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91.
已报道的膳食纤维测定方法很多,概括起来主要有洗涤剂法和酶法两大类。洗涤剂法操作简单方便,但只能得到不溶性纤维含量;酶法就可以分析出可溶性纤维与不溶性纤维。本研究欲采用酶-重量法测定苦瓜中不溶性及可溶性膳食纤维含量。酶-重量法于20世纪80年代在国外首先发展起来,现已成为AOAC认可的分析方法,在我国也得到广泛使用。  相似文献   
92.
建设河北现代果业初探   总被引:1,自引:0,他引:1  
分析河北果品业的发展现状及制约因素,叙述河北现代果业的内涵及特征,提出建设河北现代果业的思路、目标及措施。  相似文献   
93.
花尾榛鸡是国家Ⅱ级保护动物,由于非法盗猎、天敌的侵害、严寒的影响,使花尾榛鸡受到伤害,因此需要采取多种方法进行人为救助。  相似文献   
94.
A complete sequence for the RNA 3 of Prunus necrotic ringspot virus (PNRSV) is described (Genbank Accession U57046). Primers from this sequence were used to amplify both the movement protein and coat protein genes of 3 other isolates of PNRSV originating from different host species and geographic locations. Comparisons of these sequences with those of other published sequences for PNRSV and the closely related apple mosaic virus (ApMV) showed that both the movement proteins and coat proteins of isolates of PNRSV are extensively conserved irrespective of either the original host or the geographic origin. The movement protein and coat protein of ApMV and PNRSV are sufficiently conserved to suggest that these two viruses may have evolved from a common ancestor. The amino acid sequence of the two coat proteins shows areas of similarity and difference that would explain the serological continuum reported to occur among isolates of these two viruses. Nevertheless, the movement protein and coat protein of the two viruses are sufficiently different so that ApMV and PNRSV should be considered to be distinct viruses.  相似文献   
95.
鸡贫血病雏鸡ND免疫后局部免疫组织抗体生成细胞变化   总被引:1,自引:1,他引:0  
对感染鸡贫血病毒(CAV)雏鸡新城疫(ND)疫苗免疫及其强毒攻击后局部免疫组织——盲肠扁桃体和哈德尔腺的IgA、IgG和IgM抗体生成细胞数量的动态变化进行了检测。结果发现,CAV感染雏鸡ND免疫后7、14、28d及新城疫强毒(vNDV)攻击后,上述免疫组织的三种抗体生成细胞数量均不同程度地低于未感染CAV的ND免疫对照雏鸡。其中盲肠扁桃体弥散区的IgA减少最为明显。表明CAV感染雏鸡消化道和呼吸道局部免疫组织对新城疫疫苗的体液免疫应答功能降低。新城疫强毒攻击后CAV感染ND免疫雏鸡的免疫保护率也明显低于未感染CAV的免疫对照雏鸡。  相似文献   
96.
利用生理调节剂F89提高皖西白鹅的摄食量,加速动物生长。日粮中添加2mg/kgF89,连续饲喂8~35日龄皖西白鹅,日摄食量较对照组增加6.02%,增重提高9.40%,耗料比下降2.89%。对育肥期鹅的增重也有明显影响。血液代谢物分析表明:饲喂F89后,皖西白鹅血清中葡萄糖和尿酸浓度下降,β-脂蛋白浓度上升。提示F89不仅能促进鹅的摄食量,而且可以影响鹅的代谢机能,促进生长  相似文献   
97.
无人机喷雾作业边界探测识别是无人直升机喷雾的重要内容,如果喷雾最大喷幅超过目标区域,会导致药液流失,造成环境的严重污染。为此,基于无人直升机平台,选取二维激光扫描传感器、姿态传感器等传感器搭建了一套二维激光扫描探测系统。该系统利用二维激光传感器探测无人直升机距离作物冠层和田埂的高度,计算冠层和田埂距离差值,并把高度差值作为分割阈值,实现无人直升机作业边界的提取,同时进行了田间试验验证。  相似文献   
98.
