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201.
Hossam EL-SHEIKH ALI Go KITAHARA Youji TAMURA Ikuo KOBAYASHI Koichiro HEMMI Shidow TORISU Hiroshi SAMESHIMA Yoichiro HORII Samy ZAABEL Shunichi KAMIMURA 《The Journal of reproduction and development》2013,59(1):59-65
The aim of the present study was to describe the temperature of the different portions
of the female genital tract and their relation to rectal temperature and to investigate
the effect of steroid hormones profiles on these variables over the estrous cycle in
cattle. Four nonpregnant Japanese Black cows were investigated daily over two successive
estrous cycles using a digital thermometer with a long probe and rounded-end sensor to
record the temperature of the rectum (RT), vagina (VT), cervix (CT), uterine body (UBT)
and uterine horns (UHT). Blood samples were collected immediately before temperature
recording to assay peripheral levels of progesterone (P4) and estradiol-17β
(E2). Moreover, transrectal ultrasonography was carried out after temperature
recording to monitor the ovulatory follicle and track ovulation. During the experiment,
the ambient temperature and relative humidity were recorded for further calculation of the
temperature humidity index (THI). The temperature within the genital tracts in these cows
progressively increased towards the uterine horns from the vagina. The VT, CT, UBT and
UHTs were significantly higher in association with peripheral P4 concentrations
greater than 4 ng/ml (mid-luteal phase) when compared with lower peripheral P4
concentrations. The VT was more significantly (P<0.01) correlated to the CT, UBT and
UHTs than RT. In conclusion, a temperature gradient was present among the vagina, cervix
and uterus over the estrous cycle, and changes in peripheral P4 concentrations
were associated with the thermal variations within these portions. The VT could be more
beneficial than RT in monitoring temperature of deeper portions of the female genital
tract in bovine. 相似文献
202.
203.
Bhuwan Rai Hiroko Takahashi Kenji Kato Yo-ichiro Sato Ikuo Nakamura 《Genetic Resources and Crop Evolution》2012,59(8):1713-1726
PolA1, a single-copy nuclear gene encoding the largest subunit of RNA polymerase I, comprises highly polymorphic intron 19 and nucleotide tag (Ntag) sequences. We analyzed these sequences in 42 accessions, which differed in ploidy, of Triticum–Aegilops and Hordeum species. The lengths of the intron 19 sequences were ca. 110?bp long in Triticum–Aegilops species, except in four Sitopsis species, Ae. longissima, Ae. searsii, Ae. sharonensis, Ae. speltoides, which had introns similar in length to those of Hordeum species, i.e., ca. 240?bp long. Phylogenetic analyses of the Ntag sequences showed that the four Sitopsis and remaining Triticum–Aegilops species were classified into two discrete Hordeum and Triticum clades, respectively. The A and D genome-specific Ntag sequences of polyploid wheats were highly homologous with those of T. urartu and Ae. tauschii, respectively. In Ae. bicornis, another Sitopsis species, two accessions had the short intron 19 and Triticum–type Ntag sequence, which were highly homologous with those of the B genome in polyploid wheats, whereas one accession contained the long intron 19 and Hordeum–type Ntag sequences. In contrast, partial sequence analyses revealed that the three accessions of Ae. bicornis shared highly homology to single-copy DMC1 and EF-G genes. The discrepancy between these results indicates that the Sitopsis species were probably established by hybrid speciation including ancient introgressive hybridization between progenitors of Triticum–Aegilops and Hordeum. Although many researchers have proposed Ae. speltoides as a candidate for the B genome donor, our data suggest the existence of diploid B genome species in the past that were responsible for the origin of both polyploid wheats and Sitopsis species, including Ae. speltoides. 相似文献
204.
该文应用年轮气候学理论和方法对毛乌素沙地小叶杨和北京杨年轮结构的变化特征及其与月平均气温和月降水量的响应关系进行了分析.结果表明,小叶杨和北京杨的年轮宽度指数序列的变动模式很相似,但小叶杨年轮宽度指数的变动幅度比北京杨大得多,这与毛乌素沙地的气候变化大的特点相一致.用月平均气温和月降水量作为气候因子建立的响应函数模型,能够说明2种杨树年轮宽度和导管腔径变化的46%~55%.小叶杨的年轮宽度和导管腔径对月平均气温及月降水量的反应基本上是一致的.当年2月气温过高会抑制小叶杨年轮宽度和导管腔径的增加,而夏季降水量和气温对其年轮宽度和导管腔径增大有明显的促进作用.北京杨的年轮宽度和导管腔径对月平均气温及月降水量的反应不一致,并且对气候因子的响应关系不明显. 相似文献
205.
Ikuo?YoshinagaEmail author Yanwen?Feng Ram?Karan?Singh Eisaku?Shiratani 《Paddy and Water Environment》2004,2(3):145-152
Based on an experimental field study in Japan, a model was developed to simulate dissolved nitrogen in water ponded in a paddy field. As input data, the model uses meteorological data, water balance in the field, nitrogen concentration in inlet water, and the nitrogen contribution of applied fertilizer. Five model parameters need calibration. A practical application of the model is the simulation of NH4-N and NO2+3-N concentrations in water ponded in a paddy field. The model improves our understanding of the interactions between forms of dissolved nitrogen in ponded water and can explain the complex changes in dissolved nitrogen concentrations in water ponded on a paddy field. 相似文献
206.
