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11.
自噬是将功能异常或不需要的胞内组分降解的细胞学过程,广泛参与真核生物的生长发育过程、对营养缺乏的响应及生物/非生物胁迫反应。NBR1 (Next to BRCA1 gene 1, NBR1)是在植物中发现的最重要的自噬受体,但有关植物NBR1类自噬受体的研究较少,水稻中此类蛋白的研究还是空白。本文通过RT-PCR方法,从水稻日本晴幼苗的cDNA中克隆到一个含有泛素相关结构域(Ubiquitinassociated,UBA)的基因,将其命名为OsUBA。OsUBA的开放阅读框长2538 bp,编码845个氨基酸残基。OsUBA属于水稻中的NBR1类蛋白。OsUBA的启动子区有多个与光、逆境胁迫及激素反应相关的元件; OsUBA基因在水稻花药、正在萌发的种子以及根中的表达量较高,在茎和叶中也有表达; 200μmol L~(–1) ABA处理显著抑制OsUBA的表达,100μmol L~(–1) GA处理后OsUBA的表达略有升高。对OsUBA过表达水稻株系的研究表明,转基因水稻种子的萌发比野生型更快, ABA (3μmol L~(–1))处理显著抑制OsUBA过表达水稻株系种子的萌发, GA (100μmol L~(–1))处理对OsUBA过表达水稻株系种子的萌发略有促进;OsUBA过表达水稻株系的开花时间较野生型明显提前。这些结果表明,水稻NBR1蛋白基因OsUBA的表达和功能可能与对开花时间和种子萌发的调控以及生物/非生物胁迫反应有关。 相似文献
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云南怒江傈僳族自治州古树名木资源现状调查 总被引:1,自引:0,他引:1
对怒江傈僳族自治州人为活动区域古树名木资源现状进行调查。结果表明:共记录到古树名木496株,涉及36科54属76种,其中有8种国家重点保护野生植物,分别为澜沧黄杉、秃杉、南方红豆杉、云南榧树、千果榄仁、红椿、光叶珙桐和香果树;怒江州古树名木主要分布在乡村街道及远郊野外,占总数的98.8%,63.6%的古树生长在海拔1500~1999 m;古树名木的生长环境及长势总体较好,但保护力度相对薄弱,应采取相关措施加强保护和管理。 相似文献
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旨在确定盐酸多西环素片按照给药说明给药后在羔羊体内的残留消除规律及休药期。将盐酸多西环素片根据体重以5 mg·kg-1内服给药,间隔24 h,连续给药5次。在最后1次给药后,分别在第0(12小时)、1、2、3、5、7和9天时间点采集羔羊脂肪、肌肉、肝和肾,采用建立并验证的HPLC-VWD方法测定组织中多西环素的含量。结果显示:方法学考察结果表明,在50~5 000 ng·mL-1添加的线性方程和相关系数为y=0.044x-0.414,R2=0.999。试验结果表明,多西环素在羔羊组织中代谢快速,最后1次给药后第9天,在肌肉、肝、肾和脂肪中均未检测到多西环素。本试验以5 mg·kg-1体重内服给予羔羊盐酸多西环素片后,根据欧洲药品评估机构法规《EMEA/CVMP/036/95》,建议盐酸多西环素片在羔羊组织中的休药期为2 d。 相似文献
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Canine babesiosis due to Babesia gibsoni (B. gibsoni) displays severe clinical manifestations. Recurrence of babesiosis after anti-babesial treatment is observable in over 10 % of the patients. The present study ascertains the risk factors and cumulative incidence of recurrence of canine babesiosis. For a sample of 145 dogs diagnosed with acute babesiosis, the following parameters were assessed over a period of 16 weeks: haematological parameters, status of anaemia, platelet count, total WBC count, haemoglobin concentration and RBC count, concurrent haemoparasitism, and secondary immune mediated haemolytic anaemia (IMHA). Patient demographics such as age, breed, sex were also recorded. The potential risk factors were statistically evaluated by the cumulative incidence function and the Kaplan-Meier method. The recurrent infections were observed in 11.8 % of the study sample. The following factors were found to associate with increased risk of recurrence: Rottweiler breed (CIR 21.8 % ± 6.9 %; p < 0.05), secondary IMHA (CIR 28.7 % ± 11.3 %; p < 0.05), RBC counts < 2 × 106/μl on the day of diagnosis (CIR 16 % ± 4.6 %; p < 0.05), and persistent anaemia over 20 days post treatment (CIR 29.14 ± 7.9 %; p < 0.001). Dogs with concurrent haemoparasitic infections were predicted to have a fatal outcome in the survival analysis (disease related mortalities 25 % ± 13 %; p < 0.001). According to the findings, veterinarians need to pay attention to Rottweiler breed, dogs with secondary IMHA, concurrent haemoparasitism, low RBC counts on diagnosis and those with persistent anaemia to reduce the risk of relapse. 相似文献
