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141.
142.
Chiral high-performance liquid chromatography (HPLC) separation of lignans with semi-micro columns of 1.0–2.0mm inner diameter (i.d.) was established for the first time. Practical sensitivity was increased 5 to 20-fold compared with that of conventional chiral HPLC using analytical columns with 4.6mm i.d. The semi-micro chiral HPLC system can be applied to high-sensitivity enantiomeric separation of many chiral organic compounds in addition to lignans. 相似文献
143.
Shoji Noguchi Abdul Rahim Nik Zulkifli Yusop Makoto Tani Toshiaki Sammori 《Journal of Forest Research》1997,2(3):125-132
Field observations were conducted at Bukit Tarek Experimental Watershed in Peninsular Malaysia to investigate the relationship
between rainfall-runoff responses and variation in soil moisture in a tropical rain forest. Stormflow depended strongly on
the antecedent wetness as represented by the initial runoff rate. Though heavy rains fell in almost every month, the soil
moisture decreased when fair weather was sustained. The soil moisture depleted and became dry at 160 cm depth during occasional
dry spells. During dry conditions, streamflow responded quickly to rain events but declined rapidly after the rain stopped,
and the soil moisture of surface soil (≤20 cm) increased but remained dry at lower depths (≽80 cm). This suggests that the
rain water was mostly retained in the soil and only small proportions appeared as stormflow. As soil moisture conditions became
wetter, the recession limb of the storm hydrograph was more gradual. Stormflow volume increased with increasing soil moisture.
During wet conditions, the soil profile was moist at all parts of the slope. The hydraulic gradient was around 1.0 and there
was downward soil water flux, which followed the pressure gradient. This suggests that subsurface flow from the upper part
of the slope might also be important for stream-flow production. Positive pressures were observed at 10 cm and 160 cm depths
during large storms. The behavior of the subsurface flow might be an important determinant of stormflow. 相似文献
144.
Takumi MOTOYA Noriko NAGATA Harumi KOMORI Ikuko DOI Miho KUROSAWA Toshimasa KETA Nobuya SASAKI Koji ISHII 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1705-1709
Hepatitis E virus (HEV) is known as a causative agent of zoonosis and food poisoning.
Pigs and some species of wild animals, including wild boar, are known to be a reservoir of
HEV. In this study, we investigated the situation regarding HEV infection in wild boars in
Ibaraki Prefecture, Japan. Serum, liver and feces samples from 68 animals were collected,
and the presence or absence of HEV genomic RNA and HEV antibodies were analyzed. The viral
genome was detected in samples from 7 (10.3%) animals, with all HEVs classified as
genotype 3, subtype 3b. HEV antibodies were detected in samples from 28 (41%) animals.
This report demonstrates for the first time the high prevalence of HEV infection in wild
boars in Ibaraki Prefecture. 相似文献
145.
146.
In this study, the formation of complexes between surfactants and the helical chains of amylopectins was confirmed. Nonionic surfactants with hydrophobic and hydrophilic groups of appropriate size and chemical structure enhanced the swelling and gelatinization processes of starch granules. Hydrophobic groups form complexes with the amylose and linear chains of amylopectin by becoming inserted into the hydrophobic inner area of the helical structures. The hydrophilic groups help the approach of the hydrophobic groups into the hydrated molecular chains and thus aid the formation of the complex. Among the anionic surfactants tested, SDS and sodium n‐decyl benzenesulfate caused maximum swelling and gelatinization peaks. The average length of the amylopectin exterior chains is almost the same as that of the hydrophobic chains of SDS (16.9 Å) and of sodium decyl benzenesulfate (18.2 Å). This suggests that these anionic surfactants form rigid complexes with the exterior of the amylopectin by fitting their hydrophobic chains to the hydrophobic inside of the helical structures of these short exterior chains. This process was clarified by NMR analysis and by a decrease in the complex with the addition of iodine. The hydrophobic alkyl chains of anionic and cationic surfactants fix to the edge of the starch molecular chains by forming inclusion complexes with the helical chains of the amylopectin. Cationic ions interact with the starch molecular chains, causing a negative charge that results in a more rapid and efficient swelling of the starch granules. A decrease in setback value occurs due to the inhibition of rearrangement among the starch molecular chains. With SDS, the complex molecular chains become more extensively developed through the repulsion effects of the anionic ions resulting in a larger swelling power and gelatinization peak. 相似文献
147.
Tamer Fawzy Ismail Akira Takeshita Naoko Umeda Toshiaki Itami Terutoyo Yoshida 《Fisheries Science》2011,77(1):113-118
This study determined the minimum inhibitory concentrations (MICs) for oxytetracycline hydrochloride (OTC) and erythromycin
(Em), along with the α-glucosidase (α-glu) activities in 110 Nocardia
seriolae strains isolated in Miyazaki and Kagoshima prefectures in 2008–2009. The strains were examined for the presence of the tet(K), tet(L), tet(M), tet(O), tet(S), erm(A), erm(B), mph(A), mef(A), and msr(D) genes. All the α-glu-positive strains (n = 15) were OTC resistant and Em sensitive, with MICs of 32–64 and <0.125 μg/ml, respectively. All the α-glu-negative strains
(n = 95) were OTC sensitive, with MICs of 2–4 μg/ml, and most of them (93 of 95) were Em resistant, with MICs of >128 μg/ml.
