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排序方式: 共有9845条查询结果,搜索用时 11 毫秒
81.
Jorge MP Madjarof C Gois Ruiz AL Fernandes AT Ferreira Rodrigues RA de Oliveira Sousa IM Foglio MA de Carvalho JE 《Journal of ethnopharmacology》2008,118(3):361-366
ETHNOPHARMACOLOGICAL RELEVANCE: Arrabidaea chica Verlot. (Bignoniaceae), popularly known as Crajiru, has been traditionally used as wound healing agent. AIM OF THE STUDY: Investigate in vitro and in vivo healing properties of Arrabidaea chica leaves extract (AC). MATERIALS AND METHODS: AC was evaluated in vitro in fibroblast growth stimulation (0.25-250 microg/mL) and collagen production stimulation (250 microg/mL) assays. Allantoin (0.25-250 microg/mL) and vitamin C (25 microg/mL) were used as controls respectively. DPPH and Folin-Ciocalteau assays were used for antioxidant evaluation, using trolox (0.25-250 microg/mL) as reference antioxidant. To study wound healing properties in rats, AC (100mg/mL, 200 microL/wound/day) was topically administered during 10 days and wound area was evaluated every day. Allantoin (100mg/mL, 200 microL/wound/day) was used as standard drug. After treatment, wound sites were removed for histopathological analysis and total collagen determination. RESULTS: AC stimulated fibroblast growth in a concentration dependent way (EC50=30 microg/mL), increased in vitro collagen production and demonstrated moderate antioxidant capacity. In vivo, AC reduced wound size in 96%, whereas saline group showed only 36% wound healing. CONCLUSION: AC efficiency seems to involve fibroblast growing stimulus and collagen synthesis both in vitro and in vivo, beyond moderate scavenging activity, corroborating Crajiru folk use. 相似文献
82.
Moraes Tde M Rodrigues CM Kushima H Bauab TM Villegas W Pellizzon CH Brito AR Hiruma-Lima CA 《Journal of ethnopharmacology》2008,120(2):161-168
Ethnopharmacological relevance
Mangaba (Hancornia speciosa Gomez) is a medicinal plant frequently cited in ethnopharmacological inventories of the central region of Brazil against gastrointestinal disorders such as diarrhoea, ulcer, gastritis and stomachache.Aim of the study
The hydroalcoholic extract (HE) and infusion (BI) of Hancornia speciosa bark were investigated for their ability to prevent and heal rodent gastric ulcer.Materials and methods
The preventive and healing action of both preparations of Hancornia speciosa were evaluated in experimental models in rodents that simulated this disease in human gastric mucosa.Results
BI did not exert gastroprotective effect, in contrast to HE (500 mg/kg, p.o.) that decreased (p < 0.05) the severity of gastric damage induced by HCl/ethanol (52%), indomethacin/bethanechol (51%), stress (52%) or pylorus ligature experiments (54%). HE increased (p < 0.05) the pH and decreased acid output of gastric juice. This extract promoted increase of mucus amount (3.62 mg/wt. tissue vs. 5.81 mg/wt. tissue), healing action (67%) and displayed anti-Helicobacter pylori effect.Conclusions
The antiulcer action of Hancornia speciosa resulted in increase of gastric mucus formation and antioxidant properties of polymeric proanthocyanidins present in the bark composition of this medicinal plant. 相似文献83.
Rodrigues E Gianfratti B Tabach R Negri G Mendes FR 《Phytotherapy research : PTR》2008,22(9):1248-1255
During an ethnopharmacological survey carried out among some Quilombolas living in Brazil, 48 plants with possible central nervous system (CNS) action were cited. A mixture of nine plants, known as 'Tira-capeta' (Removing the Devil) cigarette, has been utilized for years as a tonic for the brain. The effects observed after consuming this cigarette are: dizziness, lightness sensation, humor changes, yawns, heavy eyes, hunger, sleep and relaxation. This study aimed to verify the effects of a hydroalcohol extract of 'Tira-capeta' cigarette (ETC), as well as to evaluate the phytochemical profile. The phytochemical screening carried out through characterization reactions, thin layer chromatography and high efficiency liquid chromatography indicated the presence of tannins, phenolic acids, flavonoids, saponins and alkaloids; tannins and phenolic acids being the principal constituents. The pharmacological tests showed that ETC induced a biphasic effect, with intense initial stimulation of the CNS, followed by a general depressor state; decreased the latency for sleeping and increased the total sleeping time (50, 100 and 500 mg/kg), without causing prejudice in motor coordination (doses up to 200 mg/kg); induced catalepsy in mice, verified 10 and 50 min after drug administration (500 mg/kg). Also, no anxiolytic or anxiogenic effects were verified in rats submitted to the elevated plus-maze. 相似文献
84.
