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101.
6个栽培类型药用菊花超氧化物歧化酶同工酶分析   总被引:2,自引:0,他引:2  
为了揭示药用菊花6个栽培类型的遗传多样性,采用聚丙烯酰胺凝胶电泳(PAGE),对不同栽培类型药菊进行SOD同工酶分析。结果表明,6个栽培类型药菊共得到9条SOD同工酶酶谱,其中4条是各栽培类型在4个时期共有的特征酶谱;各栽培类型药菊的SOD同工酶均在8月份表达量最大,酶带总数最多,其中异种大白菊、大洋菊、小洋菊的酶带总数最多,均有8条,贡菊的酶带总数最少,仅有4条;异种大白菊、大洋菊、小洋菊间的亲缘关系最近,贡菊仅与黄金菊亲缘关系较近。6个栽培类型药菊在不同的生长发育时期SOD同工酶遗传变异丰富。8月份是采集样品分析SOD同工酶的最佳时期。利用SOD同工酶谱特征可以找出各栽培类型药菊间的差异。  相似文献   
102.
为探讨苏云金芽胞杆菌高温诱导产黑色素机制,利用含mini-Tn10转座子载体pIC333构建苏云金芽胞杆菌油松亚种4CA1,随机插入突变体库,以寻找相关调控基因。通过高温诱导筛选得到1株在42℃产黑色素减弱的菌株;克隆得到mini-Tn10中断基因的部分序列,通过测序及同源性比对分析,确定中断基因为超氧化物歧化酶基因sodA2。  相似文献   
103.
Antioxidant vitamins are commonly used as colorant, preventive, sweetener, nutritive and antioxidant materials in food industry. Thus, many studies have been conducted in recent years. We have performed the present study to understand the effects of α-lipoic acid (ALA), vitamin C and E, added into rations of Japanese quails, on chronic heat stress. This study was carried out in five groups as: control, stress, ALA, vitamin E and vitamin C groups. Heat stress is applied to all groups except the control group. Superficial pectoral muscles tissues were used for biochemical determinations. During the research, it is found that heat stress exerted undesired effects such as increasing lipid peroxidation (LPO) level indicating oxidative stress in Japanese quails. In addition, superoxide dismutase (SOD) and catalase (CAT) enzyme activities and glutathione (GSH) amounts were studied to understand the behaviour of defence mechanism. While stress increased LPO ratio, it was determined that all antioxidant added into the ration decreases LPO significantly (p < 0.05). In addition, it was determined that all of antioxidants added into ration effectively restored SOD activity and LPO ratio which heat stress affected negatively. Interestingly, vitamin C did not adjust GSH ratio in contrast to vitamin E and ALA, where vitamin E and C did not perform any positive effect on heat stress decreased CAT activity. Finally, it can be thought that antioxidant vitamins relatively ameliorated these undesired affects caused by stress factors given.  相似文献   
104.
本研究旨在探讨铜和维生素A及其互作效应对内仔鸡生长性能及抗氧化功能的影响.试验选用1日龄艾维茵肉仔鸡448只,随机分为8组,每组4个重复,每个重复14只鸡.采用4×2(铜×维生素A)完全随机设计,饲粮铜的添加量分别为0、8、150、225 mg/kg,维生素A的添加量分别为1 500、5 000 IU/kg,分为2个生长阶段,前期为1~4周龄,后期为5~7周龄.结果表明:1)高铜( 150、225mg/kg)抑制了全期肉仔鸡生长性能,提高了全期血清铜蓝蛋白(Cp)和后期血清总超氧化物歧化酶(T-SOD)活性(P<0.05).2)5 000 IU/kg维生素A组获得较好的生长性能,提高了全期血清T-SOD活性,降低了前期血清Cp活性(P<0.05).3)铜和维生素A互作效应对前期体增重、血清Cp和T-SOD活性及全期料重比有显著影响(P<0.05),且二者间存在互补作用.铜(8 mg/kg)×维生素A(5 000 IU/kg)组与铜(0 mg/kg)×维生素A(5 000 IU/kg)组对前期肉仔鸡获得良好生长性能和提高血清T-SOD活性均有促进作用,但对血清Cp活性有显著降低作用(P<0.05).由此可见,在基础饲粮铜水平为16~23mg/kg时,铜的适宜添加量为前期8 mg/kg,后期0~8 mg/kg;全期维生素A的适宜添加量为5 000 IU/kg.  相似文献   
105.
为研究抗松针褐斑病菌在湿地松子代组培苗体内的苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)、超氧化物歧化酶(SOD)的活性变化与其抗病性的关系,以抗病湿地松瓶内组培苗和温室1年生组培苗针叶为材料,测定PAL、PPO、SOD的活性。结果表明:松针褐斑病菌毒素处理后,湿地松PAL和PPO活性与抗病性成一定正相关关系,SOD活性与植株抗病性在48 168 h内表现有一定的负相关性。  相似文献   
106.
The yeast Pichia membranaefaciens has antagonistic effects against a wide range of phytopathogenic fungi that cause postharvest fruit decay. This work evaluated the effects of P. membranaefaciens on the reactive oxygen species (ROS) metabolism and disease control in harvested citrus fruit (Citrus sinensis L. Osbeck). The lesion diameter caused by Penicillium italicum and Penicillium digitatum on citrus fruit was remarkably reduced when the fruit was point-inoculated or dipped in a suspension of P. membranaefaciens at 1 × 108 CFU mL−1. The application of P. membranaefaciens on citrus fruit enhanced the activity of superoxide dismutase, ascorbate peroxidase, and glutathione reductase, as well as the levels of hydrogen peroxide, the superoxide anion and glutathione, but inhibited the decreasing ascorbic acid content. Furthermore, catalase activity was decreased by the same treatment. These results indicated that yeast treatment induced the synthesis of antioxidant enzymes which might have antagonistic effects against postharvest green and blue mold infection in citrus fruit.  相似文献   
107.
