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排序方式: 共有1947条查询结果,搜索用时 46 毫秒
161.
Marino MC de Oliveira CA Rocha AM Rocha GA Clementino NC Antunes LF Oliveira RA Martins AS Del Puerto HL D'Almeida V Galdieri L Pedroso ER Cabral MM Nogueira AM Queiroz DM 《Gut》2007,56(4):469-474
BACKGROUND: Helicobacter pylori gastritis may lead to impairment of the production of pepsinogen and acid, which are essential to cobalamin absorption. In turn, cobalamin deficiency leads to hyperhomocysteinaemia, a risk factor for cardio and cerebrovascular diseases. AIM: To evaluate the effect of H pylori eradication on plasma homocysteine levels in elderly patients. PATIENTS: Sixty-two H pylori-positive elderly patients with cobalamin deficiency were prospectively studied. METHODS: Homocysteine and cobalamin concentrations were determined before, 6 and 12 months after H pylori eradication. RESULTS: Corpus atrophy was observed in a few patients; otherwise, in most of them, the degree of corpus gastritis was moderate to severe. The initial homocysteine mean (SD) levels decreased from 41.0 (27.1) to 21.6 (10.1) micromol/l at the 6 month follow-up (p<0.001) and to 13.1 (3.8) micromol/l 12 months after H pylori eradication (p<0.001). Conversely, initial cobalamin mean levels increased from 145.5 (48.7) pmol/l to 209.8 (87.1) pmol/l and to 271.2 (140.8) pmol/l, 6 and 12 months after treatment, respectively (p<0.001 for both). Although the erythrocyte mean corpuscular volume was within reference intervals, it decreased significantly 6 (p = 0.002) and 12 (p<0.001) months after treatment. CONCLUSIONS: The results of the current study demonstrated that the eradication of H pylori in elderly patients with cobalamin deficiency is followed by increasing of cobalamin and decreasing of homocysteine blood levels. 相似文献
162.
163.
Fanelli A Cabral AL Neder JA Martins MA Carvalho CR 《Medicine and science in sports and exercise》2007,39(9):1474-1480
PURPOSE: Aerobic training has been shown to be effective in improving cardiopulmonary fitness in asthmatic children. However, the actual impact of physical training on clinical indicators of disease control remains controversial. METHODS: Thirty-eight children with moderate to severe persistent asthma were randomly assigned to control (N=17) and training (N=21) groups. Spirometry, exercise challenge, and maximum incremental cardiopulmonary exercise tests were performed 16 wk apart. Daily doses of inhaled steroids and Pediatric Asthma Quality of Life Questionnaire (PAQLQ) scores were also recorded. RESULTS: Physical training was associated with significant improvements in physiological variables at peak and submaximal exercise (P<0.05); in contrast, no significant changes were found in controls. Severity of exercise-induced bronchoconstriction (EIB) and postexercise breathlessness were significantly lessened in trained patients; improvement in fitness and EIB, however, were not linearly related (P>0.05). In addition, PAQLQ scores improved only in trained children (P<0.01). Daily doses of inhaled steroids were reduced in trained patients (52%), but they remained unchanged or increased in controls (70.6%) (P=0.07). CONCLUSION: Supervised exercise training might be associated with beneficial effects on disease control and quality of life in asthmatic children. These data suggest an adjunct role of physical conditioning on clinical management of patients with more advanced disease. 相似文献
164.
Soto-Montenegro ML Vaquero JJ Arango C Ricaurte G García-Barreno P Desco M 《European journal of nuclear medicine and molecular imaging》2007,34(6):916-925
Purpose This study was designed to assess changes in glucose metabolism in rats administered single or repeated doses of MDMA.
Methods Two different experiments were performed: (1) A single-dose study with four groups receiving 20 mg/kg, 40 mg/kg, saline or
heat, and (2) a repeated-dose study with two groups receiving three doses, at intervals of 2 h, of 5 mg/kg or saline. Rats
were imaged using a dedicated small-animal PET scanner 1 h after single-dose administration or 7 days after repeated doses.
Glucose metabolism was measured in 12 cerebral regions of interest. Rectal temperature and blood glucose were monitored.
Results Peak body temperature was reached 1 h after MDMA administration. Blood glucose levels decreased significantly after MDMA administration.
In the single-dose experiment, brain glucose metabolism showed hyperactivation in cerebellum and hypo-activation in the hippocampus,
amygdala and auditory cortex. In the repeated-dose experiment, brain glucose metabolism did not show any significant change
at day 7.
