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951.
952.
AIM:To investigate the possible mechanism of deferoxamine on angiogenesis in rat hypoxic-ischemic encephalopathy (HIE). METHODS:SD rats (7 days of age) were used to make HIE model. Model group and treatment group were injected with deferoxamine or normal saline alone 24 hours before hypoxic-ischemic insult. Rats were sacrificed at 1,3,7 or 14 days after hypoxic-ischemic insult. Brain capillary density index (BCDI),the number of proliferating capillary,brain water content and extent of brain atrophy were determined. The expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α(HIF-1α) mRNA was measured. RESULTS:Early water content and late atrophic ratio of the left brain were significantly improved in the treatment group compared to model group (P<0.01). The number of proliferating capillary in the treatment group was significantly higher than that in the model group [(2.01±0.31)/HPF vs (0.90±0.25)/HPF,P<0.01]. Deferoxamine markedly up-regulated the expression of VEGF and HIF-1α mRNA in the brain [VEGF at 12 h: (1.41±0.07) vs (1.10±.15),P<0.05; HIF-1α at 12 h: (1.49±0.12) vs (1.11±0.16),P<0.05].CONCLUSION:Deferoxamine may promote angiogenesis and attenuate hypoxic-ischemic induced brain injury via up-regulation of HIF-1α and VEGF expression. 相似文献
953.
YIN Wei HUANG Yi-jun PI Rong-biao SU Xing-wen ZHAO Ling-zhi QIU Peng-xin YAN Guang-mei 《园艺学报》2007,23(11):2141-2146
AIM: To Screen and identify differentially expressed genes that involved in apoptosis model in rat cerebellar granule neurons (CGNs).METHODS: The rat cerebellar granule neurons were isolated and primarily cultured.Fluorescent differential display RT-PCR (FDD RT-PCR) was performed to screen differentially expressed ESTs in the apoptosis model of primarily cultured rat CGNs.ESTs were subcloned into pGEM-T EasyTM vector and then sequenced.Alignment assay in non-redunant database was applied for encoding information.Reverse Northern blotting was used to appraise the results from DDRT-PCR.RESULTS: 164 pieces of differentially expressed ESTs were obtained by FDDRT-PCR.17 of them were subcloned and sequenced.5 ESTs of 17 were confirmed to be positive results by reverse Northern blotting.CONCLUSION: DD-PCR is a rapid,simple-operation and sensitive method for screening differentially expressed genes,which would contribute to the molecular mechanisms of apoptosis/survive of CGNs. 相似文献
954.
955.
桑天牛卵啮小蜂(Aprostocetus prolixus)有孤雌生殖现象,其后代几乎为雄性。沃尔巴克氏体(Wolbachia)是广泛分布于节肢动物体内的一类共生菌,参与多种调控寄主的生殖活动机制。通过对外膜蛋白基因(wsp)、细菌细胞分裂蛋白基因(ftsZ)和核糖体16S rDNA基因的特异性扩增,在米蛾(Corcyra cephalonica Stainton)的DNA中分别扩增出约600、1000和900 bp的片断,验证了米蛾体内已感染了Wolbachia;而在桑天牛卵啮小蜂的DNA中未扩增出任何片断,表明Wolbachia在桑天牛卵啮小蜂体内未被感染或感染率极低。 相似文献
956.
957.
花后温度和湿度条件对台农1号杧坐果率的影响 总被引:2,自引:0,他引:2
为探索杧果坐果率与开花后温度和湿度条件的关系,以台农1号杧为试材,应用生物统计学方法计算分析了80个温度和湿度自变量与不同时期坐果率的相关关系。结果表明:(1)花后14d的坐果率受温度和湿度条件影响最大。(2)花后7d两性花坐果率与花后1~6d平均空气相对湿度呈显著直线线性负相关,与花后1~2d、1~4d、1~6d的平均最高温度、平均温度、平均最低温度、>10℃积温无显著相关关系。(3)花后14d坐果率与花后6~10d的平均最高温度、4~10d平均温度、2~10d平均最低温度、4~14d>10℃积温呈显著或极显著的直线相关;与花后1~14d平均最高温度、平均温度呈显著的多项式线性相关;与花后1~14d平均空气相对湿度呈极显著的直线线性负相关。(4)花后25d坐果率与花后1~10d的平均最高温度、平均温度、>10℃积温以及花后1~14d平均最高温度呈显著的多项式线性相关。(5)有利于花后14d坐果的花后4~14d的下限平均温度为20.6℃,最适温度为24.7℃。 相似文献
958.
