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991.
992.
Shin Ae Park Na Young Yi Man Bok Jeong Won Tae Kim Se Eun Kim Je Min Chae Kang Moon Seo 《Veterinary ophthalmology》2009,12(4):205-210
Objective To determine the incidence, etiology, and concurrent ophthalmic findings in small breed dogs that presented with cataracts.
Animal studied Five hundred and sixty-one small breed dogs (942 eyes) were presented to the Veterinary Medical Teaching Hospital of Seoul National University between July 2002 and December 2007 with cataract.
Procedure The medical records of small breed dogs with cataract were reviewed. The reason for presentation, cataract duration, bilaterality, breed, gender, age, vision, etiology, stage of cataract development, concurrent ophthalmic findings, IOP, ocular ultrasonography findings, and scotopic electroretinography (ERG) findings were investigated.
Results The most frequently presented breeds were the Miniature/Toy Poodle ( n = 112, 20.0%), Yorkshire Terrier ( n = 110, 19.6%), and Shih Tzu ( n = 95, 16.9%). The Miniature/Toy Poodle showed a significantly higher odds ratio for cataract formation (2.6). The proportion of female cataract patients was significantly higher than that of male cataract patients in the overall population ( P < 0.05). The Miniature/Toy Poodles had significantly higher numbers of females affected with cataract ( P < 0.01). The mean age for cataract formation was 8.3 ± 3.9 years. The mean age at onset in the Miniature/Toy Poodle and Yorkshire Terrier was significantly higher, whereas that in the Miniature Schnauzer group was significantly lower ( P < 0.0001). Clinical signs related to lens induced uveitis had a tendency to increase with cataract progression ( P < 0.05). There were no significant differences in the b-wave amplitude for mixed rod cone response by stage ( P = 0.137).
Conclusions Small breed dogs with cataracts had characteristics with regard to age of onset and gender distribution, depending on the breed. 相似文献
Animal studied Five hundred and sixty-one small breed dogs (942 eyes) were presented to the Veterinary Medical Teaching Hospital of Seoul National University between July 2002 and December 2007 with cataract.
Procedure The medical records of small breed dogs with cataract were reviewed. The reason for presentation, cataract duration, bilaterality, breed, gender, age, vision, etiology, stage of cataract development, concurrent ophthalmic findings, IOP, ocular ultrasonography findings, and scotopic electroretinography (ERG) findings were investigated.
Results The most frequently presented breeds were the Miniature/Toy Poodle ( n = 112, 20.0%), Yorkshire Terrier ( n = 110, 19.6%), and Shih Tzu ( n = 95, 16.9%). The Miniature/Toy Poodle showed a significantly higher odds ratio for cataract formation (2.6). The proportion of female cataract patients was significantly higher than that of male cataract patients in the overall population ( P < 0.05). The Miniature/Toy Poodles had significantly higher numbers of females affected with cataract ( P < 0.01). The mean age for cataract formation was 8.3 ± 3.9 years. The mean age at onset in the Miniature/Toy Poodle and Yorkshire Terrier was significantly higher, whereas that in the Miniature Schnauzer group was significantly lower ( P < 0.0001). Clinical signs related to lens induced uveitis had a tendency to increase with cataract progression ( P < 0.05). There were no significant differences in the b-wave amplitude for mixed rod cone response by stage ( P = 0.137).
Conclusions Small breed dogs with cataracts had characteristics with regard to age of onset and gender distribution, depending on the breed. 相似文献
993.
Lee So Young Kim Eun-Gyeong Park Jae-Ryoung Jang Yoon-Hee Jan Rahmatullah Ryu Taehun Kim Kyung-Min 《Journal of Crop Science and Biotechnology》2021,24(2):221-228
Journal of Crop Science and Biotechnology - Worldwide, grain consumption is increased and grain prices are rising. This has led to a steady increase in the production of highly productive and more... 相似文献
994.
J. P. Suh C. K. Lee J. H. Lee J. J. Kim S. M. Kim Y. C. Cho S. H. Park J. C. Shin Y. G. Kim K. K. Jena 《Euphytica》2012,184(1):101-108
Cold tolerance at the seedling stage of rice is an important phenotypic trait that causes normal plant growth and stable rice
production in temperate regions as well as tropical high-lands in Asia and Africa. In order to find quantitative trait loci
(QTLs)/genes associated with cold tolerance, we constructed a linkage map using 153 recombinant inbred lines (RILs) derived
from a cross between a cold-tolerant temperate japonica cultivar, Geumobyeo, and a cold-sensitive tropical japonica breeding
line, IR66160-121-4-4-2. The RILs were phenotyped for cold tolerance or sensitivity based on the degrees of cold tolerance
as cold tolerance indices at the seedling stage. The seedlings for cold-tolerance/-sensitive traits were scored on the 7th
day of the recovery period at 25°C after cold treatment at 10°C. Two QTLs (qCTS4a and qCTS4b) associated with cold tolerance at the seedling stage were identified on the long and short arms of chromosome 4 with an
LOD score of 2.89 and 2.75, respectively, using composite interval mapping. The QTLs were flanked by simple sequence repeat
(SSR) markers RM3648-RM2799 and RM3375a-RM558 that explained 8.3 and 7.8% of the total phenotypic variation, respectively.