Paulo A Martins S Branco P Dias T Borges C Rodrigues AI Costa Mdo C Teixeira A Mota-Filipe H 《Phytotherapy research : PTR》2008,22(4):539-543
The effect of an aqueous extract of Pterospartum tridentatum on the blood glucose levels of normal Wistar rats was investigated in a situation of oral glucose challenge. The extract at 300 mg/kg showed an antihyperglycaemic effect in the first 30 min after glucose challenge but then the blood glucose levels rose above those of the control group, indicating the presence of compounds with different effects on glucose tolerance. Nine compounds of isoflavone and flavonol skeletons were identified in the extract by HPLC-ESI-MS(n), four of them being identified for the first time in this species. The isoflavone sissotrin and the flavonol derivative, isoquercitrin, were selected for the oral glucose tolerance test. Isoquercitrin (100 mg/kg) showed time-dependent antihyperglycaemic activity by delaying the post-oral glucose load glycaemic peak at 30 min, as did the sodium-dependent glucose transporter inhibitor phloridzin (100 mg/kg). In contrast, sissotrin (100 mg/kg) showed an opposite effect, impairing glucose tolerance. In conclusion, these preliminary results indicate that the effect of the extract on blood glucose may be either antihyperglycaemic or hyperglycaemic. Additionally, as far as is known, these are the first in vivo results on the acute antihyperglycaemic potential of isoquercitrin. 相似文献
85.
86.
Cabrita S Rodrigues H Abreu R Martins M Teixeira L Marques C Mota F de Oliveira CF 《European journal of gynaecological oncology》2008,29(2):135-137
PURPOSE OF INVESTIGATION: Magnetic resonance imaging (MRI) has emerged as an important imaging modality in the evaluation of the extension of endometrial carcinoma which is essential in planning treatment and predicting prognosis. This study aimed to assess the value of MRI in the preoperative staging of endometrial carcinoma. METHODS: We included in this study 162 patients with a histological diagnosis of endometrial carcinoma who underwent MRI pelvic imaging and surgical staging. MRI images were compared with pathological findings to measure MRI's sensitivity, specificity, positive and negative predictive values and diagnostic accuracy in what concerns myometrial, cervical and lymph node invasion. RESULTS: MRI differentiation of deep myometrial invasion from superficial disease agreed with pathological findings in 77% of cases, with a sensitivity of 83%, a specificity of 72% and a diagnostic accuracy of 77%. Concerning cervical invasion, MRI had a sensitivity, specificity and diagnostic accuracy of 42%, 92%, 81% respectively. In assessing lymph node invasion, MRI presented a sensitivity of just 17%, a specificity of 99% and a diagnostic accuracy of 89%. CONCLUSION: Our study confirmed the high accuracy of MRI imaging in assessing myometrial and cervical invasion in endometrial carcinoma. When evaluating lymph node invasion, micrometastases are responsible for the low sensitivy of MRI. 相似文献
87.
88.
Luís Marangoni Júnior Camila Rodrigues Fozzatti Ewelina Jamrz Ronirik Pioli Vieira Rosa Maria Vercelino Alves 《Materials》2022,15(11)
Blend films based on sodium alginate (SA) and citrus pectin (P) reinforced with different concentrations of SiO2 (0–10% w/w) were developed in this study. From the morphological (SEM) and structural (FT-IR) evaluation, it was verified that the incorporation of the reinforcing agent did not drastically modify the microstructure of the films, nor did new chemical bonds form. However, the XRD results suggested a slight reduction in the crystallinities of the blends by the incorporation of SiO2. Among the formulations prepared, the addition of a 5% reinforcing agent was responsible for the simultaneous improvement of mechanical and barrier properties. Comparing the control sample (SA/P) with the SA/P/5.0%SiO2 film, the tensile strength increased from 27.7 ± 3.7 to 40.6 ± 4.5 MPa, and the water-vapor transmission rate decreased from 319.8 ± 38.7 to 288.9 ± 23.5 g m−2 day−1. Therefore, SiO2, as a reinforcing agent in SA/P blends, represents a simple and effective strategy for improving the properties of biopolymer-based films in applications, such as packaging. 相似文献
89.
Enio R Vasques Estela RR Figueira Joel A Rocha-Filho Cinthia Lanchotte Jorge LS Ximenes Helena B Nader Ivarne LS Tersariol Marcelo A Lima Tiago Rodrigues José EM Cunha Eleazar Chaib Luiz AC D'Albuquerque Flávio HF Galv?o 《Hepatobiliary & pancreatic diseases international : HBPD INT》2022,21(2):190-192
<正>To the Editor:Ischemia-reperfusion injury following surgery and transplantation can lead to irreversible multiorgan failure.Intracellular calcium overload is associated to cellular death during ischemiareperfusion.A recently discovered heparin fragment (HF),trisulfated disaccharide (TD),that acts on sodium-calcium exchanger(NCX) decreasing intracellular Ca2+,showed effectiveness on protecting hepatocytes from ischemia-reperfusion injury [1], 相似文献