西南矮马矮小性状基因SHOX的克隆测序和多态性研究

本研究首次克隆出西南马矮小性状基因完整第二外显子序列,GenBank登录号为EU556739;通过PCR-SSCP方法对8个品种150匹马的该序列做了多态性分析,在P2位点上268处有1个G→A的突变,和431处有1个T→G的突变导致了等位基因B变为等位基因A.该位点除云南文山马(WS)的优势基因型和优势等位基因分别为AB型和B外,其余类群马均为BB型和B.云南丘北马(QB)、云南文山马(WS)、云南大理马(DL)、建昌马(JC)和设特兰马(ST)在P2位点上处于Hardy-Weinberg平衡状态.     

Acute idiopathic polyneuropathy in the dog

From among a large group of dogs with acute tetraparesis, we identified 10 dogs with a distinct peripheral nerve disorder. Prior to the onset of signs, all of the dogs had been healthy, and none was known to have been exposed to a neurotoxin or raccoon bite. Weakness, with hypoactive or absent segmental reflexes, became progressively worse for 1 to 21 days. Results of electromyography and nerve conduction studies invariably were compatible with a diagnosis of polyneuropathy that predominantly affected proximal nerve segments. Appearance of nerve biopsy specimens and the short time course for functional recovery suggested a demyelinative component to the disorder. The extent of recovery was variable but often rapid and complete in dogs that did not succumb to complications in the early period. Corticosteroid therapy did not demonstrably influence the outcome. This acute idiopathic polyneuropathy in the dog shares many clinical and pathologic features with idiopathic polyradiculoneuritis (Coonhound paralysis).     

Use of anti-coronavirus antibody testing of cerebrospinal fluid for diagnosis of feline infectious peritonitis involving the central nervous system in cats

OBJECTIVE: To assess the use of measuring anti-coronavirus IgG in CSF for the diagnosis of feline infectious peritonitis (FIP) involving the CNS in cats. DESIGN: Prospective study. SAMPLE POPULATION: CSF and serum samples from 67 cats. PROCEDURES: CSF and serum samples were allocated into 4 groups: cats with FIP involving the CNS (n = 10), cats with FIP not involving the CNS (13), cats with CNS disorders caused by diseases other than FIP (29), and cats with diseases other than FIP and not involving the CNS (15). Cerebrospinal fluid was evaluated for concentrations of erythrocytes, leukocytes, and total protein. Anti-coronavirus IgG was measured in CSF and serum by indirect immunofluorescence assay. RESULTS: CSF IgG (range of titers, 1:32 to 1:4,096) was detected in 12 cats, including 6 cats with neurologic manifestation of FIP, 4 cats with FIP not involving the CNS, and 2 cats with brain tumors. Cerebrospinal fluid IgG was detected only in cats with correspondingly high serum IgG titers (range, 1:4,096 to 1:16,384) and was positively correlated with serum IgG titers (r = 0.652; P < 0.01), but not with any other CSF parameter. Blood contamination of CSF resulted in < or = 333 erythrocytes/microL in cats with CSF IgG. CONCLUSIONS AND CLINICAL RELEVANCE: The correlation between serum and CSF IgG and the fact that CSF IgG was detected only in strongly seropositive cats suggested that CSF anti-coronavirus IgG was derived from blood. Measurement of anti-coronavirus IgG in CSF was of equivocal clinical use.     

Plasma diagnosis from thermal noise and limits on dust flux or mass in comet giacobini-zinner

Thermal noise spectroscopy was used to measure the density and temperature of the main (cold) electron plasma population during 2 hours (1.5x10(5) kilometers perpendicular to the tail axis) around the point of closest approach of the International Cometary Explorer (ICE) to Comet Giacobini-Zinner. The time resolution was 18 seconds (370 kilometers) in the plasma tail and 54 seconds (1100 kilometers) elsewhere. Near the tail axis, the maximum plasma density was 670 per cubic centimeter and the temperature slightly above 1 electron volt. Away from the axis, the plasma density dropped to 100 per cubic centimeter (temperature, 2x 10(4) K) over 2000 kilometers, then decreased to 10 (1.5x 10(5)K) over 15,000 kilometers; outside that region (plasma tail), the density fluctuated between 10 and 30 per cubic centimeter and the temperature between 1x 10(5) and 4 x10(5) K. The relative density of the hot population rarely exceeded a few percent. The tail was highly asymmetrical and showed much structure. On the other antenna, shot noise was recorded from the plasma particle impacts on the spacecraft body. No evidence was found of grain impacts on the antennas or spacecraft in the plasma tail. This yields an upper limit for the dust flux or particle mass, indicating either fluxes or masses in the tail smaller than implied by the models or an anomalous grain structure. This seems to support earlier suggestions that these grains are featherlike. Outside the tail, and particularly near 10(5) kilometers from its axis, impulsive noises indicating plasma turbulence were observed.     

