全文获取类型
收费全文 | 173篇 |
免费 | 4篇 |
专业分类
林业 | 9篇 |
农学 | 4篇 |
基础科学 | 2篇 |
27篇 | |
综合类 | 15篇 |
农作物 | 2篇 |
水产渔业 | 21篇 |
畜牧兽医 | 88篇 |
园艺 | 1篇 |
植物保护 | 8篇 |
出版年
2022年 | 1篇 |
2021年 | 12篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 3篇 |
2015年 | 9篇 |
2014年 | 12篇 |
2013年 | 9篇 |
2012年 | 4篇 |
2011年 | 11篇 |
2010年 | 6篇 |
2009年 | 9篇 |
2008年 | 5篇 |
2007年 | 8篇 |
2006年 | 16篇 |
2005年 | 9篇 |
2004年 | 9篇 |
2003年 | 6篇 |
2002年 | 3篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 5篇 |
1995年 | 1篇 |
1992年 | 3篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1985年 | 3篇 |
1982年 | 1篇 |
1980年 | 1篇 |
1974年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1960年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有177条查询结果,搜索用时 389 毫秒
1.
ABSTRACT Effect of temperature on leaf colonization in anthurium blight was studied using a bioluminescent strain of Xanthomonas campestris pv. dieffenbachiae. In a susceptible cultivar, colonization of leaf tissues (monitored by detection of bioluminescence) and symptom development (assessed visually) advanced rapidly at higher temperatures. For a susceptible cultivar, there was a linear relationship between degree-days and percent leaf area colonized by the pathogen, indicating that leaf colonization in a susceptible cultivar was a direct function of the cumulative effect of temperature. The degree-day intercept of the regression line represented the time from inoculation to detection of bioluminescence, and the slope indicated the increase of leaf colonization per degree-day. There also was a linear relationship between the logarithm of degree-days and the logarithm of percent leaf area showing visible symptoms in a susceptible cultivar. The degree-day intercept of this relationship represented the incubation period (about 500 degree-days). The degree-days required to detect bioluminescence was not considerably different between susceptible and resistant cultivars. However, the subsequent rates of leaf colonization were significantly lower for a resistant cultivar than for a susceptible cultivar in all temperature regimes. The results suggest that multiplication of the pathogen in the leaf tissues is optimized in the susceptible cultivar. In contrast, in the resistant cultivar, the defense mechanisms overshadow the temperature effect. The differential response to temperatures may be an additional indicator of cultivar susceptibility. 相似文献
2.
A principal nuclear transfer procedure is to inject a donor cell into the perivitelline space in an enucleated oocyte and then electric fusion is performed (cell fusion method). The effects of activation methods in reconstructed oocytes for the serum-starved somatic cell cloning procedure were investigated in this study by means of intracytoplasmic injection (i.c.i.). Bovine oocytes were enucleated at 18-22 h for in vitro maturation, and subsequently the nucleus of cumulus cell collected from Japanese Black Bulls (JBCC) after 5-7 days of starved culture was injected into the recipient cytoplast with a piezo-micromanipulator. At 1 h after i.c.i., reconstructed oocytes were stimulated with ethanol (ET) or calcium ionophore (CaI) as the first activation treatment, followed by cycloheximide (CHX) or 6-dimethylaminopurin (DMAP) treatment as the second activation. In the experiment on the first activation method, the proportion of reconstructed oocytes developing to the blastocyst stage was significantly (p<0.01) higher in the ET activation method than that with CaI (10.5% and 4.7%, respectively). And the experiment on the second activation method after ET treatment showed similar proportions of blastocyst development in both CHX and DMAP treatments (5.9% and 2.8%, respectively). The present results indicated that combined activation treatment with ET and CHX was efficient for reconstructed bovine oocytes by i.c.i. 相似文献
3.
