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101.
Controlled release of lidocaine hydrochloride from the surfactant-doped hybrid xerogels. 总被引:2,自引:0,他引:2
We investigate the controlled release of lidocaine hydrochloride from the doped silica-based xerogels. In the xerogel preparation, tetraethoxysilane (TEOS), methyltriethoxysilane (MTES), and propyltriethoxysilane (PTES) are used as precursors, and a nonionic surfactant Igepal CO 720 is used as a dopant. The experimental results suggest that the release of lidocaine hydrochloride can be easily controlled by partially substituting TEOS with the organosilanes, and/or by adding the dopant. Adding the organosilane precursors lowers the release of both the drug and the surfactant in the order of TEOS, MTES/TEOS, and PTES/TEOS xerogels. The release from the PTES/TEOS xerogels is much lower than that from the other xerogels. The release of lidocaine hydrochloride is obviously suppressed by the addition of Igepal CO 720, while the release of Igepal CO 720 is slightly promoted by the addition of the drug. The overall release process is found to be diffusion-controlled, and the release behaviors can be well explained by considering the effects of the textual properties of the xerogels and the interactions among the drug, the surfactant, and the xerogel matrices. 相似文献
102.
K J Meador J L Thompson D W Loring A M Murro D W King B B Gallagher G P Lee J R Smith H F Flanigin 《Neurology》1991,41(6):869-872
Although there has been extensive examination of the behavioral and physiologic correlates of hippocampal theta activity in animals, the human literature consists of a single case study. We investigated the differential effects of four behavioral states on human hippocampal theta activity in 16 epilepsy surgery patients. Behavioral conditions included resting eyes closed (RC), resting eyes open (RO), eyes open with auditory word activation (AW), and eyes open with visuospatial activation (VS). Hippocampal theta activity decreased during both RO and VS compared to both RC and AW. There were reciprocal changes in delta activity. Comparisons of RO to VS and of RC to AW were nonsignificant. The results demonstrate state-specific changes in human hippocampal theta and are consistent with the animal literature that relates hippocampal theta to sensorimotor integration and forebrain volitional mechanisms. 相似文献
103.
Paclitaxel with Cisplatin as Salvage Treatment for Patients with Previously Treated Advanced Transitional Cell Carcinoma of the Urothelial Tract 下载免费PDF全文
104.
RNA干扰基因敲除MAGE-1在恶性胶质瘤U87细胞中的初步研究 总被引:4,自引:4,他引:0
目的:通过构建抑制MAGE-1的短片段双链核糖核酸(siRNA)表达载体,鉴定其在人恶性胶质瘤细胞系U87细胞中对MAGE.1基因表达的干涉作用。方法:化学合成2对编码短发夹RNA序列的靶向MAGE—1基因寡核苷酸链,克隆至经BglⅡ、HindⅢ双酶切的pSUPER载体上,重组构建核糖核酸干扰(RNAi)质粒载体。利用RT-PCR、流式细胞术和荧光显微镜,检测经稳定转染后胶质瘤U87细胞中MAGE-1的表达,以了解siRNA的干涉效果。结果:重组构建的pSUPER—MAGE—1载体经双酶切、电泳及插入基因片段序列分析,表明寡核苷酸链成功地插入至预计位点,且序列与预期完全一致。稳定转染后G418筛选出的U87多克隆细胞MAGE-1的表达经RT—PCR、流式细胞术和荧光显微镜检测,2对siRNA均有较明显的干扰作用。结论:载体的成功构建并能对U87细胞中的MAGE—1分子进行RNAi,为进一步研究MAGE—1在肿瘤中的作用,分析基因功能,展开肿瘤基因治疗奠定了基础。 相似文献
105.
Robert N. Page Lee Dittrich Roy King Fouad Boulos David L. Page 《Journal of cutaneous pathology》2009,36(11):1206-1209
Originally described by Rosen in 1983, syringomatous nipple adenoma (SAN) is a tumor of disputed histogenesis, which can be problematic both diagnostically and therapeutically. 1 It is a benign primary tumor of breast epithelium with histology similar to that of the syringoma. In the current case, we describe a 40-year-old female with this lesion occurring within a supernumerary breast. This case represents, to our knowledge, the first such reported case, and represents a significant finding as its presence could lend some confusion as to whether or not this represents a benign primary process of breast or a potentially infiltrative tumor of the skin. 相似文献
106.
