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101.
Chi H Shinohara M Yokomine T Sato M Takao S Yoshida M Miyoshi K 《The Journal of reproduction and development》2012,58(1):69-76
RNA interference (RNAi) technology using small interfering RNAs (siRNA) has been widely used as a powerful tool to knock down gene expression in various organisms. In pig preimplantation embryos, no attempt to suppress the target gene expression with such technology has been made. The purpose of this study is to demonstrate that the RNAi technology is useful for suppression of endogenous target gene expression at an early stage of development in pigs. Alpha-1,3-Galactosyltransferase (α-GalT) is an enzyme that creates the Galα1-3Gal (α-Gal) epitope on the cell surface in some mammalian species, and removal of the epitope is considered to be a prerequisite for pig-to-human xenotransplantation. We decided to suppress the endogenous α-GalT mRNA expression in pig early embryos, since reduction of α-GalT synthesis is easily monitored by cytochemical staining with Bandeiraea simplicifolia isolectin-B(4), a lectin that specifically binds to the α-Gal epitope, and by RT-PCR analysis. Cytoplasmic microinjection of double-stranded RNA and pronuclear injection of an siRNA expression vector into the embryos generated in vitro resulted in a significant reduction in expression of the α-GalT gene and α-Gal epitope in blastocysts, at which stage the α-Gal epitope is abundantly expressed. Somatic cell nuclear transfer of embryonic fibroblasts stably transfected with an siRNA expression vector also led to a significant reduction in the level of α-GalT mRNA synthesis together with decreased amounts of the α-Gal epitope at the blastocyst stage. These results indicate that the RNAi technology is useful for efficient suppression of a target gene expression during embryogenesis in pigs and suggest the possibility of production of siRNA-expressing pigs for use in xenotransplantation. 相似文献
102.
Mariko?YamasakiEmail author Chika?Tsuzuki Yasutoshi?Sasaki Yuji?Onishi 《Journal of Wood Science》2017,63(3):225-235
The effect of moisture content on the stress wave propagation velocity was investigated in order to estimate the Young’s modulus of full-scale timbers in an air-drying state using the measurement of stress wave propagation velocity above the fiber saturation point. Using Japanese cedar lumber, the velocity and the density under high-moisture condition and air-drying states were measured respectively; after measuring the modulus of elasticity in an air-drying state, the moisture content of each condition was measured. By performing numerical analysis on these data, the relationship between the moisture content and the rate of change of velocity of full-scale timbers was derived. This relationship was used to estimate the Young’s modulus of the timber in the air-drying state from the velocity in high-moisture condition. First, the velocity and the Young’s modulus in an air-drying state were estimated accurately from its density, moisture content and velocity under high-moisture condition. In cases where the density could not be measured, using the database of mechanical properties with the Monte Carlo simulation method, the Young’s modulus of the full-scale timber in an air-drying state might be estimated within 20% accuracy from its moisture content and velocity under high-moisture condition. 相似文献
103.
Peñalvo JL Adlercreutz H Uehara M Ristimaki A Watanabe S 《Journal of agricultural and food chemistry》2008,56(2):401-409
Lignans constitute a group of phytochemicals widely distributed in the human diet. Once ingested, most dietary lignans are metabolized by the gut microflora to enterolactone and enterodiol, also known as enterolignans. Together with isoflavones and coumestrol, enterolignans have been traditionally classified as phytoestrogens, plant-derived compounds that exhibit estrogen-like activity. In addition to a higher intake of vegetables, many studies have suggested that the presence of phytoestrogens in the Japanese diet is one of the factors that might explain the reduced incidence of certain chronic diseases in Japanese populations compared with Western countries. Being a vegetable-based diet, exposure to dietary lignans should be high, but to assess this exposure, a lignan food database is required. Stable isotope-dilution gas chromatography coupled with mass spectrometry was used to quantify six plant lignans in 86 food items commonly consumed in Japan. These data will complement the previous databases and most importantly expand the knowledge of occurrence of lignans in food to Eastern diets. 相似文献
104.