Rika Nakamura Ivane R. Pedrosa‐Gerasmio Rod Russel R. Alenton Reiko Nozaki Hidehiro Kondo Ikuo Hirono 《Journal of fish diseases》2019,42(8):1125-1132
Acute hepatopancreatic necrosis disease (AHPND), caused by a toxin‐producing Vibrio parahaemolyticus strain, has become a serious threat to shrimp aquaculture. The need to regulate antibiotic use prompted the development of alternative ways to treat infections in aquaculture including the use of chicken egg yolk immunoglobulin (IgY) for passive immunization. This study evaluated the protective effect of IgY against AHPND infection in Litopenaeus vannamei (Boone). IgY was isolated from eggs laid by hens immunized with recombinant PirA‐like (rPirA) and PirB‐like (rPirB) toxins. Whole‐egg powders having IgY specific to rPirA (anti‐PirA‐IgY) and rPirB (anti‐PirB‐IgY) and IgY from non‐immunized hen (control‐IgY) were mixed with basal diets at 20% concentrations and used to prefeed shrimp 3 days before the bacterial challenge test. Survival rates of the challenged shrimp fed the anti‐PirA‐IgY, anti‐PirB‐IgY and control‐IgY diets were 86%, 14% and 0%, respectively. Only the feed containing anti‐PirA‐IgY protected shrimp against AHPND. Increasing the concentration of rPirA antigen to immunize hens and lowering the amount of egg powder in feeds to 10% consistently showed higher survival rates in shrimp fed with anti‐PirA‐IgY (87%) compared with the control (12%). These results confirm that addition of anti‐PirA‐IgY in feeds could be an effective prophylactic method against AHPND infection in shrimp. 相似文献
207.
Toshihiro Wada Kyoichi Kamiyama Shinya Shimamura Ikuo Matsumoto Takuji Mizuno Yoshiharu Nemoto 《Fisheries Science》2011,77(5):785-793
Habitat utilization, feeding, and growth of a rare pleuronectid flatfish, spotted halibut Verasper variegatus, were examined in a brackish lagoon in northeastern Japan: Matsukawa-ura. The distribution and date–length data of spotted
halibut collected mainly from beam-trawl samplings during 1983–2008 indicated that age-0 juveniles [n = 25, 6.0–18.0 cm total length (TL)] and older spotted halibut (n = 71, 13.8–43.0 cm TL) inhabited almost the entire northern part of Matsukawa-ura. Comparative distribution surveys of spotted
halibut, stone flounder, and marbled flounder during 1985–1989 revealed similar distribution patterns of these flatfishes;
the highest densities were found around the central part of Matsukawa-ura, although significantly lower abundance was detected
for spotted halibut. Linear growth equations of age-0 juveniles demonstrated that spotted halibut were able to achieve high
growth after June, probably because abundant prey (e.g., mysids and gammarids) and suitable physical conditions (warmer water
temperature and lower salinity) were present. The main prey items shifted from various crustaceans including mysids, caridean
shrimps, and anomurans to brachyura Hemigrapsus spp. (≥20 cm TL). Our study shows that spotted halibut use the shallow brackish lagoon as an important nursery for juveniles,
and also as a feeding ground for young and adults. 相似文献
208.
209.
Threechada Danwattananusorn Fernand F. Fagutao Aiko Shitara Hidehiro Kondo Takashi Aoki Reiko Nozaki Ikuo Hirono 《Fisheries Science》2011,77(6):929-937
Heat shock proteins (HSPs) are proteins that are expressed more strongly when the cells are exposed to physiological and stressful
conditions. In this study, the full-length cDNAs of heat shock proteins 40 (MjHSP40), 70 (MjHSP70) and 90 (MjHSP90) were cloned from kuruma shrimp Marsupenaeus japonicus. The open reading frames (ORFs) of the cDNA clones have lengths of 1,191, 1,959 and 2,172 bp and encode 396, 652 and 723
amino acid residues, respectively. The predicted MjHSP40 amino acid sequence contains a J domain, a glycine/phenylalanine-rich region, and a central domain containing four repeats
of a CxxCxGxG motif, indicating that it is a type I HSP40 homolog. The signature sequences of the HSP70 and HSP90 gene families
are conserved in the MjHSP70 and MjHSP90 amino acid sequences. The deduced amino acid sequences of MjHSP70 and MjHSP90 share high identity with previously reported shrimp HSP70s and HSP90s, respectively. The expression of MjHSP90 mRNA increased at 32°C. Additionally, the expressions of MjHSP40, MjHSP70 and MjHSP90 mRNAs increased in defense-related tissues (i.e., hemocytes and lymphoid organ) when the shrimp were challenged with
white spot syndrome virus. 相似文献
210.
This study describes the effect of starch properties of Japanese wheat flours on the quality of white salted noodles (WSN). Starch was isolated from 24 flours of 17 Japanese cultivars and amylose content was determined along with pasting properties by Rapid Visco Analyser (RVA), thermal properties by differential scanning calorimetry (DSC), and the distribution of amylopectin chain length by high‐performance anion exchange chromatography (HPAEC). Twenty flours were used to prepare WSN. As expected, 5–6% lower amylose content was associated with good WSN quality (higher scores in softness, elasticity, and smoothness). RVA analysis indicated that the pasting temperature had the greatest influence on WSN quality, while breakdown and setback showed slight effects on WSN quality. DSC results showed that lower endothermal enthalpy (ΔH) in the amylose‐lipid complex was associated with good WSN quality. Chainlength distribution of amylopectin by HPAEC was not an important factor in relation to WSN quality. 相似文献