Progesterone and Caspase-3 Activation in Equine Cyclic Corpora Lutea     

G Ferreira-Dias  L Mateus  AS Costa  S Solá  RM Ramalho  RE Castro  CMP Rodrigues 《Reproduction in domestic animals》2007,42(4):380-386

Soon after ovulation, the newly formed corpus luteum (CL) starts secreting progesterone (P(4)), necessary for implantation. The CL, an ovarian transient endocrine organ, undergoes growth and regression throughout its life span. The objective of this study was to evaluate if caspase-3 mediates cell death in the equine cyclic luteal structures and relate it to luteal endocrine function. Blood and luteal tissue were collected during the breeding season after slaughter from 38 randomly assigned cycling mares. Luteal tissues were classified as corpora haemorrhagica (CH; n = 7); mid luteal phase corpora lutea (Mid-CL; n = 17); late or regressing corpora lutea (Late-CL; n = 9) and corpora albicans (CA; n = 5). Plasma P(4) concentration, determined by radioimmunoassay, showed a significant increase from CH to Mid-CL (p < 0.001), followed by a decrease to Late-CL (p < 0.001) and CA (p < 0.001). Caspase-3 processing and poly (ADP) ribose polymerase (PARP) degradation were assessed by western blotting. Active caspase-3 was twofold increased in Mid-CL, Late-CL and CA as compared with CH (p < 0.05). Immunocytochemistry also showed a significant increase in caspase-3 expression in large luteal cells in all structures when compared with CH (p < 0.05). Consistently, the endogenous caspase-3 substrate, PARP, was markedly degraded from CH to CA (p < 0.05). In fact, the ratio of full-length to degraded PARP showed a significant decrease from CH to Mid-CL, Late-CL and CA (p < 0.05). Finally, the decrease in P(4) from Mid- to Late-CL coincided with no further increases in apoptosis. In conclusion, these results suggest that the effector caspase-3 of apoptosis, might play an important role during luteal tissue involution in the mare, even though its relationship with P(4) remains to be elucidated.  相似文献   

抓低改促高产求发展——双峰乡实施毛竹丰产经营的调查     

宋军华  钟日生 《江西林业科技》2001,(Z1)

双峰乡是中国“毛竹之乡”——宜丰县的毛竹重点产区.在对毛竹林的经营中,双峰乡通过全面规划、分类改造,改革机制、多种管理方式经营,建设样板、典型带动推广,以及基地建设与竹材深加工开发相结合等一系列措施,使这个“双料”的毛竹之乡真正发挥了资源优势,实现了毛竹丰产高效,促进了地方经济发展.调查总结了其成功的竹林经营管理经验,还介绍了向全县推广的措施方法.  相似文献   

Effect of breed of cattle on transmission rate and innate resistance to infection with Babesia bovis and B bigemina transmitted by Boophilus microplus     

RE BOCK  TG KINGSTON  AJ de  VOS 《Australian veterinary journal》1999,77(7):461-464

OBJECTIVE: To assess the effect of breed of cattle on the transmission rates of and innate resistance to Babesia bovis and B bigemina parasites transmitted by Boophilus microplus ticks. DESIGN: Groups of 56 purebred B indicus and 52 B indicus cross B taurus (50%, F1 generation) steers were placed in a paddock seeded with and also naturally infested with B microplus which were the progeny of females ticks fed on B taurus cattle specifically infected with a virulent isolate of B bovis. The cattle were placed in the infested paddock 50 days after seeding had started. PROCEDURE: Cattle were inspected from horseback daily for 50 days. Clinically ill cattle were brought to yards and assessed by monitoring fever, depression of packed-cell volume, parasitaemia and severity of clinical signs. Any animals that met preset criteria were treated for babesiosis. Blood samples were collected from all cattle on day 28, 35 and 42 after exposure and antibodies to Babesia spp and packed cell volume measured. RESULTS: All steers, except for one crossbred, seroconverted to B bovis and B bigemina by day 35 and 75% of the crossbred steers showed a maximum depression in packed cell volume of more than 15% due to infection with Babesia spp compared with only 36% of the B indicus group. Ten of the 52 crossbreds and 1 of the 56 B indicus steers showed severe clinical signs. Two of the crossbreds required treatment of which one died 2 weeks after initial treatment. CONCLUSIONS: Pure-bred B indicus cattle have a high degree of resistance to babesiosis, but crossbred cattle are sufficiently susceptible to warrant the use of preventive measures such as vaccination. Transmission rates of B bovis and B bigemina to B indicus and crossbred cattle previously unexposed to B microplus were the same.  相似文献   

