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81.
以ITS测序与SCAR分子标记相结合的香蕉病原菌FOC4分子检测方法,利用通用引物ITS1和ITS4对病原菌SF001的rDNA中ITS序列进行PCR扩增,获得560bp左右的特异条带。经Blast分析比对,确定该菌为FOC。再利用FOC4的特异引物PCL/PDL对基因组上的特征序列扩增区域(SCAR)进行PCR扩增,获得677bp的特有序列,鉴定菌株SF001是尖孢镰刀菌古巴专化型4号生理小种。经过致病性测试,菌株SF001表现出典型4号生理小种的病理特征。 相似文献
82.
以紫龙角的不同器官为试材,研究不同植物生长调节剂浓度及组合、培养基、光照、外植体等因素对其愈伤组织诱导和植株再生的影响。结果表明:愈伤组织诱导的最佳外植体是不带腋芽茎块,在麦基1号+CH+6-BA 1.0~1.8mg/L+2,4-D 0.5~2.0mg/L的培养基上,暗培养6d时诱导率高达90%以上;质地紧密,有一定疏松度,是建立细胞无性系的优良材料。带腋芽茎块是直接诱导丛生芽的理想外植体,H+TDZ 4mg/L+NAA 0.4mg/L培养基适合丛生芽生长、增殖诱导率达到91%。复壮增殖不定芽的培养基为改良的H+TDZ 4mg/L+NAA 0.4mg/L;1/2MS+NAA 2.5mg/L是最佳生根培养基,每个不定芽平均有效根数最高为6.17个。 相似文献
83.
芋优异种质资源鉴定评价研究 总被引:1,自引:0,他引:1
对农业行业标准《农作物种质资源鉴定评价规范芋》编制的技术路线进行了分析研究,以期为芋优异种质资源的鉴定评价提供参考。 相似文献
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研究了多菌灵对茶树菇和食用菌生产中3大主要污染霉菌菌丝生长的影响.在PDA培养基上多菌灵对茶树菇菌丝和孢菌、木霉及曲霉菌丝的EC50分别为22.3μg·mL-1、0.06μg·mL-1、0.29μg·mL-1和0.64μg·mL-1,MIC分别为60μg·mL-1、0.9μg·mL-1、1.6μg·mL-1和2.0μg·mL-1;在出菇袋料培养基中,按1500、11000和12000添加多菌灵对茶树菇菌丝生长影响不明显.同时采用液相色谱法分析了多菌灵在茶树菇子实体中的残留,3种处理的残留量分别为0.09ppm、0.04ppm和0.01ppm. 相似文献
86.
AIM: To investigate the pattern of Th1/Th2 balance in systemic lupus erythematosus(SLE) patients and the relationship between CD28/CTLA-4(cytotoxic T-lymphocyte antigen-4) molecule expression and Th1/Th2 balance.METHODS: Eighteen SLE patients met the ARA 1997 updated SLE criteria were selected in the study. According to Bombardier's SLEDAI criteria, all patients were classified into two groups: active group(12 cases) and static group(6 cases). Fourteen normal individuals, matched for age and sex of the patients, served as controls. The peripheral blood mononuclear cells(PBMCs) were isolated by density gradient centrifugation and cultured in RPMI-1640 culture medium. After treated with PMA(5 μg/L) and ionomycin(500 μg/L) for 72 h, the PBMCs were collected, the contents of IFN-γ and IL-10 in the supernatant of cultured PBMCs were detected using enzyme linked immunosorbent assay(ELISA). The expression of CD28 and CTLA-4 molecules on T cells were detected by flow cytometric technique with double staining by FITC or PE labeled monoclonal antibodies. RESULTS: The level of IL-10 was higher in the PBMCs of active and static SLE patients(351.29 ng/L±153.31 ng/L and 319.37 ng/L±153.39 ng/L) than that in controls(254.48 ng/L±120.69 ng/L), but the difference did not reach statistical significance(P>0.05). The level of IFN-γ was significantly lower in the PBMCs of active SLE patients(25.76 ng/L±16.09 ng/L) than that in controls(50.71 ng/L±27.92 ng/L, P<0.05). The ratio of IL-10/IFN-γ was significantly higher in active SLE patients(18.74±13.77) than that in controls(6.66±4.95, P<0.05). Either before or after culture, the expression of CD28 molecule on CD3+and CD8+ T cells from all SLE patients was not remarkably different from that in the cells of controls. Before culture, the expression of CTLA-4 molecule on CD3+T cells of active SLE patients(0.79%+0.37%) was significantly lower than that in the cells of controls(1.31%+0.61%, P<0.05). After culture, the expression of CTLA-4 molecule on CD3+ T cells of SLE patients was still lower than that in the cells of normal controls without statistical significance(P>0.05).The expression level of CD28 molecule on CD3+ or CD8+ T cells in active SLE patients and controls was not correlated with the levels of IFN-γ and IL-10 in the supernatants(P>0.05). The level of CTLA-4 molecule expression on CD3+ T cells of active SLE patients was positively correlated with IFN-γ level(r=0.681, P<0.05), while was negatively correlated with IL-10 levels(r=-0.624,P<0.05) and the ratio of IL-10/IFN-γ(r=-0.738, P<0.01). The level of CTLA-4 molecule expression on CD3+ or CD8+ T cells of controls showed no correlation with IFN-γ levels, while showed negative correlations with IL-10 level(r=-0.587, P<0.05; r=-0.563, P<0.05, respectively).CONCLUSION: There is a bias in the differentiation of Th0 cells towards Th2 in SLE patients. CTLA-4 probably plays an important role in this mechanism through suppressing the signal transmitted by CD28. 相似文献
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AIM:To investigate expression and function of CD40 ligand by peripheral blood mononuclear cells (PBMCs) in patients with systemic lupus erythematosus (SLE).METHODS:Expression of CD40 ligand by PBMCs in patients with SLE and control were examined by flow cytometric analysis before and after stimulated by phytohemagglutinin(PHA)and depressed by Dexamethasone(Dex). The correlation between expression of CD40 ligand and SLE activity index(SLEDAI) was analysed in patients with SLE.RESULTS:The expression of CD40 ligand by PBMCs in patients with active SLE was higher than that in patients with inactive SLE and control. Though the expression of CD40 ligang by PBMCs could be stimulated by PHA in three groups, it was the highest in patients with active SLE. Dex depressed the expression of CD40 ligand by PBMCs significantly in patients with SLE, but not in control. There was high positive correlation between expression of CD40 ligand and SLEDAI in patients with active and inactive SLE.CONCLUSION:Increased expression of CD40L by PBMCs in patients with SLE may play an important role in pathogenesis of SLE. 相似文献