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51.
In this article, we report on an estimation method for Young’s modulus that entails measuring only the stress wave propagation
velocity of timber built into structures such as wooden buildings. Methods of estimating Young’s modulus that use the stress
wave propagation velocity and characteristic frequency of timber in conjunction with timber density have long been used. In
this article, we propose a method of easily and accurately estimating Young’s modulus from the stress wave propagation velocity
without knowing the timber density. This method is based on a database of wood strength performance and density accumulated
from a variety of research data and the method estimates Young’s modulus by a simulation method. We compared the Young’s moduli
estimated by this method with those obtained by the bending test and by the measurement of the stress wave propagation velocity
and density, and found similar results. This coincidence suggests that the method of estimating Young’s modulus presented
in this article is valid. For example, the method is effective for convenient evaluation on site when determining whether
a wooden building’s structural components should be reused or replaced when repairing or remodeling a building. 相似文献
52.
Sakamoto A Yamaguchi Y Yamakawa S Nagatani M Tamura K 《Journal of toxicologic pathology》2011,24(1):81-85
We investigated a highly metastatic ovarian yolk sac carcinoma in a 52-week-old female Crl:CD(SD) rat. Macroscopically, the present case had severe ascites, bilateral ovarian masses and numerous nodules in the abdominal and thoracic cavities. Histopathologically, these masses and nodules were generally composed of two types of cells mimicking a parietal and visceral yolk sac. The parietal cells were round to polygonal, contained eosinophilic droplets and were arranged in nests and cords in the eosinophilic matrix. Both the intracytoplasmic droplets and the matrix were stained positively with PAS. The visceral cells were cylindriform, and proliferated in papillary and tubular patterns and occasionally formed Shiller-Duval body-like structures. In the dissemination sites, the neoplastic cells proliferated on the surface of the various tissues and often infiltrated into deeper parts of the tissues. Immunohistochemically, both neoplastic cells were positive for α-fetoprotein and keratin, and the eosinophilic matrix was positive for laminin. Ultrastructurally, the parietal cells had dilated rough endoplasmic reticulums, which were filled with electron-lucent laminated structures. The visceral cells had poorly to moderately developed intracytoplasmic organelles and were interconnected with desmosomes. Taken together, the present tumor was diagnosed as yolk sac carcinoma arising from the ovary and was characterized by not only high metastasis but also invasive infiltration with biphasic proliferation of the parietal and visceral cells. 相似文献
53.
Sakurada Y Sawai M Inoue K Shirota M Shirota K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(7):923-926
In order to understand ovarian toxicity of aryl hydrocarbon receptor (AhR) agonists, in situ gene expression of the AhR was examined during follicle development in immature rats. In situ hybridization on frozen sections of ovaries from 24-day-old Sprague-Dawley rats showed that the AhR mRNA was localized in the granulosa cells and occasionally in the theca cells of the follicles irrespective of the developmental stage. In situ gene quantification on granulosa cell layers collected by laser microdissection further revealed that the granulosa cells expressed less AhR mRNA according to development of belonging follicles, but more β-subunit of inhibin A mRNA, a quality control gene. These results may help to elucidate vulnerable developmental stages of follicles to toxicities of the AhR agonists. 相似文献
54.
Shiro Takeda Akiko Harauma Mariko Okamoto Hirofumi Enomoto Toshiji Kudo Takehito Suzuki Wataru Mizunoya Toru Moriguchi 《Animal Science Journal》2020,91(1)
This study aimed to investigate the effects of whey protein hydrolysate (WPH) on the growth and immunity of mouse pups in artificial rearing (AR) system. Mouse pups were reared in the AR system with artificial milk including 5% WPH (AR with WPH) or not (AR without WPH), and the remaining pups were reared by their mother (dam) for 14 days after birth. The body weight change and body weight gain rates in the AR with WPH group were significantly higher than those observed in the AR without WPH group and similar to those in the dam group. Moreover the feed and protein efficiencies in the AR with WPH group were significantly higher than those of the AR without WPH group. In addition, the supplement of WPH in the AR system was shown to significantly elevate the number of CD3+CD8+, B220+CD19+, IA/IE+CD11c+, and CD11b+ in the thymocyte and/or splenocyte, and the thymus weight. Furthermore, MALDI‐TOF/MS analysis identified the amino acid sequences corresponding to some peptides, and indicated that VRTPEVDDE had the highest relative intensity among the peptides from tested WPH. Therefore, WPH would be required to not only promote growth, but also exert immunomodulatory activities in mouse pups in AR system. 相似文献
55.
