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1.
Dental nerve blocks provide excellent pain management for many oral procedures. They are easy and inexpensive to perform, provide a rapid onset of action, and work in concert with anesthetic and other analgesic modalities. This article explains how to administer various dental nerve blocks and discusses the indications and precautions associated with their use.  相似文献   
2.
Contact neodymium:yttrium aluminum garnet (Nd:YAG) laser transscleral cyclophotocoagulation (TSCP) was performed on 23 eyes of 16 horses for treatment of glaucoma. The mean highest preoperative IOP was 51 ± 17 mmHg. Follow-up evaluation was available for 19 eyes 1 day after surgery, 14 eyes from 1 to 2 weeks, 16 eyes from 4 to 6 weeks, 9 eyes from 12 to 16 weeks, and 10 eyes greater than 20 weeks after laser treatment. The mean intraocular pressure (IOP) the day following surgery was 34 ± 13 mmHg. The mean IOP for each follow-up period was: one to two weeks postoperative, 23 ± 9 mmHg; four to six weeks, 24 ± 7 mmHg; 12–16 weeks, 28 ± 10 mmHg; and  20 weeks, 22 ± 9 mmHg. IOP measurements were significantly different from pretreatment values for all follow-up intervals except for weeks 12–16 ( P < 0.05). Treatment success was defined as maintenance of IOP < 30 mmHg. Treatment success was achieved in 93%, 88%, 78%, and 70% of the treated eyes at the 1–2 weeks, 4–6 weeks, 12–16 weeks, and the  20 weeks re-evaluation, respectively. No significant difference was found between the number of eyes visual at presentation (52.2%) and visual at 20 weeks (60%). The most common laser complications were conjunctival hyperemia (21.7%) and corneal ulcers (13.0%). Results of this study indicate that Nd:YAG TSCP is an effective method of controlling IOP and preserving vision in horses with glaucoma. An effective Nd:YAG laser protocol for TSCP in the equine glaucomatous eye is a power setting of 11 W, duration of 0.4 s, applied 5 mm posterior to the limbus at 60 sites, resulting in a total energy dose of 264 J.  相似文献   
3.
Finding cardiovascular disease genes in the dog   总被引:2,自引:0,他引:2  
Recent advances in canine genomics are changing the landscape of veterinary biology, and by default, veterinary medicine. No longer are clinicians locked into traditional methods of diagnoses and therapy. Rather, major advances in canine genetics and genomics from the past five years are now changing the way the veterinarian of the 21st century practices medicine. First, the availability of a dense genome map gives canine genetics a much-needed foothold in comparative medicine, allowing advances made in human and mouse genetics to be applied to companion animals. Second, the recently released 7.5× whole genome sequence of the dog is facilitating the identification of hereditary disease genes. Finally, development of genetic tools for rapid screening of families and populations at risk for inherited disease means that the cost of identifying and testing for disease loci will significantly decrease in coming years. Out of these advances will come major changes in companion animal diagnostics and therapy. Clinicians will be able to offer their clients genetic testing and counseling for a myriad of disorders. In this review we summarize recent findings in canine genomics and discuss their application to the study of canine cardiac health.  相似文献   
4.
The effects of origin of seed potatoes and the cropping history on the phenotypic structure of Phytophthora infestans populations was studied in northern Hessia, central Germany, from 2000 to 2002. Populations originating from fields with a history of potato cropping with only short or no rotation (old fields) were compared with populations from new fields, i.e., where no potatoes had been grown for at least 30 years and seed potatoes were either imported from breeders or produced on-farm (certified). The main goal was to determine the importance of seed potato infection in the establishment of new P. infestans populations. Isolates were characterized for mating type, virulences and rep- (repetitive extragenic palindromic) PCR fingerprints. Among a total of 639 isolates sampled from 31 sites, mating types A1 and A2 co-existed in all three years in 60–92% of the sites. Over all three years, 53 pathotypes were detected in a subsample of 272 isolates. Isolates originating from the new fields had significantly higher frequencies of the virulences v1, v2, v3, v6 and v7, indicating general effects of seed introduction into a new region. Thirty-six fingerprints were detected in a subsample of 281 isolates of which 22 were unique while four occurred in all three years and in many sites. Pathogen populations from potato fields that were grown from seed tubers of geographically different origin differed significantly based on χ 2 tests. While the Nei genetic distances were less than .1 among the local populations, distances to the US lineages US-1, US-6, US-7 and US-8 ranged from .22 to .47; however, the bootstrap values were not significant. Populations from old fields were more diverse and 14 of the 22 rep-PCR types occurred there among 132 isolates tested in comparison to six in the new fields (n = 140 isolates) and two among six isolates from volunteers. The results also suggest that both sexual and asexual reproduction play a role.  相似文献   
5.
