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81.
The objective of this study was to estimate the effects of breed, sex, and halothane (HAL‐1843TM) genotype on fatty acid composition of triacylglycerols (TAG) and phospholipids (PL) extracted from porcine longissimus muscle (LM). Purebred Yorkshire (n = 131), Duroc (n = 136), Hampshire (n = 49), Spotted (n = 35), Chester White (n = 74), Poland China (n = 51), Berkshire (n = 169) and Landrace (n = 82) pigs (n = 727; 427 barrows and 300 gilts) from the 1994 and 2001 National Barrow Show Sire Progeny Tests were used. For statistical analyses, a mixed model was used that included fixed effects of breed, sex, HAL‐1843TM genotype, year, slaughter date within each year, interaction of breed × sex and random effects of sire and dam within breed. Breeds and sex were significantly associated with the percentages of the majority fatty acids in TAG. Duroc pigs had greater total saturated fatty acids (SFA) and lower total monounsaturated fatty acids (MUFA) (p < 0.05) contents than did pigs of all other breeds except Berkshire (p > 0.05). The concentration of total polyunsaturated fatty acids (PUFA) was the greatest in Hampshire pigs (p < 0.05). The content of total SFA was greater (p < 0.01), whereas the concentrations of total MUFA and PUFA were lower (p < 0.01) in barrows than those in gilts. The contents of major SFA in PL did not differ significantly among pigs from different breeds and sex groups. However, breed and sex significantly affected the concentrations of major MUFA and PUFA in PL and strong negative correlation between the total contents of MUFA and PUFA in PL was observed in the current study. Chester White pigs had greater total MUFA and lower total PUFA contents (p < 0.05) in PL than did pigs of all other breeds except Spotted (p > 0.05). In contrast to breed and sex effects, the concentrations of fatty acids in PL were more affected by HAL‐1843TM genotype than those in TAG. The content of C16:0, a major SFA in PL, differed significantly in pigs with different HAL‐1843TM genotypes. In conclusion, these results suggest that breed and sex are important sources of the variations for fatty acid composition of TAG and PL in LM.  相似文献   
82.
小麦三个品质性状微量检测方法的应用与评价   总被引:1,自引:0,他引:1  
张晓  李曼  江伟  朱冬梅  高德荣 《麦类作物学报》2014,34(12):1651-1655
为探讨小麦育种中简单、可行和高效的品质选择指标,给小麦品质改良提供借鉴,对蛋白质含量、籽粒硬度和SDS沉淀值在本单位育种中的应用效果进行分析,结果表明籽粒硬度在不同基因型间的变异系数最大,在不同栽培条件和不同年份表现稳定,是有效、可靠的选择指标;SDS沉淀值与蛋白质含量、籽粒硬度均呈极显著正相关,在基因型间的变异较大,可作为一个能反映总体品质水平的选择指标;蛋白质含量在基因型间变异系数小,受环境影响大,用于早代选择效果不理想。品质育种中可根据籽粒硬度和SDS沉淀值进行初步选择。  相似文献   
83.
From a review of the literature, we conclude that the main mechanism by which grazing livestock affect biodiversity in pastures is the creation and maintenance of sward structural heterogeneity, particularly as a result of dietary choice. We identify lack of understanding of the currencies used by animals in their foraging decisions and the spatial scale of these decisions as major constraints to better management. We conclude that there are important differences between domestic grazing animal species in their impact on grazed communities and that these can be related to differences in dental and digestive anatomy, but also, and probably more importantly, to differences in body size. Differences between breeds within species appear to be relatively minor and again largely related to body size. We conclude that there is an urgent need to understand the genetic basis of these differences and also to separate true breed effects from effects of rearing environment. We also review the economic implications of using different animal types and conclude that there is a need for more research integrating these aspects with biodiversity outcomes.  相似文献   
84.
85.

Background

Despite the increasing popularity of Icelandic horses, published reference intervals (RIs) in this breed are rare. Due to their isolation and their small gene pool, alterations in some variables are likely and some possible breed-specific peculiarities have been described. The purpose of the present study was the establishment of comprehensive RIs in Icelandic horses according to recently published guidelines.In a prospective observational study, blood samples were collected from the jugular vein of 142 Icelandic horses into EDTA and serum tubes. Reference intervals were established for haematologic and biochemical analytes on the Advia 2120i™ and the Dimension ExL™ by established methods. RIs were defined as central 95 % intervals bounded by the 2.5th and 97.5th percentiles with their 90 % confidence intervals, calculated according to recently published ASVCP guidelines. An inhouse-developed quality control system using observed total allowable error was used for the surveillance of the internal quality control preceding the measurements.

