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The localisation of the vacuolar proton pump (V-H+ -ATPase) and the enzyme carbonic anhydrase II (CAII) was investigated in the human eccrine sweat gland employing standard immunohistochemical techniques after antigen retrieval using microwave heat treatment and high pressure. The high-pressure antigen retrieval unmasked the presence of V-H+ -ATPase in the clear cells of the secretory coil, with a distribution similar to that previously observed for CAII. However, the dark cells were unreactive to both antibodies. In addition, heat and high-pressure antigen retrieval demonstrated the presence of CAII in the apical zone of luminal cells of the reabsorptive duct, a location not previously reported. The localisation of V-H+ -ATPase and CAII in the secretory coil clear cells suggests that the formation of HCO3- and H+ by carbonic anhydrase II and the transport of H+ by V-H+ -ATPase may play an role in sweat fluid secretion. Their presence at the apex of the duct cells indicates involvement in ductal ion reabsorption.  相似文献   
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SYNOPSIS. Data for host and geographic distribution are listed for Pirhemocyton and for apparently similar infections of poikilothermic vertebrates. The list was compiled from published accounts of Pirhemocyton, Toddia, Cytamoeba, Bertarellia , Piscine erythrocytic necrosis, Immanoplasma, Haematractidium, Sauroplasma, Sauromella, Serpentoplasma, Tunetella, Haemohormidium and unnamed infections. New records are included for Pirhemocyton and Haematractidium. The probability that some may be viruses and not protozoa is discussed; Haematractidium is shown by electron microscopy to be a eukaryote whereas Immanoplasma is not a eukaryote.  相似文献   
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Abstract Urban environments are highly modified with unique assemblages of bird species. Much of the research on urban bird assemblages comes from the northern hemisphere. Southern hemisphere bird assemblages differ from northern hemisphere assemblages in that they contain a large proportion of nectarivores. In this study we focus on bird use of street trees in Australia. We investigate the relative influence of tree species (plane tree, Platanus x acerifolia; red gums, Eucalyptus camaldulensis; jacaranda, Jacaranda mimosifolia; bottlebrush, Callistemon citrinus), season and the environment surrounding street trees, on the abundance and species richness of birds in Adelaide, South Australia. Our study considers birds in terms of granivore, nectarivore and insectivore trophic guilds. Nectarivores accounted for the greatest proportion of observations, in terms of abundance, in each of the tree species investigated. Species of street tree was a significant influence on bird use of the trees for all birds and each dietary guild. Red gums were used more than the other tree species by nectarivores, while plane trees were used more than the other trees by insectivores. Use of the tree species by granivores varied with the season. The measures of the environment surrounding street trees were largely unimportant with the exception of traffic for nectarivores in some cases. Urban avifauna use street trees and the species of tree will strongly influence its use by birds. However, the pattern of use of street tree species varied at different times of year and differed between different trophic guilds of birds. The dominance of nectarivores in the southern avifauna will likely produce different patterns of urban environment use to northern hemisphere avifaunas.  相似文献   
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The incorporation of dextran into broth for the detection of bacteraemia by conductance monitoring is recommended to eliminate the effect of sedimenting blood cells which may mask early signals from bacteria. Broth containing ten times the recommended concentration of dextran was tested with a wide range of bacteria without demonstrating any reduction in growth or rate of change of conductance.  相似文献   
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Males and females differ in body size in many animals, but the direction and extent of this sexual size dimorphism (SSD) varies widely. Males are larger than females in most lizards of the iguanian clade, which includes dragon lizards (Agamidae). I tested whether the male larger pattern of SSD in the peninsula dragon lizard, Ctenophorus fionni, is a result of sexual selection for large male size or relatively higher mortality among females. Data on growth and survivorship were collected from wild lizards during 1991–1994. The likelihood of differential predation between males and females was assessed by exposing pairs of male and female lizards to a predator in captivity, and by comparing the frequency of tail damage in wild‐caught males and females. Male and female C. fionni grew at the same rate, but males grew for longer than females and reached a larger asymptotic size (87 mm vs. 78 mm). Large males were under‐represented in the population because they suffered higher mortality than females. Predation may account for some of this male‐biased mortality. The male‐biased SSD in C. fionni resulted from differences in growth pattern between the sexes. The male‐biased SSD was not the result of proximate factors reducing female body size. Indeed SSD in this species remained male‐biased despite high mortality among large males. SSD in C. fionni is consistent with the ultimate explanation of sexual selection for large body size in males.  相似文献   
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Background

Venous thromboembolism (VTE) is a common preventable cause of mortality in hospitalized medical patients. Despite rigorous randomized trials generating strong recommendations for anticoagulant use to prevent VTE, nearly 40% of medical patients receive inappropriate thromboprophylaxis. Knowledge-translation strategies are needed to bridge this gap.

Methods

We conducted a 16-week pilot cluster randomized controlled trial (RCT) to determine the proportion of medical patients that were appropriately managed for thromboprophylaxis (according to the American College of Chest Physician guidelines) within 24 hours of admission, through the use of a multicomponent knowledge-translation intervention. Our primary goal was to determine the feasibility of conducting this study on a larger scale. The intervention comprised clinician education, a paper-based VTE risk assessment algorithm, printed physicians’ orders, and audit and feedback sessions. Medical wards at six hospitals (representing clusters) in Ontario, Canada were included; three were randomized to the multicomponent intervention and three to usual care (i.e., no active strategies for thromboprophylaxis in place). Blinding was not used.

Results

A total of 2,611 patients (1,154 in the intervention and 1,457 in the control group) were eligible and included in the analysis. This multicomponent intervention did not lead to a significant difference in appropriate VTE prophylaxis rates between intervention and control hospitals (appropriate management rate odds ratio = 0.80; 95% confidence interval: 0.50, 1.28; p = 0.36; intra-class correlation coefficient: 0.022), and thus was not considered feasible. Major barriers to effective knowledge translation were poor attendance by clinical staff at education and feedback sessions, difficulty locating preprinted orders, and lack of involvement by clinical and administrative leaders. We identified several factors that may increase uptake of a VTE prophylaxis strategy, including local champions, support from clinical and administrative leaders, mandatory use, and a simple, clinically relevant risk assessment tool.

Conclusions

Hospitals allocated to our multicomponent intervention did not have a higher rate of medical inpatients appropriately managed for thromboprophylaxis than did hospitals that were not allocated to this strategy.  相似文献   
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