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81.
Satomi ISHII Nobuo SUZUI Sayuri ITO Noriko S. ISHIOKA Naoki KAWACHI Norikuni OHTAKE Takuji OHYAMA Shu FUJIMAKI 《Soil Science and Plant Nutrition》2009,55(5):660-666
Real-time images of nitrogen fixation in an intact nodule of hydroponically cultured soybean ( Glycine max [L] Merr.) were obtained. In the present study, we developed a rapid method to produce and purify 13 N-labeled radioactive nitrogen gas (half life: 9.97 min). 13 N was produced from a 16 O (p, α) 13 N nuclear reaction. The target chamber was filled with CO2 and irradiated for 10 min with protons at an energy of 18.3 MeV and an electric current of 5 μA, which was delivered from a cyclotron. All CO2 in the collected gas was absorbed and removed with powdered soda-lime in a syringe and replaced with helium gas. The resulting gas was injected into gas chromatography and separated and a 35 mL fraction, including the peak of [13 N]-nitrogen gas, was collected by monitoring the chromatogram. The obtained gas was mixed with 10 mL of O2 and 5 mL of N2 and used in the tracer experiment. The tracer gas was fed into the underground part of intact nodulated soybean plants and serial images of the distribution of 13 N were obtained non-invasively using a positron-emitting tracer imaging system (PETIS). The rates of nitrogen fixation of the six test plants were estimated to be 0.17 ± 0.10 μmol N2 h−1 from the PETIS image data. The decreasing rates of assimilated nitrogen were also estimated to be 0.012 ± 0.011 μmol N2 h−1 . In conclusion, we successfully observed nitrogen fixation in soybean plants with nodules non-invasively and quantitatively using [13 N]N2 and PETIS. 相似文献
82.
83.
Erika HAYASHI Sayaka WAKAYAMA Daiyu ITO Ayumi HASEGAWA Keiji MOCHIDA Masatoshi OOGA Atsuo OGURA Teruhiko WAKAYAMA 《The Journal of reproduction and development》2022,68(2):118
Mammalian embryos are most commonly cryopreserved in liquid nitrogen; however, liquid nitrogen is not available in special environments, such as the International Space Station (ISS), and vitrified embryos must be stored at −80°C. Recently, the high osmolarity vitrification (HOV) method was developed to cryopreserve mouse 2-cell stage embryos at −80°C; however, the appropriate embryo is currently unknown. In this study, we compared the vitrification resistance of in vivo-derived, in vitro fertilization (IVF)-derived, and intracytoplasmic sperm injection (ICSI)-derived mouse 2-cell embryos against cryopreservation at −80°C. The ICSI embryos had lower survival rates after warming and significantly lower developmental rates than the in vivo and IVF embryos. Further, IVF embryos had a lower survival rate after warming, but a similar rate to the in vivo embryos to full-term development. This result was confirmed by simultaneous vitrification of in vivo and IVF embryos in the same cryotube using identifiable green fluorescent protein-expressing embryos. We also evaluated the collection timing of the in vivo embryos from the oviduct and found that late 2-cell embryos had higher survival and developmental rates to full-term than early 2-cell embryos. Some early 2-cell embryos remained in the S-phase, whereas most late 2-cell embryos were in the G2-phase, which may have affected the tolerance to embryo vitrification. In conclusion, when embryos must be cryopreserved under restricted conditions, such as the ISS, in vivo fertilized embryos collected at the late 2-cell stage without long culture should be employed. 相似文献
84.
KOJI SATO AKIKO IIHARA NAOYUKI SAKAI FUMINARI ITO MOTOYOSHI NOMIZU NORIO NISHI 《Fisheries Science》2002,68(4):904-912
ABSTRACT: Nucleoplasmin, first isolated from Xenopus laevis eggs, promotes nucleosome assembly. Hereby, we have purified a nucleoplasmin-like protein from carp ( Cyprinus carpio ) eggs using ion exchange and subsequent gel filtration columns. The protein was recognized by a polyclonal antiserum against Xenopus laevis nucleoplasmin and had an amino acid composition similar to other member of the nucleoplasmin family proteins. Partial amino acid sequences from the cyanogen bromide (CNBr)-cleaved fragments showed high homology with Xenopus nucleoplasmin. The protein was also found to form an oligomeric complex and to be phosphorylated. Moreover, this protein promoted sperm nuclear decondensation as well as that of nucleoplasmin from Xenopus laevis eggs. These results suggest that the fish protein isolated here is a member of nucleoplasmin family. 相似文献
85.
新城疫病毒某水禽分离株经鸡体传代后由非致病型转变为速发型的研究 总被引:8,自引:0,他引:8
于圣青 丁铲 NORIKO KISHIDA HIROSHI ITO HIROSHI KIDA KOICHI OTSUKI TOSHIHIRO ITO 《中国预防兽医学报》2003,25(1):59-64
最近,一株无毒力的新城疫病毒(NDV)在鸡体内繁殖时,变成了强毒株,但致今尚未能证实,经鸡体传代的野生水禽新城疫病毒是否也具有变成速发型毒株的能力,为了通过实验证明从水禽中分离的非致病型NDV可以转变为速发型病毒,我们通过在鸡体内传播鹅源性无毒力株,经气囊接种连续传代9次,随后再在鸡脑内传代5次,结果显示,该病毒的毒力变得很强,致死率可达100%,通过致病性试验证实,其具有典型的速发型病毒特征;融合蛋白裂解位点的序列分析表明,原始的分离株含有无毒力型毒株共有的裂解序列;E-R-Q-E-R/L,而通过鸡体反复传代后,该序列变为致癞 性毒株共有的序列:K-R-Q-K-R/F,这些结果表明,野生水禽中自然存在的无毒力毒株,具有无毒力株相应的序列,但当其在鸡群中传播时,则具有变成高致病性病毒的能力,同时研究表明,鸡体提供了该病毒从非致病型向致病型转变的选择机制。 相似文献
86.
