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991.
莲藕膨大过程中淀粉合成相关酶的活性变化及其与淀粉积累的关系 总被引:1,自引:0,他引:1
【目的】研究莲藕根状茎膨大过程中淀粉合成相关酶的活性,探讨其与莲藕淀粉积累的关系。【方法】以4个莲藕主栽品种为试材,采用比色法,分析了根状茎膨大过程中葡萄糖、果糖、蔗糖、可溶性总糖、淀粉含量及腺苷二磷酸葡萄糖焦磷酸化酶(ADPGPase)、淀粉合成酶(SSase)和淀粉分支酶(Q-酶)活性的变化。【结果】果糖、葡萄糖和可溶性总糖、蔗糖的含量高峰分别出现在莲藕根茎的膨大前期、中期、后期。总淀粉、直链淀粉、支链淀粉含量在膨大中期前上升缓慢,到后期含量急增,总淀粉含量可达鲜重的11.1%~12.7%,其中支链淀粉始终约占总淀粉的70%。ADPGPase和SSase 在各相同膨大时期品种间差异明显,而Q-酶差异较小;3种酶表达上存在明显的时段特征,SSase表达最早,膨大前期即达峰值,ADPGPase和Q-酶活性的表达则相对较迟,均在中期达最大值;ADPGPase和SSase的活性峰值与后期总淀粉含量呈极显著和显著正相关,相关系数分别为0.9830(P<0.01;n=12)和0.8458(P<0.05;n=12);Q-酶活性峰值与后期支链淀粉含量呈显著正相关,相关系数为0.7690(P<0.05;n=12)。【结论】ADPG焦磷酸化酶和淀粉合成酶活性对成熟期莲藕根茎的总淀粉含量起关键调控作用;淀粉分支酶则调控根茎支链淀粉的含量。 相似文献
992.
为了进一步探讨中药饮水剂的抗球虫作用机制,将120只14日龄海兰褐蛋公雏,随机分为对照组(I)、感染组(Ⅱ)和中药饮水剂组(Ⅲ),每组40只。除I组外,其余每只鸡口服感染8.0×104个E.tenella孢子化卵囊,分别于感染0、3、6、9、12 d后,每组随机取鸡5只,心脏采血,用于血清一氧化氮(NO)及其合成酶(iNOS)的测定。结果表明,在感染后3 d,各组血清NO含量和iNOS活性无显著差异(P>0.05);在感染高峰期(6 d),Ⅲ组血清NO含量及iNOS活性较Ⅱ组分别降低了36.17%和14.25%,差异极显著(P<0.01),与Ⅰ组比较无显著差异(P>0.05);至感染后9 d,虽然Ⅲ组血清NO含量及iNOS活性与Ⅱ组差异不显著,但仍较其降低了12.53%和13.51%;至感染后12 d,Ⅱ组血清NO含量及iNOS活性基本恢复正常水平。结果提示:中药饮水剂通过抑杀球虫,以减少炎性因子的释放,抑制宿主细胞内iNOS活性及表达,降低血清NO含量。 相似文献
993.
番茄果实采后冷激处理的生理研究 总被引:11,自引:0,他引:11
将绿熟樱桃番茄 (Lycopersicumesculentumvar.cerasiforme)果实采后冷激处理 ,然后贮藏在 (2 0± 1)℃条件下 ,以未经冷激处理的果实为对照 ,研究番茄果实成熟过程中的生理变化。结果表明 ,冷激处理后 ,ACC氧化酶 (ACO)和ACC合成酶 (ACS)的活性上升延缓 ,呼吸和乙烯跃变延迟 ,而叶绿素降解、番茄红素合成和果实的软化速率被抑制。 相似文献
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997.
Keisuke KOYAMA Sung-Sik KANG Weiping HUANG Yojiro YANAGAWA Yoshiyuki TAKAHASHI Masashi NAGANO 《The Journal of reproduction and development》2014,60(2):136-142
The objective of this research was to clarify the aging-related changes in in
vitro-matured bovine oocytes. Firstly, we examined the fertilization and
embryonic development of bovine oocytes after 22 and 30–34 h of in vitro
maturation (IVM). The oocytes after 30–34 h of IVM (penetrated by sperm at around 40 h
after starting IVM) showed a lower developmental rate to blastocysts (P<0.01), although
normal fertilization rates were similar regardless of IVM duration. In the next
experiment, reactive oxygen species (ROS), mitochondrial activity and ATP content in
oocytes after 20, 30 and 40 h of IVM were examined. The lowest level of ROS was found in
the group subjected to 30 h of IVM. The mitochondrial activity and ATP content in the
group subjected to 40 h of IVM were higher than in the group subjected to 20 h of IVM
(P<0.01), and those in the group subjected to 30 h of IVM showed intermediate values.
