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21.
人工养殖西伯利亚鲟精子超低温冷冻保存研究   总被引:7,自引:6,他引:7  
刘鹏  庄平  章龙珍  王斌  闫文罡 《海洋渔业》2007,29(2):120-127
研究了人工养殖西伯利亚鲟精子的生物学特征及超低温冷冻保存方法。西伯利亚鲟的产精量为113.67±39.86 ml,精子密度为(6.49±3.10)×108/ml,精子活力为(85.4±9.5)%,精子寿命为353±23 s。精子密度与精子快速运动时间、精子寿命之间均存在线性相关,用方程分别表示为:y=1.0384x+1.5089(R2=0.7325);y=2.9069x+74.289(R2=0.6967)。结果表明精子密度可作为一项精子质量评价的标准。通过比较西伯利亚鲟精子在不同稀释液、不同抗冻剂和抗冻剂浓度、降温速率、解冻温度下的保存效果,结果表明:配方2作为稀释液,18%甲醇作为抗冻剂,二步法超低温(-196℃)冷冻保存精子,40℃水浴解冻取得最好的冻后活力,解冻后活力为(51.8±5.8)%。西伯利亚鲟授精的最佳精卵比为106∶1。在此精卵比下用冻精授精分别得到了(72.3±3)%的受精率和(52.9±4.1)%的孵化率,其中受精率与鲜精没有显著性差异,孵化率与鲜精有显著差异(P<0.05)。  相似文献   
22.
The effects of straws volume, cryoprotectants and thawing temperatures were evaluated on the sperm quality of cachama blanca Piaractus brachypomus (Cuvier), an important Colombian fish species. Sexually mature fish were induced to ovulation or spermiation with a carp pituitary extract. A pool of suitable sperm samples was diluted in glucose, egg yolk, dimethyl sulphoxide (DMSO‐10%), methanol (MET‐10%) or ethylene glycol (ETG‐5%) and packed in 0.5, 2.5 or 5.0 mL straws and frozen in nitrogen vapour. The thawing process was performed in a 35 or an 80 °C water bath. The fertility was evaluated after 6 h post fertilization. The highest motility percentage (33 ± 3%) was observed with sperm cryopreserved with DMSO, packed in 5 mL straws and thawed at 35 °C. The treatments with DMSO and MET packed in 0.5 and 5.0 mL straws and thawed at 35 °C showed the highest fertility (higher than 71%) and the lowest fertility was obtained with MET‐2.5 mL (9 ± 5%). In all the treatments, a significant decrease in the sperm quality was observed at 80 °C. Sperm cryopreserved with DMSO‐10% or MET‐10%, packed in 2.5 or 5.0 mL straws are suitable to achieve acceptable fertilization and to fertilize high amounts of eggs.  相似文献   
23.
环境因子对大黄鱼精子活力的影响   总被引:1,自引:1,他引:1  
通过观测精子的激活率、活动时间和寿命研究了几种环境因子的变化对养殖大黄鱼精子活力的影响。试验结果表明:精子平均密度为(1.17±0.09)×1010.ml-1,盐度对大黄鱼精子活力影响较大。当海水盐度适宜(19.61~24.87)时,精子的激活率≥90%,活动时间≥9.65 min,寿命≥13.50 min;在pH=4.0~10.0的海水中,精子都能被正常激活(≥70%),适宜的pH值为7.5~8.0;不同浓度的葡萄糖、NaCl和KCl溶液对精子活力的影响不同,不同浓度的EDTA-2Na溶液均不能激活精子;无Ca2 、Mg2 或HCO3-的人工海水对精子的激活率均高达90%,但精子的活动时间却有较大幅度的缩减。  相似文献   
24.
