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101.
Objective— To determine outcome after medical or surgical treatment of postpartum mares with confirmed or presumptive uterine tears. Study Design— Case series. Methods— Postpartum mares were included if foaling had occurred within 7 days and uterine tear was confirmed surgically or, in medically treated mares, by palpation or presumed based on peritonitis. Information (age, breed; physical examination, laboratory and abdominocentesis findings; treatment, survival rates, length of hospital stay, treatments costs, and breeding performance after discharge) was obtained from the medical records (1990–2007). The influence of variables was compared between medical and surgical treatment, and between survivors and nonsurvivors. Results— For 49 mares, survival was 75%, with no significant difference between medical (11/15; 73%) or surgical (26/34; 76%) treatment. Admission variables, treatment cost, duration of hospital stay, and likelihood of foaling after discharge were not significantly different between treatment groups. Nonsurvivors were significantly more likely to have gastric reflux, higher heart rate, anion gap, lower total CO2, and leukocyte count, compared with survivors. Tears were significantly (P=.018) more likely to occur in the right uterine horn than in other parts of the uterus. Conclusions— Uterine tears occur more commonly in the uterine horns, more so the right horn, and survival is similar with surgical or medical treatment of uterine tears in postpartum mares. Clinical Relevance— Medical treatment may be a reasonable alternative to surgical treatment for uterine tears, although the severity of tear that can resolve with medical treatment is unknown, and medical therapy can be as expensive as surgical treatment.  相似文献   
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To determine the effects of poor maternal nutrition and litter size on foetal growth during mid‐gestation, pregnant ewes (n = 82) were fed 100%, 60% or 140% of NRC TDN beginning at day 30.2 ± 0.2 of gestation. Transabdominal ultrasound was performed weekly between day 46.0 ± 0.4 and 86.0 ± 0.7 to monitor foetal heart width (HW), umbilical diameter (UMB), rib width (RW) and placentome outer (OD) and inner diameter (ID). Data were analysed with repeated‐measures using the mixed procedure for effects of maternal diet, litter size and gestation, and equations predictive of gestational age were generated using the regression procedure. To determine the agreement of ultrasound measurement and actual size, ewes (n = 20–21) were euthanized at day 45 or 90 to obtain corresponding postmortem measurements for Bland–Altman analysis. The HW, UMB and placentome OD and ID increased with gestation (< .0001) but were unaffected by maternal diet or litter size ( .12). Ultrasound underestimated postmortem measurements of HW (14.8%), UMB (7.3%), placentome OD (4.5%) and ID (37.3%) at day 90 of gestation. Ultrasound underestimated RW at day 45 (7.7%) but overestimated RW (23.8%) at day 90, indicating inconsistent bias when reporting RW by ultrasound. Combining the HW, UMB, RW and placentome OD generated the strongest equation predictive of gestational age (R2 = .91). These findings indicate that during mid‐gestation, maternal diet or litter size did not affect HW, UMB or placentome diameters and these factors can be used to estimate gestational age.  相似文献   
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Early mortality of lambs is a major constraint on total productivity. In 6 different environments the early death rate varied from 12 to 30% of all lambs born. Cause of death differed among systems but only a proportion could definitely be ascribed to infectious disease: nutrition, management and other environmental factors also contribute to the mortality rate. Mortality can be reduced by isolating solutions due to any of these factors but best results (lowest death rates) would be obtained by an integrated package containing elements of all these aspects.  相似文献   
108.
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   
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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   
110.
Primary ciliary dyskinesia was diagnosed in three Newfoundland dogs with histories of chronic rhinitis and bronchopneumonia from an early age. Thoracic radiographs of two of them showed severe, dependent bronchopneumonia and right displacement of the cardiac apex but normal positioning of other organs. Histopathological examination of sections of lung from the other dog showed severe bronchopneumonia. A semen sample from one dog had a high percentage of spermatozoa with abnormal tails and poor progressive motility. Transmission electron microscopy of nasal brushings from all three dogs showed consistent ultrastructural defects in the cilia, including an absence of outer and inner dynein arms, disorganisation of peripheral doublets, occasional supernumerary doublets and singlets, and consistently disorganised basal bodies and foot processes; sections of trachea from one dog also had disorganised basal bodies. Pedigree analysis was consistent with a monogenic autosomal recessive pattern of inheritance for the defect. One dog is still alive, one dog died aged five years two months, and one dog was euthanased aged nine months. This is the first time primary ciliary dyskinesia has been reported in Newfoundland dogs.  相似文献   
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