Thereafter, the mitochondrial activities at 3 days after in vitro
fertilization in embryos derived from the oocytes subjected to 22 and 34 h of IVM were
evaluated. In the group subjected to 34 h of IVM, high-polarized mitochondria were
frequently observed at the periphery of blastomeres. The present results suggest that high
mitochondrial activity observed in oocytes after prolonged IVM culture and localization of
high-polarized mitochondria at the periphery of blastomeres during early embryonic
development may be associated with the low developmental competence in aged bovine
oocytes. 相似文献
998.
本研究以番鸭肝脏为试验材料,通过RT-PCR扩增出番鸭脂肪酸合成酶(fatty acid synthase,FAS)部分CDS序列,利用相关分子生物学软件对其进行分析,同时采用实时荧光定量PCR技术检测FAS基因在成年番鸭各组织中的表达特性及填饲对番鸭肝脏和腹脂中该基因表达的影响。结果表明,克隆出的番鸭FAS基因CDS片段大小为1122 bp,编码374个氨基酸,与近缘物种禽类核苷酸同源性为92%~99%;实时荧光定量PCR结果表明,番鸭FAS基因在肝脏和腹脂中高表达,说明FAS具有组织表达特异性;填饲导致肝脏中FAS基因表达显著升高(P<0.05)。本试验结果可为进一步研究FAS基因在番鸭肝脏脂质代谢中的作用奠定基础。 相似文献
999.
AIM:To explore the dynamic changes of nitric oxide and inducible nitric oxide synthase during the process of atherosclerosis, and to analyze their influence on the formation of atherosclerosis. METHODS:SD rats (n=60) were randomly divided into control group and atherosclerosis group (30 rats in each group). Atherosclerosis model was induced by feeding high-fat diet and vitamin D3. The values of blood biochemical were analyzed enzymatically using bioMérieux kit. The concentration of serum nitric oxideing was detected by a colorimetric method. The success of atherosclerosis modeling was determined by pathological examination. The protein expression of inducible nitric oxide synthase in atherosclerotic plaque was detected by the method of immunohistochemistry. RESULTS:The atherosclerosis model was successfully established in 90 d. The concentration of serum nitric oxide gradually decreased in atherosclerosis group, and a significant difference among groups was observed. Atherosclerosis index was positively correlated with calcium ion, and negatively correlated with nitric oxide. The protein expression of inducible nitric oxide synthase in the atherosclerotic plaque after 90 d was found. CONCLUSION:The protein expression of inducible nitric oxide synthase in the plaque area of aorta increases and the concentration of serum nitric oxide decreases with the process of atherosclerosis. The anti-atherosclerosis role of nitric oxide is gradually decreased. 相似文献
1000.
DING Zhi-bin ZHANG Hui YANG Xing-wang ZHANG Hai-fei YU Jie-zhong LI Yan-hua LIU Chun-yun YANG Wan-fang LI Jun-lian FENG Qian-jin ZHAO Yong-fei XIAO Bao-guo MA Cun-gen 《园艺学报》2014,30(9):1610-1615
AIM:To explore the therapeutic effect of a novel Rho kinase inhibitor WAR5 on the experimental autoimmune encephalomyelitis (EAE) and its possible mechanism. METHODS:Female C57BL/6 mice were randomly divided into EAE group and WAR5 group. EAE model was induced by the application of MOG35-55 peptide. WAR5 was injected intraperitoneally every other day from post-immunization (PI) day 3 to PI day 27. The clinical score and body weight were recorded every other day. On PI day 28, the animals were sacrificed and spinal cords were obtained for HE and myelin staining. The splenocytes were isolated and the expression of CD16/32 and CD206 were analyzed by flow cytometry. The protein extracts from the brains and spinal cords were collected for the measurement of inducible nitric oxide synthase (iNOS) by Western blotting. RESULTS:The administration of WAR5 delayed the onset of EAE and attenuated the clinical symptoms. The results of the pathological examination revealed that WAR5 inhibited the infiltration of inflammatory cells and improved myelination in spinal cords, accompanied with the poralization of M1 macrophages to M2 phenotype in the spleen. WAR5 inhibited the expression of iNOS in the central nervous system, especially in the spinal cords. CONCLUSION:The therapeutic effect of WAR5 on EAE may be related to the shift of M1 macrophages to M2 phenotype and inhibition of inflammation in the central nerve system. 相似文献