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991.
992.
Caitlin M. Cossaboom Laura Córdoba Dianjun Cao Yan-Yan Ni Xiang-Jin Meng 《Journal of virology》2012,86(23):13124-13125
Hepatitis E virus (HEV) is a single-strand positive-sense RNA virus in the family Hepeviridae. The disease caused by HEV, hepatitis E, is an important public health problem in developing countries of Asia and Africa and is also endemic in many industrialized countries, including the United States. HEV has been identified from several other animal species in addition to humans, including the pig, chicken, mongoose, deer, rabbit, ferret, bat, and fish. Here we report the complete genome sequence of the first strain of HEV from rabbits in the United States. Sequence and phylogenetic analyses revealed that the U.S. rabbit HEV is a distant member of the zoonotic genotype 3 HEV, thus raising a concern for potential zoonotic human infection. A unique 90-nucleotide insertion within the X domain of the ORF1 was identified in the rabbit HEV, and this insertion may play a role in the species tropism of HEV. 相似文献
993.
In the development of the horseshoe crab, Limulus polyphemus, the fertilized egg undergoes a complicated cleavage (Stages 1–3) resulting in blastoderm formation (Stage 4). Stage 1 involves intralecithal cleavage and consists of nine discrete surface modifications (events) which have been briefly described with light microscopy by Brown and Barnum ('83). Since in Stage 1 the cortical reaction (events 1–4) has already been examined with ultrastructural methods, the objectives of the present study were to examine with scanning electron microscopy: (1) the first two of three intermittent granulations (events 5 and 7), and (2) the associated events characterized by smooth surfaces (events 4, 6, and 8). The first granulation occurs 2 1/2 to 3 hours after fertilization (22°C) and lasts approximately 1 1/2 hours. The second granulation appears approximately 5 hours after fertilization and lasts about 3 hours. The dynamic changes that occur during the two granulations involve the transformation of a smooth appearing embryonic surface, liberally coated with microvilli, into a granule-dominated surface on which microvilli are greatly reduced in number. Also of considerable interest are the numerous projections which begin to appear on the surface near the end of the second granulation (event 7) and dominate the surface of the following smooth step stage (event 8). Hypotheses on the significance of these dynamic changes and surface modifications involve relationships to the cell cycle, possible mechanisms for membrane storage, and secretory function. 相似文献
994.
Fusarium oxysporum f. sp. lycopersici and Rhizoctonal solani were grown in a complete 1.0 mM nutrient solution, and in solutions where Ca, Fe, K, Mg, N, P, and S were either excluded (0.0 mM) or included at depleted levels (0.1 mM) while all other constituents were maintained at 1.0 mM levels. Dry weight of both fungi were determined. For both fungi some of the lowest dry weights were recorded for samples grown in the complete solution. Exclusion of K, Mg, and S significantly increased dry weight of Fusarium. Inclusion at the 0.1 mM level of most components significantly increased Fusarium dry weight over values for both the complete and corresponding excluded nutrient solutions. The exception was S where there was no difference between excluded and 0.1 mM solutions. For Rhizoctonia dry weights in Fe excluded solutions were less than the complete solution, while dry weights in S excluded solutions were greater than the complete solution. At the 1.0 mM level Fe, K, and Mg dry weights were significantly increased over the dry weights produced in both the complete and deficient solutions. 相似文献
995.
996.
M C Peterson 《The Western journal of medicine》1994,161(2):148
Campylobacter jejuni is an almost ubiquitous, microaerophilic, gram-negative rod. Outbreaks have been associated with drinking raw milk or contaminated water and eating poultry. Campylobacter jejuni accounts for 3.2% to 6.1% of cases of diarrheal illness in the general population of the United States, and infected patients frequently present with abdominal pain and fever. Less frequently, C jejuni is responsible for bacteremia, septic arthritis, septic abortion, and other extraintestinal infections. Reactive arthritis, Reiter''s syndrome, the Guillain-Barré syndrome, and pancreatitis may accompany or follow C jejuni enterocolitis. Campylobacter jejuni is an important cause of diarrheal illness and is a more commonly identified stool organism than Salmonella or Shigella species. Recurrent and chronic infection is generally reported in immunocompromised hosts. 相似文献
997.
998.
M.S. Blake K.H. Johnston G.J. Russell-Jones E.C. Gotschlich 《Analytical biochemistry》1984,136(1):175-179
A rapid, sensitive method has been developed to detect antibody-antigen complexes on “Western blots.” The methods of H. Towbin, T. Staehlin, and J. Gordon were used to separate and blot the antigens onto nitrocellulose. The remaining sites of attachment were blocked and the nitrocellulose was washed with polyoxyethylenesorbitan monolaurate (Tween 20). The blot was then reacted with the antiserum or hybridoma supernate to be tested. After the antigen-antibody reaction was completed, the blot was washed and treated with anti-antibody which has been conjugated to alkaline phosphatase. The alkaline phosphatase was detected by the reduction of the tetrazolium salt to diformazan by the hydrogen ions released in the formation of indigo by the reaction of the phosphatase on the indoxyl phosphate. The advantages of this method over previously described techniques are (1) use of Tween 20 allows the blot to be stained with Coomassie blue, (2) the substrates of the alkaline phosphatase reaction are stable for long periods of time, (3) the reaction products form an intense blue color which does not fade, (4) the resolution is extremely good with little to no band broadening, (5) the reaction is sensitive to picogram quantities of antigen, and (6) the reaction is quantitative. 相似文献
999.
1000.