碱性成纤维细胞生长因子在实验性硬脑膜重建中的应用

[目的] 探讨碱性成纤维细胞生长因子( bFGF)在实验性自体筋膜硬脑膜重建中的应用价值.[方法]取 SD大鼠 35只,分成 5组.其中 A组 3只,直接将背部筋膜覆盖在硬膜外, B组 5只,采用自体筋膜硬脑膜重建模型,通过免疫组织化学方法观察这两组大鼠自体筋膜硬脑膜移植的愈合过程及细胞因子 bFGF在其中的表达; C组、 D组、 E组各 9只,分别进行自体筋膜硬脑膜重建, D组加用外源性 bFGF, E组仅用明胶海绵,通过脑脊液漏研究、免疫组织化学方法研究外源性 bFGF对自体筋膜重建硬脑膜愈合过程的影响并用 RT- PCR方法研究内源性 bFGF mRNA的表达情况.[结果] 大鼠自体筋膜移植硬脑膜部位 bFGF表达明显; C、 D、 E组大鼠重建硬脑膜抵抗脑脊液漏压力值( mmH2O)分别为 311± 75, 497± 153, 338± 88,Ⅰ型胶原纤维表达值分别为 4.9± 0.8, 10.9± 1.6, 5.3± 0.9, D组均好于对照组( P< 0.05);内源性 bFGF mRNA的表达没有明显变化.[结论] 在自体筋膜移植硬脑膜的愈合过程中 bFGF可能起了重要的作用;外源性 bFGF处理的大鼠其移植筋膜愈合要好于对照组.     

Simulation model of renal replacement therapy: predicting future demand in England.

BACKGROUND: The demand for renal replacement therapy (RRT) in England has risen steadily, although from a lower base than many other developed countries. Predicting the future demand for RRT and the impact of factors such as the acceptance rate, transplant supply and patient survival, is required in order to inform the planning of such services. METHODS: A discrete event simulation model estimates the future demand for RRT in England in 2010 for a range of scenarios. The model uses current prevalence and current and projected future acceptance rates, survival rates and the transitions between modalities to predict future patient numbers. National population and mortality data, published literature and data from the UK Renal Registry and UK Transplant, are used to estimate unmet need for RRT, the impact of changing demography and incidence of Type 2 diabetes, patient haemodialysis (HD) survival and transplant supply. RESULTS: By 2010 the predicted prevalence will have increased from about 30,000 in 2000 to between 42 and 51,000 (900-1000 p.m.p.), an average annual growth of 4.5-6%. Changing transplant supply has a small effect on overall numbers but changes the proportion of patients with functioning graft by up to 8%. Even with an optimistic increase in transplant supply (11% p.a. for 5 years), numbers on HD will continue to rise substantially, especially in the elderly. The factors most influencing future patient numbers are the acceptance rate and dialysis survival. CONCLUSION: This model predicts a substantial growth in the RRT population to 2010 to a rate approaching 1000 p.m.p., particularly in the elderly and those on HD, with a steady state not being reached for at least 25 years.     

大鼠胰腺十二指肠移植的手术技巧

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。     

Intelligent dialogue based on statistical models of clinical decision-making

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.     

Pharmacodynamic Modeling for Change of Locomotor Activity by Methylphenidate in Rats

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 (K_i) 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.     

Modulation of cytokine production from an EpiOcular corneal cell culture model in response to Staphylococcus aureus superantigen

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     

指示肺通气不均匀性的熵变及其同其他指标的理论比较

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     

Transactional models of early education effectiveness - What is the message for policy?

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.     

Ethanol regulated preference in rats

A series of experiments evaluated the determinants of preference for mixtures of ethanol plus sucrose relative to sucrose in rats. One dipper served 10% ethanol mixed with 10% sucrose, and the second dipper served 10% sucrose. Lever presses operated each dipper according to a variable-interval 5-s schedule. In three experiments the subjects were given pre-session meals of sucrose (2.5–20 ml) or sucrose (20 ml) plus chow (5 or 10 g). Pre-session meals decreased responding maintained by sucrose but not responding maintained by ethanol mixture. In two experiments body weight was varied from 85% to 125% of the initial free-feeding values. Increases in body weight, like pre-session meals, decreased responding reinforced by sucrose, but typically did not decrease responding reinforced by ethanol mixture. Throughout most of the study, ethanol consumption remained at about 1.25 ml per half hour session (3–4 g/kg per 30 min). For example, pre-session access to ethanol mixture decreased within-session ethanol consumption, but total consumption, counting both sources, remained about 1.25 ml/session. The within-session patterns of responding also differed. Responding reinforced by ethanol mix decreased as a function of ethanol consumption, whereas responding reinforced by sucrose was relatively constant throughout the session. The simplest explanation of the results is that ethanol's pharmacological consequences regulated preference.     

实验性尘细胞灶与胸片细网状阴影形成的关系

本文从21只实验性矽肺家兔中筛选出5只胸片有细网状阴影者,用病理与 X 线对照观察的方法,探讨了实验性矽肺尘细胞灶与死后胸片细网状阴影形成的关系。证明,分布在肺细叶内直径约1mm 的尘细胞灶,其分布密度为113个/cm~2以上时,可构成胸片细网状阴影。实验排除了弥漫性肺间质纤维化的结论。并对胸片细网状阴影的形成从肺细叶解剖与 X 线投影进行了讨论。