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排序方式: 共有823条查询结果,搜索用时 31 毫秒
1.
Ziyad Al-Kass Alexander Brown Anders Johannisson Theodoros Ntallaris Jane M. Morrell 《Reproduction in domestic animals》2021,56(6):848-856
Although single layer centrifugation (SLC) selects robust spermatozoa from stallion semen, the effect of individual variation has not been studied in detail. The objective of this study was to determine the variation among stallions in the effects of SLC on sperm quality during cooled storage for up to 48 hr. Semen samples from seven stallions (18 ejaculates) were split, with one portion being used for SLC and the other serving as a control (CON). Sperm quality (kinematics, reactive oxygen species (ROS) production, membrane integrity (MI) and chromatin integrity) were analysed at 0, 24 and 48 hr using computer-assisted sperm analysis and flow cytometry. Sperm quality was better in SLC than in CON at all timepoints, especially chromatin integrity and MI (p < .0001 for both), and some categories of ROS production (e.g. proportion of live hydrogen peroxide negative spermatozoa, p < .0001), but the degree of improvement varied among stallions and type of ROS (p < .05–p < .0001). Total and progressive motility were also better in SLC samples than in CON at 24 and 48 hr (p < .0001), although the effect on sperm kinematics varied. The interaction of treatment, time and stallion was not significant. In conclusion, sperm quality was better in SLC samples than in CON, although there was considerable individual variation among stallions. The improvement in sperm quality, particularly in chromatin integrity, was clearly beneficial, and therefore the use of this technique would be warranted for all stallion semen samples. 相似文献
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3.
American Animal Hospital Association;American Association of Feline Practitioners;AAHA/AAFP Pain Management Guidelines Task Force Members Hellyer P Rodan I Brunt J Downing R Hagedorn JE Robertson SA 《Journal of the American Animal Hospital Association》2007,43(5):235-248
Pain management in dogs and cats has undergone a dramatic evolution in the past decade. Current approaches focus on anticipation and prevention of pain, as well as both pharmacologic and nonpharmacologic management techniques. The veterinary team plays an essential role in educating pet owners about recognizing and managing pain in their pets. 相似文献
4.
Bianco D Armstrong PJ Washabau RJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):694-699
BACKGROUND: Glucocorticoids with or without other immunotherapy are the initial treatment of choice for dogs with severe immune-mediated thrombocytopenia (IMT). The majority of treated dogs will have improvements in platelet counts within 5 to 7 days of starting therapy, but complications from hemorrhage often occur before a response is seen. Human IV immunoglobulin (hIVIG) blocks Fc receptors on mononuclear phagocytic cells in dogs; it is used in people with idiopathic thrombocytopenic purpura. HYPOTHESIS: The purpose of this study was to describe adverse effects and benefit of hIVIG in addition to conventional immunosuppressive therapy in dogs with severe IMT. ANIMALS: Five client-owned dogs with severe primary IMT. METHODS: Case series. The hospital database was searched for dogs with primary IMT treated with hIVIG. RESULTS: No adverse effects were noted during or after hIVIG infusion in any treated dog. Over a 6-month follow-up, all dogs were clinically normal when using conventional immunosuppressive therapy. Human IVIG was administered 3 days after initiation of immunosuppressive therapy in 4 dogs, and, after 2 days, in 1 dog. In all dogs, the mean platelet counts pre- and 24 hours post-hIVIG infusion (0.28-0.76 g/kg) were 2,500/pL and 50,600/microL (62,750/microL for the 4 responders), respectively. One dog failed to respond as promptly to hIVIG (0.34 g/kg), and the platelet count increased to 66,000/microL after 9 days of immunosuppressive therapy. The mean duration of hospitalization post-hIVIG in all 5 dogs was 1.8 days (12 hours for responders), and the mean total length of hospitalization was 4.6 days (3.5 days for responders). Active hemorrhage resolved and no packed red blood cell transfusions were required after hIVIG infusion for responders. CONCLUSIONS AND CLINICAL IMPORTANCE: Human IVIG was well tolerated and appeared to be associated with rapid platelet count recovery and amelioration of clinical signs in most dogs with IMT. 相似文献
5.
da Silva Lima Renan Nunes Itaciara Larroza Block Jane Mara 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):63-69
Plant Foods for Human Nutrition - In this work, lycopene- and β-carotene-rich extracts were obtained from guava’s pulp and waste powders using maceration (ME), ultrasonic bath (BUAE,... 相似文献
6.
