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961.
962.
小麦白秆病是在青藏高原上为害小麦的一种新病害,在受害的叶、叶鞘及茎秆上产生草黄色条斑和椭圆形至长方形斑点两种症状。经鉴定病害由壳月孢属(Selenophoma)真菌引起。病菌在15℃黑暗条件下的马铃薯葡萄糖琼脂上培养,形成粘质状菌落,生长缓慢,不形成分生孢子器,而在菌丝上芽殖分生孢子;在15℃黑光灯照射下的燕麦琼脂等培养基上培养,形成分生孢子器。分生孢子器分生孢子新月形,无色,单胞,大小为17.9-26×2.6-3.6μ;而芽殖分生孢子的大小及形态变异较大。病菌的生长温度范围为0—20℃,以15℃为最适宜。其寄主有小麦、黑麦及冰草等。种子和幼苗经接种后,均产生系统性条斑症状。根据病菌的形态和寄主范围,小麦白秆病菌即Selenophoma donacis(pass)sprague efA.G.Johnson,由于S.donacis 只产生斑点症状,而小麦白秆病菌产生特有的系统性条斑症状,且发生温度偏低,所以认为小麦白秆病菌是在青藏高原特殊的生境条件下,形成的一个Selenophoma donacis(pass)sprague et A.G.Johnson的“白秆(albo-culmo)生态型。 相似文献
963.
964.
M. L. Killian S. L. Swenson A. L. Vincent J. G. Landgraf B. Shu S. Lindstrom X. Xu A. Klimov Y. Zhang A. S. Bowman 《Zoonoses and public health》2013,60(3):196-201
Influenza‐like illness was noted in people and pigs in attendance at an Ohio county fair in August 2007. The morbidity rate in swine approached 100% within 1–2 days of initial clinical signs being recognized, and approximately two dozen people developed influenza‐like illness. Triple‐reassortant swine H1N1 influenza viruses were identified in both pigs and people at the fair. The identified viruses (A/Sw/OH/511445/2007, A/Ohio/01/2007, and A/Ohio/02/2007) were similar to H1N1 swine influenza viruses currently found in the U.S. swine population. This case illustrates the possibility of transmission of swine influenza in settings where there is close human/swine interaction. 相似文献
965.
Insect reproduction may be affected by a number of factors including seasonal changes in larval or adult nutrition. The effect
of season on the reproductive potential ofMonochamus galloprovincialis (Olivier) females reared inPinus sylvestris L. (Scots pine) logs was investigated by constructing fertility tables for each log that differed only in the season they
were cut. Population parameters were compared among three seasonal cohorts. The intrinsic rate of increase and most of the
associated population parameters of beetles that emerged from logs cut during spring were higher than for beetles emerged
from summer and autumn logs. Slight differences were found between summer and autumn cohorts. We suggest that seasonal differences
in the nutritional quality of logs caused differences inM. galloprovincialis survival and reproductive potential.
http://www.phytoparasitica.org posting March 16, 2008. 相似文献
966.
967.
968.
Evaluation of Surgical Scrub Methods for Large Animal Surgeons 总被引:2,自引:0,他引:2
P. Y. WAN DVM Diplomate ACVS J. T. BLACKFORD DVM MS Diplomate ACVS D. A. BEMIS PhD B. W. ROHRBACH VMD MPH D. E. KNOLL VHT M. K. PROVENZA BSMT 《Veterinary surgery : VS》1997,26(5):382-385
Objective— The objective of this study was to determine the effectiveness of a 5–minute surgical scrub using either a one-brush or a two-brush technique in clean and dirty surgical procedures, and to compare the efficacy of povidone iodine with chlorhexidine as surgical scrub solutions. Study Design— Prospective clinical trial. Methods— Nine veterinarians scrubbed their hands on eight separate occasions using either povidone iodine or chlorhexidine gluconate. A 5-minute scrub and either a one-brush or two-brush technique used in both clean and dirty operations were evaluated by taking glove juice samples before scrubbing, immediately after scrubbing, and 30, 60, 90, and 120 minutes after scrubbing. Glove juice samples were cultured and the colonies were counted. Percent reductions of bacterial forming units were calculated for all eight scrub procedures. Results— All scrub procedures provided an adequate percent reduction in colony forming units (CFU) during the 2–hour sampling period. The number of CFU immediately after scrubbing were significantly lower than prescrub. At 120 minutes, there were significantly fewer CFUs than presecrub, but there were more than immediately after scrubbing. No significant difference in reduction in CFUs were detected between one-brush and two-brush techniques. Both chlorhexidine and povidone iodine scrub solutions adequately reduced bacterial colony counts for 120 minutes after scrubbing regardless of the amount of contamination before skin preparation. Conclusions— Bacterial counts after a hand scrub procedure using a one-brush technique were not significantly different than after a procedure that used a two-brush technique. Povidone iodine and chlorhexidine are equally effectively in decreasing bacterial numbers on the skin, given a variety of contamination levels present before the scrub procedure. Clinical Relevance— Surgeons may use either chlorhexidine or povidone iodine for antiseptic preparation of their hands before surgery. A two-brush technique is not necessary. 相似文献
969.
The Canadian Cooperative Wildlife Health Centre and surveillance of wild animal diseases in Canada. 下载免费PDF全文
F A Leighton G A Wobeser I K Barker P Y Daoust D Martineau 《The Canadian veterinary journal. La revue veterinaire canadienne》1997,38(5):279-284
The Canadian Cooperative Wildlife Health Centre (CCWHC) was established in 1992 as an organization among Canada's 4 veterinary colleges, with a mandate to apply veterinary medicine to wildlife management and conservation in Canada. A major function of the CCWHC is nation-wide surveillance of wild animal diseases. Disease surveillance is conceived as consisting of 4 different activities: detection, diagnosis, information management, and use of information. In the CCWHC surveillance program, detection of disease is carried out by a wide range of professional and avocational field personnel, and much effort is expended to stimulate and support this activity. Diagnosis is done by personnel of provincial and federal veterinary laboratories and the CCWHC. Information management is achieved through a national database of wildlife disease incidents developed and maintained by the CCWHC. Use of information is enabled through established channels for distribution of information derived from the surveillance program to persons responsible for wildlife programs and policies, and to the public. There has been a high demand for the services of the CCWHC since its establishment. The CCWHC responds to approximately 2000 requests for information annually, distributes its newsletter to over 1700 recipients, examines approximately 1200 wild animal submissions each year, and has accumulated records of over 5000 disease incidents in its database. Technical information from the CCWHC has benefited federal, provincial/territorial, and nongovernment wildlife agencies; endangered species recovery programs; federal and provincial veterinary services; and federal and provincial public health programs. 相似文献
970.
Plaque assay of bovine coronavirus in BEK-1 cells 总被引:1,自引:0,他引:1