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81.
LESLIE G. UNDERHILL PETER A. BARTLETT LUKAS BAUMANN ROBERT J.M. CRAWFORD BRUCE M. DYER RE GILDENHUYS DEON C. NEL TERENCE B. OATLEY MEREDITH THORNTON LEISHA UPFOLD ANTHONY J. WILLIAMS PHILIP A. WHITTINGTON ANTON C. WOLFAARDT 《Ibis》1999,141(1):29-37
The bulk ore carrier Apollo Sea sank near Dassen Island, South Africa, on 20 June 1994 during a period of winter storms. Approximately 10 000 African (Jackass) Penguins Spheniscus demersus were oiled, collected and transported to the SANCCOB rescue centre; 5213 were released after cleaning, 4076 with flipper bands. We believe that most of the penguins oiled during this incident reached an island or the mainland alive, and that there was no mass mortality in the wild at the time of the oil spill. Birds from all parts of the breeding range were oiled, but most were from Robben and Dassen Islands. The overwhelming majority of released birds made the transition from the rescue centre to the wild successfully; 2652 had been resighted at breeding colonies within two years of their release; the cumulative number of birds was increasing steadily and an asymptote had not been reached by August 1996. There was a wide dispersal of released penguins, with recoveries and resightings over 1800 km of coastline between Algoa Bay and Walvis Bay. 相似文献
82.
83.
CengizTURE ElifSALKURT 《植物学报(英文版)》2005,47(6):660-667
Airborne pollen grains in the atmosphere of Bozuyuk were investigated over a 2 yr period from 2000 to 2001 using a Durham sampler. A total number of pollen grains of 5 170 pollen grains belonging to 32 taxa were identified and recorded along with some unidentified pollen grains. Of all the pollen grains, 78.66% were arboreal, 19.20% were non-arboreal, and 2.12% were unidentified. The majority of pollen grains investigated were Pinus, Platanus, Quercus, Cupressaceae, Poaceae, Fagus, Salix, Rosaceae, Urticaceae, Asteraceae, and Chenopodiaceae. The maximum number of pollen grains was recorded in May. 相似文献
84.
目的:探讨拉米夫定辅助治疗对肺结核合并乙型肝炎患者的肝功能的影响和安全性。方法:选择2009年1月至2013年6月在我科门诊就诊或住院的肺结核合并乙型肝炎患者84例,随机均分为对照组与观察组,对照组给予常规治疗措施,观察组在上述基础上加用拉米夫定治疗,检测和比较两组患者治疗前和治疗后6个月相关临床指标及不良反应的发生情况。结果:治疗前,两组患者的总胆红素(TBIL)、丙氨酸转氨酶(ALT)、谷草转氨酶(AST)和HBV-DNA定量结果比较,差异均无统计学意义(均P0.05);治疗6个月后,观察组以上指标均显著低于对照组,差异均具有统计学意义(均P0.05)。两组患者治疗过程中均出现恶心、腹胀、乏力、肝区不适与肝功能损害,观察组以上不良反应的发生率均显著低于对照组,差异具有统计学意义(均P0.05)。结论:在肺结核合并乙型肝炎患者的抗结核药物治疗过程中加用拉米夫定不仅可显著抑制患者肝功能的损害,且安全性性更高。 相似文献
85.
Conserved sequence motifs, alignment, and secondary structure for the third domain of animal 12S rRNA 总被引:14,自引:3,他引:14
Hickson RE; Simon C; Cooper A; Spicer GS; Sullivan J; Penny D 《Molecular biology and evolution》1996,13(1):150-169
Secondary structure models are an important step for aligning sequences,
understanding probabilities of nucleotide substitutions, and evaluating the
reliability of phylogenetic reconstructions. A set of conserved sequence
motifs is derived from comparative sequence analysis of 184 invertebrate
and vertebrate taxa (including many taxa from the same genera, families,
and orders) with reference to a secondary structure model for domain III of
animal mitochondrial small subunit (12S) ribosomal RNA. A template is
presented to assist with secondary structure drawing. Our model is similar
to previous models but is more specific to mitochondrial DNA, fitting both
invertebrate and vertebrate groups, including taxa with markedly different
nucleotide compositions. The second half of the domain III sequence can be
difficult to align precisely, even when secondary structure information is
considered. This is especially true for comparisons of anciently diverged
taxa, but well-conserved motifs assist in determining biologically
meaningful alignments. Patterns of conservation and variability in both
paired and unpaired regions make differential phylogenetic weighting in
terms of "stems" and "loops" unsatisfactory. We emphasize looking carefully
at the sequence data before and during analyses, and advocate the use of
conserved motifs and other secondary structure information for assessing
sequencing fidelity.
