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   41篇
  免费   1篇
林业   1篇
基础科学   1篇
  3篇
综合类   12篇
农作物   3篇
水产渔业   2篇
畜牧兽医   15篇
园艺   2篇
植物保护   3篇
  2022年   1篇
  2021年   1篇
  2020年   1篇
  2017年   1篇
  2016年   1篇
  2015年   1篇
  2014年   1篇
  2013年   1篇
  2011年   1篇
  2010年   1篇
  2009年   1篇
  2008年   3篇
  2003年   2篇
  2001年   2篇
  2000年   2篇
  1999年   2篇
  1997年   1篇
  1991年   1篇
  1990年   1篇
  1986年   2篇
  1985年   2篇
  1984年   2篇
  1917年   1篇
  1916年   1篇
  1915年   1篇
  1906年   1篇
  1902年   1篇
  1901年   1篇
  1900年   1篇
  1899年   1篇
  1893年   1篇
  1891年   1篇
  1890年   1篇
排序方式: 共有42条查询结果,搜索用时 234 毫秒
1.
2.
3.
4.
5.
6.
The changes in the plasma levels of oestrone sulphate and oestradiol-17β during the oestrous cycle, gestation and puerperium in the goat are described. The oestrone sulphate concentrations remained fairly constant (250–350 pg/ml) throughout the oestrous cycle until day 20 when a sharp increase of the oestrone sulphate plasma levels occurred in pregnant goats which became significantly different at day 38 of gestation from nonpregnant values. Oestradiol-17β plasma levels were significantly lower at days 17–20 in pregnant than in nonpregnant does. Oestrone sulphate and oestradiol-17β concentrations rose until the 12th week of gestation and then declined to about 50% of the former ranges of concentrations before rising again to high values at weeks 17–20 of gestation. Increasing plasma levels of oestrone sulphate and oestradiol-17β were determined during the last ten days preceding parturition. The concentrations of oestrone sulphate returned to basal levels by the 2nd—4th day post partum whereas oestradiol-17β values reached base values 24 hours after parturition. Both oestrogen concentrations remained constant during the puerperium until day 51 post partum .  相似文献   
7.
The water extract of guar meal ( Cyamopsis tetragonolobus) was examined for its foamability. Compared with egg white, the extract showed an extraordinary foam stability: no drainage after 3 h of standing in contrast to 65% drainage for egg white at the same protein concentration. The acid-precipitated protein from the extract was responsible for the high foamability and designated guar foaming albumin (GFA). The foaming activity of GFA was 20 times higher than that of egg white. GFA consisted of two subunits with molecular masses of 6 and 11 kDa linked to each other through disulfide bonds. The cleavage of disulfide bonds in GFA affected the foamability only slightly. GFA remarkably decreased the surface tension of water at low protein concentrations. Immunoblotting analysis demonstrated that GFA did not react to the antisera from allergic patients against plant food. These results suggest that GFA serves as an effective food additive in developing protein-stabilized foam.  相似文献   
8.
9.
Vitamin A and provitamin A carotenoids are involved in the regulation of adipose tissue metabolism and inflammation. We examined the effect of dietary supplementation using all-trans and 9-cis β-carotene-rich Dunaliella bardawil alga as the sole source of vitamin A on obesity-associated comorbidities and adipose tissue dysfunction in a diet-induced obesity mouse model. Three-week-old male mice (C57BL/6) were randomly allocated into two groups and fed a high-fat, vitamin A-deficient diet supplemented with either vitamin A (HFD) or β-carotene (BC) (HFD-BC). Vitamin A levels in the liver, WATs, and BAT of the HFD-BC group were 1.5–2.4-fold higher than of the HFD group. BC concentrations were 5–6-fold greater in BAT compared to WAT in the HFD-BC group. The eWAT mRNA levels of the Mcp-1 and Cd68 were 1.6- and 2.1-fold lower, respectively, and the plasma cholesterol and triglyceride concentrations were 30% and 28% lower in the HFD-BC group compared with the HFD group. Dietary BC can be the exclusive vitamin A source in mice fed a high-fat diet, as shown by the vitamin A concentration in the plasma and tissues. Feeding BC rather than vitamin A reduces adipose tissue macrophage recruitment markers and plasma lipid concentrations.  相似文献   
10.
The pharmacokinetics of sulphadoxine-trimethoprim was studied in 6 pre-ruminant calves using two different products. Product A, which contained 200 mg sulphadoxine and 40 mg trimethoprim per mL, was administered intravenously or subcutaneously at a dosage of 25 mg sulphadoxine and 5 mg trimethoprim.kg-1 bodyweight. Product B, containing 62.5 mg sulphadoxine and 12.5 mg trimethoprim per mL plus lidocaine (1 mg.mL-1), was given subcutaneously at the same dosage. After intravenous administration of product A the mean time of half-life of elimination phase (t1/2) for sulphadoxine was 12.9 h, steady-state volume of distribution (Vd(ss)) was 0.44 L.kg-1 and clearance was 0.024 L.kg-1.h-1. Respective values for trimethoprim were 1.9 h, 2.0 L.kg-1 and 0.9 L.kg-1.h-1. After subcutaneous administration, the bioavailability of sulphadoxine was 96% and 98% and the time to reach a maximum concentration was 6.3 and 8.0 h for products A and B, respectively. The Cmax for trimethoprim was higher for product A (0.49 microgram.mL-1) than for product B (0.32 microgram.mL-1) (p = 0.014). Slow absorption from the injection site appeared to delay the elimination of trimethoprim after subcutaneous administration when compared to that after intravenous administration: apparent elimination t1/2 for trimethoprim after intravenous administration of product A was 1.9 h compared to 3.9 h and 3.6 h after subcutaneous administration of products A and B, respectively. The difference between intravenous and subcutaneous administrations was statistically significant (p < 0.05). Also the mean residence time was significantly shorter (p < 0.05) after intravenous administration (2.4 h) than that after subcutaneous administration of product A (6.9 h) and B (7.1 h). The bioavailability of trimethoprim was lower than that of sulphadoxine: 76% and 74% for products A and B, respectively. All 6 calves showed pain after subcutaneous administration of product A and the injection sites were warm and showed soft oedematous reactions 5-8 cm in diameter. Three of the calves also showed some pain after subcutaneous administration of product B; the local reactions were less severe. A marked increase was seen in creatine kinase activity after subcutaneous administration of both products. Product A caused a more pronounced increase but the difference was not statistically significant. We suggest 30 mg.kg-1 at 24-h intervals or alternatively 15 mg.kg-1 at 12-h intervals as the minimum dosage of sulphadoxine-trimethoprim combination for pre-ruminant calves. Extravascular routes of administration should be avoided due to marked tissue irritation at the injection site.  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