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   113篇
  免费   11篇
  国内免费   1篇
林业   4篇
基础科学   1篇
  11篇
综合类   3篇
水产渔业   22篇
畜牧兽医   71篇
园艺   2篇
植物保护   11篇
  2021年   3篇
  2019年   1篇
  2018年   2篇
  2017年   4篇
  2016年   4篇
  2015年   8篇
  2014年   6篇
  2013年   12篇
  2012年   10篇
  2011年   9篇
  2010年   5篇
  2009年   10篇
  2008年   7篇
  2007年   4篇
  2006年   6篇
  2005年   7篇
  2004年   3篇
  2003年   7篇
  2002年   8篇
  2001年   4篇
  2000年   1篇
  1998年   1篇
  1995年   1篇
  1992年   2篇
排序方式: 共有125条查询结果,搜索用时 31 毫秒
1.
Saddleback-like syndrome is one of the most frequently observed malformations in hatchery-reared red spotted grouper Epinephelus akaara. Saddleback-like syndrome is characterized by a V-shaped dorsal-profile depression behind the head region accompanied by deformities or misalignments of the first to fourth neural spines on the vertebral column and the first to fourth pterygiophores of the dorsal fin. Abnormal swim bladder inflation in several finfish species leads to malformations, particularly of the vertebral column. The present study examined the influence of swim bladder inflation on saddleback-like syndrome in hatchery-reared red spotted grouper. The incidence of saddleback-like syndrome increased as swim bladder inflation rate increased. Additionally, the incidence of saddleback-like syndrome among juveniles with inflated swim bladders was significantly higher than that among juveniles with uninflated swim bladders. The larval swim bladder is located just below the first to fifth vertebrae and the first to fifth dorsal spines, where saddleback-like syndrome occurs. Our results suggest that an inflated swim bladder increases the risk of saddleback-like syndrome in hatchery-reared red spotted grouper.  相似文献   
2.
Trehalose, a nonreducing disaccharide consisting of d-glucose with α,α-1,1 linkage, was evaluated as a functional material to improve the gut environment in preweaned calves. In experiment 1, 173 calves were divided into two groups; the trehalose group was fed trehalose at 30 g/animal/d with milk replacer during the suckling period, and the control group was fed nonsupplemented milk replacer. Medication frequency was lower in the trehalose group (P < 0.05). In experiment 2, calves (n = 20) were divided into two groups (control group [n = 10] and trehalose group [n = 10]) based on their body weight and reared under the same feeding regimens as in experiment 1. Fresh feces were collected from individual animals at the beginning of the trial (average age 11 d), 3 wk after trehalose feeding (experimental day 22), and 1 d before weaning, and the fecal score was recorded daily. Fecal samples were analyzed for fermentation parameters and microbiota. The fecal score was significantly lower in the trehalose group than in the control group in the early stage (at an age of 14 to 18 d; P < 0.05) of the suckling period. Calves fed trehalose tended to have a higher proportion of fecal butyrate on day 22 than calves in the control group (P = 0.08). Population sizes of Clostridium spp. were significantly lower (P = 0.036), whereas those of Dialister spp. and Eubacterium spp. tended to be higher in the feces of calves in the trehalose group on day 22 (P = 0.060 and P = 0.083). These observations indicate that trehalose feeding modulated the gut environment and partially contributed to the reduction in medication frequency observed in experiment 1.  相似文献   
3.
To clarify the effect of renal dysfunction on pharmacokinetics of the prokinetic agent metoclopramide (MCP), we administered intravenously 0.4 mg/kg MCP to healthy calves and calves subjected to right kidney vessel ligation (ligation) without or with a subsequent left nephrectomy (ligation plus removal). Plasma MCP concentration, glomerular filtration rate (GFR) and plasma prolactin level were measured by liquid chromatography-tandem mass spectrometry, simplified equation using iodixanol and enzyme-linked immunosorbent assay, respectively. Only in calves with ligation plus removal, plasma MCP concentrations were increased significantly 6, 8 and 12 hr after injection, showing that a negative correlation was observed between the plasma MCP concentrations and GFR value. A tendency to increase in plasma PRL concentration was noted also in these calves. In conclusions, plasma MCP concentrations depend on the GFR mode in calves, and its critical GFR value was estimated.  相似文献   
4.