Plasma observations near neptune: initial results from voyager 2

The plasma science experiment on Voyager 2 made observations of the plasma environment in Neptune's magnetosphere and in the surrounding solar wind. Because of the large tilt of the magnetic dipole and fortuitous timing, Voyager entered Neptune's magnetosphere through the cusp region, the first cusp observations at an outer planet. Thus the transition from the magnetosheath to the magnetosphere observed by Voyager 2 was not sharp but rather appeared as a gradual decrease in plasma density and temperature. The maximum plasma density observed in the magnetosphere is inferred to be 1.4 per cubic centimeter (the exact value depends on the composition), the smallest observed by Voyager in any magnetosphere. The plasma has at least two components; light ions (mass, 1 to 5) and heavy ions (mass, 10 to 40), but more precise species identification is not yet available. Most of the plasma is concentrated in a plasma sheet or plasma torus and near closest approach to the planet. A likely source of the heavy ions is Triton's atmosphere or ionosphere, whereas the light ions probably escape from Neptune. The large tilt of Neptune's magnetic dipole produces a dynamic magnetosphere that changes configuration every 16 hours as the planet rotates.     

日粮中添加不同锰、锌源对肉鸡生长性能及免疫机能的影响

将216只1日龄健康艾维茵肉鸡随机分为4个处理组,试验期7周。处理组日粮分别在锰含量为37.66mg/kg、锌含量为21.87mg/kg的基础日粮中添加不同的锰源与不同的锌源,其中处理1组为无机锰 无机锌,处理2组为有机锰 无机锌,处理3组为无机锰 有机锰 无机锌,处理4组为无机锰 有机锰 无机锌 有机锌,研究不同锰、锌源对肉鸡生长性能及免疫机能的影响。结果表明,氨基酸螯合锰部分或全部替代日粮中的无机锰,肉鸡生长速度及饲料转化效率有增加的趋势,氨基酸螯合锰、锌同时替代无机锰、锌,肉鸡的生长速度显著增加(p<0.05),饲料转化率也有增加的趋势。氨基酸螯合锰、锌与无机锰、锌相比,有促进机体免疫机能的趋势。     

Cause and duration of mustard incorporation effects on soil-borne plant pathogenic fungi

Two fungal plant pathogens, Rhizoctonia solani AG 2-2 and Fusarium oxysporum f.sp. lini, were studied in relation to general responses of soil fungi and bacteria following incorporation of Brassica juncea. Our aim was to understand to what extent the changes in the biological and physicochemical characteristics of the soil could explain the effects on the studied pathogens and diseases, and to determine the temporal nature of the responses. Short-term effects of mustard incorporation (up to 4 months) were investigated in a microcosm experiment, and compared with a treatment where composted plant material was incorporated. In a field experiment, the responses were followed up to 11 months after removal or incorporation of a mustard crop. In general, responses in the variables measured changed more after incorporation of fresh mustard material than after addition of similar amounts of composted plant material (microcosms) or after removal of the mustard crop (field). The soil inoculum potential of R. solani AG 2-2 decreased directly after incorporation of mustard, but increased later to disease levels above those in the untreated soil. Neither of these effects could be explained by changes in the population density of R. solani AG 2-2. Fusarium spp. were less influenced, although an increase in the suppressiveness to Fusarium wilt was observed after mustard incorporation as compared with the treatment where mustard was removed. The microbial responses to mustard incorporation were more pronounced for bacteria than for fungi. After an initial substantial increase, the bacterial density decreased but remained above the levels in the control treatment throughout the experimental periods. The bacterial community structure was modified up to 8 months after mustard incorporation. We conclude that incorporation of fresh mustard influences soil microbial communities, especially the bacteria, and has a potential to control the pathogenic activity of R. solani 2-2 on a short-term perspective. The time dependency in microbial responses is important and should be taken into consideration for the evaluation of the potential of Brassicas to control plant disease on a field scale.