Jun TAMURA Tomohito ISHIZUKA Sho FUKUI Norihiko OYAMA Kodai KAWASE Kenjiro MIYOSHI Tadashi SANO Kirby PASLOSKE Kazuto YAMASHITA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(3):289-296
The pharmacological effects of the anesthetic alfaxalone were evaluated after
intramuscular (IM) administration to 6 healthy beagle dogs. The dogs received three IM
doses each of alfaxalone at increasing dose rates of 5 mg/kg (IM5), 7.5 mg/kg (IM7.5) and
10 mg/kg (IM10) every other day. Anesthetic effect was subjectively
evaluated by using an ordinal scoring system to determine the degree of neuro-depression
and the quality of anesthetic induction and recovery from anesthesia. Cardiorespiratory
variables were measured using noninvasive methods. Alfaxalone administered IM produced
dose-dependent neuro-depression and lateral recumbency (i.e., 36 ± 28 min, 87 ± 26 min and
115 ± 29 min after the IM5, IM7.5 and IM10 treatments, respectively). The endotracheal
tube was tolerated in all dogs for 46 ± 20 and 58 ± 21 min after the IM7.5 and IM10
treatments, respectively. It was not possible to place endotracheal tubes in 5 of the
6 dogs after the IM5 treatment. Most cardiorespiratory variables remained
within clinically acceptable ranges, but hypoxemia was observed by pulse oximetry for 5 to
10 min in 2 dogs receiving the IM10 treatment. Dose-dependent decreases in rectal
temperature, respiratory rate and arterial blood pressure also occurred. The quality of
recovery was considered satisfactory in all dogs receiving each treatment; all the dog
exhibited transient muscular tremors and staggering gait. In conclusion, IM alfaxalone
produced a dose-dependent anesthetic effect with relatively mild cardiorespiratory
depression in dogs. However, hypoxemia may occur at higher IM doses of alfaxalone. 相似文献
4.
Jun TAMURA Takaharu ITAMI Tomohito ISHIZUKA Sho FUKUI Kenjirou MIYOSHI Tadashi SANO Kazuto YAMASHITA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(7):865-869
To determine the reference level of central venous oxygen saturation (ScvO2)
and clinical efficacy of central venous blood gas analysis, partial pressures of oxygen
and carbon dioxide, pH, oxygen saturation, base excess (B.E.) and HCO3
concentration were compared between simultaneously obtained central venous and arterial
blood samples from conscious healthy 6 dogs and 5 cats. Comparisons between arteriovenous
samples were performed by a paired t-test and Bland-Altman analysis.
Between arteriovenous samples, B.E. showed good agreement, but there were significant
differences in other parameters in the dogs, and no good agreement was detected in cats.
The ScvO2 in dogs and cats were 82.3 ± 3.5 and 62.4 ± 13.5%, respectively.
Central venous blood gas analysis is indispensable, especially in cats. 相似文献
5.
6.
7.
Fleischer RL Price PB Walker RM Filz RC Fukui K Friedlander MW Holeman E Rajan RS Tamhane AS 《Science (New York, N.Y.)》1967,155(3759):187-189
Cosmic ray nuclei have been observed with the use of plastic trackdetecting solids in satellites and high-altitude balloon flights. Nuclear emulsions in the stacks of plastic sheets allowed the positive identification of cosmic raynuclei as light as nitrogen. The most striking new information was the failure to observe relativistic iron nuclei, a result which has led to an advance in the understanding of track registration criteria. 相似文献
8.
Nakayama T Yonekura-Sakakibara K Sato T Kikuchi S Fukui Y Fukuchi-Mizutani M Ueda T Nakao M Tanaka Y Kusumi T Nishino T 《Science (New York, N.Y.)》2000,290(5494):1163-1166
Aurones are plant flavonoids that provide yellow color to the flowers of some popular ornamental plants, such as snapdragon and cosmos. In this study, we have identified an enzyme responsible for the synthesis of aurone from chalcones in the yellow snapdragon flower. The enzyme (aureusidin synthase) is a 39-kilodalton, copper-containing glycoprotein catalyzing the hydroxylation and/or oxidative cyclization of the precursor chalcones, 2',4',6',4-tetrahydroxychalcone and 2',4',6',3,4-pentahydroxychalcone. The complementary DNA encoding aureusidin synthase is expressed in the petals of aurone-containing varieties. DNA sequence analysis revealed that aureusidin synthase belongs to the plant polyphenol oxidase family, providing an unequivocal example of the function of the polyphenol oxidase homolog in plants, i.e., flower coloration. 相似文献
9.
