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771.
Prescottia mucugensis C. O. Azevedo & van den Berg, a new orchid species from the district of Guiné, municipality of Mucugê, Bahia, Brazil, is
described and illustrated and a key for the related species is presented. 相似文献
772.
Ralph Eric Thijl Vanstreels Rodrigo Hidalgo Friciello Teixeira Luis Carlos Camargo Adauto Luis Veloso Nunes Eliana Reiko Matushima 《Zoo biology》2010,29(5):600-614
Eleven species of Amazon parrots (genus Amazona) are known to occur in Brazil, and nest poaching and illegal traffic pose serious conservation threats to these species. When the illegal owners realize these animals are incompatible with their expectations and lifestyle, or when the police arrests traders and owners, these trafficked animals are often considered unfit for release and sent to local zoos and captive breeders. A retrospective survey of animal and necropsy records from 1986 to 2007 was used to evaluate the impacts of animal traffic on the population composition and mortality patterns of Amazon parrots at the Quinzinho de Barros Municipal Zoological Park, Sorocaba, Brazil. Data were obtained for 374 Amazon parrots of ten Brazilian species, and there was evidence that the studied population could be split into two major groups: a majority belonging to the Amazona aestiva species and a minority belonging to the remaining species. In comparison, the animals of the first group were more frequently admitted from traffic‐related origins (98 vs. 75%), had a shorter lifespan (median 301 days vs. 848 days) and a higher mortality within the first year postadmission (54 vs. 37%), were less likely to receive expensive treatments, and were more frequently housed off‐exhibit. On an average, parrots were found to have a short postadmission lifespan (median 356 days), with 92.5% of the birds dying within their first five years in captivity. The paper discusses the difficult dilemmas these incoming traffic‐related animals pose to zoo management and official anti‐traffic policies. Zoo Biol 29:600–614, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
773.
Fabricia de Souza Predes Maria Aparecida da Silva Diamante Mary Ann Foglio Camila Almeida Camargo Hiroshi Aoyama Silvio Cesar Miranda Bread Cruz Maria Cristina Cintra Gomes Marcondes Heidi Dolder 《Biological trace element research》2014,160(2):250-257
This study was performed to determine the effects of Arctium lappa (Al) to protect against cadmium damage in the rat liver. Male rats received a single i.p. dose of CdCl2 (1.2 mg/kg body weight (BW)) with or without Al extract administered daily by gavage (300 mg/kg BW) for 7 or 56 days. After 7 days, Al caused plasma transaminase activity to diminish in groups Al (glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT)) and CdAl (GPT). After 56 days, GOT and GPT plasma activities were reduced in the Cd group. No alteration in plasma levels of creatinine, total bilirubin, and total protein were observed. GOT liver activity increased in the Cd group. No alteration was observed in superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), and malondialdehyde (MDA) dosage. In the Cd group, hepatocyte proportion decreased and sinusoid capillary proportion increased. In the Al and CdAl groups, the nuclear proportion increased and the cytoplasmic proportion decreased. The hepatocyte nucleus density reduced in Cd and increased in the Al group. After 56 days, there was no alteration in the Cd group. In Al and CdAl groups, the nuclear proportion increased without cytoplasmic proportion variation, but the sinusoid capillary proportion was reduced. The hepatocyte nucleus density decreased in the Cd group and increased in the Al and CdAl groups. In conclusion, the liver function indicators showed that A. lappa protected the liver against cadmium toxicity damage. 相似文献
774.
Erika Berenguer Toby A. Gardner Joice Ferreira Luiz E. O. C. Arag?o Plínio B. Camargo Carlos E. Cerri Mariana Durigan Raimundo C. Oliveira Junior Ima C. G. Vieira Jos Barlow 《PloS one》2015,10(8)
Across the tropics, there is a growing financial investment in activities that aim to reduce emissions from deforestation and forest degradation, such as REDD+. However, most tropical countries lack on-the-ground capacity to conduct reliable and replicable assessments of forest carbon stocks, undermining their ability to secure long-term carbon finance for forest conservation programs. Clear guidance on how to reduce the monetary and time costs of field assessments of forest carbon can help tropical countries to overcome this capacity gap. Here we provide such guidance for cost-effective one-off field assessments of forest carbon stocks. We sampled a total of eight components from four different carbon pools (i.e. aboveground, dead wood, litter and soil) in 224 study plots distributed across two regions of eastern Amazon. For each component we estimated survey costs, contribution to total forest carbon stocks and sensitivity to disturbance. Sampling costs varied thirty-one-fold between the most expensive component, soil, and the least, leaf litter. Large live stems (≥10 cm DBH), which represented only 15% of the overall sampling costs, was by far the most important component to be assessed, as it stores the largest amount of carbon and is highly sensitive to disturbance. If large stems are not taxonomically identified, costs can be reduced by a further 51%, while incurring an error in aboveground carbon estimates of only 5% in primary forests, but 31% in secondary forests. For rapid assessments, necessary to help prioritize locations for carbon- conservation activities, sampling of stems ≥20cm DBH without taxonomic identification can predict with confidence (R2 = 0.85) whether an area is relatively carbon-rich or carbon-poor—an approach that is 74% cheaper than sampling and identifying all the stems ≥10cm DBH. We use these results to evaluate the reliability of forest carbon stock estimates provided by the IPCC and FAO when applied to human-modified forests, and to highlight areas where cost savings in carbon stock assessments could be most easily made. 相似文献
775.
