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1.
通过本试验观察表明:黄皮[Clausena Lansium (Lour.)Skeels]的开花与温度有密切关系,温度高,开花过程短;温度低,开花过程长。花穗中的花轴增长速度也随温度升高而加快,花轴增长快,则花轴长,花穗大;反之,花轴增长速度慢,花轴短,花穗小。黄皮开花的顺序是从花穗基部第1—4个分枝开始,每个分枝则先从基部1—8个二次分枝首先开放。31℃是黄皮花粉萌发最适宜温度。在培养基中加入15—20%蔗糖或2.4—D,三十烷醇等生长调节物质,明显可提高黄皮花粉的萌发力。本试验对黄皮的物候期及植物学特性同时进行了研究。  相似文献   
2.
从理论上分析了错相及缺相判别原理,提出了新颖保护电路,其线路简单、实用。  相似文献   
3.
配置一定比例授粉树种,是提高授粉效果获得丰产的基础。授粉树比例幼龄期高于成龄期,授粉树花期应与天目蜜李基本一致、果形近似、品质好、抗性强的优良品种,这样才能确保果品的质量与产量。  相似文献   
4.
The effect of NaNO2 and NaCl on the growth of 24 lactic acid bacteria strains isolated from vacuum-packed cooked ring sausages were examined by analyzing different growth parameters with Bioscreen. NaNO2 had a very limited effect on the growth of lactic acid bacteria at 50 and 100 mg/l but at 400 mg/l a more pronounced inhibitory effect was found. Bacterial growth was enhanced by 1-2% (w/v) of added NaCl, while NaCl concentrations above 3% (w/v) had a clear inhibitory effect. Leuconostoc isolates seemed to be more sensitive to sodium nitrite and sodium chloride than homofermentative lactobacilli strains. Among homofermentative lactobacilli, the strains resembling Lactobacillus curvatus were more sensitive to NaCl than those resembling Lactobacillus sake.  相似文献   
5.
The discriminating ability of 15 parameters alone or in combinations, including results from analysis of plasma endotoxin, the Nycomed plasma D-Dimer test and phospholipase A2, were analyzed to predict morbidity and mortality in equine gastrointestinal colic. Endotoxaemia was a characteristic feature of the colic horses. The problem of adequately predicting non-survivors among colic horses required several parameters to be included in the logistic model: if the “classical parameters”, (heart rate, respiratory rate, PCV, anion gap) were included in the model, addition of plasma D-dimer, phospholipase A2, and Cl- significantly improved the predictive value of the logistic model. Increasing heart rate and D-dimer together with decreasing chloride was a risk factor for nonsurvival. The sensitivity of this three-parameter logistic model to predict nonsurvival was 78% and specificity 77%. The Nycomed D-Dimer test is recommended as a horse-site test to predict disseminated intravascular coagulation and nonsurvival in equine colic.  相似文献   
6.
本文提出了利用反相离子对色谱法,简单,快速,准确同时定量测定饲料添加剂中的烟酸,烟酰胺,盐酸吡哆辛,氰钴胺素,核黄素和硫胺素。样品前处理简单,六个维生素能在12min内获得满意的分离,各组份之间的分离度Rs大于1.60。各个维生素的回收率在87.0~101.0%,相对偏差为3.1~2.0%。色谱柱为LichrosorbRP-18 250×φ5mm,流动相为甲醇/水,0.25%TEA,1.25mmol/l PICB-5,3.75mmol/l PICB-7,pH3.00,紫外可变波长检测器采用MAXPL操作方式λ 1=254nm,λ_2=280nm,λ_3=354nm,流速1.1 nl/min。  相似文献   
7.
本文阐述了SS—1型声速实验仪的原理、结构和测量方法。波动学和分子物理学是物理学中的重要组成部分,"声速的测量"和"Y值的测量"两个实验有助于学生对波动相位的空间分布、谐振动的合成、李萨育图、能量按自由度均分原  相似文献   
8.
AIM: To explore the feasibility of direct separat and selective enlargement of the bone marrow-derived liver stem cells (BDLSC) from bone marrow cells with a culture system containing cholestatic serum in vitro. METHODS: Bone marrow cells of rats were cultured with selective media containing 2%, 5%, 7% and 10% cholestatic rat serum, respectively. The BDLSC were then induced to proliferate with the addition of hepatocyte growth factor (HGF) on the firth day. BDLSC were characterized using immunocytochemistry and RT-PCR for lineage markers, glycogen staining and urea synthetic assay for functions 2 weeks later. RESULTS: Bone marrow cells were unble to form colony in the presence of 2% cholestatic serum and apopotosis appeared gradually in 7% or 10% cholestatic serum. The BDLSC survived in the medium containing 5% cholestatic serum while the other types of cells did not. The survival cells proliferated with a high speed during the second week and then formed hepatocyte-like colony-forming units (H-CFU). Cells in the H-CFU expressed the characteristic proteins of fetal hepatocytes. Furthermore, they had glycogen storage and urea synthesis functions, two of the critical features of hepatocytes. CONCLUSION: The selective micro-environment effectively selected BDLSC from the bone marrow cell, and will be a new way to provide an abundant source of donor hepatocytes for clinical cell therapy.  相似文献   
9.
C-reactive protein concentrations in canine acute pancreatitis   总被引:1,自引:0,他引:1  
Objective: To determine if C‐reactive protein (CRP) concentration is elevated in spontaneously occurring canine acute pancreatitis (AP), and to measure changes in CRP during the course of hospitalization. Design: Prospective study. Setting: Tufts University School of Veterinary Medicine Foster Hospital for Small Animals. Animals: Sixteen client‐owned dogs with AP and 16 healthy controls. Interventions: Blood samples were obtained from the AP group on the day of diagnosis (Day 1), and on Days 3 and 5, unless the dog died or was discharged from the hospital. Blood was obtained from the control dogs once. Measurements and main results: Serum CRP was measured using a commercial immunoassay for each dog with AP and for healthy controls. Day 1 CRP concentrations were significantly higher in the AP group (56.1±12.7 μg/mL) compared with controls (2.8±1.3 μg/mL; P<0.001). For the 7 dogs that had samples collected on all 3 days, the mean CRP concentrations decreased significantly (P=0.043) over the 5 days of measurement. Of the 16 dogs with AP, 14 were discharged from the hospital and 2 were euthanized. Conclusions: Serum CRP concentrations were elevated in this group of 16 dogs with spontaneously occurring AP. In the 7 dogs that had measurements on all 3 days, the mean CRP concentration decreased from the day of diagnosis to the measurement made 5 days later.  相似文献   
10.
湖南猪致病性大肠杆菌的分离及药物敏感性监测   总被引:7,自引:0,他引:7  
从湖南47个规模化猪场发生典型仔猪黄、白痢猪只的63份腹泻病猪分离出63株大肠杆菌,其中12株作致病力试验均有致病性,对25种抗菌药物药敏试验,大肠杆菌对胺卡那霉素和头孢唑啉敏感,敏感菌株分别占98.41%和92.06%;多种抗生素产生耐药性,且为多重耐药。  相似文献   
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