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排序方式: 共有376条查询结果,搜索用时 432 毫秒
371.
372.
Begum NA Kinoshita K Kakazu N Muramatsu M Nagaoka H Shinkura R Biniszkiewicz D Boyer LA Jaenisch R Honjo T 《Science (New York, N.Y.)》2004,305(5687):1160-1163
Activation-induced cytidine deaminase (AID) is required for the DNA cleavage step in immunoglobulin class switch recombination (CSR). AID is proposed to deaminate cytosine to generate uracil (U) in either mRNA or DNA. In the second instance, DNA cleavage depends on uracil DNA glycosylase (UNG) for removal of U. Using phosphorylated histone gamma-H2AX focus formation as a marker of DNA cleavage, we found that the UNG inhibitor Ugi did not inhibit DNA cleavage in immunoglobulin heavy chain (IgH) locus during CSR, even though Ugi blocked UNG binding to DNA and strongly inhibited CSR. Strikingly, UNG mutants that had lost the capability of removing U rescued CSR in UNG-/- B cells. These results indicate that UNG is involved in the repair step of CSR yet by an unknown mechanism. The dispensability of U removal in the DNA cleavage step of CSR requires a reconsideration of the model of DNA deamination by AID. 相似文献
373.
Atsuo IIDA Hitoshi TAKEMAE Ronald TARIGAN Ryosuke KOBAYASHI Hirokazu KATO Hiroshi SHIMODA Tsutomu OMATSU Supratikno Chaerul BASRI Ni Luh Putu Ika MAYASARI Srihadi AGUNGPRIYONO Ken MAEDA Tetsuya MIZUTANI Eiichi HONDO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1068
Here, we performed next-generation sequencing (NGS) on six large flying foxes (Pteropus vampyrus) collected in Indonesia. Seventy-five virus species in the liver tissue of each specimen were listed. Viral homologous sequences in the bat genome were identified from the listed viruses. This finding provides collateral evidence of viral endogenization into the host genome. We found that two of the six specimens bore partial sequences that were homologous to the plant pathogens Geminiviridae and Luteoviridae. These sequences were absent in the P. vampyrus chromosomal sequences. Hence, plant viral homologous sequences were localized to the hepatocytes as extrachromosomal DNA fragments. Therefore, this suggests that the bat is a potential carrier or vector of plant viruses. The present investigation on wild animals offered novel perspectives on viral invasion, variation, and host interaction. 相似文献
374.
Fumika Nanto-Hara Haruhiko Ohtsu Makoto Yamazaki Tatsuya Hirakawa Kan Sato Hitoshi Murakami 《The Journal of Poultry Science》2021,58(3):154
The aim of this study was to evaluate the effects of dietary brown rice on the growth performance, systemic oxidative status, and splenic inflammatory responses of broiler chickens under both thermo-neutral and chronic heat stress conditions. Forty 12-day-old male broiler chickens (ROSS 308) were randomly assigned to two groups and fed either a control diet (corn-based) or a brown rice-based diet. After seven days (19 days old), both groups were randomly divided into two sub-groups (n=10), one of which was exposed to heat stress (33°C for 14 days), while the other was maintained at 24°C. Heat exposure reduced the body weight gain and feed intake (p<0.01) of both groups. In terms of oxidative plasma states, heat exposure reduced the glutathione peroxidase activity and increased the ceruloplasmin content, while the 2-thiobarbituric acid reactive substance and reduced glutathione levels were not affected adversely. Heat exposure activated the immune responses, as evidenced by increased plasma immunoglobin levels, and altered splenic immune-related gene expressions including heat shock proteins, toll-like receptor 4, and interleukin-12. Under both thermo-neutral and heat stress conditions, dietary brown rice improved the growth performance, decreased the immunoglobulin levels, and down-regulated the expression of splenic immune-related genes of broilers, although their systemic oxidative status was not affected. Dietary brown rice should be considered as a valuable component of broiler chicken feeds subjected to both thermo-neutral and heat stress conditions. The positive effects of brown rice on bird performance may be associated with the modulation of the immune responses, as reflected by the decreased production of immunoglobulins and altered splenic immune-related gene expression. 相似文献
375.
Takayuki Takebe Takeo Kurihara Nobuaki Suzuki Kentaro Ide Hideki Nikaido Yosuke Tanaka Satoshi Shiozawa Hitoshi Imaizumi Shukei Masuma Yoshitaka Sakakura 《Fisheries Science》2012,78(2):343-350
We conducted a rearing experiment on Pacific bluefin tuna (PBT) larvae, which originated from one female broodstock, and determined
the growth history of the larvae to clarify when the growth difference occurs. We investigated the otolith microstructure
of the PBT larvae to examine the individual growth history and to predict the age and body size at the onset of individual
growth difference. Since total length (TL) of fish can be back-calculated from otolith radius, we back-calculated TLs of 100
fish of 19 days post hatch (dph) divided into three size groups (small, intermediate, large). Growth difference was recognized
from 3 dph (mouth opening), and the difference became larger thereafter. Growth of large-size fish was assumed to be promoted
by the feeding conditions of PBT larvae. 相似文献
376.
Phylogenetic analyses of plant-growth-promoting rhizobacteria isolated from tomato,lettuce, and Japanese pepper plants in Hyogo Prefecture,Japan 总被引:1,自引:0,他引:1
Tomohiro Kumatani Yukihiko Yoshimi Hitoshi Nakayashiki Masataka Aino 《Journal of General Plant Pathology》2009,75(4):316-321
Approximately 30,000 fluorescent bacterial strains isolated from tomato, lettuce, eggplant, Chinese cabbage, and Japanese
pepper plants at seven different locations in Hyogo Prefecture, were screened for plant-growth-promoting (PGP) activity to
induce disease resistance against bacterial wilt in tomato. The 37 strains that had higher PGP activity were subjected to
molecular phylogenetic analyses using the sequences of the 16S rRNA, gyrB and rpoD genes. Most of the strains were identified as Pseudomonas fluorescens or its close relative, P. putida, while a few strains were grouped with more distantly related bacterial species such as Enterobacter and Stenotrophomonas. The phylogenetic relationships among tomato and lettuce isolates mostly coincided with the source locality and host plants,
with a few exceptions. In contrast, isolates from Japanese pepper plants did not form their own cluster but represented several
different bacterial species. 相似文献