排序方式: 共有39条查询结果,搜索用时 15 毫秒
21.
糖源在棉花花药培养中起着重要作用,不同糖源所起的作用不同。可溶性淀粉、蔗糖和葡萄糖有利于棉花花药愈伤组织的诱导和生长;麦芽糖对花药愈伤组织的诱导和生长促进作用不大;乳糖不利于愈伤组织的诱导。甘露醇的添加抑制了愈伤组织的诱导和生长。不同糖浓度对棉花花药愈伤组织诱导和生长的影响也不同,一般低浓度糖易诱导形成愈伤组织和愈伤组织的快速增殖。蔗糖的最佳使用浓度为30g/L。在不含糖源的培养基上棉花花药不能诱导形成愈伤组织,继代培养的愈伤组织也不易生长。培养条件和基因型也影响着糖源的使用效果。当以淀粉为糖源时,其具有胞外水解作用。 相似文献
22.
Anne KH Krogh Pernille Legind Mads Kjelgaard-Hansen Louise Bochsen Annemarie T Kristensen 《Acta veterinaria Scandinavica》2014,56(1):11
Background
Sled dogs performing endurance races have been reported to have a high incidence of gastric erosions or ulcerations and an increased risk of gastro intestinal bleeding leading to death in some cases. In addition, these dogs also become hypothyroid during training and exercise. Canine hypothyroidism has been shown to correlate with decreased von Willebrand factor antigen and potentially increased bleeding tendency. Whether increased gastro intestinal bleeding risk is exacerbated due to changes in the hemostatic balance is unknown. The aim of this study was to investigate the hemostatic balance in sled dogs before and after exercise and in addition evaluate any correlation to thyroid status. Twenty sled dogs have been assessed in untrained and trained condition and immediately after exercise. The first sample was collected in the autumn following a resting period, and subsequently the dogs were exposed to increased intensity of training. After four months the peak of physical condition was reached and a 68 km long sled pulling exercise was performed. Samples were collected before and immediately after the exercise. Evaluated parameters were: plasma thromboelastographic (TEG) R, SP, α and MA, activated partial thromboplastin time (aPTT), prothrombin time (PT), fibrinogen, von Willebrand factor (vWf), D-dimer, platelet number, thyroid hormones, hematocrit and C-reactive protein (CRP).Results
Exercise induced an overall hypercoagulable state characterized by significant decreases of TEG R and SP and an increase of α, increased concentrations of plasma vWf and decreased aPTT. In addition, a proinflammatory status was seen by a significant increase of serum CRP concentrations. Thyroid status was confirmed to be hypothyroid as training and exercise induced significant decrease of thyroxin (T4), free thyroxin (fT4) and thyroxin stimulating hormone (TSH) concentrations. Fibrinogen decreased significantly and PT increased. The training-induced changes showed correlation between T4, fT4 and aPTT and correlation between TSH and fibrinogen. Exercise-induced changes showed correlation between T4 and PT.Conclusions
Exercise was associated with a hypercoagulable state and an increase of vWf concentration in this group of sled dogs. Decreased thyroid hormone concentrations after training and exercise were confirmed, but were associated with increased and not decreased vWf in this group of sled dogs. 相似文献24.
BC Li W Li H Chen YN Zhang ZT Zhang XY Wang B Gao TC Dou KH Wang 《Reproduction in domestic animals》2013,48(3):368-372
This study was conducted to explore the influencing factors of ova in vitro fertilization (IVF) and transfer of the fertilized ova into the oviduct of recipient hens. The efficiency of fertilization was compared using three aspects: (i) the different time of ova collection and transfer, (ii) egg‐laying period of recipient hen; and (iii) semen volume. The following results are observed: 72%, 40% and 0% of ova were found in ovarian sac in 30~40 min, 50~60 min and more than 90 min post‐oviposition, respectively; 20%, 18%, 14% and 5.8% of ova were fertilized with 0.1, 0.2, 0.5 and 1.0 ml semen, respectively; and 33% and 100% of healthy chickens were hatched from fertile ova with 0.1 and 0.5 ml of semen, respectively. All oocytes obtained from ovary and mid‐oviduct were unfertilized. Embryos were transferred into recipient hens 30 min ± 10 min post‐oviposition, and 70% of shelled eggs were produced. There were no eggs produced in the other transfer times. This demonstrated that live chicken can be obtained by IVF of ova collected shortly after oviposition. It was important that the ovum was transferred into the oviduct infundibulum of recipient hens immediately or shortly after oviposition. 相似文献
25.
The thyroid glands of two series of ninety-nine unselected dogs from consecutive autopsies in London and in Munich were examined histologically. The prevalence of goitre and of neoplasia was distinctly higher in dogs in the Munich series.
Résumé. On a examiné de façon histologiyue les glandes thyroïdes de deux séries de quatrevingt-dix-neufs chiens d'après des autopsies consécutives à Londres et à Munich. La prédominance de goîtres et de néoplasie était nettement plus élevée chez les chien de la série de Munich
Zusammenfassung. Die Schilddrüsen von zwei Serien von 99 Hunden Wurden von darauf-folgenden Autopsien in London und München histologisch untersucht. Das Vorkommenwon Kropf und Neoplasia war entschieden höher in den Hunden der Munchener Serie. 相似文献
Résumé. On a examiné de façon histologiyue les glandes thyroïdes de deux séries de quatrevingt-dix-neufs chiens d'après des autopsies consécutives à Londres et à Munich. La prédominance de goîtres et de néoplasie était nettement plus élevée chez les chien de la série de Munich
Zusammenfassung. Die Schilddrüsen von zwei Serien von 99 Hunden Wurden von darauf-folgenden Autopsien in London und München histologisch untersucht. Das Vorkommenwon Kropf und Neoplasia war entschieden höher in den Hunden der Munchener Serie. 相似文献
26.