The MICs for Em in the remaining 2 α-glu-negative strains were <0.125 μg/ml. The 15 OTC-resistant strains possessed the tet(K) and/or tet(L) gene(s), and all of the 93 Em-resistant strains possessed both the mef(A) and msr(D) genes. The relationship between α-glu activity and drug sensitivity of the N. seriolae strains may explain the difference in prevalence of each phenotype. Nevertheless, the relationship should be further explored
using N. seriolae isolates collected from more prefectures and farms. 相似文献
148.
The mechanisms by which nonnative species establish populations can be classified into two broad categories: they usurp the
niches of native species through interspecific competition, or they avoid this intense interspecific competition by making
use of minimal niche overlap with the native species. In this study, we considered how a nonnative salmonid species, the rainbow
trout Oncorhynchus mykiss, established a population in the presence of the native salmonid species, the masu salmon O. masou, in Hokkaido, Japan. Circumstantial field evidence shows that the masu salmon exceeds the rainbow trout in abundance and
suggests that these species use different types of cover habitat (rainbow trout abundance increases with increasing abundance
of large woody debris aggregates, whereas masu salmon abundance increases with increasing abundance of undercut banks). These
results imply that the rainbow trout established a population due to minimal niche overlap with the masu salmon, and not by
competitive exclusion of the native species. 相似文献
149.
A possible function of Nik-related kinase in the labyrinth layer of delayed delivery mouse placentas
Hiroshi YOMOGITA Hikaru ITO Kento HASHIMOTO Akihiko KUDO Toshiaki FUKUSHIMA Tsutomu ENDO Yoshikazu HIRATE Yoshihiro AKIMOTO Masayuki KOMADA Yoshiakira KANAI Naoyuki MIYASAKA Masami KANAI-AZUMA 《The Journal of reproduction and development》2023,69(1):32
In mice and humans, Nik-related protein kinase (Nrk) is an X-linked gene that encodes a serine/threonine kinase belonging to GCK group 4. Nrk knockout (Nrk KO) mice exhibit delayed delivery, possibly due to defective communication between the Nrk KO conceptus and its mother. However, the mechanism of delayed labor remains largely unknown. Here, we found that in pregnant mothers with the Nrk KO conceptus, the serum progesterone (P4) and placental lactogen (PL-2) concentrations in late pregnancy were higher than those in the wild type. Moreover, we demonstrated that Nrk is expressed in trophoblast giant cells (TGCs) and syncytiotrophoblast-2 (SynT-2) in the labyrinth layer of the mouse placenta. In the human placenta, NRK is also expressed in Syn-T in villi. Both human Syn-T and mouse TGCs of the labyrinth layer are present within fetal tissues that are in direct contact with the maternal blood. The labyrinth layer of the Nrk KO conceptus was gigantic, with enlarged cytoplasm and Golgi bodies in the TGCs. To investigate the function of Nrk in the labyrinth layer, a differentially expressed gene (DEG) analysis was performed. The DEG analysis revealed that labor-promoting factors, such as prostaglandins, were decreased, and pregnancy-maintaining factors, such as the prolactin family and P4 receptor, were increased. These findings suggest that the Nrk KO mice exhibit delayed delivery owing to high P4 concentrations caused by the hypersecretion of pregnancy-maintaining factors, such as PL-2, from the placenta. 相似文献
150.
Masayuki YOKOZAWA Yasuhito SHIRATO Toshihiro SAKAMOTO Seiichirou YONEMURA Makoto NAKAI Toshiaki OHKURA 《Soil Science and Plant Nutrition》2010,56(1):168-176
We estimated the carbon (C) sequestration potential of organic matter application in Japanese arable soils at a country scale by applying the Rothamsted carbon (RothC) model at a 1-km resolution. After establishing the baseline soil organic carbon (SOC) content for 1990, a 25-year simulation was run for four management scenarios: A (minimum organic matter application), B (farmyard manure application), C (double cropping for paddy fields) and D (both B and C). The total SOC decreased during the simulation in all four scenarios because the C input in all four scenarios was lower than that required to maintain the baseline 1990 SOC level. Scenario A resulted in the greatest depletion, reflecting the effects of increased organic matter application in the other scenarios. The 25-year difference in SOC accumulation between scenario A and scenarios B, C and D was 32.3, 11.1 and 43.4 Mt C, respectively. The annual SOC accumulation per unit area was similar to a previous estimate, and the 25-year averages were 0.30, 0.10 and 0.41 t C ha−1 year−1 for scenarios B, C and D, respectively. The system we developed in the present study, that is, linking the RothC model and soil spatial data, can be useful for estimating the potential C sequestration resulting from an increase in organic matter input to Japanese arable soils, although more feasible scenarios need to be developed to enable more realistic estimation. 相似文献