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441.
采用压片法对健蒜(Allium robustum)、多籽蒜(A. fetisowii)和新疆蒜(A. roborowskianum)3 种5 居群进行核型分析,结果表明,多籽蒜染色体数为2n = 2x = 20 和2n = 3x = 30,核型分类为2B 类;健蒜和新疆蒜染色体数均为2n = 2x = 16,核型分类均为2A 类。多籽蒜中裕民-塔城居群的核型公式为K(2n)= 2x = 20 = 12m + 7sm + 1st,裕民居群二倍体和三倍体核型公式分别为K(2n)= 2x = 20 = 12m +6sm + 2st 和K(2n)= 3x = 30 = 18m + 6sm + 6st。新疆蒜2 个居群的核型公式都为K(2n)= 2x = 16 = 12m +4sm。健蒜的核型公式为K(2n)= 2x = 16 = 14m + 2sm。健蒜的1 条m 染色体和新疆蒜奇台居群的1 条sm 染色体的短臂上有随体出现。不同种类的染色体相对长度组成存在差异,多籽蒜含L、M2、M1 和S染色体,新疆蒜缺失L 和S 染色体,健蒜缺失L 染色体。多籽蒜种内存在倍性分化,首次发现三倍体。  相似文献   
442.
AIM: To determine the role of the glycocalyx in microvascular permeability. METHODS: Dextran was intravenously injected and quatitatively examined in the rat transient cerebral ischemic model. At the same time, endothelial glycocalyx(anionic sites) was labelled with the probe cationic gold colloid(CGC) using post-embedding technique and examined with electron microscope. RESULTS: The labeling of CGC decreased significantly following ischemia, meanwhile, microvascular permeability to dextran increased. CONCLUSION:Endothelial glycocalyx is very sensitive to ischemia or anoxia. Its disruption may be the initiator of the dysfunction of endothelium and the determinant of increased permeability.  相似文献   
443.
目的 探讨影响HBV相关性慢加急性肝衰竭(HBV-ACLF)患者短期生存预后的危险因素并建立预后模型.方法 收集72例HBV-ACLF患者临床资料,根据90 d生存情况分为生存组(33例)和死亡组(39例),采用logistic回归分析危险因素,并构建预后预测模型.结果 死亡组年龄、中性粒/淋巴细胞比值及血清谷丙转氨酶...  相似文献   
444.
The objective of this study was to isolate bacteria on the skin of the proximal to distal equine limb to guide the practitioner in the selection of prophylactic antimicrobial protocols. This prospective study involved 20 client-owned horses that were admitted to the Veterinary Teaching Hospital for routine elective surgery. Each horse spent between 12 and 36 hours at our hospital before sampling. Samples were collected from the skin of the left mid-thorax and the dorsal aspect of nine joints on the left side of each horse: front and hind coffin and fetlock joints, carpi, elbows, shoulders, hocks, and stifles. Samples were cultured aerobically and speciated when possible. When evaluating bacterial composition by location, a 40% difference was considered clinically significant. When comparing proximal sites above the fetlock to distal sites, the odds of isolating gram-positive bacteria were 1.23 times (P = .0124) higher at proximal sites; the odds of isolating coliform bacteria were 1.32 times (P = .023) higher at distal sites; and the odds of isolating a common septic arthritis pathogen were 1.16 times (P = .018) higher at distal sites. Coagulase-positive Staphylococcus was not isolated in this study. All comparisons between sites and between the proximal and distal limb were <40%, and thus were not considered clinically significant. No coagulase-positive Staphylococcus was isolated from any of the 200 sites in this study, suggesting that iatrogenic infections by that organism may not be because of preexisting flora. These data suggest that antibiotic prophylaxis targeting preexisting normal flora should be similar regardless of the area of interest on the limb.  相似文献   
445.
为了研究同品种绵羊在不同放牧环境下的牧食行为差异,在典型草原区沙质草地和高平原草地两种放牧环境下,对四品种双杂交杂种绵羊的牧食行为进行了观察.结果表明:不同放牧环境下绵羊的采食时间和游走时间占放牧时间的80%左右,放牧环境对采食行为有显著的影响.绵羊在沙质草地采食和游走时间占总放牧时间的66.54%和15.63%,在高平原草地为77.49%和7.79%.不同放牧环境下卧息、站立等时间存在显著差异.  相似文献   
446.
[目的]犏牛可以生活在海拔2 800~4 200 m,对高寒缺氧的生态环境具有很强的适应能力,是“世界屋脊”的著名牛种,为了提高西藏犏牛资源的综合利用,其后代变废为宝。[方法]在试验区选择200头经产母犏牛通过引进安格斯牛的细管冻精,依靠人工授精技术,应用种间三元杂交技术生产优质商品肉牛试验,测定初生、3月龄的体重、体尺指标,观察高寒气候的适应性。[结果]结果显示:参配母犏牛200头,实配160头,其中104头母犏牛怀孕受胎,98头顺利产犊。实配率80%,人工授精受胎率65%,成活率94.23%。犏牛平均妊娠期(266.81±11.93) d。安格斯与西藏犏牛杂交后代的出生体尺、体重与传统杂交犊牛(多勒)相比,平均体重增加8.95 kg,提高73.23;体高、体斜长、胸围、管围平均分别比传统杂交犊牛(多勒)增加7.491 cm,1.394 cm,8.998 cm,0.063 cm,提高了13.94%,2.56%,15.70%,0.068%。安格斯与西藏犏牛杂交后代的3月龄与传统杂交犊牛(多勒)相比,平均体重增加43.3 kg,提高168.89;体高、体斜长、胸围、管围平均分别比传统杂交犊牛(多勒)增加15.67 cm,16.95 cm,26.31 cm,1.64 cm,提高23.27%,24.76%,34.31%,15.83%。[结论]弥补了犏牛传统杂交后代普遍存在的体躯发育差、生长发育慢等缺陷,且很好地适应西藏高寒生态环境和管理条件,杂种优势十分明显,因此安格斯牛可作为高原环境下繁殖犏牛生产肉牛的理想父本品种使用,并拥有开发高端产品的巨大潜力。  相似文献   
447.
