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141.
Hong L Miyamoto S Hashimoto N Tabata Y 《Journal of biomaterials science. Polymer edition》2000,11(12):1357-1369
The objective of this study is to examine whether or not bone formation at a skull bone defect induced by gelatin microspheres incorporating transforming growth factor (TGF)-beta1 is promoted by prevention of fibrous tissues into the defect. The 6-mm diameter bone defect of rabbit skulls was applied with gelatin microspheres incorporating TGF-beta1 or free TGF-beta1 and physically covered by a barrier membrane. When the bone formation at the defect was assessed 6 weeks postoperatively, combinational application of gelatin microspheres incorporating 0.1 microg of TGF-beta1 with the barrier membrane induced bone formation at the skull defect, in marked contrast to that of 0.1 microg of free TGF-beta1 and empty gelatin microspheres. Complete defect closure was histologically observed by the newly formed bone tissue. Without the barrier membrane, gelatin microspheres incorporating TGF-beta1 were less effective in inducing bone formation, whereas free TGF-beta1 and empty gelatin microspheres were ineffective. The skull defect was occupied by fibrous tissue infiltrated in place of bone tissue. The bone mineral density at the skull defect applied with gelatin microspheres incorporating TGF-beta1 plus the membrane was significantly higher than that of gelatin microspheres incorporating TGF-beta1 alone. The present data indicated that physical protection from the soft tissue infiltration enabled gelatin microspheres incorporating TGF-beta1 to synergistically enhance the osteoinductive ability at the skull defect. 相似文献
142.
143.
STUDY OBJECTIVES: Very few studies have evaluated narcolepsy in Asian countries, outside of Japan. Our goal was to study narcolepsy at the genetic, clinical and pathophysiological level in Korea. DESIGN: Prospective study of consecutive patients and age matched controls. Clinical data ascertained from the Stanford Sleep Inventory, Polysomnography and MSLT data, as well as clinical notes. High resolution DRB1 and DQB1 typing in all subjects and studies of CSF hypocretin-1 was also evaluated in a subset of patients. PARTICIPANTS AND SETTING: 20 patients diagnosed at St. Vincent and Korea University Hospitals (Seoul, Korea). 21 Korean control subjects. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: For narcoleptic subjects, mean age was 28.2 years old and 45% were female. Mean BMI was 23.9+/-3.4 kg/m2, a significantly higher value than that expected in an age- and sex-matched sample (p<0.01). All patients had sleepiness and cataplexy while the prevalence of other symptoms ranged from 60-75%. All but 2 subjects were HLA-DR15 (DR2), DQB1*0602 positive (90%). This high DQB1*0602 percentage compared with 24% DQB1*0602 positivity in 21 control Koreans. Protective effects were observed for the DQB1*0601 and DRB1*0406 alleles, Hypocretin (orexin) CSF studies were also performed in 6 cataplectic subjects, all of which had undetectable CSF hypocretin levels. Two of these subjects had started narcolepsy less than 1 year before analysis yet had undetectable hypocretin levels. CONCLUSION: These results illustrate the similarity of narcolepsy-cataplexy in Korea in comparisons with other more studied populations. We also identified a new potential HLA protective subtype, HLA-DRB1*0406. 相似文献
144.
Image reconstruction of anisotropic conductivity tensor distribution in MREIT: computer simulation study 总被引:2,自引:0,他引:2
We describe a novel method of reconstructing images of an anisotropic conductivity tensor distribution inside an electrically conducting subject in magnetic resonance electrical impedance tomography (MREIT). MREIT is a recent medical imaging technique combining electrical impedance tomography (EIT) and magnetic resonance imaging (MRI) to produce conductivity images with improved spatial resolution and accuracy. In MREIT, we inject electrical current into the subject through surface electrodes and measure the z-component Bz of the induced magnetic flux density using an MRI scanner. Here, we assume that z is the direction of the main magnetic field of the MRI scanner. Considering the fact that most biological tissues are known to have anisotropic conductivity values, the primary goal of MREIT should be the imaging of an anisotropic conductivity tensor distribution. However, up to now, all MREIT techniques have assumed an isotropic conductivity distribution in the image reconstruction problem to simplify the underlying mathematical theory. In this paper, we firstly formulate a new image reconstruction method of an anisotropic conductivity tensor distribution. We use the relationship between multiple injection currents and the corresponding induced Bz data. Simulation results show that the algorithm can successfully reconstruct images of anisotropic conductivity tensor distributions. While the results show the feasibility of the method, they also suggest a more careful design of data collection methods and data processing techniques compared with isotropic conductivity imaging. 相似文献
145.
