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991.
A rapid nonsterile short-term assay has been investigated in which percent inhibition of incorporation of the DNA precursor (3H)-thymidine is measured following exposure of tumor cells to the test drugs. To evaluate the usefulness of the short-term assay in providing a rapid reliable assessment of chemotherapeutic response, the short-term assay was compared with the soft agar clonogenic assay. Sensitivity to five anticancer drugs was compared using three human tumor cell lines (epidermoid carcinoma of the oral cavity, pancreatic carcinoma, and bladder carcinoma). The short-term assay produced results that were similar to results of the clonogenic assay in two of the three tumors tested, for three drugs (cis-platin, doxorubicin, and BCNU), but did not detect responses to two antimetabolites (5-FU and MTX) in any tumor. Further studies of this short-term assay should focus on alkylating agents and other nonantimetabolites. 相似文献
992.
S. D. ROBINSON† C. A. LUDLAM‡ N. A. BOON† D. E. NEWBY† 《Journal of thrombosis and haemostasis》2006,4(10):2262-2269
OBJECTIVES: To determine if polymorphisms of the tissue plasminogen activator (t-PA) gene influence acute endogenous t-PA release in patients with coronary heart disease (CHD). METHODS: Forearm blood flow and plasma t-PA concentrations were measured in response to intra-brachial infusion of substance P and sodium nitroprusside in 96 patients with stable CHD. Genotyping was performed using a Taqman polymerase chain reaction assay specifically designed to detect the polymorphisms of interest: (i) Alu-repeat insertion/deletion sequence; (ii) C-->T substitution in an upstream enhancer region (-7351 C/T); (iii) T-->C in exon 6 (20 099 T/C); and (iv) T-->A (27 445 T/A) in intron 10. RESULTS: Substance P and sodium nitroprusside caused dose-dependent increases in forearm blood flow in all patients (P < 0.001 for all) that were independent of the four genetic polymorphisms. Similarly, there were no differences in basal plasma t-PA antigen concentrations or net t-PA release between genotypes. Compared to non-smokers, smokers exhibited impaired substance P-induced vasodilatation (P < 0.001) and t-PA release (P = 0.05). CONCLUSIONS: Despite confirming our previous findings in cigarette smokers, we have found no effect of polymorphisms of the t-PA gene on two complementary aspects of endothelial function. We conclude that genetic variation of the t-PA locus is unlikely to have a major influence on acute t-PA release in subjects with established CHD. 相似文献
993.
本文通过复习大量文献资料,阐述了电子束CT的原理及钙化评分方法,全面分析了电子束CT对冠心病的诊断价值、对冠心病预后的评价意义及对冠心病病情进展和治疗效果的监测意义等。总之,电子束CT可用于冠心病的诊断和评价。 相似文献
994.
目的探讨自发性高血压大鼠颈动脉中抑癌基因P53和原癌基因c-jun、c-fos、c-myc mRNA的表达.方法用逆转录聚合酶链式反应检测两种基因的表达水平.正常雄性大鼠作为对照组.结果 SHR颈动脉中,抑癌基因P53和原癌基因c-jun、c-fos、c-myc均有高表达,较WKY差异有显著性(P<0.05).结论自发性高血压大鼠颈动脉组织中抑癌基因P53和原癌基因c-jun、c-fos、c-myc均有高表达,癌基因的活化可能与自发性高血压大鼠颈动脉血管重构有关. 相似文献
995.
目的:探讨细胞活素肿瘤坏死因子-α(TNF-α)、SNAP(S-Nitroso-Nacetyl-penicillamine)对胰腺癌细胞产生血管内皮生长因子A、C(VEGF-A、C)的调节.方法:用Northern杂交和Western杂交法分析6种人胰腺癌细胞株中VEGF-A、C基因和蛋白的表达;以TNF-α或SNAP刺激其中两个细胞株后用逆转录-聚合酶链式反应技术(RT-PCR)分析其VEGF-A、C基因的表达.结果:Northern杂交法显示这6种胰腺癌细胞株均有4.1kb VEGF-A基因和2.4kb VEGF-C基因的表达;Western杂交法显示它们均有分子量为43kD的VEGF-A蛋白质和分子量为55kD的VEGF-C蛋白质的表达.RT-PCR分析法显示:TNF-α使细胞株COLO-357产生VEGF-A、VEGF-C mRNA分别减少约1~2.5倍、1~2倍,使细胞株CAPAN-1产生VEGF-A、VEGF-C mRNA分别减少约1倍、1.6~2.5倍;而SNAP刺激细胞株COLO-357产生VEGF-A mRNA增加约5倍,刺激细胞株CAPAN-1产生VEGF-A mRNA增加约4倍,但对这两种细胞株产生VEGF-C mRNA均无明显刺激作用.结论:细胞活素TNF-α和低氧通过调节血管内皮生长因子A、C的表达而影响胰腺癌细胞的生物学特性,抑制癌细胞的增殖,促进其凋亡、死亡或进展、恶化. 相似文献
996.
