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101.
M G Brand?o T S Grandi E M Rocha D R Sawyer A U Krettli 《Journal of ethnopharmacology》1992,36(2):175-182
Plants traditionally employed for the treatment of malaria in certain areas of Brazil, where this disease is prevalent, were surveyed by interviewing natives and migrants in the Amazon Region. Forty-one plants used for malarial treatment and/or for the related symptoms (fever and liver disorders) were collected and identified. Given the potential of Brazil's forests and medicinal plants, research on traditional plant-based remedies in this country may lead to the development of new drugs. 相似文献
102.
Excitatory amino acids may cause neuronal damage and death in cerebral hypoxia and ischemia, through the activation of different subtypes of glutamate receptors, in particular of the
(NMDA) receptor. In the present work, the effect of hypoxia on the component of the field excitatory postsynaptic potential (fepsp) mediated by the NMDA receptor was studied in the hippocampal CA1 area of the rat. A period of 15 min of hypoxia induced virtual abolition of the NMDA receptor-mediated fepsp and a 94.8 ± 0.7% maximal decrease in the fepsp. A period of 3 min of hypoxia induced a 89.3 ± 12.3% maximal decrease in the NMDA receptor-mediated component of the fepsp and only a 50.8 ± 11.5% maximal decrease in the fepsp. Both periods of hypoxia thus induced a more pronounced depression of the NMDA receptor-mediated component of the fepsp than of the fepsp. We found that 48.5 ± 9.1% decrease (about half of the total decrease) in the NMDA receptor-mediated fepsp, and 51.6 ± 19.6% decrease (approximately all decrease) in the fepsp induced by hypoxia (3 min) were reversed in the presence of the selective adenosine A1 receptor antagonist, 1,3-dipropyl-8-cyclopentylxanthine (DPCPX) (50 nM), and thus likely to be mediated by endogenous adenosine, through the activation of adenosine A1 receptors. On the other hand, under the conditions we assumed to be normoxic in our slices, DPCPX (50 nM) induced a much larger increase in the amplitude of the NMDA receptor-mediated fepsp compared to the increase in the fepsp, which suggest that endogenous adenosine is inhibiting predominantly the NMDA receptor-mediated fepsp under these conditions. Hypoxia markedly decreases the NMDA receptor-mediated fepsp in the hippocampal CA1 area. The contribution of endogenous adenosine to the inhibition of the NMDA receptor-mediated fepsp may be fundamental for its neuroprotective effects. 相似文献
103.
J L Martínez Sande A Amaro Cendón E Blanco Labrador M Pérez Rodríguez A Sánchez Prieto C Iglesias Carre?o M Gil de la Pe?a 《Revista espa?ola de cardiología》1992,45(8):545-548
A 32-year old woman, with endocarditis caused by Streptococcus mitis, and systolic murmur is presented. The Doppler examination was found a systolic gradient of 150 mmHg. Aortography showed a multiple membranous supravalvular aortic stenosis, with aneurysmal dilatation of the left main coronary artery and circumflex artery, associated with bicuspid aortic valve and mild aortic insufficiency. The patient died suddenly by cardiac arrest in stand by to cardiac surgery. Anatomic comprobation was not possible. The coronary artery anomalies associated with the supravalvular aortic stenosis syndrome are reviewed. 相似文献
104.
The trajectory, mass fluxes, and deposition of aerosolized particles in a complex tubular system have been predicted. A procedure based on Lagrangian stochastic modeling is proposed to enable the anticipation of such phenomena, taking advantage of experimental results to characterize the air flow. The predictions have been obtained for pharmaceutical aerosols delivered by dry powder inhalers. A critical assessment of the dispersion model has been carried out using data available in the literature. The procedure assumes a low volume fraction of particles in the simulation of turbulent dispersion, but deposition is physically based on the interaction between the particles and both solid and liquid surfaces. The results were confirmed by experimental tests of powder deposition, run according to the European Pharmacopoeia. A parametric study was also carried out with the aim of providing a more complete evaluation of the model’s performance. The comparison between predictions and experimental results has shown that the model properly describes the deposition of aerosolized particles. 相似文献
105.
