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61.
Strong raptor population declines have recently been reported in sub-Saharan West Africa, where the pressure on wildlife and their supporting habitats is particularly high. This makes it imperative to understand the role of land-use on landscape-scale patterns of raptors and to define priority areas for conservation. We examine landscape-scale community patterns of raptors in biogeographical zones with different degrees of anthropogenic land-use and assess the role of protected areas in maintaining such patterns. We recorded raptors along road transects in Cameroon’s savannas, covering four years and 7,340–7,700 km in wet and dry seasons, in three biogeographical zones: the relatively well-preserved Inundation and Guinea zones to the north and south of the heavily exploited Sudan zone. The Inundation zone had the largest species pool and Palearctic raptor richness and abundance. The Guinea zone had the largest Afrotropical raptor species pool, while raptor diversity and richness were higher there than in the Sudan zone. The abundance of only one species (Fox Kestrel) peaked in the Sudan zone and only one large-bodied raptor (Hooded Vulture) with a Sudan-centered distribution was more common there than in the other zones. Our results suggest that land-use as determined by protected areas and human exploitation may override the role of biogeographical zonation in shaping raptor assemblages. Comparable patterns of raptor richness and diversity inside and outside protected areas suggest that both protected areas and partly cultivated peripheral zones act as important foraging and source areas, ensuring the preservation of diverse raptor assemblages at the landscape scale. Finally, our data illustrate the comparatively high richness of Cameroon’s and West Africa’s savanna raptor communities on a continental and global scale, underlining their importance for raptor conservation. 相似文献
62.
63.
Michiel B. Haeseker Sander Croes Cees Neef Cathrien A. Bruggeman Leo M. L. Stolk Annelies Verbon 《PloS one》2014,9(11)
Background
To compare vancomycin pharmacokinetic parameters in patients with and without neutropenia.Methods
Patients ≥18 years admitted on general wards were included. Routinely vancomycin trough and peak plasma concentrations were measured with a fluorescence polarization immunoassay. Pharmacokinetic parameters of individual patients were determined with maximum a posterior Bayesian estimation (MW Pharm 3.60). Neutropenia was defined as neutrophils <0.5×109 cells/L.Principal Findings
A total of 171 patients were included. Patients with neutropenia (n = 56) had higher clearance of vancomycin (CLva), 67 (±26) mL/min, compared to patients without neutropenia (n = 115), CLva 50 (±22) mL/min (p<0.001). No significant difference was found in serum creatinine and vancomycin volume of distribution. Neutropenia was positively associated with CLva, independently of relevant co-variables (B: 12.122, 95%CI: 1.095 to 23.149, p = 0.031). On average patients with neutropenia needed 33% higher doses of vancomycin to attain adequate exposure, i.e. AUC24≥400 mg×h/L. Furthermore, 15 initially neutropenic patients in our study group received vancomycin for a second administration period. Ten patients received the second administration period during another neutropenic period and 5 patients during a non-neutropenic phase. All 5 patients with vancomycin during both neutropenic and non-neutropenic phase had higher CLva (91 (±26) mL/min) during the neutropenic period and lower CLva (45 (±10) mL/min) during the non-neutropenic phase (p = 0.009).Conclusion
This study shows that most patients with neutropenia have augmented CLva. In a small group of patients that received vancomycin during two episodes, the augmented CLva seems to be reversible in the non-neutropenic period. Our data indicate that it is important to increase the daily dose with one third in patients with neutropenia (from 15 mg/kg twice daily to 13 mg/kg three times daily). Frequent performance of therapeutic drug monitoring in patients with neutropenia may prevent both therapy failure due to low AUCs and overcomes toxicity due to high vancomycin trough concentrations during recovery from neutropenia. 相似文献64.
Natália H Mendes Fernando AF Melo Adolfo CB Santos José RC Pandolfi Elisabete A Almeida Rosilene F Cardoso Henri Berghs Suzana David Faber K Johansen Lívia G Espanha Sergio RA Leite Clarice QF Leite 《BMC research notes》2011,4(1):269
Background
Tuberculosis is a major health problem in São Paulo, Brazil, which is the most populous and one of the most cosmopolitan cities in South America. To characterize the genetic diversity of Mycobacterium tuberculosis in the population of this city, the genotyping techniques of spoligotyping and MIRU were applied to 93 isolates collected in two consecutive years from 93 different tuberculosis patients residing in São Paulo city and attending the Clemente Ferreira Institute (the reference clinic for the treatment of tuberculosis).Findings
Spoligotyping generated 53 different spoligotype patterns. Fifty-one isolates (54.8%) were grouped into 13 spoligotyping clusters. Seventy- two strains (77.4%) showed spoligotypes described in the international databases (SpolDB4, SITVIT), and 21 (22.6%) showed unidentified patterns. The most frequent spoligotype families were Latin American Mediterranean (LAM) (26 isolates), followed by the T family (24 isolates) and Haarlem (H) (11 isolates), which together accounted for 65.4% of all the isolates. These three families represent the major genotypes found in Africa, Central America, South America and Europe. Six Spoligo-International-types (designated SITs by the database) comprised 51.8% (37/72) of all the identified spoligotypes (SIT53, SIT50, SIT42, SIT60, SIT17 and SIT1). Other SITs found in this study indicated the great genetic diversity of M. tuberculosis, reflecting the remarkable ethnic diversity of São Paulo city inhabitants. The MIRU technique was more discriminatory and did not identify any genetic clusters with 100% similarity among the 93 isolates. The allelic analysis showed that MIRU loci 26, 40, 23 and 10 were the most discriminatory. When MIRU and spoligotyping techniques were combined, all isolates grouped in the 13 spoligotyping clusters were separated.Conclusions
Our data indicated the genomic stability of over 50% of spoligotypes identified in São Paulo and the great genetic diversity of M. tuberculosis isolates in the remaining SITs, reflecting the large ethnic mix of the São Paulo city inhabitants. The results also indicated that in this city, M. tuberculosis isolates acquired drug resistance independently of genotype and that resistance was more dependent on the selective pressure of treatment failure and the environmental circumstances of patients.65.