Three experiments were performed to develop protocols for cryopreservation of Persian sturgeon Acipenser persicus, sperm. In the first experiment, sperm from six males was individually split in three subsamples and cryopreserved using Modified Tsvetkova's extender (mT) supplemented with dimethyl sulfoxide (DMSO), methanol (MeOH), glycerol (Gly) and ethylene glycol (EG) at concentration of 5%, 10%, 15% and 20%. In the second set of experiments, the effects of six equilibration times (0, 5, 10, 20, 40 and 60 min) and dilution ratios (volume sperm: volume extender 1:0.5, 1:1, 1:2, 1:3, 1:5 and 1:10) and the additive advantage of bovine serum albumin (BSA; 0, 2.5, 5 and 10 mg mL?1) and ascorbic acid (0, 2.5, 5 and 10 U mL?1), on the post‐thaw survival of sperm (triplicate set of six fish) were evaluated. Then, sperm was diluted in 1:1 mT extender with 10 mg mL?1 BSA with selected cryoprotectants (15% MeOH and 10% DMSO) for 5 min. After a month of storage in liquid nitrogen, post‐thawed sperm motility; fertilization and hatching rate and viability of derived larvae were measured (Exp.3). Evaluation of cryoprotectants efficiency showed that MeOH 15% and DMSO 10% were suitable for cryopreservation of Persian sturgeon sperm. Gly and EG resulted in very low post‐thaw motility rates even at lowest concentration. No significant difference was observed among the four different equilibration times (0, 5, 10, 20 min) (P > 0.05) although higher equilibration times than 20 min resulted low post‐thaw motility (P < 0.05). The motility of frozen–thawed sperm did not significantly change when dilution ratio was increased from 1:0.5 to 1:3 (P > 0.05). However, higher dilution ratios (1:5 and 1:10) reduced the percentage of motile sperm. Supplementation of the cryoprotectant solution with 10 mg mL?1 BSA significantly improved post‐thaw motility (P < 0.05), but ascorbic acid did not improve post‐thaw motility (P > 0.05). The results of experiment 3 showed that the highest fertilization (30.2 ± 5.75) and hatching rates (28.2 ± 5.25) were observed when samples were frozen with 15% MeOH (P > 0.05). Our study indicates that the use of mT extender consisting of 10 mg mL?1 BSA in 15% MeOH diluted with sperm at 1:1 ratio for 5 min can be recommended cryopreservation method for Persian sturgeon sperm.  相似文献   
25.
In this study, a non‐programmable freezing technique has been developed with the strip spawned blue mussel (Mytilus galloprovincialis) sperm. The key parameters optimized including (1) cryoprotectant agents (CPAs); (2) cooling temperature; (3) thawing temperature; (4) sugar and amino acid supplementation and (5) sperm to egg ratio. The fertilization rate and/or integrity of plasma membrane and acrosome were used as sperm quality assessment indicators. The highest post‐thaw sperm fertilization rate of 95% was achieved, when sperm were cryopreservated in 8% dimethyl sulfoxide at 7.8 cm above the liquid nitrogen surface and thawed in a 60°C seawater bath. The addition of glucose, sucrose or trehalose in dimethyl sulfoxide did not, whereas 0.8% glycine did significantly improve the post‐thaw sperm fertilization rates. The fluorescent evaluation has demonstrated that the addition of glycine significantly improved the post‐thaw sperm acrosome integrity, revealing a positive role of glycine in the improvement of post‐thaw sperm quality in blue mussels.  相似文献   
26.
The plasma membrane from spermatozoa of rainbow trout was isolated by four techniques: sonication, hypotonic shock, mechanical homogenization after freeze-thawing, and nitrogen cavitation, in combination with continuous sucrose gradient centrifugation. Nitrogen cavitation (900 PSI, 20 min equilibration at 4°C) was the most effective technique.Following nitrogen cavitation, four bands were recovered in the sucrose gradient at densities 1.03, 1.05, 1.09 and 1.15 g/ml. Electron microscopy revealed membrane vesicles of various sizes in bands 1 to 3, while enzyme analysis revealed a 3.9 to 5.5-fold enrichment in 5'-nucleotidase and little contamination by lactate dehydrogenase (cytosol) and succinic dehydrogenase (mitochondria). Lipid analysis of bands 1 and 2 indicated a 6 to 7-fold enrichment in cholesterol and a cholesterol: phospholipid ratio of 0.59–0.70. Seven classes of phospholipids were present in bands 1–3 with no significant differences observed among bands. These data indicate that the vesicles (in bands 1 and 2) obtained after nitrogen cavitation are primarily plasma membranes. Membranes in band 3 appear to be slightly contaminated with nuclear membranes.Most of the plasma membrane proteins were acidic to neutral. The 2 main membrane proteins were 42 and 30 Kilodaltons.  相似文献   
27.
