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71.
Treatment of tropical forages with exogenous fibrolytic enzymes: effects on chemical composition and in vitro rumen fermentation 下载免费PDF全文
A. Díaz M. J. Ranilla L. A. Giraldo M. L. Tejido M. D. Carro 《Journal of animal physiology and animal nutrition》2015,99(2):345-355
The effects of three treatments of fibrolytic enzymes (cellulase from Trichoderma longibrachiatum (CEL), xylanase from rumen micro‐organisms (XYL) and a 1:1 mixture of CEL and XYL (MIX) on the in vitro fermentation of two samples of Pennisetum clandestinum (P1 and P2), two samples of Dichanthium aristatum (D1 and D2) and one sample of each Acacia decurrens and Acacia mangium (A1 and A2) were investigated. The first experiment compared the effects of two methods of applying the enzymes to forages, either at the time of incubation or 24 h before, on the in vitro gas production. In general, the 24 h pre‐treatment resulted in higher values of gas production rate, and this application method was chosen for a second study investigating the effects of enzymes on chemical composition and in vitro fermentation of forages. The pre‐treatment with CEL for 24 h reduced (p < 0.05) the content of neutral detergent fibre (NDF) of P1, P2, D1 and D2, and that of MIX reduced the NDF content of P1 and D1, but XYL had no effect on any forage. The CEL treatment increased (p < 0.05) total volatile fatty acid (VFA) production for all forages (ranging from 8.6% to 22.7%), but in general, no effects of MIX and XYL were observed. For both P. clandestinum samples, CEL treatment reduced (p < 0.05) the molar proportion of acetate and increased (p < 0.05) that of butyrate, but only subtle changes in VFA profile were observed for the rest of forages. Under the conditions of the present experiment, the treatment of tropical forages with CEL stimulated their in vitro ruminal fermentation, but XYL did not produce any positive effect. These results showed clearly that effectiveness of enzymes varied with the incubated forage and further study is warranted to investigate specific, optimal enzyme‐substrate combinations. 相似文献
72.
Jin-Gu NO Mi-Kyung CHOI Dae-Jin KWON Jae Gyu YOO Byoung-Chul YANG Jin-Ki PARK Dong-Hoon KIM 《The Journal of reproduction and development》2015,61(2):90-98
Pretreatment of somatic cells with undifferentiated cell extracts, such as embryonic stem cells and mammalian oocytes, is an attractive alternative method for reprogramming control. The properties of induced pluripotent stem cells (iPSCs) are similar to those of embryonic stem cells; however, no studies have reported somatic cell nuclear reprogramming using iPSC extracts. Therefore, this study aimed to evaluate the effects of porcine iPSC extracts treatment on porcine ear fibroblasts and early development of porcine cloned embryos produced from porcine ear skin fibroblasts pretreated with the porcine iPSC extracts. The ChariotTM reagent system was used to deliver the iPSC extracts into cultured porcine ear skin fibroblasts. The iPSC extracts-treated cells (iPSC-treated cells) were cultured for 3 days and used for analyzing histone modification and somatic cell nuclear transfer. Compared to the results for nontreated cells, the trimethylation status of histone H3
lysine residue 9 (H3K9) in the iPSC-treated cells significantly decreased. The expression of Jmjd2b, the H3K9 trimethylation-specific demethylase gene, significantly increased in the iPSC-treated cells; conversely, the expression of the proapoptotic genes, Bax and p53, significantly decreased. When the iPSC-treated cells were transferred into enucleated porcine oocytes, no differences were observed in blastocyst development and total cell number in blastocysts compared with the results for control cells. However, H3K9 trimethylation of pronuclear-stage-cloned embryos significantly decreased in the iPSC-treated cells. Additionally, Bax and p53 gene expression in the blastocysts was significantly lower in iPSC-treated cells than in control cells. To our knowledge, this study is the first to show that an extracts of porcine iPSCs can affect histone modification and gene expression in porcine ear
skin fibroblasts and cloned embryos. 相似文献
73.
Involvement of histone H2B monoubiquitination in the regulation of mouse preimplantation development
Masatoshi OOGA Masataka G. SUZUKI Fugaku AOKI 《The Journal of reproduction and development》2015,61(3):179-184
Histone H2B monoubiquitination (H2Bub1) plays an important role in developmental regulation in various vertebrate species. However, the role of H2Bub1 in mammalian preimplantation development remains unclear. In the present study, we examined the role of H2Bub1 in the regulation of mouse preimplantation development. Based on immunocytochemical analysis using an anti-H2Bub1 antibody, no H2Bub1 signal was detected in the metaphase chromosomes of unfertilized oocytes or the pronuclei of early 1-cell stage embryos, but a weak signal was observed in late 1-cell stage embryos. The signal increased after cleavage into the 2-cell stage, and thereafter a strong signal was observed until the blastocyst stage. To assess the significance of H2Bub1 in the regulation of preimplantation development, RNF20 (an H2B-specific ubiquitin E3 ligase) was knocked down using small interfering RNA (siRNAs). In embryos treated with siRNA, the levels of Rnf20 mRNA and H2Bub1 decreased
at the 4-cell and morula stages. Although these embryos developed normally until the morula stage, only one-third developed into the blastocyst stage. These results suggested that H2Bub1 is involved in the regulation of preimplantation development. 相似文献
74.
75.
