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91.
92.
Purpose Desmoplastic infantile gangliogliomas (DIG) are rare benign intracranial neoplasms of early childhood with involvement of
superficial cerebral cortex and leptomeninges. The purpose of the study was to determine the alterations in metabolite ratios
occurring in the neoplasm and combine with magnetic resonance (MR) imaging features to narrow down the diagnosis.
Methods MR imaging sequences include T1- and T2-weighted sequences, fluid-attenuated inversion recovery sequences, and post-gadolinium-contrast
T1-weighted imaging. Single-voxel short TE 1H MR spectroscopy was used to study the changes in metabolite ratios in the tumor.
Results Comparison of metabolite ratios between normal brain tissue and tumor-affected region showed lower N-acetyl aspartate to creatine (Cr; 1.58 vs.1.28), higher choline to Cr (0.82 vs.2.03), and no significant change in myo-inositol
to Cr (0.42 vs.0.39).
Conclusion MR spectroscopy and imaging provide valuable information in the diagnosis of DIG. 相似文献
93.
94.
An attempt has been made to localize ranitidine loaded microspheres in the stomach by magnetic means. Since ranitidine undergoes metabolism by microbial enzymes in the intestine, it is ideal to localize the controlled drug delivery system within the stomach to get uniform release and absorption of the drug for the desired period. Gelatin magnetic microspheres loaded with 9.1, 17.9, 26.3 and 33.3% w/w of ranitidine hydrochloride were prepared by emulsification-cross linking technique. The formulated microspheres were characterized by magnetite content, particle size and in vitro drug release. The efficiency of microspheres to be localized in the stomach is tested in vivo in rats. The prepared microspheres were spherical and had a size distribution from 10 to 105 microm. The in vitro study revealed the capability of microspheres to release the drug over a period of 8 to 12 hours, depending on drug loading. The release was found to be diffusion controlled and followed fickian diffusion principle. The in vivo study showed the efficiency of microspheres to be retained in the stomach over a period of 8 hours. 相似文献
95.
Muller N Steele M Balaji KA Krishna M Berman AP Robertson J Vail J 《Tropical doctor》2007,37(3):133-135
The objective of this study was to assess the effect of the use of a manually operated needle remover on sharps-waste management practices in clinical settings in India - specifically, evaluating its acceptability and performance. Thirty-one Balcan Mini-Destructor needle removers were introduced into seven health facilities in two cities in India - Delhi and Jaipur. One hundred and nineteen health workers, including auxiliary nurse midwives, nurses, and laboratory staff, used the device. Data were prospectively collected by observation and interview on device usage, malfunction and acceptability over a 23-week period. Focus group discussions on current practices were conducted prior to study initiation and, after completion, on device acceptability and performance. The manual needle remover was well accepted. Devices were seen as easy to use and durable. In total, 88,719 needles were removed. In conclusion, the needle-remover device was considered an acceptable method of preventing needle reuse and isolating infectious sharps waste in clinical settings. 相似文献
96.
Donald Cheatem Balaji B. Ganesh Eryn Gangi Chenthamarakshan Vasu Bellur S. Prabhakar 《Clinical immunology (Orlando, Fla.)》2009,131(2):260-270
Abnormalities in DC function are implicated in defective immune regulation that leads to type-1 diabetes (T1D) in NOD mice and humans. In this study, we used GM-CSF and Flt3-L to modulate DC function in NOD mice and observed the effects on T1D development. Treatment with either ligand at earlier stages of insulitis suppressed the development of T1D. Unlike Flt3-L, GM-CSF was more effective in suppressing T1D, even when administered at later stages of insulitis. In vitro studies and in vivo adoptive transfer experiments revealed that CD4+CD25+ T cells from GM-CSF-treated mice could suppress effector T cell response and T1D. This suppression is likely mediated through enhanced IL-10 and TGF-β1 production. Adoptive transfer of GM-CSF exposed DCs to naive mice resulted in an expansion of Foxp3+ T cells and a significant delay in T1D onset. Our results indicate that GM-CSF acted primarily on DCs and caused an expansion of Foxp3+ Tregs which delayed the onset of T1D in NOD mice. 相似文献
97.
S. M. Balaji 《Journal of maxillofacial and oral surgery》2010,9(3):224-296
Fibrous histiocytoma is a tumor composed of a mixture of fibroblastic and histiocytic cells. These lesions most often arise
on the skin, but may rarely occur in soft deep tissues. The diagnosis of FH may be clinically difficult when the lesion is
located in the deep tissues, and is frequently confirmed after local excision. The most important diagnostic necessity is
the separation of this tumor from aggressive forms of fibrohistiocytic neoplasms. We present a unique case of malignant fibrous
histiocytoma developing in left buccal mucosa very near to the surgical margin from which a benign fibrous histiocytoma of
the mandible was excised 3 years earlier in a 31 year old female. Clinical and histopathological evidence were not sufficient
to establish link between these two processes. This article aims to describe the case and discuss the findings. 相似文献
98.
Rathnavel Thillaikarasi Jayaram Balaji Bhawna Gupta Vadivel Ilayarja Nandimandalam Venkata Vani Balachander Vidula Balasubramaniam Saravanan Irulandy Ponniah 《Journal of maxillofacial and oral surgery》2010,9(3):310-313
Ameloblastoma is a locally aggressive benign epithelial odontogenic tumor, while unicystic ameloblastoma is a relatively less
aggressive variant. Although rare in unicystic or cystic ameloblastoma, granular cell change in ameloblastoma is a recognized
phenomenon. The purpose of the present article is to report a case of cystic granular cell ameloblastoma in 34-year old female. 相似文献
99.
100.
Ulery BD Phanse Y Sinha A Wannemuehler MJ Narasimhan B Bellaire BH 《Pharmaceutical research》2009,26(3):683-690
Purpose To demonstrate that polyanhydride copolymer chemistry affects the uptake and intracellular compartmentalization of nanospheres
by THP-1 human monocytic cells.
Methods Polyanhydride nanospheres were prepared by an anti-solvent nanoprecipitation technique. Morphology and particle diameter were
confirmed via scanning election microscopy and quasi-elastic light scattering, respectively. The effects of varying polymer
chemistry on nanosphere and fluorescently labeled protein uptake by THP-1 cells were monitored by laser scanning confocal
microscopy.
Results Polyanhydride nanoparticles composed of poly(sebacic anhydride) (SA), and 20:80 and 50:50 copolymers of 1,6-bis-(p-carboxyphenoxy)hexane (CPH) anhydride and SA were fabricated with similar spherical morphology and particle diameter (200
to 800 nm). Exposure of the nanospheres to THP-1 monocytes showed that poly(SA) and 20:80 CPH:SA nanospheres were readily
internalized whereas 50:50 CPH:SA nanospheres had limited uptake. The chemistries also differentially enhanced the uptake
of a red fluorescent protein-labeled antigen.
Conclusions Nanosphere and antigen uptake by monocytes can be directly correlated to the chemistry of the nanosphere. These results demonstrate
the importance of choosing polyanhydride chemistries that facilitate enhanced interactions with antigen presenting cells that
are necessary in the initiation of efficacious immune responses. 相似文献