首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   15篇
  免费   0篇
林业   1篇
农学   1篇
  5篇
综合类   1篇
水产渔业   2篇
畜牧兽医   3篇
园艺   2篇
  2021年   1篇
  2020年   1篇
  2018年   3篇
  2015年   1篇
  2013年   4篇
  2011年   2篇
  2010年   1篇
  1998年   1篇
  1980年   1篇
排序方式: 共有15条查询结果,搜索用时 46 毫秒
1.
  1. The apparent (AIAAD) and standardised ileal amino acid digestibility (SIAAD) of wheat distillers dried grains with solubles (wheat-DDGS) was determined for broilers and turkeys at 28 d using two experiments.

  2. A total of 84 male Ross 308 broiler chicks (Experiment 1) or 84 male BUT 10 turkey poults (Experiment 2) were offered a nutrient-adequate diet from d 1 to 23. On d 23, birds in each experiment were allocated to 4 treatments consisting of a nitrogen-free diet (NFD) (with or without protease) and an assay diet containing wheat-DDGS as the only source of amino acids (with or without protease) in a randomised complete block design.

  3. In Experiments 1 and 2, the coefficient of AIAAD or SIAAD of Lys and Asp were low irrespective of protease. In Experiment 1, the coefficient of AIAAD ranged from 0.35 (Ala) to 0.75 (Pro) without protease, whereas the range was 0.42 (Thr) to 0.82 (Pro) with protease. Protease improved the coefficient of AIAAD for Arg and Pro and tended to improve the coefficient of AIAAD for Met. Without protease, the coefficient of SIAAD ranged from 0.51 (Ala) to 0.84 (Pro), whereas the range was from 0.65 (Ala) to 0.93 (Pro) with protease. Protease improved the coefficient of SIAAD of Arg, Leu, Phe, Met, Val and Pro.

  4. In Experiment 2, the coefficient of AIAAD was lower than 0.50 for all amino acids except for Glu (0.70) and Pro (0.81) without protease. On the other hand, the coefficient of SIAAD ranged from 0.41 (Thr) to 0.89 (Pro) without protease, whereas the range was from 0.56 (Arg) to 0.88 (Pro) with protease supplementation. With the exception of Cys and Pro, protease improved the coefficient of AIAAD and SIAAD of all other amino acids by 0.05–0.19.

  5. It was concluded that the AIAAD and SIAAD of wheat-DDGS are variable and are generally greater in broilers compared to turkeys at 28 d of age. Protease improved the ileal digestibility of a large number of amino acids in wheat-DDGS for broilers and turkeys.

