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991.
An 18-month-old, spayed female, mixed-breed dog was referred for investigation of persistent hypercalcemia. After extensive diagnostic evaluation, a tentative diagnosis of occult lymphosarcoma (LSA) was made and the dog was euthanized. At necropsy, infection with Heterobilharzia americana was diagnosed. In endemic areas, schistosomiasis should be included in the differential diagnosis of hypercalcemia, and a fecal examination should be performed in every dog with a hypercalcemia of unknown origin.  相似文献   
992.
We describe the draft genome of the microcrustacean Daphnia pulex, which is only 200 megabases and contains at least 30,907 genes. The high gene count is a consequence of an elevated rate of gene duplication resulting in tandem gene clusters. More than a third of Daphnia's genes have no detectable homologs in any other available proteome, and the most amplified gene families are specific to the Daphnia lineage. The coexpansion of gene families interacting within metabolic pathways suggests that the maintenance of duplicated genes is not random, and the analysis of gene expression under different environmental conditions reveals that numerous paralogs acquire divergent expression patterns soon after duplication. Daphnia-specific genes, including many additional loci within sequenced regions that are otherwise devoid of annotations, are the most responsive genes to ecological challenges.  相似文献   
993.
    
Objective: To report a case of femoral artery thrombosis and its medical management in a young dog. Case summary: A 13‐week‐old, female Boxer puppy presented with hind limb paralysis after an abdominal crush injury. A left femoral artery thrombus was identified on ultrasound. No spinal trauma was visualized in imaging studies. Clinical management of arterial thrombosis in a 13‐week‐old puppy with streptokinase and dalteparin therapy is described. New or unique information provided: This paper describes an unusual presentation of arterial thrombosis. The medical management with streptokinase and dalteparin is also out of the ordinary. Images that document the development of compensatory circulation around the thrombosed vessel are included. Additionally, this paper also documents the altered development that occurred in this immature dog after the thrombotic event.  相似文献   
994.
    
The oestrous cycle of four goats was monitored during the course of an infection with T. congolense maintained with sub-curative doses of diminazene aceturate. Four uninfected control goats also given diminazene aceturate acted as controls. Cyclical ovarian function was monitored by daily determination of plasma progesterone concentrations. According to plasma progesterone profiles, control goats continued to cycle throughout the experiment, completing 24 cycles in total. Mean (± SEM) cycle length in the control of goats was 21·1 ± 0·8 days, with mean plateau progesterone concentrations during the luteal phase averaging 8·95 ± 0·28 ng/ml.Three goats developed persistent corpora lutea following T. congolense infection. In two of these goats the luteal phase was extended for 48 and 94 days respectively, and the presence of corpora lutea on the ovaries confirmed at autopsy. In the third goat, the persistent corpus luteum regressed spontaneously after an extended cycle of 53 days. After a short 6 day cycle this goat completed 2 oestrous cycles of normal length. Progresterone concentrations were reduced by approximately half during the period of extended luteal function in the 3 infected goats with persistent corpora lutea. The fourth infected goat continued to cycle throughout the experiment, but also exhibited reduced progesterone concentrations in the cycle following infection.  相似文献   
995.
    
Morphological changes in the embryos, egg size and development, incubation period and morphological structures of newly hatched zoea of three mud crab Scylla species were determined. The three species exhibited similar embryonic development composed of 10 stages. The mean egg diameter of Scylla serrata was significantly larger (P<0.05) at the prehatch stage. The mean egg diameters of Scylla tranquebarica and Scylla olivacea were similar (P>0.05). The incubation period was the longest in S. serrata and the shortest in S. olivacea. There was a positive relationship between egg size and larval size, as S. serrata exhibited the largest egg size and first zoea. However, no correlation was detected between egg size at prehatch and lengths of the morphological structures of the newly hatched zoea. The three species exhibited similar lengths of cephalic structures, but S. olivacea had significantly shorter (P<0.05) abdominal structures. The duration of spawning from ablation was the shortest in S. tranquebarica and the longest in S. olivacea. The study is relevant to aquaculture and fisheries management of Scylla species.  相似文献   
996.
    
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997.
998.
    
Osmotic adjustment (OA) is considered as an important physiological mechanism of drought adaptation in many crop plants. The present investigation was aimed at assessing the importance of OA in improving productivity under drought. Using two automated rain-out shelters, 26 extra-short-duration pigeonpea [Cajanus cajan (L.) Millsp.] genotypes were grown with irrigation during the growth period or with water deficit imposed from flowering until maturity. Mean leaf Ψs100 (60–92 DAS) under drought correlated significantly (r2=0.72**; n=26) to the mean OA (60–92 DAS) and contributed 72% of the genotypic variation in OA. Significant genotypic variation was observed in the initiation of OA, the duration of OA and the degree of OA. Based on the measured OA at 72, 82, and 92 days after sowing (DAS), genotypes were grouped into five different clusters. Genotypic differences in total dry matter production under drought were positively associated with OA at 72 DAS (r2=0.36**, n=26). Significant positive relationship between OA at 72 DAS and grain yield under drought was found (r2=0.16*; n=26). However, OA towards the end of pod filling phase, i.e. at 92 DAS, had a significant negative relationship with grain yield under drought (r2=0.21*; n=26). Genotypic differences in grain yield under drought was best explained using stepwise multiple regression to account for differences in OA at 72, 82, and 92 DAS (r2=0.41**; n=78). The degree of OA at 72 and 82 DAS contributed positively to the grain yield, whereas OA at 92 DAS contributed negatively to this relationship.  相似文献   
999.
1000.
    
The purpose of this study was to investigate the response of horses to confinement and isolation in a stable (indoor individual housing) for the first time using behavioral indices, heart rate, and salivary cortisol concentration. Six naive 2-year-old Australian Stock Horse fillies were examined at 4-hour intervals over 24 hours in an outdoor group paddock followed by 24 hours in indoor individual housing. Behavioral observations and scores and heart rates were recorded and saliva samples were taken at each interval. During stabling, all horses became agitated and demonstrated increased vocalization and movement. Behavioral scores were significantly higher in the indoor individual housing (P < .001). No significant difference in heart rates between the two environments was detected. Mean salivary cortisol did not increase significantly (2 ng/mL ± 1.4 ng/mL in outdoor group paddock vs 2.5 mL ± 1.2 ng/mL in indoor individual housing). No diurnal rhythm in salivary cortisol was evident in either the outdoor group paddock or indoor individual housing. The results of this study highlight that a combination of behavioral and physiological measures allow better understanding of stress, where one measurement may be misleading. First time stabling of horses elicited marked behavioral responses indicative of stress that were not reflected in increased heart rates or salivary cortisol concentrations. The lack of a diurnal cortisol rhythm and the comparatively high basal cortisol concentrations found in the outdoor group paddock environment may imply that the fillies were already stressed; therefore, stabling did not cause further aberrations detectable by salivary cortisol analysis.  相似文献   
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