Seven of the selected RILs expressed cold tolerance at both the seedling and reproductive stages. The SSR markers associated
with the QTLs will be useful for tracking favorable QTLs/genes into cold-sensitive elite cultivars and may have potential
for pyramiding different QTLs for the improvement of cold tolerance in rice. 相似文献
995.
BACKGROUND: In the natural environment, photodegradation is one of the most common degradative processes of pesticides. In order to reduce the photodegradation of pesticides, and so increase their killing activity against target pests, chitosan‐coated beeswax solid lipid nanoparticles (CH‐BSLNs) were prepared by a combination of hot homogenization and sonication, with deltamethrin as an active ingredient. RESULTS: Under optimal conditions, the highest encapsulation efficiency (95%) and a high payload of deltamethrin (approximately 12.5%) were achieved. In direct photolysis, in the case of CH‐BSLNs after UV irradiation for 24 h, 37.3% of deltamethrin remained, as opposed to only 14.6% of the free‐form deltamethrin. In addition, in indirect photolysis, in the case of CH‐BSLNs after UV irradiation for 2 h in 2% acetone solution, approximately 74.5% of deltamethrin remained, as opposed to only 37.6% of the free‐form deltamethrin. CONCLUSION: CH‐BSLNs showed good protection for deltamethrin against photodegradation. This novel nanocarrier may be useful in crop protection as an economical strategy to enhance the effect of pesticides in the field and protect the environment as well. Copyright © 2012 Society of Chemical Industry 相似文献
996.
Russell CT Raymond CA Coradini A McSween HY Zuber MT Nathues A De Sanctis MC Jaumann R Konopliv AS Preusker F Asmar SW Park RS Gaskell R Keller HU Mottola S Roatsch T Scully JE Smith DE Tricarico P Toplis MJ Christensen UR Feldman WC Lawrence DJ McCoy TJ Prettyman TH Reedy RC Sykes ME Titus TN 《Science (New York, N.Y.)》2012,336(6082):684-686
The Dawn spacecraft targeted 4 Vesta, believed to be a remnant intact protoplanet from the earliest epoch of solar system formation, based on analyses of howardite-eucrite-diogenite (HED) meteorites that indicate a differentiated parent body. Dawn observations reveal a giant basin at Vesta's south pole, whose excavation was sufficient to produce Vesta-family asteroids (Vestoids) and HED meteorites. The spatially resolved mineralogy of the surface reflects the composition of the HED meteorites, confirming the formation of Vesta's crust by melting of a chondritic parent body. Vesta's mass, volume, and gravitational field are consistent with a core having an average radius of 107 to 113 kilometers, indicating sufficient internal melting to segregate iron. Dawn's results confirm predictions that Vesta differentiated and support its identification as the parent body of the HEDs. 相似文献
997.
Kyoung Ho Kang Hae-Joong Park Young Hun Kim Seung Cheon Seon & Bin Zhou 《Aquaculture Research》2008,39(2):195-199
To investigate the effects of temperature and salinity on filtration and oxygen consumption rate of Scapharca broughtonii spat with different growth stages. This study was conducted under six different water temperatures and five different salinity conditions. The spat were divided into three groups of different shell sizes and filtration rates were estimated by Neutral red. The results showed that in all of the three groups, the highest filtration rates appeared at 20 °C, and the highest one was 1.89±0.12 L g h?1 in the group with the lowest shell length (11.8±2.1 mm). The filtration rates in every group increased with the rise of salinity in the range from 10 to 40 g L?1, and the highest one is 2.62±0.21 L g h?1 in the lowest shell length group. The trends of oxygen consumption rates were similar to filtration rates. The highest rates were 0.189±0.003 mg g h?1 at 20 °C and 0.308±0.018 mg g h?1 at a salinity of 40 g L?1 in the group with the lowest shell length. And the results showed that the smaller the shell size, the higher the filtration and oxygen consumption rate. 相似文献
998.
