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721.
为鉴定胸膜肺炎放线杆菌(Actinobacillus pleuropneumoniae,APP)ApxIA毒素蛋白N端疏水区和C端Ca^2+结合区的免疫原性,参照apxIA基因序列(D16582)设计4条引物,用于扩增APP血清10型参考菌株(D13039)基因组DNA中长约3.2kb的apxIA基因及其N端(1.4kb)和C端(1.8kb)基因片段,经克隆测序后分别插入原核表达载体pET-32a中进行表达,表达的融合蛋白大小分别约为125Ku、65Ku和80Ku。表达产物免疫小鼠后的攻毒保护试验结果显示,ApxIA表达蛋白对APP血清10型(D13039)攻毒可提供完全保护,而对APP血清1型(4074)攻毒仅能提供部分保护,与提纯的Apx1毒素蛋白免疫保护效果相当;ApxIA-N端表达蛋白免疫保护活性显著高于ApxIA-C端表达蛋白,提示ApxIA蛋白免疫活性位点多位于N端,在Apx1毒素蛋白的保护性抗原活性中发挥更重要作用。 相似文献
722.
纤维素复合酶对羔羊消化道组织结构的影响 总被引:1,自引:0,他引:1
为了探明纤维素复合酶提高羔羊饲料消化率的消化道组织学基础,选择刚出生且体重相近的波尔山羊公羔30只(20日龄开始自由采食优质苜蓿干草, 80日龄断奶)分为对照组和试验组(添加0.2%酶制剂),分别在2、3和4月龄每组各选体重相近的3只羔羊屠宰.结果表明,瘤胃乳头长度、宽度和单位面积瘤胃乳头表面积随月龄增加而增加,而单位面积乳头数随着月龄的增加而减少(P < 0.01).酶制剂提高3、4月龄羔羊瘤胃乳头长度(P < 0.01)、宽度(P > 0.05)和单位面积瘤胃乳头表面积(P < 0.01),减少单位面积乳头数(P < 0.01).显著提高3月龄十二指肠肠绒毛的长度(P < 0.05).在3、4月龄,酶制剂有增加小肠隐窝深度和黏膜厚度的趋势,但未达到显著水平(P > 0.05). 相似文献
723.
724.
96头始重(24.14±1.12)kg的杜长大三元杂交猪,随机分为4组。第1组为对照组,饲喂基础日粮(含氟量37.39mg/kg),第2、3、4组分别饲喂含氟(以NaF形式添加)量为100、150、200mg/kg的日粮,研究日粮中不同氟水平对猪生长性能和血清某些生化指标的影响,并探讨了氟在肝、肾和肌肉中的沉积,饲料氟和粪氟、血清氟、尿氟之间的相关关系。结果表明,第3、4组猪增重与对照组相比分别降低8.86%(P<0.05)和9.81%(P<0.05),料重比分别升高7.36%(P<0.05)和8.07%(P<0.05)。第4组血清钙、镁、白蛋白含量和碱性磷酸酶的活力与对照组相比分别降低了17.33%(P<0.01)、29.91%(P<0.01)、10.75%(P<0.05)和33.71%(P<0.01)。第3、4组肝、肾和肌肉氟含量与对照组相比显著增加(P<0.05)。各试验组粪氟、血清氟、尿氟含量随饲料中氟含量的增加而升高,且各组间差异极显著(P<0.001),饲料氟与粪氟、血清氟、尿氟含量相关系数分别为0.943(P<0.01)、0.911(P<0.01)和0.959(P<0.01)。 相似文献
725.
应用RT-PCR技术从经植物血凝素(PHA)刺激诱导的奶牛脾脏淋巴细胞总RNA中扩增出牛-γ干扰素基因(bovine interferon-γ,BovIFN-γ)cDNA,并克隆到pGEM-T easy载体中,经过限制性酶切分析和测序证实,所克隆到的基因编码区序列与已报道的序列完全一致.将含信号肽的BoIFN-γ基因整个编码区cDNA亚克隆到杆状病毒转座载体pFastBac Ⅰ中,构建了转移载体pFastBac 1-BoIFN-γ,转座到宿主菌DH10 Bac中,在含庆大霉素、四环素、卡那霉素、IPTG和X-gal的KGTIX LB平板上筛选白色菌落,提取DNA获得重组穿梭载体Bacmid-BoIFN-γ质粒,与脂质体共转染Sf9细胞,产生有感染力的重组杆状病毒reBac-BoIFN-γ.重组病毒经过传代扩增感染Sf9细胞,通过IFA试验、Western-blot和抗病毒活性测定证实,BoIFN-γ基因在感染的昆虫细胞和上清中得到了表达,上清中活性可达2.651×105U/mL.表达条件优化结果表明,不同MOI对rBoIFN-γ的表达产量影响不大,上清中干扰素活性在感染后5 d达到高峰. 相似文献
726.
将健康围产期奶牛30头随机分为3组.预产前28d按奶牛营养需要分别饲喂100%、120%、80%能量日粮,产后各组奶牛均饲喂标准的产奶日粮,至产后56d结束,观测干奶期不同能量摄入水平对围产期健康奶牛血中神经肽Y和生长激素浓度的影响。结果表明,干奶期低能量日粮饲喂,奶牛血中神经肽和生长激素浓度均高于其他2组,从产前14d至产后28d组间差异显著(P〈0.01;P〈0.05),提示低能量饲料饲喂干奶期奶牛,产后能量负平衡得到缓解。 相似文献
727.