Conclusion These results are the first to indicate that MDMA has the potential to produce significant hypoglycaemia. In addition, they
show that MDMA alters glucose metabolism in components of the motor, limbic and somatosensory systems acutely but not on a
long-term basis. 相似文献
165.
Oliveira CR dos Santos FA Nogueira CS Mainardes EJ 《Anesthesia and analgesia》2007,104(6):1561-2, table of contents
Congenital insensitivity to pain with anhidrosis (CIPA) is a rare, hereditary, autonomic recessive disorder. The inability to perceive pain results from loss of nociceptive afferents, while anhidrosis is caused by loss of innervation to the sweat glands. Insensitivity to pain and mental retardation lead to self-inflicted injuries, corneal lacerations, painless bony fractures, joint deformities with consequent chronic osteomyelitis, and septic arthritis. There are only a few reports on the anesthetic management for patients with CIPA. We describe the anesthetic management of a young woman with CIPA receiving bilateral arthrodesis of the ankle. 相似文献
166.
Antimalarial activity of betulinic acid and derivatives in vitro against Plasmodium falciparum and in vivo in P. berghei-infected mice 总被引:1,自引:1,他引:0
Matheus Santos de Sá José Fernando Oliveira Costa Antoniana Ursine Krettli Mariano Gustavo Zalis Gabriela Lemos de Azevedo Maia Ivana Maria Fechine Sette Celso de Amorim Camara José Maria Barbosa Filho Ana Maria Giulietti-Harley Ricardo Ribeiro dos Santos Milena Botelho Pereira Soares 《Parasitology research》2009,105(1):275-279
Malaria is one of the most important tropical diseases and mainly affects populations living in developing countries. Reduced
sensitivity of Plasmodium sp. to formerly recommended antimalarial drugs places an increasing burden on malaria control programs as well as on national
health systems in endemic countries. The present study aims to evaluate the antimalarial activity of betulinic acid and its
derivative compounds, betulonic acid, betulinic acid acetate, betulinic acid methyl ester, and betulinic acid methyl ester
acetate. These substances showed antiplasmodial activity against chloroquine-resistant Plasmodium falciparum parasites in vitro, with IC50 values of 9.89, 10.01, 5.99, 51.58, and 45.79 μM, respectively. Mice infected with Plasmodium berghei and treated with betulinic acid acetate had a dose-dependent reduction of parasitemia. Our results indicate that betulinic
acid and its derivative compounds are candidates for the development of new antimalarial drugs. 相似文献
167.
Marta Regina Santin Adriana Oliveira dos Santos Celso Vataru Nakamura Benedito Prado Dias Filho Izabel Cristina Piloto Ferreira Tania Ueda-Nakamura 《Parasitology research》2009,105(6):1489-1496
Leishmaniasis causes considerable mortality throughout the world, affecting more than 12 million people. Cymbopogon citratus (DC) Stapf, Family Poaceae, is a widely used herb in tropical countries and is also known as a source of ethnomedicines.
In this study, the inhibitory effect and the morphological and ultrastructural alterations on Leishmania amazonensis by the essential oil (EO) of C. citratus and its main constituent, citral, were evaluated. The results showed that the antiproliferative activity of EO on promastigotes
and axenic amastigotes, and intracellular amastigote forms of L. amazonensis was significantly better than citral, and indicated a dose-dependent effect. Neither compound showed a cytotoxic effect on
macrophage strain J774G8. The promastigote forms of L. amazonensis underwent remarkable morphological and ultrastructural alterations compared with untreated cultures. These alterations were
visible by light, scanning, and transmission electron microscopy of promastigotes treated with EO and citral at concentrations
corresponding to the IC50 (1.7 and 8.0 μg/ml) and IC90 (3.2 and 25 μg/ml), respectively, after 72 h of incubation. This study revealed that citral-rich essential oil from C. citratus has promising antileishmanial properties, and is a good candidate for further research to develop a new anti-protozoan drug. 相似文献
168.
