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71.
湖南省果梅品种资源种质杂化状况的初步研究   总被引:8,自引:0,他引:8  
刘连森  贺善文 《园艺学报》1993,20(3):225-230
  相似文献   
72.
将红檬实生苗培养于改良无土基质中,接种泡囊-丛枝菌根Glomuscitrocolum,以不接种菌根为对照,并分别施用含氮量相等的3种氮肥,即硝酸按(NO3-N)、尿素(NH2-N)和硫酸铵(NH4-N)。接种菌根16周后,施不同氮肥的红檬实生苗均有效地感染了菌根,并促进了植株的生长。试验证明,红实生苗施硝态氮(NO3-N)使植株的菌根依赖性有明显提高。  相似文献   
73.
In a dose response study in foxes, the median protective dose of ERA BHK21 vaccine in a blister pack bait was 10(6.0) tissue culture infective doses (TCID)/mL, while artificially aged baits with titers of 10(6.3) TCID/mL induced seroconversion in 78% of foxes. There was no significant difference in the development of antibodies in foxes receiving 1, 2 or 3 mL volumes of vaccine in the bait. When baits were exposed to the elements and fed to foxes over a 21 day period, 85% of the animals seroconverted. Age, sex and the way in which the vaccine container was contacted did not appear to be factors in the responses of these animals. Juvenile foxes, approximately six months of age, were marked more readily with the tetracycline bait marker than older animals. Approximately 25% of foxes did not appear to respond well to vaccination and the titer of the vaccine was a critical factor in producing seroconversion in these animals.  相似文献   
74.
Electromyography (EMG) was used to detect myotonic discharges in Quarter Horse breeding stock and to follow the results of mating horses with hyperkalemic periodic paralysis (HPP). The studies were performed on two brood mare farms. A total of six breeding stock showed myotonic discharges and 15 were nonmyotonic. Myotonic discharges were seen in five of six horses belonging to the blood line previously implicated as being predisposed to HPP. Two of these horses had shown clinical signs of HPP. Only one of 15 breeding horses unrelated to the HPP predisposed blood line showed myotonic discharges. When both parents were non-myotonic on EMG than the F1 generation (n = 6) were also nonmyotonic. When a stallion with HPP and myotonic discharges was mated to eight nonmyotonic mares over a six year period half the animals of the F1 generation (n = 25) showed myotonic discharges. When both parents showed myotonic discharges four F1 offspring were myotonic and two were nonmyotonic on EMG testing. There was no evidence of sex linkage. The results are consistent with an autosomal dominant mode of inheritance. Hyperkalemic periodic paralysis and myotonic discharges on EMG may be different manifestations of the same underlying defect.  相似文献   
75.
76.
Multispecific resistance to benzimidazoles was studied in three selected farms. These farms had bred dairy goats for more than 15 years. The helminths were introduced with the goats at the establishment of the farms which afterwards remained isolated. Nematode resistance could then be related to their own management practices. Faecal egg count tests and egg hatch assays were performed to assess intensity of resistance. The generic (infective larvae in faecal cultures) and specific richness (adult worms) were assessed. The resistant species were Trichostrongylus colubriformis, Teladorsagia circumcincta, Haemonchus contortus and Oesophagostomum venulosum. Faecal egg count reduction tests and egg-hatch assays did not match exactly. Faecal larval counts after treatments gave a distorted picture of multispecific resistance: Haemonchus and Oesophagostomum were very largely over represented. The number of species found in the three farms was relatively low compared with other reports in goat farms of the area. This reduction of diversity might also be due in part to characteristics of breeding management and history (use of permanent pasture and introduction of goats at the establishment of farm).  相似文献   
77.
切割取样对胚胎发育的影响   总被引:2,自引:0,他引:2  
体视显微镜下,采用徒手持金属刀片和自制的玻璃切割针分别对小鼠和牛胚胎进行切割取样,并对取样后的胚胎进行体外培养48h,其发育率分别为76.7%(46/60)和80%(16/20),两者差异不显著(P>0.05);奶牛新鲜胚胎切割取样后,胚胎移植妊娠率47.1%(8/17),比对照组妊娠率59.0%(23/39)差异显著(P<0.05)。冷冻-解冻胚胎切割取样后移植妊娠率42.9%(6/17)虽然也比对照组50%低,但是差异不显著(P>0.05)。  相似文献   
78.
川北地区稻田养殖中华绒螯蟹试验初探   总被引:2,自引:0,他引:2  
本试验在四川山间湿地利用农田0.62公顷养殖中华绒螯蟹,放养苗种为1272只(135只/667m^2),个体均重7g/只左右,经160d饲养,捕获绒螯蟹875只,个体均重136.7g/只,回捕率为68.8%,饵料系数为2.45,同时水稻产量3529.7kg(375.5kg/667m^2),其总收获利润为416元/667m^2。  相似文献   
79.
羔羊全营养代乳粉对羔羊增重影响的试验   总被引:1,自引:0,他引:1  
为了研究羔羊出生后采取人工饲喂代乳粉溶液的效果,对10日龄羔羊称重,以平均日增重与母乳组比较,用t检验方法检验差异显著性。研究结果显示羔羊平均日增重试验组为0.097-0.126kg,母乳组为0.071-0.113kg,二者没有显著差异。在生产中,代乳粉能替代绵羊母乳饲喂羔羊,对多胎品系羊的推广应用以及解决绵羊缺乳、少乳或无乳问题具有重要意义。  相似文献   
80.
CHENG Feng-tao  LIU Ling 《园艺学报》2006,22(6):1222-1224
AIM:In this article,gastrointestinal tumo r-related historical ar chives of pathology in our hospital were reviewed in order to acknowledge gastro intestinal stromal tumors (GIST).METHODS:These cases were rediagnosed correctly ,these tissues were labeled with some antibodies such as CD117,CD34,α-SMA,S-100,and the ir clinical characteristics were explored.RESULTS:CD117,CD34 were expressed widely in GISTs ,the percen tage of positive expression was CD117 (50/56,89.3%),CD34 (37/56,66.1% ),respectively,α-SMA,S-100 were (17/56,30.4%),(4/56,7.1%),re spe ctively,desmin was negative in these cases.Among them,29 cases were benign a nd borderline,27 cases were malignant.The percentage of occurring in stomach a nd intestine was 91.1%.CONCLUSION:CD117,CD34 are expressed significantly in GIST,t hese might be assistant markers for GIST diagnosis.GISTs mostly occurred in sto mach and intestine.  相似文献   
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