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1.
Transected cranial cruciate ligaments in nine Holstein heifers were replaced with an autograft harvested from fascia on the medial surface of the gluteobiceps muscle and a connected segment of the lateral patellar ligament. There was minimal lameness at month 1, and all animals were sound by month 2. There was no evidence of degenerative joint disease in any stifles examined at necropsy on days 90, 120, or 365. Augmented healing of the severed cranial cruciate ligaments occurred in several animals. The mean failure strength of the cranial cruciate ligament replacements was 29.7% of the failure strength of the contralateral normal cranial cruciate ligament in four heifers. The technique was successful in eight of 13 bulls and cows with ruptured cranial cruciate ligaments. Animals treated successfully had significantly lower body weights than those with unsuccessful outcomes.  相似文献   
2.
Regimes of high abundance of sardine (Sardinops sagax and Sardina pilchardus) have alternated with regimes of high abundance of anchovy (Engraulis spp.) in each of the five regions of the world where these taxa co-occur and have been extensively fished. When one taxon has been plentiful, the other has usually been at a reduced level of abundance, and vice versa. Changes in the four heavily fished regions that support S. sagax–the Japanese, Californian, Humboldt, and Benguela systems–from a regime dominated by one taxon to a high level of abundance of the other have occurred more or less simultaneously. In the Pacific Ocean, sardines have tended to increase during periods of increasing global air and sea temperatures and anchovies to decrease. The Japanese system is dominated by sardines to a greater extent than the other systems, and sardines off Japan appear to increase as the Kuroshio Current cools. At the eastern edge of the Pacific Ocean, sardines colonize cooler areas during periods of warming. The Benguela system is out of phase with the three Pacific systems. The four systems all appeared to be in a state of flux in the 1980s. Increased abundance of the subdominant taxon is often one of the first signs of change. Sardines are relatively sedentary in refuge areas when scarce but change behavior to become highly migratory and colonize cooler areas when abundant. Anchovies, by contrast, expand around a fixed geographic center.  相似文献   
3.
The goals of our study were to review the ultrasonographic features of spontaneous extrahepatic biliary obstruction in cats and to determine whether these features can assist in differentiating tumor, inflammation, and choleliths as the cause of obstruction. Thirty cats with a presurgical ultrasound examination an dconfirmed extrahepatic biliary obstruction were studied. A common bile duct diameter over 5 mm was present in 97% of the cats with extrahepatic biliary obstruction. Gallbladder dilation was seen in < 50% of the cats. Ultrasound identified all obstructive choleliths (calculus or plugs) in the common bile duct. However, neither common bile duct diameter nor appearance or any other ultrasonographic feature allowed differentiation between tumor and inflammation as the cause of obstruction. A short duration of clinical signs (10 days or less) seemed to be associated with obstructive cholelithiasis.  相似文献   
4.
以干浸膏得率和黄芩苷提取率为考核指标,采用正交试验法对普抗合剂水提取醇沉淀制备工艺进行考察.普抗合剂最佳制备工艺方案为加水量10倍,提取2次,每次1 h,55%的乙醇沉淀杂质 .该工艺科学合理,适合于大规模工业生产.  相似文献   
5.
经过对兽药生产厂家和经营企业几年的整治,尤其是新<兽药管理条例>和<兽药标签和说明书管理办法>出台后,又经过GMP认证,兽药生产经营市场秩序和经营行为得到了一定的规范.但兽药使用环节中却存在诸多的问题,如:违法使用人用药品;违法使用禁用兽药;不执行休药期规定;未建立台帐等等.这些问题的存在,直接导致了动物产品的安全性问题.对此,笔者分析了兽药使用环节存在问题的原因,并对解决这些问题提出了个人观点.  相似文献   
6.
Simple complete dorsal fractures of the proximal phalanx were repaired in 2 mature pleasure horses with cortical bone screws placed in lag fashion. Healing occurred within 12 weeks and both horses returned to their previous performance level of light pleasure riding within 6 months of injury.  相似文献   
7.
Ten isolates of Trichoderma harzianum were tested for their ability to control lettuce seedling damping-off caused by introduced Rhizoctonia solani. T. harzianum isolates TRC 9 and 28 both reduced damping-off. Dual culture experiments were used to select isolates for the study of antibiotic production and mycoparasitism. T. harzianum isolate TRC 12 produced volatile and non-volatile antibiotics, whilst TRC 33 produced only non-volatile antibiotics. T. harzianum isolates 018-2/Y and TRC 9,15 and 28 mycoparasitized R. solani by coiling around and lysing the host hyphae. It appeared that mycoparasitism was more important than antibiosis in the biological control of damping-off.  相似文献   
8.
There is a need to simultaneously preserve evidence of interactions between the biological community and soil structural properties of a soil in as near an intact (natural) state as possible. Three dehydration techniques were implemented and assessed for their ability to minimise disruption of both biological and physical properties of the same arable soil sample. Dehydration techniques applied until samples were at constant weight were i) air-drying at 20℃ (AD); ii) -80 ℃ freeze for 24 h, followed by freeze-drying (-80FD); and iii) liquid nitrogen snap freeze, followed by freeze-drying (LNPD) and were compared to a moist control. Physical structure was determined and quantified in three dimensions using X-ray computed tomography and microbial phenotypic community composition was assessed using phospholipid fatty acid (PLPA) profiling. This study confirms that any form of dehydration, when preparing soil for simultaneous biological and physical analysis, will alter the soil physical properties, and cause some change in apparent community structure. Freeze-drying (both the LNFD and -80FD treatments) was found to minimise disruption (when compared to the moist control soil) to both the soil physical properties and the community structure and is a preferable technique to air-drying which markedly alters the size and character of the pore network, as well as the phenotypic profile. The LNFD was the preferred treatment over the -80FD treatment as samples show low variability between replicates and a fast turn-around time between samples. Therefore snap freezing in liquid nitrogen, followed by freeze drying is the most appropriate form of dehydration when two sets of data, both physical and biological, need to be preserved simultaneously from a soil core.  相似文献   
9.
[目的]通过对C型肉毒梭菌肉毒毒素的提取与鉴定,为类毒素和抗毒素的制备及抗原性分析奠定基础.[方法]将分离鉴定得到的C型肉毒梭菌通过扩大培养、产毒培养后将产生的肉毒毒素采用除菌过滤、硫酸铵盐盐析、离心、透析、浓缩的方法从产毒培养基中分离提取出来.再将提取的肉毒毒素通过SDS-PAGE鉴定毒素蛋白的分子量.[结果]分离出来的毒素蛋白重链和轻链分别在98和53 KDa左右,与C型肉毒毒素的理论分子量相符.[结论]提取的肉毒毒素是C型肉毒毒素.  相似文献   
10.
The drop-disc method of estimating herbage dry-matter production was evaluated for ryegrass from growth commencement to the silage stage; the latter typically corresponded to a maximum dry matter (DM) mass of almost 7 t ha−1. A close linear relationship ( r 2= 0·829) was found between disc settlement height and DM mass up to 4–5 t ha−1 for the period when growth was mainly vegetative rather than reproductive. During the latter stage, the presence of stems and the occurrence of lodging had a detrimental effect on the quality of disc calibration data. The technique was demonstrably useful in experiments as a cheap, rapid and trouble-free method for monitoring the initiation of grass production and rate of production during the vegetative stage.  相似文献   
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