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The One Health initiative is a global effort fostering interdisciplinary collaborations to address challenges in human, animal, and environmental health. While One Health has received considerable press, its benefits remain unclear because its effects have not been quantitatively described. We systematically surveyed the published literature and used social network analysis to measure interdisciplinarity in One Health studies constructing dynamic pathogen transmission models. The number of publications fulfilling our search criteria increased by 14.6% per year, which is faster than growth rates for life sciences as a whole and for most biology subdisciplines. Surveyed publications clustered into three communities: one used by ecologists, one used by veterinarians, and a third diverse-authorship community used by population biologists, mathematicians, epidemiologists, and experts in human health. Overlap between these communities increased through time in terms of author number, diversity of co-author affiliations, and diversity of citations. However, communities continue to differ in the systems studied, questions asked, and methods employed. While the infectious disease research community has made significant progress toward integrating its participating disciplines, some segregation—especially along the veterinary/ecological research interface—remains.  相似文献   
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The aim of the study was to investigate the importance of dogs, other domesticated animals and environmental characteristics as risk factors in the epidemiology of American cutaneous leishmaniasis (ACL). A retrospective survey of cases of human ACL in the last ten years and visits to homes in rural locations were carried out in the municipality of Arapongas (southern Brazil) from 2008 to 2010. ACL in humans was significantly associated with a distance of up to 25 meters from the residence to a forest area (OR 5.08; 95% CI: 1.35–21.04), undergrowth area (OR 6.80; 95% CI: 1.69–45.33) and stream (OR 5.87; 95% CI: 1.15–24.59); banana plants near the residence (OR 5.98; 95% CI: 1.49–39.84), absence of ceiling below the roof in the residence (OR 7.30; 95% CI: 1.26–158.1), the dumping of trash in the forest area (OR 26.33; 95% CI: 7.32–93.46) and presence of ACL in dogs in the surrounding area (OR 4.39; 95% CI: 1.37–13.45). In dogs, ACL was associated with a distance of 25 to 50 meters and 51 to 100 meters, respectively, from the residence to a forest area (OR 2.59; 95% CI: 1.08–5.98; OR 3.29; 95% CI: 1.64–6.62), the presence of a stream up to 25 m from the residence (OR 6.23; 95% CI: 2.34–16.54) and banana plants near the residence (OR 0.45; 95% CI: 0.25–0.80). In the locations studied in the municipality of Arapongas (Brazil), the results reveal that canine infection increases the risk of human infection by ACL and the characteristics surrounding the residence increase the risk of infection in both humans and dogs. Thus, integrated environmental management could be a useful measure to avoid contact between humans and phlebotomines.  相似文献   
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Incubating birds must balance their energetic demands with the time needed to provide care to developing embryos. Reduced care by incubating parents can result in longer incubation periods that increase predation risk and potentially influence neonate phenotype. We measured nest temperature, incubation period, and body mass dynamics of female wood ducks Aix sponsa , and used an information-theoretic approach to investigate effects of several explanatory variables on incubation period and thermal characteristics of nests. A model that included clutch size and standard deviation of nest temperature best explained the variation in incubation period. Parameter estimates indicated that incubation period increased with increases in clutch size and standard deviation of nest temperature. Next, we examined relationships between maternal effects and the standard deviation of the nest temperature. The best fitting model included initiation date of incubation. There was little support for including early incubation body mass of females, incubation constancy, and percent change in female body mass in the model. The parameter estimate showed that standard deviation of nest temperature declined as initiation date of incubation advanced. Female body mass at the start of incubation was not related to structural size suggesting that heavy females were in better physical condition than were light females. Heavy females nested earlier and lost more body mass during incubation than light females, but heavy females did not reduce variation in nest temperature to decrease the incubation period. The fact that early nesting females in good physical condition did not shorten incubation periods by keeping nest temperatures less variable could have been due to either energetic limitations or restraints. Experimental manipulations of incubation costs will be needed to distinguish between these hypotheses.  相似文献   
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Polygonum viviparum produces inflorescences which bear both sexual flowers and asexual bulbils in highly variable proportions. This paper investigates the proportion of flowers and bulbils per inflorescence at 12 sites in central Norway. It is shown that there is a 'trade—off between flowers and bulbils so that one cannot be increased without reducing the other'. On average, the balance is tilted in favour of bulbils, but there are significant differences in the proportion of bulbils per inflorescence among sites and among quadrats within 11 of the sites. Of these 11 sites there are 6 in which the proportion of bulbils per inflorescence is correlated with factors of the biotic environment. The factors include: (1) the amount of vascular plant cover, which is negatively correlated with the proportion of bulbils at 2 sites; (2) the cover of P. viviparum , which is positively correlated at 1 site; (3) the number of P. viviparum inflorescences, which is negatively correlated at 3 sites. The results suggest that both intra– and inter–specific factors of the biotic environment play a role in the control of bulbil and flower production in P. viviparum.  相似文献   
