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991.
《Expert Review of Gastroenterology & Hepatology》2013,7(12):1495-1500
Early diagnosis and adequate empirical antibiotic treatment of bacterial infections in advanced cirrhosis is essential to improve outcomes given the high risk of developing severe sepsis, multiple organ failure and death. β-lactams and quinolones are nowadays frequently ineffective in nosocomial and healthcare associated infections, due to the increasing prevalence of multidrug resistant (MDR) bacteria reported across different geographical areas. Recent antibiotic exposure also increases the risk of developing MDR bacterial infections. Initial antibiotic strategies should therefore be tailored according to the presence or absence of risk factors of MDR bacteria and to the severity of infection and should consider the local epidemiology. Empirical treatment in the population at high risk of MDR bacterial infections requires the use of broad-spectrum antibiotics (carbapenems or tigecycline) and of drugs active against specific resistant bacteria (glycopeptides, linezolid, daptomycin, amikacin, colistin). Early de-escalation policies are recommended to prevent the spread of MDR bacteria in cirrhosis. 相似文献
992.
Lingling Zhang Wenjun Ding Huixing Sun Qiong Zhou JingQun Huang Xuefen Li Yonghong Xie Jianzong Chen 《Food and chemical toxicology》2012
Oxidative stress plays an important role in the pathogenesis of Parkinson’s disease (PD). Salidroside (SAL), a phenylpropanoid glycoside isolated from Rhodiola rosea L., can exert potent antioxidant properties. In this study, we investigated the protective effects, and the possible mechanism of action, of SAL against 1-methyl-4-phenylpyridinium (MPP+)-induced cell damage in rat adrenal pheochromocytoma PC12 cells. Pretreatment of PC12 cells with SAL significantly reduced the ability of MPP+ to induce apoptosis in a dose and time-dependent manner. SAL significantly and dose-dependently inhibited MPP+-induced chromatin condensation and MPP+-induced release of lactate dehydrogenase by PC12 cells. SAL enhanced Akt phosphorylation in PC12 cells, and the protective effects of SAL against MPP+-induced apoptosis were abolished by LY294002, a specific inhibitor of phosphatidylinositol 3-kinase (PI3K) phosphorylation. These findings suggest that SAL prevents MPP+-induced apoptosis in PC12 cells, at least in part through activation of the PI3K/Akt pathway. 相似文献
993.
Immunization of pregnant women against influenza is a promising strategy to protect the mother, fetus, and young infant from influenza-related diseases. The burden of influenza during pregnancy, the vaccine immunogenicity during this period, and the robust influenza vaccine safety database underpin recommendations that all pregnant women receive the vaccine to decrease complications of influenza disease during their pregnancies. Recent data also support maternal immunization for the additional purpose of preventing disease in the infant during the first six months of life. 相似文献
994.
目的探讨阴茎背神经离断术联合高选择性α1受体阻断药治疗早泄的疗效。方法对89例早泄患者随机分为3组:单纯药物治疗组、单纯阴茎背神经离断组、联合治疗组,每组给予相应治疗,观察阴道内射精潜伏期的变化。结果联合治疗组阴道内射精潜伏期(160.4±57.7 s)较单纯药物α1受体阻断药治疗组(64.3±23.2 s)和单纯阴茎背神经离断组(106.5±41.4 s)明显延长(P<0.01)。结论阴茎背神经离断术联合高选择性α1受体阻断药治疗早泄效果明显。 相似文献
995.
Xiaolei Ze Fanny Le Mougen Sylvia H. Duncan Petra Louis Harry J. Flint 《Gut microbes》2013,4(3):236-240
The microbial communities found in the mammalian large intestine and rumen efficiently degrade many recalcitrant substrates that are resistant to the host’s digestive enzymes. These communities are known from molecular profiling to be highly diverse at the species and strain level, but it may be that only certain specialized organisms (“keystone species”) have the ability to initiate degradation of such substrates, thus releasing energy on which the rest of the community depends. We have recently reported that Ruminococcus bromii has a superior ability to degrade certain forms of particulate resistant starch (RS) when compared with other highly abundant species of amylolytic bacteria found in the human colon and have presented evidence that this bacterium provides an example of a keystone species within the microbial community with respect to RS fermentation. The concept of keystone species can be equally relevant to other activities, e.g., those involved in stabilizing the community. 相似文献
996.