ObjectiveTo characterize the impact of mechanical positive pressure ventilation on heart rate (HR), arterial blood pressure, blood gases, lactate, glucose, sodium, potassium and calcium concentrations in rattlesnakes during anesthesia and the subsequent recovery period.Study designProspective, randomized trial.AnimalsTwenty one fasted adult South American rattlesnakes (Crotalus durissus terrificus).MethodsSnakes were anesthetized with propofol (15 mg kg−1) intravenously, endotracheally intubated and assigned to one of four ventilation regimens: Spontaneous ventilation, or mechanical ventilation at a tidal volume of 30 mL kg−1 at 1 breath every 90 seconds, 5 breaths minute−1, or 15 breaths minute−1. Arterial blood was collected from indwelling catheters at 30, 40, and 60 minutes and 2, 6, and 24 hours following induction of anesthesia and analyzed for pH, PaO2, PaCO2, and selected variables. Mean arterial blood pressure (MAP) and HR were recorded at 30, 40, 60 minutes and 24 hours.ResultsSpontaneous ventilation and 1 breath every 90 seconds resulted in a mild hypercapnia (PaCO2 22.4 ± 4.3 mmHg [3.0 ± 0.6 kPa] and 24.5 ± 1.6 mmHg [3.3 ± 0.2 kPa], respectively), 5 breaths minute−1 resulted in normocapnia (14.2 ± 2.7 mmHg [1.9 ± 0.4 kPa]), while 15 breaths minute−1 caused marked hypocapnia (8.2 ± 2.5 mmHg [1.1 ± 0.3 kPa]). Following recovery, blood gases of the four groups were similar from 2 hours. Anesthesia, independent of ventilation was associated with significantly elevated glucose, lactate and potassium concentrations compared to values at 24 hours (p < 0.0001). MAP increased significantly with increasing ventilation frequency (p < 0.001). HR did not vary among regimens.Conclusions and clinical relevanceMechanical ventilation had a profound impact on blood gases and blood pressure. The results support the use of mechanical ventilation with a frequency of 1–2 breaths minute−1 at a tidal volume of 30 mL kg−1 during anesthesia in fasted snakes.  相似文献   
6.
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   
7.
In the Nordic countries, sets of Indicator (Signal) species, predominantly cryptogams, have been used as one measure to find forest stands which may harbour Red List species. Such data could potentially also be used to prioritise among stands for protection as nature reserves. We studied if the number of Signal species indicates the number of Red List species in oak-rich mixed forest in south Sweden. We also explored if species richness of the investigated groups is correlated with the number of Red List or Signal species. In 25 stands, we surveyed epiphytic and epixylic bryophytes and lichens, ground-floor bryophytes, and wood-living fungi. We studied correlations for two datasets; (1) all forest species and (2) deciduous forest specialists. When relating the number of Signal species to the number of Red List species for each taxon and in total, a significant correlation was found for temperate deciduous forest lichens. The number of Signal species was further significantly correlated to total species richness for lichens (all forest species) and for wood-living fungi (both datasets). The number of Red List lichens was correlated to total lichen richness (deciduous forest species). Signal species seem not to be unequivocal in prioritising potential reserves among valuable oak-rich woodlands and surveys by Red List species experts may be needed. Signal species may be more useful for finding relatively valuable sites in a matrix of production forest. Moreover, Signal species seem to be useful surrogates for total cryptogam species richness.  相似文献   
8.
A method for the detection of the effects of antibiotics on soil microbial communities was optimised in the present study. We investigated the influence of measurement time and nutrient status on the pollution-induced community tolerance (PICT), using the sulfonamide sulfachloropyridazine (SCP) as model compound. The tolerance development in soil microcosms that were exposed to SCP under different conditions was compared with the background tolerance in SCP-unexposed microcosms. The tolerance of bacterial extracts from the soil microcosms was determined in Biolog® multiwell plates as the SCP sensitivity of a range of physiological processes. The background tolerance was not affected by soil nutrient amendments, but an influence of the inoculum density in the microtiter plates was observed. Still, the variance of the background tolerance was low, which is in favour of the usage of community tolerance measurements for a selective detection of a toxicant impact. In line with the assumptions of the PICT concept, soil amendment with SCP led to an increase in community tolerance. This tolerance development was enhanced upon additional soil amendment with fresh pig slurry, and less by alfalfa meal addition. Tolerance increases were observed after a soil exposure to SCP of only 7 days, possibly because nutrient input facilitates the fast adaptation of the soil microbial community. However, a further increase in exposure time led to variable changes in the observed tolerance. Prolonged tolerance detection in the microtiter plates (11 days) enabled a clearer differentiation between different soil treatments, as it better resolved the EC50 values of processes with a high tolerance to bacteriostatic antimicrobial compounds. For the detection of antibiotic effects on soil microbial communities, it is therefore recommended to use nutrient amendments (possibly fresh pig slurry), to standardize the soil exposure time, and to extend the period of Biolog plate measurement beyond 7 days.  相似文献   
9.
A single IGF1 allele is a major determinant of small size in dogs   总被引:3,自引:0,他引:3  
The domestic dog exhibits greater diversity in body size than any other terrestrial vertebrate. We used a strategy that exploits the breed structure of dogs to investigate the genetic basis of size. First, through a genome-wide scan, we identified a major quantitative trait locus (QTL) on chromosome 15 influencing size variation within a single breed. Second, we examined genetic variation in the 15-megabase interval surrounding the QTL in small and giant breeds and found marked evidence for a selective sweep spanning a single gene (IGF1), encoding insulin-like growth factor 1. A single IGF1 single-nucleotide polymorphism haplotype is common to all small breeds and nearly absent from giant breeds, suggesting that the same causal sequence variant is a major contributor to body size in all small dogs.  相似文献   
10.
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