimulation frequency and synaptic plasticity in the visual cortex, shifting the modification threshold to the left. The effects of BDNF on LTP and LTD induction may be attributed to the significant enhancement of synaptic responses that was observed during conditioning stimulation. These data suggest that one role of BDNF during development of the visual cortex may be to modulate the properties of synaptic plasticity, enhancing synaptic strengthening and reducing synaptic weakening processes which contribute to the formation of specific synaptic connections.  相似文献   
410.
Our previous studies identified two iron-regulated cytoplasmic membrane proteins of 32 and 36 kDa expressed by both Staphylococcus epidermidis and Staphylococcus aureus. In this study we show by Triton X-114 phase partitioning and tritiated palmitic acid labelling that these proteins are lipoproteins which are anchored into the cytoplasmic membrane by their lipid-modified N termini. In common with those of some other gram-positive bacteria, these highly immunogenic lipoproteins were released from the bacterial cell into the culture supernatants, with release being promoted by growth of the bacteria under iron-restricted conditions. Immunoelectron microscopy with a monospecific rabbit antiserum to the 32-kDa S. epidermidis lipoprotein showed that the majority of the antigen was distributed throughout the staphylococcal cell wall. Only minor quantities were detected in the cytoplasmic membrane, and exposure of the lipoprotein on the bacterial surface was minimal. A monoclonal antibody raised to the 32-kDa lipoprotein of S. aureus was used in immunoblotting studies to investigate the conservation of this antigen among a variety of staphylococci. The monoclonal antibody reacted with polypeptides of 32 kDa in S. epidermidis and S. aureus and of 40 kDa in Staphylococcus hominis. No reactivity was detected with Staphylococcus lugdunensis, Staphylococcus cohni, or Staphylococcus haemolyticus. The gene encoding the 32-kDa lipoprotein from S. epidermidis has been isolated from a Lambda Zap II genomic DNA library and found to be a component of an iron-regulated operon encoding a novel ABC-type transporter. The operon contains three genes, designated sitA, -B, and -C, encoding an ATPase, a cytoplasmic membrane protein, and the 32-kDa lipoprotein, respectively. SitC shows significant homology both with a number of bacterial adhesins, including FimA of Streptococcus parasanguis and ScaA of Streptococcus gordonii, and with lipoproteins of a recently described family of ABC transporters with proven or putative metal ion transport functions. Although the solute specificity of this novel transporter has not yet been determined, we speculate that it may be involved in either siderophore- or transferrin-mediated iron uptake in S. epidermidis.  相似文献   
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