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41.
Calcium phosphate formation and ion dissolution rates in silica gel-PDLLA composites 总被引:2,自引:0,他引:2
Sol-gel derived silicas are potential biomaterials both for tissue regeneration and drug delivery applications. In this study, both SiO(2) and calcium and phosphate-containing SiO(2) (CaPSiO(2)) are combined with poly-(DL-lactide) to form a composite. The main properties studied are the ion release rates of biologically important ions (soluble SiO(2) and Ca(2+)) and the formation of bone mineral-like calcium phosphate (CaP) on the composite surface. These properties are studied by varying the quality, content and granule size of silica gel in the composite, and porosity of the polymer. The results indicate that release rates of SiO(2) and Ca(2+) depend mostly on the formed CaP layer, but in some extent also on the granule size of silicas and polymer porosity. The formation of the bone mineral-like CaP is suggested to be induced by a thin SiO(-) layer on the composite surface. However, due to absence of active SiO(2) or CaPSiO(2) granules on the outermost surface, the suitable nanoscale dimensions do not contribute the nucleation and growth and an extra source for calcium is needed instead. The result show also that all composites with varying amount of CaPSiO(2) (10-60 wt%) formed bone mineral-like CaP on their surfaces, which provides possibilities to optimise the mechanical properties of composites. 相似文献
42.
43.
Young W Rewa G Coyte PC Jaglal SB Goodman S Bentley-Taylor M Fountas P Gupta A Levinson A O'Connor T;Home Care after a Heart Attack Project Group Partners for Health 《The Canadian journal of cardiology》2003,19(3):231-235
Partners for Health convened an interdisciplinary team to evaluate the quality of care received by cardiac patients. The team detailed the suboptimal postacute care of patients with ischemic heart disease. To solve the quality problems, a cross-sectoral team, using an approach that is in accordance with the American Heart Association's Scientific Statement on Pathways, systematically developed and implemented an integrated community pathway for myocardial infarction patients. The paper contributes to the literature on pathways by presenting the lessons learned from the authors' first-hand experience. The paper concludes with recommendations based on those lessons. 相似文献
44.
Microleakage occurs due to the lack of sealing ability of root sealing materials or adhesive cements used to lute post-core materials. This may cause premature failure of endodontic treatment. The purpose of this study was to evaluate regional bond strengths of four adhesive systems to root canal dentin. Sixteen extracted human single rooted teeth were used. After removing the crowns and the pulp tissues, the root canals were then instrumented and irrigated with or without 5% NaOCl. The root canal dentin walls were then bonded with C&B Metabond, Panavia F, Variolink II, or Rely-X. Microtensile bond strengths to root canal dentin were then measured using an Instron machine. The bond strength data were recorded and expressed in MPa. Statistically significant differences were found among the NaOCl treated and nontreated groups (p < 0.05). C&B Metabond gave the highest bond strength compared with others in the control group (p < 0.05). C&B Metabond also had significantly higher bond strength compared with Variolink II and Panavia F groups when the canals were irrigated with NaOCl (p < 0.05). 相似文献
45.
Treatment of pediatric sinusitis 总被引:5,自引:0,他引:5
The successful management of RS in children relies on careful diagnosis, recognition of causative factors, and judicious yet adequate antibiotic usage. Refractory cases will require surgical therapy, with adenoidectomy as the first-line intervention and ESS reserved for those cases refractory to adenoidectomy. This overall approach will improve quality of life and prevent complications in children with RS. 相似文献
46.
47.
Zaretsky A 《Bipolar disorders》2003,5(Z2):80-87
Pharmacotherapy is the foundation of treatment for bipolar disorder, but research suggests that adjunctive psychosocial interventions that are manualized, reproducible, time-limited, empirically supported, and strategically target a number of critical domains, can efficiently provide additional benefits. Psychoeducation as an adjunct of pharmacotherapy may be beneficial, but questions remain about the utility of this treatment for patients who are already compliant with medication treatment. Family educational interventions have demonstrated encouraging results in relapse prevention, but follow-up data are limited and application to patients who have limited social networks may be problematic. Reports on interpersonal and social rhythm therapy in patients with bipolar disorder are scarce, and what is available shows no differential effect on time to remission or relapse, but a significant impact on subsyndromal symptoms. Follow-up data suggest that patients receiving cognitive behavior therapy have significantly fewer bipolar episodes, shorter episodes, fewer hospitalizations, and less subsyndromal mood symptoms. It is unclear, however, if cognitive behavior therapy is superior to other active psychosocial treatments and whether its mechanism in patients with bipolar disorder is through changing dysfunctional cognitions or simply enhancing early symptom detection. Psychotherapies should be considered early in the course of illness to improve medication compliance and to help patients identify prodromes of relapse in order to take steps for prevention. In addition, some strategies may have a beneficial effect on residual symptoms, particularly symptoms of depression, and thus help move patients toward a more comprehensive functional recovery. 相似文献
48.