Roma GC Furquim KC Bechara GH Camargo Mathias MI 《Experimental & applied acarology》2011,53(3):287-299
Given the wide use of synthetic chemicals to control ticks, this study evaluated the effects of the permethrin pyrethroid
on oocytes of Rhipicephalus sanguineus fully engorged females in order to examine whether this compound, in addition to the proven neurotoxic effect, also acts
directly on germ cells. The results revealed that permethrin effectively inhibits and/or interrupts the reproductive process
of R. sanguineus. Exposed oocytes exhibited prominent structural changes such as altered shape of cells and germ vesicle (oocyte nucleus),
cytoplasmic vacuolation, and decrease of yolk granules. The composition of the latter, however, was not altered. These findings
confirm those already reported by Roma et al. (Food Chem Toxicol 48:825–830, 2010) demonstrating that permethrin acts on germ
cells of R. sanguineus via direct absorption from the hemolymph by pedicel cells, or by the oocyte plasmic membrane. On the other hand, these results
contradict studies reporting that acaricides act exclusively on the nervous systems of ticks and that all the changes in other
organs are a result from the indirect action of these chemical compounds, because blocking of the nervous system would compromise
the normal metabolism of other organs (dependent on sensory information). 相似文献
776.
We have studied the effects of L-NG-nitro arginine methyl esther (L-NAME), L-arginine (LAR), inhibitor and a donating nitric oxide agent on the alterations of salivary flow, water intake, arterial blood pressure (MAP) and heart rate (HR) induced by the injection pilocarpine into the subfornical organ (SFO). Rats (Holtzman 250-300 g) were anesthetized with 2, 2, 2-tribromoethanol (20 mg/100 kg b. wt.) and a stainless steel cannula were implanted into their SFO. The volume of injection was 0.2 microl. The amount of saliva secretion was studied over a 5-min period. Pilocarpine (40 microg), L-NAME (40 microg) and LAR (30 microg) were used in all experiments for the injection into the SFO. Pilocarpine (10, 20, 40, 80 and 160 microg) injected into SFO elicited a concentration-dependent increase in salivary secretion. L-NAME injected prior to pilocarpine into the SFO increased salivary secretion and water intake due to the effect of pilocarpine. LAR injected prior to pilocarpine into the SFO attenuated the salivary secretion and water intake. Pilocarpine, injected into the SFO increased the MAP and decreased heart rate (HR). L-NAME injected prior to pilocarpine into the SFO potentiated the pressor effect of pilocarpine with a decrease in HR. LAR injected into the SFO prior to pilocarpine attenuated the increase in MAP with no changes in HR. The present study suggests that the SFO nitrergic cells interfere in the cholinergic pathways implicated in the control of salivary secretion, fluid and cardiovascular homeostasis. 相似文献
777.
Tiago Koppe Divair Doneda Marina Siebert Livia Paskulin Matheus Camargo Kristiane Michelin Tirelli Filippo Vairo Liane Daudt Ida Vanessa D. Schwartz 《Genetics and molecular biology》2016,39(1):30-34
The clinical utility of serum ferritin as a biomarker of disease severity and prognosis in Gaucher disease (GD) is still debated. Here, we aimed to evaluate ferritin and its relation to clinicolaboratory parameters of GD patients seen at the Reference Center for Gaucher Disease of Rio Grande do Sul, Brazil, so as to gather evidence on the utility of ferritin as a biomarker of this condition. A retrospective chart review was performed collecting pre-and posttreatment data from GD patients. Eighteen patients with ferritin levels available before and after treatment were included in the study. Nine of these participants were males, and seventeen had type I GD. All patients were given either enzyme replacement (n = 16) or substrate reduction therapy (n = 2), and ferritin was found to decrease from 756 [318-1441] ng/mL at baseline to 521 [227-626] ng/mL (p=0.025) after 28.8 month soft treatment. Serum ferritin levels did not correlate with measures of disease severity, but showed an association with age at onset of treatment (ρ= 0.880; n = 18; p < 0.001). In conclusion, although serum ferritin did not correlate with disease severity, after a median 28.8 months of treatment, clinical outcomes had clearly improved, and ferritin levels had decreased. 相似文献
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