Magnetic microstructure of magnetotactic bacteria by electron holography     

RE Dunin-Borkowski  MR McCartney  RB Frankel  DA Bazylinski  M Posfai  PR Buseck 《Science (New York, N.Y.)》1998,282(5395):1868-1870

Off-axis electron holography in the transmission electron microscope was used to correlate the physical and magnetic microstructure of magnetite nanocrystals in magnetotactic bacteria. The magnetite crystals were all single magnetic domains, and the magnetization directions of small superparamagnetic crystals were constrained by magnetic interactions with larger crystals in the chains. Shape anisotropy was found to dominate magnetocrystalline anisotropy in elongated crystals. A coercive field between 300 and 450 oersted was determined for one chain.  相似文献   

设施老汉瓜采后干制技术研究     

杜娟  热比古丽·哈力克  沙吾提·阿布拉江  廖新福 《农产品加工．学刊》2020,(4):30-32

以设施老汉瓜为试材,采用不同成熟度、前处理、预处理温度后进行干制,测定含水率、失重率、色差等指标变化。相同的干燥温度、时间条件下,6个成熟度、2种不同的前处理、5种预处理温度的设施老汉瓜的失重率、最终含水率、总色差值在干制期内变化不同。结果表明,不同成熟度的设施老汉瓜,干制期的预处理温度、前处理和烘制温度差距,影响老汉瓜在干制过程中水分的散失。采用不同处理方式至完全干燥,可溶性固形物含量11%的设施老汉瓜,瓜干失重率、含水率、瓜干总色差值ΔE变化略慢,较好地保持瓜干的品质,适宜于老汉瓜的加工。  相似文献   

Magnetic Collapse in Transition Metal Oxides at High Pressure: Implications for the Earth     

RE Cohen  II Mazin  DG Isaak 《Science (New York, N.Y.)》1997,275(5300):654-657

Magnetic collapse in transition metal ions is predicted from first-principles computations at pressures reached in the Earth's lower mantle and core. Magnetic collapse would lead to marked changes in geophysically important properties, such as elasticity and conductivity, and also to different geochemical behavior, such as element partitioning, than estimated by extrapolating low-pressure data, and thus change the understanding of Earth's structure and evolution. Magnetic collapse results from band widening rather than from changes in crystal field splitting under pressure. Seismic anomalies in the outer core and the lowermost mantle may be due to magnetic collapse of ferrous iron, dissolved in iron liquid in the outer core, and in solution in magnesiowustite in the lowermost mantle.  相似文献   

Rib osteomyelitis in three foals     

KM Neil  RE Charman  JR Vasey 《Australian veterinary journal》2010,88(3):96-100

Three foals aged between 21 and 44 days were presented for evaluation of pyrexia and lameness. Each had subcutaneous abscessation associated with osteomyelitis of a rib at the costochondral junction and pathological fracture of the affected rib; one foal had more than one rib affected. Other localised sites of infection included other sites of osteomyelitis, omphalophlebitis, uveitis, enterocolitis, and calcaneal bursitis. The subcutaneous abscessation and rib osteomyelitis was treated surgically in two foals. Salmonella typhimurium was isolated from the subcutaneous abscess in one foal and from the faeces of another. Two of the three foals were euthanased. Ultrasonography was a more useful modality than radiography for establishing the diagnosis of costal osteomyelitis.  相似文献   

林业病虫害防治工作中的问题及对策   总被引：2，自引：0，他引：2  

苏玉珍  热希 《内蒙古林业调查设计》2007,30(6):71-72,6

林业有害生物防治是国家减灾工程的重要组成部分,通过对乌拉特前旗林业有害生物防治工作存在问题的分析,提出了解决这类问题切实可行的对策措施。  相似文献   

Laryngeal paralysis in a Rottweiler with neuroaxonal dystrophy     

PF BENNNETT  RE CLARKE 《Australian veterinary journal》1997,75(11):784-786

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Alternative and Complementary Veterinary Medicine: A Holistic View of Functional Medicine.     

RE Clarke 《Australian veterinary journal》2001,79(11):777-777

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