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91.
大鼠胰腺十二指肠移植的手术技巧   总被引:1,自引:0,他引:1  
目的探讨建立大鼠胰腺十二指肠移植模型的手术技巧。方法不阻断体循环,采用双套管将供胰所带腹主动脉、门静脉分别与受鼠的左肾动、静脉进行套管吻合,尽量减轻对全身血流动力学的影响;同时行十二指肠空肠端侧吻合引流胰液,重建胰腺外分泌途径;围手术期注意补液、保暖及抗凝。结果100例手术中83例手术成功,术后移植胰腺具有内分泌功能,胰腺轻度充血水肿。结论该移植模型不阻断体循环且操作简单实用,其成功的关键在于手术操作及围手术期处理。  相似文献   
92.
PROBLEM: To compare depressive symptoms in children with attention deficit hyperactivity disorder (ADHD) to those in healthy children, and to explore the influence of individual and family factors on level of depression. METHODS: Individual interviews with 68 children, ages 7 to 12 years, in order to complete the Children's Depression Inventory. FINDINGS: Children with ADHD reported significantly more depressive symptoms than did children without ADHD; 14.7% of children with ADHD reached the threshold of a 19 point score, which suggests clinical depression. No significant effects of individual and family factors on level of depression were found. CONCLUSIONS: Children with ADHD are more inclined to experience depressive symptoms than are healthy children. To plan appropriate interventions, nurses evaluating and working with children with ADHD should always consider a possible coexistence of depressive symptoms.  相似文献   
93.
立体着床模型--小鼠囊胚与子宫内膜的共培养   总被引:1,自引:0,他引:1  
谭冬梅  谭毅  赵劼  艾玲  王智彪 《医学争鸣》2005,26(15):1359-1362
目的:建立小鼠囊胚体外着床的三维模型,为着床机制的研究提供重要工具.方法:将小鼠囊胚与其自身子宫内膜分别共培养在空气、含500,750和950 mL/L O2的混合气体与组织培养液的气液界面上,比较不同O2浓度下小鼠囊胚的贴附率,确定体外共培养的最佳O2浓度;同时将确认有囊胚贴附的子宫内膜取出作HE染色.结果:不同O2浓度下,囊胚的贴附率分别为64.75%,47.86%,42.37%和30.97%,x2检验提示其差异有显著性(x2=28.145,P=0.000);且随着混合气体中O2浓度的逐渐升高,囊胚贴附率呈逐渐降低趋势.因此50 mL/L CO2 950 mL/L空气对囊胚与子宫内膜的共培养是最有利的;同时,囊胚贴附子宫内膜后并无扩展行为而是直接侵入子宫内膜.结论:50 mL/L CO2 950 mL/L空气最有利于囊胚与子宫内膜的共培养;且囊胚贴附子宫内膜后不发生外延生长,而是直接侵入子宫内膜.本实验成功地建立了小鼠囊胚体外着床的三维模型.  相似文献   
94.
The independence Bayesian model has been used widely in computer programs designed to support clinical decision-making. A reasoning strategy has been developed to enable these programs to conduct clinically pertinent dialogue and explain their reasoning. It has been implemented in a program for the diagnosis of acute abdominal pain based on the Bayesian model of de Dombal et al. Several features of the dialogue design have been adopted from artificial intelligence research, including shared initiative and critiquing. The program adopts a flexible goal-driven strategy, attempting to confirm the clinician's diagnosis or rule out the likeliest alternative. Symptoms and signs are selected in order of their expected weights of evidence in favour of the hypothesized disease.  相似文献   
95.
Purpose. The locomotive activity changes after intravenous (i.v.) administration of methylphenidate (MPD) in rats were pharmacodynamically analyzed. Methods. MPD concentration in plasma, MPD concentration and dopamine (DA) level in striatal dialysate collected by microdialysis method, and the locomotor activity after i.v. administration of MPD (2, 5 and 10 mg/kg doses) were used for the analysis. Results. The transport of MPD from plasma to the interstitial fluid in the brain could be expressed by the linear two-compartment model. The clockwise hysteresis between the MPD concentration and the DA level in the dialysate could be explained by the pharmacodynamic model considering Michaelis-Menten type reuptake process of the extracellular DA into the terminal of the dopaminergic nerve and its competitive inhibition by the extracellular MPD. The inhibition constant (Ki) of MPD for DA reuptake was estimated to be 41.3 ± 73.8 nM (mean ± SE), which was closely consistent with the in vitro value after correction with dialysis recovery. The relationship between DA level in dialysate and locomotor activity was expressed by the Emax model considering two contrary effects, hyperkinesia and stereotypy. The bi-phasic locomotor activity-time profiles after high dose of MPD could be represented by this model. Conclusions. The developed model made it possible to explain the tolerance in DA increase and the complicated locomotive change induced by MPD, and may be useful for other DA reuptake inhibitors, such as amphetamine and methamphetamine.  相似文献   
96.
