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281.
The relationship between the arrangement of wood strands at the surface of OSB and the modulus of rupture determined by image analysis 总被引:1,自引:0,他引:1
The objective of this paper is to investigate the relationship between the arrangement of wood strands at the surface of
oriented strand board (OSB) and the modulus of rupture (MOR) determined by applying the technique of image analysis (IA).
Fiber orientation was measured manually. In addition a CCD (charge coupled device) digital camera was used to automatically
measure the fiber orientation at the surface of OSB. The total number of OSB samples evaluated was equal to 55, but variation
in density was small and the coefficient of variation was only 4%. In contrast, the variation in MOR is wide and the coefficient
of variation is 17%. Thus, the variation in density of OSB does not reflect variations in MOR. The relationship between the
MOR and the average angle of fiber orientation resulted in a weak negative correlation (r=−0.44) as might be expected, as
better axial orientation should improve MOR. The average strand area gave no correlation with MOR. Clearly, large strands
which should enhance MOR may be heavily disoriented, whereas small strands which have less influence on the MOR might be well
oriented. Hence no correlation between MOR and average strand area is observed. The prediction of MOR by using a multiple
linear regression equation including density and fiber orientation factors is only moderately successful. Hence another factor
must be identified to predict MOR accurately. The CCD camera measures fiber orientation at the OSB surface effectively.
Received 29 March 1999 相似文献
282.
Fiber charge characteristics of pulp suspensions containing aluminum sulfate were investigated with relation to adsorption behavior of aluminum components on the pulp fibers by streaming potential measurement using a particle charge detector, X-ray photoelectron spectroscopy, and X-ray fluorescence analysis. When aluminum sulfate was added to a pulp suspension prepared using deionized water, a streaming potential of the suspension went from negative to slightly negative according to the adsorption of aluminum components on the pulp fibers. Subsequent addition of a dilute NaOH solution to the suspension drastically cationized the fibers in the pH range of around 5 by predominant and homogeneous adsorption of cationic aluminum complexes on the fiber surfaces. However, the aluminum flocs that formed heterogeneously on the fiber surfaces at higher pH by further alkali addition made nearly no contribution to cationization of the fibers, although the abundant aluminum components were retained in the pulp sheets. Therefore, only aluminum cations adsorbed uniformly on the fiber surfaces perform well to control the charge properties of the pulp fibers at the wet end; and the preferential aluminum adsorption behavior on the fiber surfaces, by utilizing the required amounts of hydroxyl ions, probably accounts for the effective cationization of the fibers under acidic to neutral papermaking conditions.This research was presented in part at the presymposium of the International Symposium on Wood and Pulping Chemistry, Seoul, June 1999; at the International Symposium on Environmentally Friendly and Emerging Technologies for a Sustainable Pulp and Paper Industry, Taipei, April 2000; and at the 2000 annual meeting of the Society of Fiber Science and Technology, Japan, Kyoto, June 2000 相似文献
283.
The strategy for implementing silvicultural practices in Japanese plantation forests was examined to achieve a carbon uptake of 13.0 Mt-C year–1, which was capped by the Marrakesh Accords, during the first commitment period, 2008–2012. The plantation forests that implemented silvicultural practices in the period 1990–2012 (FM plantation forests) were identified in compliance with the hypothesized identification rules, and carbon uptake in the forests was estimated using a simple model composed of simulation and optimization components on the assumption that whole plantation forest is classified into only two groups. Furthermore, parametric analysis was conducted to investigate the relationships among three factors: (1) the average annual harvesting volume (including thinning) in plantation forests during the first commitment period, (2) the total area of FM plantation forests in 2012, and (3) the average annual amount of carbon to be sequestered in FM plantation forests during the first commitment period. The results imply that young stands have to be prioritized in implementing silvicultural practices under any harvesting plan and carbon sequestration goal, and that FM plantation forests sequestered 8.0–10.5 (Mt-C year–1) carbon in inverse proportion to the harvesting volume of 21.0–14.0 million m3 year–1 (log volume), assuming that most of the plantation forests were incorporated into them. 相似文献
284.
