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101.
Yue Chunfang Yin Liying 《国际中华应用心理学杂志》2005,2(3):178-181
There are the problems that influence English teaching, because the learners have the wrong understandings about the target needs and learning needs. The article analyses and discusses the teaching methods on dealing with the matter. The author thinks the teachers' adjustable function counting for much more. 相似文献
102.
目的:了解某社区常住人口恶性肿瘤平均年发病率是否高于周边人群,重点是白血病平均年发病率。方法:采用回顾性调查法及个案调查表收集该社区1998年6月~2004年9月常住人口中的确诊恶性肿瘤病人22例,将该社区恶性肿瘤平均年发病率与南山区在该时段恶性肿瘤平均的发病率进行比较。结果:1998年6月~2004年9月南山区常住人口恶性肿瘤平均年发病66.1/10万,某社区常住人口恶性肿瘤平均年发病率29.9/10万,两地差异有统计学意义(F=0.0001,P〈0.05);南山区常住人口白血病平均年发病率2.79/10万,某社区常住人口白血病平均年发病率4.07/10万,两者无统计学意义差异(F=0.467,P〉0.05)。结论:该社区常住人口恶性肿瘤及白血病平均年发病水平低于南山区全区水平。 相似文献
103.
目的:探讨上颌骨LeFortI型截骨进路切除累及翼腭凹、颞下凹巨大鼻咽纤维血管肿瘤的可行性。方法:采用矫正上颌骨先天或后天畸形的LeFortI型截骨术式进路,切除位于鼻咽部、筛窦等深在部位的纤维血管瘤。结果:该进路术野显露充分,取得了理想的治疗效果。结论:上颌骨LeFortI型截骨进路是切除鼻咽、颅底部纤维血管瘤的理想进路。 相似文献
104.
P. Boissonnat M. de Lorgeril V. Perroux P. Salen A. M. Batt J. C. Barthelemy R. Brouard E. Serres J. Delaye 《European journal of clinical pharmacology》1997,53(1):39-45
Objectives: Previous uncontrolled studies have suggested an interaction between ticlopidine, a major antiplatelet agent, and cyclosporin
in heart- and kidney-transplant recipients. The aims of this study were to examine in a randomised, double-blind fashion,
the possible interaction between cyclosporin A and ticlopidine (250 mg per day) and the tolerability of this combination in
heart-transplant recipients.
Methods: Twenty heart-transplant recipients were randomised into either a treated or a placebo group. Blood samples were drawn for
time-course evaluation of cyclosporin blood levels over a period of 12 h, following the morning intake of cyclosporin and,
for platelet aggregation studies, before and after 14 days of ticlopidine administration. Twenty four-hour urine samples were
collected for 6-β-hydroxycortisol measurements, before and after 14 days of ticlopidine.
Results: Although given at half the recommended daily dosage, ticlopidine significantly reduced platelet aggregation. Pharmacokinetic
parameters indicate that the bioavailability of cyclosporin A was not significantly modified by ticlopidine. However, one
patient in the ticlopidine group was withdrawn because of a major fall in cyclosporin blood level within 3 days of treatment.
Urinary excretion of 6-β-hydroxycortisol was augmented after treatment in the ticlopidine group compared with the placebo
group, suggesting that induction of drug metabolism might have occurred. Data also show quite a large intra-individual variability
in cyclosporin bioavailability in the placebo group, suggesting that poor absorption of the drug formulation and/or poor compliance
might have contributed to the decreased cyclosporin blood levels in the patient withdrawn from this study and in previous
uncontrolled studies.
Conclusion: Cyclosporin bioavailability was not clearly modified by a half dosage of ticlopidine in this study. We, however, recommend
closely monitoring cyclosporin blood levels when prescribing ticlopidine. Further studies will be needed with new formulations
of cyclosporin or when using the full dosage of ticlopidine.
Received: 20 July 1996 / Accepted in revised form: 12 February 1997 相似文献
105.
