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排序方式: 共有950条查询结果,搜索用时 15 毫秒
41.
A.A.A. Barros A. Alves C. Nunes M.A. Coimbra R.A. Pires R.L. Reis 《Acta biomaterialia》2013,9(11):9086-9097
Ulvan, extracted from the green algae Ulva lactuca, and chitosan, extracted from Loligo forbesis squid-pen, were carboxymethylated, yielding polysaccharides with an average degree of substitution of ~98% (carboxymethyl ulvan, CMU) and ~87% (carboxymethyl chitosan, N,O-CMC). The carboxymethylation was confirmed by Fourier transform infrared spectroscopy and quantified by conductimetric titration and 1H nuclear magnetic resonance. The average molecular weight increased with the carboxymethylation (chitosan, Mn 145→296 kDa and Mw 227→416 kDa; ulvan, Mn 139→261 kDa and Mw 368→640 kDa), indicating successful chemical modifications. Mixtures of the modified polysaccharides were tested in the formulation of polyacrylic acid-free glass-ionomer bone cements. Mechanical and in vitro bioactivity tests indicate that the inclusion of CMU in the cement formulation, i.e. 0.50:0.50 N,O-CMC:CMU, enhances its mechanical performance (compressive strength 52.4 ± 8.0 MPa and modulus 2.3 ± 0.3 GPa), generates non-cytotoxic cements and induces the diffusion of Ca and/or P-based moieties from the surface to the bulk of the cements. 相似文献
42.
The Pacific white shrimp, Litopenaeus vannamei, is the most important shrimp species in volume in world aquaculture. However, in recent decades, outbreaks of diseases, especially viral diseases, have led to significant economic losses, threatening the sustainability of shrimp farming worldwide. In 2004, Brazilian shrimp farming was seriously affected by a new disease caused by the Infectious myonecrosis virus (IMNV). Thus, disease control based on rapid and sensitive pathogen detection methods has become a priority. In this study, a specific quantitation method for IMNV was developed using real-time PCR with SYBR Green chemistry and viral load of the principal target tissues of chronically infected animals was quantified. The quantitative analysis revealed that mean viral load ranged from 5.08 × 108 to 1.33 × 106 copies/μg of total RNA in the hemolymph, 5.096 × 105 to 1.26 × 103 copies/μg in the pleopods, 6.85 × 108 to 3.09 × 104 copies/μg in muscle and 8.15 × 106 to 3.90 × 103 copies/μg in gills. Different viral loads of IMNV were found with greater values in the hemolymph and muscle, followed by the pleopods and gills. 相似文献
43.
The aim of this study was to assess the role of cholinergic transmission in the paraventricular nucleus of the hypothalamus (PVN) and carotid body receptors in mediating a rise in plasma glucose levels in response to hemorrhagic hypotension in rats. Methylatropine (1x10(-9) mol) or 0.15 M NaCl (0.2 microl) was injected into the PVN of Wistar rats weighing 250-300 g bearing a chronic jugular catheter for blood sampling and hemorrhage (1.2 ml/100 g/2 min). Polyethylene cannulae (PE-10) were inserted into the left femoral artery for cardiovascular monitoring. In the other experimental protocol, hemorrhage was performed on rats submitted to bilateral carotid receptor denervation (H-CD). The results show that the hyperglycemic response to hemorrhage was decreased by either methylatropine (H-MA) treatment or bilateral carotid receptor denervation (10.3+/-0.4 mM, control, n=15 vs. 7.7+/-0.2 mM, H-MA, n=12, and 7.6+/-0.3 mM, H-CD, n=5, p<0.01). Furthermore, methylatropine did not affect the recovery of blood pressure after hemorrhage-induced hypotension, suggesting that the metabolic and pressor adjustments have different efferent pathways. Our data demonstrate that cholinergic input from the PVN and carotid receptors (chemo- and/or baroreceptors) might participate in the same neural pathway activated by hemorrhage-induced hypotension that produces hyperglycemia. 相似文献
44.
Hemmerling TM Coimbra C Harvey P Choinière M 《Anesthesia and analgesia》2002,95(6):1675-7, table of contents
IMPLICATIONS: We present the results of a study examining the agreement of bispectral index values obtained using original sensor and subdermal needle electrodes in burn patients. Both types of electrodes can be used interchangeably to monitor depth of sedation. 相似文献
45.
46.
