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排序方式: 共有487条查询结果,搜索用时 31 毫秒
151.
蒙啤麦6号(原代号11PJ-005)为内蒙古自治区农牧业科学院作物育种与栽培研究所通过杂交育种培育的新品种,2019年9月通过非主要农作物品种登记审核。经品系鉴定、品系比较、区域试验及生产示范,均表现高产、优质、酿造品质好等特点。蒙啤麦6号属春性二棱皮大麦中熟品种,生育期66~90 d,株高56.0~84.4 cm,穗长7.1~7.5 cm,主穗粒数20~24粒/穗,千粒质量40.9~54.9 g,籽粒蛋白质含量11.7%。该品种中抗条纹病、网斑病,高感根腐病,抗倒性强,适宜在内蒙古及邻近省份春季种植。 相似文献
152.
艾比湖流域降水与径流变化特征分析 总被引:5,自引:1,他引:4
以艾比湖流域的博尔塔拉河(博河)和精河为例,基于1961-2008年的水文气象数据,运用Mann-Kendall非参数检验、线性倾向估计、小波分析等方法,分析流域内2条河流的变化趋势及周期特征,得到以下结论:(1)48年来,艾比湖流域博乐站和精河站降水量均呈现增加的趋势,其中,博乐站的线性倾向斜率为8.54mm/10年;精河站的线性倾向斜率为12.74mm/10年。(2)博河和精河年径流量均呈现极显著的增加趋势,其Z值分别为2.42和2.45,两者均通过а=0.05显著性检验。(3)艾比湖流域年降水量序列的小波系数等值线分布比较密集,存在明显的小波系数高低值中心震荡。两站年降水量在48年的时间序列中存在多个周期。(4)流域内2条河流均有明显的周期性变化,尤其以年代际周期最为显著。在每个周期中径流量又经历了几次"丰枯"交替。(5)博河和精河2条河流径流量与降水量的相关系数分别为0.564和0.490,均通过a=0.01的R显著性检验,表明降水是流域径流量的重要补给源之一。 相似文献
153.
S Akhter MS Ansari BA Rakha N Ullah SMH Andrabi M Khalid 《Reproduction in domestic animals》2011,46(1):45-49
This study was designed to compare the quality of liquid‐stored buffalo bull spermatozoa in soya lecithin based extender Bioxcell® (BIOX), milk (MILK), tris‐citric egg yolk (TEY) and egg yolk‐citrate (EYC) extender at 5°C. Semen was collected from five Nili‐Ravi buffalo (Bubalus bubalis) bulls of 6–7 years of age with artificial vagina over a period of 3 weeks (two consecutive ejaculates once in a week). Semen ejaculates having more than 60% motility were pooled, split into four aliquots, diluted (37°C; 10 × 106 motile spermatozoa/ml), cooled from 37 to 5°C in 2 h (0.275°C/min) and stored for 5 days. Sperm motility, viability, plasma membrane integrity (PMI) and normal acrosomal ridge were studied at first, third and fifth day of storage. Higher values of progressive sperm motility (%), sperm viability (%), sperm PMI (%) and normal apical ridge (%) were observed in BIOX, MILK and TEY extenders at first, third and fifth day of storage than EYC extender. Progressive sperm motility, sperm viability and sperm PMI in BIOX® extender were not different from MILK and TEY extenders at 1st and third day storage period. However, at fifth day of storage, the values for these parameters remained significantly higher (p < 0.05) in BIOX® compared with MILK, TEY and EYC extenders. At fifth day of storage, the semen quality parameters for Bioxcell® were comparable to those with MILK and TEY extenders at third day of storage. In conclusion, motility, viability and PMI of buffalo bull spermatozoa remained similar in Bioxcell®, milk and TEY extender at first and third days of storage at 5°C. Yet, the values for the aforementioned parameters in Bioxcell® were higher compared with milk, TEY and EYC extender at fifth day of storage at 5°C. 相似文献
154.
Anthony S. Brown BSc BVSc Frank N. Carrick BSc PhD Greg Gordon BSc PhD† Kira Reynolds BA ARMIT MIR‡ 《Veterinary radiology & ultrasound》1984,25(6):242-248
A radiographic technique, incorporating pneumoperitoneum, was developed to aid in identification of cyst-like structures in the reproductive tract of female koalas. These lesions, including pyometra and fluid-filled cysts associated with the upper reproductive tract, were viewed as radiopacities with clearly demarcated margins lateral to the caudal lumbar vertebrae. This technique provided a means of assessing with a high degree of reliability the incidence and distribution of this condition in various populations of koalas throughout eastern and southern Australia. A radiographic survey of 237 adult female koalas revealed a 43% (101/237) incidence of this condition, which is closely correlated with the lack of reproductive success observed in some populations of koalas in the wild. Although the etiology of this condition is little understood at present, the isolation of Chlamydia psittaci from the reproductive tracts of affected koalas, both male and female, is recorded. 相似文献
155.
LIN KLEIN VMD NANCY AILES BA GUSTAVE E. FACKELMAN DVM DiplomateACvs ELEANOR KELLON VMD HENRY ROSENBERG MD 《Veterinary surgery : VS》1990,18(6):479-482
Signs of malignant hyperthermia, including progressive increases in PaCO2 , skin temperature and heart rate, and elevated serum levels of potassium, inorganic phosphate, and creatine kinase, were identified in a halothane-anesthetized horse. Treatment was discontinuing halothane administration, applying ice and cold fluids, and hyperventilating with 100% oxygen. After an initial recovery, bilateral hindlimb myopathy and pigmenturia developed. The myopathy resolved after treatment with oral dantrolene, IV fluids, and hydrocortisone. Results of caffeine-halothane challenge, using semimembranosus muscle collected 2 weeks after the episode, were considered within normal limits for horses. The intraoperative abnormalities were evidently predictive of postanesthetic myopathy but the cause in this horse remained unclear. 相似文献
156.