Results

The RIs were as follows: haematocrit: 0.29–0.39, RBC: 5.79–8.63 T/l, haemoglobin: 102.0–142.3 g/l, MCV: 42–51 fl, platelets: 146–263 G/l, WBC: 4.13–8.57 G/l, segs: 1.98–4.73 G/l, lymphocytes: 1.25–3.49 G/l, monocytes: 0.06–0.31 G/l, eosinophils: 0.04–0.50 G/l, glucose: 4.0–5.7 mmol/l, urea: 3.2–6.4 mmol/l, creatinine: 79.6–141.4 μmol/l, total protein: 54.4–72.9 g/l, albumin: 27.7–36.8 g/l, total bilirubin: 8.1–21.1 μmol/l, triglycerides: 0.03–0.44 mmol/l, cholesterol: 1.75–2.90 mmol/l, ALP: 1.35–3.55 μkat/l, AST: 4.52–8.80 μkat/l, GLDH: 0.0–0.18 μkat/l, GGT: 0.11–0.39 μkat/l, CK: 2.53–6.52 μkat/l, LDH: 3.32–7.95 μkat/l, iron: 16.4–39.9 μmol/l, calcium: 2.69–3.19 mmol/l, phosphate: 0.5–1.3 mmol/l, magnesium: 0.6–0.9 mmol/l, sodium: 134–141 mmol/l, potassium: 3.6–4.7 mmol/l, chloride: 100–105 mmol/l.

Conclusions

Reference intervals of several haematologic and biochemical analytes differed from the transferred historical reference intervals applied to equine samples in the authors’ laboratory. These might be of clinical importance in some analytes such as creatine kinase.

Electronic supplementary material

The online version of this article (doi:10.1186/s13028-015-0120-4) contains supplementary material, which is available to authorized users.  相似文献   
86.
选择45周龄体重接近的健康本地鸡441只,随机分为7组,在山西省太谷县生态养鸡场进行2(补饲量)×3(密度)两因子放养试验,研究林下种植苜蓿不同放养密度与补饲量对蛋鸡生产性能和蛋黄胆固醇含量的影响。补饲量设自由采食量50%、70%两个处理,密度为每667m2 100只、250只、400只3个处理,以笼养全程自由采食为对照,每组3个重复,每重复3个小区用于轮牧,小区面积为62 m2;预试期7 d,正试期70 d。结果表明:补饲量和放养密度互作对平均产蛋率影响极显著(P0.01),对蛋重和料蛋比影响不显著(P0.05)。笼养+自由采食组(CK)与补饲量70%、100只·667m-2组蛋重、平均产蛋率及料蛋比差异不显著(P0.05),但产蛋率显著高于其他各组(P0.05),蛋重显著高于补饲量50%、100只·667m-2组(P0.05),料蛋比显著低于补饲量50%组(P0.05)。补饲量和放养密度互作对蛋黄重、蛋黄胆固醇含量和全蛋胆固醇含量影响不显著(P0.05);放养密度对全蛋胆固醇含量影响极显著(P0.01)。笼养+自由采食组蛋黄重极显著高于补饲量50%、100只·667m-2组(P0.01),蛋黄胆固醇含量和全蛋胆固醇含量显著高于100只·667m-2组(P0.05)。补饲量70%下,100只·667m-2放养密度对牧草的破坏性小于其他放养密度。结合产蛋性能、蛋黄胆固醇含量以及草地保护,以70%补饲量+100只·667m-2组养殖模式较好,效果较佳。  相似文献   
87.
优质细毛羊是近几年在进口羊基础上经选育扩繁形成的国内最新的品种群。为了有效地开发这一品种,了解该品种的生产性能水平及其在同类品种中所处的地位是十分必要的。本试验通过与国内最具代表性的中国美利奴羊采用同期同龄同环境饲养的对比方法,进行了两品种间对比试验,得出初步结果,中国美利奴羊在生产发育、毛量、毛长和羊毛生长等性状较为突出,体现了强毛型品种特征,而优质细毛羊在羊毛品质性状方面较为突出,尤其是细度在66~80支纱范围,比中国美利奴羊高出一个档次,具有明显的细型美利奴品种特征。  相似文献   
88.
四种紫花苜蓿的核型分析   总被引:1,自引:0,他引:1  
为研究我国引进和本国育成的适于我国北方不同地区种植的四个紫花苜蓿(Medicago sativa)品种遗传基质的结构特征,对它们进行了细胞染色体的核型分析。试验利用植物压片法对四个品种:阿尔冈金(加拿大)、WL-323ML(美国)、WL-232HQ(美国)、中苜1号(中国农科院畜牧所用中外品种混合选育而成)进行了核型分析,结果表明:四个品种的染色体数目均相同(2n=32),统属于大染色体,但在核型组成上存在有一定的差异。四个品种中多数染色体为中部着丝点,核型多为对称型。但阿尔冈金、WL-232HQ及中苜1号同为2A型,它们相邻间染色体长度变化不大,进化程度相当,而WL-323ML为2C核型。第1,2对及第15,16对相邻间染色体长度变化大,余者变化小。它比前三个品种表现出更为进化的特点。阿尔冈金没有随体,WL-232HQ有1对随体,WL-323ML、中苜1号各有2对随体。  相似文献   
89.
山羊的起源驯化和品种形成   总被引:4,自引:0,他引:4  
回顾了山羊野祖及其驯化传播过程的传统观点。以考古学、历史学和畜牧学研究结果为依据,提出了家养山羊多地起源的观点,并认为中国是山羊早期独立驯化地之一。认为各地方山羊品种形成是在自然选择和人工选择作用下长期适应的结果,中国北方地区山羊品种形成过程中包含了古代西域山羊的血统。  相似文献   
90.
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