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91.
Hiromichi MITAKE Naoto ITO Kota OKADERA Kazuma OKADA Kento NAKAGAWA Tomomi TANAKA Kiyohito KATSURAGI Kasumi KASAHARA Toshihide NIHONGI Hiroshi TSUNEMITSU Makoto SUGIYAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(2):221-224
A total of 568 normal feces from calves on a beef farm in Fukui Prefecture, Japan, in 2011–2012 were examined by RT-semi-nested PCR for rotavirus A (RVA) VP4 genes. Through partial sequencing and BLAST analyses of 84 VP4-positive specimens, we identified an avian-like RVA strain, N2342, which shares highest nucleotide identity (80.0%) with known avian-like bovine strain 993/83, in one specimen. Phylogenetic analysis also revealed a close genetic relationship between N2342 and avian RVAs, suggesting bird-to-cattle transmission. We observed frequent contact of wild birds with calves in the farm, suggesting that these birds were the source of the virus. 相似文献
92.
Takashi TANAKA Mito KANATSU-SHINOHARA Michiko HIROSE Atsuo OGURA Takashi SHINOHARA 《The Journal of reproduction and development》2015,61(5):473-484
Diploid germ cells are thought to have pluripotency potential. We recently described a method to derive pluripotent stem cells (PSCs) from cultured spermatogonial stem cells (SSCs) by depleting Trp53 and Dmrt1, both of which are known suppressors of teratomas. In this study, we used this technique to analyze the effect of this protocol in deriving PSCs from the male germline at different developmental stages. We collected primordial germ cells (PGCs), gonocytes and spermatogonia, and the cells were transduced with lentiviruses expressing short hairpin RNA against Dmrt1 and/or Trp53. We found that PGCs are highly susceptible to reprogramming induction and that only Trp53 depletion was sufficient to induce pluripotency. In contrast, gonocytes and spermatogonia were resistant to reprogramming by double knockdown of Dmrt1 and Trp53. PSCs derived from PGCs
contributed to chimeras produced by blastocyst injection, but some of the embryos showed placenta-only phenotypes suggestive of epigenetic abnormalities of PGC-derived PSCs. These results show that PGCs and gonocytes/spermatogonia have distinct reprogramming potential and also suggest that fresh and cultured SSCs do not necessarily have the same properties. 相似文献
93.
Takuya HIROSE Takayuki OGURA Keisuke TANAKA Jun MINAGUCHI Takeshi YAMAUCHI Toshiyuki FUKADA Yoh-ichi KOYAMA Kazushige TAKEHANA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1385-1389
Ehlers-Danlos syndrome (EDS) is a group of disorders caused by abnormalities that are
identified in the extracellular matrix. Transforming growth factor-β1 (TGF-β1) plays a
crucial role in formation of the extracellular matrix. It has been reported that the loss
of function of zinc transporter ZRT/IRT-like protein 13 (ZIP13) causes the spondylocheiro
dysplastic form of EDS (SCD-EDS: OMIM 612350), in which dysregulation of the TGF-β1
signaling pathway is observed, although the relationship between the dermis abnormalities
and peripheral TGF-β1 level has been unclear. We investigated the characteristics of the
dermis of the Zip13-knockout (KO) mouse, an animal model for SCD-EDS.
Both the ratio of dermatan sulfate (DS) in glycosaminoglycan (GAG) components and the
amount of collagen were decreased, and there were very few collagen fibrils with diameters
of more than 150 nm in Zip13-KO mice dermis. We also found that the
TGF-β1 level was significantly higher in Zip13-KO mice serum. These
results suggest that collagen synthesis and collagen fibril fusion might be impaired in
Zip13-KO mice and that the possible decrease of decorin level by
reduction of the DS ratio probably caused an increase of free TGF-β1 in
Zip13-KO mice. In conclusion, skin fragility due to defective
ZIP13 protein may be attributable to impaired extracellular matrix
synthesis accompanied by abnormal peripheral TGF-β homeostasis. 相似文献
94.