P. Subashini Dr. A. Ravikumar M.S. DNB DLORCS M. S. Ranjit V. K. Sairam R. P. Vatsanath S. Jayasree 《Indian journal of otolaryngology and head and neck surgery》2007,59(1):73-75
A two and half year old male child was seen with systemic hypertension, left ventricular dysfunction, mitral regurgitation and congestive cardiac failure. Examination revealed adenoid hypertrophy. He was also suffering from obstructive sleep apnea. He was being treated with anti-hypertensive and anti-failure drugs. Adenoidectomy was performed following which obstructive sleep apnea symptoms disappeared and his cardiac status improved markedly. Subsequently he was weaned off anti-hypertensive and anti-failure therapy. 相似文献
997.
腹腔热灌注化疗在卵巢癌术后的应用探讨 总被引:1,自引:1,他引:0
目的:探讨卵巢癌术后腹腔热灌注化疗的可行性、安全性及短期疗效。方法:对2002年7月至2005年12月收治的25例卵巢癌,术中均行根治或姑息性切除;对直径≥0.5cm的腹腔内转移灶用电刀减量戮灭。术后第1d开始,每日腹腔热灌注化疗1次,每次60-90min,一般4次为1疗程,共计做98次。结果:循环通畅率96.9%(62/64),治疗时间内腹腔内温度82%达到41℃以上,各出水管温度均超过41℃,并保持60~90min。并发症及毒副反应有:轻度腹腔感染2例,腹痛4例,恶心呕吐2例,转氨酶轻度升高1例。随访6~27个月,术后每3个月复查1次B超或CT,腹腔转移3例,腹腔转移率为18.8%,1例术后6个月死于全身广泛转移,另1例术后13个月死于腹腔转移及肝转移。最长1例随访时间为29个月,现仍存活。结论:术后早期腹腔热灌注化疗安全,腹腔内温度较均匀,可多次进行,并发症少且毒副反应小,有利于卵巢癌术后腹腔内较小的残余癌或游离癌细胞的杀灭。 相似文献
998.
Measuring staff perceptions of challenging behaviour: the Challenging Behaviour Attributions Scale (CHABA) 总被引:1,自引:1,他引:0
R. P. Hastings 《Journal of intellectual disability research : JIDR》1997,41(6):495-501
Causal attributions may interact with other variables to determine staff responses to challenging behaviour. Furthermore, staff perceptions of the causes of challenging behaviour are likely to change as a result of theoretical and practical training. However, there is no established simple method for measuring staff attributions that could facilitate research in these areas. The present paper describes the development and preliminary psychometric analysis of the Challenging Behaviour Attributions Scale (CHABA). 相似文献
999.
1000.
H. Isoniemi J. Ahonen B. Eklund K. Höckerstedt K. Salmela E. von Willebrand P. Häyry 《Transplant international》1990,3(2):92-97
We have investigated the impact of triple drug immunosuppression on the occurrence of early inflammatory episodes, as detected by fine needle aspiration biopsy, and of episodes of clinical rejection during the immediate postoperative period. The prospective component of this study includes 128 consecutive first cadaveric renal transplant recipients receiving triple drug treatment consisting of azathioprine (Aza), cyclosporin (CyA) and methylprednisolone (MP). For controls we have used three historical groups: one immunosuppressed with Aza and MP (group A), another with CyA monotherapy (group B), and the third with CyA together with MP (group C) in equivalent drug dosages. On the average, 0.8 episodes of inflammation per patient were recorded during the immediate postoperative period of 30 days with triple drug treatment. This was significantly less than the 1.3 episodes in patients receiving Aza and MP (P<0.01), the 1.7 episodes in patients on CyA monotherapy (P<0.001), or the 1.6 episodes in patients receiving CyA together with MP (P<0.001). Although the first episode of inflammation commenced concurrently in each group and the peak intensity of inflammation was the same, the mean duration of inflammation was significantly shorter-2.7 days-under triple drug treatment than the 7.8–11.7 days for controls (P<0.001). The frequency of rejection episodes under triple treatment was also significantly lower-0.2 per patient-than the 0.8 per patient in controls (P<0.001). The first rejection episode occurred later in the triple drug treatment group-on the average, on day 15.2-than in the historical controls (on days 7.7–11.7). There was, however, no difference in the duration of rejection. There were no differences in patient survival between the four groups. Graft survival was 97% at 10 weeks for triple drug-treated recipients and 79%, 68%, and 87% for first grafts in groups A, B, and C, respectively. Disregarding a minor demographic bias for the triple drugtreated group with respect to preformed antibodies and preoperative dialysis treatment, the study suggests that the triple drug protocol, in the short run, is superior to any conceivable double drug combination or CyA monotherapy. 相似文献