Jane Corliss Donald Lightner Zoula P. Zein-Eldin 《Aquaculture (Amsterdam, Netherlands)》1977,11(4):355-362
Two size groups of brown shrimp (Penaeus aztecus) were fed a formulated feed containing 0, 100, 1 000 or 5 000 mg of oxytetracycline/kg of feed. Growth and survival were measured after a 3-week drug consumption period. The shrimp were then inoculated with Vibrio alginolyticus, and survival was monitored during the following 24 h.At all three concentrations of oxytetracycline, small shrimp (mean initial wet weight 143.4 mg) consumed approximately one-third the amount of feed consumed by those fed the control diet with no oxytetracycline, yet growth was more rapid with diets containing 100 and 1 000 mg of oxytetracycline/kg of food than with the control diet. Larger shrimp (mean initial wet weight 458.1 mg) receiving oxytetracycline consumed about one-fourth the feed consumed by those on the oxytetracycline-free diet. Some growth inhibition was apparent in these shrimp at all oxytetracycline concentrations. Maximum drug consumption rate, based on actual feed intake, was approximately 1 300 mg oxytetracycline per kg body weight per day for small shrimp, but only 370 mg per kg body weight per day for larger shrimp.All shrimp fed 0, 100 or 1 000 mg of oxytetracycline/kg of feed died within 24 h following inoculation with a standard dose (70% light transmission at 520–540 nm) of Vibrio alginolyticus. All the small shrimp and 70% of the large shrimp fed at the 5 000-mg drug level died, but death generally took place later in the 24-h period than with those fed at the lower drug concentrations. All shrimp fed 5 000 mg oxytetracycline/kg of feed and inoculated with a 1 : 100 dilution of the standard dose of Vibrio alginolyticus survived. All small shrimp and 90% of the large shrimp survived injection of sterile saline. 相似文献
7.
Ai Y Medic J Jiang H Wang D Jane JL 《Journal of agricultural and food chemistry》2011,59(13):7385-7392
This study aimed to characterize and compare the chemical structures, physical properties, and enzymatic hydrolysis rates of five sorghum starches (6B73, 6C21, 6C69, 7R34, and X789) with that of corn starch (B73). Sorghum kernels consisted of 68.7-70.6% starch, more than the B73 corn (67.4%). Sorghum starches displayed higher gelatinization temperatures (66.6-67.4 °C), greater gelatinization enthalpy changes (13.0-14.0 J/g), and greater percentages of retrogradation (60.7-69.1%), but slower enzymatic hydrolysis rates (83.8-87.8% at 48 h) than the B73 corn starch (61.7 °C, 10.1 J/g, 51.5%, and 88.5%, respectively). These differences could result from the sorghum amylopectins consisting of fewer short branch chains (DP 6-12) (12.8-14.0%) than the corn amylopectin (15.0%). The sorghum starches showed greater peak and breakdown viscosities but lower setback viscosities than the B73 corn starch, resulting from the lower amylose content of the sorghum starches. After 96 h of fermentation, most ground sorghums exhibited lower ethanol yields (30.5-31.8%) than the ground B73 corn (31.8%). 相似文献
8.