Takanori Imai Sousuke Inoue Naomi Ohdaira Yasuyuki Matsushita Rie Suzuki Mariko Sakurai José Manoel Henriques de Jesus Salete Kiyoka Ozaki Zenesio Finger Kazuhiko Fukushima 《Journal of Wood Science》2008,54(6):470-475
Heartwood extracts from Amazonian trees cumaru-ferro (Dipteryx odorata), jatoba (Hymenaea courbaril), and guarita (Astronium lecointei) exhibit antioxidant activities comparable with that of α-tocopherol, a well-known antioxidant. This article reports the characterization of the antioxidant compounds in the extracts
of the three heartwoods. Silica gel column chromatography of the cumaru-ferro EtOAc extract yielded (−)-(3R)-7,2′,3′-trihydroxy-4′-methoxyisoflavan and (+)-(3R)-8,2′,3′-trihydroxy-7,4′-dimethoxyisoflavan. Silica gel column chromatography followed by preparative high-performance liquid
chromatography of the jatoba EtOAc extract yielded (−)-fisetinidol and (+)-trans-taxifolin. Chemical structures were assigned using electron-ionization mass spectrometry, 1H and 13C nuclear magnetic resonance (NMR) spectroscopy including nuclear Overhauser effect spectroscopy (NOESY), as well as optical
rotation and circular dichroism. Gas chromatography-mass spectrometry demonstrated that the isolated compounds were predominant
in the EtOAc extracts. In the guarita EtOAc extract, catechin and gallic acid were identified by comparing their retention
times and mass fragmentation patterns with those of authentic samples. Antioxidant activity determined by the 1,1-diphenyl-2-picrylhydrazyl
assay demonstrated that all these compounds had activities comparable with that of α-tocopherol.
Part of this report was presented at the 57th Annual Meeting of the Japan Wood Research Society, Hiroshima, August 2007 相似文献
56.
The hyphal sheath is a morphological feature of many kinds of fungi. Although the fine structures of the sheath have been
studied in detail by a number of electron microscopy techniques, the function and physiology of the hyphal sheath are not
yet clarified. One reason for this is that the hyphal sheath is a colorless, mucilaginous, and delicate material so that it
is not easily identified. We developed a simple method to visualize and identify the hyphal sheath of the white-rot fungus
Phanerochaete crassa WD1694. The small mycelial pellets in shaken liquid cultures of P. crassa WD1694 were stained directly with phloxine B. Both the hyphae and the hyphal sheath that filled the gaps between each of
the hyphae were visualized and observed by light microscopy. The stained hyphae were further studied by transmission electron
microscopy, atomic force microscopy, and fl uorescence microscopy. Based on these observations, we confirmed that the staining
of the hyphae was also due to the presence of the hyphal sheath that closely covered the fungal cell wall. These results clearly
showed that the hyphal sheath was selectively stained with phloxine B and could be observed and identified by conventional
light microscopy.
Part of this report was presented at the 50th Lignin Symposium, Nagoya, October 2005 相似文献
57.
