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A 47-year-old woman with adenocarcinoma of the right breast had bone scintigraphy with Tc-99m MDP. Bone imaging did not show any metastases. However, a large area of increased tracer uptake was seen extending from the abdomen to the pelvis. Abdominal ultrasound revealed a large solid and heterogeneous mass, measuring 18 x 11 x 14.3 cm, that originated in an empty uterus. A biopsy of the surgical specimen showed a leiomyoma of the uterus.  相似文献   
34.
An alcohol-free grape-skin extract (GSE) obtained from skins of Vitis labrusca has significant anti-hypertensive, antioxidant and vasodilator effects. According to our previous results, the vasodilator effect of GSE in the isolated mesenteric vascular bed (MVB) of the rat is dependent on endothelium and partially dependent on nitric oxide (NO). In the MVB of the rat pre-contracted with norepinephrine (NE), bolus injections of GSE induced a long-lasting dose-dependent vasodilation that is significantly reduced after the treatment with 1H-[1,2,3] oxadiazolo [4,4-a] quinoxalin-1-one (ODQ). Additionally, in vessels pre-contracted with norepinephrine and depolarized with KCl (25 mM) or treated with Ca(2+)-dependent K(+)-channel blockers charybdotoxin (ChTx) plus apamin, the vasodilator effect of GSE was significantly reduced and almost abolished by ChTx plus apamin plus L-NAME. However, the vasodilator effect of GSE was unaffected by D-Arg[Hyp(3),Thi(5),D-Tic(7),Oic(8)]bradykinin (HOE-140), atropine, yohimbine, pyrilamine and 4-aminopyridine (4-AP). The vasoconstriction response elicited by bolus injection of KCl was not affected by GSE, whereas the vasoconstrictor response induced by NE was dose-dependently and completed inhibited by GSE in the presence but not in the absence of endothelium. However, NE-induced vasoconstriction in calcium-free condition or without endothelium was not reduced by GSE. The present results demonstrate that GSE induces a vasodilator effect in the rat MVB, which is dependent on NO in combination with endothelium-derived hyperpolarizing factor (EDHF). Additionally, our results indicated that extracellular Ca(2+) has an important role on the endothelium-dependent vasodilator effect induced by GSE.  相似文献   
35.
IntroductionWe aimed to compare the rate of postoperative infection and drug-resistant organism (DRO) before and during the COVID-19 pandemic in urology departments.MethodsA retrospective cohort study was carried out. Data from all elective surgical procedures carried out in two urology departments between April and June 2018 and the homologous period in 2020 were collected. Main outcomes were the number of postoperative infections during the pandemic and the number of DROs. Sample size was calculated based on a 50% relative reduction of infections during the pandemic. Variables were compared by Chi-squared test, and multivariable logistic regression was used to estimate predictors.ResultsA total of 698 patients undergoing elective surgery were included. The postoperative infection rate during the pre-pandemic period was of 14.1% compared to 12.1% during the pandemic (p=0.494). DROs were lower during the pandemic (92.3% vs. 52.4%, p=0.002). The pandemic period was the main predictor for reduced multidrug-resistant isolates, with an odds ratio of 0.10 (p=0.010, 95% confidence interval 0.016–0.57).ConclusionsPostoperative infection rates were not significantly reduced during the COVID-19 pandemic, despite the adoption of enhanced infection preventive measures. There was, however, a decrease in the rate of DROs during this period, suggesting a secondary benefit to enhanced infection prevention practices adopted during the COVID-19 era.  相似文献   
36.
Viral infections have haunted humankind since times immemorial.Overpopulation,globalization,and extensive deforestation have created an ideal environment for a ...  相似文献   
37.
Several plant species are used in Brazil to treat inflammatory diseases and associated conditions. TNF‐α plays a pivotal role on inflammation, and several plant extracts have been assayed against this target, both in vitro and in vivo. The effect of 11 Brazilian medicinal plants on TNF‐α release by LPS‐activated THP‐1 cells was evaluated. The plant materials were percolated with different solvents to afford 15 crude extracts, whose effect on TNF‐α release was determined by ELISA. Among the evaluated extracts, only Jacaranda caroba (Bignoniaceae) presented strong toxicity to THP‐1 cells. Considering the 14 non‐toxic extracts, TNF‐α release was significantly reduced by seven of them (inhibition > 80%), originating from six plants, namely Cuphea carthagenensis (Lythraceae), Echinodorus grandiflorus (Alismataceae), Mansoa hirsuta (Bignoniaceae), Ouratea semiserrata (Ochnaceae), Ouratea spectabilis and Remijia ferruginea (Rubiaceae). The ethanol extract from O. semiserrata leaves was fractionated over Sephadex LH‐20 and RP‐HPLC to give three compounds previously reported for the species, along with agathisflavone and epicatechin, here described for the first time in the plant. Epicatechin and lanceoloside A elicited significant inhibition of TNF‐α release, indicating that they may account for the effect produced by O. semiserrata crude extract. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
38.

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   
39.
In this work, a new solid phase spectrophotometric method in association with flow injection analysis for Vitamin B6 (pyridoxine) determination has been developed with direct measurement of light-absorption in C18 material. In the developed method, successive passage of the complex, previously formed in the flowing stream, and eluent through the flow cell and continuous monitoring of the process provided the analytical information needed to determine pyridoxine. Pharmaceutical samples containing Vitamin B6 were previously dissolved in 0.1 mol l(-1) phosphate buffer solution (pH 7.5) and a sample volume of 235 microl was injected directly into carrier stream consisting of a mixture of methanol and 0.1 mol l(-1) phosphate buffer solution adjusted to pH 7.0 (1+1, v/v). The blue indophenol dye produced from the reaction between pyridoxine and N,N-diethyl-p-phenylenediamine after oxidation by potassium hexacyanoferrate(III) was quantitatively retained on C18 support and the spectrophotometric detection was performed simultaneously at 633 nm. The retained complex was quickly eluted from C18 material with the eluent stream consisting of a mixture of methanol and 0.01 mol l(-1) HCl (6+4, v/v). The results showed that the proposed method is simple, rapid and the analytical response is linear in the concentration range of 0.5-10 and 0.2-4 mg l(-1) using 235 and 860 microl of sample, respectively. The limits of detection are 0.15 and 0.060 mg l(-1) and the R.S.D. are 3.6% (at 2 mg l(-1) level) and 4.0% (at 1 mg l(-1) level) using sample volume of 235 and 860 microl, respectively. The system presented an analytical throughput of 15 determinations per hour when a sample volume of 235 microl was utilized. The procedure was successfully applied to the determination of Vitamin B6 in pharmaceutical formulations containing vitamins of B group and others active principles such as Vitamin C and minerals.  相似文献   
40.
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   
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