Objective: Prevalence of textile dye contact dermatitis (TD‐CD) are lacking in many countries. Our aim is to know the frequency of TD‐CD in three different areas of Spain.
Methods: 100 patients were tested with Spanish standard series and the five most frequent TD in each city. D. Orange 1, D. Orange 3, D. Blue 35, D. Blue 106, D. Blue 124 were included in Murcia and Seville, and the three last and D. Red 1, D. Red 17 in Santiago.
Results: 23/300 (15 women and 8 men) were positives to one or more TD. D. Blue 124 was the most frequent allergen (18/300), followed by D. Blue 106 (17/300). D. Red 1, D. Red 17 and D. Orange 1 were positives in 2/200. D. Orange 3 and D. Blue 35 were positives in 1/200. Eczema was located on hands in 13 cases. Clinical picture was variable. Origin of sensitization was clothing and occupational. Relevance was obtained in 20/23 cases.
Conclusions: The study confirm an high frequency of disperse dye allergy in Spain with a very different prevalence in the three areas: Seville 14%, Murcia 5% and Santiago 4%, that are probably due to social and cultural factors. We recommend the inclusion of D. Blue 106, D. Blue 124, D. Blue 35, D. Red 1, D. Red 17, D. Orange 1 and D. Orange 3 in standard series in order to detect sensitivity to textile colours that is most frequent than previously suspected. 相似文献
Methods: 100 patients were tested with Spanish standard series and the five most frequent TD in each city. D. Orange 1, D. Orange 3, D. Blue 35, D. Blue 106, D. Blue 124 were included in Murcia and Seville, and the three last and D. Red 1, D. Red 17 in Santiago.
Results: 23/300 (15 women and 8 men) were positives to one or more TD. D. Blue 124 was the most frequent allergen (18/300), followed by D. Blue 106 (17/300). D. Red 1, D. Red 17 and D. Orange 1 were positives in 2/200. D. Orange 3 and D. Blue 35 were positives in 1/200. Eczema was located on hands in 13 cases. Clinical picture was variable. Origin of sensitization was clothing and occupational. Relevance was obtained in 20/23 cases.
Conclusions: The study confirm an high frequency of disperse dye allergy in Spain with a very different prevalence in the three areas: Seville 14%, Murcia 5% and Santiago 4%, that are probably due to social and cultural factors. We recommend the inclusion of D. Blue 106, D. Blue 124, D. Blue 35, D. Red 1, D. Red 17, D. Orange 1 and D. Orange 3 in standard series in order to detect sensitivity to textile colours that is most frequent than previously suspected. 相似文献
106.
107.
Using Queueing Theory to Increase the Effectiveness of Emergency Department Provider Staffing 总被引:4,自引:4,他引:0
Linda V. Green PhD João Soares PhD James F. Giglio MD Robert A. Green MD 《Academic emergency medicine》2006,13(1):61-68
Objectives: Significant variation in emergency department (ED) patient arrival rates necessitates the adjustment of staffing patterns to optimize the timely care of patients. This study evaluated the effectiveness of a queueing model in identifying provider staffing patterns to reduce the fraction of patients who leave without being seen. Methods: The authors collected detailed ED arrival data from an urban hospital and used a Lag SIPP queueing analysis to gain insights on how to change provider staffing to decrease the proportion of patients who leave without being seen. The authors then compared this proportion for the same 39‐week period before and after the resulting changes. Results: Despite an increase in arrival volume of 1,078 patients (6.3%), an average increase in provider hours of 12 hours per week (3.1%) resulted in 258 fewer patients who left without being seen. This represents a decrease in the proportion of patients who left without being seen by 22.9%. Restricting attention to a four‐day subset of the week during which there was no increase in total provider hours, a reallocation of providers based on the queueing model resulted in 161 fewer patients who left without being seen (21.7%), despite an additional 548 patients (5.5%) arriving in the second half of the study. Conclusions: Timely access to a provider is a critical dimension of ED quality performance. In an environment in which EDs are often understaffed, analyses of arrival patterns and the use of queueing models can be extremely useful in identifying the most effective allocation of staff. 相似文献
108.