植保无人机低空低量施药雾滴沉积飘移分布立体测试方法 总被引:2,自引:2,他引:0
随着植保无人机在中国的广泛使用,植保无人机的沉积分布均匀性与雾滴飘移流失也引起各方面的重视。目前,针对植保无人机施药雾滴沉积飘移的测试方法较少,且着重于从沉积或飘移中某一方面分析植保无人机雾滴沉积飘移规律,未对作业中全方位的雾滴的沉积飘失规律进行系统测试。该文基于国际标准ISO22866和ISO24253建了1套针对低空低量植保无人机的立体测试方法,分别在地面布置沉积和飘移收集器,在空中架设立体沉积和空中飘移收集器,结合航拍影像所获取的植保无人机准确作业参数,对4个型号植保无人机分别搭载德国Lechler公司的IDK120-015和TR80-0067喷头进行了测试,系统分析了无人机周边的总沉积以验证方法准确性,计算了总地面沉降以表征可利用部分和空中耗散以评估环境风险。结果表明,各植保无人机地面沉积率在53.6%~76.6%,地面飘移率最高17.4%,空中飘移率可高达14.7%;该测试系统可收集62.4%~101.7%无人机喷洒出的雾滴。测试的4种植保无人机在搭载IDK喷头后均明显降低了雾滴飘移,但也同时降低地面沉积率;各植保无人机在搭载2种喷头时沉积规律不同,不同植保无人机设计需要选择不同喷头。该测试方法能够有效的收集并分析植保无人机在作业区域的雾滴立体分布状态,可为植保无人机综合评估提供新的参考依据。 相似文献
9.
Soukaina Bouissil Claire Gurin Jane Roche Pascal Dubessay Zainab El Alaoui-Talibi Guillaume Pierre Philippe Michaud Said Mouzeyar Cdric Delattre Cherkaoui El Modafar 《Marine drugs》2022,20(2)
In many African countries, the Bayoud is a common disease spread involving the fungus Fusarium oxusporum f. sp. albedinis (Foa). The induction of plant natural defenses through the use of seaweed polysaccharides to help plants against pathogens is currently a biological and ecological approach that is gaining more and more importance. In the present study, we used alginate, a natural polysaccharide extracted from a brown algae Bifurcaria bifurcata, to activate date palm defenses, which involve phenylalanine ammonia-lyase (PAL), a key enzyme of phenylpropanoid metabolism. The results obtained showed that at low concentration (1 g·L−1), alginate stimulated PAL activity in date palm roots 5 times more compared to the negative control (water-treated) after 24 h following treatment and 2.5 times more compared to the laminarin used as a positive stimulator of plant natural defenses (positive control of induction). Using qRT-PCR, the expression of a selection of genes involved in three different levels of defense mechanisms known to be involved in response to biotic stresses were investigated. The results showed that, generally, the PAL gene tested and the genes encoding enzymes involved in early oxidative events (SOD and LOX) were overexpressed in the alginate-treated plants compared to their levels in the positive and negative controls. POD and PR protein genes selected encoding β-(1,3)-glucanases and chitinases in this study did not show any significant difference between treatments; suggesting that other genes encoding POD and PR proteins that were not selected may be involved. After 17 weeks following the inoculation of the plants with the pathogen Foa, treatment with alginate reduced the mortality rate by up to 80% compared to the rate in control plants (non-elicited) and plants pretreated with laminarin, which agrees with the induction of defense gene expression and the stimulation of natural defenses in date palm with alginate after 24 h. These results open promising prospects for the use of alginate in agriculture as an inducer that triggers immunity of plants against telluric pathogens in general and of date palm against Fusarium oxysporum f. sp. albedinis in particular. 相似文献
10.
Jane Oakey Judy Forbes-Faulkner Christopher Gilpin Bronwyn Murdoch Steven Johnson 《Journal of veterinary diagnostic investigation》2005,17(4):378-382
In 2003, a steer carcass was condemned at a Central Queensland abattoir because of metastatic tumors. In addition, a granulomatous lesion was found in the mediastinal lymph node. Histological examination showed this to be a pyogranuloma, typically associated with Rhodococcus or the Nocardia/Streptomyces group. However, in this case, the only etiological agent was an acid-fast bacillus, which would normally be associated with a more fibrous lesion. A number of nucleic acid-based techniques were used, and the isolate was identified as Mycobacterium asiaticum. This organism is a rarely encountered opportunistic pathogen of humans, associated with subtropical climates. This is the first report of this organism causing infection in cattle. The similarities between this case and cases of human disease are discussed. 相似文献