相似文献
86.
Christopher RE McEvoy Paul D van Helden Robin M Warren Nicolaas C Gey van Pittius 《BMC evolutionary biology》2009,9(1):237-21
Background
PPE38 (Rv 2352c) is a member of the large PPE gene family of Mycobacterium tuberculosis and related mycobacteria. The function of PPE proteins is unknown but evidence suggests that many are cell-surface associated and recognised by the host immune system. Previous studies targeting other PPE gene members suggest that some display high levels of polymorphism and it is thought that this might represent a means of providing antigenic variation. We have analysed the genetic variability of the PPE38 genomic region on a cohort of M. tuberculosis clinical isolates representing all of the major phylogenetic lineages, along with the ancestral M. tuberculosis complex (MTBC) member M. canettii, and supplemented this with analysis of publicly available whole genome sequences representing additional M. tuberculosis clinical isolates, other MTBC members and non tuberculous mycobacteria (NTM). Where possible we have extended this analysis to include the adjacent plcABC and PPE39/40 genomic regions. 相似文献87.
MATTHEW D. HALL LUC F. BUSSIÈRE MARCO DEMONT PAUL I. WARD ROBERT C. BROOKS 《Molecular ecology》2010,19(3):610-619
The outcome of mate choice depends on complex interactions between males and females both before and after copulation. Although the competition between males for access to mates and premating choice by females are relatively well understood, the nature of interactions between cryptic female choice and male sperm competition within the female reproductive tract is less clear. Understanding the complexity of postcopulatory sexual selection requires an understanding of how anatomy, physiology and behaviour mediate sperm transfer and storage within multiply mated females. Here we use a newly developed molecular technique to directly quantify mixed sperm stores in multiple mating females of the black field cricket, Teleogryllus commodus. In this species, female postcopulatory choice is easily observed and manipulated as females delay the removal of the spermatophore in favour of preferred males. Using twice‐mated females, we find that the proportion of sperm in the spermatheca attributed to the second male to mate with a female (S2) increases linearly with the time of spermatophore attachment. Moreover, we show that the insemination success of a male increases with its attractiveness and decreases with the size of the female. The effect of male attractiveness in this context suggests a previously unknown episode of mate choice in this species that reinforces the sexual selection imposed by premating choice and conflicts with the outcome of postmating male harassment. Our results provide some of the clearest evidence yet for how sperm transfer and displacement in multiply mated females can lead directly to cryptic female choice, and that three distinct periods of sexual selection operate in black field crickets. 相似文献
88.
Quezada-Rivera JJ RE Soria-Guerra FS Pérez-Juárez L Martínez-González SE Valdés- Rodríguez NL Vasco-Méndez JF Morales-Domínguez 《Phyton》2019,88(1):25-35
The use of antimicrobial peptides (AMPs) synthesized
by bacteria (bacteriocins) is an alternative for combating multidrug
resistant bacterial strains and their production by recombinant route
is a viable option for their mass production. The bacteriocin E-760
isolated from the genus Enterococcus sp. has been shown to possess
inhibitory activity against Gram-negative and Gram-positive
bacteria. In this study, the expression of a chimeric protein coding
for E-760 in the nucleus of C. reinhardtii was evaluated, as well as,
its antibacterial activity. The synthetic gene E-760S was inserted
into the genome of C. reinhardtii using Agrobacterium tumefaciens.
A transgenic line was identified in TAP medium with hygromycin
and also by PCR. The increment in the culture medium temperature
of the transgenic strain at 35 °C for 10 minutes, increased the
production level of the recombinant protein from 0.14 (Noninduced
culture, NIC) to 0.36% (Induced culture, IC) of total soluble
proteins (TSP); this was quantified by an ELISA assay. Recombinant
E-760 possesses activity against Staphylococcus aureus in 0.34 U
log, Streptococcus agalactiae in 0.48 U log, Enterococcus faecium in
0.36 U log, Pseudomonas aeruginosa in 2 U log and for Klebsiella
pneumoniae, the activity was 0.07 U log. These results demonstrate
that the nucleus transformation of C. reinhardtii can function as
a stable expression platform for the production of the synthetic
gene E-760 and it can potentially be used as an antibacterial agent. 相似文献
89.
90.