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31.
[目的]探究子宫内膜炎患牛唾液生物标志物特点,[方法]研究收集试验组子宫内膜炎患牛和对照组健康奶牛唾液,针对所选10种生物标志物使用相关试剂盒在自动生化分析仪上进行检测,并将所得数据进行对比分析。[结果]相比健康奶牛,子宫内膜炎患牛唾液生物标志物的升高项为α唾液淀粉酶、皮质醇、乳酸和尿酸,而腺苷脱氨酶、乙酰胆碱酯酶水平、pH值、钠钾比则下降明显。[结论]说明应激、炎症和氧化应激在患子宫内膜炎奶牛体内的存在,钠营养状况略受影响。  相似文献   
32.
通过对膜下滴灌棉田施加旱地龙和禾康两种土壤改良剂,研究两种不同化学改良剂对改良盐碱地的应用效果及对棉花生长与产量的影响,为盐碱地改良提供理论依据.结果表明:在滴灌棉田施用旱地龙和禾康后,土体含盐量呈下降趋势,脱盐率分别为30.3%和17.7%,而对照区脱盐率仅为10.4%;借助钠吸附比概念对土壤阳离子组成进行分析,旱地...  相似文献   
33.
芸薹素内酯和复硝酚钠对茭白生长发育和产量的影响   总被引:1,自引:0,他引:1  
陈建明 《长江蔬菜》2013,(18):53-55
通过研究芸薹素内酯和复硝酚钠两种植物生长调节剂对茭白生长发育和产量的影响。研究结果表明,喷施1.8%复硝酚钠水剂5.94mgm(有效成分含量,下同)、0.04%芸薹素内酯水剂0.07mg/L以及1.8%复硝酚钠水剂与0.04%芸薹素内酯水剂等体积混配液1.84mg/L等三种处理均能使茭白结茭时间提早4-5d,茭白的有效苗数、结茭率和产量显著提高。建议在茭白孕茭前15~30d喷施1次,隔7d后再喷1次较好。  相似文献   
34.
本研究拟通过分析丁酸钠对脂多糖(LPS)诱导的奶牛乳腺上皮细胞系(MAC-T细胞)炎性损伤的修复作用,进一步从体外角度阐述丁酸钠对奶牛乳腺健康的调控机制。在MAC-T细胞中添加不同浓度(0、1、10、100、1 000、10 000 ng/mL)的LPS,检测细胞活力,以确定LPS的适宜浓度,建立细胞氧化损伤模型;并进一步在MAC-T细胞中添加不同浓度(0、2、4、8、16、32μmol/L)的丁酸钠,检测细胞凋亡率,以确定丁酸钠的适宜浓度。最终选用1 000 ng/mL LPS和16μmol/L丁酸钠用于本试验。试验分为3组,分别为对照组、LPS处理组和LPS+丁酸钠处理组,分别对其细胞形态、氧化应激指标及凋亡蛋白mRNA表达水平进行检测。结果表明:1)对照组MAC-T细胞呈扁平的无规则形态,贴壁状态良好;而LPS处理组MAC-T细胞核固缩、破裂,并出现大面积死亡脱落现象;LPS+丁酸钠处理组MAC-T细胞边缘清楚,胞内颗粒较少,死亡脱落现象明显减少。2)与对照组相比,LPS处理组MAC-T细胞中超氧化物歧化酶(SOD)活性和总抗氧化力(T-AOC)显著降低(P<0.05),丙...  相似文献   
35.
The aim of this series of studies was to evaluate two possible feeding strategies as methods for reducing the risk of calcium oxalate (CaOx) formation in two breeds of healthy dog. The studies compared the effect of dietary moisture (Study 1) and dietary sodium (Na), (Study 2) on urine composition of labrador retrievers (LR) and miniature schnauzers (MS). A nutritionally complete dry dog food was fed to 16 dogs (eight LR, eight MS; Study 1) and 15 dogs (seven LR, eight MS; Study 2) for 24 days (Study 1), or 36 days (Study 2). The dogs were fed the diet alone (7% moisture, 0.06 g Na/100 kcal), or supplemented with deionised water to 73% moisture (Study 1), or dietary Na, to deliver 0.20 or 0.30 g Na per 100 kcal (Study 2). Urine pH, volume, specific gravity, and concentrations of 12 analytes were measured for each dog. Urinary relative supersaturations (RSS) with CaOx were calculated from these values. The effects of supplemental Na or water were established using t tests (Study 1) or analysis of variance, and multiple range tests (least significant difference) (Study 2); P<0.05 was considered significant. Increasing dietary moisture significantly increased total moisture intake (P=0.001), and reduced urine specific gravity (P=0.003), urinary oxalate concentration (P=0.04), and CaOx relative supersaturation (P=0.04) in the MS. Urinary parameters remained unchanged in the LR, indicating that feeding a high moisture diet may reduce the risk of CaOx formation in high-risk breeds. Increasing dietary Na led to production of urine with a significantly lower CaOx RSS in both breeds, indicating that sodium supplementation to dry diet formats may reduce the risk of CaOx formation. These feeding strategies should be considered when evaluating methods for preventing CaOx formation within high-risk groups.  相似文献   
36.