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Secondary sexual traits (e.g., horns and antlers) have ecological and evolutionary importance and are of management interest for game species. Yet, how these traits respond to emerging threats like infectious disease remains underexplored. Infectious pneumonia threatens bighorn sheep (Ovis canadensis) populations across North America and we hypothesized it may also reduce horn growth in male sheep. We assess the effect of pneumonia on horn size in male bighorn sheep using 12 herd datasets from across the western United States that had horn growth and disease data. Disease resulted in 12–35% reduction in increment (yearly) length and 3–13% reduction in total horn length in exposed individuals. The disease effect was prolonged when pathogens continued to circulate in sheep populations. Further, disease likely delays the age at which horns reach ¾-curl and prevents achievement of full-curl. This is further evidenced with 6 of the 12 herds experiencing an increase in average age at harvest following die-off events.  相似文献   
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Polymorphism in metabolizing enzymes can influence drug response as well as the risk for adverse drug reactions. Nevertheless, there are still few studies analyzing the consequence of polymorphisms for the Glutathione-S-transferases (GST) gene to drug response in chronic myeloid leukemia (CML). This study reports, the influence of GSTP1*B and GSTT1/GSTM1null polymorphisms in response to imatinib in CML patients in a Brazilian population. One hundred thirty-nine CML patients from the Clinical Hospital of Goiânia, Goiás, Brazil, treated with imatinib were enrolled in this study. Genotyping of GSTT1 and GSTM1 genes deletions were performed by qPCR and of GSTP1 gene was performed by RFLP-PCR. The frequency of GSTP1*1B, GSTT1 and GSTM1null polymorphisms were determined for all patients. The influence of each patient’s genotypes was analyzed with the patient’s response to imatinib treatment. Brazilian CML patients revealed GSTT1 and GSTM1 genes deletions. GSTT1 deletion was found in 19.3% of patients and GSTM1 deletion in 48.7% of patients with CML. GSTT1/GSTM1 deletion was found in 11.7% in Brazilian CML patients. The “G allele” of GSTP1*B, is associated with later cytogenetic response in imatinib therapy. While, the gene presence combined with GG genotype (GSTM1 present/GSTPI-GG) conferred a tend to a later cytogenetic response to patients. GSTP1*B and GSTT1/GSTM1null polymorphisms influence treatment response in CML. Brazilian CML patients presenting GSTP1 AA/AG genotypes alone and in combination with GSTT1 null reach the cytogenetic response faster, while patients presenting GSTP1-GG and GSTMI positive genotypes may take longer to achieve cytogenetic response. As a result, it allows a better prognosis, with the use of an alternative therapy, other than reducing treatment cost.

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Individual host immune responses to infectious agents drive epidemic behavior and are therefore central to understanding and controlling infectious diseases. However, important features of individual immune responses, such as the strength and longevity of immunity, can be challenging to characterize, particularly if they cannot be replicated or controlled in captive environments. Our research on bighorn sheep pneumonia elucidates how individual bighorn sheep respond to infection with pneumonia pathogens by examining the relationship between exposure history and survival in situ. Pneumonia is a poorly understood disease that has impeded the recovery of bighorn sheep (Ovis canadensis) following their widespread extirpation in the 1900s. We analyzed the effects of pneumonia-exposure history on survival of 388 radio-collared adults and 753 ewe-lamb pairs. Results from Cox proportional hazards models suggested that surviving ewes develop protective immunity after exposure, but previous exposure in ewes does not protect their lambs during pneumonia outbreaks. Paradoxically, multiple exposures of ewes to pneumonia were associated with diminished survival of their offspring during pneumonia outbreaks. Although there was support for waning and boosting immunity in ewes, models with consistent immunizing exposure were similarly supported. Translocated animals that had not previously been exposed were more likely to die of pneumonia than residents. These results suggest that pneumonia in bighorn sheep can lead to aging populations of immune adults with limited recruitment. Recovery is unlikely to be enhanced by translocating naïve healthy animals into or near populations infected with pneumonia pathogens.  相似文献   
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Airway smooth muscle (ASM) regulation of airway structure and contractility is critical in fetal/neonatal physiology in health and disease. Fetal lungs experience higher Ca2+ environment that may impact extracellular Ca2+ ([Ca2+]o) sensing receptor (CaSR). Well-known in the parathyroid gland, CaSR is also expressed in late embryonic lung mesenchyme. Using cells from 18-22 week human fetal lungs, we tested the hypothesis that CaSR regulates intracellular Ca2+ ([Ca2+]i) in fetal ASM (fASM). Compared with adult ASM, CaSR expression was higher in fASM, while fluorescence Ca2+ imaging showed that [Ca2+]i was more sensitive to altered [Ca2+]o. The fASM [Ca2+]i responses to histamine were also more sensitive to [Ca2+]o (0–2 mM) compared with an adult, enhanced by calcimimetic R568 but blunted by calcilytic NPS2143. [Ca2+]i was enhanced by endogenous CaSR agonist spermine (again higher sensitivity compared with adult). Inhibition of phospholipase C (U73122; siRNA) or inositol 1,4,5-triphosphate receptor (Xestospongin C) blunted [Ca2+]o sensitivity and R568 effects. NPS2143 potentiated U73122 effects. Store-operated Ca2+ entry was potentiated by R568. Traction force microscopy showed responsiveness of fASM cellular contractility to [Ca2+]o and NPS2143. Separately, fASM proliferation showed sensitivity to [Ca2+]o and NPS2143. These results demonstrate functional CaSR in developing ASM that modulates airway contractility and proliferation.  相似文献   
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