膀胱肿瘤2350例临床病理学特点分析 总被引:1,自引:0,他引:1
目的 探讨膀胱肿瘤的发病现状、总体趋势和病理特点.方法 整理1980-2007年2350例膀胱肿瘤病理档案,分为1980-1989、1990-1999和2000-2007年3个时间段.应用SPSS 13.0软件分析3时间段患者性别、年龄及肿瘤组织学类型间的关系.结果 2350例膀胱肿瘤中男1854例,女496例.良性92例,恶性2258例,膀胱恶性肿瘤的发病人数逐年上升.发病高峰年龄从50~69岁推迟到60~79岁.1980-1989、1990-1999和2000-2007年3个时间段中男、女恶性肿瘤病例数分别为524例和113例(4.64:11 00)、589例和164例(3.59:1.00)、675例和193例(3.50:1.00),男性约为女性的3.80倍;3时间段男性发生膀胱尿路上皮癌年龄分别为(57.5±11.7)、(62.6±12.3)、(65.9±11.3)岁,女性分别为(58.7±13.6)、(60.7±12.1)、(65.8±12.0)岁,男女各年龄段分别比较差异有统计学意义(P<0.05).男性发生鳞状细胞癌、尿路上皮癌和腺癌年龄分别为(68.05±9.7)、(59.85±14.1)、(63.4±9.9)岁,差异有统计学意义(P相似文献
107.
108.
109.
Seunghan Ha Minhee Lee Onseok Lee Gunwoo Lee Jeayoung Kim Jongsub Moon Mingi Kim Chilhwan Oh 《Skin research and technology》2009,15(2):200-213
Background/aims: The objective and quantitative assessment of the skin is important in medical and cosmeceutical research. Assessment of color is an important element for analyzing the surface of the skin, which is usually determined subjectively by a doctor or using color analysis devices. These devices, however, cannot provide correct color information because color is construed from the mean value of the observation region, and analysis of color distribution is impossible. The purpose of this paper is to develop an objective analysis method to permit skin color measurement of each pixel unit of an image and analyze the distribution of skin surface color. Methods: The Skin Color Distribution Analyzer (SCDA) is an analysis method newly developed at the Research Institute for Skin Image at Korea University. The SCDA system presented in this paper performed a novel form of quantitative and objective analysis of skin color distribution using each pixel color model parameter found in image wavelength information. In this paper, distribution analysis was conducted on normal skin and skin lesions and skin affected by artificially induced irritant contact dermatitis and pigmented nevous. The method selected a grade using a color model parameter. Twenty healthy Korean males participated in this study. A comparative study of the eight anatomical areas was performed, including the exposure and non‐exposure parts and the medial aspect and the lateral aspect of the forearm. A reliability test for the SCDA system was also conducted with a spectrometer (SPEC) using the color analysis method. Results: Each skin lesion was precisely segmented by grade and each parameter hada different statistical significance for results of analysis of distribution in pigmented nevous and the artificially induced irritant contact dermatitis. Parameters L*, b*, a*, and EI showed salient traits. Showed resemble measured result in the SCDA system and the SPEC of normal skin. The exposed site, in comparison with the non‐exposed site, showed a notable difference in the L* parameter and a significant statistical difference in the x and z parameters, except b*. The comparison of the medial and lateral aspects of the forearm showed a notable difference in the L* parameter and a significant statistical difference in the parameters except y and b*. In the reliability test result using the SCDA system and the SPEC, the SCDA system was highly reliabile in terms of the CV value in all color model parameters. Conclusions: The color distribution analysis method using the SCDA system has revealed an aspect that the existent method of medical research has not shown, and is considered to be more reliable than other methods. This method can provide better study findings because it can be applied to other fields in addition to the medical science field and the ripple effect is thought to be bigger in other science field too. 相似文献
110.