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排序方式: 共有1177条查询结果,搜索用时 187 毫秒
61.
Katja M?enp?? Ville Ell? Jari Mauno Minna Kellom?ki Riitta Suuronen Timo Ylikomi Susanna Miettinen 《Journal of the Royal Society Interface》2010,7(42):177-188
There is currently no suitable replacement for damaged temporomandibular joint (TMJ) discs after discectomy. In the present study, we fabricated bilayer biodegradable polylactide (PLA) discs comprising a non-woven mat of poly(L/D)lactide (P(L/D)LA) 96/4 and a P(L/DL)LA 70/30 membrane plate. The PLA disc was examined in combination with adipose stem cells (ASCs) for tissue engineering of the fibrocartilaginous TMJ disc in vitro. ASCs were cultured in parallel in control and chondrogenic medium for a maximum of six weeks. Relative expression of the genes, aggrecan, type I collagen and type II collagen present in the TMJ disc extracellular matrix increased in the ASC-seeded PLA discs in the chondrogenic medium. The hypertrophic marker, type X collagen, was moderately induced. Alcian blue staining showed accumulation of sulphated glycosaminoglycans. ASC differentiation in the PLA discs was close to that observed in pellet cultures. Comparison of the mRNA levels revealed that the degree of ASC differentiation was lower than that in TMJ disc-derived cells and tissue. The pellet format supported the phenotype of the TMJ disc-derived cells under chondrogenic conditions and also enhanced their hyalinization potential, which is considered part of the TMJ disc degeneration process. Accordingly, the combination of ASCs and PLA discs has potential for the development of a tissue-engineered TMJ disc replacement. 相似文献
62.
Jari Lyytimäki 《Water and Environment Journal》2012,26(3):405-414
The mass media shape the public and policy agenda by giving prominence to certain ecosystem changes and risks, as well as by framing some policy measures as the preferred ones. Based on longitudinal analysis of the leading Finnish newspaper, this study considers the media coverage of eutrophication. The results show an increase of reporting in the late 1990s as a result of intertwined ecological and social factors – i.e. intense algal occurrences and establishment of a national communication system. The news coverage has highlighted the harmful algal blooms and health risks of algal toxins and has framed short‐term weather conditions as the key factor regulating algal occurrences. This creates a challenge for environmental management aimed at reduction in the nutrient discharges that influence the state of the environment in the long term. 相似文献
63.
Heikki Käsnänen Mikko J. Myllymäki Anna Minkkilä Antti O. Kataja Susanna M. Saario Dr. Tapio Nevalainen Dr. Ari M. P. Koskinen Prof. Dr. Antti Poso Prof. Dr. 《ChemMedChem》2010,5(2):213-231
Carbamates are a well‐established class of fatty acid amide hydrolase (FAAH) inhibitors. Here we describe the synthesis of meta‐substituted phenolic N‐alkyl/aryl carbamates and their in vitro FAAH inhibitory activities. The most potent compound, 3‐(oxazol‐2yl)phenyl cyclohexylcarbamate ( 2 a ), inhibited FAAH with a sub‐nanomolar IC50 value (IC50=0.74 nM ). Additionally, we developed and validated three‐dimensional quantitative structure–activity relationships (QSAR) models of FAAH inhibition combining the newly disclosed carbamates with our previously published inhibitors to give a total set of 99 compounds. Prior to 3D‐QSAR modeling, the degree of correlation between FAAH inhibition and in silico reactivity was also established. Both 3D‐QSAR methods used, CoMSIA and GRID/GOLPE, produced statistically significant models with coefficient of correlation for external prediction (R2PRED) values of 0.732 and 0.760, respectively. These models could be of high value in further FAAH inhibitor design. 相似文献
64.
Pihlajamäki H Mäkelä EA Ashammakhi N Viljanen J Pätiälä H Rokkanen P Pohjonen T Törmälä P Joukainen A 《Journal of materials science. Materials in medicine》2002,13(4):389-395
Drawn self-reinforced polyglycolide (SR-PGA) rods, Ø 2 mm and 26 mm long, were implanted in the dorsal subcutaneus tissue of 16 rats. Osteotomies of the distal femur were fixed with SR-PGA rods (2 mm by 15 mm) in another 38 rats. The follow-up times varied from one week to one year. After sacrifice, three-point bending and shear tests were performed for subcutaneously placed rods. Radiological, histological, histomorphometrical, microradiographic, and oxytetracycline-fluorescence studies of osteotomized and intact control femora were also performed. At three weeks the flexural strength of the rods was 50% of the initial value, and the flexural modulus was 46% of the initial value. Five osteotomy specimens had to be excluded due to dislocation or non-union. One of the 33 evaluated osteotomy specimens showed signs of postoperative infection. Thirty-two osteotomies healed uneventfully. No gross signs of inflammatory or foreign-body reaction were observed. The amount of osteoid surface and active osteoid formation surface reached their highest value in the histomorphometrical analysis at 24 weeks. The present investigation demonstrated that the mechanical strength and fixation properties of the drawn SR-PGA rods are suitable for fixation of cancellous bone osteotomies in rats. The present article is the first report on the successful application of drawn SR-PGA rods for fixation of cancellous bone osteotomies. 相似文献
65.