特异性荧光偏振免疫法监测521例肾移植后环孢素A全血浓度3275次 总被引:2,自引:0,他引:2
目的通过监测肾移植后病人环孢素A(CsA)全血浓度 ,提出CsA在三联免疫抑制用药方案中的理想治疗窗。方法用特异性荧光偏振免疫法测定CsA全血浓度 ,对521例病人监测3275次 ,按术后时间及临床表现分组比较。结果肾移植后<1 ,、1~3、3~6、6~12个月、1~2和>2年的CsA全血谷浓度的理想治疗窗应分别为250~450、200~400、150~300、100~250、100~200和100~180μg/L。结论CsA全血浓度在上述范围内 ,中毒反应和排异反应明显减少 相似文献
106.
The goal of the present study is to develop a technique for laparoscopic aortobifemoral bypass.Piglets weighing between 60 and 78 kg were anesthetized with halothane. The lateral retroperitoneal approach was preferred to the more familiar anterior transperitoneal approach and was successfully completed in 19 piglets. The piglets were placed in the right lateral decubitus position. The first port (2 cm) was inserted halfway between the tip of the 12th rib and the iliac crest. Four other trocars were placed in the retroperitoneum after balloon inflation had allowed creation of a space which permitted visualization of the aorta from the left renal artery down to the aorto-iliac junction. After evacuation of the retropneumoperitoneum, the cavity was maintained using an abdominal lift device and a retractor.Using this approach, we performed four aortobifemoral bypasses (end-to-end aortic anastomosis) after conventional intravenous heparinization (100 IU/kg) in less than 4 h. Blood loss did not exceed 250 ml and the hematocrit remained stable. Postmortem evaluation of the grafts revealed they were positioned as in a conventional bypass, their limbs having followed in the created retroperitoneal tunnels along the path of the native arteries. No mortality occurred before sacrifice of the animals. We believe that this first performed series of totally retroperitoneal laparoscopic aortobifemoral bypasses in the porcine model is useful in preparation for human application due to the anatomical similarities in the periaortic region. 相似文献
107.
David S. Park Paul Manowitz Stanley Stein Ronald D. Poretz 《Alcoholism, clinical and experimental research》1996,20(2):234-239
Several electrophoretic forms of human platelet arylsulfatase A (ASA), including variant type IIIa and normal type IVa , have been identified by nondenaturing polyacrylamide gel electrophoresis. An alcoholic population that we have analyzed is enriched in variant type IIIa compared with nonalcoholic psychiatric and normal controls. Individuals with the IIIa enzyme possess greatly reduced levels of ASA activity. To understand further the structural basis for the differences and their potential biological consequences, the nature of the ASA variant expressed by fibroblasts from different individuals was explored. The electrophoretic patterns of fibroblast ASA from the IIIa and IVa individuals differ in degree of phosphorylation. Furthermore, fibroblast ASA from IIIa individuals lacks an N -linked glycan found in ASA from IVa individuals. In addition, differences in peptide and/or posttranslational modification unrelated to the N -linked carbohydrate or phosphorylation exist between the fibroblast ASA from IIIa and IVa individuals. The finding that both fibroblasts and platelets exhibit related electrophoretic isoform patterns characteristic of the donor's ASA type allows for the use of fibroblasts to study the impact of ethanol on the metabolism of cells possessing different ASA types. 相似文献
108.
应用标准微电极技术,研究了关附甲素对豚鼠右心室乳头肌动作电位最大除极速率(Vmax)的频率依赖性抑制作用(RDB),并与美西律,奎尼丁,劳卡尼进行了比较. 在相同刺激间隔(300 ms),产生50%左右RDB的药物浓度下,美西律的RDB开始最快,其第2个Vmax所产生的抑制已占RDB的64%,奎尼丁,劳卡尼和关附甲素的RDB开始速率常数分别为每个动作电位0.165, 0.076和0.136. 美西律,奎尼丁,劳卡尼和关附甲素产生RDB的恢复时间常数分别为1.4, 9.0, 18.2和44.0 s,而且它们的恢复时间常数是不依赖于药物浓度而变化的,结果提示,关附甲素是一个慢动力学钠通道阻滞剂. 相似文献
109.