K S Kang J E Park D Y Ryu Y S Lee 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(11):1183-1190
Endocrine disrupters are exogenous compounds thought to mimic the action of estrogen or other hormones and influence endocrine activity in the body (Juberg, 2000). These chemicals have adverse effects not only in the reproductive system but also in the central nervous system during development and throughout life. Polychlorinated biphenyls (PCBs) are a class of environmentally persistent and widespread halogenated hydrocarbons. It has been reported that PCBs are potential neurotoxicants. Endosulfan is an organochlorine insecticide that is extensively used to control pests in vegetables, cotton, and fruits. To determine the effect of 2, 2', 4, 4', 5, 5',-hexachlorobiphenyl(2, 4, 5-HCB) and endosulfan on embryo nervous system, we isolated neural stem cells from rat brain at embryonic day 17. Isolated neural stem cells showed pluripotenty. Stem cells could differentiate into neurons and glia. Neurite formation in endosulfan and 2, 4, 5-HCB treated cells. And it appeared to be decreased as compared with that in untreated cells. In order to know the neuro-toxic mechanisms of 2, 4, 5-HCB and endosulfan in neuronal stem cells, we investigated mitogen-activated protein kinase activity (MAPK) and gap junctional intercellular communication (GJIC). Endosulfan decreased the MAPK activity in dose dependent manner. Endosulfan and 2, 4, 5-HCB inhibited GJIC compared to the untreated cell by scrape loading dye transfer (SL/DT). 2, 4, 5-HCB and endosulfan decreased the expression of connexin 43 in dose dependent manner. These results indicated that 2, 4, 5-HCB and endosulfan may inhibit differentiation and proliferation of neural stem cells and gap junctional intercellular communication which play a crucial role in the maintenance of cellular homeostasis. 相似文献
999.
To study the origin of unreduced (2n) gametes in diploid Vitis cultivars, we surveyed the occurrence of tetraploid hybrid seedlings from 40 interploid crosses with five tetraploid and
seven diploid cultivars. A total of 250 seedlings from the interploid crosses were established through embryo culture and
by seed sowing. In 20 2x × 4x crosses, no tetraploid hybrid seedlings were derived from 8,902pollinations. In 20 4x × 2x crosses,
two tetraploid hybrid seedlings were obtained from 8,057 pollinations. Investigation of isozyme genotypes of the two tetraploid
seedlings using three variable enzyme systems indicated that one of the two seedlings resulted from the union of a diploid
egg with a 2n male gamete and that failure of second meiotic division resulted in the formation of the 2n male gamete. The
percentage of giant pollen grains in `Muscat Bailey A', a pollen parent of the tetraploid seedling, was relatively high(about
5.9%) and 10.9% of the giant pollen grains germinated on agar medium. These results suggested that 2n pollen of diploid cultivars
are useful for breeding tetraploid grape.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
1000.
Jasmonic Acid Differentially Affects Growth, Ion Uptake and Abscisic Acid Concentration in Salt-tolerant and Salt-sensitive Rice Cultivars 总被引:2,自引:0,他引:2
D.-J. Kang Y.-J. Seo J.-D. Lee R. Ishii K. U. Kim D. H. Shin S. K. Park S. W. Jang I.-J. Lee 《Journal of Agronomy and Crop Science》2005,191(4):273-282
Phytohormones play critical roles in regulating plant responses to stress. Here, we investigated the effects of salt stress and stress recovery by applying jasmonate to the two different rice (Oryza sativa L.) cultivars Dongjinchalbyeo (DJC, salt-tolerant) and Dongjinbyeo (DJ, salt-sensitive). Salt stress remarkably decreased the root length of plants even at low NaCl concentration (20 mm ). Salt stress led to a sharp increase in the concentrations of abscisic acid (ABA) in 20 and 40 mm NaCl, when compared with the control values. The concentrations of ABA in the salt-tolerant cultivar DJC plants progressively increased with increasing NaCl levels, whereas in the salt-sensitive cultivar DJ, they sharply decreased in all three parts of rice plants at 80 mm NaCl treatment. The decrease of jasmonic acid (JA) concentrations in salt-tolerant cultivar DJC was lesser than in the salt-sensitive cultivar DJ plants in the shoot. Post-application in the stressed plants with 30 μm JA at 24 and 48 h after NaCl treatment, recovered salt inhibition on dry mass production more effectively than application of JA at 48 and 24 h before salt stress, and during salt stress simultaneously. The uptake of Na decreased especially in the salt-sensitive cultivar DJ plants, whereas there was an increase in Ca and Mg levels and slight increase of K by JA application. Leaf water potential, leaf photosynthetic rate, and maximum quantum yield of photosystem II (PSII) also remarkably recovered when 30 μm JA was applied 24 h after the salt stress compared with the 40 mm NaCl-treated plants. These results clearly indicate that post-application with exogenous JA can ameliorate salt-stressed rice seedlings, especially the salt-sensitive cultivar rather than the salt-tolerant cultivar. This may change the balance of other endogenous plant hormones. 相似文献