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草原的生物多样性   总被引:1,自引:0,他引:1  
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(1) 使用电熨斗前应用试电笔检查其外壳是否漏电 ,若漏电应维修后再用。(2 ) 电源线为三芯的应使插头的接地芯与插座的接地芯相对应 ,不可错接使用。(3) 电熨斗最好不要与其它大功率电器同时使用。(4) 普通型电熨斗不宜长时间带电 ,在熨烫过程中要掌握好温度 ,及时插拔电源插头。(5) 使用期间需短暂间歇时 ,将电熨斗竖立放置或放在专用的支架上 ,以免引起火灾。(6 ) 使用调温电熨斗应根据不同的面料调整相应的温度点。停用后应将温控器调节钮调到“关”或“断”的位置。(7) 使用蒸汽喷雾电熨斗应加入适量的纯净水或蒸馏水以防结水垢…  相似文献   
4.
OBJECTIVE: To evaluate the efficacy of an inactivated bovine herpesvirus-1 (BHV-1) vaccine to protect against BHV-1 challenge-induced abortion and stillbirth. DESIGN: Prospective study. ANIMALS: 35 beef heifers. PROCEDURES: Before breeding, heifers were vaccinated with a commercially available BHV-1 inactivated vaccine SC or IM. The estrous cycle was then synchronized, and heifers were artificially inseminated 30 to 60 days after vaccination. Heifers (n = 21) were challenge inoculated IV at approximately 180 days of gestation with virulent BHV-1. Fourteen control heifers were not vaccinated. Clinical signs of BHV-1 infection were monitored for 10 days following challenge; serologic status and occurrence of abortion or stillbirth were evaluated until time of calving. RESULTS: 18 of 21 (85.7%) heifers that received vaccine were protected from abortion following challenge, whereas all 14 control heifers aborted. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that an inactivated BHV-1 vaccine can protect against abortion resulting from a substantial challenge infection, with efficacy similar to that of modified-live BHV-1 vaccines.  相似文献   
5.
在水温7.0~19.5℃和盐度28.7~30.9的养殖环境下,将仿刺参(Apostichopus japonicus)和海黍子(Sargassum muticum)混养在1 m3水体中,研究在一定养殖空间内刺参-海黍子适宜的养殖容量和密度及其对水质的影响。仿刺参平均湿重(25.2±1.21)g;养殖密度,A1~A3组:600 g/m3,B4~B6组:400 g/m3,C7~C9组:200 g/m3。海黍子养殖密度,A1、B4、C7组:0 g/m3,A2、B5、C8组:1 000 g/m3,A3、B6、C9组:2 000g/m3。结果显示:(1)A1、B4组仿刺参的平均日增重率(Mdwg)和特定生长率(SGR)最小;C8和C9组仿刺参的Mdwg和SGR最大;A2组海黍子的SGR最大;C9组海黍子SGR最小;(2)A1、B4组NH4+-N、NO2--N、NO3--N和PO43--P含量较高;A3、B6、C9组各营养因子含量较低。研究表明:海黍子能吸收水体中的营养因子,其密度显著影响仿刺参的生长(P0.05)。本试验条件下,C8、C9组搭配比较合适,生态互利效果最好。  相似文献   
6.
以新鲜浒苔、小黄花鱼为主要原料,研究了原料预处理、调味炒制等工艺条件对浒苔鱼松产品的影响。通过正交设计和感官评定,确定小黄花鱼调味料最佳配方为:食盐3.0%,味精0.8%,白糖2.0%,料酒1.0%;小黄花鱼打浆时间4min;应用响应面分析法得到最优生产工艺:小黄花鱼糜、浒苔粉添加量之比为3.85:1,初炒时间14.2min,炒酥时间41.5min。研制出的鱼松风味独特,营养丰富,为二者资源的深加工开辟了一条新的途径。  相似文献   
7.
In vitro and in vivo studies of the health and nutritional properties of durian (Durio zibethinus Murr.) were compared with snake fruit (Salacca edulis Reinw.) and mangosteen (Garcinia mangostana). Dietary fibers, minerals, and trace metals were comparable. Total polyphenols (mg of GAE/100 g of FW) and flavonoids (85.1+/-6.1) were significantly higher (p<0.05) than in snake fruit (217.1+/-13.2 (mg of CE/100 g of FW)), durian (309.7+/-19.3 and 61.2+/-4.9), and mangosteen (190.3+/-12.1 and 54.1+/-3.8). Antioxidant activity (microM TE/100 g of FW) of durian measured by DPPH and ABTS assays (228.2+/-13.4 and 2016.3+/-81.1) was significantly higher (p<0.05) than in snake fruit (110.4+/-7.9 and 1507.5+/-70.1) and mangosteen (79.1+/-5.9 and 1268.6+/-62.3). HPLC/DAD analysis of durian (microg/100 g of FW) showed that quercetin (1214.23+/-116.7) was present at levels three times that of caffeic acid, and twice as high as p-coumaric and cinnamic acids. The correlation coefficients between the bioactive compounds of fruits and their antioxidant activities were high (R2=0.99). Male Wistar rats (25) were divided into five dietary groups: the control group was fed the basal diet (BD); in addition to BD, the cholesterol (Chol) group was supplemented with 1% of Chol; the diets of the Chol/Durian, Chol/Snake, and Chol/Mangosteen groups were supplemanted with 5% of these fruits, respectively. It was found that diets supplemented with durian, and to a lesser degree with snake fruit and mangosteen, significantly hindered the rise in plasma lipids and the decrease in antioxidant activity. The nutritional values were comparably high. In conclusion, it could be suggested that inclusion of studied tropical fruits, especially durian, in known disease-preventing diets could be beneficial.  相似文献   
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The initial lung lesions in two calves intrabronchially inoculated with Haemophilus somnus are described. The animals were euthanized within 7 h after challenge. The in situ location of H. somnus and accompanying lesions were examined by light microscopy, immunohistochemistry and transmission electron microscopy (TEM). Inoculation with H. somnus resulted in the development of acute pulmonary lesions within 3.5 h. H. somnus antigen was demonstrated only within the luminal spaces of the airways and in one area of bronchio-associated lymphoid tissue (BALT). As observed by TEM, the bacteria were phagocytized by both neutrophils and alveolar macrophages. Antigen was never demonstrated in the pulmonary intravascular macrophages.  相似文献   
10.
Two privately owned domestic rabbits (Oryctolagus cuniculus) in Maryland were found to be infected with the raccoon variant of the rabies virus in 1998. Both rabbits had an acute onset of anorexia and paralysis or paresis of the left forelimb; 1 also developed head tremors and a head tilt. One of the rabbits became ill 25 days after being attacked by a raccoon (Procyon lotor) and was euthanatized 3 days after onset of illness. The other rabbit, which was housed in an outdoor hutch, died 4 days after onset of clinical signs; the source of infection in that rabbit remains unknown. Currently, there is not a rabies vaccine approved for use in rabbits; thus, the only way to prevent the infection in rabbits is to prevent exposure. Veterinarians in rabies-enzootic areas should be familiar with the clinical signs of rabies in rabbits and should caution rabbit owners about the need to protect their pets from contact with wildlife.  相似文献   
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