Avian Influenza A(H5N1) Virus Outbreak Investigation: Application of the FAO‐OIE‐WHO Four‐way Linking Framework in Indonesia 下载免费PDF全文
Misriyah H. A. Pawestri M. Azhar G. Tallis L. Schoonman G. Samaan 《Zoonoses and public health》2015,62(5):381-387
WHO, FAO and OIE developed a ‘four‐way linking’ framework to enhance the cross‐sectoral sharing of epidemiological and virological information in responding to zoonotic disease outbreaks. In Indonesia, outbreak response challenges include completeness of data shared between human and animal health authorities. The four‐way linking framework (human health laboratory/epidemiology and animal health laboratory/epidemiology) was applied in the investigation of the 193rd human case of avian influenza A(H5N1) virus infection. As recommended by the framework, outbreak investigation and risk assessment findings were shared. On 18 June 2013, a hospital in West Java Province reported a suspect H5N1 case in a 2‐year‐old male. The case was laboratory‐confirmed that evening, and the information was immediately shared with the Ministry of Agriculture. The human health epidemiology/laboratory team investigated the outbreak and conducted an initial risk assessment on 19 June. The likelihood of secondary cases was deemed low as none of the case contacts were sick. By 3 July, no secondary cases associated with the outbreak were identified. The animal health epidemiology/laboratory investigation was conducted on 19–25 June and found that a live bird market visited by the case was positive for H5N1 virus. Once both human and market virus isolates were sequenced, a second risk assessment was conducted jointly by the human health and animal health epidemiology/laboratory teams. This assessment concluded that the likelihood of additional human cases associated with this outbreak was low but that future sporadic human infections could not be ruled out because of challenges in controlling H5N1 virus contamination in markets. Findings from the outbreak investigation and risk assessments were shared with stakeholders at both Ministries. The four‐way linking framework clarified the type of data to be shared. Both human health and animal health teams made ample data available, and there was cooperation to achieve risk assessment objectives. 相似文献
76.
H3N2犬流感病毒(canine influenza virus, CIV)已在中国多地的犬群中流行,是禽流感跨宿主感染并形成新分支的近期案例。研究表明,PA-X基因与甲型流感病毒适应新宿主的能力相关,且其长度能够影响甲型流感病毒的复制及致病能力。为了解PA-X基因的长度变化对H3N2 CIV复制能力及致病力的影响,本研究利用H3N2 CIV的8质粒操作系统,拯救了三株重组H3N2 CIV毒株:PA-X基因表达大小为232个氨基酸多肽的亲本病毒CIV_PA-X_232;对PA编码区第191、192位氨基酸的密码子进行改造,PA-X基因不表达蛋白的重组病毒CIV_PA-X_Knock;对PA+1编码区第232位氨基酸进行突变,PA-X基因表达大小为252个氨基酸多肽的重组病毒CIV_PA-X_252。通过比较3株重组病毒的聚合酶活性,在MDCK细胞中的复制效率及对小鼠致病性的差异,来评价表达不同长度的PA-X基因对H3N2 CIV的影响。结果显示,CIV_PA-X_252和CIV_PA-X_Knock的聚合酶活性显著(P<0.05)高于CIV_PA-X_232,且CIV_PA-X_... 相似文献
77.
78.
Arunee THANASARASAKULPONG Pichayanut POOLPERM Pallop TANKAEW Takuo SAWADA Nattawooti STHITMATEE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(3):321-326
Recombinant outer membrane protein H (rOmpH) is a potential fowl cholera vaccine
candidate. The present study was aimed at developing rOmpH formulations for intranasal
administration. The rOmpH was purified and formulated with either Escherichia
coli enterotoxin B (LTB) or CpG oligodeoxynucleotides (ODN) as an adjuvant.
Antibody responses in chickens intranasally immunized with rOmpH in combination with 2
different adjuvants were significantly increased (P<0.05) post
immunization. Chicken survival rates showed that rOmpH formulated with ODN and LTB
elicited 90% and 70% protection, respectively. Our findings indicated that rOmpH
formulated with ODN elicited protection better than that formulated with LTB. Therefore,
the vaccines formulations in the present study can be considered new intranasal vaccine
formulations for fowl cholera in chickens. 相似文献
79.
在催化剂过氧磷钨酸十二烷基吡啶盐(Cat-PW4)的作用下,α-蒎烯与H2O2反应生成主要产物(3R,4R)-4,7,7-三甲基-6-氧杂二环[3.2.1]辛烷-3,4-二醇。不同反应条件对反应转化率和选择性的实验结果表明,最佳反应条件为:12.8 mmolα-蒎烯、5 m L溶剂三氯甲烷、0.2 g催化剂、3.3 m L 30%H2O2,反应温度40℃,反应时间3 h,α-蒎烯转化率和产物的选择性分别为94.7%和39.8%。反应结束后,该产物存在于水相和有机相中,通过萃取和重结晶分离提纯,得率11%,纯度达到98%;其分子结构通过红外光谱、紫外光谱、1H核磁共振谱、13C核磁共振谱、低分辨率质谱及高分辨率质谱确证。 相似文献
80.
通过用不同浓度的烟酰胺腺嘌呤二核苷酸磷酸(nicotinamide adenine dinucleotide phosphate, NADPH)合成酶抑制剂碘二苯(diphenylene iodonium, DPI)及过氧化氢(hydrogen peroxide, H2O2)清除剂二甲基硫脲(dimethylthiourea, DMTU)分别培养水稻(Oryza sativa L.)种子,研究内源H2O2对种子萌发过程胚根、胚芽和胚根根尖活力等的影响。结果表明,DPI及DMTU培养的水稻种子其胚根生长和胚芽生长均受到抑制,尤其是DPI对胚根生长的抑制作用更为显著。DPI和DMTU对水稻种子萌发的影响均呈现出浓度效应,即浓度越高,抑制作用越强。其中,DPI对水稻种子萌发的抑制作用比DMTU的更为明显。此外,胚根根尖的超氧阴离子(superoxide anion, O 2-)和H2O2含量随DMTU浓度增大而减少,根尖细胞受损也越严重。由此推测,内源H2O2可能参与调控水稻种子萌发过程。 相似文献