Hippocampal atrophy, which is a component of hippocampal sclerosis and recognized commonly in human intractable epilepsy, is controversial in canine epilepsy. We examined the hippocampal volume in 58 epileptic dogs and 35 control dogs using magnetic resonance (MR) images, and calculated the relative hippocampal volume asymmetry of the right and left hippocampus. Subjectively, there were visible MR imaging abnormalities in seven of the 58 epileptic dogs (12%). The hippocampel volume asymmetric ratio of epileptic dogs (5.84±4.47%) was significantly greater than that of control dogs (1.62±0.88%). Using a cutoff threshold asymmetric ratio of 6% that is indicated in human epilepsy, 28 epileptic dogs (48%) were characterized as having unilateral hippocampus atrophy. The hippocampal volume asymmetry ratio cannot be used to detect bilateral atrophy. In conclusion, although less frequent than that observed in human epilepsy patients, hippocampal atrophy may occur in canine epilepsy.  相似文献   
5.
A sensory survey was carried out using 4 different types of whole goat milk among middle‐class females to investigate consumer acceptability of goat milk and whether there is an opportunity to expand the sale of goat milk products in Japan. Four different types of whole milk powder (domestic concentrate‐fed, domestic pasture‐fed, USA commercially canned, and New Zealand commercially canned) were used. Fresh cow milk was served as a control. Thirty‐one housewives evaluated the 5 liquid milk samples for smell, taste and overall characteristics on a scale of 1 (low) to 3 (high). Chi‐square analyses were carried out to detect significant differences between the milk types in each category. The goat milk from the USA was the most preferred goat milk with respect to smell and overall evaluation. Domestic pasture‐fed milk received the lowest grade in the evaluation for its ‘grassy and goaty’ smell. This result shows us that pasture intake affects the taste and smell of powdered milk which gives the lowest evaluation by the participants. If Japanese goat milk producers want to be successful in the domestic goat milk market and compete against goat milk products from other countries, they should improve production methods and flavor of their products.  相似文献   
6.
Our previous study detected a single nucleotide polymorphism (SNP), g.1471620G > T , in the 5' flanking region of the endothelial differentiation sphingolipid G-protein-coupled receptor 1 ( EDG1 ) gene, which has been considered as a positional functional candidate for the gene responsible for marbling, and showed association of the g.1471620G > T SNP with marbling in Japanese Black beef cattle. In the present study, we investigated the allele frequency distribution of the g.1471620G > T SNP among the 5 cattle breeds, Japanese Black, Japanese Brown, Japanese Short Horn, Holstein, and Brown Swiss breeds. The T allele at the g.1471620G > T SNP associated with high marbling was found at high frequency in Japanese Black breed that has been subjected to a strong selection for high marbling, while the allele was absent or at very low frequencies in the other breeds that have not been strongly selected for high marbling. Based on this finding, we hypothesized that the pressure of the strong selection for high marbling in Japanese Black breed has increased the frequency of the T allele at the g.1471620G > T SNP in the EDG1 .  相似文献   
7.
The effect of feeding rotifers enriched with taurine on the growth performance and survival of larval amberjack Seriola dumerili was investigated. Rotifers were enriched with a commercial taurine supplement at four levels (0, 200, 400, and 800 mg/l). The larvae were fed the enriched rotifers in triplicate from 3 days post-hatch for 7 days under static conditions. The average taurine contents of the rotifers were 1.5, 2.7, 4.2, and 7.2 mg/g dry matter, respectively. The growth of the fish fed rotifers enriched with the taurine supplement at 800 mg/l was significantly (P < 0.05) improved compared with that of the fish fed the rotifers without taurine enrichment. The survival rate improved proportionally up to a taurine supplement level of 400 mg/l, but no significant differences in survival were observed among treatments. The fraction of the larvae with inflated swim bladders did not vary significantly between treatments. Taurine content in the whole fish body increased with the taurine level in the rotifers. These results suggest that taurine enrichment of rotifers is an effective method of enhancing the growth of amberjack larvae.  相似文献   
8.
