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61.
A DNA vaccine encoding the envelope glycoprotein from a fish rhabdovirus, viral hemorrhagic septicemia virus (VHSV), has previously been shown to induce both early and long time protection against the virus in rainbow trout. Challenge experiments have revealed that the immunity established shortly after vaccination is cross-protective against heterologous fish rhabdoviruses. In this study, we show that the DNA vaccine encoding the VHSV glycoprotein also induces early protection against a non-enveloped, positive-sense RNA virus belonging to the Nodavirus family, the Atlantic halibut nodavirus (AHNV). In a vaccine efficacy test using juvenile turbot as model fish, the fish injected with the VHSV vaccine were completely protected against a nodavirus challenge performed 8 days post vaccination, while the cumulative mortality in the control group reached 54%. A DNA vaccine carrying the gene encoding the capsid protein of AHNV revealed no protective properties against the nodavirus challenge. Histological examination of muscle tissue sections from the vaccine injection site showed that the DNA vaccine against VHSV triggered a pronounced inflammatory response in turbot similar to what has earlier been observed in rainbow trout.  相似文献   
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Three analogs of 6-aminodopamine were synthesized and tested for their ability to deplete the central nervous system of norepinephrine and dopamine. The compounds were analogs in which the aliphatic nitrogen of the ethyl side chain was substituted with dimethyl, isopropyl, and methyl groups. The first two compounds showed only very weak depletion of norepinephrine stores, while having no effect on dopamine levels. The third compound was not tested due to its instability.  相似文献   
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OBJECTIVE: To determine if interval tubal sterilization leads to a change in female sexual interest or pleasure and to identify predictors of a positive or negative effect. METHODS: Our study population comprised 4576 women enrolled in a prospective, multicenter cohort study between 1978 and 1983. Potential demographic, clinical, and surgical predictors of sexual outcome were tested for significant variation from the overall pattern of unchanged, increased, and decreased sexual interest and pleasure. RESULTS: Over 80% of the 4576 study women reported no consistent change in either sexual interest (80.0%) or pleasure (81.7%) after interval tubal sterilization. Among women with consistent change, positive effects were reported ten and 15 times more often than negative effects for sexual interest and pleasure, respectively. All subgroups of women, except for those with poststerilization regret, were significantly (P <.05) more likely to experience increased rather than decreased interest or pleasure. Women with poststerilization regret were the subgroup most likely to have a negative effect; in multivariate analyses, poststerilization regret was the only factor to be a predictor for decreased interest (odds ratio 4.0) and decreased pleasure (odds ratio 5.1). Similarly, women reporting regret were significantly less likely to report increased interest or pleasure. Whether the regret or the decreased sexual interest or pleasure occurred first is unclear. CONCLUSION: Interval tubal ligation is unlikely to result in changed sexual interest or pleasure. Among those with change, the majority experienced positive sexual effects.  相似文献   
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OBJECTIVE: To determine patterns of resistance for isolates of Streptococcus pneumoniae recovered from middle ear fluids of children from eight children's hospitals between September, 1994, and August, 1997. METHODS: Data were extracted retrospectively from the medical records of eight children's hospitals. A standardized data form was completed for each episode of pneumococcal infection. Systemic isolates (blood and pleural, synovial and spinal fluids) of S. pneumoniae were collected during the same period. All isolates of S. pneumoniae from each center were sent to a central laboratory. Susceptibility to penicillin and ceftriaxone was determined by microbroth dilution. Organisms were considered nonsusceptible to penicillin if the minimum inhibitory concentration was > or = 0.1 microg/ml and nonsusceptible to ceftriaxone if the minimum inhibitory concentration was > or = 1.0 microg/ml. RESULTS: S. pneumoniae was recovered from the middle ear fluids of 707 children from all centers during the study period. Thirty-nine (5.5%) were infections recorded at 4 centers which evaluated middle ear fluid only sporadically and were not included in this analysis. The remaining 668 infections reported by the 4 remaining participating hospitals reflect the experience of 608 children. There were 54% boys; 440 (73%) were Caucasian, 111 (18%) were African-American, 38 (6%) were Hispanic and for 19 (3%) the race was not recorded. The children ranged in age from 16 days to 13.8 years with a mean (+/-sD) of 26.0 (+/- 26.1) months. Children who received antibiotics in the 30 days before the middle ear isolate was recovered were more likely to harbor a resistant strain of S. pneumoniae than children who had not recently received an antibiotic (P < 0.001). Isolates recovered from children with spontaneous otorrhea were more likely to be susceptible to penicillin than isolates recovered during myringotomy, with or without the insertion of tympanostomy tubes (P < 0.01). There was wide variation in the susceptibility of middle ear isolates to penicillin and ceftriaxone according to geographic location; however, in every locale the middle ear isolates were less likely to be susceptible to penicillin and ceftriaxone than systemic isolates of S. pneumoniae. CONCLUSION: The prevalence of penicillin-resistant and cephalosporin-resistant S. pneumoniae in middle ear isolates derived from children cared for at four different children's hospitals was quite variable. In some locations the prevalence of resistance is still increasing, whereas in other areas the rate of resistance was at a plateau during the period of surveillance. The prevalence of isolates of S. pneumoniae susceptible to penicillin and ceftriaxone was always less common among middle ear isolates than among systemic isolates. Previous antibiotic use remains the most predictive factor for the recovery of isolates resistant to penicillin and ceftriaxone.  相似文献   
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Leishmaniasis is one of the world's most neglected infectious diseases, affecting around 12 million people and more than 350 million at risk of infection. The clinical picture varies from self-healing cutaneous lesions to severe visceral infections, but still no commercial vaccines for humans are available and the currently used drugs have unpleasant side effects. Here we report a real-time PCR assay targeting the arginine permease gene AAP3 that can be applied for all the nine different species of the Leishmania genus tested; 4 Old World species and 5 New World species, from both L. (Leishmania) and L. (Viannia) subgenera. No cross-reaction was seen with Trypanosoma cruzi, Trypanosoma brucei, human or mouse genomic DNA. The assay has a high sensitivity, with a limit of detection of 10 fg DNA for L. (L.) major and L. (L.) donovani, and 100 fg DNA for L. (V.) braziliensis, and can be used for both qualitative and quantitative purposes. This AAP3-Assay, run in duplex with a host specific gene-assay, was also successfully used for quantification of parasite load of footpads from L. (L.) major-infected mice. It can therefore be a valuable tool in applications like monitoring effects of drugs, the selection of vaccine candidates and in screening patients, including asymptomatic carriers.  相似文献   
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