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153.
泽泻对大鼠急性肝脏损伤的保护作用 总被引:1,自引:0,他引:1
为考察泽泻提取物对DL-乙硫氨酸(DL-ethionine)致肝脏损伤的保护作用,并探讨其作用机制。采用DL-乙硫氨酸(2.0mmol/L)处理大鼠原代肝细胞24h,制备大鼠急性肝脏损伤体外模型。分别以0.0、1.0、5.0、10.0、20.0、50.0μg/mL的泽泻粗提物作用于该模型,测定各组24h和48h细胞培养基上清液中的ALT、AST活性以及细胞裂解液中的甘油三酯(TG)、直接低密度脂蛋白胆固醇(D-LDL-C)。结果表明,添加泽泻的各组细胞培养基上清液中ALT、AST活力明显降低,细胞裂解液中TG、D-LDL-C含量降低,24h比48h时效果显著。泽泻粗提物的各浓度中,以5.0μg/mL为最佳。 相似文献
154.
比较不同形态及不同粗纤维水平日粮对1~50日龄鸵鸟生产性能的影响,为鸵鸟雏鸟的全价颗粒饲粮配制提供试验论证及合理的粗纤维水平数据。选取1日龄健康的鸵鸟160只,随机分为4个处理(1个对照组,3个试验组),每处理4个重复,每重复10只雏鸟,对照组日粮形态为精料(粗纤维为5%)+苜蓿青草,3个试验组的日粮形态为全价颗粒饲料(其粗纤维水平分别为4%、5%、6%)。饲喂精料+苜蓿青草形态日粮的雏鸟体增重和饲料效率显著高于饲喂全价颗粒饲料的各处理(P0.05),并且没有雏鸟死亡;3个不同粗纤维水平的颗粒料的采食量和体增重的差异都不显著(P0.05),其中粗纤维水平为5%的颗粒饲料饲喂的效果相对较好,但该组的死亡率最高,为15.0%。以精料+苜蓿青草形态的日粮饲喂1~50日龄鸵鸟的效果好于饲喂全价颗粒饲料的效果;全价颗粒饲料粗纤维水平过低会引起鸵鸟雏鸟的粪干便秘并造成死亡,本试验表明,1~50日龄鸵鸟饲料中的粗纤维水平不宜低于6%。 相似文献
155.
Symmetrical alopecia, scaling and hepatitis in a rabbit 总被引:1,自引:1,他引:1
A 5-year-old rabbit with inappetence, symmetrical alopecia and skin lesions was examined. No mites or Malassezia were found in skin scrapings and tape impressions and dermatophyte culture was negative. Trial therapy with ivermectin did not reduce skin lesion severity, and euthanasia was performed because of anorexia after 1 month. Histopathology of the skin showed hyperkeratosis, lymphocytic exocytosis, cell-poor interface dermatitis (lymphocytic infiltration and apoptotic cells in basal layer of epidermis), absence of sebaceous glands and lymphocytic mural folliculitis comparable to sebaceous adenitis and thymoma-associated exfoliative dermatitis previously described in rabbits. The liver exhibited an interface hepatitis, comparable to autoimmune hepatitis in man. The occurrence of morphological similarities to exfoliative dermatitis and sebaceous adenitis in rabbits, in association with an autoimmune hepatitis, has not been described before. 相似文献
156.
Licht BG Lin S Luo Y Hyson LL Licht MH Harper KM Sullivan SA Fernandez SA Johnston EV 《Journal of the American Veterinary Medical Association》2007,231(10):1520-1528
OBJECTIVE: To determine clinical characteristics and mode of inheritance of seizures in a family of Standard Poodles. DESIGN: Case series. ANIMALS: 90 Standard Poodles descended from the same maternal bloodline (30 with probable idiopathic epilepsy [PIE] and 60 without any history of seizures). PROCEDURES: Researchers contacted owners to determine whether dogs had ever had any seizures and, if so, the nature of any such seizures and any potential underlying causes. Dogs were considered to have PIE if they were between 6 months and 7.5 years old at the time of seizure onset and had no evidence of any underlying cause. To determine the mode of inheritance, segregation analyses were designed to allow the family to be analyzed as a whole, as opposed to as nuclear families. Competing models of inheritance were compared statistically for their ability to explain the data. RESULTS: Of the dogs with PIE, 28 (93%) had focal onset seizures with or without secondary generalization. Median age of onset was 3.7 years; 6 dogs were > 5 years old at the onset of seizures. Segregation analyses strongly suggested that PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that in this family of Standard Poodles, PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance. Seizures often had focal, as opposed to generalized, onsets, and it was not uncommon for seizures to begin after 5 years of age. 相似文献
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Although research on dairy goat mammary gland have referred extensively to molecular mechanisms, research on lines of dairy goat mammary epithelial cells (MECs) are still rare. This paper sought to establish an immortal MEC line by stable transfection of human telomerase. MECs from a lactating (45 days post‐parturition) Xinong Saanen dairy goat were cultured purely and subsequently transfected with a plasmid carrying the sequence of human telomerase. Immortalized MECs by human telomerase (hT‐MECs) exhibited a typical cobblestone morphology and activity and expression levels of telomerase resembled that of MCF‐7 cells. hT‐MECs on passage 42 grew vigorously and ‘S’ sigmoid curves of growth were observed. Moreover, hT‐MECs maintained a normal chromosome modal number of 2n = 60, keratin 8 and epithelial membrane antigen (EMA) were evidently expressed, and beta‐casein protein was synthesized and secreted. Beta‐casein expression was enhanced by prolactin (P < 0.05). Lipid droplets were found in hT‐MECs, and messenger RNA levels of PPARG, SREBP, FASN, ACC and SCD in hT‐MECs (passage 40) were similar to MECs (passage 7). In conclusion, the obtained hT‐MEC line retained a normal morphology, growth characteristics, cytogenetics and secretory characteristics as primary MECs. Hence, it can be a representative model cell line, for molecular and functional analysis, of dairy goat MECs for an extended period of time. 相似文献