试验结果表明,虾夷扇贝精子的最适盐度为23.2~32,最适pH 7.0~8.5.4℃,未稀释精液样品保存5 d后,精子仍有(26±4)%的活力,而经海水稀释后的精液保存70 h后,最高活力仅为(11±1.41)%,用抗冻液稀释的精液,4℃保存5 h后,得到最高的精子活力仅为(24.7±4.16)%.添加抗冻剂后,-18℃的保存效果明显低于4℃保存的未稀释样品.用4℃保存的未稀释精液与栉孔扇贝卵子进行杂交试验,保存3 d内的精子获得的授精率与对照组差异不显著(P0.05).杂交组的幼虫可以正常发育至D形幼虫,与自交组无区别.  相似文献   
28.
The robustness of Pacific oyster, Crassostrea gigas (Thunberg), sperm cryopreservation in the context of selective breeding based on family lines was investigated. Irrespective of egg density, high fertilization success was achieved with cryopreserved sperm when sperm:egg ratios of 1000:1 to 10 000:1 were used. Variation among replicate runs on the same oyster batches was minimal, indicating that cryopreservation and larval rearing procedures were repeatable. Twenty independent single male–female crosses were made to assess the utility of cryopreserved sperm in selective breeding. The fertility of unfrozen sperm was generally a poor predictor of cryopreserved sperm fertility. Based on D‐larval yields, 17 of the 20 crosses were likely to yield adequate spat for selective breeding (>105 D‐larvae from 1 million eggs), two were marginal (5 × 104 D‐larvae) and one was inadequate (4 × 103 D‐larvae). An alternative fertilization strategy to improve D‐yield from a given number of sperm was then tested. Fertilizing 10 million eggs at a sperm:egg ratio of 200:1 increased the total D‐yield when compared with fertilizing 1 million eggs at a sperm:egg ratio of 2000:1 for the same male–female pair. We conclude that, despite wide variation in fertility, cryopreserved sperm is useful for family production.  相似文献   
29.
ABSTRACT:   Experimental insemination was performed using artificially produced low-motility sperm. A mathematical model was applied to the results of the insemination in order to clarify the relationship between sperm motility, the density of sperm and the fertilization rate of eggs. In the model, the probability of fertilization by individual spermatozoa was a function of sperm density in the insemination solution. The results showed that the probability of fertilization clearly decreased with increased sperm density, and the maximum possible fertilizing rate by increasing the sperm density was constrained by the proportion of motile sperm (% motility). The model was also applied to the results of insemination tests of cryopreserved sperm in order to evaluate the fertilizing capacity of cryopreserved sperm. It was proven that cryopreserved sperm needed a higher density to obtain the maximum fertilization rate compared with fresh sperm, and it was anticipated that the ratio of the motile inseminated cryopreserved sperm should be more than 5.0% to achieve an egg fertilization rate greater than 90%.  相似文献   
30.
用电刺激采精方法 ,对 5只雄性成年珍珠鸡进行 2 5只次试验 ,皆获得精液。与按摩采精法相比 ,电刺激采精法采集的精液量 (0 .5 5 m L )显著高于按摩法 (0 .12 m L ) ,平均每次射出的精子总数 (4.2 2亿个 )比按摩采精法 (2 .4 4亿个 )显著增加 ,但精子活率和受精率无显著差异。冷冻试验结果表明 ,精子的活率为 2 0 %~ 5 0 % ,输精结果表明 ,受精率可达 6 0 %。  相似文献   
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