157.
Leigh G. Griffiths BA VetMB DSAS MRCVS Martin Sullivan BVMS PhD DVR Diplomate ECVDI MRCVS Stuart W. J. Reid BVMS PhD MRCVS 《Veterinary surgery : VS》2001,30(4):359-365
OBJECTIVE: To compare the clinical effects of unilateral thyroarytenoid lateralization versus unilateral cricoarytenoid laryngoplasty for the treatment of canine laryngeal paralysis. Study Design-A prospective, clinical trial. ANIMALS: Twenty client-owned dogs admitted to Glasgow University Veterinary Hospital (GUVH) between 1997 and 1999 with a diagnosis of laryngeal paralysis. METHODS: A thorough evaluation of each dog was undertaken that included history, physical and neurologic examinations, complete blood count, serum biochemistry profile, serum thyroxine (T4) level, and thyroid-stimulating hormone (TSH) assay. The exercise tolerance of each dog was investigated by assessing respiratory rate and arterial blood gas analysis at rest and after 5 minutes of mild exercise. Animals were included in the study on the basis of a definitive diagnosis of laryngeal paralysis made by endoscopic observation of the larynx in the lightly anesthetized patient. The animals were randomly assigned to 1 of 2 treatment groups: unilateral thyroarytenoid lateralization or unilateral cricoarytenoid laryngoplasty, with all procedures being performed by the same surgeon. Video images of the rima glottidis were recorded pre- and postoperatively using video endoscopy. Video images were digitized and the area of the rima glottidis measured using image-analysis software. An increase in the area of the rima glottidis was expressed as a percentage of the preoperative area. All animals were reassessed 6 weeks' postoperatively, and exercise tolerance tests were repeated. RESULTS: The mean increase in the area of the rima glottidis postoperatively when compared with the preoperative area was 140% for those animals undergoing unilateral thyroarytenoid lateralization (range, 120%-158%) and 207% for those animals undergoing unilateral cricoarytenoid laryngoplasty (range, 183%-228%). This difference was statistically significant (P < .0001). At the 6-week postoperative examination, there was no significant difference in improvement between the 2 groups when compared on either a clinical basis or exercise tolerance tests. The mean surgical time in the 2 groups was 25 minutes for thyroarytenoid lateralization and 43 minutes for cricoarytenoid laryngoplasty. This was a statistically significant difference (P = .002). CONCLUSION: Although increase in area of the rima glottidis was significantly greater after unilateral cricoarytenoid laryngoplasty compared with unilateral thyroarytenoid lateralization, no difference in clinical outcome could be detected. However, the cricoarytenoid laryngoplasty procedure required significantly more surgical time. CLINICAL RELEVANCE: Both unilateral cricoarytenoid laryngoplasty and unilateral thyroarytenoid lateralization are successful methods for the treatment of laryngeal paralysis; however, thyroarytenoid lateralization requires less surgical time to perform. 相似文献
158.
为了解青藏高原高寒湖泊不同空间维度浮游植物群落优势种的生态位及种间联结性,本文选取青藏高原东南部最大的高寒冰山堰塞湖之一的巴松错为研究地点,于2020年7月对巴松错浮游植物进行了定性和定量采集,采集了水平和垂直维度浮游植物的水样275个,结合生态位宽度、生态位重叠值、生态响应速率、总体联结性、x2 检验、联结系数( AC) 、共同出现百分比( PC) 以及点相关系数(φ) 等方法,分析优势种的生态位及种间联结性。结果表明:1)共鉴定浮游植物优势种5属8种,均属于硅藻门;2)生态位宽度值差异较大,可分为三大生态位类群,且水平-垂直二维生态位宽度的变化幅度受水平维度生态位宽度影响比较明显;3)在水平维度上,生态位重叠度达到有意义的种对比例较高,具有明显的同质性;在垂直维度和水平-垂直维度上,生态位重叠度达到有意义的种对比例较低,具有明显的异质性;4)巴松错夏季浮游植物群落优势种生态响应速率在水平维度上形成正反馈,在垂直和水平-垂直维度维度上形成负反馈,表明巴松错夏季浮游植物群落存在群落多稳态,垂直和水平-垂直维度上群落较水平维度更稳定;5)巴松错夏季浮游植物群落总体处于演替的初期阶段且存在正向演替的趋势,物种间联结性不强,种间关系较为松散。本研究结果为进一步研究高寒湖泊优势种生态位和群落多稳态提供了基础资料。 相似文献
159.
Tenhagen BA Helmbold A Heuwieser W 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2007,54(2):98-102
The objective of this study was to analyse the effect of dystocia on calf viability, milk production, fertility and culling under field (farm) conditions in a retrospective case-control study. A total of 253 calvings that were attended by a veterinarian were classified into three categories: mild dystocia (MD), severe dystocia (SD) and caesarean section (CS). For every case of dystocia, a control was chosen from the same farm and matched for calving month, breed and parity. Cases and controls were compared concerning calf viability, milk production, fertility and culling. The proportion of stillbirths was significantly higher in cows with dystocia compared with their controls. However, the difference was lower in CS cows than in the other two groups. MD had no significant effects on milk production, fertility and culling. There were no obvious effects of SD on monthly test day milk production, while CS cows produced significantly less milk than their controls. Compared with controls, less SD (50.0% versus 61.6%) and CS cows (48.6% versus 70.3%) conceived until 200 days in milk and more CS cows (31.1% versus 16.2%) were culled in the same time interval. These data demonstrate the scope of economic and animal welfare opportunities associated with the reduction of dystocia by management and breeding. 相似文献
160.