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91.
Specimens of the parasitic siphonostomatoid copepod Caligus tenuifurcatus Wilson, 1937 were collected from the oral cavity of the yellowfin snook, Centropomus robalito Jordan et Gilbert; the white snook, C. viridis Lockington (Perciformes, Centropomidae), and the yellow snapper, Lutjanus argentiventris (Peters) (Perciformes, Lutjanidae), from a Pacific coastal system of Mexico. Infection was most intense on C. viridis. Caligus tenuifurcatus can be distinguished from its closest congener, C. bonito Wilson, by the body proportions and the basal ornamentation of the medial setae of the second exopodal segment of leg 1. Taxonomic illustrations are provided of both female and male. This is the third record of C. tenuifurcatus; hitherto, it was known only as a parasite of the roosterfish Nematistius pectoralis Gill (Perciformes, Nematistiidae) from Panama and the Gulf of California. Hence, the finding of C. tenuifurcatus as a parasite of two species of centropomids and one species of lutjanid represents a significant expansion of the known host range of this copepod in the eastern tropical Pacific.  相似文献   
92.
Aim:  The application of ultrasound may be suitable for evaluating the effects of intestinal cytoskeletal rearrangement of the duodenum and colon as a result of exposure to live Giardia lamblia trophozoites. We studied the sonographic appearance of the duodenum and colon in giardiasis compared with amebiasis and healthy subjects.
Methods:  Sonographic images obtained from 100 consecutive patients with symptomatic giardiasis were compared to those taken from 40 patients with amebiasis and 40 healthy subjects. B-mode ultrasound examination of the duodenum and colon was performed using a 7.5 MHz annular array transducer. Gray scale images with water contrast were acquired.
Results:  Normal duodenum and colon echoanatomy were demonstrated. Giardial lesions of the duodenum and colon were associated with increased wall thickness when compared with healthy subjects ( P  < 0.05). Furthermore, giardial lesions were characterized by increased wall echogenicity, flattening or loss of duodenal folds and/or colonic haustration, hyperechoic floating foci (HFF) demonstrating chaotic motility, increased peri-lesional tissue echogenicity, and altered colonic peristalsis. In amebiasis, focal hyperechoic wall thickening was seen at lesion sites identified as amebomas with increased wall echogenicity, but otherwise normal duodenal folds and colonic haustration. There were no HFF with chaotic motility, rather intestinal contents showed bulk motility in patients with amebiasis. There was no focal colonic wall motion abnormality observed.
Conclusion:  B-mode imaging with water contrast demonstrated details of duodenal and colonic echoanatomy. There were sonographic features of giardial lesions of the duodenum and colon that were distinct from those in amebiasis and healthy subjects.  相似文献   
93.
Imported tropical diseases are among the top three leading causes for morbidity and may affect up to 8% of returning travelers. Because the spectrum of dermatological manifestations seen in travelers is broad, it can be challenging for physicians to recognize and treat such conditions in a timely and efficient manner. Therefore, the present review highlights common imported tropical diseases with a focus on treatment regimens. Specifically, cutaneous larva migrans, myiasis, swimmer's itch, mycetoma, Chagas disease, and leishmaniasis are discussed. As awareness increases among travelers, immigrants, and health care providers regarding imported tropical diseases, early intervention and proper diagnosis can ensue, thus reducing morbidity and mortality in affected individuals.  相似文献   
94.
95.
This review of journal articles and book chapters discusses the health beliefs characteristic of Polynesia and reveals several themes. These are: commonality in health conceptualisations across the cultures of the region which differ from the conceptualisations of biomedicine; the role of the relational self, traditional living and communalism in understanding health; the place of spirituality and religion in health and illness causation; and pluralism and pragmatism in health-seeking behaviour. Suggestions are made as to how awareness of key ideas might contribute to effective planning of health promotion and intervention activities.  相似文献   
96.
97.
