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1.
Vaccination with DNA and recombinant vaccinia viruses (rec.VV) has been studied with the coxsackievirus B3 (CVB3) model system. Plasmids encoding all structural proteins of CVB3, when injected intramuscularly, induced only low levels of virus-specific antibodies. However, DNA vaccination with the major structural protein VP1 protected 72.2% of mice from lethal challenge, whereas VP1 expressed by rec.VV was much less efficient.  相似文献   
2.
Clinical evidence suggests that there may be some relationship between the occurrence of peptic ulcers and the season of the year. As little experimental work has been carried out on this subject, three drugs commonly used to induce experimental ulcers in rats (acetylsalicylic acid, 300 mg/kg; phenylbutazone, 200 mg/kg; reserpine, 10 mg/kg) were tested every month for one year under standardised experimental conditions (Ta, RH, LD 12:12). In rats given phenylbutazone the maximum area of ulceration was found in October and December, and in rats given acetylsalicylic acid in February and March. In rats given reserpine, there were no significant monthly variations. An influence of climatic factors on ulcer induction cannot be completely excluded. Endogenous conditions might also account for the monthly differences in ulceration.  相似文献   
3.
A comparative bioacustic analysis of vocalizations of the prosimian subfamily Galaginae revealed that morphologically similar sibling taxa within the main groups of the lesser galagos and the greater galagos can be reliably identified phenotypically on the basis of the acoustic structure of their loud call or advertisement call. Results confirm the separation of two distinct species of greater galagos, Galago crassicaudatus and Galago garnettii, and strongly suggest the discrimination of three distinct species from the senegalensis lesser bushbaby group, Galago senegalensis, Galago moholi and Galao zanzibaricus. An investigation of the ontogenetic development of the loud call indicated that it is derived from the infant's isolation call, displaying in all studied bushbaby taxa a fairly similar acoustic pattern. Shared acoustic characters of the loud call among the different taxa as well as the infant's isolation call were used to propose a hypothesis about the phylogenetic affinities in bushbabies. The results seem to be supported by recent fossil records.  相似文献   
4.
The nuclear mutation pet ts1402 prevents proteolytic processing of the precursor of cytochrome oxidase subunit 2 (cox2) in Saccharomyces cerevisiae. The structural gene PET1402 was isolated by genetic complementation of the temperature-sensitive mutation. DNA sequence analysis identified a 1206-bp open reading frame, which is located 215 by upstream of the PET122 gene. The DNA sequence of PET1402 predicts a hydrophobic, integral membrane protein with four transmembrane segments and a typical mitochondrial targeting sequence. Weak sequence similarity was found to two bacterial proteins of unknown function. Haploid cells containing a null allelle of PET1402 are respiratory deficient.  相似文献   
5.
Abstract The sequence of the cohesive ends of actinophage RP3 DNA has been determined. As with all other phages of Gram-positive bacteria that have been studied sofar, RP3 DNA has 3'-protruding ends. A shuttle cosmid has been constructed containing this cos area which can be efficiently transduced by phage RP3 to host cells of Streptomyces rimosus .  相似文献   
6.
Summary We report a newborn with incontinentia pigmenti Bloch-Sulzberger and male phenotype. Chromosome analysis revealed a Klinefelter's syndrome 47,XXY. These findings are compatible with the hypothesis of dominant sexlinked genes carried on the X-chromosome in this disease.
Zusammenfassung Wir berichten über ein neugeborenes Kind mit männlichem Phänotyp bei Incontinentia pigmenti Bloch-Sulzberger. Bei der klinischen Abklärung fand sich die Gonosomenaberration eines Klinefelter-Syndroms 47,XXY. Dieser Befund geht konform mit der Vermutung eines dominant X-gekoppelten Erbganges dieser seltenen Hauterkrankung.
  相似文献   
7.
Ohne Zusammenfassung
Long-term telemetry of body temperature with synchronous measurement of metabolic rate in torpid and non-torpid Blue-naped Mousebirds (Urocolius macrourus)
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8.
Summary Thirty-four wines that showed problems during malolactic fermentation were obtained from five different German wineries and were examined for the presence of phages using electron microscopy and the agar spot-test. Phages were discovered in 11 of the wines and host strains were found for ten of these phages. The phages were characterized on the basis of their morphology, host range and protein profiles. Furthermore the ten phages could be divided into four groups by restriction enzyme analysis of the phage DNA. This grouping was consistent with results based on morphology, protein composition and host range analysis. Correspondence to: E. K. Arendt  相似文献   
9.
Infant-carrying in a family group of siamangs with twin offspring was observed during a 2-week period. The twins were about 11 months old at the time of the study. One or both twins were usually carried by their father, but hardly ever by their mother. A considerable amount of infant-carrying was also contributed by the twins' juvenile brother. Helping behavior (defined as the care of offspring by individuals who are not their parents) is not normally known to occur in siamangs or other hylobatids. We suggest that the presence of multiple offspring may have facilitated the occurrence of infant-carrying exhibited by a nonparental family member. This finding may point to one of the mechanisms influencing the occurrence of helping behavior in general.  相似文献   
10.
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