Pukkila MJ Kellokoski JK Virtaniemi JA Kumpulainen EJ Johansson RT Halonen PM Kosunen AS Nuutinen J Kosma VM 《The Laryngoscope》2002,112(6):1084-1088
OBJECTIVE: To investigate the expression of inducible nitric oxide synthase (iNOS) in oropharyngeal and hypopharyngeal squamous cell carcinoma (SCC) and its relation to p53 expression, histologic differentiation, clinical data, and prognosis. STUDY DESIGN: A retrospective survey. METHODS: Primary tumors for analyses were obtained from 118 patients diagnosed with SCC of the oropharynx or hypopharynx between 1975 and 1998 in eastern Finland. Immunohistochemical analysis was used to evaluate the expression of iNOS and p53. The expression pattern of iNOS was related to p53 expression, clinical data, and survival. RESULTS: High iNOS score was associated significantly with high nuclear p53 expression index (P = .006) and positive cytoplasmic p53 expression (P = .025). The score for iNOS expression was significantly lower in the largest (T4) tumors (P = .043). No association was seen between iNOS score and N or M class, tumor stage, or histologic differentiation. The score for iNOS expression was not related to overall survival. CONCLUSIONS: The expressions of iNOS and p53 seem to be inter-related in pharyngeal SCC, although the causality remains to be clarified. The expression of iNOS shows no prognostic value in pharyngeal SCC. 相似文献
49.
Jason Brophy Yvonne Yau Peter Cox Kevin Katz Ari Bitnun 《Paediatrics & child health》2007,12(4):319-322
Community-associated methicillin-resistant Staphylococcus aureus is an established pathogen in many centres in the United States, but has yet to establish a firm foothold in Canada. In the present article, the authors report, to their knowledge, Canada’s first fatal paediatric case of invasive disease due to community-associated methicillin-resistant S aureus and review its pathogenesis, epidemiology and treatment. 相似文献
50.
Salla Höyssä Riikka Rontu Pekka Kuukasjärvi Ari Mennander Jari Laurikka Matti Tarkka Kjell Nikus Md. Shaheenul Islam Pekka J. Karhunen Terho Lehtimäki 《Central European Journal of Medicine》2006,1(3):237-249
Lymphotoxin-α (LTA) is a cytokine involved in inflammatory reactions. NFKBIL1 is a regulator of the NF-κB complex. The study investigated
the associations of LTA 804 C>A and NFKBIL1-63 T>A polymorphisms with the use of statin and acetylsalicylic acid (ASA) treatment
in relation to myocardial infarction (MI).
The study population comprised of 600 Finnish individuals who underwent coronary angiography volunteering for the Angiography
and Genes Study. Genotypes were detected by the TaqMan 5′ nuclease assay. We found a interaction between the LTA genotype
(p=0.002) and the NFKBIL1 genotype (p=0.012) and statin treatment in relation to MI. Subjects with the LTA AA or the NFKBIL1
AA genotype were at a 2.77 (95% CI:1.22-6.24) and 2.85 (95% CI:1.22-6.66) times higher risk, respectively, of suffering an
MI when compared to other genotypes among statin non-users. ASA treatment also modulated associations between LTA and NFKBIL1
genotypes and MI (p=0.015 and p=0.028 respectively). The NFKBIL1-A-LTA-A haplotype showed a 61% increase in the risk of MI
compared to the NFKBIL1-T-LTA-C haplotype among statin non-users.
Anti-inflammatory medication modifies the genotype-related risk of MI, suggesting that subjects with LTA and NFKBIL1 AA haplotype
might especially benefit from the treatment. 相似文献