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排序方式: 共有5220条查询结果,搜索用时 11 毫秒
41.
Veridiana M Rodrigues Silvana Marcussi Rafael S Cambraia Ana L de Araújo Natael R Malta-Neto Amélia Hamaguchi Eloísa A V Ferro Maria I Homsi-Brandeburgo José R Giglio Andreimar M Soares 《Toxicon》2004,44(3):305-314
Two basic myotoxic PLA(2)s, namely BnpTX-I and II, were isolated from Bothrops neuwiedi pauloensis snake venom through three chromatographic steps: ion-exchange chromatography on CM-Sepharose, gel filtration on Sephadex G-50 and reverse phase HPLC on a C18 column. Both PLA(2)s showed a M(r) around 14,000 for the monomer and 28,000 for the dimer (as estimated by SDS-PAGE), pI approximately 7.8 and approximately 121 amino acid residues cross-linked by seven disulfide bonds. The N-terminal sequences revealed significant homology with Asp49 basic myotoxic PLA(2)s from other snake venoms. The catalytic and anticoagulant activities of BnpTX-I were higher than those of BnpTX-II. Both were able to induce cytotoxicity in vitro, as well as, myotoxicity, edema and lethality in mice. BnpTX-I also induced neurotoxic effect on mouse neuromuscular preparations and bactericidal activity on Eschericia coli and Staphylococcus aureus. After chemical modification of BnpTX-I with BPB or incubation with EDTA or Mn(2+) ions, the catalytic activity was completely abolished, while the toxic and pharmacological activities were partially reduced. Interaction with heparin inhibited the cytotoxic and bactericidal effects. Anti-BthTX-I, anti-BthTX-II and anti-115-129-C terminal antibodies strongly recognize both BnpTX-I and II. It is shown that the neurotoxic effect induced by B. neuwiedi pauloensis venom is due to the presence of myotoxic PLA(2)s. The data also corroborate the hypothesis of a partial dissociation between toxic and enzymatic domains. In addition, BnpTX-I displays a heparin binding C-terminal region, which is probably responsible for the cytotoxic and bactericidal effects. 相似文献
42.
Patrícia Gon?alves Pinheiro Gilvandete Maria Pinheiro Santiago Francisco Erivaldo Freitas da Silva Ana Carolina Justino de Araújo Cícera Rejane Tavares de Oliveira Priscilla Ramos Freitas Janaína Esmeraldo Rocha JoséBezerra de Araújo Neto Maria Milene Costa da Silva Saulo Relison Tintino Irwin Rose Alencar de Menezes Henrique Douglas Melo Coutinho JoséGalberto Martins da Costa 《Asian Pacific Journal of Tropical Biomedicine》2021,(9):405-413
Objective: To evaluate the inhibitory activity of ferulic acid and four of its esterified derivatives (methyl, ethyl, propyl, and butyl) against resistance mech... 相似文献
43.
Tatiane Teixeira Oliveira Keina Maciele Campos Ana Tereza Cerqueira-Lima Tamires Cana Brasil Carneiro Eudes da Silva Velozo Ingrid Christie Alexandrino Ribeiro Melo Eugênia Abrantes Figueiredo Eduardo de Jesus Oliveira Darizy Flávia Silva Amorim de Vasconcelos Lain Carlos Pontes-de-Carvalho Neuza Maria Alcantara-Neves Camila Alexandrina Figueiredo 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2015,23(1)
Background
Asthma is an inflammatory condition characterized by airway hyperresponsiveness and chronic inflammation. The resolution of inflammation is an essential process to treat this condition. In this study we investigated the effect of Allium cepa L. extract (AcE) and quercetin (Qt) on cytokine and on smooth muscle contraction in vitro and its therapeutic potential in a murine model of asthma.Methods
AcE was obtained by maceration of Allium cepa L. and it was standardized in terms of quercetin concentration using high performance liquid chromatography (HPLC). In vitro, using AcE 10, 100 or 1000 μg/ml or Qt 3.5, 7.5, 15 μg/ml, we measured the concentration of cytokines in spleen cell culture supernatants, and the ability to relax tracheal smooth muscle from A/J mice. In vivo, Blomia tropicalis (BT)-sensitized A/J mice were treated with AcE 100, 1000 mg/kg or 30 mg/kg Qt. We measured cell influx in bronchoalveolar lavage (BAL), eosinophil peroxidase (EPO) in lungs, serum levels of Bt-specific IgE, cytokines levels in BAL, and lung histology.Results
We observed a reduction in the production of inflammatory cytokines, a relaxation of tracheal rings, and a reduction in total number of cells in BAL and EPO in lungs by treatment with AcE or Qt.Conclusion
AcE and Qt have potential as antiasthmatic drugs, as they possess both immunomodulatory and bronchodilatory properties. 相似文献44.