  相似文献   
2.
Two forms of rhodanese were purified from the liver of Clarias gariepinus Burchell, designated catfish rhodanese I (cRHD I) and rhodanese II (cRHD II), by ion-exchange chromatography on a CM-Sepharose CL-6B column and gel filtration through a Sephadex G-75 column. The apparent molecular weight obtained for cRHD I and cRHD II was 34,500 ± 707 and 36,800 ± 283 Da, respectively. The subunit molecular weight determined by sodium dodecyl sulphate–polyacrylamide gel electrophoresis was 33,200 ± 283 and 35,100 ± 141 Da for cRHD I and cRHD II, respectively. Atomic absorption spectrophotometric analysis revealed that cRHD II contained a high level of iron (Fe), which presumably was responsible for the brownish colour of the preparation. In contrast, no Fe was identified in cRHD I, and its preparation was colourless. Further characterization of cRHD II gave true Michaelis–Menten constant (K m) values of 25.40 ± 1.70 and 18.60 ± 1.68 mM for KCN and Na2S2O3, respectively, an optimum pH of 6.5 and an optimum temperature of 40°C. The Arrhenius plot of the effects of temperature on the reaction rate consisted of two linear segments with a break occurring at 40°C. The apparent activation energy values from these slopes were 7.3 and 72.9 kcal/mol. Inhibition studies on the cRHD II enzyme showed that the activity of the enzyme was not affected by Mn2+, Co2+, Sn2+, Ni2+ and NH4 +, but Zn2+ inhibited the enzyme considerably.  相似文献   
3.
The blood pressure lowering effect of a pea protein hydrolysate (PPH) that contained <3 kDa peptides, isolated by membrane ultrafiltration from the thermolysin digest of pea protein isolate (PPI), was examined using different rat models of hypertension as well as hypertensive human subjects. The PPH showed weak in vitro activities against renin and angiotensin converting enzyme (ACE) with inhibitory activities of 17 and 19%, respectively, at 1 mg/mL test concentration. Oral administration of the PPH to spontaneously hypertensive rats (SHR) at doses of 100 and 200 mg/kg body weight led to a lowering of hourly systolic blood pressure (SBP), with a maximum reduction of 19 mmHg at 4 h. In contrast, orally administered unhydrolyzed PPI had no blood pressure reducing effect in SHR, suggesting that thermolysin hydrolysis may have been responsible for releasing bioactive peptides from the native protein. Oral administration of the PPH to the Han:SPRD-cy rat (a model of chronic kidney disease) over an 8-week period led to 29 and 25 mmHg reductions in SBP and diastolic blood pressure, respectively. The PPH-fed rats had lower plasma levels of angiotensin II, the major vasopressor involved in development of hypertension, but there was no effect on plasma activity or renal mRNA levels of ACE. However, renal expression of renin mRNA levels was reduced by approximately 50% in the PPH-fed rats, suggesting that reduced renin may be responsible for the reduced levels of angiotensin II. In a 3-week randomized double blind placebo-controlled crossover human intervention trial (7 volunteers), significant (p<0.05) reductions (over placebo) in SBP of 5 and 6 mmHg were obtained in the second and third weeks, respectively, for the PPH group. Therefore, thermolysin derived bioactive peptides from PPH reduced blood pressure in hypertensive rats and human subjects, likely via effects on the renal angiotensin system.  相似文献   
4.
This study reports on the influence of seed position within the fruit and shoot development on the production of jackfruit in vitro. Seeds were extracted from the different sections in the fruit and shoot tips excised from the resultant seedlings. The tips were cultured in vitro on media supplemented with 6-benzylaminopurine (BAP) or thidiazuron (TDZ). The seeds from the middle and basal sections of the fruit were larger and produced larger seedlings than those from the top. Seeds from the basal position took 10 days to germinate and produced seedlings 11 cm tall with four or five leaves. Partially covered and fully open shoots from 6–8 week-old seedlings performed best. The highest frequency of shoot induction (100%) and multiple shoot production (7.31 ± 1.2) with a mean length of 3.6 ± 0.13 cm was observed on Murashige and Skoog (MS) media supplemented with 3.0 mg/L BAP. Driver and Kuniyuki (DKW), and MS media were equally effective in shoot multiplication. More than 80% of the rooted plants survived culture, indicating that this technology could be used to conserve wild germplasm.  相似文献   
5.
Appropriate planting patterns ensure sustained soil fertility and higher productivity for farmers. This study assessed the intercropping crop combinations and information sources of kola farmers in Osun State, Nigeria. Sixty respondents were selected using multistage and purposive random sampling techniques. Data were collected with a structured questionnaire. The arable crops commonly intercropped with kola were plantain/banana, yam, cassava, and maize. Tree crops combined with kola included cocoa, citrus, and oil palm. Co-farmers/friends and radio served as popular sources of information for farmers. Farm size was significantly related to respondents’ information sources on kola intercropping. The authors recommend that the Cocoa Research Institute of Nigeria's extension personnel make greater use of information sources most frequently used by respondents in order to ensure adequate cropping systems.  相似文献   
6.
The distribution of Zn, Cu, Cd, Cr, Pb, Ni, and Mn in the soil, and related soil properties was studied in Abeokuta, southwestern Nigeria. Their soil pollution source was hypothesized to be automobile traffic. Consequently, their variations were assessed as a function of traffic density, distance from road and traffic, and soil depth. Soil samples were collected from the areas of high, medium, and low traffic densities at 0, 50, 100, 150, and 200 m from roadside; at depths 0–20, 20–40, 40–60, 60–80, and 80–100 cm. The potential effects of these metals on environment and agricultural activities were also assessed. Results indicated that the major sources for the metals’ contamination are emissions from vehicles. High and medium traffic volume impacted more metals of the soils. Zinc, Cu, Cd, and Cr were concentrated at depths 0–40 cm, Pb, Ni, and Mn were concentrated at 0–20 cm and appeared bound to soil organic matter (SOM). Significantly lower concentrations of metals are found at distances of 100 m and beyond. Concentrations of these metals are generally low compared with standards and their uptake by crops is not probable. However, their continuous accumulation might be a threat in the future.  相似文献   
7.
8.
Journal of Crop Science and Biotechnology - Crops are constantly faced with the challenges of different abiotic stresses on the field. Development of sustainable approach for stress amelioration on...  相似文献   
9.
Veterinary Research Communications - Infections with divergent strains of astroviruses appear to be endemic in commercial poultry. In order to investigate enteric viruses associated with hatchery...  相似文献   
10.
The aim of this study was to determine the presence of trichinellosis in backyard-farmed pigs and the risk factors associated with the infection in Zaria, Kaduna State. Serum samples were collected from 120 pigs selected at random from 50 small backyard farms, and the presence of Trichinella spp. antibodies was determined using a commercially available enzyme-linked immunosorbent assay (ELISA) kit. Data on farm management practices from the farms were obtained through the use of a structured questionnaire. The overall seroprevalence of Trichinella spp.-specific antibodies was 40 % (48/120) by ELISA. All the extensive farms sampled had at least one Trichinella-positive animal. The age and sex of the animals were not significantly (p?>?0.05) associated with the infection; however, the management systems, presence of rodents, rodent control, and access to dead pigs showed significant (p?<?0.05) association with Trichinella spp.-infected pigs on the farm. In conclusion, there was a high prevalence of antibodies to trichinellosis in backyard raised pigs in Zaria, and intensive pig farming with the adoption of proper biosecurity measures is advocated to prevent the transmission and spread of trichinellosis.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号