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951.
乳腺病变组织中BcL-2,p53蛋白的表达 总被引:1,自引:1,他引:0
目的 观察 Bcl- 2 ,p5 3蛋白在浸润前系列乳腺病变(包括正常乳腺组织、导管增生、不典型导管增生、小叶增生、导管原位癌 )组织中的表达 .方法 采用免疫组化方法检测15例正常乳腺组织、18例导管增生、10例不典型导管增生(atypical ductal hyperplasia,ADH)、10例小叶增生 ,45例导管原位癌 (ductal carcinoma in situ,DCIS)的 Bcl- 2和 p5 3蛋白的表达 .结果 Bcl- 2蛋白在正常乳腺组织、导管增生、ADH、小叶增生组织中均阳性 ,而 p5 3蛋白染色阴性 .DCIS病例中 ,Bcl- 2蛋白表达阳性 34例 (76 % ) ,而 p5 3蛋白阳性 11例(2 4% ) .Bcl- 2蛋白表达与 DCIS组织学分级密切相关 (P<0 .0 1) ,6 7% DICS病例表现为 Bcl- 2 + / p5 3-表达表型 ,还有33%不同于正常的表型 (包括所有 Bcl- 2 - / p5 3+表型 )多代表差分化病例 .结论 Bcl- 2蛋白在正常乳腺组织、导管增生、ADH、小叶增生组织中均有表达且高于乳腺 DCIS.大部分DCIS病例表现为 Bcl- 2 + / p5 3-表型 ,与正常乳腺上皮、良性增生病变一致 相似文献
952.
黎宇 《山东医科大学学报(社会科学版)》2000,14(1):24-27,81
随着科技迅速发展,人在自然面前有了更多的“自由”,但与此同时,“全球问题”的出现又时时困扰着人们。人类要摆脱“困境”,更大限度地获得自由,迫切需要从认识上、实践中摆脱正人与自然的关系,自然地把改造自然和改造人自身结合起来,实现从必然王国向自由王国的飞跃。 相似文献
953.
954.
针对现有的卷积神经网络在肝脏图像分割上精度较低的问题,提出了一种以U-Net网络模型为基础的分割算法。将多头自注意力机制引入到U-Net网络的跳跃连接中,在编码器部分使用空洞卷积,采用混合损失函数从而提高分割精度。在LITS数据集上通过实验结果表明,利用本文方法进行肝脏分割与传统U-Net方法相比Dice系数提升3.3%,平均交并比提升了2.4%,平均像素准确率提升了3.66%。 相似文献
955.
956.
目的:研究安乃近溶液弄粘膜吸收规律。方法:以大鼠在体鼻循环法为实验模型,考察循环液的体积、流速等对安乃近弃枯膜吸收的影响。并在体积、流速确定的条件下,考查循环液浓度不同时,安乃近鼻粘膜吸收规律。结果:循环液体积越大,单位时间内粘膜吸收百分率越小;当流速较小时,随着流速的增加,吸收速度常数K增大,流速超过2 . 0 ml · min-1后,K显著减小;以循环液体积为3 ml,流速2.0 ml"min-1,考察了50,100,150,200 g·L-1安乃近溶液弄粘膜吸收规律,表明不同浓度的安乃近鼻粘膜吸收速度为一常数。结论:安乃近溶液鼻粘膜吸收机制为被动扩散,吸收符合一级动力学,吸收速度常数K为0.022 19 min-1 。 相似文献
957.
Van Leeuwen YD Düsman H Mol SS Pollemans MC Drop MJ Grol RP Van Der Vleuten CP 《Advances in health sciences education : theory and practice》1997,2(1):61-70
Objectives: The relation between the content of postgraduate training for general practice and the outcome in terms of the growth in knowledge of trainees was investigated. The training variables included were: (1) the number of patients seen per day, (2) the trainer, (3) the practice and (4) the theoretical curriculum.Methods: Subjects were 58 trainee-trainer pairs. Growth in knowledge was assessed by two written tests administered with eight months interval. Training variables were evaluated by means of questionnaires and logbook-registration. The correlation was explored between each of the training variables and the knowledge tests scores. To correct for interactional effects, a step-wise multiple regression analysis was performed with the second test as dependent variable and the first test as well as the training variables as independent variables.Results: Significant growth in knowledge was demonstrated. Non of all training variables investigated explained the variance in scores on the second test equally good or better than the scores on the entry test.Conclusions: The impact of the separate training-components on the growth in knowledge, remains unclear. We may speculate, that the sort of knowledge assessed with the written literature based true/false test is different from the sort of knowledge transferred during every day training: evidence based knowledge versus experience based knowledge. Equally valid is the conclusion that these findings fit into the theory that in adult learning the outcome is more learner than teacher dependent.This revised version was published online in September 2005 with corrections to the Cover Date. 相似文献
958.