Norihito Yamauchi Mamoru Satou Jyuichi Shimazu Takashi Shirakawa Seizo Horiuchi 《Journal of General Plant Pathology》2007,73(1):29-34
Race 2 isolates of Fusarium oxysporum f. sp. lactucae have been recognized as biotin auxotrophs and consequently have restricted growth on Puhalla's minimal medium (MM), which
contains no biotin. Biotin-autotrophic isolates were raised from race 2 isolates through cultural mutation that grew as well
on MM as they did on MM supplemented with biotin. These autotrophs were identical to the parental isolates in pathogenicity
on race differential cultivars of lettuce (Patriot, Banchu Red Fire, and Costa Rica No. 4), and thus were designated as race
2. A vegetative compatibility test indicated that the autotrophic isolates fell into the same vegetative compatibility group
as the parents. Culture filtrates of the autotrophs allowed abundant growth of the parental auxotroph on MM, and, through
a competitive enzyme-binding assay, biotin was detected in the culture filtrates. These results suggest that biotin auxotrophy
in the natural race 2 isolates has no direct relation to pathogenicity, qualitatively defined as physiological race, or to
vegetative compatibility. 相似文献
87.
Natsuki USHIGOME Sayaka WAKAYAMA Kango YAMAJI Daiyu ITO Masatoshi OOGA Teruhiko WAKAYAMA 《The Journal of reproduction and development》2022,68(4):262
Freeze-dried sperm (FD sperm) are of great value because they can be stored at room temperature for long periods of time, However, the birth rate of offspring derived from FD sperm is low and the step in the freeze-drying process particularly responsible for low offspring production remains unknown. In this study, we determined whether the drying process was responsible for the low success rate of offspring by producing vacuum-dried sperm (VD sperm), using mouse spermatozoa dried in a vacuum without being frozen. Transfer of embryos fertilized with VD sperm to recipients resulted in the production of several successful offspring. However, the success rate was slightly lower than that of FD sperm. The volume, temperature, and viscosity of the medium were optimized to improve the birth rate. The results obtained from a comet assay indicated that decreasing the drying rate reduced the extent of DNA damage in VD sperm. Furthermore, even though the rate of blastocyst formation increased upon fertilization with VD sperm, full-term development was not improved. Analysis of chromosomal damage at the two-cell stage through an abnormal chromosome segregation (ACS) assay revealed that reduction in the drying rate failed to prevent chromosomal damage. These results indicate that the lower birth rate of offspring from FD sperm may result from the drying process rather than the freezing process. 相似文献
88.
Seishiro CHIKAZAWA Yasutomo HORI Fumio HOSHI Kazutaka KANAI Naoyuki ITO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):843-846
In the present study, we examined the relationship between serum ferritin concentration
before treatment and survival time in dogs with multicentric lymphoma. Eighteen dogs with
multicentric lymphoma were enrolled in the study. When the dogs were classified into high
and low ferritin groups on the basis of their serum ferritin concentration (3,000
ng/ml cut-off value), the median survival time of dogs
with high concentrations (≥3,000 ng/ml, n=7) was 40
days, whereas it was 360 days among dogs with low concentrations (<3,000
ng/ml, n=11). This difference was statistically
significant (P=0.001). This finding suggests that the initial high level
of serum ferritin indicates short survival time in dogs with multicentric lymphoma.
Large-scale research is necessary to confirm this finding. 相似文献
89.
90.
Pramod DHAKAL Nobuo TSUNODA Rie NAKAI Tomoki KITAURA Takehiro HARADA Masahiro ITO Kentaro NAGAOKA Yuko TOISHI Hiroyuki TANIYAMA Watanabe GEN Kazuyoshi TAYA 《Journal of Equine Science》2011,22(2):29-36
Changes in follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin,
immunoreactive(ir)-inhibin, testosterone, estradiol-17β, and insulin-like growth factor
(IGF)-I in Thoroughbred stallions along with changes in prolactin secretion in geldings
were studied. The correlations of day-length with changes in the concentrations of these
hormones were also studied. Five stallions and thirteen geldings were employed to draw
blood samples in monthly basis and radioimmunoassay was performed to measure these
hormones. All hormones showed a seasonal pattern, the levels being highest during the
breeding season and lowest during the winter months. Most of the hormones were at their
highest concentration during the month of April, the mid of spring in northern hemisphere.
The concentration of circulating IGF-I also demonstrated seasonality, the peak lying on
the month of April. The plasma concentration of prolactin also increased during the
breeding season. This phenomenon was similar both in stallions and geldings although
geldings had lower concentration than that of stallions. The changes in concentration of
prolactin in stallions and geldings correlated more towards the day-length than towards
the temperature. These results clearly indicate the seasonality of pituitary and gonadal
hormones of Thoroughbred stallions, the activity being highest during the month of April
and May of the breeding season. 相似文献