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221.
Kazutaka Kawamura Motoki Shimizu Takahiro Kawanabe Zujing Pu Taro Kodama Makoto Kaji Kenji Osabe Ryo Fujimoto Keiichi Okazaki 《Euphytica》2017,213(1):28
Cabbage (Brassica oleracea L. var. capitata) is an important vegetable worldwide. Most Japanese commercial cultivars of cabbage use an F1 hybrid seed production system. The purity of F1 hybrid seeds is important and the assessment of purity based on DNA markers can be highly accurate. In addition, selection of agronomically important traits such as disease resistance based on DNA markers is useful for breeding of cabbage. The aim of this study is to demonstrate the effectiveness of DNA marker-assisted selection in cabbage. In this study we distinguished the parental S haplotypes in 35 F1 hybrid cultivars by combining several linked DNA markers. Thirty-one highly polymorphic simple sequence repeats (SSR) markers were screened from 175 reported SSR markers, which are useful for assessment of the purity of F1 hybrid seeds. We examined the relationship between the DNA marker based genotype and the phenotype by an inoculation test of clubroot disease. A co-dominant PCR–RFLP marker was developed for selection of Fusarium yellows resistance and the genotypes using this marker were consistent with inoculation test in all tested samples. 相似文献
222.
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
223.
We examined an alternative natural regeneration practice with a scarification treatment, in which removed soil is replaced
on the scarified area, in northern Japan. The effect of the soil replacement on tree establishment was quite obvious; the
basal area of trees, composed mostly of Betula ermanii, in the soil-replaced site was about 150-fold greater than that of the normally treated site. The greater growth rates together
with higher density, both of which seemed to be enhanced by improved (i.e., deeper, tender, and nutrient-rich) soil properties,
produced the marked difference to the normally treated site. The expected enhancement of species diversity owing to utilizing
buried seeds in the replaced soil was not found. The current study revealed that the soil replacement could substantially
improve forest restoration management with emphasis on biomass production for large nonwooded sites. 相似文献
224.
Katayama Satoshi Yamada Hidetoshi Onodera Keiichi Masuda Yoshio 《Fisheries Science》2019,85(3):475-481
Fisheries Science - The age and growth of Japanese jack mackerel Trachurus japonicus from Oita and Miyagi Prefectures were investigated by means of otolith sectioning. Different types of opaque... 相似文献
225.
Masayuki Sato Koji Yachiguchi Keiichi Motohashi Yukio Yaguchi Yoshiaki Tabuchi Yoichiro Kitani Takahiro Ikari Shouzo Ogiso Toshio Sekiguchi Tran Ngoc Hai Do Thi Thanh Huong Nguyen Viet Hoang Makoto Urata Hiroyuki Mishima Atsuhiko Hattori Nobuo Suzuki 《Fisheries Science》2017,83(4):543-550
The influence of sodium fluoride (NaF) on calcium metabolism was examined in nibbler fish (marine teleosts). Two days after the administration of NaF (5 μg/g of body weight) (around 10?4 M in fish), we showed that plasma calcium levels significantly decreased in NaF-treated nibbler fish. In addition, we detected fluoride in the treated scales by use of a scanning electron microscope with an energy-dispersive X-ray microanalysis, indicating that NaF directly affects their scales. Therefore, the influence of NaF on osteoblasts and osteoclasts in the scales was examined. In the scales of NaF-injected nibbler fish, tartrate-resistant acid phosphatase (TRAP) (osteoclastic marker enzyme) decreased, although alkaline phosphatase (osteoblastic marker enzyme) was activated. To confirm the effect of NaF on osteoclasts, furthermore, the mRNA expressions of osteoclastic markers (matrix metalloproteinase-9 and TRAP) were decreased significantly 2 days after incubation. In barred knifejaws, plasma calcium levels decreased as they did in nibbler fish. Therefore, NaF functions in both osteoblasts and osteoclasts and then influences calcium metabolism in marine fish. In the marine environment, high levels of fluoride (1.2–1.5 mg F?/l) (around 10?5–10?4 M) are present in seawater. It is probable that teleosts living in seawater efficiently use fluoride to regulate their blood calcium levels. 相似文献
226.
Md. Masud Karim Asfakun Siddika Nazmoon Naher Tonu Delwar M. Hossain Md. Bahadur Meah Takahiro Kawanabe Ryo Fujimoto Keiichi Okazaki 《Breeding Science》2014,63(5):495-502
Brassica napus is a leading oilseed crop throughout many parts of the world. It is well adapted to long day photoperiods, however, it does not adapt well to short day subtropical regions. Short duration B. napus plants were resynthesized through ovary culture from interspecific crosses in which B. rapa cultivars were reciprocally crossed with B. oleracea. From five different combinations, 17 hybrid plants were obtained in both directions. By self-pollinating the F1 hybrids or introgressing them with cultivated B. napus, resynthesized (RS) F3 and semi-resynthesized (SRS) F2 generations were produced, respectively. In field trial in Bangladesh, the RS B. napus plants demonstrated variation in days to first flowering ranging from 29 to 73 days; some of which were similar to cultivated short duration B. napus, but not cultivated short duration B. rapa. The RS and SRS B. napus lines produced 2–4.6 and 1.6–3.7 times higher yields, respectively, as compared to cultivated short duration B. napus. Our developed RS lines may be useful for rapeseed breeding not only for subtropical regions, but also for areas such as Canada and Europe where spring rapeseed production can suffer from late spring frosts. Yield and earliness in RS lines are discussed. 相似文献
227.
