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181.
182.
4种渗透性抗冻剂对暗色唇鱼精子冷冻保存的影响 总被引:2,自引:0,他引:2
4℃冷冻保存条件下,以冷冻精子活力、寿命和细胞膜完整率为指标,检测二甲亚砜(DMSO)、甘油(Glycerol)、乙二醇(EG)和甲醇(MeOH)4种渗透性抗冻剂对暗色唇鱼(Semilabeo obscurus)鲜精以及对精子冷冻保存效果的影响.结果显示,4种渗透性抗冻剂对鲜精活力呈负作用,MeOH< EG< DMSO< Glycerol;抗冻剂对鲜精寿命呈负作用,MeOH< EG< DMSO和Glycerol;抗冻剂对鲜精细胞膜完整率呈负作用,MeOH< EG< DMSO< Glycerol.在鲜精活力为(36.17±4.06)%,寿命为(47.5±3.1)s,细胞膜完整率为(86.22 ±5.29)%时,经过短期冷冻保存,5% MeOH和5% EG解冻后暗色唇鱼精子活力最高,分别为(18.33±1.70)%和(17.83±2.67)%,与鲜精活力差异显著(P<0.05);5% MeOH和5% EG解冻后精子寿命最长,分别为(44.3±3.6)s和(42.8±5.5)s,5%MeOH解冻后精子寿命与鲜精寿命差异不显著(P>0.05);5% MeOH解冻后精子细胞膜完整率最高,为(85.67±1.11)%,与鲜精细胞膜完整率无显著差异(P>0.05).研究表明,DMSO和Glycerol并不适合作为暗色唇鱼精子冷冻的抗冻剂,MeOH和EG具有相似的保护作用,是暗色唇鱼精子冷冻保存潜在的渗透性抗冻剂. 相似文献
183.
两种奶牛性别控制胚胎生产方法的比较 总被引:1,自引:0,他引:1
试验分别应用PCR法和XY精子分离法生产性别控制奶牛胚胎,并通过移植观察准确率。结果显示,PCR法准确率为89%,XY精子分离法准确率为100%。试验表明,应用XY精子分离法进行性控胚胎生产,技术难度较小,成本较低,效果良好,生产中具有较大推广应用价值。 相似文献
184.
利用微核、精子畸变和Ames试验检测了转Bt基因水稻稻米对小鼠骨髓嗜多染红细胞(polychromatic erythrocytes,PCE)微核率(micronucleus frequency,MN%)和小鼠精子畸形发生率(sperm malformation rate)及组氨酸营养缺陷型鼠伤寒沙门氏菌株回变菌落数的影响。结果表明,在本实验条件下,Bt水稻稻米对小鼠体细胞和性细胞均无诱变活性,且无剂量效应;该受试物对TA97a、TA98、TA100和TA102菌株无论在有无代谢活化系统存在的条件下,各剂量组回变菌落数均处于正常水平。 相似文献
185.
[目的]研究季节、品种两大因素对成年公猪精液量及精子活力的影响效应。[方法]对21头长白猪和26头大白猪在一年内不同季节的精液量和精子活力进行观察和测定,并对这些精液品质进行统计学分析。[结果]季节对成年公猪精液量的影响达到显著水平(P〈0.05),但2个品种对精液量的影响没有显著差异(P〉O.05),其中长白猪的精液量在春季最多,秋、冬、夏依次减少,而大白猪的精液量在秋季最多,夏、春、冬三季则依次减少;季节和品种对成年公猪精子活力的影响均不显著(P〉O.05),但是长白猪和大白猪的精子活力均在春季最高,而夏季最低,此外一年四季长白猪的精子活力明显高于大白猪。[结论]结果为提高猪场的繁殖效率和生产水平奠定基础。 相似文献
186.
187.
