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991.
992.
尼日利亚翼状胬肉治疗状况的回顾性分析 总被引:3,自引:3,他引:0
Ernest N.Onwasigwe Ifeoma R.Ezegwui 《国际眼科杂志》2006,6(3):552-554
目的:总结尼日利亚翼状胬肉的治疗现状。方法:选择1999-01/2002-12的4a期间的翼状胬肉手术患者,所有病例都来自于尼日利亚Enugu市的尼日利亚大学教学医院和Ebrans临床中心。收集这些患者的生理数据、临床表现、手术方法和术后并发症等资料,应用6.1版EPI-INFO方法进行数据处理。共选择3种不同的手术方法:60眼单纯施行巩膜暴露术,42眼施行联合5-氟尿嘧啶(5-FU)的巩膜暴露术,22眼施行联合丝裂霉素C的巩膜暴露术。结果:72例(124眼)施行翼状胬肉切除术的患者,术后至少随访1a,包括男41例(56.9%),女31例(43.1%),男女比例为1∶0.8。术后复发率最高的在病变第III期(55.6%),最低在病变第I期(22.2%)。3种手术方法比较,复发率分别为65.0%、52%和13.6%。结论:在像尼日利亚这样的发展中国家,联合丝裂霉素的早期手术切除术,是一种安全性强、治疗费用低、方法简单且创伤小的治疗翼状胬肉的有效手段,值得推广。 相似文献
993.
994.
Image fusion is a process of combining information from multiple sensors. It is a useful tool implemented in the treatment planning programme of Gamma Knife Radiosurgery. In this paper we evaluate advanced image fusion algorithms for Matlab platform and head images. We develop nine level grayscale image fusion methods: average, principal component analysis (PCA), discrete wavelet transform (DWT) and Laplacian, filter - subtract - decimate (FSD), contrast, gradient, morphological pyramid and a shift invariant discrete wavelet transform (SIDWT) method in Matlab platform. We test these methods qualitatively and quantitatively. The quantitative criteria we use are the Root Mean Square Error (RMSE), the Mutual Information (MI), the Standard Deviation (STD), the Entropy (H), the Difference Entropy (DH) and the Cross Entropy (CEN). The qualitative are: natural appearance, brilliance contrast, presence of complementary features and enhancement of common features. Finally we make clinically useful suggestions. 相似文献
995.
Molecular determinants of cetuximab efficacy. 总被引:17,自引:0,他引:17
Daniel Vallb?hmer Wu Zhang Michael Gordon Dong Yun Yang Jim Yun Oliver A Press Katrin E Rhodes Andy E Sherrod Syma Iqbal Kathleen D Danenberg Susan Groshen Heinz-Josef Lenz 《Journal of clinical oncology》2005,23(15):3536-3544
PURPOSE: To investigate whether mRNA expression levels of cyclin D1 (CCND1), cyclooxygenase 2 (Cox-2), epidermal growth factor receptor (EGFR), interleukin 8 (IL-8), and vascular endothelial growth factor (VEGF), all members of the EGFR signaling pathway, are associated with clinical outcome in patients with EGFR-expressing metastatic colorectal cancer (CRC) treated with cetuximab. PATIENTS AND METHODS: Thirty-nine patients with metastatic CRC, refractory to both irinotecan and oxaliplatin, were enrolled on IMCL-0144 and treated with single-agent cetuximab. The intratumoral mRNA levels of CCND1, Cox-2, EGFR, IL-8, and VEGF were assessed from paraffin-embedded tissue samples using laser-capture microdissection and quantitative real-time polymerase chain reaction. RESULTS: There were 21 women and 18 men with a median age of 64 years (range, 35 to 83 years). Higher gene expression levels of VEGF were associated with resistance to cetuximab (P = .038; Kruskal-Wallis test). The combination of low gene expression levels of Cox-2, EGFR, and IL-8 was significantly associated with overall survival (13.5 v 2.3 months; P = .028; log-rank test). Both findings were independent of skin toxicity that was itself significantly correlated to survival. Patients with a lower mRNA amount of EGFR had a longer overall survival compared with patients that had a higher mRNA amount (7.3 v 2.2 months; P = .09; log-rank test). Patients with lower expression of Cox-2 had a significantly higher rate of grade 2 to 3 skin reactions under cetuximab treatment. CONCLUSION: This pilot study suggests that gene expression levels of Cox-2, EGFR, IL-8, and VEGF in patients with metastatic CRC may be useful markers of clinical outcome in single-agent cetuximab treatment. 相似文献
996.