The effect of dietary protein supply on carcass composition, size of organs, muscle properties and meat quality of pigs 总被引:1,自引:0,他引:1
This study investigated the effect of dietary protein supply on growth performance, carcass composition and size of organs in pigs slaughtered at the age of 165 ± 2 d. In addition, we analysed muscle fibre properties and glycolytic potential of light muscles longissimus lumborum (LD), semimembranosus (SM), and gluteus superficialis (GS), and dark muscles infraspinatus (IS) and masseter (M) of 20 gilts and 20 barrows. Of these pigs, 16 were Finnish Landrace, 16 were Finnish Yorkshire, and 8 were crosses of these breeds. The pigs were fed low-or high-protein diets formulated to contain 6.0 and 9.5 g of apparent ileal digestible lysine/feed unit (1 fu = 9.3 MJ NE), respectively. The pigs were fed according to a restricted weight-based feeding scale (13–30 MJ NE/d). Lean meat, fat, bones, and skin of the carcasses as well as organs were dissected and weighed. The pH value was measured 45 min post mortem from LD, and 24 h post mortem from LD, SM and GS. Drip loss, lightness (L) and redness (a) were measured from LD, SM and GS. Pigs with a low-protein supply showed a lower growth rate (P < 0.01), carcass weight (P < 0.01), and carcass lean meat content (P < 0.01), but higher carcass fat content (P < 0.01) and smaller kidneys (P < 0.01) than did pigs with a high-protein supply. In LD, the differences in cross-sectional areas in all muscle fibre types (P < 0.05) between the feeding groups were significant; in GS we found significant differences in cross-sectional areas of type IIA and type IIB (P < 0.05), while in SM we found no differences in muscle fibre cross-sectional areas between the feeding groups (P > 0.05). We found no such differences in the dark muscles studied. We also took into account the effect of both the breed and sex on the studied properties. The low-protein diet increased glycolytic potential in porcine LD and SM, and decreased the pH value measured 45 min post mortem from LD. The dietary protein supply affected no other meat quality traits studied. A more rapid drop in pH in LD resulted in a lighter and less red meat with higher drip loss. 相似文献
27.
Ghafouri Seyed Ali GhalyanchiLangeroudi Arash Maghsoudloo Hossein KH Farahani Reza Abdollahi Hamed Tehrani Farshad Fallah Mohammad Hossein 《Tropical animal health and production》2017,49(5):1089-1093
Tropical Animal Health and Production - In 2010, H5N8 highly pathogenic avian influenza (HPAI) viruses of the A/Goose/Guangdong/1/1996 lineage dramatically affected poultry and wild birds in Asia,... 相似文献
28.
Partanen R Raula J Seppänen R Buchert J Kauppinen E Forssell P 《Journal of agricultural and food chemistry》2008,56(14):5717-5722
Flaxseed oil was emulsified in whey protein isolate (WPI) and spray-dried. Powder characteristics and oxidative stability of oil at relative humidities (RH) from RH approximately 0% to RH 91% at 37 degrees C were analyzed. Oil droplets retained their forms in drying and reconstitution, but the original droplet size of the emulsion was not restored when the powder was dispersed in water. The particles seemed to be covered by a protein-rich surface layer as analyzed by electron spectroscopy for chemical analysis (ESCA). Oxidation of flaxseed oil dispersed in the WPI matrix was retarded from that of bulk oil but followed the same pattern as bulk oil with respect to humidity. A high rate of oxidation was found for both low and high humidity conditions. The lowest rate of oxidation as followed by peroxide values was found at RH 75%, a condition that is likely to diverge significantly from the monolayer moisture value. A weak baseline transition observed for the WPI matrix in a differential scanning calorimetry (DSC) thermogram suggested a glassy state of the matrix at all storage conditions. This was not consistent with the observed caking of the powder at RH 91%. Scanning electron microscopy (SEM) images revealed a considerable structural change in the WPI matrix in these conditions, which was suggested to be linked with a higher rate of oxygen transport. Possible mechanisms for oxygen transport in the whey protein matrix under variable RHs are discussed. 相似文献
29.
通过调查得到启示,就如何加快农产品加工业发展提出和论证了以下问题:加快农产品加工业发展需要全面的和深层次的转变观念;发展农产品加工业,要选准产品,主攻创名牌和保护名牌;农产品加工业要按照农业产业化经营模式发展;改制是公有制农产品加工企业必须解决的重大课题;转变政府职能和实行必要的宏观调控是农产品加工业适应市场需要发展所必须的条件。 相似文献
30.
对马兰[Kalimerisindica(L.)Sch-Bip]主要生物学特性进行了观察,并比较了5种不同生长环境的生长状况。结果表明:在土壤疏松、有机质丰富、肥力较强的栽培地上生长状况最好,产量最高;而在土壤紧实荫蔽条件下,生长最差,产量最低。这为马兰的人工驯化栽培提供了科学的依据。 相似文献