The effect of docosahexaenoic acid (DHA) on the growth performance, survival and swim bladder inflation of larval Seriola dumerili during the rotifer feeding period was investigated in two feeding experiments. Amberjack larvae at 3 day post hatching were fed rotifers enriched with (1) freshwater C hlorella (Chlo), (2) a mixture (2:1, v/v) of Chlo and DHA‐enriched C hlorella (DHA‐Chlo), (3) DHA‐Chlo and (4) DHA‐Chlo and commercial DHA emulsion, in triplicate for 7 days. The average DHA contents of the rotifers were 0.0, 0.4, 1.0 and 1.9 mg g?1 DM respectively. The survival rate was improved by the enrichment of rotifers with DHA‐Chlo alone, and DHA‐Chlo and emulsion. Growth and swim bladder inflation of fish fed rotifers enriched with DHA‐Chlo were significantly (< 0.05) improved, however, with increased levels of DHA further improvement was not found. DHA content in the larval whole body proportionally increased with the DHA level in the rotifers. These results suggest that DHA enrichment of rotifers is effective to improve the growth, survival rate and swim bladder inflation of amberjack larvae. The DHA requirement of amberjack larvae is estimated to be 1.5 mg g?1 on a dry matter basis of rotifers.  相似文献   
9.
AIM: To study the expression and roles of muscarinic cholinergic receptor 3 (M3R) in human small cell lung cancer (SCLC) cells. METHODS: Human SCLC cell lines SBC3 and H82 were cultured in vitro. RT-PCR and Western blotting were used to investigate the expression of M3R. MTT assay and Boyden chamber assay were carried out to determine the roles of cholinergic receptor agonist acetylcholine iodide (ACh) and M3R antagonist 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) in the proliferation and migration of SBC3 cells. RESULTS: M3R was expressed in SBC3 and H82 cells. The relative protein expression of M3R normalized with β-actin in SBC3 was 2.65-fold higher than that in H82. ACh stimulated SBC3 cell proliferation in a dose-dependent manner. Treatment with ACh at concentrations of 10-4 and 10-3 mol/L significantly stimulated SBC3 cell growth at 48 h and 72 h (P<0.01). SBC3 cell proliferation induced by ACh was inhibited by 4-DAMP in a dose-dependent manner. Pretreatment of the cells with 10-5 mol/L 4-DAMP suppressed the effect of ACh at 48 h (P<0.05). Pretreatment with 4-DAMP at concentrations of 10-6, 10-7 (P<0.05) and 10-5 mol/L (P<0.01) inhibited the effect of ACh at 72 h. Treatment with 10-5 or 10-6 mol/L 4-DAMP alone inhibited the cell proliferation at 48 h (P<0.01) and the inhibitory effect of 4-DAMP at concentration of 10-5 mol/L was stronger than that of 4-DAMP at concentration of 10-6 mol/L at 72 h. ACh increased the cell migration towards fibronectin (Fn) in a dose-dependent manner and ACh at concentration of 10-4 mol/L enhanced the cell migration by about 3 folds. The cell migration stimulated by 10-4 mol/L ACh was almost completely blocked by pretreatment with 4-DAMP at concentration of 10-6 or 10-5 mol/L (P<0.01). CONCLUSION: M3R is expressed in human SCLC cells. The M3R antagonist inhibits SBC3 cell proliferation and migration.  相似文献   
10.
This study investigated the effect of different light intensities on feeding, growth and survival of early stage leopard coral grouper Plectropomus leopardus larvae. Four different light intensities (0, 500, 1000 and 3000 lx) were used and larvae were kept under constant light conditions from 0 day after hatching (DAH) to 5 DAH. The larvae were fed a small S-type of Thai strain rotifers at a density of 20 individuals/mL from 2 DAH. The number of rotifers in larval digestive organ and total length of larvae were examined at 3 h intervals between 04:00 and 22:00 h on 3 DAH, and thereafter at 6 h intervals until the end of the experiment (5 DAH). Four experimental trials of the larval rearing were repeated using by 60 kL mass-scale rearing tanks. The results indicate that coral grouper larvae are visual feeders and their food intake increases with increasing light intensity. Food intake of larvae reared at 3000 lx was significantly higher than those reared at 0–1000 lx on 3 DAH despite being the first-feeding day (< 0.01). On 4 DAH, total length of larvae reared at 3000 lx was significantly larger than those reared at the lower light intensities (0, 500 and 1000 lx), and thereafter light intensity significantly influenced larval feeding and growth until the end of the experiment. Survival on 5 DAH did not show a significant difference between light intensities, but survival rate at 3000 lx and 1000 lx had a tendency to be higher than those reared at the lower light intensities (0 and 500 lx). In contrast, larvae reared at 0 lx exhibited stagnant and/or negative growth. These results indicate that light intensity is significantly the factor affecting larval feeding, growth, and survival in coral grouper larvae under the rearing conditions.  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