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排序方式: 共有446条查询结果,搜索用时 15 毫秒
51.
C.Z. DONG H. DE ROCQUIGNY E. RMY S. MELLAC M.C. FOURNI-ZALUSKI B.P. ROQUES 《Chemical biology & drug design》1997,50(4):269-278
Specific interactions between the 72-amino acid nucleocapsid protein NCp7 of the human immunodeficiency virus, type 1 and the genomic RNA are essential for virus replication. Studies on the mechanism of action of NCp7 require a direct visualization of its complexes with nucleic acids and the determination of binding affinities. To facilitate these investigations, fluorescent NCp7 derivatives were developed by introduction in the NCp7 sequence of a non-natural amino acid, (S)-β-(9-acridinyl)alanine (Aca) obtained by a chiral synthetic method. Three fluorescent NCp7 derivatives were obtained by introducing this amino acid at different positions. As shown by NMR, the three-dimensional structure of NCp7 is not altered by introduction of Aca. The fluorescent peptides were found to be as potent as their precursors in interacting with nucleic acids and in promoting HIV-1 genomic RNA dimerization. Moreover, because of their fluorescent properties, these NCp7s can be used at submicromolar concentrations to directly visualize and quantify protein-nucleic acid interactions in solution or after gel electrophoresis. This could facilitate the development of new antiviral agents aimed at inhibiting the functions of NCp7 and studies on the intracellular traffic of NCp7 within the preintegration complex. 相似文献
52.
Among 2096 patients treated for cervical cancer between 1985–1995, genital fistulas developed in 38 cases (1.8%). 16 patients
were affected by rectovaginal, 13 patients had rectovesicovaginal and 9 patients had vesicovaginal fistulas. Median age at
time of first presentation of the fistulas was 54.8 years. Fistula size ranged from 0.1 to 2.0 cm in diameter. Faecal or urinary
leakage through the vagina (44.7%), bleeding (31.5%) and local pain (5.3%) were major clinical symptoms. 10 patients had surgery
for the fistula, the remaining patients were managed conservatively.
Accepted: 14 June 1996 相似文献
53.
The paper reports results of an analysis based on face-to-face interviews with two samples of Prague women aged 20-49: (1) a probabilistic sample (h = 718) of the Prague female population; and (2) a sample of 152 inpatients treated for substance dependence/abuse. Of the inpatients, 79% were diagnosed as alcohol dependent only, 15% as both alcohol dependent and drug dependent/abusers, 6% as drug dependent only. With very few exceptions, those with drug problems among the inpatients abused analgesics, hypnotics, or anxiolytics. With data obtained from the general population sample, two-stage hierarchical logistic regression was run with each of the eleven differently defined substance uses as dependent variables. Four demographic variables were entered as predictors into the regression equations in the first stage. From the seven potential risk factors of substance use statistically significant predictors were entered stepwise in stage two. The major result of the study is the specificity of the pattern of predictors related to each of the eleven considered substance uses. It is also found that in the general population the use of a particular substance is generally uncorrelated with the use of other substances. Alcohol use (even heavy alcohol use) has no relation to smoking, to the use of analgesics, hypnotics, anxiolytics-and is connected with a specific pattern of predictors. 相似文献
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55.
C E Day P E Schurr D E Emmert R E TenBrink D Lednicer 《Journal of medicinal chemistry》1975,18(11):1065-1070
A new assay for agents which normalize beta-lipoproteins in cholesterol-cholic acid fed rats is described. Both lowering of serum cholesterol and of serum heparin precipitable lipoproteins (HPL) were measured at the end of the treatment period. Compounds which shifted the ratio of the decrease in favor of HPL are considered hypo-beta-lipoproteinemic. p-(1-Bicyclo[2.2.2]octyloxy)aniline and several of its derivatives proved active in this assay. The synthesis of these compounds is described. 相似文献
56.
Weber B Emmert MY Behr L Schoenauer R Brokopp C Drögemüller C Modregger P Stampanoni M Vats D Rudin M Bürzle W Farine M Mazza E Frauenfelder T Zannettino AC Zünd G Kretschmar O Falk V Hoerstrup SP 《Biomaterials》2012,33(16):4031-4043
Prenatal heart valve interventions aiming at the early and systematic correction of congenital cardiac malformations represent a promising treatment option in maternal-fetal care. However, definite fetal valve replacements require growing implants adaptive to fetal and postnatal development. The presented study investigates the fetal implantation of prenatally engineered living autologous cell-based heart valves. Autologous amniotic fluid cells (AFCs) were isolated from pregnant sheep between 122 and 128 days of gestation via transuterine sonographic sampling. Stented trileaflet heart valves were fabricated from biodegradable PGA-P4HB composite matrices (n = 9) and seeded with AFCs in vitro. Within the same intervention, tissue engineered heart valves (TEHVs) and unseeded controls were implanted orthotopically into the pulmonary position using an in-utero closed-heart hybrid approach. The transapical valve deployments were successful in all animals with acute survival of 77.8% of fetuses. TEHV in-vivo functionality was assessed using echocardiography as well as angiography. Fetuses were harvested up to 1 week after implantation representing a birth-relevant gestational age. TEHVs showed in vivo functionality with intact valvular integrity and absence of thrombus formation. The presented approach may serve as an experimental basis for future human prenatal cardiac interventions using fully biodegradable autologous cell-based living materials. 相似文献
57.
Stöhr F Emmert MY Lachat ML Stocker R Maggiorini M Falk V Wilhelm MJ 《Interactive Cardiovascular and Thoracic Surgery》2011,12(5):676-680
Extracorporeal membrane oxygenation (ECMO) is increasingly applied as rescue-therapy for patients with severe acute respiratory distress syndrome (ARDS). Here, we evaluate the effect of different configuration strategies (venovenous vs. venoarterial vs. veno-venoarterial) on the outcome. From 2006 to 2008, 30 patients received ECMO for severe ARDS. Patients were divided into three groups according to the configuration: veno-venous (vv; n = 11), venoarterial (va; n=8) or veno-venoarterial (vva; n = 11). Data were prospectively collected and endpoint was 30-day mortality. To identify independent risk factors, univariate analysis was performed for clinical parameters, such as age, body mass index, gender, configuration, low-pH, oxygenation index (pO(2)/FiO(2)) and underlying disease. Thirty-day mortality was 53% (n = 16) for all comers: 63% (n = 7) died in the vv-group, 75% (n = 6) in the va-group and 27% (n = 3) in the vva-group. Although univariate analysis could not rule out a significant predictor for the outcome, there was a trend visible to decreased mortality in the vva-group when compared to vv- and va-groups (27% vs. 63% vs. 75%; P = 0.057). ECMO provides a survival benefit in patients when considering a predicted mortality rate of 80% in ARDS. The configuration mode appears to impact the outcome as the veno-venoarterial appears to further improve the survival in this subset of patients. 相似文献
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59.