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901.
成年小鼠雄性生殖细胞的冷冻保存 总被引:1,自引:0,他引:1
在含10%小牛血清(NBS)的DMEM培养基中,分别各添加5%,10%,15%,20%和25%的二甲基亚砜(DMSO),丙二醇(PG),乙二醇(EG)和甘油(G),对成年小鼠睾丸生殖细胞冷冻保存;复苏后台盼蓝染色测定细胞复苏率。结果显示,5%-25%DMSO冻存液组的细胞复苏率分别为88.5%,88.0%,65.6%及51.3%;5%-25%PG冻存液组的细胞复苏率分别为87.2%,86.4%,79.0%,73.4%及40.1%.;5%-25%EG冻存液组的细胞复苏率分别为6.6%,80.9%,60.8%,51.3%及30.0%;5%-25%G冻存液组的细胞复苏率分别为86.5%,86.3%,65.3%,36.0%及31.4%。其中各抗冻剂5%和10%组的细胞复苏率最高,与15%组相比均存在显著或极显著差异。4种抗冻剂的最高细胞复苏率之间无显著差异。DMSO,PG,EG和G分别冷冻保存成年小鼠睾丸生殖细胞对的最小损失率分别为4.8%,6.1%,6.7%,6.8%。结果表明,采用慢速冷冻时,DMSO,PG,EG及G均适宜用作成年小鼠睾丸生殖细胞的抗冷冻剂,最佳使用含量均为5%-10%。成年小鼠睾丸生殖细胞分别在含5%-10%的DMSO,PG,EG和G的DMEM(含10%NBS)冻存液中,2步慢速降温,液氮储存,37℃水浴复苏,是一种具有较高复苏率的冷冻保存方法。 相似文献
902.
测定了家蚕夏芳、长灰A和大造各品种血液、消化液中酸性核糖核酸酶及家蚕秋白、夏芳、长灰A和大造各品种天冬酰胺酶性变化。结果表明:各品种血液、消化液中酸性核糖核酸酶、天冬酰胺酶活性变化随发育呈现较强的规律性,血液中,4龄第3d、5龄第3d这两种酶均出现峰值,4龄眠前活性较低,消化液中,5龄第3d这两种酶活性均较高,不同品种这两种酶活性峰值出现时间有差异;各品种血液中酸性核糖核酸酶、天冬酰胺酶性均明显高于相应品种消化液中这两种酶活性;各品种之间血液、消化液中这两种酶活性有明显差异。 相似文献
903.
904.
为了证明梅花鹿铜缺乏综合征的发生与饲料铜含量的关系,以含铜3.33×10-6的日粮饲喂131只幼龄圈养梅花鹿,于28个月后开始发生铜缺乏综合征,继续饲喂到39个月时,其显症率达9.16%。人工复制的梅花鹿铜缺乏综合征的临床症状与自然发生者相一致,主要为患鹿后躯运动失调,渐进性瘫痪;意识清楚,无癫痫、抽搐症状发生;被毛颜色变淡,眼睛周围出现白眼圈。RBC为(7.56±0.83)×1012/L,Hb(163.30±12.90)g/L,血清铜蓝蛋白氧化酶(25.73±6.45)IU/L,均显著低于对照组。血清铜(5.62±0.80)μmol/L,毛铜(4.55±1.28)mg/kg,均显著低于对照组;血清铁(28.48±2.47)μmol/L,显著高于对照组。主要病理变化为脑、脊髓神经脱髓鞘;部分神经元变性坏死;血管壁肥厚,内膜粗糙,管腔变窄,脆性增加;肝、脾、淋巴结含铁血黄素沉着及骨质疏松。日粮中铜含量为7.33×10-6时,梅花鹿发育良好,体质健壮,生产性能优越,无铜缺乏综合征发生。表明这一铜含量可作为梅花鹿铜元素饲养标准的参考值。 相似文献
905.