146.
R Hong 《Clinical immunology and immunopathology》1986,40(1):136-141
Correction of T-cell defects by either thymic hormone treatment or thymus transplantation has proven to be more difficult clinically than historically anticipated. Because the precise action of thymic hormones is unknown and because these hormones act upon post-thymic cells, therapeutic attempts may fail owing to lack of sufficient substrate population. Results of thymic transplantation suggest that this procedure may be best utilized for the treatment of mild T-cell defects, rather than as complete replacement treatment for severe deficiency. Future clinical trials of thymic transplantation or thymic hormone appear justified in narrowly circumscribed and well-characterized conditions. 相似文献
147.
Gye Won Kim Sung Youl Hong Soon Cheon Shin Sung Hee Lee Won Bae Kim 《Archives of pharmacal research》1987,10(1):18-24
Mouse monoclonal antibodies to Hepatitis B surface antigen(HBsAg) were prepared and their functional capabilities tested by the method of solid phase enzyme linked immuno sorbent assay(ELISA). HBsAg binding studies indicated that one monoclonal antibody 6E-1-1 bound more HBsAg at a faster rate than the other monoclonal antibodies. Also, for the binding inhibition studies with the selected monoclonal antibody 6E-1-1, one monoclonal antibody 8D-3-6 didn’t exhibit binding inhibition for HBsAg. Then, a simultaneous ELISA method was developed for the immunodiagnosis of HBsAg. Different combinations of two monoclonal antibodies as solid phase and horseradish peroxidase(HRPO) labeled phase were studied. The combination of monoclonal antibody of higher affinity constant (6E-1-1) immobilized in a solid phase and monoclonal antibody of lower affinity constant (8D-3-6) as a HRPO labeled phase was more sensitive when two monoclonal antibodies of different affinity constants for HBsAg were prepared. 相似文献
148.
A new tetrahydrofuran lignan, named henricine ( 1), was isolated from the stems of SCHISANDRA HENRYI. High resolution COSY spectrum was used in the structural elucidation. 相似文献
149.
Priyanka Sharma Guojun Wu Deeptha Kumaraswamy Natalie Burchat Hong Ye Yongjia Gong Liping Zhao Yan Y. Lam Harini Sampath 《Nutrients》2021,13(2)
7,8-Dihydroxyflavone (DHF) is a naturally occurring flavonoid that has been reported to protect against a variety of pathologies. Chronic administration of DHF prevents high-fat diet (HFD)-induced obesity in female, but not male, mice. However, the mechanisms underlying this sexual dimorphism have not been elucidated. We have discovered that oral DHF supplementation significantly attenuates fat mass, hepatic lipid accumulation, and adipose tissue inflammation in female mice. In contrast, male mice were not protected from adiposity, and had a paradoxical worsening of hepatic lipid accumulation and adipose tissue inflammation upon DHF supplementation. Consistent with these sexually dimorphic effects on body weight and metabolic health, 7,8-DHF induced early and stable remodeling of the female intestinal microbiome. DHF supplementation significantly increased gut microbial diversity, and suppressed potentially detrimental bacteria, particularly Desulfovibrionaceae, which are pro-inflammatory and positively associated with obesity and inflammation. Changes in the female gut microbiome preceded alterations in body weights, and in silico analyses indicated that these early microbial changes were highly predictive of subsequent weight gain in female mice. While some alterations in the intestinal microbiome were also observed in male DHF-supplemented mice, these changes were distinct from those in females and, importantly, were not predictive of subsequent body weight changes in male animals. The temporality of microbial changes preceding alterations in body weight in female mice suggests a role for the gut microbiome in mediating the sexually dimorphic effects of DHF on body weight. Given the significant clinical interest in this flavonoid across a wide range of pathologies, further elucidation of these sexually dimorphic effects will aid the development of effective clinical therapies. 相似文献
150.
Basnet Sulochana Frongillo Edward A. Nguyen Phuong Hong Moore Spencer Arabi Mandana 《Maternal and child health journal》2021,25(6):946-946
Maternal and Child Health Journal - The article “Factor Structure and Equivalence of Maternal Resources for Care in Bangladesh, Vietnam, and Ethiopia”, written by Sulochana Basnet,... 相似文献