K Ochiai K Jin C Itakura M Goryo K Yamashita N Mizuno T Fujinaga T Tsuzuki 《Avian diseases》1992,36(2):313-323
During spring 1989, thirty-three whooper swans (Cygnus cygnus) died at Lake Miyajima in Hokkaido, Japan; 15 were examined. The birds were diagnosed as having subacute lead poisoning due to ingestion of spent lead shot. The main gross findings were bile-stained liver, edematous or gelatinous bone marrow, bile-stained lining with hyperkeratosis and lead pellets in the gizzard, and proventricular impaction. Histopathologically, there was lead-hemolytic jaundice of the liver, hemosiderosis in the liver and spleen, and hypoplasia of the bone marrow with increased numbers of polychromatic erythroblasts. Acid-fast intranuclear inclusion bodies were seen in kidneys of seven swans. Under electron microscopy, inclusion bodies had frayed contours and consisted of high-electron-dense fine granules. The lead concentration of the liver ranged from 5.5 to 44.3 mg/kg wet weight. It was suggested that these changes resulted from excess breakdown of erythrocytes, inhibition of heme synthesis, and impaired erythropoiesis caused by lead shot. 相似文献
58.
Hideharu Ochiai Nobuya Hishiyama Shin Hisamatsu Nobuyuki Kanemaki 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(2):203-205
We investigated the expression of aquaporin 1 (AQP1) in tissues from canines with an inherited anomaly that causes their erythrocytes to have high K+. Northern blot analysis revealed abundant AQP1 expression in lung and kidney, though little expression was found in spleen. Using anti-C-terminus for dog AQP1, abundant expression was shown in kidney, trachea, and eye, but little expression was shown in pancreas and cerebrum, indicating that AQP1 expression in canine tissues is similar to that noted in other mammals. 相似文献
59.
Yoshiyuki Kiyono Yukihito Ochiai Yukihiro Chiba Hidetoshi Asai Kazuki Saito Tatsuhiko Shiraiwa Takeshi Horie Visone Songnoukhai Viengmany Navongxai Yoshio Inoue 《Journal of Forest Research》2007,12(5):371-383
In northern Lao People’s Democratic Republic, rising human population has drastically reduced the fallow period of slash-and-burn
agriculture which has led to a considerable decrease in the carbon stock in these communities. We estimated chronosequential
changes in the communities' carbon stocks, and established the relationship between the fallow period and fallow-period-average
carbon stocks in three carbon pools of bamboo-dominated communities in hilly areas of the Luang Prabang Province, northern
Lao People’s Democratic Republic. Based on measurements by destructive sampling, we devised a model and root-to-shoot ratios
for estimating bamboo biomass. In six secondary plant communities established after slash-and-burn cropping, we estimated
community biomass using the above model and others, and measured deadwood and litter stocks. The communities’ biomass and
deadwood significantly increased with time after the last cropping and the former reached about 100 Mg ha−1 after 15 years, whereas litter stocks did not show significant trends over time. Extending the fallow period from 2 to 5 years
would increase fallow-period-average carbon stock from 14.2 to 25.1 Mg C ha−1. The overstory height was significantly correlated with biomass, deadwood, and litter carbon stocks of these communities.
Based on our findings, changes in a community’s carbon stocks can be estimated using the changes in overstory height, which
should be taken into account in future studies to reduce uncertainty in estimating carbon stocks in tropical ecosystems. 相似文献
60.
Mariko Shoji Hidenori Sato Remi Nakagawa Ryo Funada Takafumi Kubo Shinjiro Ogita 《Journal of Forest Research》2006,11(6):449-453
The effect of an osmoticum, polyethylene glycol (PEG), on somatic embryo production was examined using embryogenic cells of
Pinus densiflora. In the basal medium containing 30 μM abscisic acid and 6% maltose, the quality of the embryos formed was poor even though
somatic embryos were produced. The addition of PEG with molecular weight of 4000 or 8000 significantly enhanced the development
of both the quality and quantity of somatic embryos. Furthermore, higher levels of a constant osmotic pressure with PEG 8000
in a range from about 300 to 450 mmol/kg could remarkably enhance the morphogenesis of somatic embryos and their number of
embryos produced. A higher stable osmotic pressure with an appropriate molecular weight of PEG is a key factor for the production
of good quality somatic embryos in P. densiflora. 相似文献