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31.
This article describes and contrasts the public health response to two human rabies cases: one organ recipient diagnosed within days of symptom onset and the transplant donor who was diagnosed 18 months post‐symptom onset. In response to an organ‐transplant‐related rabies case diagnosed in 2013, organ donor and recipient investigations were conducted by multiple public health agencies. Persons with potential exposure to infectious patient materials were assessed for rabies virus exposure. An exposure investigation was conducted to determine the source of the organ donor's infection. Over 100 persons from more than 20 agencies spent over 2700 h conducting contact investigations in healthcare, military and community settings. The 564 persons assessed include 417 healthcare workers [5.8% recommended for post‐exposure prophylaxis (PEP)], 96 community contacts (15.6% recommended for PEP), 30 autopsy personnel (50% recommended for PEP), and 21 other persons (4.8% recommended for PEP). Donor contacts represented 188 assessed with 20.2% recommended for PEP, compared with 5.6% of 306 recipient contacts recommended for PEP. Human rabies cases result in substantial use of public health and medical resources, especially when diagnosis is delayed. Although rare, clinicians should consider rabies in cases of encephalitis of unexplained aetiology, particularly for cases that may result in organ donation.  相似文献   
32.
Populations of Mytilus edulis which were attached to the floats supporting the fish cages at the University of Tromsø's former experimental fish farm were found to have grown at a relatively high rate, and almost continuously. In contrast, mussels taken from other populations in the area which were not in the vicinity of any fish farm had grown more slowly and had marked growth-stoppage rings, probably laid down in winter. Mussels samples from a second fish farm in the area had grown at a rate similar to those from the University's fish farm. Possible reasons for the differences in growth rates among the populations sampled are discussed with reference to the possibilities of mussel farming in north Norway.  相似文献   
33.
Hepatic myelolipoma incarcerated in a peritoneopericardial diaphragmatic hernia was diagnosed in an 11-year-old, desexed female Persian cat. The cat was initially referred for investigation of tachypnoea and dyspnoea. Peritoneopericardial diaphragmatic hernia is a common incidental finding in cats and is usually asymptomatic. Myelolipoma is an extremely rare benign tumour, composed of extramedullary haematopoietic cells and adipose tissue. Myelolipomas are hypothesised to result from metaplastic alteration, rather than a neoplastic process, although this theory cannot be substantiated. The present case is only the fourth report of such an unusual occurrence in cats and displays significant differences to previous reports. Hepatic entrapment and burgeoning of the mass within the pericardial sac resulted in cardiac tamponade and overt signs of right-sided cardiac failure. Surgical intervention was successful and despite concerns regarding the cat's clinical presentation and the gross appearance of the lesion(s), a good long-term outcome is anticipated.  相似文献   
34.
The effect of ivermectin delivered from a sustained-release bolus (I-SRB) on the weight gain of beef cattle through a grazing season was evaluated using 20 yearling beef steer calves randomly divided into two groups of ten animals each. Calves in the control group each received a placebo bolus, while those in the treatment group each received an I-SRB designed to release 12 mg ivermectin day-1 for approximately 90 days. All animals were weighted and samples of feces were collected from the rectum at monthly intervals, beginning on Day 0, until trial termination (Day 148). Pasture larval counts were also conducted on herbage collected on each sampling date. On Day 119, two control and two treated calves were removed from pasture, housed in isolation for 3 weeks, then necropsied for recovery of gastrointestinal nematodes. Three sets of parasite-naive tracer calves were utilized to evaluate the initial, interim and final levels of pasture contamination by nematode larvae. A fourth set was used to evaluate the level of pasture contamination the following spring. The use of the I-SRB resulted in a greater than 99% reduction in fecal egg counts of trichostrongyles and numbers of gastrointestinal nematodes in the treated principals, as well as an average daily gain advantage of 0.114 kg over the 148 day period. A 67-98% reduction in pasture larval nematode contamination occurred on pastures grazed by the treated animals, as indicated by the parasite burden in tracer calves and pasture larval counts. The treatment effect was eventually lost by the following spring since tracer calves on the treated pasture had only 33% fewer nematodes than those on the control pasture.  相似文献   
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36.
