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蛋白质饲料木聚糖含量及其体外酶解效果研究 总被引:6,自引:0,他引:6
本文通过体外酶解试验,考察木聚糖酶对豆粕、菜籽粕和棉籽粕的总木聚糖和水溶性木聚糖的降解效果,试图建立木聚糖酶与不同蛋白质饲料种类的定量关系.试验结果表明:①不同蛋白质饲料的总木聚糖和水溶性木聚糖的含量不同,豆粕、菜籽粕和棉籽粕的总木聚糖含量分别为5.62%、6.56%和8.20%;水溶性木聚糖含量分别为0.35%、0.97%和0.84%;②不同来源的3种蛋白质饲料的总木聚糖和水溶性木聚糖含量变异较小.在适宜的水环境中,菜籽粕的水溶性木聚糖含量显著增加,豆粕和棉籽粕的水溶性木聚糖变化不大;③木聚糖酶对3种蛋白质饲料的总木聚糖均有显著降解作用,对水溶性木聚糖有一定的降解作用,其中对菜籽粕的总木聚糖和水溶性木聚糖的降解作用均较大;以总木聚糖酶为标识,结合考虑成本,豆粕、菜籽粕、棉籽粕的适宜添加木聚糖酶水平分别为1 000、1 000和1 500 U/kg. 相似文献
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Byeong-Teck Kang Jong-Hwan Lee Dong-In Jung Chul Park Su-Hyun Gu Hyo-Won Jeon Dong-Pyo Jang Chae-Young Lim Fu-Shi Quan Young-Bo Kim Zang-Hee Cho Eung-Je Woo Hee-Myung Park 《Journal of veterinary science (Suw?n-si, Korea)》2007,8(4):369-376
The aim of the present study was to assess the clinical and histopathological findings in a canine model of ischemic stroke. Cerebral ischemic stroke was induced by middle cerebral artery occlusion in four healthy beagle dogs using silicone plugs. They showed neurological signs of forebrain dysfunction such as reduced responsiveness, head turning, circling, postural reaction deficits, perceptual deficits, and hemianopsia. These signs gradually regressed within 4 weeks without therapy. On magnetic resonance imaging, T2 hyperintensity and T1 hypointensity were found in the cerebral cortex and basal ganglia. These lesions were well-defined and sharply demarcated from adjacent brain parenchyma with a homogenous appearance. No abnormalities of the cerebrospinal fluid were observed. At necropsy, atrophic and necrotic lesions were observed in the cerebral cortex. The cerebral cortex, basal ganglia, and thalamus were partially unstained with triphenyl-tetrazolium chloride. Histopathologically, typical features of infarction were identified in cortical and thalamic lesions. This study demonstrates that our canine model resembles the conditions of real stroke patients. 相似文献
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本试验采用SephadexG-200层析技术纯化猪囊尾蚴(Cysticercus cellulosae)的囊液粗抗原。共获得两种(CF1、CF2)层析抗原,以酶联免疫吸附试验(ELISA)判定抗原的最适包被浓度以及抗体的最适稀释倍数,各阶段最适反应条件,结果证明CF1具有特异性强、敏感性高、稳定性好、重复性强的特点可以作为免疫诊断囊尾蚴病猪IgG。 相似文献
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采用白细胞介素-6依赖细胞株B9建立了鸡白细胞介素-6活性的MTT检测方法。每孔培养细胞数在2.5×103~4×104范围内D值与细胞数显示有良好的线性关系,MTT的最佳保留时间为4 h,最低检测限为0.1 U/mL。应用该方法检测了健康艾维茵肉鸡25例,血清chIL-6活性为(4.33±0.75)U/mL,而25例葡萄球菌病患鸡血清chIL-6的活性为(14.05±6.87)U/mL,与健康肉鸡比较差异极显著(P<0.01),为该方法进一步临床应用奠定了基础。 相似文献
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弓形虫两种保种方法的试验 总被引:1,自引:0,他引:1
目的寻求一个简便、适宜的弓形虫保种方法。方法采用不同温度的冷冻保存法和细胞培养保存法对弓形虫保存进行了试验研究,为深入研究弓形虫提供保证。结果弓形虫在液氮(-196℃)、-70℃能长期保存,4℃能保存14 d。通过细胞培养能获得大量的弓形虫滋养体,对培养细胞的选择性不强。结论两种保种方法保存后弓形虫毒力不变。 相似文献
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WU Quan XIAO Xiang-qian LIU Shu-ye LIU Yu SHI Jian-dang WANG Ke-ming ZHANG Ju 《园艺学报》2007,23(7):1382-1387
AIM: To characterize the effect of estradiol on proliferation, differentiation and extracellular matrix (ECM) accumulation in stromal cells through regulation of BPH-1 paracrine. METHODS: BPH-1 cells were stimulated with different concentrations of estradiol. Conditioned media (CM) were harvested and their effects on stromal cell cultures were tested. Cell proliferation was determined by MTT assay. mRNA of smoothelin, fibronectin, collagen Ⅳ and transforming growth factor β1(TGF-β1) were analyzed by real-time RT-PCR. Western blotting was used to determine smooth muscle myosin heavy chain (SMMHC). ELISA and radioimmunoassay were respectively used to measure fibronectin, TGF-β1 and collagen Ⅳ protein expressions.RESULTS: Estrodiol stimulated the expression and secretion of TGF-β1 in BPH-1 cells. The proliferation of stromal cells increased when they were cultured with CM harvested from estrogen treated BPH-1 cells. The mRNA levels of collagen Ⅳ and smoothelin increased in stromal cells treated with CM from BPH-1 cells. The results of radioimmunoassay also showed that the collagen Ⅳ protein level up-regulated in the supernatants and cell extracts of CM-treated stromal cells. A neutralizing antibody to TGF-β1 inhibited the stimulation of collagen Ⅳ and SMMHC by BPH-1 CM. The expression of fibronectin was only marginally changed in stromal cells cultured in the presence of BPH-1 CM. CONCLUSION: The BPH-1 cells increase ECM accumulation and differentiation of stromal cells through TGF-β1. Estradiol stimulate differentiation of stromal cells by induction of TGF-β1 expression. Estradiol stimulate proliferation by influencing the factors secreted from prostatic epithelial cells. 相似文献
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