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71.
The characteristics of the five Korean isolates of Japanese encephalitis (JE) virus were compared with those of the already reported JE virus strains from Japan and China using the hemagglutination test and polymerase chain reaction direct sequencing of the JE virus genomes (capsid/premembrane, envelope region). The hemagglutination patterns of all the isolates were distinctly different from the Nakayama-NIH strain. The optimal pH of hemagglutination of all the Korean isolates was 6.6-7.0 and the reaction range was broader than that of the Nakayama-NIH strain. The 198 nucleotide sequences in the capsid/premembrane gene region of the five Korean strains indicated that they were classified into the third genotype group, the JE strains from the countries in the temperate zone including the Nakayama-NIH, JaOArS982, and Beijing-1 strains. Four of the five Korean isolates formed a unique phylogenetic tree within the third genotype group, although the last one was genetically highly related to the Nakayama-NIH strain. The 251 nucleotide sequences in the envelope region of the five isolates were more divergent than the capsid/premembrane region. Four of the five isolates showed a large nucleotide divergency as compared with the JaOArS982 strain (< or = 12.4%), but the last one was similar to the JaOArS982 strain (98% of nucleotide homology). These results suggest the evolutionary divergence of the JE viruses isolated in Korea from the Japanese and Chinese strains and that there may exist at least two antigenically different JE virus strains in Korea.  相似文献   
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A 50 year old man presented with sudden abdominal pain, abdominal distension and shock. At emergency laparotomy a large amount of blood was found in the peritoneal cavity. There was micronodular cirrhosis of the liver and the spleen was enlarged. The bleeding was traced to distended veins in the right paracolic gutter which were oversewn and the abdomen closed. A coagulopathy was diagnosed and treatment including high dose aprotinin commenced. However, he continued to bleed and at a second laparotomy the area of previous haemorrhage was packed. Further deterioration continued until death 12 hours later. Intraperitoneal haemorrhage from ectopic varices is a rare occurrence. There is a high mortality rate usually due to an advanced coagulopathy. This is the first report of aprotinin being used in an attempt to treat this. On the basis of this report aprotinin would not seem to be of benefit for this condition.  相似文献   
75.
Two pilot studies evaluated the rate of relapse or recurrence (i.e., major depressive disorder) after cognitive therapy (CT). Two sequential cohorts included outpatients who responded to acute phase CT (A-CT) and who agreed to monthly, treatment-free follow-up. In Study 1, the Kaplan-Meier technique estimated relapse and recurrence rates of 40% at 6 months, 45% at 8 months, 50% at 12 months, 67% at 18 months, and 74% at 24 months. In Study 2, responders to A-CT received 8 months (10 sessions) of continuation phase CT (C-CT). In Study 2, relapse or recurrence was 20% at 6 and 8 months, 27% at 12 months, and 36% at 18 and 24 months after A-CT. An exploratory log-rank test showed that relapse or recurrence-free survival was greater in Study 2 than in Study 1. If replicated, this result suggests that C-CT can reduce depressive relapse or recurrence. Alternative explanations are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
BACKGROUND: About 65 percent of previously untreated adults with primary acute myeloid leukemia (AML) enter complete remission when treated with cytarabine and an anthracycline. However, such responses are rarely durable when conventional postremission therapy is administered. Uncontrolled trials have suggested that intensive postremission therapy may prolong these complete remissions. METHODS: We treated 1088 adults with newly diagnosed AML with three days of daunorubicin and seven days of cytarabine and randomly assigned patients who had a complete remission to receive four courses of cytarabine at one of three doses: 100 mg per square meter of body-surface area per day for five days by continuous infusion, 400 mg per square meter per day for five days by continuous infusion, or 3 g per square meter in a 3-hour infusion every 12 hours (twice daily) on days 1, 3, and 5. All patients then received four courses of monthly maintenance treatment. RESULTS: Of the 693 patients who had a complete remission, 596 were randomly assigned to receive postremission cytarabine. After a median follow-up of 52 months, the disease-free survival rates in the three treatment groups were significantly different (P = 0.003). Relative to the 100-mg group, the hazard ratios were 0.67 for the 3-g group (95 percent confidence interval, 0.53 to 0.86) and 0.75 for the 400-mg group (95 percent confidence interval, 0.60 to 0.94). The probability of remaining in continuous complete remission after four years for patients 60 years of age or younger was 24 percent in the 100-mg group, 29 percent in the 400-mg group, and 44 percent in the 3-g group (P = 0.002). In contrast, for patients older than 60, the probability of remaining disease-free after four years was 16 percent or less in each of the three postremission cytarabine groups. CONCLUSIONS: These data support the concept of a dose-response effect for cytarabine in patients with AML who are 60 years of age or younger. The results with the high-dose schedule in this age group are comparable to those reported in similar patients who have undergone allogeneic bone marrow transplantation during a first remission.  相似文献   
77.