Evandro Luís Niero Bianca Rocha-Sales Camila Lauand Beatriz Araujo Cortez Marcelo Medina de Souza Paula Rezende-Teixeira Marcel Shiniti Urabayashi Adam Arai Martens Jorge Henrique Neves Gláucia Maria Machado-Santelli 《Journal of experimental & clinical cancer research : CR》2014,33(1):37
Some cancers like melanoma and pancreatic and ovarian cancers, for example, commonly display resistance to chemotherapy, and this is the major obstacle to a better prognosis of patients. Frequently, literature presents studies in monolayer cell cultures, 3D cell cultures or in vivo studies, but rarely the same work compares results of drug resistance in different models. Several of these works are presented in this review and show that usually cells in 3D culture are more resistant to drugs than monolayer cultured cells due to different mechanisms. Searching for new strategies to sensitize different tumors to chemotherapy, many methods have been studied to understand the mechanisms whereby cancer cells acquire drug resistance. These methods have been strongly advanced along the years and therapies using different drugs have been increasingly proposed to induce cell death in resistant cells of different cancers. Recently, cancer stem cells (CSCs) have been extensively studied because they would be the only cells capable of sustaining tumorigenesis. It is believed that the resistance of CSCs to currently used chemotherapeutics is a major contributing factor in cancer recurrence and later metastasis development. This review aims to appraise the experimental progress in the study of acquired drug resistance of cancer cells in different models as well as to understand the role of CSCs as the major contributing factor in cancer recurrence and metastasis development, describing how CSCs can be identified and isolated. 相似文献
997.
《European journal of medical genetics》2022,65(1):104382
Andersen-Tawil syndrome (ATS) and Noonan syndrome (NS) are both autosomal dominantly inherited disorders that share anomalies in the same body systems, i.e. cardiovascular system, skeleton, growth, and face morphology. Here we report a patient meeting clinical diagnostic criteria for NS in whom no variant in one of the genes known to cause NS was found and a pathogenic variant in KCNJ2 (c.653G > C, p.(Arg218Pro)) was demonstrated. Because of manifestations typical for NS and previously not described in ATS (broad neck, low hairline and pectus excavatum), this may indicate there is a phenotypical overlap between ATS and NS, although we cannot exclude that the patient has an additional, hitherto undetected variant in another gene that explains the NS features. Further studies into a functional relation between KCNJ2 and the RAS/MAPK pathway are needed to determine this further. 相似文献
998.
999.
《Pharmaceutical development and technology》2013,18(4):897-905
There has been growing interest in orally disintegrating tablets (ODTs) during the last decade due to their better patient acceptance and compliance. Further, drug dissolution and absorption may be significantly improved. This work describes the preparation of fast and pH-dependent release ODTs for domperidone by direct compression using crospovidone as superdisintegrant. Solid dispersions of domperidone and Eudragit L100-55, at different weight ratios, were prepared and characterized by DSC, TGA, X-ray diffraction, and FTIR, which indicated the presence of drug–polymer interaction. Disintegration time, friability, and hardness of ODTs were evaluated. In vitro drug release in 0.1N HCl and in phosphate buffer (pH 5.8 and 6.8) was investigated. All domperidone ODTs had fast disintegration times (6 KP) and acceptable friability (<1%). Drug release from fast release ODTs was highly improved; reaching 97% after 10?min in 0.1N HCl, compared to the dissolution of the free drug. Drug release from solid dispersions was pH dependent; showing higher release rates at pH 6.8 than at lower pH values. The controlled-release ODT resulted in 47% drug release in 0.1N HCl, with the rest of drug released at pH 6.8. Domperidone ODTs were considered suitable for ODT formulation. 相似文献
1000.
《Clinical and experimental hypertension (New York, N.Y. : 1993)》2013,35(7-8):753-767
Astrocytes react to all noxae which damage neurons. Their reactions include degeneration, hypertrophy, hyperplasia and fibre formation. Growth factors inducing proliferation and differentiation of both neurons and astrocytes in culture play a pivotal role in the dynamic flow of signaling molecules between neurons and astroglia. Estrogens as well influence astroglia and are neuroprotectants. This study has investigated the interactions between growth factors and estrogens on DNA labeling and cytoskeletal protein [glial fibrillary acidic protein (GFAP) and vimentin] expression in 22 DIV astrocyte cultures treated for 24 or 36?h under different experimental conditions.Contemporary addition of 17-β-estradiol (E2) with two or three growth factors for 24?h, significantly stimulated methyl-[3H]thymidine incorporation into DNA from 22 days in vitro (DIV) astrocyte cultures.This effect reached a peak when E2 was co-added with epidermal growth factor (EGF), basic fibroblast growth factor (bFGF) and insulin. In astrocyte cultures treated for 36?h with E2 and EGF+insulin or bFGF+insulin added in the last 12?h, DNA labeling was remarkably increased. The parallel cyclin D1 expression positively correlated with ERK2 activation. Western blot analysis for cytoskeletal proteins showed also changes of both GFAP and vimentin expression. The above data suggest the occurrence of a scheduled interaction between “competence” or “progression” growth factors and estrogens on DNA labeling and cytoskeletal protein expression during astroglial cell proliferation and differentiation in culture. A better understanding of the mechanisms of these interactions may contribute to develop strategies for controlling astroglial reaction in cerebrovascular disease including stroke and hypertensive brain damage. 相似文献