Marttin Emmeline Verhoef J. Coos Cullander Christopher Romeijn Stefan G. Nagelkerke J. Fred Merkus Frans W. H. M. 《Pharmaceutical research》1997,14(5):631-637
Purpose. To visualize the transport pathway(s) of high molecular weight model compounds across rat nasal epithelium in vivousing confocal laser scanning microscopy. Furthermore, the influence of nasal absorption enhancers (randomly methylated -cyclodextrin and sodium taurodihydrofusidate) on this transport was studied.
Methods. Fluorescein isothiocyanate (FITC)-labelled dextrans with a molecular weight of 3,000 or 10,000 Da were administered intranasally to rats. Fifteen minutes after administration the tissue was fixed with Bouin. The nasal septum was surgically removed and stained with Evans Blue protein stain or DiIC18(5) lipid stain prior to visualization with the confocal laser scanning microscope.
Results. Transport of FITC-dextran 3,000 across nasal epithelium occurred via the paracellular pathway. Endocytosis of FITC-dextran 3,000 was also shown. In the presence of randomly methylated -cyclodextrin 2% (w/v) similar transport pathways for FITC-dextran 3,000 were observed. With sodium taurodihydrofusidate 1% (w/v) the transport route was also paracellular with endocytosis, but cells were swollen and mucus was extruded into the nasal cavity. For FITC-dextran 10,000 hardly any transport was observed without enhancer, or after co-administration with randomly methylated -cyclodextrin 2% (w/v). Co-administration with sodium taurodihydrofusidate 1% (w/v) resulted in paracellular transport of FITC-dextran 10,000, but morphological changes, i.e. swelling of cells and mucus extrusion, were observed.
Conclusions. Confocal laser scanning microscopy is a suitable approach to visualize the transport pathways of high molecular weight hydrophilic compounds across nasal epithelium, and to study the effects of absorption enhancers on drug transport and cell morphology. 相似文献
959.
Serotonin (5-HT) nerve terminals innervate sympathetic preganglionic neurons of the intermediolateral cell column (IML); however, neither the depolarization-induced release of 5-HT nor the presence of presynaptic modulatory autoreceptors have been directly studied in this system. We used in vitro superfusion of the microdissected intermediate area (including the intermediolateral cell column, intercalated nucleus, and central autonomic nucleus) of the rat thoracic spinal cord to measure basal and stimulated release of preloaded [3H]5-HT. Elevated K+ evoked a concentration- and Ca2+ dependent release of [3H]5-HT. Exogenous 5-HT and the 5-HT1B agonist, CGS-12066B, both decreased the K+-stimulated release of [3H]5-HT. A 5-HT1B antagonist (methiothepin) blocked the 5-HT- and the CGS-12066B-induced inhibition of K+-evoked release of [3H]5-HT. A 5-HT1A antagonist (NAN-190) did not alter the inhibitory actions of exogenous 5-HT. Moreover, a 5-HT1A agonist (8-OH-DPAT), a 5-HT2A/2C agonist [(+/-)-DOI hydrochloride], and a 5-HT3 agonist (2-methyl-5-HT) did not alter the K+ evoked release of [3H]5-HT. These data demonstrate that 5-HT is released from the intermediate area of the rat thoracic spinal cord. The 5-HT receptor subtype involved in the inhibition of the evoked release of [3H]5-HT is of the 5-HT1B subtype. These findings may help clarify the complex role of 5-HT in spinal regulation of the sympathetic nervous system. © 1994 Wiley-Liss, Inc 1 This article is US Government work and, as such, is in the public domain in the United States of America. 相似文献
960.