From among 419 wood-rotting fungi 10 were selected by the Poly R decolorization test, and their ability to bleach hardwood kraft pulp was assayed. Of the 10 selected, 6 fungi (i.e.,Phanerochaete crassa WD1694 and F150;Pleurotus pulmonarius PSC-H, PSC-M, and PSC-T;and Pleurotus species A119) showed much higher bleaching ability thanPhanerochaete chrysosponum BKMF1767 orTrametes versicolor WD1670, both of which are well-known high ligninolytic fungi.P. crassa WD1694 had the highest bleaching ability among the selected strains, and it increased the pulp brightness from 28 to 54, with a corresponding decrease in kappa number from 16 to 6 after 10 days of cultivation and alkali extraction. MnP was a predominant ligninolytic enzyme ofP. crassa WD1694 during the biobleaching.This research was presented in part at the 46th Annual Meeting of the Japan Wood Research Society, Kumamoto, April 1996 相似文献
105.
The white-rot fungus Phanerochaete crassa WD1694 was cultivated and peroxidase activity staining was performed to determine the sites at which the extracellular peroxidase
reaction actually occurs in vivo. Although the ligninolytic peroxidases were found in the culture filtrates, the culture medium
did not show a color reaction. However, a particularly strong color reaction was observed on the hyphal tips. Visible spectra
and absorbance of the staining were analyzed by microspectrophotometry, and the catalytic rates of the peroxidase reaction
at the hyphal tips were calculated. The estimated catalytic rate of the peroxidase reaction at the hyphal tips peaked at 794
μM/min, expressed as the consumption rate of H2O2, on day 3 of the cultivation. Analysis of the extracellular enzyme eluted with 0.1% Tween 80 from the mycelium revealed that
manganese peroxidase accounted for 89% of all the peroxidase activity measured. The results clearly showed the existence of
the concentrated manganese peroxidase reaction around the hyphal tips of the organism. 相似文献
106.
In many temperate evergreen plant species, reductions in turgor loss point of leaves (Psi(tlp)) and leaf osmotic potential at full turgor (pi(sat)) occur from late summer to winter. To test the hypothesis that this seasonal change in leaf water relations is driven by root temperature, we manipulated the temperature of the roots and shoots of Cryptomeria japonica D. Don seedlings separately. Whole-plant warming diminished the seasonal changes in shoot water relations observed in the control plants, whereas shoot warming did not. Compared with the controls, root warming diminished the change in Psi(tlp) but not in pi(sat), whereas cooling accelerated the seasonal changes in shoot water relations. These results indicate that: (1) temperature responses of roots are involved in the seasonal changes in Psi(tlp) from late summer to winter; and (2) root temperature is partly responsible for the simultaneous changes in pi(sat). Whole-plant cooling caused increased root hydraulic resistance, suggesting that seasonal changes in shoot water relations represent adaptive responses to increased root hydraulic resistance at low root temperatures. 相似文献
107.
Daiki KATO Mariko OISHI Koichi OHNO Ko NAKASHIMA Atsuhito WADA Tatsushi MORITA Soichi IMAI Masaya TSUBOI James K. CHAMBERS Kazuyuki UCHIDA Hajime TSUJIMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1499-1502
Ollulanus tricuspis is a small nematode parasite of the
stomach, and its infection has been reported worldwide in cats but only one report in dogs
as post-mortem diagnosis. Two dogs, kept in the Tokyo area, were presented for chronic
vomiting. Chronic gastritis was diagnosed histologically, and many nematodes were detected
in endoscopically-biopsied gastric samples and in the mucus of vomitus in both dogs. The
parasites were small (<1 mm), and their morphological characteristics were consistent
with those previously reported for O. tricuspis. The symptoms in one dog
completely disappeared after anthelmintic therapy. To our knowledge, this is the first
report describing ante-mortem diagnosis of spontaneous gastric O.
tricuspis infection in dogs in which infectivity and pathogenicity of the
nematode are suggested. 相似文献
108.
