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31.
F.?Ishiguri S.?Maruyama K.?Takahashi Z.?Abe S.?Yokota M.?Andoh N.?YoshizawaEmail author 《Journal of Wood Science》2003,49(2):135-139
Sugi green logs with red or black heartwood were smoke-heated, and the changes in the color of the heartwood after ultraviolet
(UV) (λ = 365 nm) radiation exposure were then observed. After UV radiation exposure, the redness and yellowness increased in both
the red and black heartwoods, whereas the brightness decreased. In the black heartwood, the resulting color turned from yellowish
white to reddish brown. Reddening in black heartwood after exposure to a combination of smoke heating and UV radiation is
thought to be due to a decrease in brightness and an increase in both redness and yellowness. However, the degree of change
in heartwood color by UV radiation exposure was not greatly affected by smoke-heating treatments of various lengths. When
methanol extracts were fractionated and exposed to UV radiation, the yellowness increased in the n-hexane-soluble portion and the redness increased in the acetone-soluble fractions from the n-hexane-insoluble portion. These results suggest that the n-hexane-soluble fraction contains the substances that allow heartwood color to change to yellow after UV radiation exposure,
and the acetone-soluble-fraction from the n-hexane-insoluble portion contains the substances that allow it to change to red.
Received: November 14, 2001 / Accepted: June 3, 2002
Acknowledgment This research was supported in part by a Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of
Science.
This study was presented in part at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001
Correspondence to:N. Yoshizawa 相似文献
32.
Summary The phenyl nucleus-exchange method (NE-method) is a procedure for the degradation of lignin which allows the C–C linkages between the side chains and the phenyl nuclei to be cleaved selectively, and the phenyl nuclei to be liberated finally as polyhydric phenols. The important characteristic of this method is to take advantage of the dealkylation in diphenylmethane type structures in the presence of boron trifluoride and excess phenol, for the degradation of lignin. The lignin building units which give phenol monomers (guaiacol and/or catechol in softwood lignin) almost quantitatively by this method are noncondensed types and diphenylmethane types, and each of these units has any of the benzyl alcohol, the benzyl ether, the conjugated double bond, the -carbonyl group and the C-aryl bond, in the side chain. The yields of phenyl nuclei are about 25–30% in softwood protolignins and about 8–13% in technical lignins. In this paper, the reaction theory and the degradation mechanism of lignins in the NE-method are outlined. 相似文献
33.
This study examined how boiling and drying treatments influenced various physical properties of the tension wood with gelatinous
fibers (G-fibers) of a 29-yearold Zelkova branch. By boiling treatment, tension wood with numerous G-fibers contracted considerably in the longitudinal direction and
the longitudinal Young’s modulus decreased in spite of the water-saturated condition. The drying treatment caused green tension
wood and boiled tension wood with numerous G-fibers to shrink longitudinally and increased their longitudinal Young’s moduli.
These specific behaviors in tension wood were highly correlated with the proportion of G-fibers in a specimen and were probably
caused by the microscopic behavior of cellulose microfibril (CMF) in the gelatinous layers (G-layers). The longitudinal shrinkage
of tension wood due to drying suggests the existence of a hygro-sensible, noncrystalline region in the CMF, which is abundant
in the G-layer. Furthermore, the noncrystalline region in the CMF softens during boiling treatment, resulting in the reduction
of the longitudinal Young’s modulus in tension wood. The longitudinal contraction of tension wood with G-fibers by boiling
might be caused by the tensile growth stress remaining in green G-layers. However, no changes were detected in the 004 d-spacing of cellulose crystal in tension wood from the boiling and drying treatments, regardless of the proportion of G-fibers. 相似文献
34.