Characterization of the human cytochrome P450 enzymes involved in the metabolism of dihydrocodeine 总被引:1,自引:0,他引:1
L. C. Kirkwood R. L. Nation & A. A. Somogyi 《British journal of clinical pharmacology》1997,44(6):549-555
Aims Using human liver microsomes from donors of the CYP2D6 poor and extensive metabolizer genotypes, the role of individual cytochromes P-450 in the oxidative metabolism of dihydrocodeine was investigated.
Methods The kinetics of formation of N- and O -demethylated metabolites, nordihydrocodeine and dihydromorphine, were determined using microsomes from six extensive and one poor metabolizer and the effects of chemical inhibitors selective for individual P-450 enzymes of the 1A, 2A, 2C, 2D, 2E and 3A families and of LKM1 (anti-CYP2D6) antibodies were studied.
Results Nordihydrocodeine was the major metabolite in both poor and extensive metabolizers. Kinetic constants for N -demethylation derived from the single enzyme Michaelis-Menten model did not differ between the two groups. Troleandomycin and erythromycin selectively inhibited N -demethylation in both extensive and poor metabolizers. The CYP3A inducer, α-naphthoflavone, increased N -demethylation rates. The kinetics of formation of dihydromorphine in both groups were best described by a single enzyme Michaelis-Menten model although inhibition studies in extensive metabolizers suggested involvement of two enzymes with similar K m values. The kinetic constants for O -demethylation were significantly different in extensive and poor metabolizers. The extensive metabolizers had a mean intrinsic clearance to dihydromorphine more than ten times greater than the poor metabolizer. The CYP2D6 chemical inhibitors, quinidine and quinine, and LKM1 antibodies inhibited O -demethylation in extensive metabolizers; no effect was observed in microsomes from a poor metabolizer.
Conclusions CYP2D6 is the major enzyme mediating O -demethylation of dihydrocodeine to dihydromorphine. In contrast, nordihydrocodeine formation is predominantly catalysed by CYP3A. 相似文献
Methods The kinetics of formation of N- and O -demethylated metabolites, nordihydrocodeine and dihydromorphine, were determined using microsomes from six extensive and one poor metabolizer and the effects of chemical inhibitors selective for individual P-450 enzymes of the 1A, 2A, 2C, 2D, 2E and 3A families and of LKM1 (anti-CYP2D6) antibodies were studied.
Results Nordihydrocodeine was the major metabolite in both poor and extensive metabolizers. Kinetic constants for N -demethylation derived from the single enzyme Michaelis-Menten model did not differ between the two groups. Troleandomycin and erythromycin selectively inhibited N -demethylation in both extensive and poor metabolizers. The CYP3A inducer, α-naphthoflavone, increased N -demethylation rates. The kinetics of formation of dihydromorphine in both groups were best described by a single enzyme Michaelis-Menten model although inhibition studies in extensive metabolizers suggested involvement of two enzymes with similar K
Conclusions CYP2D6 is the major enzyme mediating O -demethylation of dihydrocodeine to dihydromorphine. In contrast, nordihydrocodeine formation is predominantly catalysed by CYP3A. 相似文献
110.
The effect of Cyclosporin A (CsA) on prostaglandin E2 (PGE2 ) production in human gingival fibroblasts challenged with tumor necrosis factor alpha (TNF-α) was studied. TNF-α (1-100 ng/ml) dose-dependently stimulated PGE2 ; formation in 24 h cultures. CsA (1-100 ng/ml) did not induce PGE2 ; formation itself but potentiated TNF-α induced PGE; formation in gingival fibroblasts in a manner dependent on the concentrations of both CsA and TNF-α. TNF-α (10 ng/ml) stimulated the release of [3 H]-arachidonic acid (A.A) from prelabelled fibroblasts that was potentiated by CsA (100 ng/ml). Addition of exogenous unlabelled AA (5-20 μM/ml) to the cells resulted in enhanced PGE2 : formation that was not potentiated by CsA (100 ng/mi). Furthermore. CsA (100 ng/ml) did not further increase the level of cyclooxygenase-2 mRNA induced by TNF-α (10 ng/ml). although PGE2 formation was enhanced. The results indicate that CsA and TNF-α act in concert on PGE2 formation in gingival fibroblasts. which may be of importance in the pathogenesis of gingival overgrowth induced by the drug. 相似文献