Gaudi BS Bennett DP Udalski A Gould A Christie GW Maoz D Dong S McCormick J Szymanski MK Tristram PJ Nikolaev S Paczynski B Kubiak M Pietrzynski G Soszynski I Szewczyk O Ulaczyk K Wyrzykowski L;OGLE Collaboration Depoy DL Han C Kaspi S Lee CU Mallia F Natusch T Pogge RW Park BG;MuFUN Collaboration Abe F Bond IA Botzler CS Fukui A Hearnshaw JB Itow Y Kamiya K Korpela AV Kilmartin PM Lin W Masuda K Matsubara Y Motomura M Muraki Y Nakamura S Okumura T Ohnishi K Rattenbury NJ Sako T Saito T Sato S 《Science (New York, N.Y.)》2008,319(5865):927-930
Searches for extrasolar planets have uncovered an astonishing diversity of planetary systems, yet the frequency of solar system analogs remains unknown. The gravitational microlensing planet search method is potentially sensitive to multiple-planet systems containing analogs of all the solar system planets except Mercury. We report the detection of a multiple-planet system with microlensing. We identify two planets with masses of approximately 0.71 and approximately 0.27 times the mass of Jupiter and orbital separations of approximately 2.3 and approximately 4.6 astronomical units orbiting a primary star of mass approximately 0.50 solar mass at a distance of approximately 1.5 kiloparsecs. This system resembles a scaled version of our solar system in that the mass ratio, separation ratio, and equilibrium temperatures of the planets are similar to those of Jupiter and Saturn. These planets could not have been detected with other techniques; their discovery from only six confirmed microlensing planet detections suggests that solar system analogs may be common. 相似文献
10.
Nakai M Fukui Y Asami S Toyoda-Ono Y Iwashita T Shibata H Mitsunaga T Hashimoto F Kiso Y 《Journal of agricultural and food chemistry》2005,53(11):4593-4598
Fifty-four polyphenols isolated from tea leaves were evaluated for their inhibitory activities against pancreatic lipase, the key enzyme of lipid absorption in the gut. (-)-Epigallocatechin 3-O-gallate (EGCG), which is one of major polyphenols in green tea, showed lipase inhibition with an IC50 of 0.349 microM. Moreover, flavan-3-ol digallate esters, such as (-)-epigallocatechin-3,5-digallate, showed higher activities of inhibition on lipase with an IC50 of 0.098 microM. On the other hand, nonesterified flavan-3-ols, such as (+)-catechin, (-)-epicatechin, (+)-gallocatechin, and (-)-epigallocatechin, showed zero and/or the lowest activities against pancreatic lipase (IC50 > 20 microM). These data suggested that the presence of galloyl moieties within the structure was required for enhancement of pancreatic lipase inhibition. It is well-known that flavan-3-ols are polymerized by polyphenol oxidase and/or heating in a manufacturing process of oolong tea. Oolonghomobisflavans A and B and oolongtheanin 3'-O-gallate, which are typical in oolong tea leaves, showed strong inhibitory activities with IC50 values of 0.048, 0.108, and 0.068 microM, respectively, even higher than that of EGCG. The oolong tea polymerized polyphenols (OTPP) were prepared for the assay from oolong tea extract, from which the preparation effectively subtracted the zero and/or less-active monomeric flavan-3-ols by preparative high-performance liquid chromatography. The weight-average molecular weight (Mw) and number-average molecular-weight (Mn) values of OTPP were 2017 and 903, respectively, by using gel permeation choromatography. OTPP showed a 5-fold stronger inhibition against pancreatic lipase (IC50 = 0.28 microg/mL) by comparison with that of the tannase-treated OTPP (IC50 = 1.38 microg/mL). These data suggested that the presence of galloyl moieties within their chemical structures and/or the polymerization of flavan-3-ols were required for enhancement of pancreatic lipase inhibition. 相似文献