Kazuhiro UMEYAMA Kasumi HONDA Hitomi MATSUNARI Kazuaki NAKANO Tatsuro HIDAKA Keito SEKIGUCHI Hironori MOCHIZUKI Yasuhiro TAKEUCHI Tsukasa FUJIWARA Masahito WATANABE Masaki NAGAYA Hiroshi NAGASHIMA 《The Journal of reproduction and development》2013,59(6):599-603
Somatic cell nuclear transfer (SCNT) is a useful technique for creating pig strains
that model human diseases. However, production of numerous cloned disease model pigs
by SCNT for large-scale experiments is impractical due to its complexity and
inefficiency. In the present study, we aimed to establish an efficient procedure for
proliferating the diabetes model pig carrying the mutant human hepatocyte nuclear
factor-1α gene. A founder diabetes transgenic cloned pig was generated by SCNT and
treated with insulin to allow for normal growth to maturity, at which point
epididymal sperm could be collected for cryopreservation. In vitro
fertilization and intrafallopian insemination using the cryopreserved epididymal
sperm resulted in diabetes model transgenic offspring. These results suggest that
artificial reproductive technology using cryopreserved epididymal sperm could be a
practical option for proliferation of genetically modified disease model pigs. 相似文献
95.
Natsumi ENDO Kiyosuke NAGAI Tomomi TANAKA Hideo KAMOMAE 《The Journal of reproduction and development》2013,59(3):282-287
The aim of this study was to examine whether increased frequency of luteinizing hormone
(LH) pulses influences luteal progesterone (P4) secretion by measuring
progesterone concentrations at the secreted (caudal vena cava) and circulating levels
(jugular vein) in lactating dairy cows. Cows received six intravenous administrations of
2.5 μg of GnRH (gonadorelin acetate, n=4) or 2 ml saline (n=3) at 1-h intervals on 12.4 ±
0.4 (mean ± SE) days after ovulation. Blood samples were collected from the caudal vena
cava and jugular vein every 12 min for 12 h (6 h before and after treatment). During the 6
h after treatment, frequency of LH pulses (5.3 ± 0.3 and 3.0 ± 0.0 pulses/6 h) and mean LH
concentration (0.50 ± 0.06 and 0.38 ± 0.05 ng/ml) were greater (P<0.05) in GnRH-treated
cows than in saline-treated cows. Mean P4 concentration and amplitude of
P4 pulses in the caudal vena cava during the 6 h after treatment were greater
(P<0.05) in GnRH-treated cows than in saline-treated cows, but the frequency of
P4 pulses was not different between the groups. Mean P4
concentration in the jugular vein during the 6 h after treatment was also higher
(P<0.05) in GnRH-treated cows than in saline-treated cows (7.0 ± 1.3 and 5.4 ± 0.9
ng/ml). These results indicate that the increased frequency of LH pulses stimulates
progesterone secretion from the functional corpus luteum and brings about higher
P4 concentrations in the circulating blood in lactating dairy cows. 相似文献
96.
97.
Natsumi ENDO Kiyosuke NAGAI Tomomi TANAKA Hideo KAMOMAE 《The Journal of reproduction and development》2013,59(2):107-114
The present study was designed to assess progesterone profiles at the secreted (caudal
vena cava) and circulating levels (jugular vein) and luteinizing hormone (LH) secretion
pattern in lactating and non-lactating cows with reference to feeding. Four lactating and
four non-lactating cycling Holstein cows were examined. Blood samples were collected
simultaneously from the caudal vena cava (via a catheter inserted from the coccygeal vein)
and the jugular vein every 15 min for 12 h (0500–1700 h) during the functional luteal
phase. Cows were fed 50% of the daily diet 6 h after the start of blood sampling. During
the 12-h sampling period, mean progesterone concentrations in the caudal vena cava did not
differ between lactating and non-lactating cows (49.0 ± 2.9 and 53.3 ± 3.7 ng/ml; mean ±
SE), whereas mean progesterone concentrations in the jugular vein in lactating cows were
higher than those in non-lactating cows (6.4 ± 0.1 and 5.6 ± 0.1 ng/ml, P < 0.001).
Lactating cows had a higher frequency of LH pulses than non-lactating cows (7.0 ± 0.7 and
4.3 ± 0.9 pulses/12 h, P<0.05). The influence of feeding was not observed on LH
profiles but was observed on progesterone profiles in both veins. Progesterone
concentrations in the caudal vena cava increased after feeding in both groups.
Progesterone concentrations in the jugular vein decreased after feeding in lactating cows
but not in non-lactating cows. These results indicate the difference in feeding-related
changes in progesterone dynamics between lactating and non-lactating cows. 相似文献
98.
Tomomi TANAKA Satoshi OHKURA Yoshihiro WAKABAYASHI Takenobu KUROIWA Kiyosuke NAGAI Natsumi ENDO Akira TANAKA Hisanori MATSUI Masami KUSAKA Hiroaki OKAMURA 《The Journal of reproduction and development》2013,59(6):563-568
The aim of the present study was to determine if the estradiol-induced luteinizing
hormone (LH) surge is influenced by the constant exposure to TAK-683, an
investigational metastin/kisspeptin analog, that had been established to depress the
pulsatile gonadotropin-releasing hormone (GnRH) and LH secretion in goats.
