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91.
92.
Both cisplatin (CDDP) and leucovorin (LV) have been shown to enhance cytotoxicity of 5-fluorouracil (FUra) against murine and human neoplasms by increasing intracellular reduced folate concentrations. We were interested in their use in a combination to inhibit non-small cell lung cancer (NSCLC) cell growth and therefore conducted an in vitro study to investigate the cytotoxic activities of combinations of CDDP plus FUra, with and without LV (20 microM), against seven NSCLC cell lines. A tetrazolium assay with application of the classical isobole method was used to test drug combinations. We found that LV enhanced FUra but not CDDP cytotoxicity and that the degree of enhancement was negatively correlated with the effect of FUra. There was an overall additive combination effect of CDDP plus FUra, although there may be synergy at higher effect levels. There was synergy to a combination of CDDP, FUra, and LV, presumably primarily related to the synergistic effects of adding LV to FUra. In summary, LV and CDDP enhanced FUra cytotoxicity in a complementary fashion and there was clear synergy of a combination of CDDP, FUra, and LV against a panel of NSCLC cell lines. Our in vitro results provide a rationale for controlled clinical studies of this three-drug regimen in patients with NSCLC.  相似文献   
93.
Collected ratings of communication ease and of engagement for 95 deaf junior and senior high school students (aged 12–21 yrs) in a large, urban, multiethnic school for the deaf. Ratings were made by the students' English teachers and by the students themselves. High teacher ratings for communication ease and engagement were associated with high academic achievement as measured by the Stanford Achievement Test. High student ratings for communication ease were also associated with academic achievement. The 2 best predictors of academic achievement were student-rated communication ease and teacher-rated engagement. Findings suggest that it is important for teachers to be sensitive to the level of communication comfort of their students because students who enjoy easier communication may be more likely to be engaged, or more actively involved, in classroom learning and to demonstrate higher academic achievement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
94.
A patient who developed a mixed neuroendocrine carcinoma and adenocarcinoma at the site of a previous long-standing ileostomy is reported. The neuroendocrine features are documented by both ultrastructural and immunocytochemical findings. Carcinoma arising in an ileostomy site is rare but has been recorded in patients with long-standing ileostomies after colectomy for chronic inflammatory bowel disease, as in this patient. Neuroendocrine carcinoma developing in this setting apparently has not been described before, however.  相似文献   
95.
A case report of a 10-year old girl with a herniated disc is presented. The most significant symptoms were progressive scoliosis with a flat back and paravertebral muscle spasm. An absent H reflex on the left and an increased latency of the somatosensory-evoked potentials of the left posterior tibial nerve were found. The computed tomographic scan of the lumbar spine showed a large central left-sided disc protrusion at the L5-S1 level. Our case presents the youngest patient with documented intervertebral disc herniation and the only one with severe scoliosis and vertebral rotation. The curve was not structural because it improved with surgery and an orthosis was not necessary.  相似文献   
96.
An early step in the development of vertebrae, ribs, muscle, and dermis is the differentiation of the somitic mesoderm into dermomyotome dorsally and sclerotome ventrally. To analyze this process, we have developed an in vitro assay for somitic mesoderm differentiation. We show that sclerotomal markers can be induced by a diffusible factor secreted by notochord and floor plate and that heterologous cells expressing Sonic hedgehog (shh/vhh-1) mimic this effect. In contrast, expression of dermomyotomal markers can be caused by a contact-dependent signal from surface ectoderm and a diffusible signal from dorsal neural tube. Our results extend previous studies by suggesting that dorsoventral patterning of somites involves the coordinate action of multiple dorsalizing and ventralizing signals and that a diffusible form of Shh/Vhh-1 mediates sclerotome induction.  相似文献   
97.
用数学方法建立气测井油气储层识别模式,以解决录井中实时软件在判别依据少的条件下,及时识别油气显示假异常的难题。该判别式经实用,正到率达90%。  相似文献   
98.
In this report, the role of 34 kDa HA-binding protein in hyaluronic acid-induced cellular signalling in lymphocytes has been examined. The binding of 125I-HA to lymphocytes in vivo was found to be inhibited by pre-incubation of the cells with anti-34 kDa HA-binding protein antibodies, thus confirming 34 kDa HA-binding protein as the specific HA-receptor in lymphocytes. This observation was substantiated by anti-34 kDa HA-binding protein antibodies immunoblotting and 125I-HA ligand blotting of lymphocytes cell lysate. The HA-induced cell aggregation, tyrosine phosphorylation and cytoskeletal protein phosphorylation demonstrate the HA-induced early cellular signalling events in lymphocytes. Further, to study the involvement of 34 kDa HA-binding protein in mitogen induced lymphocyte signalling, we studied in vivo phosphorylation and secondary messenger formation. The enhanced 34 kDa HA-binding protein phosphorylation by HA and the inhibition of cellular aggregation and IP3 formation by anti-HA-binding protein antibodies revealed that 34 kDa HA-binding protein is one of the potential mediators in HA-induced signal transduction.  相似文献   
99.
介绍了双迭片弯曲压电陶瓷换能器的制作及边缘固定金属压电陶瓷双迭片弯曲振动,并利用有限元分析了换能器的谐振模式,采用激光多普勒干涉仪对换能器的谐振特性以及振动速度和位移分布进行了测量和分析,结果表明:换能器空载性能良好,通过有限元分析与先进测量手段的结合,能够对换能器器件的制作与分析进行指导。  相似文献   
100.
通过工程地质调查、室内围岩物化分析和力学试验 ,深入研究了围岩变形力学机制和破坏机理 .根据新奥法施工原理 ,采取了有针对性的综合治理措施 ,将围岩复杂的变形力学机制转化为单一的变形力学机制 ,使该工程得到了有效治理 .取得的技术经验推广应用于该矿井其它失稳破坏工程 ,均获得了圆满成功  相似文献   
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