Elena Garcia‐Martin Luis E. Pablo Raquel Herrero Jose R. Ara Jesus Martin Jose M. Larrosa Vicente Polo Julian Garcia‐Feijoo Javier Fernandez 《Acta ophthalmologica. Supplement》2013,91(8):e628-e634
Purpose: To compare axonal loss in ganglion cells detected with spectral‐domain optical coherence tomography (OCT) in eyes of patients with multiple sclerosis (MS) versus healthy control subjects using an artificial neural network (ANN). To analyse the capability of the ANN technique to improve the detection of retinal nerve fibre layer (RNFL) damage in patients with multiple sclerosis. Methods: Patients with multiple sclerosis (n = 106) and age‐matched healthy subjects (n = 115) were enrolled. The Spectralis OCT system was used to obtain the circumpapillary RNFL thickness in both eyes. The 768 RNFL thickness measurements provided by the Spectralis OCT were performed to obtain thickness measurements from 24 uniformly divided locations around the peripapillary RNFL. The performance of the ANN technique for identifying RNFL loss in patients with multiple sclerosis was evaluated. Receiver‐operating characteristic (ROC) curves were used to display the ability of the test to discriminate between MS and healthy eyes in our population. ROC curves obtained using ANN and parameters provided by OCT (mean and 6 sector thicknesses) were compared. Results: The capability of the ANN technique to detect RNFL loss in patients with multiple sclerosis compared with healthy subjects was good. The area under the ROC curve was 0.945. Compared with the OCT‐provided parameters, the ANN had the largest area under the ROC curve. Conclusions: Measurements of RNFL thickness obtained with Spectralis OCT have a good ability to differentiate between healthy and individuals with multiple sclerosis. Based on the area under the ROC curve, the ANN performed better than any single OCT parameter. 相似文献
45.
Grance SR Teixeira MA Leite RS Guimarães EB de Siqueira JM de Oliveira Filiu WF de Souza Vasconcelos SB do Carmo Vieira M 《Journal of ethnopharmacology》2008,117(1):28-33
AIM OF THE STUDY: This investigation evaluated the effect of a hydroethanolic extract of Baccharis trimera on pregnant Wistar rats, once the plant is well-known consumed in pregnancy and little is known on its potentially toxic effects on pregnant women. MATERIAL AND METHODS: Thirty-five female rats were distributed into three groups. Those in treatments 1 and 2 were given 8.4 mg/kg of the extract orally from gestational day (GD) 1 to 19 and from GD 6 to 15, respectively, whereas those in the control group received distilled water orally from GD 1 to 19. Body weights were recorded on GD 1, 6, 15, and 20. On GD 20 animals were anesthetized, blood samples were collected and maternal livers, kidneys, and spleens were weighed and processed for histological studies. RESULTS: No clinical signs of maternal toxicity and no changes in hematological parameters were observed. Urea levels and kidney weights differed significantly between animals receiving treatment 1 and controls. Histopathological alterations were found in kidneys and livers in both treatment groups. CONCLUSIONS: The hydroethanolic extract of Baccharis trimera administered to pregnant rats at 8.4 mg/kg was toxic to maternal kidney and liver cells, although such alterations are reversible once administration is discontinued. 相似文献
46.
47.
Carnot Ntafam Adam T. Miller Bryce D. Beutler Judith Bamporiki Ara B. Sahakian Phillip M. Cheng 《Radiology Case Reports》2022,17(10):3504
Schwannomas are common peripheral nerve sheath tumors that typically occur on the head, neck, trunk, or extremities. Intra-abdominal schwannomas, however, are rare. We describe a young woman who presented for imaging evaluation of suspected nephrolithiasis and was incidentally found to have a schwannoma centered within the pancreatic parenchyma. In addition, we detail the clinical, imaging, and histopathologic features of pancreatic schwannoma and summarize diagnosis and management of this rare clinical entity. 相似文献
48.