Drought exerts a strong influence on tropical forest metabolism, carbon stocks, and ultimately the flux of carbon to the atmosphere. Satellite-based studies have suggested that Amazon forests green up during droughts because of increased sunlight, whereas field studies have reported increased tree mortality during severe droughts. In an effort to reconcile these apparently conflicting findings, we conducted an analysis of climate data, field measurements, and improved satellite-based measures of forest photosynthetic activity. Wet-season precipitation and plant-available water (PAW) decreased over the Amazon Basin from 1996−2005, and photosynthetically active radiation (PAR) and air dryness (expressed as vapor pressure deficit, VPD) increased from 2002–2005. Using improved enhanced vegetation index (EVI) measurements (2000–2008), we show that gross primary productivity (expressed as EVI) declined with VPD and PAW in regions of sparse canopy cover across a wide range of environments for each year of the study. In densely forested areas, no climatic variable adequately explained the Basin-wide interannual variability of EVI. Based on a site-specific study, we show that monthly EVI was relatively insensitive to leaf area index (LAI) but correlated positively with leaf flushing and PAR measured in the field. These findings suggest that production of new leaves, even when unaccompanied by associated changes in LAI, could play an important role in Basin-wide interannual EVI variability. Because EVI variability was greatest in regions of lower PAW, we hypothesize that drought could increase EVI by synchronizing leaf flushing via its effects on leaf bud development.  相似文献   
98.
Studies of influenza-associated hospitalizations in tropical settings are lacking. To increase understanding of the effect of influenza in Singapore, we estimated the age-specific influenza-associated hospitalizations for pneumonia and influenza during 2004–2008 and 2010–2012. The rate of hospitalization was 28.3/100,000 person-years during 2004–2008 and 29.6/100,000 person-years during 2010–2012. The age-specific influenza-associated hospitalization rates followed a J-shaped pattern: rates in persons >75 years of age and in children <6 months of age were >47 times and >26 times higher, respectively, than those for persons 25–44 years of age. Across all ages during these 2 study periods, ≈12% of the hospitalizations for pneumonia and influenza were attributable to influenza. The rates and proportions of hospitalizations for influenza, particularly among the very young and the elderly, are considerable in Singapore and highlight the importance of vaccination in protecting populations at risk.  相似文献   
99.
Prenatal health care counseling is associated with positive health outcomes for mothers and infants. Moreover, pregnant women are considered a vulnerable population at risk of being victims of intimate partner violence. Pregnancy provides a unique opportunity to identify and refer women experiencing intimate partner violence to community resources; however, in prior research, most women reported that their prenatal care providers did not talk to them about intimate partner violence. Given the importance for providers to offer prenatal health care counseling on intimate partner violence, it is concerning that there is scant knowledge on Asian, Native Hawaiian, and other Pacific Islander mothers'' experiences in this area. The study''s objectives were (a) to determine the proportion of mothers who received prenatal health care counseling on intimate partner violence; and, (b) to examine racial differences of those who received prenatal health care counseling on intimate partner violence. Hawai‘i''s Pregnancy Risk Assessment Monitoring System (PRAMS) data from 2004–08 were analyzed for 8,120 mothers with information on receipt of intimate partner violence prenatal health care counseling. Overall, 47.7% of mothers were counseled on intimate partner violence. Compared to Whites, Native Hawaiians, Japanese, Chinese, and Koreans were significantly less likely to report receiving prenatal health care counseling in intimate partner violence, but the opposite association was observed for Samoans. Intimate partner violence continues to be a significant problem for women, thus, this study''s findings may be used as important baseline data to measure the progress made given the implementation of the new Guidelines for Women''s Preventive Services in intimate partner violence screening and counseling.  相似文献   
100.
Objective To conduct a nationwide integrated neglected tropical disease (NTD) prevalence survey to define the need for public health interventions using an innovative mapping protocol. Methods Two villages were selected in every peripheral health unit in endemic districts: 29 districts for schistosomiasis and STH, 15 of them for trachoma. In each village, 15 children aged 6–9 years at a randomly selected school were tested. An additional convenience sample of 35 children aged 1–5 years underwent an eye examination for trachoma. This integrated mapping was followed by a 20‐cluster trachoma survey in each district that surpassed the WHO‐defined threshold of 10% prevalence of trachomatous inflammation‐follicular (TF). Results A total of 1096 villages were surveyed in <6 weeks. The district prevalence of schistosomiasis ranged from 2 to 49% and of STH from 5 to 70%, with prevalence at the village level ranging from 0 to 100% for both diseases. Two districts passed the threshold of 10% for active trachoma, but the cluster survey indicated this was because of misclassification bias and that the real prevalence was <1%. Conclusion Results of this mapping were used by the MoH and partners to plan integrated mass drug administration (MDA). Mass drug administration for trachoma was not implemented as no district passed the threshold requiring public health intervention.  相似文献   
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