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41.
Samples of inbred lines of Hordeum vulgare produced by pedigree inbreeding, doubled haploidy and single seed descent have been compared for a range of agronomic characters. Differences between the means of the in bred s produced by single seed descent and pedigree breeding were due to differing levels of inbreeding. The present study confirmed chat recombinant inbred families which out-perform the higher scoring parent may be produced by either method. Caution should, however, be exercised when simply inherited characters controlled by major genes are fixed in early generations. Differences between the doubled haploid and single seed descent samples for the character thousand grain weight were attributable to coupling linkages involving epistatic genes. The production and evaluation of random inbred lines should be considered as an alternative to pedigree methods of barley breeding. 相似文献
42.
Allyson C. Berent DVM Jeffrey Todd DVM Jennifer Sergeeff DVM DACVIM Lisa L. Powell DVM DACVECC 《Journal of Veterinary Emergency and Critical Care》2005,15(2):128-135
Objective: To describe diagnostics, therapy, and sequelae of acute carbon monoxide (CO) toxicity because of a motor vehicle generator in 4 dogs and 2 cats. Series summary: Four dogs and 2 cats presented for recumbency, disorientation, dyspnea, and stiffness after an estimated 6–8 hour exposure to exhaust from a generator. Diagnostics included a serum carboxyhemoglobin levels evaluation, arterial blood gas analysis, pulse oximetry readings, and blood pressure measurements. Initial therapy included oxygen (O2) administration, intravenous bronchodilators, fluids, and a hemoglobin‐based O2 carrying (HBOC) molecule. Following administration of the HBOC, 4 of the 6 animals showed dramatic clinical improvement. Two weeks after hospital discharge, the owner reported potential hearing deficits in all animals. Brain auditory evoked response (BAER) tests were conducted in all surviving animals and some degree of hearing impairment was documented in all cases, with complete clinical resolution noted 6 weeks later. Unique information provided: This report describes the therapeutic use of an HBOC in acute isolated CO toxicity (i.e. without the complications of smoke inhalation). In addition, delayed nervous system dysfunction was documented in all surviving animals. 相似文献
43.
Fontenelle JP Powell CC Hill AE Radecki SV Lappin MR 《Journal of Feline Medicine and Surgery》2008,10(1):41-46
Bartonella henselae has been implicated as a causative agent of chronic uveitis in people and in some cats. The objective of this study was to determine whether Bartonella species seroprevalence or titer magnitude varies among cats with uveitis, cats without ocular diseases recorded and healthy cats, while controlling for age and risk of flea exposure based on state of residence. There was no difference in seroprevalence rates or titer magnitude between cats with uveitis and cats with non-ocular diseases. Healthy cats were more likely to be seropositive for Bartonella species than cats with uveitis. The median Bartonella species titer was 1:64 for all groups, although healthy cats were more likely to have higher titers than cats with uveitis and cats with non-ocular disease. The results suggest that serum antibody tests alone cannot be used to document clinical uveitis associated with Bartonella species infection. 相似文献
44.
Amara H. Estrada Herbert W. Maisenbacher III VMD Robert Prošek DVM MS Jesse Schold PhD Melanie Powell BS James M. VanGilder BS 《Journal of Veterinary Cardiology》2009,11(2):79-88
Objective
To compare left ventricular synchronization and systolic performance with transvenous pacing of the right ventricular apex (RVA), left ventricular free wall (LVF) or simultaneous pacing of the RVA and LVF (BiV).Animals, materials and methods
Seven canine patients with complete heart block. Prospective study evaluating effect of pacing site. Twenty four hours following implantation of transvenous BiV pacing systems, electrocardiograms and echocardiograms were assessed during pacing from the: (1) Right Atrial Appendage/RVA (RAA/RVA), (2) RAA/LVF, and (3) RAA/BiV.Results
QRS duration was significantly shorter with BiV pacing versus LVF pacing (p < 0.001), or RVA pacing (p < 0.001). Echocardiographic indices of systolic performance fractional shortening (FS), ejection fraction (EF), cardiac output (CO) were significantly higher with BiV pacing than with pacing from the RVA (P = 0.023, 0.006, and 0.002 respectively). Cardiac output, measured by the biplane Simpson's method, was higher with LVF versus RVA pacing (P = 0.036). There was no difference in FS or EF when comparing LVF to RVA pacing. Tissue Doppler measurements of synchronization and systolic performance did not show any difference between pacing mode, but a significantly increased number of segments were seen to contract following aortic valve closure during LVF pacing (P = 0.0268) and RVA pacing (P = 0.0197) as compared to BiV pacing.Conclusions
Findings suggest that BiV pacing improves cardiac output and systolic performance versus RVA pacing. This improvement however, is not reflected in tissue Doppler indices of synchronization and systolic performance. 相似文献45.
Catherine R. Back Henry L. Stennett Sam E. Williams Luoyi Wang Jorge Ojeda Gomez Omar M. Abdulle Thomas Duffy Christopher Neal Judith Mantell Mark A. Jepson Katharine R. Hendry David Powell James E. M. Stach Angela E. Essex-Lopresti Christine L. Willis Paul Curnow Paul R. Race 《Marine drugs》2021,19(2)
To tackle the growing problem of antibiotic resistance, it is essential to identify new bioactive compounds that are effective against resistant microbes and safe to use. Natural products and their derivatives are, and will continue to be, an important source of these molecules. Sea sponges harbour a diverse microbiome that co-exists with the sponge, and these bacterial communities produce a rich array of bioactive metabolites for protection and resource competition. For these reasons, the sponge microbiota constitutes a potential source of clinically relevant natural products. To date, efforts in bioprospecting for these compounds have focused predominantly on sponge specimens isolated from shallow water, with much still to be learned about samples from the deep sea. Here we report the isolation of a new Micromonospora strain, designated 28ISP2-46T, recovered from the microbiome of a mid-Atlantic deep-sea sponge. Whole-genome sequencing reveals the capacity of this bacterium to produce a diverse array of natural products, including kosinostatin and isoquinocycline B, which exhibit both antibiotic and antitumour properties. Both compounds were isolated from 28ISP2-46T fermentation broths and were found to be effective against a plethora of multidrug-resistant clinical isolates. This study suggests that the marine production of isoquinocyclines may be more widespread than previously supposed and demonstrates the value of targeting the deep-sea sponge microbiome as a source of novel microbial life with exploitable biosynthetic potential. 相似文献
46.
