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811.
Oesophageal strictures in 2 horses with chronic recurrent oesophageal obstruction or choke was diagnosed by endoscopy and contrast radiography. Balloon dilation of the strictures was performed under endoscopic and fluoroscopic guidance. Follow‐up endoscopic and radiological examinations performed 6 weeks after the procedure showed clear dilation of the strictures. Both horses did not have any recurrence during follow‐up periods of 10 and 12 months.  相似文献   
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ESR2 is involved in oestrogen-related apoptosis in cell cycle spermatogenesis but their effects have not yet confirmed in pig. Therefore, this study was aimed to investigate the association of ESR2 polymorphism with sperm quality and boar fertility traits and to analyse the ESR2 mRNA and protein expressions in boar reproductive tissues. DNA samples from 203 Pietrain (PI) and 100 Pietrain × Hampshire (PIHA) pigs with records of sperm quality [sperm concentration (SCON), motility (MOT), semen volume (VOL), plasma droplet rate (PDR) and abnormal spermatozoa rate (ASR)] and fertility [non-return rate (NRR) and number of piglet born alive (NBA)] traits were available. A SNP in coding region of ESR2 g.35547A>G in exon 5 was associated with MOT and PDR in the PI and with SCON, VOL, MOT and PDR in PIHA population. For mRNA and protein expression study, a total of six boars were divided into two groups with group I (G-I) and group II (G-II) where G-I characterized for relatively a better sperm quality according to the mean of two groups. mRNA expression was higher in brain and testis than that in all parts of epididymis. Both qRT-PCR and western blot analysis revealed that the ESR2 gene expression and protein expression were significantly higher in testis collected from G-II compared with that of G-I boars. Moreover, ESR2 protein localization in germ cell, Leydig and Sertoli cells, epithelial cells and spermatozoa was remarkable, which indicated the important role of ESR2 in spermatogenesis process. These results might shed new light on the roles of ESR2 in spermatogenesis as candidate for boar fertility, but still the lack of association across populations should be considered.  相似文献   
817.
In this review, possible comparative advantages of studying endocrine disruption in farm animals vs laboratory rodents are discussed. First, using farm animals, the generality of findings in laboratory rodents are challenged. Farm animals may in certain aspects be better models for humans than laboratory rodents, and sometimes there might be methodological advantages in using farm animals. Second, there are several in vitro studies based on cell-culture systems from sows and cows where the effects of chemicals on sex steroid secretion can be measured and maturation and fertilization of oocytes may be assessed. These in vitro systems are powerful tools for dissecting the mechanisms of action for endocrine-disrupting chemicals. Third, in a set of recent in vivo studies using sheep, goats and pigs, in which very different exposure regimens to endocrine-disrupting chemicals have been used, a full panel of reproductive parameters pertinent to farm animals were assessed. Clinically, it is suggested that endocrine disruption in farm animals should be considered when impaired reproduction could be linked to change in source of feed or pasture. Finally, epigenetic and toxicogenomic approaches can be particularly rewarding in elucidating endocrine disruption in future farm animal studies.  相似文献   
818.
In a 7-week-old calf neurologic symptoms occurred after an accident in the feeding grid. The calf was alert but in left lateral recumbency. After having been placed on its right side it showed a sideward drift to the left. Following head movement, an asynchronous movement of the eyes could be observed. Lesions of the upper motor neuron system, N. vestibulocochlearis, Nn. oculomotorius, trochlearis and/or abducens as well as N. vagus were suspected. Radiological examination of the occipital region and cervical spine revealed an atlanto-occipital subluxation of the atlas. Based on all these findings, the diagnosis of traumatic atlanto-occipital dislocation was made and the calf was euthanized. The pathological findings confirmed this diagnosis.  相似文献   
819.
Fish have become a popular experimental model and companion animal, and are also farmed and caught for food. Thus, surgical and invasive procedures in this animal group are common, and this review will focus on the anesthesia and analgesia of fish. A variety of anesthetic agents are commonly applied to fish via immersion. Correct dosing can result in effective anesthesia for acute procedures as well as loss of consciousness for surgical interventions. Dose and anesthetic agent vary between species of fish and are further confounded by a variety of physiological parameters (e.g., body weight, physiological stress) as well as environmental conditions (e.g., water temperature). Combination anesthesia, where 2 anesthetic agents are used, has been effective for fish but is not routinely used because of a lack of experimental validation. Analgesia is a relatively underexplored issue in regards to fish medicine. However, recent studies have investigated opioid agents, nonsteroidal antiinflammatory drugs, and local anesthetics to determine their efficacy in minimizing pain and discomfort. The opioid morphine and the local anesthetic lidocaine do have significant effectiveness in reducing pain-related responses in rainbow trout (Oncorhynchus mykiss). Studies aimed at developing reliable analgesic protocols should explore a wide range of analgesic drug classes in several fish species.  相似文献   
820.
提升小波变换及其在信号去噪中的应用   总被引:8,自引:0,他引:8  
介绍了提升方法(1ifting Scheme)的基本原理,给出了用提升方法构造传统小波的实现方法,并将目前常用的小波转换成提升小波。同时还将提升小波应用到信号去噪中,并进行了数值仿真试验,结果表明,在去噪后信号的信噪比相近的情况下,提升小波与传统小波相比,其优点在于计算简单、编程容易、速度快。  相似文献   
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