Daltro C Gregorio PB Alves E Abreu M Bomfim D Chicourel MH Araújo L Cotrim HP 《Obesity surgery》2007,17(6):809-814
Background Obesity is the most important risk factor for obstructive sleep apnea. It is estimated that 70% of sleep apnea patients are
obese. In the morbidly obese, the prevalence may reach 80% in men and 50% in women. The aim of this study was to determine
the prevalence and severity of sleep apnea in a group of morbidly obese patients, leading to bariatric surgery.
Methods In a cross-sectional study developed in Bahia, northeastern Brazil. 108 patients (78 women and 30 men) from the Obesity Treatment
and Surgery Center - “Núcleo de Tratamento e Cirurgia da Obesidade” underwent standard polysomnography. Patients with an apnea-hypopnea
index (AHI) ≥ 5 events/hour were considered apneic.
Results Mean ± SD for age and BMI were 37.1 ± 10.2 years and 45.2 ± 5.4 kg/m2, respectively. The calculated AHI ranged widely from
2.5 to 128.9 events/hour. Sleep apnea was detected in 93.6% of the sample, wherein 35.2% had mild, 30.6% moderate and 27.8%
severe apnea. Oxyhemoglobin desaturation was directly related to the AHI and was more severe in men.
Conclusion There was a high frequency of sleep apnea in this group of morbidly obese patients, for whom it was very important to request
polysomnography, thus enabling therapeutic management and prognostication. 相似文献
49.
Colorectal endoscopic submucosal dissection: Systematic review of mid‐term clinical outcomes 下载免费PDF全文
Nisha Patel Kinesh Patel Hutan Ashrafian Thanos Athanasiou Ara Darzi Julian Teare 《Digestive endoscopy》2016,28(4):405-416
With a drive towards minimally invasive surgery, endoscopic submucosal dissection (ESD) is now gaining popularity. In a number of East Asian countries, ESD is now the treatment of choice for early non‐metastatic gastric cancer, but the outcomes of ESD for colorectal lesions are unclear. The present review summarizes the mid‐term outcomes of colorectal ESD including complication and recurrence rates. A systematic literature search was done in May 2014, identifying 20 publications reporting the outcomes of colorectal ESD which were included in this review. En‐bloc resection rates, complete (R0) resection rates, endoscopic clearance rates, complication and recurrences rates were analyzed. Statistical pooling was done to calculate weighted means using random effects modeling. Twenty studies reporting the outcomes of 3060 colorectal ESD procedures were reported. Overall weighted en‐bloc resection rate was 89% (95% CI: 83–94%), R0 resection rate 76% (95% CI: 69–83%), endoscopic clearance rate 94% (95% CI: 90–97%) and recurrence rate 1% (95% CI: 0.5–2%). Studies that followed up patients for over 1 year were found to have an en‐bloc resection rate of 91% (95% CI: 86–96%), R0 resection rate of 81% (95% CI: 75–88%), endoscopic clearance rate 93% (95% CI: 90–97%) and recurrence rate of 0.8% (95% CI: 0.4–1%). Colorectal ESD can be carried out effectively and safely with a 1% recurrence rate. Further studies with longer follow‐up periods are required to determine whether colorectal ESD is a viable alternative to conventional surgical therapy. 相似文献
50.
Xiaoyi Jin Tomoyuki Koike Takashi Chiba Yutaka Kondo Nobuyuki Ara Kaname Uno Naoki Asano Katsunori Iijima Akira Imatani Mika Watanabe Akio Shirane Tooru Shimosegawa 《Digestive endoscopy》2013,25(5):547-549
In the present paper, we report a case of rare collagenous gastritis. The patient was a 25‐year‐old man who had experienced nausea, abdominal distention and epigastralgia since 2005. Esophagogastroduodenoscopy (EGD) carried out at initial examination by the patient's local doctor revealed an extensively discolored depression from the upper gastric body to the lower gastric body, mainly including the greater curvature, accompanied by residual mucosa with multiple islands and nodularity with a cobblestone appearance. Initial biopsies sampled from the nodules and accompanying atrophic mucosa were diagnosed as chronic gastritis. In August, 2011, the patient was referred to Tohoku University Hospital for observation and treatment. EGD at our hospital showed the same findings as those by the patient's local doctor. Pathological findings included a membranous collagen band in the superficial layer area of the gastric mucosa, which led to a diagnosis of collagenous gastritis. Collagenous gastritis is an extremely rare disease, but it is important to recognize its characteristic endoscopic findings to make a diagnosis. 相似文献