Ovariectomized goats subcutaneously received TAK-683 (TAK-683 group, n=6) or vehicle
(control group, n=6) constantly via subcutaneous implantation of an osmotic pump.
Five days after the start of the treatment, estradiol was infused intravenously in
both groups to evaluate the effects on the LH surge. Blood samples were collected at
6-min intervals for 4 h prior to the initiation of either the TAK-683 treatment or
the estradiol infusion, to determine the profiles of pulsatile LH secretion. They
were also collected at 2-h intervals from –4 h to 32 h after the start of estradiol
infusion for analysis of LH surges. The frequency and mean concentrations of LH
pulses in the TAK-683 group were remarkably suppressed 5 days after the start of
TAK-683 treatment compared with those of the control group (P<0.05). On the other
hand, a clear LH surge was observed in all animals of both groups. There were no
significant differences in the LH concentrations for surge peak and the peak time of
the LH surge between the TAK-683 and control groups. These findings suggest that the
effects of continuous exposure to kisspeptin or its analog on the mechanism(s) that
regulates the pulsatile and surge mode secretion of GnRH/LH are different in
goats. 相似文献
99.
Overexpression of the LASAP2 gene for secretory acid phosphatase in white lupin improves the phosphorus uptake and growth of tobacco plants 总被引:1,自引:0,他引:1
Jun WASAKI Hayato MARUYAMA Miho TANAKA Takuya YAMAMURA Hiraki DATEKI Takuro SHINANO Susumu ITO Mitsuru OSAKI 《Soil Science and Plant Nutrition》2009,55(1):107-113
Secretion of acid phosphatase (APase) from the roots to take up phosphorus (P) is a well-known strategy of plants under P-deficient conditions. White lupin, which shows vigorous growth in low-P soils, is noted for its ability to secrete APase under P-deficient conditions. The APase secreted by white lupin roots is stable in soil solution and shows low substrate specificity, suggesting that genetic modification of plants using the APase gene LASAP2 might improve their ability to use organic P. The objective of the present study was to evaluate the potential of LASAP2 transgenic plants to increase organic P utilization. Dry matter production and P accumulation were higher in LASAP2 transgenic tobacco plants grown in gel media containing soluble phytate as the sole P source than in wild-type tobacco plants. Phosphorus uptake by the transgenic plants also increased in soil culture conditions. LASAP2 was apparently more effective in the liberation of organic P, including phytate, in the soil than the native tobacco APase. Thus, the enzymatic stability of LASAP2 in the soil appears to be an important factor for P acquisition. 相似文献
100.
Venecio U. ULTRA Jr Atsushi NAKAYAMA Sota TANAKA Yumei KANG Katsutoshi SAKURAI Kz IWASAKI 《Soil Science and Plant Nutrition》2009,55(1):160-169
A pot culture experiment was conducted to investigate the effects of amorphous iron-(hydr)oxide (Am-FeOH) amendments on arsenic (As) availability and its uptake by rice ( Oryza sativa L. cv. BR28) irrigated with As-contaminated water. A rhizobag system was established using 3.5 L plastic pots, each containing one central compartment for plant growth, a middle compartment and an outside compartment. Three levels of laboratory-synthesized Am-FeOH (0, 0.1 and 0.5% w/w) were used to amend samples of the As-free sandy loam paddy soil placed into each compartment of the rhizobag system. The soils were submerged with a solution containing 5 mg L−1 As(V). Two-week-old rice seedlings were planted in the central compartments and cultured for 9 weeks under greenhouse conditions. The addition of 0.1% Am-FeOH to the soil irrigated with As-contaminated water improved plant growth, reduced the As concentration in the plants and enhanced Fe-plaque formation on the root surfaces. Analysis of soil solution samples collected during the experiment revealed higher pH levels and lower redox potentials in the soils amended with Am-FeOH at the onset of soil submergence, but later the soil solution collected from the 0.1% Am-FeOH treatment was slightly acidic and more oxidized than the solution from the 0% treatment. This indicated active functioning of the roots in the soil treated with 0.1% Am-FeOH. The concentrations of As(III) in the soil solution collected from the central compartment were significantly reduced by the Am-FeOH amendments, whereas in the soil treated with 0% Fe, As(III) accumulated in the rhizosphere, particularly during the late-cultivation period. The improvement in plant growth and reduction in As uptake by plants growing in the Am-FeOH treated soil could be attributed to the reduction of available As in the soil solution, mainly as a result of the binding of As to the Fe-plaque on the root surfaces. 相似文献