7个红壤柑桔园土壤剖面形态特征及其26个土样的有效微量元素含量研究表明,柑桔土壤有效土层分化有3个层次,各层次的形态有自已的特征;土壤剖面中有效B、Zn、Mo严重缺乏,部分果园由于长期使用含Cu杀菌剂而使土壤剖面中有效Cu含量过高;有效B、Cu在土壤剖面中分布自上而下存在明显的递减性,而有效Zn、Mn、Mo分布无明显规律。建议在红壤柑桔园上增施B、Zn、Mo肥,控制喷施含Cu杀菌剂。 相似文献
959.
AIM: To study the effect of Yiqi Huoxue Jiedu Fang (YHJ), composed of ginsenoside, penex notogingseng and berberin, on tumor growth and metastasis and to explore its mechanism.METHODS: Murine Lewis lung carcinoma transplant model was established and mice were treated with YHJ by intraperitoneal injection. After 10 days, the inhibitory rate of tumor, pathology of tumor and PCNA of tumor cells were detected. After 20 days, numbers of metastatic foci on lung surface and microvessel density (MVD) were determined. Expression of VEGF in tumor and serum were also analyzed by immunohistochemical test and ELISA, respectively. RESULTS: YHJ reduced the weight of tumor and the amount of metastatic foci. The inhibitory rates of tumor at high and low dose of YHJ (24 mg·kg-1·d-1, 12 mg·kg-1·d-1) were 48.29% and 37.26%, and the number of metastatic foci was 1.67 and 3.50, while control was 6.44. Furthermore, PCNA of tumor cells, MVD of tumor and VEGF expression in serum and tumor were decreased in YHJ treatment goup as compared with control. CONCLUSION: YHJ remarkably inhibits Lewis lung carcinoma growth and metastasis in mice. Its mechanism may be related to inhibition of angiogenesis. 相似文献
960.
ZHU Hong-bo ZHUO Wen-ying HE Chao HUANG Xue-feng ZHU Yu-ping WANG Da FANG Bing-liang 《园艺学报》2007,23(2):231-235
AIM:To evaluate effects of different chemotherapeutic agents on reversing the acquired resistance to TRAIL gene and clarify the involved mechanisms in DLD1-TRAIL/R colon cancer cells. METHODS:Human colon cancer cell line DLD1-TRAIL/R cells that were resistant to TRAIL-expressing adenovector (Ad/gTRAIL) were treated with Ad/gTRAIL combined with different chemotherapeutic agents. Then, the cell viability was measured by MTT method, and apoptotic signaling conditions, including activation of caspase-3 and caspase-8, expression of Bax and Bcl-XL, were measured by Western blotting analysis. RESULTS:In vitro data showed that several chemotherapeutic agents, including 5-fluorouracil (5-FU) and mitomycin c (MMC), overcome the acquired resistance to TRAIL gene in DLD1-TRAIL/R colon cancer cells. The combination of Ad/gTRAIL and 5-FU effectively suppressed tumor growth in vivo in subcutaneous tumors established from DLD1-TRAIL/R cells. Further data showed that treatment with the combination of Ad/gTRAIL and 5-FU or MMC led to enhance the activation of caspase-3. Moreover, MMC but not 5-FU induced overexpression of Bax gene that was sufficient to overcome the resistance to TRAIL gene in DLD1-TRAIL/R cells. CONCLUSION:Chemotherapeutic agents, such as 5-FU and MMC, overcome the acquired resistance to TRAIL gene in DLD1-TRAIL/R cells. The candidate mechanisms for MMC but not 5-FU to overcome this resistance might involve the induction of over-expressed Bax protein in DLD1-TRAIL/R cells. 相似文献