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101.
102.
Heng-Shuen Chen Fei-Ran Guo Chien-Tsai Liu Yue-Joe Lee Jye-Horng Chen Chia-Chin Lin Sheng-Mou Hou Bor-Shen Hsieh 《International journal of medical informatics》1998,50(1-3):59-68
National Taiwan University College of Medicine (NTUCM) introduced small groups of teaching and basic-clinical integrated courses for medical students in 1992. By using computer network and multimedia techniques, this study tried to overcome barriers to learning in small group teaching. The Department of Medical Informatics of NTUCM established campus networking and computer classrooms and provided Internet and intranet network services including mail, netnews, bulletin board systems (BBS), world wide web (WWW), gopher, ftp and local file servers. To implement an interactive learning environment, the authors first tried mail lists, newsgroups and BBS. Next an integrated learning system prototype on the WWW was developed to provide functions including online syllabus, discussion boards simulated to BBS, online talk, interactive case studies, virtual classroom with video on demand (VOD) and Internet medical resources. The results showed that after the medical students completed the required course of medical informatics and had good network access using a network to communicate with each other became a daily practice. In the future, the system will extend to the tutoring of clinical practice and continuing medical education. The authors expect a national medical education network and more international cooperation and exchange. 相似文献
103.
重组蛇毒纤溶因子rFⅡ偶联到聚氨酯表面及其纤溶活性评价 总被引:1,自引:1,他引:1
目的:通过聚氨酯表面偶联重组蛇毒纤溶因子rF Ⅱ来提高其纤溶活性。方法:在聚氨酯(PU)表面上涂覆含羧基硬段的聚氨酯溶液(PU1)制备羧基化表面聚氨酯(CPU),并用次甲基蓝吸附法测定表面羧基含量;在CPU表面上用EDC接枝双端氨基聚乙二醇(PEG),并用滴定法测定该表面的PEG接枝量;在CPU-PEG表面用EDC偶联重组蛇毒纤溶因子(rF Ⅱ),并用放射性同位素法测定该表面的rF Ⅱ偶联量,最后用试管定量法评价样品的纤溶活性。结果:CPU表面羧基含量为6.9μmol/cm^2,CPU-PEG2k和CPU-PEG4k表面PEG含量分别为0.162和0.180μmol/cm^2,CPU-PEG2k-^125Ⅰ-rFⅡ和CPU-PEG4k^125Ⅰ-rFⅡ表面rF Ⅱ含量分别为13.6和38.9ng/cm^2,与对照样品相比都有很大的提高。纤溶活性评价表明,所有偶联rF Ⅱ样品的纤溶活性都有提高,抗血栓性能得到有效改善。结论:具有PEG间隔臂偶联rF Ⅱ的样品其纤溶活性比没有PEG间隔臂的样品更优,采用PEG4k间隔臂偶联rF Ⅱ样品的纤溶活性为最高。 相似文献
104.
David E. Clapham Louis J. de Felice 《Pflügers Archiv : European journal of physiology》1976,366(2-3):273-276
Summary The small signal impedance of the frog node is calculated for frequencies from 1 Hz to 10,000 Hz and transmembrane potentials from –80 mV to –30 mV by linearizing the voltage clamp equations of Dodge [7] and Hille [8]. The modulus of the impedance is presented for the total system, and separately for the potassium and sodium systems as a function of frequency and voltage. There is a broad resonance in the total impedance with a voltage-dependent peak frequency. At 22°C, in the range –75 mV to –45 mV, the peak frequencies occur between 50 and 500 Hz. Removing the potassium system leaves a relatively shapr resonance centered around 200 Hz at –45 mV. 相似文献
105.