728.
CHENG He-xiang ZHOU Lian XU Ke-wei JIA Guo-liang WANG Hai-chang GUO Wen-yi ZHANG Rong-qing 《园艺学报》2006,22(10):1917-1921
AIM: To investigate the effects of constant magnetic field on apoptosis, secretion and expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in human umbilical vein endothelial cells (HUVEC), and their adhesion rates with THP-1 monocytes induced by angiotensin Ⅱ (AngⅡ).METHODS: The third passage of cultured HUVEC was used.There were six groups: control group, Ang Ⅱ (10-6 mol/L) group, Ang Ⅱ with 1, 5, 10 or 20 gausses of constant magnetic field group.Samples were collected 24 h after incubation with or without magnetic field.Apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and propidinm iodide staining with flow cytometry.Secretion and expression of ICAM-1 and VCAM-1 were detected by ELISA and immunocytochemistry, respectively.Adhesion rate between HUVEC and THP-1 was measured by counting method.RESULTS: Ang Ⅱ at concentration of 10-6mol/L induced apoptosis in HUVECs (P<0.05 vs control), whereas in 1, 5, 10 and 20 gausses group, apoptosis of HUVECs was significantly lower than that in Ang Ⅱ group (P<0.05).Ang Ⅱ at concentration of 10-6 mol/L significantly increased secretion and expression of ICAM-1 and VCAM-1 (P<0.05 vs control), whereas secretion and expression of ICAM-1 and VCAM-1 in 1, 5, 10 and 20 gausses group significantly decreased, compared with Ang Ⅱ group (P<0.05).The adhesion rates between HUVEC and THP-1 significantly increased 24 h after incubation of HUVEC with Ang Ⅱ (P<0.05 vs control), in contrast, the adhesion rates between HUVEC and THP-1 in 1, 5, 10 and 20 gausses group significantly decreased, compaed with Ang Ⅱ group (P<0.05).CONCLUSIONS: One gauss to 20 gausses of constant magnetic field antagonizes the effects of Ang Ⅱ on HUVEC, decreases apoptosis and expression of ICAM-1 and VCAM-1 in HUVEC, and also decreases the adhesion rates between HUVEC and monocytes induced by Ang Ⅱ. 相似文献
729.
AIM: To observe the function and morphological change of human umbilical vein endothelial cells (HUVECs) treated with lipopolysaccharide (LPS) and composite salviae dropping pills (DSP). METHODS: HUVECs were cultured and incubated within 10 mg/L LPS for 12 hours. Different final concentrations of composite salviae dropping pills (1 g/L, 0.5 g/L, 0.25 g/L, 0.1 g/L) were added before and after LPS treatment. Cell viability, NO, NOS, ET-1 and intracellular calcium were measured. The cells were observed under inverted microscope, inverted phase contrast microscope, laser confocal scanning microscopy and transmission electron microscope. RESULTS: When given after LPS treatment, different final concentrations of composite salviae dropping pills played a protective role (P<0.05), and the concentration of 0.5 g/L was the most effective (P<0.01). When given before LPS treatment, 0.5 g/L and 0.25 g/L of composite salviae dropping pills protected the human vascular endothelial cells (P<0.05), but 1 g/L and 0.1 g/L didn't play a protective role (P>0.05). The HUVECs injured by LPS underwent apparent morphological change after treatment with composite salviae dropping pills. CONCLUSION: Composite salviae dropping pills have an evident protective effect on human umbilical vein endothelial cells exposed to LPS. 相似文献
730.
LI Ya-qing ZHANG Zhen-xiang XU Yong-jian CHEN Shi-xin NI Wang YANG Zhao MA Dan 《园艺学报》2006,22(5):948-952
AIM: To study the effect of cigarette smoke medium (CSM) on the gene expression and activity of gelatinases from alveolar macrophages (AMs) in the rat, and then to explore their role in the pathogenesis of chronic obstructive pulmonary disease (COPD). METHODS: AMs were obtained from BALF of the rats that had smoked for 12 weeks. CSM was produced following the method of Wirtz and colleagues, and the cultured AMs were respectively stimulated for 24 h by 0%, 1%, 3%, 5%, 10%, 15% CSM. The mRNA levels of MMP-9 and MMP-2 were detected by semi-quantitative RT-PCR, and the enzyme activity was measured by Zymography. RESULTS: When the concentration of CSM was below 5%, the expression and activity of MMP-9 and MMP-2 signficantly increased with the concentration of CSM in a dose-depended manner (P<0.05). While the concentration of CSM exceeded 5%, the expression and activity of MMP-9 and MMP-2 correspondingly decreased with the increase in CSM concentrations (P<0.05), which possibly were related with the cytotoxicity of CSM. CONCLUSION: The expression and activity of MMP-9 and MMP-2 are induced by CSM. The gelatinases induced by smoking from AM may play an important role in the pathogenesis of COPD. 相似文献