Hirai T Nunoya T Azuma R 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(6):641-643
A goat with neurologic signs had multifocal abscesses containing sulfur granules in the right brain and temporal bone. Histologically, the lesions consisted of pyogranulomas with several radiating bacterial colonies of various sizes. A tangled mass of filamentous and gram-positive bacteria was recognized in the central part of the colony. Actinomyces naeslundii antigen was detected in the colonies of bacteria in the brain and neighboring bone tissue by immunohistochemistry. Actinomycosis involving the central nervous system (CNS) and temporal bone is rare in animals. Cerebral infection with A. naeslundii may have resulted from direct extension from cervicofacial regions because the CNS lesions were distributed asymmetrically and were continuous with the right temporal bone. 相似文献
285.
Satoshi Kambayashi Kouji Minami Yuka Ogawa Takehiro Hamaji Chung Chew Hwang Masaya Igase Hiroko Hiraoka Takako Shimokawa Miyama Shunsuke Noguchi Kenji Baba Takuya Mizuno Masaru Okuda 《Canadian journal of veterinary research》2015,79(3):201-209
The DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT) causes resistance to nitrosoureas in various human cancers. In this study, we analyzed the correlation between canine lymphomas and MGMT in vitro. Two of five canine lymphoma cell lines required higher concentrations of lomustine to inhibit cell growth by 50%, but their sensitivity to the drug increased when they were cultured with an MGMT inhibitor. Fluorometric oligonucleotide assay and real-time polymerase chain reaction of these cell lines revealed MGMT activity and high MGMT mRNA expression, respectively. We analyzed the methylation status of the CpG islands of the canine MGMT gene by the bisulfite-sequencing method. Unlike human cells, the canine lymphoma cell lines did not show significant correlation between methylation status and MGMT suppression levels. Our results suggest that in canine lymphoma MGMT activity may influence sensitivity to nitrosoureas; thus, inhibition of MGMT activity would benefit nitrosourea-resistant patients. Additional studies are necessary to elucidate the mechanism of regulation of MGMT expression. 相似文献
286.
Tom ICHINOHE Nobuo KANNO Yasuji HARADA Takuya YOGO Masahiro TAGAWA Satoshi SOETA Hajime AMASAKI Yasushi HARA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):761-770
Degenerative cranial cruciate ligament (CCL) rupture is characterized histologically by
degenerating extracellular matrix (ECM) and chondroid metaplasia. Here, we describe the
progression of chondroid metaplasia and the changes in the expression of ECM components in
canine CCL rupture (CCLR). CCLs from 26 stifle joints with CCLR (CCLR group) and normal
CCLs from 12 young beagles (control group) were examined histologically and
immunohistochemically for expression of type I (COLI), type II (COLII), type III collagen
(COLIII) and Sry-type HMG box 9 (SOX9). Cell density and morphology of CCLs were
quantified using hematoxylin–eosin staining. The percentage of round cells was higher in
the CCLR group than in controls. COLI-positive areas were seen extensively in the
connecting fibers, but weakly represented in the cytoplasm of normal CCLs. In the CCLR
group, there were fewer COLI-positive areas, but many COLI-positive cells. The percentages
of COLII-, COLIII- and SOX9-positive cells were higher in the CCLR group than in controls.
The number of spindle cells with perinuclear halo was high in the CCLR group, and most of
these cells were SOX9-positive. Deposition of COLI, the main ECM component of ligaments,
decreased with increased COLIII expression in degenerated CCL tissue, which shows that the
deposition of the ECM is changed in CCLR. On the contrary, expression of SOX9 increased,
which may contribute to the synthesis of cartilage matrix. The expression of COLII and
SOX9 in ligamentocytes showed that these cells tend to differentiate into
chondrocytes. 相似文献
287.