Jeffrey M. Todd DVM Lisa L. Powell DVM DACVECC 《Journal of Veterinary Emergency and Critical Care》2007,17(3):286-289
Objective: To describe a case of xylitol intoxication causing fulminant hepatic failure in a dog. Case summary: A 2.5‐year‐old castrated male English Springer Spaniel weighing 26 kg, was presented after ingestion of half of a loaf of bread containing the sweetener xylitol. Toxic effects of the xylitol in this dog included vomiting, mild hypoglycemia and fulminant hepatic failure. Clinical management of acute hepatic failure and subsequent coagulopathy with supportive care and fresh frozen plasma is described. The dog was discharged 3 days after admission after a full clinical recovery. New or unique information provided: This paper describes the clinical consequence and successful treatment of fulminant hepatic failure in a dog following ingestion of xylitol. 相似文献
47.
Pasquarello A Petri I Salmon PS Parisel O Car R Toth E Powell DH Fischer HE Helm L Merbach A 《Science (New York, N.Y.)》2001,291(5505):856-859
We determined the structure of the hydrated Cu(II) complex by both neutron diffraction and first-principles molecular dynamics. In contrast with the generally accepted picture, which assumes an octahedrally solvated Cu(II) ion, our experimental and theoretical results favor fivefold coordination. The simulation reveals that the solvated complex undergoes frequent transformations between square pyramidal and trigonal bipyramidal configurations. We argue that this picture is also consistent with experimental data obtained previously by visible near-infrared absorption, x-ray absorption near-edge structure, and nuclear magnetic resonance methods. The preference of the Cu(II) ion for fivefold instead of sixfold coordination, which occurs for other cations of comparable charge and size, results from a Jahn-Teller destabilization of the octahedral complex. 相似文献
48.
D G Powell 《The Veterinary record》1975,96(2):30-34
During the past 20 years the equine population of Great Britain and Ireland has increased with the result that the practising veterinary surgeon is more frequently called upon to advise on equine problems. A significant portion of this advice is concerned with the examination of horses showing signs of this advice is concerned with the examination of horses showing signs of respiratory disease. Numerous pathogens, which include viruses, bacteria, parasites and moulds invade the respiratory tract causing similar signs of illness. It is therefore difficult to provide an aetiological diagnosis based on a clinical examination. Field studies supported by laboratory investigations have established that influenza and herpes viruses are frequently responsible for outbreaks of disease. Epidemiological studies suggest that other factors including the immune state of the equine population influence the distribution and severity of respiratory disease. The aetiology, diagnosis, treatment and control of equine infectious respiratory disease are discussed below. 相似文献
49.
The extent of genetic diversity and the genetic relationships among 94 coconut varieties/populations (51 Talls and 43 Dwarfs)
representing the entire geographic range of cultivation/distribution of the coconut was assessed using 12 pairs of coconut
micro satellite primers. A high level of genetic diversity was observed in the collection with the mean gene diversity of
0.647±0.139, with that of the mean gene diversity of Talls 0.703±0.125 and 0.374±0.204 of Dwarfs. A phenetic tree based on
DAD genetic distances clustered all the 94 varieties/populations into two main groups, with one group composed of all the Talls
from southeast Asia, the Pacific, west coast of Panama, and all Dwarfs and the other of all Talls from south Asia, Africa,
and the Indian Ocean coast of Thailand. The allele distribution of Dwarfs highlighted a unique position of Dwarf palms from
the Philippines exhibiting as much variation as that in the Tall group. The grouping of all Dwarfs representing the entire
geographic distribution of the crop with Talls from southeast Asia and the Pacific and the allele distribution between the
Tall and Dwarf suggest that the Dwarfs originated from the Tall forms and that too from the Talls of southeast Asia and the
Pacific. Talls from Pacific Islands recorded the highest level of genetic diversity (0.6±0.26) with the highest number of
alleles (51) among all the regions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
50.
Assessment of EST- and genomic microsatellite markers for variety discrimination and genetic diversity studies in wheat 总被引:22,自引:0,他引:22
Fiona Leigh Vince Lea John Law Petra Wolters Wayne Powell Paolo Donini 《Euphytica》2003,133(3):359-366
It is likely that in the near future sequence information from sequencing programmes and EST libraries will generate an abundance
of genic microsatellite markers. This study is focused on the assessment of their likely impact and performance vis-à-vis
their genomic counterparts. Microsatellites from two sources were used to assess the genetic diversity in 56 old and new varieties
of bread wheat on the UK Recommended List. A set of 12 microsatellite markers generated from genomic libraries and 20 expressed
sequence tag (EST)-derived microsatellites were used in the study, and the performance of both marker sets assessed. The EST-derived
or genic microsatellites delivered fingerprints of superior quality, amplifying clear products with few stutter bands. Diversity
levels as revealed bygenic microsatellites are similar to the few published results. The PIC values for the genic markers
were generally lower than those calculated for the genomic microsatellites, though advantages of both marker classes for variety
identification applications are discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献