Adriano Meneghini Celso Ferreira Luiz Carlos de Abreu Vitor E. Valenti Marcelo Ferreira Celso F. Filho Neif Murad 《Clinics (S?o Paulo, Brazil)》2009,64(9):921-926
OBJECTIVES
Memantine is an N-methyl-d-aspartate (NMDA) glutamate receptor antagonist used to treat Alzheimer’s disease. Previous studies have suggested that receptor blockers act as neuroprotective agents; however, no study has specifically investigated the impact that these drugs have on the heart. We sought to evaluate the effects of memantine on nuclear size reduction in cardiac cells exposed to cold stress.METHOD
We used male EPM-Wistar rats (n=40) divided into 4 groups: 1) Matched control (CON); 2) Memantine-treated rats (MEM); 3) Rats undergoing induced hypothermia (IH) and 4) Rats undergoing induced hypothermia that were also treated with memantine (IHM). Animals in the MEM and IHM groups were treated by oral gavage administration of 20 mg/kg/day memantine over an eight-day period. Animals in the IH and IHM groups were submitted to 4 hours of hypothermia in a controlled environment with a temperature of − 8°C on the last day of the study.RESULTS
The MEM group had the largest cardiomyocyte nuclear size (151 ± 3.5 μm3 vs. CON: 142 ± 2.3 μm3; p<0.05), while the IH group had the smallest mean value of nuclear size. The nuclear size of the IHM group was preserved (125 ± 2.9 μm3) compared to the IH group (108 ± 1.7 μm3; p<0.05).CONCLUSION
Memantine prevented the nuclear size reduction of cardiomyocytes in rats exposed to cold stress. 相似文献169.
Celso A. Rodrigues de Almeida CostaDaniele Oliveira Kohn Valéria Martins de LimaAndré Costa Gargano Jorge Camilo FlórioMirtes Costa 《Journal of ethnopharmacology》2011,137(1):828-836
Ethnopharmacological relevance
The essential oil (EO) from Cymbopogon citratus (DC) Stapf is reported to have a wide range of biological activities and is widely used in traditional medicine as an infusion or decoction. However, despite this widely use, there are few controlled studies confirming its biological activity in central nervous system.Materials and methods
The anxiolytic-like activity of the EO was investigated in light/dark box (LDB) and marble-burying test (MBT) and the antidepressant activity was investigated in forced-swimming test (FST) in mice. Flumazenil, a competitive antagonist of benzodiazepine binding and the selective 5-HT1A receptor antagonist WAY100635 was used in experimental procedures to determine the action mechanism of EO. To exclude any false positive results in experimental procedures, mice were submitted to the rota-rod test. We also quantified some neurotransmitters at specific brain regions after EO oral acute treatment.Results
The present work found anxiolytic-like activity of the EO at the dose of 10 mg/kg in a LDB. Flumazenil, but not WAY100635, was able to reverse the effect of the EO in the LDB, indicating that the EO activity occurs via the GABAA receptor-benzodiazepine complex. Only at higher doses did the EO potentiate diethyl-ether-induced sleeping time in mice. In the FST and MBT, EO showed no effect. Finally, the increase in time spent in the light chamber, demonstrated by concomitant treatment with ineffective doses of diazepam (DZP) and the EO, revealed a synergistic effect of the two compounds. The lack of activity after long-term treatment in the LDB test might be related to tolerance induction, even in the DZP-treated group. Furthermore, there were no significant differences between groups after either acute or repeated treatments with the EO in the rota-rod test. Neurochemical evaluation showed no amendments in neurotransmitter levels evaluated in cortex, striatum, pons, and hypothalamus.Conclusions
The results corroborate the use of Cymbopogon citratus in folk medicine and suggest that the anxiolytic-like effect of its EO is mediated by the GABAA receptor-benzodiazepine complex. 相似文献170.
Coelho-de-Souza FH Rocha Ada C Rubini A Klein-Júnior CA Demarco FF 《Brazilian dental journal》2010,21(4):327-331
The aim of this study was to evaluate the fracture strength of teeth with different cavosurface margin cavity preparations and restored with composite resin and different adhesive systems. Eighty premolars were randomly divided in 8 groups, as follow: G1- sound teeth; G2- MOD preparation (no restoration); G3- Adper Single Bond without bevel preparation (butt joint); G4- Adper Single Bond with bevel preparation; G5- Adper Single Bond with chamfer preparation; G6- Clearfil SE Bond without bevel (butt joint); G7- Clearfil SE Bond with bevel preparation; G8- Clearfil SE Bond with chamfer preparation. The adhesive systems were applied according to manufacturers' instructions. Composite resin (Filtek Z250) was incrementally placed in all cavities. After 24 h, the specimens were tested in a universal testing machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test (fracture strength) and Fisher's exact test (fracture pattern). The confidence level was set at 95% for all tests. Prepared and non-restored teeth showed the worst performance and G4 exhibited the highest fracture strength among all groups (p<0.05). In conclusion, all restorative treatments were able to recover the fracture strength of non-restored teeth to levels similar to those of sound teeth. Using a total-etch adhesive system with bevel preparation significantly improved the resistance to fracture. 相似文献