G. B. Slepchenko L. S. Anisimova V. F. Slipchenko E. V. Mikheeva N. P. Pikula 《Pharmaceutical Chemistry Journal》2005,39(3):166-168
Rapid voltammetric procedures for the determination of water-soluble vitamins C, B1, and B2, fat-soluble vitamin E (α-tocopherol acetate), and quercetin in bioactive food additives have been developed. The systematic error (i.e., correctness) of the proposed procedures was evaluated using certified reference materials and the additive recovery tests, which gave the following limiting metrological characteristics: relative error, 25 %; reproducibility, 28 %; convergence, 22 %. The full analysis time (with sample preparation) did not exceed 2 hours. Voltammetric determinations under optimum conditions can be performed in the automated regime controlled by a computer according to the specially developed software.__________Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 3, pp. 54 – 56, March, 2005. 相似文献
997.
L. A. Trukhacheva V. I. Levina A. P. Arzamastsev N. B. Grigor'ev V. G. Granik 《Pharmaceutical Chemistry Journal》2005,39(6):296-299
The kinetics of alkaline hydrolysis of N-(5-nitro-2-thiazolyl)-2-thiophenylcarboxamide (tenonitrozole or atrican) has been studied by photometric and polarographic
techniques, and the thermodynamic parameters in the intermediate state of this process were determined. A mechanism explaining
the nitric oxide (NO) production during the hydrolytic decomposition of tenonitrozole is proposed. It is suggested that the
antiprotozoal and antimicrobial activity of this drug under anaerobic conditions is related to the formation of nitro radical
anions and NO. Under aerobic and microaerophilic conditions, the hydrolysis of tenonitrozole may lead to the formation of
a peroxynitrite anion, which is a strong cytotoxic agent.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 6, pp. 15 – 18, June, 2005. 相似文献
998.
999.
An unusual, elongated, refractile cell morphology was observed in keratinocytes cultured from three patients with non-lethalis forms of junctional epidermolysis bullosa (JEB). To determine whether these changes might be related to altered cell adhesion, keratinocyte strains established from one patient were examined for adhesive, structural, and functional characteristics. JEB keratinocytes expressed keratin tonofilaments, as determined by staining with AE1 monoclonal antibodies and direct observation of tonofilaments by electron microscopy. JEB keratinocytes showed diminished cell-substratum adhesions, judged by interference reflection microscopy. Areas of diminished cell-substratum adhesion corresponded to F-actin-rich cell adhesions (focal adhesions) and not to cellular areas that abundantly express hemidesmosomal antigens. Analysis of cell-substratum adhesion by electron microscopy revealed extensive areas of cell-substratum separation in JEB keratinocytes that were not present in normal keratinocytes maintained in serum-free medium. Normal keratinocytes displayed numerous regions of focal contact between the ventral plasma membrane and the culture substratum, but these structures were not seen in JEB keratinocytes. Bundled actin filaments (stress fibers) were greatly diminished in expected regions of cell-substratum adhesion in JEB keratinocytes and, instead, displayed disorganized individual filaments. The growth rate of JEB keratinocytes was quite slow in culture, with a population doubling time of 2.7 d versus 1.5 d for normal keratinocytes under identical conditions. JEB keratinocytes also displayed a reduced ability to aggregate into colonies upon exposure to medium with increased extracellular calcium. JEB keratinocytes thus display adhesive, structural, and functional abnormalities that suggest this cell type may be central to the pathogenesis of junctional epidermolysis bullosa. Study of affected keratinocytes could be important to characterize associated molecular pathologies. 相似文献
1000.