Masaya IGASE Chung Chew HWANG Matt COFFEY Masaru OKUDA Shunsuke NOGUCHI Takuya MIZUNO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):541-548
Oncolytic virotherapy is a new strategy for cancer treatment for humans and
dogs. Reovirus has been proven to be a potent oncolytic virus in human medicine. Our
laboratory has previously reported that canine mast cell tumor and canine lymphoma were
susceptible to reovirus. In this study, canine solid tumor cell lines (mammary gland
tumor, osteosarcoma and malignant melanoma) were tested to determine their susceptibility
towards reovirus. We demonstrated that reovirus induces more than 50% cell death in three
canine mammary gland tumors and one canine malignant melanoma cell line. The
reovirus-induced cell death occurred via the activation of caspase 3. Ras activation has
been shown to be one of the important mechanisms of reovirus-susceptibility in human
cancers. However, Ras activation was not related to the reovirus-susceptibility in canine
solid tumor cell lines, which was similar to reports in canine mast cell tumor and canine
lymphoma. The results of this study highly suggest that canine mammary gland tumor and
canine malignant melanoma are also potential candidates for reovirus therapy in veterinary
oncology. 相似文献
288.
A NOVEL SUPPORT DEVICE FOR HEAD IMMOBILIZATION DURING RADIATION THERAPY THAT IS APPLICABLE TO BOTH CATS AND DOGS
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Yuki Nemoto Takuya Maruo Yasuhiro Fukuyama Shinpei Kawarai Takuo Shida Tomohiro Nakayama 《Veterinary radiology & ultrasound》2015,56(6):680-686
Repeatable head immobilization is important for minimizing positioning error during radiation therapy for veterinary patients with head neoplasms. The purpose of this retrospective cross‐sectional study was to describe a novel technique for head immobilization (Device II) and compare this technique with a previously described technique (Device I). Device II provided additional support by incorporating three teeth (vs. two teeth with Device I). Between 2011 and 2013, both devices were applied in clinically affected cats (Device I, n = 17; Device II, n = 11) and dogs (Device I, n = 85; Device II, n = 22) of various breeds and sizes. The following data were recorded for each included patient: variability in the angle of the skull (roll, yaw, and pitch), coordinates of the isocenter, and distance from the reference mark to the tumor. Devices I and II differed for skull angle variability during the treatment of dogs (roll, P = 0.0007; yaw, P = 0.0018; pitch, P = 0.0384) and for yaw of during the treatment of cats (P < 0.0001). In each case, Device II was superior to Device I. The distance from the reference mark to the center of the tumor was significantly decreased for Device II vs. Device I (dogs, P < 0.0001; cats, P = 0.0002). Device II also provided more accurate coordinates for the isocenter. Authors recommend the use of, Device II for future clinical patients. 相似文献
289.
Kobayashi Y Okuda H Nakamura K Sato G Itou T Carvalho AA Silva MV Mota CS Ito FH Sakai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(11):1145-1154
To investigate the genetic characteristics of phosphoprotein (P) and matrix protein (M) genes of variable rabies virus (RV) prevalent in Brazil, the authors genetically characterized the P and M genes from 30 Brazilian RV field isolates. Phylogenetic analysis based on the P and M genes revealed the presence of six RV variants that consisted primarily of three insectivorous bats, the vampire bat, dog and fox in Brazil. Specific amino acid substitutions corresponding to these phylogenetic lineages were observed, with Asp(42) and Glu(62) in the P protein found to be characteristic of Brazilian chiroptera- and carnivora-related RVs, respectively. Amino acid sequence motifs predicted to associate with a viral function in the P and M proteins were conserved among Brazilian RV variants. 相似文献
290.
Aerodynamically designed surrogate surfaces were used to determine the relative importance of gaseous (SO2, HNO3, NH3) and particulate species (SO4 2?, NO3 ?, NH4 +, Ca2+) in the dry deposition flux. For 11 sampling periods, we measured the deposition fluxes, ambient gaseous concentrations, size distributions of atmospheric aerosols and some meteorological parameters in Uji. The dry deposition of the gas to a nearly perfect sink was calculated by subtracting the greased surface flux from the total deposition flux to both the greased and reagent impregnated (or water) surface. It was found that the gas phase deposition contributed significantly more (60–93%) than the particulate phase to overall deposition of sulfur and nitrogen compounds. The dry deposition velocities of the species were also calculated using the deposition fluxes and the measured ambient concentrations. Comparisons were made between the measured and modeled particulate deposition flux. 相似文献