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751.
Doust RT Clarke SP Hammond G Paterson C King A 《Journal of the American Veterinary Medical Association》2006,228(3):389-391
CASE DESCRIPTION: A 4-month-old Bernese Mountain Dog was examined because of shifting hind limb lameness and lethargy of 2 weeks' duration. CLINICAL FINDINGS: The lameness was attributed to hypertrophic osteodystrophy. Portosystemic shunting was suspected on the basis of low serum albumin concentration and high serum bile acids concentration, and an intrahepatic shunt was identified ultrasono-graphically. Celiotomy was performed, and the shunt was partially closed with a cellophane band. During follow-up ultrasonography 7 months later, dilation of the left renal pelvis and proximal portion of the left ureter was identified. During exploratory celiotomy, the left ureter was found to pass dorsal to the caudal vena cava, and circumcaval ureter was diagnosed. TREATMENT AND OUTCOME: The ureter was transected, repositioned ventral to the vena cava, and anastomosed. Follow-up ultrasonographic examinations revealed gradual resolution of the hydronephrosis and hydroureter. CLINICAL RELEVANCE: Findings suggest that circumcaval ureter should be considered in the differential diagnosis for hydronephrosis and hydroureter in dogs. Partial obstruction of the middle segment of the ureter on ultrasonograms or contrast radiographs should increase the index of suspicion for this condition. 相似文献
752.
753.
Gonipterus scutellatus is a significant insect pest of eucalypts in most countries where that genus has been introduced, but is usually only of minor significance in its native Australia. Because of this, much of the research on its biology and host preferences has been done outside Australia. This fact has the potential to produce misleading results as the insect may be forced to choose less preferred hosts, if normally preferred species are unavailable. In part of its native range, in Tasmania, oviposition of G. scutellatus was recorded on seven naturally co-occurring Eucalyptus species that were planted in even aged, replicated plots. Among the seven species were the economically important species, E. globulus and E. viminalis, which have been previously reported as highly preferred hosts. Within plots, oviposition occurred most commonly on three peppermint species (E. pulchella, E. tenuiramis and E. amygdalina) and was rare or absent on the other species (E. globulus, E. viminalis, E. ovata and E. obliqua). Of the peppermints, E. pulchella was the most preferred species for oviposition at this site. A low percentage of peppermints in mixed forest (containing these seven species) immediately adjacent to plots was always matched by low numbers of G. scutellatus eggs within plots; but high percentages of peppermints outside plots could either be matched by high or low numbers of eggs within plots. In the discussion, we suggest that previous studies of G. scutellatus host range may have been limited because the insect was not exposed to hosts it naturally encounters. 相似文献
754.
Since the 1950s, pesticide resistance has been identified in many species. This paper considers the role of resistance action groups and notes that they were all formed in response to resistance problems occurring. Data now exist on the strategies which are most effective and the paper aims to bring together information from the fields of weeds, pests and diseases. Pesticide mixtures, sequences or rotations have been demonstrated as having a clear role in resistance management strategies. Resistance management would be improved if there was agreement on uniform test methodology and interpretation of results. The industry must work together to agree what constitutes an anti-resistance strategy, whether this is for prevention or cure, and to ensure that this is then included within regulatory frameworks. Future developments such as patch treatment, biotechnology and biocontrol are discussed. It is concluded that, to date, there has been little discussion between specialists in the field of resistance to herbicides, fungicides or insecticides and it is clear there are significant advantages to be had from more interaction. ©1997 SCI 相似文献
755.
J.M. Clarke B.A. Marchylo M.I.P. Kovacs J.S. Noll T.N. McCaig N.K. Howes 《Euphytica》1998,100(1-3):163-170
Canada was the largest durum wheat (Triticum turgidum var durum) producer in 1994, and in recent years supplied over 70% of
world export trade in durum. Breeding for pasta quality is, therefore, a primary objective in Canadian durum breeding programs.