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Responses of carbon metabolism and antioxidant system of summer maize to waterlogging at different stages 下载免费PDF全文
A field experiment was performed to explore responses of carbon metabolism, antioxidant system and endogenous hormone content of summer maize hybrids DengHai605 (DH605) and ZhengDan958 (ZD958) to waterlogging at the third leaf stage (V3), the sixth leaf stage (V6) and the 10th day after the tasselling stage (10VT). Results showed that waterlogging significantly decreased the contents of zeatin riboside (ZR), indole‐3‐acetic acid (IAA) and gibberellic acid (GA), compared to those of CK. However, leaf abscisic acid (ABA) content was significantly increased by waterlogging at different stages, with the most significant increase was found in the treatment of waterlogging at V3 (V3‐W), with an increase of 30% and 29% for DH605 and ZD958, respectively. Waterlogging significantly decreased antioxidative enzyme activities, accelerating leaf senescence, resulted in the disorder of leaf gas exchange parameters and chlorophyll fluorescence parameters. In addition, waterlogging decreased key enzyme activities of carbon metabolism (ribulose bisphosphate carboxylase and phosphoenolpyruvate carboxylase), with the most significant reduction in V3‐W, with a decrease of 46% and 49% for DH605, and 53% and 55% for ZD958, respectively. Visibly, waterlogging disturbed carbon metabolism, affected plant endogenous hormone content, accelerated leaf senescence and eventually resulted in a significant reduction in photosynthetic characteristic and grain yield. V3 was most susceptible to waterlogging, followed by V6 and 10VT. 相似文献
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M. Torfi Mozanzadeh V. Yavari J.G. Marammazi N. Agh E. Gisbert 《Aquaculture Nutrition》2017,23(3):470-483
Four isonitrogenous diets containing different carbohydrate:lipid (CHO:L) ratios (0.3, 0.6, 1.1 and 1.8) were tested in triplicate groups (16 fish per replicate) of silvery‐black porgy juveniles for 8 weeks. Growth performance was not affected by different dietary CHO:L ratios (P > 0.05); however, the viscerosomatic index, the intraperitoneal fat, whole‐body lipid, energy and n‐3 long chain polyunsaturated fatty acids levels increased with decreasing dietary CHO:L ratios (P < 0.05). Fish fed with 1.8 CHO:L diet had the lowest apparent digestibility coefficients of protein and lipid, as well as the lowest plasma haemolytic and lysozyme activities (P < 0.05). Red blood cell counts and plasma glucose levels were higher in fish fed with 1.1 and 1.8 CHO:L ratio diets than in the other groups (P < 0.05). Plasma alkaline phosphatase and alanine aminotransferase, as well as the level of lipid peroxidation and total antioxidant capacity in the liver and plasma increased as dietary CHO:L ratios decreased (P < 0.05). The results of the current study indicated that the diets with CHO:L ratios between 0.6 and 1.1 are optimal for silvery‐black porgy, whereas higher ratios may result in hyperglycaemia and immune suppression, and lower CHO:L ratios may lead to oxidative stress and liver dysfunction. 相似文献