以滑子蘑菌丝体为试材,利用热水浸提法提取多糖,采用体外细胞试验、琼脂凹环法,检测了滑子蘑多糖的抗肿瘤、抑菌活性,并研究了多糖的保湿特性,以期为滑子蘑多糖的开发利用提供参考依据。结果表明:与空白试验组相比,滑子蘑多糖对小鼠巨噬细胞Ana-1的促增长率为48.65%,对胃癌细胞HGC-27的增殖抑制率为58.21%,对乳腺癌细胞BT-549的增殖抑制率为76.83%,对宫颈癌细胞Hela-229的增殖抑制率为63.57%;滑子蘑多糖对革兰氏阴性菌大肠杆菌、沙门氏菌及革兰氏阳性菌金黄色葡萄球菌均有抑制作用,且随着浓度的升高,抑制性增强;在30℃、RH 45%的恒温恒湿条件下,保湿性大小顺序为壳聚糖透明质酸山梨醇滑子蘑多糖甘油,在30℃、RH 80%的恒温恒湿条件下,保湿性大小顺序为透明质酸山梨醇壳聚糖滑子蘑多糖甘油,2种条件下滑子蘑多糖的保湿率都高于甘油,说明滑子蘑多糖有较好的保湿性。  相似文献   
99.
AIM: The influence of MCMV infection on differentiation and differentiation gene expression in neural stem cells(NSCs) in vitro were investigated for studying the mechanisms of brain abnormalities caused by congenital cytomegalovirus infection.METHODS: NSCs were separated from fetal BALB/C mouse, and cultured and identified in vitro. The differentiation potency of NSCs was observed by immunofluorescence. The NSCs infected by MCMV at dosage of MOI(multiplicity of infection) equaled to 5, 1 and 0.1,respectively, were cultured in differentiation medium. The morphological changes of infected cells were observed under inverted microscope. The ratios of NSCs and its differentiated cells were detected by flow cytometry. The expressions of nestin, GFAP and NSE, markers of NSCs and its differentiated cells, were studied by immunofluorescence(MOI=1). The expression of early antigen(EA) of MCMV was detected to observe the infection process. Real-time RT-PCR method was employed to measure the expression levels of the key genes Neurog2, Myc and Ccnd1 in Wnt signal pathway of NSCs at early stage of differentiation culture.RESULTS: NSCs isolated from embryonic mouse brains proliferated to form neurospheres, strongly expressed nestin and differentiated into NF-200 positive neurons or GFAP positive astrocytes. The infected NSCs did not adhere to the wall and appeared differentiation growths, but showed swollen gradually after differentiation culture. The nestin expression in the infected cells downregulated slowly and was higher than that in control groups(P<0.05). The GFAP and NSE expressions of the infected cells were lower than those in control groups(P<0.05). The early antigen(EA) of MCMV was always detected in the cells in infected groups. The ratios of nestin positive cells in infected groups were higher than those in control groups, but the ratios of GFAP and NSE positive cells of former were lower than that of the latter from 3rd to 9th d after differentiation culture(P<0.05). The levels of Neurog2 mRNA and Myc mRNA in infected groups were markedly lower than those in normal control groups on 1st d and from 1st to 4th d after differentiation culture, respectively(P<0.05). The levels of Ccnd1 mRNA of infected groups were obviously lower than those in normal control groups from 12th h to 1st d(P<0.05). These changes in infected groups became more obvious as MCMV MOI increased.CONCLUSION: MCMV significantly inhibits differentiation of NSCs to neurons and astrocytes, and leads to the decrease in differentiated cells. MCMV inhibits or interferes with the gene expression of Neurog2, Myc and Ccnd1 in Wnt signal pathway of NSCs. The effect that MCMV inhibits the expressions of differentiation and the differentiation genes in NSCs shows dose-dependent with MCMV MOI. The inhibitory effect of MCMV on the differentiation of NSCs might be induced by interfering with the expression of differentiation gene in NSCs, which is possibly the one of primary causes of brain development disorders induced by congenital CMV infection.  相似文献   
100.
为制备大肠杆菌内毒素多克隆抗体,应用大肠杆菌内毒素作为抗原免疫5周龄家兔,辛酸-硫酸铵法和葡聚糖凝胶层析法分离提纯抗血清,十二烷基磺酸钠-聚丙烯酰胺凝胶(SDS-PAGE)电泳方法鉴定多抗纯度,紫外分光光度计测定抗体蛋白含量,ELISA法检测抗血清效价与交叉反应;大肠杆菌内毒素抗体含量和效价分别为6.95mg/ml和1:12800;成功制备出抗大肠杆菌内毒素多克隆抗体,为大肠杆菌内毒素病诊断试剂盒的研制奠定基础。  相似文献   
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