Yasuyuki Tachiki Tetsuhiko Yoshimura Hisashi Hasegawa Tomonori Mita Tetsuro Sakai Futoshi Nakamura 《Journal of Forest Research》2005,10(6):419-427
The objectives of this study were to determine Global Positioning System (GPS) positional errors while moving under the forest
canopy and to clarify the effects of polyline simplification on area and perimeter estimations. We used the Pathfinder Pro
XR and GPSMAP 76S, which are categorized as “high-end mapping” and “general navigation” GPS receivers, respectively. The field
tests were conducted in both natural and plantation forests. The results showed that the Pathfinder Pro XR, which has better
multipath rejection technology, worked well, especially in the plantation forest under unfavorable conditions of higher stand
density. We used analysis of variance to clarify the effects of the receiver type, positioning mode, stand type, and polyline
simplification method on area and perimeter estimations. The receiver type and positioning mode were found to be significant
factors that affected area estimation. The Pathfinder Pro XR estimated the area more accurately than the GPSMAP 76S, and differential
GPS estimated the area more accurately than autonomous GPS. With respect to the perimeter, the receiver type, positioning
mode, and polyline simplification method were found to be significant factors. The results showed that perimeter estimation
was improved by using the velocity filter, and further improved by using the velocity filter and Douglas-Peucker algorithm,
especially when the Pathfinder Pro XR was used. The GPSMAP 76S estimated the perimeter accurately without any filtering because
its default speed filter worked well, even though the GPSMAP 76S is a general navigation GPS receiver. 相似文献
35.
Application of cationic polymer prepared from sulfuric acid lignin as a retention aid for usual rosin sizes to neutral papermaking 总被引:3,自引:0,他引:3
Yasuyuki?MatsushitaEmail author Ayuko?Iwatsuki Seiichi?Yasuda 《Journal of Wood Science》2004,50(6):540-544
Cationic polymers that acted as the retention aids for usual rosin sizes in neutral papermaking were prepared from sulfuric acid lignin (SAL), one type of acid lignin. To convert SAL to the cationic polymer (MP-SAL), SAL was phenolated and then treated by the Mannich reaction to introduce the amino groups. In the MP-SAL single system, MP-SAL exhibited high sizing effectiveness in neutral papermaking with the rosin emulsion size. However, MP-SAL showed no sizing effectiveness when soap rosin size was used. MP-SAL showed increased sizing effectiveness as the pK
a of the introduced amino group increased. From this and comparison of the sizing degrees of MP-SAL and polyethylenimine, which possesses a linear structure, it was suggested that the sizing effectiveness was not only affected by the charge density and molecular weight, but also by the basicity of the introduced amino groups and the molecular structure of the retention aid. In the alum–MP-SAL dual system, alum and MP-SAL synergistically enhanced the sizing effectiveness in the rosin emulsion sizing at neutral pH. In turn, this allowed a decrease in the MP-SAL dosage and resulted in a small decrease in brightness.Part of this report was presented at the 48th Lignin Symposium, October 2003, Fukui 相似文献
36.
Kazuya KUSHIDA Urs GIGER Toshihiko TSUTSUI Megumi INABA Yoshio KONNO Kureha HAYASHI Kana NOGUCHI Akira YABUKI Keijiro MIZUKAMI Moeko KOHYAMA Yasuyuki ENDO Osamu YAMATO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(6):743-746
Erythrocyte pyruvate kinase (PK) deficiency is an inherited glycolytic erythroenzymopathy
caused by mutations of the PKLR gene. A causative mutation of the feline
PKLR gene was originally identified in Abyssinian and Somali cats in
the U.S.A. In the present study, a TaqMan probe-based real-time PCR genotyping assay was
developed and evaluated for rapid genotyping and large-scale screening for this mutation.
Furthermore, a genotyping survey was carried out in a population of four popular purebred
cats in Japan to determine the current mutant allele frequency. The assay clearly
displayed all genotypes of feline PK deficiency, indicating its suitability for
large-scale survey as well as diagnosis. The survey demonstrated that the mutant allele
frequency in Abyssinian and Somali cats was high enough to warrant measures to control and
prevent the disease. The mutant allele frequency was relatively low in Bengal and American
Shorthair cats; however, the testing should still be carried out to prevent the spread of
the disease. In addition, PK deficiency should always be considered in the differential
diagnosis of anemia in purebred cats in Japan as well as worldwide. 相似文献
37.