Colletotrichum gloeosporioides is the causal organism of anthracnose inCarica papaya L. (papaya, papaw). The effect of ammonium carbonate (3%) or sodium bicarbonate (2%) in aqueous solution or when incorporated into a wax formulation on anthracnose severity in inoculated or naturally infected fruits was examined. Both salts had significant effects, but that of ammonium carbonate was greater than that of sodium bicarbonate in controlling anthracnose. Ammonium carbonate (3%) incorporated into the wax formulation effectively reduced anthracnose incidence by 70% in naturally infected papaya and extended the storage life by maintaining the firmness, color and overall quality of the fruit in low temperature storage (13.5°C) and 95% r.h. for 21 days followed by 2 days under marketing conditions. The mode of action of ammonium carbonate on the control of anthroacnose appears to bevia complete inhibition of radial mycelial growth and conidia germination. http://www.phytoparasitica.org posting Aug. 14, 2002.  相似文献   
37.
家兔亚硒酸中毒的病理形态学研究   总被引:1,自引:0,他引:1  
给家兔分别肌肉注射不同剂量的亚硒酸钠,历时入周,复制出亚急性硒中毒的动物模型。病理形态学变化为:家兔的生长受到明显抑制,肝,肾,心,脾等组织器官损害严重如肝实质细胞变性,坏死;肾实质退行病变;心肌纤维变性,充血,肺淤血,水肿:脾萎缩,淋巴细胞坏死,肝,肾,心细胞内线粒高度肿胀,嵴减少,断裂或消失成空泡。  相似文献   
38.
39.
This study investigated effect of increasing level of dietary sodium using sodium bicarbonate or sodium chloride on growth performance, mortality, characteristics of carcass, organs and tibia, calcium and phosphorus of serum in broilers reared in a high‐altitude area (1,700 m above sea level). A total of 588 Ross 308 male broiler chicks were used in seven treatments, six replicates per treatment of 14 birds per each from 1 to 38 d of age. Seven dietary treatments consisted of a basal diet (with 0.16% sodium and 0.23% chloride), top‐dressed for six diets to give three supplementary levels of sodium (0.07%, 0.14% and 0.21%) from sodium bicarbonate (respectively by 0.26%, 0.52% and 0.78%) or sodium chloride (respectively by 0.18%, 0.36% and 0.54%), resulting in seven diets with total sodium and chloride levels of 0.16% and 0.23%, 0.23% and 0.23%, 0.30% and 0.23%, 0.37% and 0.23%, 0.23% and 0.33%, 0.30% and 0.44%, 0.37% and 0.55% respectively. Increasing sodium level improved feed conversion ratio (FCR) linearly and quadratically. However, when FCR was calculated without adjusting for feed intake of mortalities, the enhanced sodium level did not improve this parameter. Increasing sodium level via sodium chloride enhanced ascites mortality, total mortality, relative weight of heart and right ventricle linearly. Increasing sodium level reduced serum calcium and enhanced serum phosphorus linearly; however, there was a linear tendency to increase tibia ash when sodium level was enhanced by sodium bicarbonate (p = 0.08) or sodium chloride (p = 0.07). Increasing sodium level via sodium bicarbonate tended (p = 0.08) to reduce tibia strength linearly. In conclusion, a diet with 0.16% sodium and 0.23% chloride is enough for broiler chicken reared in a high‐altitude area, and increasing dietary sodium level via sodium chloride has detrimental effect on survivability of broiler in such condition.  相似文献   
40.
在150 mmol·L-1 NaCl胁迫下,研究了喷施不同浓度硝普钠(SNP)对青燕1号(Avena sativa cv. Qingyan No.1)、青引2号(A. sativa cv. Qingyin No.2)、林纳(A. sativa cv. Lena)3种燕麦苗期的叶绿素、丙二醛(MDA)、超氧化物歧化酶(SOD)、过氧化物酶(POD)及过氧化氢酶(CAT)的活性的影响。结果表明,不同浓度(0.05、0.10、0.20 mmol·L-1)的硝普钠使3种燕麦的叶绿素含量、SOD、POD和CAT活性较单盐组显著增加(P0.05),MDA含量显著降低,不同程度地缓解了盐胁迫(150 mmol·L-1 NaCl)对燕麦造成的伤害,而且这种缓解作用存在剂量效应,以0.10 mmol·L-1的处理效果最显著(P0.05),且品种间存在差异,对青引2号的缓解作用最强。  相似文献   
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