Luteoprotective mechanisms of luteinizing hormone (LH) involved in the maintenance of bovine corpus luteum (CL) function have not been completely clarified. Since antioxidant enzymes are well documented as antiapoptotic factors in the CL of many mammals, we hypothesized that the luteoprotective action of LH is mediated by stimulating the local production and action of antioxidant enzymes. To test the above hypothesis, in the present study, we examined the mechanisms involved in the luteoprotective actions of LH. Cultured bovine luteal cells obtained from the CL at the mid-luteal stage (days 8–12 of the estrous cycle) were treated with LH (10 ng/ml), onapristone (OP; a specific progesterone receptor antagonist, 100 μM) and diethyldithiocarbamate [DETC; an inhibitor of superoxide dismutase (SOD), 100 μM] for 24 h. LH in combination with or without OP significantly increased the mRNA and protein expressions of manganese SOD (Mn-SOD) and catalase (CATA) and SOD activity. While LH alone significantly increased the mRNA and protein expressions of SOD containing copper and zinc (Cu,Zn-SOD), OP in combination with or without LH significantly decreased the mRNA and protein expressions of Cu,Zn-SOD. In addition, Cu,Zn-SOD, Mn-SOD and CATA mRNA expressions were higher at the mid luteal phase than the other luteal phases. LH in combination with DETC significantly decreased LH-increased cell viability. The overall results suggest that LH increases cell viability by LH-increased antioxidant enzymes, resulting in maintenance of CL function during the luteal phase in cattle.  相似文献   
108.
板栗铁型超氧化物歧化酶基因(CmFeSOD)的克隆及原核表达   总被引:1,自引:0,他引:1  
超氧化物歧化酶(Superoxide dismutase,SOD)是逆境条件下清除细胞内活性氧的关键酶,而铁型超氧化物歧化酶(FeSOD)作为该酶系中的关键酶之一,与植物的抗病性关系密切。根据板栗(Castanea mollissima Bl)转录组数据中分析得到FeSOD基因EST序列设计PCR扩增引物,以板栗幼叶的cDNA为模板,采用RT-PCR技术克隆获得CmFeSOD基因cDNA序列,通过生物信息学方法分析该基因的cDNA序列,并推定其氨基酸序列,同时将该基因片段连接到原核表达载体pET28a中,转化大肠杆菌BL21(DE3)并进行不同条件的诱导表达。结果表明,板栗CmFeSOD基因开放阅读框(ORF)大小为705 bp,共编码234个氨基酸,推测其蛋白分子质量为26.016 5 ku,理论等电点(pI)为6.86,具有FeSOD家族的特征基序和保守结构域,GenBank登录号为KY312852。遗传进化分析表明,板栗CmFeSOD与核桃的亲缘关系最近。SDS-PAGE电泳分析表明,通过原核表达获得CmFeSOD蛋白的分子质量约为29 ku,CmFeSOD蛋白在30℃,添加0.4 mmol/L IPTG,诱导6 h表达量最高,主要以包涵体的形式存在。  相似文献   
109.
Two separate experiments, one as drought stress conditions and the other one as the normal irrigation conditions based on randomized complete block design with three replications were implemented to examine 20 triticale (Triticoseclae wittamack X) genotypes of which 19 genotypes have recently been generated by crossing different parent lines and the other one was Javaniloo, a common cultivar. Based on the results of different statistical techniques and comparing relationships among traits for normal irrigation and stress condition, enzymatic antioxidant could be used as criteria for screening tolerant genotypes of triticale. On the other hand, it is pointed out that superoxide dismutase are the most important criteria to achieve higher tolerant genotypes through indirect selection. Furthermore, hydrogen peroxide and malondialdehyde content having high relationship with rain yield are also the different possible criteria for screening triticale genotypes for water stress conditions in which genotypes with lower content of these traits could be screened.  相似文献   
110.
【目的】南洋楹属典型热带树种,抗寒性较差,严重制约其推广应用。开展南洋楹无性系抗寒性评价,对于提高其造林成效、拓广其栽培区域具有重要意义。【方法】以生长较好的9个南洋楹无性系组培苗为研究对象,通过系列低温处理,观测幼苗叶片形态变化,分析测定叶片相对电导率(REC)、脯氨酸(PRO)含量以及超氧化物歧化酶(SOD)的活性,揭示南洋楹无性系在低温胁迫下的生理响应,并进行无性系抗寒性评价。【结果】在2℃时,所有无性系均出现不同程度落叶;0℃时所有无性系均出现顶芽死亡,其抗寒性差异主要表现在0~2℃温度区间;9个无性系的REC随温度降低呈单调上升和先上升后下降再上升的2种变化趁势,属于后者的无性系抗寒性更强,0℃下S5、S7的REC最低;PRO含量随温度降低整体上呈现递增趁势,TL18、S7、S5、A8的PRO含量增幅最大,均在1倍以上;SOD活性在同一温度下无性系之间差异显著,但随温度降低无明显变化规律。应用REC进行聚类分析,将9个无性系分为3类,S7、S5、TL18抗寒性最强,A8抗寒性最差,其它6个无性系抗寒性居中。【结论】建议生产上推广S7、S5和TL18无性系。  相似文献   
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