Background
Annually, 41,000 people in the Netherlands have strokes. This has multiple physical and psychosocial consequences. Most patients return home after discharge from hospital. Quality aftercare by general practitioners is important to support patients at home. The purpose of this study is to examine the wellbeing of patients who returned home immediately after discharge from hospital, one year post stroke, in comparison with the general Dutch population of the same age and to determine factors that could influence wellbeing. 相似文献66.
Changes in the adenylate energy charge and the induction of sporulation in Saccharomyces diastaticus
The induction of sporulation in yeast is generally accompanied by a sharp increase in energy metabolism which is evidenced
by a rise of the adenylate energy charge by that time. The energy charge can be held at a low level by limitation of the phosphate
supply in the growth medium. Ascus formation remains unaffected by this treatment. This suggests that the rise in ATP production
normally encountered during early sporulation is not essential for the initiation of sporulation. 相似文献
67.
68.
Phase change in lily bulblets regenerated in vitro 总被引:1,自引:0,他引:1
During the development of the lily ( Lilium ), three phases can be distinguished: the juvenile, the vegetative adult and the flowering phase. Juvenile bulblets sprout with one or a few leaves whereas vegetative adult bulblets sprout with a stem with elongated internodes. The transition to the vegetative adult phase was studied in lily ( Lilium × cv. Star Gazer) bulblets regenerating on bulb scale segments in vitro. The phase change was marked by the development of a tunica-corpus structure in the apical meristem which leads to the formation of an actively growing stem primordium. This structure is absent in juvenile bulblets. Juvenile bulblets first developed competence for phase change during a culture period of at least 6 weeks at 25°C. Subsequent induction of the phase change occurred during a period of 2 weeks at lower temperature (15°C). A major factor influencing phase transition was bulblet weight. Small bulblets never formed a stem whereas large bulblets always formed a stem under inducing conditions. Large bulblets more often formed a stem than small ones but the relation between bulb growth and phase transition was not absolute. A high sucrose concentration, a large explant and a prolonged period for competence development stimulated bulb growth but also phase transition independently of growth. Lowering the concentration of MS-minerals reduced bulb growth but did not affect phase transition. Under these conditions, phase change was correlated with a low phosphorus content. 相似文献
69.
Background
Drosophila mojavensishas been a model system for genetic studies of ecological adaptation and speciation. However, despite its use for over half a century, no linkage map has been produced for this species or its close relatives.Results
We have developed and mapped 90 microsatellites in D. mojavensis, and we present a detailed recombinational linkage map of 34 of these microsatellites. A slight excess of repetitive sequence was observed on the X-chromosome relative to the autosomes, and the linkage groups have a greater recombinational length than the homologous D. melanogaster chromosome arms. We also confirmed the conservation of Muller's elements in 23 sequences between D. melanogaster and D. mojavensis.Conclusions
The microsatellite primer sequences and localizations are presented here and made available to the public. This map will facilitate future quantitative trait locus mapping studies of phenotypes involved in adaptation or reproductive isolation using this species. 相似文献70.
Wong CW Heng CL Wan Yee L Soh SW Kartasasmita CB Simoes EA Hibberd ML Sung WK Miller LD 《Genome biology》2007,8(5):R93
DNA microarrays used as 'genomic sensors' have great potential in clinical diagnostics. Biases inherent in random PCR-amplification, cross-hybridization effects, and inadequate microarray analysis, however, limit detection sensitivity and specificity. Here, we have studied the relationships between viral amplification efficiency, hybridization signal, and target-probe annealing specificity using a customized microarray platform. Novel features of this platform include the development of a robust algorithm that accurately predicts PCR bias during DNA amplification and can be used to improve PCR primer design, as well as a powerful statistical concept for inferring pathogen identity from probe recognition signatures. Compared to real-time PCR, the microarray platform identified pathogens with 94% accuracy (76% sensitivity and 100% specificity) in a panel of 36 patient specimens. Our findings show that microarrays can be used for the robust and accurate diagnosis of pathogens, and further substantiate the use of microarray technology in clinical diagnostics. 相似文献