We have synthesized a set of four energy transfer dyes and demonstrated their use in automated DNA sequencing. The donor dyes are the 5- or 6-carboxy isomers of 4'-aminomethylfluorescein and the acceptor dyes are a novel set of four 4,7-dichloro-substituted rhodamine dyes which have narrower emission spectra than the standard, unsubstituted rhodamines. A rigid amino acid linker, 4-aminomethylbenzoic acid, was used to separate the dyes. The brightness of each dye in an automated sequencing instrument equipped with a dual line argon ion laser (488 and 514 nm excitation) was 2-2.5 times greater than the standard dye-primers with a 2 times reduction in multicomponent noise. The overall improvement in signal-to-noise was 4- to 5-fold. The utility of the new dye set was demonstrated by sequencing of a BAC DNA with an 80 kb insert. Measurement of the extinction coefficients and the relative quantum yields of the dichlororhodamine components of the energy transfer dyes showed their values were reduced by 20-25% compared with the dichlororhodamine dyes alone.  相似文献   
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Activation and Thr286 autophosphorylation of calcium/calmodulindependent kinase II (CaMKII) following Ca2+ influx via N-methyl-D-aspartate (NMDA)-type glutamate receptors is essential for hippocampal long term potentiation (LTP), a widely investigated cellular model of learning and memory. Here, we show that NR2B, but not NR2A or NR1, subunits of NMDA receptors are responsible for autophosphorylation-dependent targeting of CaMKII. CaMKII and NMDA receptors colocalize in neuronal dendritic spines, and a CaMKII.NMDA receptor complex can be isolated from brain extracts. Autophosphorylation induces direct high-affinity binding of CaMKII to a 50 amino acid domain in the NR2B cytoplasmic tail; little or no binding is observed to NR2A and NR1 cytoplasmic tails. Specific colocalization of CaMKII with NR2B-containing NMDA receptors in transfected cells depends on receptor activation, Ca2+ influx, and Thr286 autophosphorylation. Translocation of CaMKII because of interaction with the NMDA receptor Ca2+ channel may potentiate kinase activity and provide exquisite spatial and temporal control of postsynaptic substrate phosphorylation.  相似文献   
80.
Eighteen spring-born Columbia ram, wether, and zeranol-implanted ram lambs were studied to determine the influence of castration or zeranol implants on intramuscular collagen (IMC) properties and muscle shear force values. Warner-Bratzler shear force values for longissimus muscle were greatest for ram lambs, intermediate for implanted rams, and least for wethers (P < .05). Nonreducible collagen crosslink concentration was greater in IMC of rams and implanted rams (P < .05). The IMC from rams compared with that from wethers contained proportionately more Type III than Type I collagen (P < .05); values for implanted rams were intermediate. Heat-soluble muscle collagen concentration was greater for rams and implanted rams than for wethers (P < .05); however, insoluble collagen concentration did not differ by treatment. Muscle collagen concentrations were not different for rams, wethers, or implanted rams. Increased shear force values in rams were associated with elevated collagen crosslink concentration and increased proportion of Type III collagen. Greater concentration of soluble collagen in ram IMC neither diminished nor diluted IMC crosslinking. The proportion of heat-labile collagen in the fractions did not reflect the IMC crosslinking profile for ram and wether lambs. Zeranol implantation modified IMC characteristics of rams such that shear force values and some collagen properties were similar to those of wethers.  相似文献   
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