NC de Bruin KA van Velthoven M de Ridder T Stijnen RE Juttmann HJ Degenhart HK Visser 《Archives of disease in childhood》1996,74(5):386-399
Data on body composition in conjunction with reference centiles are helpful in identifying the severity of growth and nutritional disorders in infancy and for evaluating the adequacy of treatment given during this important period of rapid growth. Total body fat (TBF) and fat-free mass (FFM) were estimated from total body electrical conductivity (TBEC) measurements in 423 healthy term Caucasian infants, aged 14-379 days. Cross sectional age, weight, and length related centile standards are presented for TBF and FFM. Centiles were calculated using Altman's method, based on polynomial regression and modelling of the residual variation. The TBF percentage steeply increased during the first half year of life, and slowly declined beyond this age. Various simple TBEC derived anthropometric prediction equations for TBF and FFM are available to be used in conjunction with these standards. Regression equations for the P50 and the residual SD, depending on age, weight, or length, are provided for constructing centile charts and calculating standard deviation scores. 相似文献
47.
The STR system in the human phenylalanine hydroxylase gene: true fragment length obtained with fluorescent labelled PCR primers 总被引:5,自引:0,他引:5
J Zschocke CA Graham JJ McKnight NC Nevin 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(S407):41-42
We present a simple, fast, non-radioactive method for the analysis of the polymorphic short tandem repeat (STR) system in the human phenylalanine hydroxylase gene. Previously, sizing of the STR marker involved radiolabelling of PCR amplified fragments and resolution on denaturing polyacrylamide gels using M13 sequencing ladder as a standard. However, this method consistently gave sizes 2 bp longer than the known sequence. The fluorescent method presented here employs internal lane standards and enables accurate sizing of the fragments. To avoid confusion, we suggest that the true fragment lengths are used as reference values in the future. The analysis of STR alleles is valuable for population genetic studies and for targeted mutation screening in phenylketonuria (PKU). It can replace RFLP-based haplotype analysis for carrier detection, and we report its use for prenatal diagnosis in a Northern Irish family with PKU. The analysis of 250 Northern Irish chromosomes, including 128 PKU alleles, showed no significant difference between normal and PKU alleles, with fragment lengths of 238 and 242 bp most common in both groups. 相似文献
48.
TÜTÜNCÜOGLU SARENUR KANTAR MEHMET ÖZTÜRK VESILE YÜNTEN NILGÜN DUMAN YUSUF KULA SABAHATTIN ÖZGÜR TUGRUL 《Pediatrics international》1994,36(6):705-708
Moyamoya disease is a progressive disease which involves the internal carotid arteries and its branches bilaterally. The disease is reported both in adults and in children. Moyamoya disease is frequently seen in Japanese patients having certain human leucocyte antigen (HLA) haplotypes including HLA-Aw24, Bw46 and Bw54. Twin cases are rarely reported in the literature. We hereby present the first Turkish monozygotic twins with moyamoya disease whose HLA haplotypes are A2, A9, B21, Bw22, Bw4, Bw6, Cw3, and DR2, DR4, DRw52, DRw53, Dq7. The patients with advanced disease were given nifedipine and intravenous immunoglobulin (400mg/kg/d for 5 days). During the 11 months of follow-up, the patients were attack free. 相似文献
49.
Laércio Marques da Luz Neto Flávia Maria Nassar de Vasconcelos Jacqueline Elineuza da Silva Tiago Coimbra Costa Pinto Éverton Botelho Sougey Rosana Christine Cavalcanti Ximenes 《Jornal de pediatria》2019,95(1):18-26
Objective
To perform a systematic review of the literature for scientific evidence of possible differences in cortisol concentrations in adolescents with eating disorders.Source of data
Electronic searches were conducting in the PubMed, Scientific Electronic Library Online, Virtual Health Library, and Science Direct databases for articles published between 2007 and 2017 using the keywords, cortisol, hydrocortisone; eating disorders, bulimia, bulimia nervosa, anorexia, anorexia nervosa; adolescence, adolescent, adolescents.Synthesis of data
A total of 192 articles were found. After the analysis of the eligibility criteria using the PRISMA method, 19 articles were selected for the present review. Most studies were conducted in Europe. Adolescents diagnosed with anorexia nervosa were evaluated in all studies, except one, when other eating disorders were investigated. Blood was the means used for the determination of cortisol. In ten studies, cortisol levels were higher in the group with anorexia than the control group and a reduction in cortisol levels occurred in the adolescents after being submitted to nutritional recovery.Conclusions
Patients with eating disorders may have several clinical consequences, such as changes in body fat distribution, changes in bone mineral density, worsening of neurocognitive ability, and endocrine changes (e.g., hypercortisolemia), which in turn can lead to hyperglycemia, insulin resistance, hypertension, and increased risk of infections. The findings demonstrate that adolescents with eating disorders, especially anorexia nervosa, have increased cortisol levels, which are reduced after the treatment period. Further studies on differences in cortisol concentrations in adolescents with other eating disorders are needed, using different methods. 相似文献50.