通过SDS-PAGE电泳,从提取液的倍数、提取时间、Triton X-100的浓度、SDS的有无等4个方面对提取条件进行优化,确定栉孔扇贝精子膜蛋白的最佳提取条件是:将精液150g离心去除精原细胞,0·1mol/L PBS缓冲液清洗两次,0·1mol/L Tris-HCl缓冲液清洗两次,3000g离心10min(4℃)得精子悬液;然后向精子悬液中加入3倍体积含1%Triton X-100和0.1%SDS的膜蛋白提取液中冰浴振摇1·5h;4℃,50000g离心15min,收集上清精子膜蛋白溶液。SDS-PAGE电泳后,考马斯亮蓝R-250染色检测出22种膜蛋白,分子量在23~156kDa之间,PAS染色检测出糖蛋白有13种,苏丹黑B染色检测出脂蛋白有12种,其中既为糖蛋白又为脂蛋白的有8种。此研究结果可为以后进一步分离纯化栉孔扇贝的精子膜蛋白,研究其在精子发生和受精过程中的功能及作用提供基础资料。 相似文献
188.
This study aimed to assess the effects of sodium caseinate and cholesterol to extenders used for stallion semen cooling. Two ejaculates from 19 stallions were extended to 50 million/mL in four different extenders and cooled-stored for 24 hours at 5°C. The extender 1 (E1) consisted of a commercially available skim milk–based extender. The extender 2 (E2) consisted of E1 basic formula with the milk component being replaced by sodium caseinate (20 g/L). The extender 3 (E3) consisted of E1 basic formula added to cholesterol (1.5 mg/120 million sperm). The extender 4 (E4) consisted of a combination of the E2 added to cholesterol. At 24 hours after cooling, sperm motility parameters, plasma membrane stability (PMS), and mitochondrial membrane potential were assessed. In addition, cooled semen (1 billion sperm at 5°C/24 hours) from one “bad cooler” and one “good cooler” stallions, split into four extenders was used to inseminate 30 light breed mares (30 estrous cycles/extender). Milk-based extenders (E1 and E2) had superior sperm kinetics than E3 and E4 (P < .05). Plasma membrane stabilization was significantly higher (P < .05) in E4 than E1, whereas E2 and E3 presented intermediate values (P > .05). The mitochondrial potential intensity was lower (P < .05) in E2 and E4 groups compared with E1 and E3. The good cooler stallion had high fertility (∼80%) in all extenders. However, for bad cooler stallion, E1 40% (8/20) and E2 45% (9/20) had poor fertility (P < .05) compared with E4 85% (17/20), whereas E3 55% (11/20) had intermediate value (P > .05). In conclusion, the association of sodium caseinate and cholesterol improved fertility of bad cooler stallion semen cooled for 24 hours. 相似文献
189.
Sperm vitrification as an alternative approach to conventional cryopreservation (equilibrium freezing) allows quick and low-cost sample preservation and is suitable for small-bodied aquatic species with miniscule testis, fieldwork at remote locations, and small-scale freezing for research purposes. The goal of this present study was to develop operational prototypes of 3-dimensional (3-D) printed vitrification devices with innovative components that can provide comprehensive functionalities for practical repository development for aquatic species. The design featured an elongated loop to suspend a thin film of sperm sample in cryoprotectant, a retractable sleeve to protect the vitrified samples and allow permanent labeling, a handle to facilitate processing and storage, and a shaft with annular grooves to guide positioning of the protective retractable sleeve. To span a wide range of sample capacities and configurations, a total of 39 different configurations (3 loop lengths ×13 loop heights) were fabricated by 3-D printing with the thermoplastics polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS). A total of 86 devices were fabricated with ABS filament with a print failure rate of 9%, and 97 devices were fabricated with PLA filament with a failure rate of 20 %. Major types of printing failures included disconnected loops, insufficient build surface adhesion, stringing, and inconsistent extrusion. The sample volume capacity ranged from 1 to 47 μL and had linear relationships to the loop lengths and layer numbers. Vitrified samples were observed in 10-mm and 15-mm loops fabricated with PLA and ABS but not in 20-mm loops. This study demonstrated the feasibility of development of standardized low-cost ($0.05 material cost) devices fabricated by 3-D printing with practical functions including vitrification, volume control, labeling, protection, and storage within conventional systems. These prototypes can be further developed, standardized, and used to assist development of germplasm repositories to protect the genetic resources of aquatic species by user groups such as breeders, hatcheries, aquariums, and researchers. 相似文献
190.