Repokari Leena; Punam?ki Raija-Leena; Poikkeus Piia; Tiitinen Aila; Vilska Sirpa; Unkila-Kallio Leila; Sinkkonen Jari; Almqvist Frederick; Tulppala Maija 《Canadian Metallurgical Quarterly》2006,20(4):670
In this prospective controlled study, the authors examined (a) parenting experiences among couples with successful assisted reproduction treatment (ART; n = 367) and fertile spontaneously conceiving controls (n = 371) and (b) the impact of ante- and perinatal factors and child characteristics on parenting experiences. The results show that positive mothering experiences increased more during the 1st year of parenting and were generally higher among ART mothers than control mothers. No differences were found between ART fathers and controls in their fathering experience. Unpleasant birth experiences, low birth weight, and difficulty soothing the child were associated with high levels of parental stress in the control group, but this was not so among the ART parents. Psychosocial interventions in maternal care should take into account the various meanings that couples give to the history of infertility and conception and ante- and perinatal experiences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
This paper describes a method for detecting oxygen consumption of adherent cell cultures. The sensing is based on oxygen-dependent quenching of the phosphorescence of a Pt-porphyrin complex immobilized on microcarrier beads, which are used as the cell culture substrate. Bead injection, a recent variant of the flow injection technique, is used to pack an aliquot of the beads into a small sensing layer that can be easily and rapidly renewed. The technique is tested on a model system of Chinese Hamster Ovary M1 cells grown on Cytodex-3 microcarrier beads. Cellular respiration is monitored through O2 consumption measured across a period of 3 min. The method is validated by detecting the impairment of aerobic metabolism caused by 1.5 mM amobarbital. Further, it is shown to have enough precision to distinguish even more subtle changes, such as the increase in oxygen consumption caused by stimulation of the muscarinic m1 receptor with 100 microM carbachol. 相似文献
67.
An aerobic membrane bioreactor (MBR) at complete biomass retention was studied over a period of time under starvation conditions. Kinetic parameters were determined in a no‐feed batch test. The decay rate of activated sludge, kd = 0.05 d–1, was determined by tracking the decrease of MLSS. The ratio of MLVSS/MLSS was in the range 0.76–0.85. The pH values were between 7.02 and 8.23. As a function of different initial concentrations of MLSS, specific nitrification rates qN, decreased from 4.23 to 0.02 mg‐N/(g MLVSS d) and specific biodegradation rates qb increased from 0.23 to 1.90 mg‐COD/(g MLVSS d). From experimental data the kinetic constants for respiration, which followed Monod kinetics, were determined as qO2max = 9.8 mg‐O2/(g MLVSS h), Kx = 2.9 g/dm3. Additionally, a linear correlation between MLSS and mean floc size was found to exist during the biodegradation process. 相似文献
68.
69.
B Kruslin S Juki? Z Delija-Prese?ki G Simi? M Kos T Tkalcevi? 《Canadian Metallurgical Quarterly》1996,118(7-8):152-154
We have analyzed all available data including birth certificates, maternity records, pediatric records, and pathology reports of spontaneous and induced abortions and newborn deaths to determine the frequency of congenital anomalies of the central nervous system. We found 76 infants (34 males, 39 females and 3 of undetermined sex) with CNS anomalies during the 1990-93 period. In the same period there were 23,425 births. The frequency of CNS anomalies in this period was 32,4/10,000 births. These results are at variance with conclusions of previously published and incomprehensive studies in Croatia. Therefore, a systematic follow-up of the autopsy findings of induced and spontaneous abortions and newborn deaths in the epidemiology of CNS anomalies is clearly needed. 相似文献
70.
KM Mattila C Forsell T Pirttil? JO Rinne T Lehtim?ki M R?ytt? L Lilius A Eerola PH St George-Hyslop H Frey L Lannfelt 《Canadian Metallurgical Quarterly》1998,44(6):965-967
In early-onset familial Alzheimer's disease (AD) pathogenic mutations have been found in the amyloid precursor protein (APP) gene and in the presenilin (PS)-1 and PS-2 genes. We screened for mutations in these genes in 20 patients with familial AD from the Finnish population. In addition, we sampled 41 sporadic AD patients and 59 controls to test for mutations identified in our familial AD cases. We detected an A-to-G transition in the PS-1 gene, resulting in a glutamic acid (Glu)-to-glycine (Gly) substitution at codon 318 in 2 familial and 2 sporadic AD patients. The Glu318Gly mutation has previously been reported to cause AD. We also found the Glu318Gly mutation in 4 healthy aged controls (range, 74-87 years). We thus conclude that the mutation is most likely a rare polymorphism not related to AD. 相似文献