ADAM PRINK DVM KEI HAYASHI DVM PhD Diplomate ACVS SUN-YOUNG KIM DVM MS JAMES KIM DVM AMY KAPATKIN DVM MS Diplomate ACVS 《Veterinary surgery : VS》2010,39(1):65-70
Objective— To evaluate whether synovial fluid concentrations of an osteoarthritis biomarker in dysplastic canine elbows with medial coronoid disease (MCD) are elevated compared with unaffected elbows and to determine if these concentrations correlate to the degree of articular cartilage damage.
Study Design— Cross sectional clinical study.
Animals— Dogs (n=19; 35 elbows) with MCD and dogs (8; 16 elbows) with unaffected elbows.
Methods— Concentrations of a collagenase-generated cleavage neoepitope of type II collagen (Col2-3/4Clong mono , or C2C) in joint fluid from elbows were analyzed and compared between dogs with MCD and unaffected dogs. Correlation of C2C concentration with subjective grading of articular cartilage surface damage was also evaluated.
Results— Mean (±SD) C2C concentration from MCD dogs was significantly higher (112.3±24.8 ng/mL) than in unaffected dogs (76.1±16.9 ng/mL; P <.05). There was a moderate correlation between cartilage damage grade and increasing C2C concentrations ( P <.05, r=0.62)
Conclusion— C2C concentrations are elevated in the synovial fluid of dogs with MCD compared with unaffected elbows, and a moderate, significant correlation was identified between these concentrations and subjective grading of articular cartilage damage.
Clinical Relevance— This preliminary data suggest that C2C concentrations in synovial fluid may have potential as a biomarker for diagnosis of articular cartilage damage associated with MCD and as a means of objectively determining the degree of articular cartilage damage. 相似文献
Study Design— Cross sectional clinical study.
Animals— Dogs (n=19; 35 elbows) with MCD and dogs (8; 16 elbows) with unaffected elbows.
Methods— Concentrations of a collagenase-generated cleavage neoepitope of type II collagen (Col2-3/4C
Results— Mean (±SD) C2C concentration from MCD dogs was significantly higher (112.3±24.8 ng/mL) than in unaffected dogs (76.1±16.9 ng/mL; P <.05). There was a moderate correlation between cartilage damage grade and increasing C2C concentrations ( P <.05, r=0.62)
Conclusion— C2C concentrations are elevated in the synovial fluid of dogs with MCD compared with unaffected elbows, and a moderate, significant correlation was identified between these concentrations and subjective grading of articular cartilage damage.
Clinical Relevance— This preliminary data suggest that C2C concentrations in synovial fluid may have potential as a biomarker for diagnosis of articular cartilage damage associated with MCD and as a means of objectively determining the degree of articular cartilage damage. 相似文献
228.
229.
Takayuki FUJIWARA Keiichi MURAKAMI Toshihiko TANAHASHI Wataru OYANAGI 《Soil Science and Plant Nutrition》2009,55(1):170-178
Recently, acid detergent analysis has been reported to provide valid data to evaluate decomposition properties and to determine the available nitrogen (AVN) of organic materials, such as compost. However, this methodology requires complex procedures and creates considerable costs. As an alternative, near infrared spectroscopy (NIRS) was evaluated as a simple method to determine acid detergent fiber (ADF), acid detergent lignin (ADL) and acid-detergent-soluble organic matter (ADSOM), in order to evaluate the decomposition properties of cattle and swine manure compost. To establish an easy and accurate method of estimating AVN in cattle and swine manure compost, the accuracies of direct estimations of AVN by NIRS in incubation experiments and indirect estimations by NIRS based on acid-detergent-soluble nitrogen (ADSN) or total nitrogen (TN) were examined. The reflectance spectra of freeze-dried and milled compost samples were determined using a scanning monochromator. Second derivative spectra and multiple regression analysis were used to develop calibration equations for each constituent. The calibration equations for ADF, ADL and ADSOM were "successful" according to commonly applied criteria. Acid-detergent-soluble nitrogen was found to be more suitable than TN for estimating AVN in cattle and swine manure compost. As the accuracies of the estimations of ADSN and TN by NIRS were comparable, the estimation of AVN based on ADSN as determined by NIRS was more accurate than that based on TN determined by NIRS. The direct prediction of AVN through NIRS was not as accurate as the estimation of AVN based on ADSN determined by NIRS. We conclude that NIRS is a practicable alternative to the time-consuming acid detergent analysis of cattle and swine compost, and that ADSN as determined by NIRS is useful for estimating AVN in the compost. 相似文献
230.
Mumi Kikuchi Miwa Suzuki Keiichi Ueda Hirokazu Miyahara Senzo Uchida 《Fisheries Science》2011,77(5):795-798
Entanglement in fishing gear occurs in endangered manatees and may result in serious injury or death. Such incidents may happen
more frequently at night when the animal’s visual sense is limited. In this study, we examined the differences in behavioral
response of captive manatees to a net obstacle during light (day) and dark (night) periods. We used a plastic net as the obstacle,
and video-recorded the manatees’ behavior. The experiments showed that captive manatees avoided the obstacle during the day
more frequently than at night, which suggests that the manatees can perceive the obstacle more readily during light periods.
However, there was no difference in the frequency of bumping or actively touching the obstacle between light and dark periods.
The results suggest that the manatees can recognize the net obstacle even at night by purposely touching it, but they avoid
it less frequently, and that entanglement during light periods may occur during accidental bumping, rather than from a failure
to recognize it altogether. 相似文献