复合酶对肉仔鸡生产性能及代谢的影响 总被引:5,自引:2,他引:3
选取1日龄AA肉仔鸡80只,随机分成二组,研究日粮添加和不添加复合酶对肉仔鸡生产性能、代谢及免疫的影响。结果表明:复合酶使肉仔鸡日增重提高7%~7.7%,料肉比降低了4.5%~4.9%,但采食量增加不显著;血液中尿酸和血糖浓度显著下降,血浆胰岛素与血清T3浓度显著提高,提示复合酶改善了肉仔鸡营养物质的吸收与代谢;此外,血清蛋白和血浆IgG水平高于对照组,表明复合酶促进了免疫功能 相似文献
906.
907.
Lee YC Leu SJ Hung HC Wu HH Huang IJ Hsieh WS Chiu WT Hsieh MS Cheng TF Yang YY 《Veterinary immunology and immunopathology》2007,117(1-2):75-85
Severe acute respiratory syndrome (SARS) is a newly emergent human disease, which requires rapid diagnosis and effective therapy. Among antibody sources, immunoglobulin Y (IgY) is the major antibody found in chicken eggs and can be used as an alternative to mammalian antibodies normally used in research and immunotherapy. In this study, phage-expressing chicken monoclonal scFv antibody was chosen and characterized with phage display antibody technology. Truncated fragments of SARS-CoV spike protein were cloned in pET-21 vector and expressed in BL-21 Escherichia coli (E. coli) cells. After purification, the purity of these recombinant spike proteins was examined on SDS-PAGE and their identity verified with Western blot analysis using anti-his antibodies and sera from convalescent stage SARS-CoV-infected patients. Using these bacteria-derived proteins to immunize chickens, it was found that polyclonal IgY antibodies in the egg yolk and sera were highly reactive to the immunogens, as shown by Western blot and immunocytochemical staining analysis. A phage displaying scFv library was also established from spleen B cells of immunized chicken with 5 x 10(7) clones. After four panning cycles, the eluted phage titer showed a 10-fold increase. In sequence analysis with chicken germline gene, five phage clones reacted, with large dissimilarities of between 31 and 62%, in the complementarity-determining regions, one dominant phage 4S1 had strong binding to fragment Se-e, located between amino acid residues 456-650 of the spike protein and this particular phage had significantly strong binding to SARS-CoV-infected Vero E6 cells. Based on the results, we conclude that generating specific scFv-expressing phage binders with the phage display system can be successfully achieved and that this knowledge can be applied in clinical or academic research. 相似文献
908.
909.
910.
CHANG Cheng JIN Peng ZHENG Wei KANG Hua-li DENG Meng-yang LI Shuang-fei WU Xiao-jing 《园艺学报》2015,31(1):12-17
AIM: To study the expression of Jagged2/Notch3 signaling molecules in pulmonary vascular wall of pulmonary hypertensive rats induced by monocrotaline. METHODS: SD rats were randomly divided into normal control group (C group,n=15), solvent control group (S group,n=15) and monocrotaline model groups (M group,n=15). The model of pulmonary hypertension was established by a single subcutaneous injection of monocrotaline (50 mg/kg). The rats in S group were given a single subcutaneous injection of the same dose of solvent. After 4 weeks, the pulmonary vascular remodeling was assessed by HE staining, and the mean pulmonary artery pressure (mPAP) and right ventricular systolic pressure (RVSP) were determined by right heart catheterization. The expression of Jagged2/Notch3/Hes5 molecules in the pulmonary vascular wall was detected by immunohistochemical method and real-time PCR. RESULTS: Compared with S group and C group, the percentage of medial wall thickness of smaller arteries in model group increased significantly (P<0.01). The levels of mPAP and RVSP in M group were significantly higher than those in S group and C groups (P<0.01). The results of real-time PCR showed that the expression of Jagged2, Notch3 and Hes5 was significantly increased in M group compared with S group and C group. The data from immunohistochemical detection indicated that Jagged2 mainly expressed in the intima of small lung artery, Notch3 and Hes5 mainly expressed in the medial smooth muscle cells. Compared with S group and C group, the expression of Jagged2 and Notch3 was significantly increased in the lung small arteries of M group. CONCLUSION: The activation of Jagged2/Notch3 signaling pathway might play an important role in the formation of pulmonary hypertension. 相似文献