《Immunobiology》2022,227(6):152298
PLPPs (Phospholipid phosphatases) are widely expressed in different human tissues, regulate cell signal transduction, and are overexpressed in cancers such as gliomas, pancreatic adenocarcinoma, lung adenocarcinoma, and so on. As a member of the PLPP family, PLPP2 (phospholipid phosphatase 2) plays a vital role in the occurrence and development of breast cancer, but its mechanism is still unclear. Our research found that PLPP2 was overexpressed in breast cancer, and the higher expression level of PLPP2 showed a worse prognosis for breast cancer patients. Further analysis showed that overexpression of PLPP2 affected the expression of CDC34 (cell-division cycle 34), LSM7 (Like-Smith 7), and SGTA (small glutamine-rich tetratricopeptide repeat-containing protein alpha) through EMT (epigenetic-mesenchymal transition) related pathways to promote the occurrence and development of breast cancer. In vitro, silencing PLPP2 significantly reduced the proliferation, invasion, and migration abilities of human breast cancer cells MDA-MB-231. ER+ is a common subtype of breast cancer. Furthermore, we found that the overexpression of PLPP2 was significantly related to the poor prognosis of ER+ breast cancer. These results indicate that PLPP2 has value as a potential therapeutic target for breast cancer, especially for ER+ breast cancer. 相似文献
106.
利用荧光组织化学和组织学染色连续在同一切片上显示的方法,观察了5只大鼠整个心脏和7只大鼠心房的连续切片。大鼠心脏的小强荧光细胞为圆形、卵圆形和不规则形。它们在心脏主要呈密集成团、簇状或素条状细胞群,以及散在存在的细胞。成年大鼠心脏小强荧光细胞的数量为442~664个,其中86~92%位于心房外膜,而且主要位于心房背侧几个区域。心内膜未发现小强荧光细胞;其他部位这种细胞很少。小强荧光细胞和心壁的神经节分布区域相类似。但是有的神经节并没有小强荧光细胞。部分小强荧光细胞邻近心壁的小血管。这种细胞和传导系统没有明显的形态学接触。 相似文献
107.
Paolo Lionetti Jo Spencer Emma J. Breese Simon H. Murch Jacqueline Taylor Thomas T. Macdonald 《European journal of immunology》1993,23(3):664-668
Staphylococcus aureus enterotoxin B (SEB) was added to explants of fetal human intestine in organ culture or administered into the lumen of fetal small intestine prior to culture. Both routes produced a massive increase in lamina propria T cells expressing Vβ33, and to a lesser extent, those expressing Vβ5 and Vβ12. SEB-activated lamina propria T cells produced interleukin-2 and interferon-Y and T cell activation was accompanied by tissue damage, which was inhibited by FK506. 相似文献
108.
R.A. BRONSON G.W. COOPER D.L. ROSENFELD 《American journal of reproductive immunology (New York, N.Y. : 1989)》1982,2(4):222-224
ABSTRACT: Sera from men at risk for immunity to spermatozoa were screened for antisperm antibodies by immunobead binding following passive antibody transfer to antibody-free sperm of fertile donors. The percent motile sperm after incubation in diluted antibody positive serum in the presence of complement was compared with the regional distribution of immunoglobulins bound to the sperm surface. The extent of complement-mediated sperm immobilization varied with immunoglobulin class and with the location of antibody bound to the sperm surface. Tests utilizing complement-mediated immobilization of sperm are insensitive to the presence of antibodies of IgG and IgA classes that are directed against the head, the distal one-fifth of the sperm tail principal piece, or the tail end piece. A high degree of immobilization was found only when IgG binding occurred on the distal two-fifths to three-fifths of the principal piece of the tail or when IgM bound to the sperm tail end piece. 相似文献
109.
Enhancement of the speed and sensitivity of an ELISA technique was achieved by doing it on a polystyrene microtiter plate preactivated by a simple photochemical reaction. Immobilization of Epicoccum nigrum antigen (allergenic antigen) or goat anti-rabbit IgG onto the photoactivated plates was found to occur in only 45 min with higher binding than that obtained through adsorption during the same period onto the untreated surface. Nearly 1.5-2-folds higher readings were obtained when the ELISA was carried out with the solid phase prepared on the photoactivated surface rather than on the untreated surface. Moreover, solid phases prepared on the activated surface could detect IgE (E. nigrum antibody) even at 1/50 (v/v) dilutions, whereas a solid phase prepared on the untreated surface failed to do so. Around three times higher ELISA values were obtained in the activated plate than the untreated plate when IgE was diluted to 1/5 (v/v). Such photoactivated surface could be of great importance in diagnostic tests involving the ELISA technique particularly to confirm false negative cases and for other immunoassays such as radioimmunoassay procedures. 相似文献
110.