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排序方式: 共有832条查询结果,搜索用时 15 毫秒
101.
102.
JL Mokrosz B Duszyńska S Charakchieva-Minol AJ Bojarski MJ Mokrosz RL Wydra L Janda L Strekowski 《European journal of medicinal chemistry》1996,31(12):973-980
New N-methylpiperazino-substituted quinazolines 8 and 9, phthalazine 13, and quinoline 19 have been synthesized. The receptor binding profiles (α1, 5-HT1A, 5-HT2A) of these compounds and their analogs (7–22) have been determined. It has been demonstrated that orientation of a local dipole moment of the heteroaromatic ring system affects both the α1 and 5-HT2A affinity of the investigated class of ligands. Distortion of the coplanar unfused heteroaromatic ring system results in a decreased 5-HT2A affinity. 4-(4-Methylpiperazino)-2-(2-thienyl)quinoline 18 is the most active and selective α1 ligand (Ki = 4.9 nM) with a much lower affinity for 5-HT1A (Ki = 3420 nM) and 5-HT2A (Ki = 211 nM) receptors. 相似文献
103.
Biological evaluation of intervertebral disc cells in different formulations of gellan gum‐based hydrogels 下载免费PDF全文
G Khang SK Lee HN Kim J Silva‐Correia ME Gomes CAA Viegas IR Dias JM Oliveira RL Reis 《Journal of tissue engineering and regenerative medicine》2015,9(3):265-275
Gellan gum (GG)‐based hydrogels are advantageous in tissue engineering not only due to their ability to retain large quantities of water and provide a similar environment to that of natural extracellular matrix (ECM), but also because they can gelify in situ in seconds. Their mechanical properties can be fine‐tuned to mimic natural tissues such as the nucleus pulposus (NP). This study produced different formulations of GG hydrogels by mixing varying amounts of methacrylated (GG‐MA) and high‐acyl gellan gums (HA‐GG) for applications as acellular and cellular NP substitutes. The hydrogels were physicochemically characterized by dynamic mechanical analysis. Degradation and swelling abilities were assessed by soaking in a phosphate buffered saline solution for up to 170 h. Results showed that as HA‐GG content increased, the modulus of the hydrogels decreased. Moreover, increases in HA‐GG content induced greater weight loss in the GG‐MA/HA‐GG formulation compared to GG‐MA hydrogel. Potential cytotoxicity of the hydrogel was assessed by culturing rabbit NP cells up to 7 days. An MTS assay was performed by seeding rabbit NP cells onto the surface of 3D hydrogel disc formulations. Viability of rabbit NP cells encapsulated within the different hydrogel formulations was also evaluated by Calcein‐AM and ATP assays. Results showed that tunable GG‐MA/HA‐GG hydrogels were non‐cytotoxic and supported viability of rabbit NP cells. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
104.
105.
Surface shield: device to reduce personnel radiation exposure 总被引:2,自引:0,他引:2
Young AT; Morin RL; Hunter DW; Nelson KL; Cardella JF; Castaneda-Zuniga WR; Amplatz K 《Radiology》1986,159(3):801-803
A simple device is described that can reduce personnel exposure from scatter radiation by up to 75%. The device consists of an oblong piece of shielding (0.75-mm lead equivalent) that is taped to the side of the patient during percutaneous renal stone removal and other interventional procedures. Contrary to other shields and barriers, this does not interfere with access to the patient. Scatter exposure data from phantom studies are presented and the rationale for surface shielding discussed. 相似文献
106.
107.
RA Parker J Himmelfarb N Tolkoff-Rubin P Chandran RL Wingard RM Hakim 《American journal of kidney diseases》1998,32(3):432-443
Despite several decades of clinical experience, the mortality rate for patients with acute renal failure (ARF) requiring dialysis remains high, and the evaluation of the patients prognosis has been difficult. To date, the Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring system has been used more frequently for prediction in studies of ARF than any other scoring system, but has not been prospectively validated in controlled multicenter studies of this entity. In a multicenter, prospective, controlled trial evaluating the use of biocompatible hemodialysis membranes (BCMs) in patients with ARF, we evaluated the extent to which the APACHE II scoring system, based on the physiological variables in the 24 hours before the onset of dialysis and the presence or absence of oliguria, is predictive of outcome. Analysis of survival and recovery of renal function for the 153 patients treated in this study show that APACHE II scores are predictive both of survival and recovery of renal function, whether analyzed separately by type of dialysis membrane used (BCM or bioincompatible [BICM]) or for both groups combined (all P < 0.01). There was no evidence of a significant center effect or interaction of APACHE II score with dialysis membrane in our study. After adjusting for the APACHE II score, there was a positive effect of the BCM on both probability of survival (P < 0.05) and recovery of renal function (P < 0.01). In patients dialyzed with BCMs, oliguria at onset of dialysis had an adverse effect on both survival and recovery of renal function (both P < 0.01). Receiver operator curves (ROCs) using APACHE II score and the use of BCMs in nonoliguric patients yielded a statistically significant improvement versus the use of APACHE II score alone in the area under the curve (AUC) for survival (0.747 to 0.801; P < 0.05) and recovery of renal function (0.712 to 0.775; P < 0.05). We conclude that the use of the APACHE II score determined at the time of initiation of dialysis for patients with ARF is a statistically significant predictor of patient survival and recovery of renal function. The use of the APACHE II score measured at the time of dialysis initiation, especially when modified by the presence or absence of oliguria, should help in predicting outcome when evaluating interventions for patients with ARF. 相似文献
108.
In vitro and in vivo selectin-blocking activities of sulfated lipids and sulfated sialyl compounds 总被引:2,自引:0,他引:2
Mulligan MS; Warner RL; Lowe JB; Smith PL; Suzuki Y; Miyasaka M; Yamaguchi S; Ohta Y; Tsukada Y; Kiso M; Hasegawa A; Ward PA 《International immunology》1998,10(5):569-575
There is accumulating evidence that sulfated lipids, sulfated
oligosaccharides and other sulfated compounds are reactive with selectins
in a manner that interferes with selectin interactions with their natural
ligands. In the report we describe the ability of sulfated lipids
(sulfatides and gangliosides) and multimeric forms of sulfated sialic acid
to block binding of P- and E-selectin-Ig to neutrophils. The in vivo
ability of these compounds to block lung injury in rats following i.v.
infusion of purified cobra venom factor (CVF), which induces injury that is
L- and P-selectin dependent, was also determined as well as effects on
recruitment of neutrophils, as measured by lung myeloperoxidase. There was
a significant correlation between the ability of sulfated lipids and sialyl
compounds to interfere in vitro with P-selectin-Ig binding to neutrophils
and to protect against P-selectin-dependent acute lung injury induced by
CVF. The biological effects of these sulfated compounds were also
associated with diminished accumulation of neutrophils. The protective
effects of these compounds may be linked to their ability to interfere with
P- selectin binding to counter-receptors on neutrophils.
相似文献
109.
Murakami T; Baron RL; Peterson MS; Oliver JH rd; Davis PL; Confer SR; Federle MP 《Radiology》1996,200(1):69
110.