448.
Stephan  Kaiser  DVM  MS  Daniel  Cornely  MD  Werner  Colder  MD  PhD  Michael T.  Garner  BA  CVM  K.-J. Wolf  MD  PhD  Helmut  Waibl  DVM  PhD  Leo  Brunnberg  DVM  PhD 《Veterinary radiology & ultrasound》2001,42(2):113-118
Measurements from magnetic resonance (MR) images can be used to examine the anteversion angle (AT-angle) and its influence on the lateromedial or mediolateral luxating forces on the patella. The AT-angle of the femoral neck was measured with the aid of MR imaging in 45 pelvic limbs without patellar instability, in 33 limbs with patellar luxation and in 6 limbs with rupture of the cranial cruciate ligament. The limbs with medial patellar luxation were divided into three groups based on clinical examination. The mean (range) AT-angle was 7.6 degrees (0 degrees to 24 degrees) in the "normal" group, 8.6 degrees (-10 degrees to 29 degrees) in the group "grade II," and -0.4 degrees in the group "grade III" (-28 degrees to 12 degrees). A mean (range) AT-angle of 4.8 (-4 degrees to 11 degrees) was measured in the pelvic limbs with rupture of the cranial cruciate ligament. Compared to literature that described AT-angles based on radiographs of normal limbs, reduced AT-angles were found in this study due to different lines of measurement of the femoral neck. This study documents that the AT-angle of the femoral neck does not influence patellar instability. This study also demonstrates that MR images can be used to make exact measurements of the canine AT-angle that represent the true anatomy of the femoral neck.  相似文献   
449.
Alterations in Carbohydrate Metabolism in Canine Lymphoma   总被引:1,自引:1,他引:1  
Following an overnight fast, blood samples were obtained from 14 dogs with previously untreated lymphoma before and 5, 15, 30, 45, 60, and 90 minutes following an intravenous challenge with 500 mg/kg dextrose. Samples were assayed for glucose, lactate, and insulin concentrations and compared statistically with ten control dogs of similar weight and age undergoing an identical dextrose challenge. Dogs with lymphoma had similar glucose tolerance curves when compared with controls. Lactate concentrations were significantly higher (P less than 0.001) at baseline and all time periods of the glucose tolerance test in dogs with lymphoma when compared with controls. Rise in lactate concentrations over baseline levels in the first 30 minutes of the glucose tolerance test were significantly higher in dogs with lymphoma (P = 0.011). Insulin concentrations were significantly higher (P less than 0.001) at baseline and at the 5-, 45-, 60-, and 90-minute time periods of the glucose tolerance test in dogs with lymphoma. Rise in insulin concentrations over baseline in the first 5 minutes of the glucose tolerance test were also significantly greater in dogs with lymphoma (P = 0.021). These results indicate carbohydrate metabolism is altered in dogs with lymphoma. Many of these alterations parallel those observed in human patients suffering from cancer cachexia making canine lymphoma a potential model for further study of the pathogenesis and therapy of cancer cachexia.  相似文献   
450.
Objectives— To determine interobserver repeatability of measurements on computed tomography (CT) images of lax canine hip joints at different ages and in the presence of degenerative joint disease at maturity. Study Design— Longitudinal observational investigation. Animals— Sibling crossbreed hounds. Methods— Pelvic CT was performed at 20, 24, 32, 48, 68, and 104 weeks of age. Measures were performed on 3 contiguous two‐dimensional (2D) transverse CT images of both hips at each time point by 3 investigators. Center‐edge angle (CEA), horizontal toit externe angle (HTEA), ventral (VASA), dorsal (DASA), and horizontal (HASA) acetabular sector angles, acetabular index (AI), and percent femoral head coverage (CPC) were measured. Interobserver repeatability was quantified with the intraclass correlation coefficient (ICC). Satisfactory repeatability was considered when ICC≥0.75. Results— DASA, CEA, and CPC were repeatable in all age groups. HASA and HTEA were repeatable for all but 1 time point. At 20 weeks of age, all measures but AI were repeatable, and at 104 weeks of age, DASA, CEA, CPC, and HASA were repeatable. Measures were repeatable in hips with and without degenerative changes with the exceptions of AI and HASA in normal hips and VASA and HTEA in osteoarthritic hips. Conclusions— Most 2D CT measurements examined were repeatable regardless of age or joint disease. Clinical Relevance— Two‐dimensional CT measures may augment current techniques for assessing joint changes in lax canine hips.  相似文献   
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