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1.
International Journal of Primatology - Information on parasite biodiversity and abundance can improve our understanding of parasitic infections on endangered wildlife, as parasites can affect host...  相似文献   
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Malaria in migrants   总被引:6,自引:0,他引:6  
An increasing proportion of malaria cases in Italy is observed in immigrants revisiting their country of origin, but little specific research work has been carried out in this field. All malaria cases occurring from 1990 to 1998 at the Reference Clinic for Infectious and Tropical Diseases in Brescia were prospectically evaluated to compare clinical outcome in migrant and non-immune cases. No difference was observed between parasitaemia at diagnosis and time to clearance of peripheral parasitaemia. Clinical presentation was milder in migrants than in non-immunes, with an OR for severe malaria of 0.27 (c.i. = 0.09-0.84) (p = 0.01). Fever clearance time was significantly shorter in migrants (3.0 days, SD = 1.2) than in non-immunes (4.3 days, SD = 1.7) (p < 0.001). Among immigrants, the proportion of severe cases was higher in residents since 2 years or less (12.5%) compared to residents since 2 to 5 years (3.3%) and residents since more than 5 years (0.9%) (p = 0.02). The proportion of malaria cases who had used chemoprophylaxis was significantly lower among immigrants (30/272, 11.0%) compared to non-immunes (41/74, 55.4%) (p < 0.001). In a population based malaria KAP analysis among 504 migrants from malaria endemic countries, correct knowledge of malaria risk was reported by 351 (69.5%). Of 170 subjects who reported at least one visit back to the home country, 30 (17.6%) had sought pre-travel advice, 24 (14.1%) had started chemoprophylaxis and 7 (4.1%) had completed it during the last visit. Of 140 migrants who failed to seek pre-travel advice, 73 (52%) were unaware of malaria risk, 56 (40%) did not know how to protect themselves, and 11 (8%) refused to use protective measures. Migrants account for a significant proportion of imported malaria cases in industrialised countries. Clinical presentation is milder compared to non-immune subjects. The proportion of migrants who adopt malaria protective measure while returning home is very low, due to both unawareness of risk and inappropriateness of medical advice.  相似文献   
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Sexual solicitations and initiative (proceptivity, sensu Beach [1976] Horm Behav 7:105-138) are important components of the sexuality of females of many primate species. In the tufted capuchin (Cebus apella), female proceptivity characterizes the species' mating system. In study 1, we defined and discussed 20 behavioral patterns based on the observation of 6 females and 5 males living in two social groups. In study 2, each behavior, including mounting activity, was quantitatively assessed during the periovulatory and nonperiovulatory cycle phases of 4 females, detected on the basis of urinary progestin levels (N = 20 ovulatory cycles, 5 for each female); moreover, we monitored changes in females' social interactions (agonism, grooming activity, and play). Nine of the behaviors typically used by the female during courtship and in sexual interactions showed a dramatic increase during the periovulatory phase. Though males mounted females at an apparently higher rate during the periovulatory than the nonperiovulatory phase, the difference was not significant. However, when adult male mounting is separated into those which occur within play and nonplay contexts, there is a significant periovulatory phase effect for mounts not associated with play. Females groomed adult males at the same rate throughout the cycle. Agonism and play did not show any phase effect; however, females' avoidance of adult males significantly increased during the periovulatory phase. Finally, each female made a statistically different use of the behavioral repertoire by performing some behaviors more than others. This variability among females during courtship calls for further research into whether it affects mating success.  相似文献   
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The recent origin and great evolutionary potential of HIV imply that the virulence of the virus might still be changing, which could greatly affect the future of the pandemic. However, previous studies of time trends of HIV virulence have yielded conflicting results. Here we used an established methodology to assess time trends in the severity (virulence) of untreated HIV infections in a large Italian cohort. We characterized clinical virulence by the decline slope of the CD4 count (n = 1423 patients) and the viral setpoint (n = 785 patients) in untreated patients with sufficient data points. We used linear regression models to detect correlations between the date of diagnosis (ranging 1984–2006) and the virulence markers, controlling for gender, exposure category, age, and CD4 count at entry. The decline slope of the CD4 count and the viral setpoint displayed highly significant correlation with the date of diagnosis pointing in the direction of increasing virulence. A detailed analysis of riskgroups revealed that the epidemics of intravenous drug users started with an apparently less virulent virus, but experienced the strongest trend towards steeper CD4 decline among the major exposure categories. While our study did not allow us to exclude the effect of potential time trends in host factors, our findings are consistent with the hypothesis of increasing HIV virulence. Importantly, the use of an established methodology allowed for a comparison with earlier results, which confirmed that genuine differences exist in the time trends of HIV virulence between different epidemics. We thus conclude that there is not a single global trend of HIV virulence, and results obtained in one epidemic cannot be extrapolated to others. Comparison of discordant patterns between riskgroups and epidemics hints at a converging trend, which might indicate that an optimal level of virulence might exist for the virus.  相似文献   
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A new species of Hycleus belonging to the phaleratus group, and close to Hycleus phaleratus, is described. The new species, Hycleus marcipoli, is distributed in China (Gansu and Taiwan), Laos, and northern Thailand. A key to the Chinese species of this group is presented.  相似文献   
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Helleria brevicornis has a disjunct, peri-Tyrrhenian distribution that mirrors that of several organisms, for which geographic vicariance is invoked, due to the geological events started with the Oligocene split of the Sardo-Corsican microplate from the Pyrenees, and successive separation between Sardinia and Corsica. Molecular phylogenetic analyses demonstrated that such a biogeographic model does not apply to Helleria. The original split of the Sardinian and Corsican lineages originated in the Early Pliocene. Further diversification occurred later. The colonization of the Tuscan archipelago, French, and Italian mainland occurred most recently, but a possible time dependency bias suggests that such colonization was driven by human-transport.  相似文献   
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