Shotaro KUBO Morihiro TATENO Yasuaki ICHIKAWA Yasuyuki ENDO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1275-1279
Tick-borne diseases are often encountered in canine clinical practice. In the present
study, a molecular epidemiological survey of dogs in Japan was conducted to understand the
prevalence and geographical distribution of Babesia spp.,
Hepatozoon spp., Ehrlichia spp. and
Anaplasma spp. Pathogen-derived DNA in blood samples obtained from 722
dogs with a history of exposure to ticks and/or fleas was examined by PCR. The prevalence
of Babesia gibsoni, Babesia odocoilei-like species,
Hepatozoon canis and Ehrlichia
spp./Anaplasma spp. was 2.4% (16/722), 0.1% (1/722), 2.5% (18/722) and
1.5% (11/722), respectively. While B. gibsoni and
Ehrlichia spp./Anaplasma spp. were detected in the
western part of Japan, H. canis was detected in Tohoku area in addition
to western and central parts of Japan. 相似文献
38.
Assessing the influence of mechanical ventilation on blood gases and blood pressure in rattlesnakes
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Mads F Bertelsen Rasmus Buchanan Heidi M Jensen Cleo AC Leite Augusto S Abe Søren S Nielsen Tobias Wang 《Veterinary anaesthesia and analgesia》2015,42(4):386-393
ObjectiveTo characterize the impact of mechanical positive pressure ventilation on heart rate (HR), arterial blood pressure, blood gases, lactate, glucose, sodium, potassium and calcium concentrations in rattlesnakes during anesthesia and the subsequent recovery period.Study designProspective, randomized trial.AnimalsTwenty one fasted adult South American rattlesnakes (Crotalus durissus terrificus).MethodsSnakes were anesthetized with propofol (15 mg kg−1) intravenously, endotracheally intubated and assigned to one of four ventilation regimens: Spontaneous ventilation, or mechanical ventilation at a tidal volume of 30 mL kg−1 at 1 breath every 90 seconds, 5 breaths minute−1, or 15 breaths minute−1. Arterial blood was collected from indwelling catheters at 30, 40, and 60 minutes and 2, 6, and 24 hours following induction of anesthesia and analyzed for pH, PaO2, PaCO2, and selected variables. Mean arterial blood pressure (MAP) and HR were recorded at 30, 40, 60 minutes and 24 hours.ResultsSpontaneous ventilation and 1 breath every 90 seconds resulted in a mild hypercapnia (PaCO2 22.4 ± 4.3 mmHg [3.0 ± 0.6 kPa] and 24.5 ± 1.6 mmHg [3.3 ± 0.2 kPa], respectively), 5 breaths minute−1 resulted in normocapnia (14.2 ± 2.7 mmHg [1.9 ± 0.4 kPa]), while 15 breaths minute−1 caused marked hypocapnia (8.2 ± 2.5 mmHg [1.1 ± 0.3 kPa]). Following recovery, blood gases of the four groups were similar from 2 hours. Anesthesia, independent of ventilation was associated with significantly elevated glucose, lactate and potassium concentrations compared to values at 24 hours (p < 0.0001). MAP increased significantly with increasing ventilation frequency (p < 0.001). HR did not vary among regimens.Conclusions and clinical relevanceMechanical ventilation had a profound impact on blood gases and blood pressure. The results support the use of mechanical ventilation with a frequency of 1–2 breaths minute−1 at a tidal volume of 30 mL kg−1 during anesthesia in fasted snakes. 相似文献
39.
40.
Azusa SOMEYA Ryoko FUKUSHIMA Michiko YOSHIDA Yasuyuki TANAHASHI Tangmunkhong PRAPEUK Reiko IIZUKA Hiroshi HIRAMI Atsushi MATSUDA Shunichi TAKAHASHI Goro KURITA Takashi KIMURA Misuzu SEO Masayuki FUNABA Yoshii NISHINO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2014,76(8):1157-1160