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91.
用Harris冠脉结扎法诱发的心律失常狗研究常咯啉药代动力学-药效动力学。7只狗按83.33μg·kg ̄(-1)·min ̄(-1)静脉滴注60min,在给药期间和停药后不同时间记录ECG及测定血药浓度。C-T数据用药代程序计算药代参数;药效数据用药代-药效同步分析模型计算药效动力学参数,K10,T1/2,Vd,Cl分别为0.0087min ̄(-1),78.03min,40.55ml·kg ̄(-1)和0.421ml·kg ̄(-1)·min ̄(-1);Ke0和Ce(50)分别为0.0048min ̄(-1)和2.01μg·ml ̄(-1).  相似文献   
92.
王玉  陈国良  吴耀民 《医学争鸣》2005,26(10):960-960
在大规模登陆作战中需要大量的卫生船舶实施各种保障,因此必须对卫生船舶进行合理的配置,保证其既能有效地完成保障任务,又能避免重叠配置造成浪费.卫生船舶的配置应与指挥关系、保障任务战时分类相适应,具体配置时按医院船、卫生运输船、卫生救护艇的保障要求配置,并可根据保障任务的变化进行相应的调整.  相似文献   
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94.
The purpose of this study was to determine the molecular basis for a relative deficiency in the cat of cytosolic arylamine N-acetyltransferase (NAT), an enzyme family that is important in the metabolism of xenobiotics and that normally consists of at least two related enzymes, NAT1 and NAT2. N-acetyltransferase in feline liver showed high affinity (mean Km = 2.1 microM) for p-aminobenzoic acid, an NAT1 selective substrate in humans and rabbits, but showed a very poor affinity (mean Km > 10 mM) for sulfamethazine, an NAT2 selective substrate in humans and rabbits. Immunoreactive N-acetyltransferase was detected in feline liver, bladder and colon using an NAT1-specific antipeptide antibody, but was not detected in any tissues using an NAT2-specific antibody. Southern blot analysis of genomic DNA demonstrated a single band in domestic cats using each of six restriction digests; single bands were also found on Southern blot analysis of six wild felids. The deduced amino acid sequence of the central portion of feline N-acetyltransferase, obtained by polymerase chain reaction amplification in both domestic cats and seven wild felids (lion, tiger, lynx, snow leopard, bobcat, Asian leopard cat and cheetah), contained three residues, Phe125, Arg127, and Tyr129, which determine NAT1-like substrate specificity in humans. These results support the conclusion that cytosolic arylamine N-acetylation activity is low in the cat because of the presence of a single N-acetyltransferase that has substrate specificity, immunogenicity and sequence characteristics similar to human NAT1, and that the unusual presence of only a single N-acetyltransferase gene appears to be a family wide trait shared by other felids.  相似文献   
95.
BMP2,3,4,5 mRNA在三叉神经中的表达分析   总被引:1,自引:0,他引:1  
目的:明确 B M Ps 与外周神经的关系。方法:用原位杂交方法观察 B M P2,3,4,5 的m R N A在三叉神经中的表达。结果:在外周神经(三叉神经)中均有 B M P2,3,4,5 m R N A 分布, B M P2,3,4,5 的分布主要位于构成神经纤维髓鞘的雪旺细胞中;此外发现 B M P2 在部分神经纤维中也有表达。结论:首次确定了 B M P2,3,4,5 在外周神经中的表达和分布,揭示了 B M P2,3,4,5可能在外周神经的发育和再生以及形态结构的维持中发挥着调控作用。  相似文献   
96.
OBJECTIVES: Ameloblastomas appear to exhibit biological heterogeneity and, except in the case of malignancy, histological appearances that do not always allow their behaviour to be predicted. The aim of this study was to assess keratin expression in African ameloblastomas and to correlate this with their clinical and histological features. MATERIALS AND METHODS: Expression of simple keratins 7, 8, 18 and 19; cornification keratins 1 and 10; basal and differentiation keratins 5 and 14 and hyperproliferation-related keratins 6 and 16 in 14-39 cases of ameloblastoma was assessed by immunohistochemical methods. RESULTS: There was patchy expression of keratin 7 in the suprabasal and stellate reticulum-like cells in some cases. All cases showed similar weak expression for keratins 8 and 18 in suprabasal and stellate reticulum-like cells but none showed keratin 1 or 10 expression. There was intense expression of keratins 5, 14 and 19 by all tumour cells suggesting that they may retain basal cell characteristics with a potential for proliferation. No consistent relationship was seen between histological types and keratin expression pattern. However, keratins 6 and 16, expressed by suprabasal and stellate reticulum-like cells, showed a marked variation within and between cases, with the highest levels of expression in squamous strands. CONCLUSIONS: We propose that squamous strands may represent the sites of most active growth within individual tumours and expression of keratins 6, 16 and 19 may be predictors of rapid growth. There is a need for further investigation of this in longitudinal clinical studies.  相似文献   
97.
GL Reed  AK Houng 《Circulation》1999,99(2):299-304
BACKGROUND: The resistance of thrombi to fibrinolysis induced by plasminogen activators remains a major impediment to the successful treatment of thrombotic diseases. This study examines the contribution of activated factor XIII (factor XIIIa) to fibrinolytic resistance in experimental pulmonary embolism. METHODS AND RESULTS: The fibrinolytic effects of specific inhibitors of factor XIIIa-mediated fibrin-fibrin cross-linking and alpha2-antiplasmin-fibrin cross-linking were measured in anesthetized ferrets with pulmonary emboli. Five experimental groups were treated with heparin (100 U/kg) and/or tissue plasminogen activator (TPA, 1 mg/kg) and the percent (mean+/-SD) lysis of emboli was determined: (1) control, normal factor XIIIa activity (14.1+/-4. 8% lysis); (2) inhibited factor XIIIa activity (42.7+/-7.4%); (3) normal factor XIIIa activity+TPA (32.3+/-7.7%); (4) inhibited factor XIIIa activity+TPA (76.0+/-11.9%); and (5) inhibited alpha2-antiplasmin-fibrin cross-linking+TPA (54.7+/-3.9%). Inhibition of factor XIIIa activity increased endogenous lysis markedly (group 1 versus 2; P<0.0001), to a level comparable to that achieved with TPA (group 2 versus 3; P<0.05). Among groups receiving TPA, selective inhibition of factor XIII-mediated alpha2-antiplasmin-fibrin cross-linking enhanced lysis (group 3 versus 5; P<0.0005). Complete inhibition of factor XIIIa also amplified lysis (group 3 versus 4; P<0.0001) and had greater effects than inhibition of alpha2-antiplasmin cross-linking alone (group 4 versus 5; P<0.0005). No significant fibrinogen degradation occurred in any group. CONCLUSIONS: Factor XIIIa-mediated fibrin-fibrin and alpha2-antiplasmin-fibrin cross-linking both caused experimental pulmonary emboli to resist endogenous and TPA-induced fibrinolysis. This suggests that factor XIIIa may play a critical role in regulating fibrinolysis in human thrombosis.  相似文献   
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99.
AIM:The present study was undertaken to isolate and standardize the various active phytochemical constituents present in the fruit rinds of Punica granatum.METHODS:Fruit rinds of Punica granatum were dried and extracted with methanol in a static extractor;the percentage yield of the methanolic extract (MEPG) was found to be 26%;the methanolic extract was partitioned using n-butanol,ethyl acetate and water;the percentage yield of the fractions were found to be 17.16%,26.88% and 47.72% respectively.HPLC was c...  相似文献   
100.
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