Control of cultivar registration and stringent grading standards ensure that durum of consistent high quality is produced
for domestic and export markets. The objectives of breeding programs include: improvement of traits related to production
concerns, such as grain yield, disease resistance and sprouting resistance, and those related to end-use quality, such as
protein concentration and quality; milling quality factors, such as semolina yield; colour of the wheat, semolina and pasta;
and cooking quality. Selection and testing for quality begins at very early generations and becomes more stringent for advanced
inbred lines. Selection is practised at the F1 or F2, where appropriate, using monoclonal antibodies to identify desirable gamma gliadins (γ-45 ) or low molecular weight glutenin
subunits (LMW 2) that have been shown to be related to end-use quality. Grain from early generation yield trials, starting
at F4, is screened for protein concentration and pigment content by Near Infrared reflectance, and for gluten strength by sodium
dodecyl sulphate (SDS) sedimentation and micro-mixograph. Promising lines entered into multi-location yield trials are screened
with more time-consuming procedures to fully assess suitability for pasta processing. These tests include semolina yield,
ash and colour, and predictions of gluten strength such as mixograph and alveograph, and cooking quality. Candidate cultivars
with quality equal to or better than the mean of the check cultivars can be proposed for registration after three years in
the Durum Cooperative Test. It takes approximately 10 years from performing a cross to registrating a new cultivar.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
756.
Hanru Wang Xiaoxu Li Meiqing Wang Steven Clarke Mark Gluis Zeyu Zhang 《Aquaculture Research》2011,42(12):1816-1823
In this study, the effects of three commonly used chemicals, dimethyl sulphoxide (DMSO), ethylene glycol (EG), propylene glycol (PG) and their combinations with trehalose, were evaluated on the cryopreservation of D‐larvae of the blue mussel Mytilus galloprovincialis. The larvae were harvested 30 h post‐fertilization at 21 °C and cryopreserved using a standard protocol in 5%, 10% or 15% of DSMO, EG and PG either as single chemical solutions or in combination with 0.2 M trehalose. Among these cryoprotectants, 5% DMSO resulted in the highest post‐thaw survival rate of 55.3±7.8%, although it did not significantly differ from those with 10% and 15% EG. The addition of 0.2 M trehalose did not improve the post‐thaw larval survival rates in all the combinations assessed. The cryo‐effects on subsequent development were evaluated using the D‐larvae frozen with 5% DMSO. The results showed that cryopreservation affected both larval survival and growth in this species. The relative daily mortality rate was significantly higher in treated than control groups over the period from 3 h post‐thaw to day 11 post‐fertilization. On day 6 post‐fertilization, the average larval length in the treated group was significantly smaller than that in the control. From day 11 post‐fertilization, and onwards, differences in these two traits were not significant between treated and control groups. On day 21 post‐fertilization, about 80% of the larvae in both treated and control groups developed eyes and the normalized survival rate in the treated group was 12.5%. 相似文献
757.
The karyotype and chromosomal characteristics of the yellowtail kingfish Seriola lalandi lalandi were investigated by examining metaphase spreads from kidney cells of 4-month-old fish artificially bred using wild-captured broodstock from the coast of South Australia. A total of 80 mitotic metaphases from 10 individual fish were analysed, with 52 spreads having a mode of 2 n =48 chromosomes, representing 65% of the metaphases observed. The diploid consisted of two metacentric, two submetacentric, six subtelocentric and 38 telocentric chromosomes, with the fundamental number of chromosome arms being 52. The total haploid chromosome length was approximately 44.412 μm. This study shows that the karyotype of S. lalandi lalandi differs from those reported previously for other Seriola species in having one pair of metacentric chromosomes. 相似文献
758.
759.
760.
Clarke Alfred E. Edmundson W. C. Lombard P. M. 《American Journal of Potato Research》1941,18(10):273-279
American Journal of Potato Research - Spraying potato plants with dilute concentrations of a-naphthal-eneacetamide was not effective in increasing flower or seed ball production in the greenhouse... 相似文献