The present study investigated the hypothesis that Staphylococcus aureus enterotoxin B (SEE) produces epithelial cell death and releases inflammatory cytokines that produce stromal infiltration during contact lens induced peripheral ulceration. Epithelial cells were incubated with different doses of SEB for various time periods. Culture supernatants were assayed for cytokines IL- lo, IL-6 and chemotactic agents IL-8 and LTB,. SEE induced the production of IL- I p and IL-8. Epithelial cells exposed for longer periods (48 h) with low concentrations of SEB produced significantly higher levels (N0.02) of IL-Ip and IL-8 (P<0.05) compared t o a 24 h exposure. SEB did not induce the production o f IL-6 and  相似文献   
97.
The systolic hump in the aortic blood pressure wave is defined as the aorticresistance component proportional to the aortic blood flow superimposed on the windkessel component. An electrical analogue comprising a series resistance (aortic resistance) plus a resistance (peripheral resistance) and capacitance (aortic compliance) in parallel (i.e. windkessel component) is used for analysis. Curve fitting using the leastsquares method is performed on calculated and measured blood pressure waves from dogs under haemodynamical conditions induced by infusion of three drugs (noradrenaline, isoproterenol and acetylcholine). The curve fitting RMS (root mean square) errors are <3% for blood pressure waves and <30% for blood flow waves, with good agreement between measured and calculated blood flow waveforms. Infusion of noradrenaline and acetylcholine is found to induce a significant decrease and increase in the aortic resistance, respectively. Although only a small fraction of the blood pressure wave, the systolic hump has a marked effect on the systolic pressure waveform.  相似文献   
98.
This paper presents a statistical model constructed using logisticregression to identify those at high-risk of repeating parasuicide. Thesubjects in the study are Cork city residents who exhibited parasuicidalbehaviour between 1 January and 30 June 1995. Repetition of the behaviourwithin six months of the index episode distinguishes repeaters fromnon-repeaters. The model was designed so that it could be used bynon-clinicians and hence does not require information relating topsychiatric diagnosis or use of psychiatric services. The proportion ofsubjects correctly classified remained stable across a range of cut-pointprobabilities (mean = 86%, range: 83.9–87.5%). Using acut-point of 0.2, 96% of repeaters and 81% of non-repeaters were correctly classified. Using 0.45 led to the correct identification of81% of repeaters and 90% of non-repeaters. If these highlevels of sensitivity and specificity are maintained in validation tests onfuture cohorts in Cork city then the model could form the basis of anintervention programme designed to prevent the repetition of parasuicide.  相似文献   
99.
熵代表无序的水平,作者使用通气的熵变(ECV)指示肺通气的不均匀性,ECV定义为当前泡潮气量趋近于零时每摩尔被吸入气体从不均匀通气到均匀通气的熵变的极限。本文从熵的基本公式民地出ECV的计算方程。用几个数学模型肺将ECV同其他7个洗出指标进行了比较。8个指标中,只有ECV仅取决于通气分布,其他7个指标不仅取决于通气分布,还同潮气量和死腔的大小有关。这影响了它们评价肺通气不均匀性的效果,ECV的另一  相似文献   
100.
There is now a substantial body of American research evidence demonstrating that early education programmes can have major long term effects right through into adult life. Cost-benefit analysis has enabled the data to be transformed into a compelling case for public financial investment. But insufficient attention has been paid to explaining how a short term preschool programme could have such enduring effects. The effects are best understood by applying a transactional model which shows how processes in the school and community transformed and amplified short term effects into long term outcomes. Adopting a transactional model modifies the messages for policy. The results of evaluations carried out in one society may not apply in another. In some school systems there may be more effective strategies than early education for improving educational prospects.  相似文献   
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