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991.
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Objective

To identify the unusual breeding sites of two dengue vectors, i.e. Aedes albopictus (Ae. albopictus) and Aedes aegypti (Ae. aegypti).

Methods

During the second half of 2010, we performed an occasional survey in rural (Teluk Tempoyak) and urban (Gelugor) areas of Penang Island, Malaysia, to identify cryptic breeding sites.

Results

In the rural area, we found heterogeneous immature stages of Ae. albopictus in the water bowl of an encaged bird. We also observed Ae. aegypti eggs deposited in the flush tank of a toilet in the urban area.

Conclusions

It can be concluded that both breeding patterns can increase contact with hosts (humans and birds) and presumably population densities of Ae. albopictus and Ae. aegypti, thereby potentially boosting the risks for spread and transmission of arboviral diseases.  相似文献   
993.

Objective

To evaluate the acaricidal activity of extracts of three essential oils of chamomile, marjoram and Eucalyptus against Tetranychus urticae (T. urticae) Koch.

Methods

Extracts of three essential oils of chamomile, marjoram and Eucalyptus with different concentrations (0.5%, 1.0%, 2.0%, 3.0% and 4.0%) were used to control T. urticae Koch.

Results

The results showed that chamomile (Chamomilla recutita) represented the most potent efficient acaricidal agent against Tetranychus followed by marjoram (Marjorana hortensis) and Eucalyptus. The LC50 values of chamomile, marjoram and Eucalyptus for adults were 0.65, 1.84 and 2.18, respectively and for eggs 1.17, 6.26 and 7.33, respectively. Activities of enzymes including glutathione-S-transferase, esterase (α-esterase and β-esterase) and alkaline phosphatase in susceptible mites were determined and activities of enzymes involved in the resistance of acaricides were proved. Protease enzyme was significantly decreased at LC50 of both chamomile and marjoram compared with positive control. Gas chromatography-mass spectrometer (GC-MS) proved that the major compositions of Chamomilla recutita are α-bisabolol oxide A (35.251%), and trans-β-farersene (7.758%), while the main components of Marjorana hortensis are terpinene-4-ol (23.860%), p-cymene (23.404%) and sabinene (10.904%).

Conclusions

It can be concluded that extracts of three essential oils of chamomile, marjoram and Eucalyptus possess acaricidal activity against T. urticae.  相似文献   
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Survival in cytogenetically high-risk patients with acute myeloid leukemia or myelodysplastic syndromes is significantly worse in the presence of a monosomal karyotype (MK). The objective of the present study was to determine whether the same held true for primary myelofibrosis. Among 793 primary myelofibrosis patients seen at our institution, 62 displayed an unfavorable karyotype by way of complex karyotype (n = 41) or sole trisomy 8 (n = 21). Seventeen (41%) of the 41 patients with complex karyotype were classified as having an MK. Median survival was 6, 24, and 20 months in patients with MK, complex karyotype without monosomies, and sole trisomy 8, respectively (P < .0001). The corresponding 2-year leukemic transformation rates were 29.4%, 8.3%, and 0 (P < .0001); hazard ratios (95% confidence intervals) were 6.9 (1.3-37.3) and 14.8 (1.7-130.8). The prognostic relevance of MK was not accounted for by the Dynamic International Prognostic Scoring System. We conclude that MK in primary myelofibrosis is associated with extremely poor overall and leukemia-free survival.  相似文献   
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