Kohei TORIKAI Kazuma SHIMIZU Hiroaki NAGATOMO Mariko KASAI Megumi KATO-ITOH Yuko KAMADA Ikue SHIBASAKI Hyojung JEON Riko KIKUCHI Sayaka WAKAYAMA Fabian SUCHY Hiromitsu NAKAUCHI Teruhiko WAKAYAMA Eiji MIZUTANI 《The Journal of reproduction and development》2023,69(1):48
We examined various methods to enhance the accessibility of intracytoplasmic sperm injection (ICSI) technology to more users by making the technique easier, more efficient, and practical. First, the methods for artificially removing the mouse sperm tail were evaluated. Trypsin treatment was found to efficiently remove the sperm tails. The resultant sperm cells had a lower oocyte activation capacity; however, the use of activated oocytes resulted in the same fecundity as that of fresh, untreated sperm. Pre-activated oocytes were more resistant to physical damage, showed higher survival rates, and required less time per injection. Testing this method in rats yielded similar results, although the oocyte activation method was different. Remarkably, this method resulted in higher birth rates of rat progeny than with conventional methods of rat ICSI. Our method thereby streamlines mouse and rat ICSI, making it more accessible to laboratories across many disciplines. 相似文献
109.
Satomi Ushizaka Kohji Sugie Masumi Yamada Mariko Kasahara Kenshi Kuma 《Fisheries Science》2008,74(5):1137-1145
The significance of Mn and Fe for the growth of a coastal marine diatom Thalassiosira weissflogii was investigated by performing culture experiments containing macronutrients with either Mn or Fe, or both. Only the addition
of both Mn and Fe induced the highest growth rates and maximal cell yields. Maximal growth was maintained in continuous culture
media, which were repeatedly prepared by an inoculation of pre-culture and the addition of both Mn and Fe to the control culture
medium containing macronutrients. In particular, it was found that the full growth recovery in Mn-sufficient medium (without
added Fe) is accomplished by the addition of Fe even after several days’ incubation. On the contrary, there was no sufficient
growth recovery by the addition of Mn after a long incubation time in Fe-sufficient medium but without additional Mn. These
results suggest that T. weissflogii in Mn-sufficient waters retains the ability for full physiological recovery for a long time, probably resulting from the
decrease in the oxidative stress of phytoplankton by the production of antioxidant enzyme Mn superoxide dismutase during a
long incubation period. 相似文献
110.
Otsuki M Kusumoto K Murakami Y Kanayama M Takeuchi S Takahashi S 《The Journal of reproduction and development》2007,53(1):59-68
Interleukin-18 (IL-18) is a proinflammatory cytokine involved in chronic inflammation, autoimmune diseases, and a variety of cancers, and is expressed in mouse uteri. Our previous study suggested that IL-18 acts as a paracrine factor, regulating endometrial function. To elucidate the physiological roles of IL-18 in the mouse endometrium, the expression of the IL-18 receptor (IL-18R) alpha subunit was analyzed. IL-18Ralpha mRNA was expressed in several mouse organs in addition to the endometrium. In situ hybridization analysis using a biotin-labeled mouse IL-18Ralpha riboprobe demonstrated that IL-18Ralpha mRNA expression was detected in glandular epithelial cells, stromal cells around uterine glands, and myometrial cells in the mouse uterus, suggesting that these cells are targets for IL-18. The uterine IL-18Ralpha mRNA expression level changed with the estrous cycle. The uterine IL-18Ralpha mRNA levels of estrous mice were higher than those of diestrous mice. In addition, the IL-18Ralpha mRNA levels in uteri at 3 and 14 days after ovariectomy were higher than those at diestrus and decreased following treatment with estradiol-17beta or progesterone. These findings suggest that IL-18Ralpha gene expression is regulated by estrogen and progesterone and that the uterine IL-18 system is involved in the regulation of uterine functions in a paracrine manner. 相似文献