Pamella Huey Mei Wang Marcos Antonio Cenedeze Joo Bosco Pesquero Alvaro Pacheco-Silva Niels Olsen Saraiva Cmara 《International immunopharmacology》2006,6(13-14):1960
Bradykinin B1 receptors are exclusively expressed in inflamed tissues. For this reason, they have been related with the outcomes of several pathologies. Ischemia–reperfusion injury is caused by the activation of inflammatory and cytoprotective genes, such as macrophage chemoattractant protein-1 and heme oxygenase-1, respectively. This study was aimed to analyze the involvement of bradykinin B1 and B2 receptors (B1R and B2R) in tissue response after renal ischemia–reperfusion injury. For that, B1R (B1−/−), B2R (B2−/−) knockout animals and its control (wild-type mice, B1B2+/+) were subjected to renal bilateral ischemia, followed by 24, 48 and 120 h of reperfusion. At these time points, blood serum samples were collected for creatinine and urea dosages. Kidneys were harvested for histology and molecular analyses by real-time PCR. At 24 and 48 h of reperfusion, B1−/− group resulted in the lowest serum creatinine and urea levels, indicating less renal damage, which was proved by renal histology. Renal protection associated with B1−/− mice was also related with higher expression of HO-1 and lower expression of MCP-1. In conclusion, the absence of B1R had a protective role against inflammatory responses developed after renal ischemia–reperfusion injury. 相似文献
109.
Homid Fahandezh-Saddi Díaz Antonio Ríos-Luna Eduardo García-Rey Ma Jesus Rodea Butragueño Manuel Villanueva-Martinez Ma Elena Cantero-Yubero Miguel del Cerro-Gutiérrez 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2007,17(1):105-109
Treatment of chronic osteomyelitis of distal tibia is complex. It often requires the association of antibiotic therapy and a surgical procedure. This consists of exhaustive debridement of infected bone and soft tissue which must have adequate cutaneous coverage and vascular supply which enables creating a barrier to microorganisms and greater resistance to infection. Free or pedicled muscular flaps have been the techniques most often used for this type of lesions. Free flaps require a precise microsurgical technique and prolonged surgery. Pedicled muscular flaps do not provide sufficient coverage and vascularisation of the distal tibia for large size defects. The fasciocutaneous flap has been used for the treatment of coverage defects in the perimalleolar area and the heel. We report the utility of this flap as management of chronic osteomyelitis of the distal third of the tibia with complete healing of the infection and correct cutaneous coverage without complications. 相似文献
110.
Joaquim Ferreira MD João Maia Silva MD Rita Freire BS João Pignatelli MD Leonor Correia Guedes MD Alexandra Feijó MD Mário Miguel Rosa MD Miguel Coelho MD João Costa MD Ana Noronha BS Russell Hewett MD A. Marques Gomes PhD J.L. Cirne de Castro MD Olivier Rascol PhD Cristina Sampaio PhD 《Movement disorders》2007,22(10):1471-1475
Our objective was to evaluate the frequency of neoplastic and preneoplastic skin lesions in Parkinson's disease (PD) patients when compared with an aged-matched population. We performed a cross-sectional survey in PD patients and in an age-matched control group. Patients and controls were examined by a movement disorder specialist and a dermatologist. 150 PD patients and 146 controls were included. Thirty-five PD patients (23.3%) presented skin lesions that could be classified as neoplastic or preneoplastic vs. 20 subjects in the control group (13.7%) (OR 95%, CI 1.92 [1.05, 3.51]). However, this difference lost statistical significance when adjusted for gender (recruitment of controls was matched just for age with an over representation of males in the PD group). Twenty-nine PD patients (19%) presented actinic keratosis and basal cell carcinoma was diagnosed in 4 patients (3%). Although nonconclusive, our results are in agreement with previous studies suggesting an increased risk of skin cancer in PD patients. The frequency of actinic keratosis in PD patients and the associated risk to develop melanoma recommends its screening in future epidemiological studies. 相似文献