OBJECTIVE: To estimate seroprevalence of bluetongue virus (BTV) and the geographic distribution of seropositive cattle herds in Illinois and western Indiana. SAMPLE POPULATION: 10,585 serum samples obtained from cattle in 60 herds during 3 transmission seasons (2000 through 2002). PROCEDURES: In a longitudinal study, serum samples were tested for BTV antibodies by use of a competitive ELISA. Four geographic zones were created by use of mean minimum January temperature. A multivariable mixed-effects logistic regression model with a random effect for herd was used to estimate seropositive risk for zone, age of cattle, herd type, and transmission season. RESULTS: Overall, BTV antibodies were detected in 156 (1.5%) samples. Estimated seroprevalence in 2000, 2001, and 2002 was 1.49%, 0.97%, and 2.18%, respectively. Risk of being seropositive for BTV was associated with geographic zone and age. Seroprevalence increased progressively from northern to southern zones, with no evidence of BTV infection in the northernmost zone. In the southernmost zone, annual seroprevalence ranged from 8.65% to 11.00%. Adult cattle were 2.35 times as likely as juvenile cattle to be seropositive. CONCLUSIONS AND CLINICAL RELEVANCE: Overall seroprevalence was lower than has been reported for Illinois cattle. Bluetongue virus antibodies were distributed heterogeneously in this region. Only in the southernmost zone was seroprevalence consistently > 2%. Regionalization of BTV risk based on state borders does not account for such variability. Serologic data could be combined with landscape, climate, and vector data to develop predictive models of BTV risk within transitional regions of the United States.  相似文献   
37.
The objective of this study was to understand the effects of fumarate addition on methane (CH4) and VFA production in the rumen through a meta-analysis of its effects on ruminal batch cultures. Because the reduction of fumarate to succinate can draw electrons away from ruminal methanogenesis, fumarate has been studied as a potential feed additive to decrease CH4 production in ruminants. The average decrease in CH4 in batch cultures was of 0.037 micromol/micromol of added fumarate, which is considerably lower than 0.25 micromol/micromol, the decrease predicted from the stoichiometry of the reactions involved. One reason that fumarate was not effective at decreasing CH4 in batch cultures was that only an average of 48% of added fumarate appeared to be converted to propionate. Secondly, the incorporation of reducing equivalents in the conversion of fumarate to propionate was almost entirely offset by their release from an average of 20% of added fumarate that appeared to be converted to acetate. Thermodynamic calculations indicated that the conversion of added fumarate to both propionate and acetate was feasible. Fumarate appears to be more effective in decreasing CH4 production and increasing propionate in continuous culture than in batch culture. This suggests that microbial adaptation to fumarate metabolism can be important. Variation in populations of fumarate-reducers, methanogens, and protozoa could all be involved. Fumarate supplementation for an extended period may result in the amplification of otherwise small populations of fumarate-reducers. Addition of some of these organisms may be helpful to improve fumarate conversion to propionate. Strategies based on enhancing the rumen's capacity to convert fumarate to propionate by maintaining a low fumarate concentration have been effective. Thermodynamic considerations should be taken into account when designing strategies for CH4 abatement through the addition of external electron acceptors.  相似文献   
38.
Summary Four inbred cabbage lines have been derived from a single parental plant through several generations of selfing. Two inbreds have been found homozygous for an S 1 allele while the other two are each homozygous for S 2. Each inbred is self-incompatible, cross-incompatible with the inbred carrying the same S allele, and fully cross-compatible with inbreds carrying the other S allele. The S 1 and S 2 pairs of inbreds were each found to consist of one inbred with very high self-incompatibility (mean seed set of 0.15–0.25 seeds per pod) and one inbred with less intense self-incompatibility (mean seed set of 1.25–1.70 seeds per pod). For the S 1 pair, flower to flower and plant to plant variation in seed set per pod was much larger for the less incompatible inbred that for the highly incompatible inbred. Further, incompatibility expression of the less incompatible inbred was influenced by temperature variation while that of the highly incompatible inbred was stable under different temperature regimes. The F1 between the two inbreds of high and low incompatibility with the common S 1 allele behaved like the less incompatible parent. F2 plants showed intermediate intensities of selfincompatibility as well as variation for both lesser and greater intensities than those exhibited by the parents. The variations of self-compatibility and the sensitivity to environmental differences are considered to be conditioned by genes which modify incompatibility expression of the S alleles.  相似文献   
39.
Inter-provenance hybrids of Pinuscaribaea var. hondurensis wereprogeny tested in Queensland, Australia inorder to assess the feasibility ofincorporating some desirable traits intothe local breeding population, consistinglargely of a single upland provenanceMountain Pine Ridge (MPR). Data onphenotypic traits up to seven years fromplanting revealed that an inter-provenancehybrid, MPR × coastal had greater diameter,straightness and wind-firmness, and fewerramicorns than the MPR control provenance.The data were mostly consistent for twowidely separated sites, and also whenpooled across those sites (p <0.05). In addition, hybrid vigor for treevolume was apparent (p < 0.05).Trees of coastal × Guanaja Island, and purecoastal provenances were as large as thoseof the MPR provenance but had fewerramicorns. Even though the coastal ×Guanaja provenance seemed to produce treesthat were more crooked than the MPRprovenance, there was evidence at leastwithin one site to suggest that the hybridtrees were superior in terms ofwind-firmness (p < 0.01). Breedingfor hybrid vigor and pedigree selection ofthe priority hybrid, MPR × coastal aresuggested as future measures. Pureprovenance populations of coastal andGuanaja island are to be bred as sublinesto the MPR breeding population for futureuse in inter-provenance hybridization andfor gene conservation.  相似文献   
40.
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