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为研究CD8~+ T细胞的功能异常机制,对功能异常状态CD8~+ T细胞和3种正常CD8~+ T细胞亚型[中央记忆CD8~+ T细胞(HCM)、效应记忆CD8~+ T细胞(HEM)和na?ve CD8~+ T细胞(HW)]的ATAC-seq(Assay for transposase accessible chromatin with high-throughput sequencing)数据进行基因调控网络比较,结果表明,3种正常CD8~+ T细胞特异表达的基因参与维持相应T细胞正常功能的信号通路,功能异常CD8~+ T细胞特异的基因参与癌症相关通路。转录因子调控网络比较分析发现功能异常CD8~+ T细胞GMEB2转录因子表达关闭。细胞表面受体调控网络比较分析发现功能异常CD8~+ T细胞CD7和P4HB受体的表达关闭。采用基因调控网络的数据进行比较分析,发现CD8~+ T细胞功能异常机制可能与GMEB2转录因子、CD7和P4HB受体表达关闭有关,这为抗病育种寻找特定基因提供新思路。 相似文献
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Phillips T Ferraz I Bell S Clegg PD Carter SD Mobasheri A 《Veterinary journal (London, England : 1997)》2005,169(2):216-222
Glucose serves as the major energy substrate for articular chondrocytes and as the main precursor for the synthesis of extracellular matrix glycosaminoglycans in cartilage. Chondrocytes have been shown to express several glucose transporter (GLUT) isoforms including GLUT1 and GLUT3. The aim of this investigation was to determine the effects of endocrine and cytokine factors on the capacity of equine articular chondrocytes for transporting 2-deoxy-d-[2,6-3H] glucose and on the expression levels of GLUT1 and GLUT3. Chondrocytes maintained in monolayer culture were stimulated for 24 h with TNF-alpha (100 ng mL(-1)), IL-1beta (100 ng mL(-1)), IGF-I (20 ng mL(-1)), TGF-beta (20 ng mL(-1)) and insulin (12.5 microg mL(-1)) before measuring uptake of non-metabolizable 2-deoxyglucose in the presence and absence of the glucose transport inhibitor cytochalasin B. Polyclonal antibodies to GLUT1 and GLUT were used to compare GLUT1 and GLUT3 expression in stimulated and un-stimulated alginate encapsulated chondrocytes by Western blotting. Results indicated that 2-deoxyglucose uptake was inhibited by up to 95% in the presence of cytochalasin B suggesting that glucose uptake into equine chondrocytes is GLUT-mediated. Insulin had no effect on glucose uptake, but treatment with IGF-I, TGF-beta, IL-1beta and TNF-alpha resulted in a significant increase (>65%) in 2-deoxyglucose uptake compared to control values. GLUT1 was found to be increased in chondrocytes stimulated with all the growth factors and cytokines but GLUT 3 was only upregulated by IGF-I. The data presented support a critical role for glucose in the responses of equine articular chondrocytes to pro-inflammatory cytokines and anabolic endocrine factors. 相似文献
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几种生态因子对红砂和霸王种子萌发与幼苗生长的影响 总被引:20,自引:4,他引:20
自然条件下进行了土壤温度、水分、播深及覆沙地境对红砂和霸王种子萌发与幼苗生长的效应研究,结果显示,模拟阵雨期(人工洒水)覆沙和未覆沙试验小区白天播种层土壤温度均较高,尤其中午(14:00)覆沙小区1和4 cm播种层土壤温度平均值分别高达43.2和37.3℃,未覆沙小区分别高达38.0和33.6℃.高温引发种子次生休眠是该期红砂和霸王种子不能萌发的主要原因.而且播种层土壤含水量日内下降十分明显,其中覆沙和未覆沙小区1 cm土层平均土壤含水量下降至0.11%和2.62%,也会引发种子产生次生休眠,成为红砂和霸王种子不能萌发的另一原因.自然连续降水期2种试验小区播种层平均土壤温度适宜,播种层土壤含水量高而稳定,满足了红砂和霸王种子萌发的适宜温度和较高水势的条件.因此,在干旱荒漠区进行荒漠草地的人工辅助建植,需要依靠连续性降水过程.自然条件下霸王发芽率最高的播深处理在覆沙小区为2 cm、未覆沙小区为1 cm;在2种试验小区内霸王幼苗生物量最大的播深处理均为2和3 cm.覆沙较未覆沙地境有利于霸王种子萌发和幼苗的生长.播种当年霸王地上生物量为红砂的75~117倍. 相似文献
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本文对古尔班通古特沙漠及其南部不同距离绿洲的温度、气压、风向风速及净辐射进行了比较分析。结果表明,沙漠地表面温度和气温升降速度比绿洲观测点要快、变化幅度大;由于各观测点空气相对湿度和温度升降度不同,使得各观测点的气压升降幅度也不同,白天气压的变化曲线呈单蜂型;各观测点在12:00到18:00期间主导风向主要是南风,还有东南或西南风,在20:00时风速几乎为0;早上和晚上沙漠的净辐射高于绿洲,白天近地面净辐射绿洲大于沙漠;对绿洲气象要素时空效应特征分析,为棉花等绿洲优势作物的播种期、物候期、作物生育及生理生态特性具有一定的指导意义。 相似文献
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Comparison of External and Internal Pelvic Measurements of Belgian Blue Cattle from Sample Herds in Belgium and the United Kingdom 总被引:1,自引:0,他引:1
RD Murray TA Cartwright DY Downham MA Murray & A de Kruif 《Reproduction in domestic animals》2002,37(1):1-7
Measurements describing pelvic conformation of pedigree Belgian Blue cows were obtained from a sample of nine herds in Flanders, Belgium, comprising 111 adult breeding cows, and from 11 herds in the United Kingdom comprising 108 similar cows. All herds in the Belgian sample (111 cows) managed parturition by elective caesarian section as did seven herds (56 cows) in the UK sample; the remainder of UK herds (52 cows) allowed cows the opportunity to calve naturally per vagina before resorting to caesarian section. The data described the external and internal measurements, and pelvic area characteristic of this breed, irrespective of the different selection pressures applied over a number of years to this breed through variation in farm management and market forces present in either country. From these data, generalized linear models were constructed to predict pelvic area; they correctly identified cows with either small or large pelvic areas. There were no significant differences in pelvic conformation between cattle bred either in Belgium or the UK, although those cows bred in herds where natural calving was allowed to take place had significantly larger internal pelvic height (p < 0.05) and area (p < 0.05) than other Belgian Blue cows. The correlation coefficients between internal pelvic height and width and external pelvic measurements were significant (p < 0.001). These results might facilitate the selection of breeding cows with larger pelvic area so that a higher proportion of cows can calve naturally than currently occurs. However, selection for other traits such as relatively low birth weight combined with higher weaning weight should be carried out at the same time. 相似文献
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