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41.
后循环缺血性事件患者预后的临床分析   总被引:2,自引:0,他引:2  
鞠奕  王桂红  王拥军 《北京医学》2006,28(11):647-649
目的 评估206例后循环缺血性事件患者30d预后,探讨不同病变部位及受累血管与30d预后不良的相关性.方法 收集206例后循环急性脑梗死和短暂性脑缺血发作患者的临床资料.全部患者均在入院时进行美国国立卫生院神经功能缺损量表(NIHSS)、改良Rankin残障量表(MRS)评估,病后30d进行MRS评估,分析患者30d预后;系统评价病变部位及受累血管,并与预后不良进行相关性分析.结果 本组206例,病后30d病死率为4.9%,致残率为18%,颅脑近中远段同时受累(r=9.270,P<0.001)、基底动脉急性闭塞(r=5.106,P<0.001)及颅内病变个数>1个(r=2.491,P<0.001)的患者预后不良.结论 不同病变部位、血管引起的后循环缺血性事件预后不同,大部分预后良好.  相似文献   
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Diethylstilbestrol (DES), a non‐steroidal estrogen, has been found to cause altered germ cell development and disordered ovarian development in fish females. However, the mechanisms that might be involved are poorly understood. In this study, female juveniles of yellow catfish (Pelteobagrus fulvidraco) (120 days post‐hatching) were exposed to two doses (10 and 100 ng l?1) of DES for 28 days. After the endpoint of exposure, decreased ovary weight and gonadosomatic index, as well as various ovarian impairments were observed in response to DES. Besides, DES elevated the mRNA levels of vitellogenin 1 (vtg 1) and estrogen receptor 1 (esr 1) in liver and decreased 17β‐estradiol level in plasma. Correspondingly, suppressed mRNA levels of the key genes in the hypothalamic–pituitary–gonadal axis (such as cyp19a1b, gnrh‐II, fshβ and lhβ in brain and fshr, lhr and cyp19a1a in ovary) after DES exposure were also observed. The declined level of plasma 17β‐estradiol and altered gene expressions of genes in the hypothalamic–pituitary–gonadal axis were thus supposed to be closely related to the disrupted oogenesis in DES‐treated fish. Analyses further demonstrated that, higher concentration of DES elevated the expression ratio of bax/bcl‐2, indicating the enhanced apoptosis occurred in ovary. Moreover, DES upregulated the expressions of genes involved in proliferation (cyclin d1 and pcna), meiotic entry (cyp26a1 and scp3) and meiotic maintenance (dmc1), resulting in arrested oogenesis in catfish. The present study greatly extended our understanding on the mechanisms underlying of reproductive toxicity of DES on fish oogenesis.  相似文献   
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An accurate dosage determination is required in neonates when antibiotics are used. The adult data cannot be simply extrapolated to the pediatric population due to significant individual differences. We aimed to identify factors impacting ceftazidime exposure in neonates and to provide drug dosing guidance to clinicians. Forty-three neonates aged less than 60 days with proven or suspected infections were enrolled in this study. After intravenous administration, blood samples were collected, and plasma ceftazidime concentration was determined using a HPLC method. Pharmacokinetic data were fitted using a nonlinear mixed-effects model approach. One-compartmental model could nicely characterize the ceftazidime in vivo behavior. The covariate test found that the postmenstrual age (day) was strongly associated with systemic drug clearance (L/h), and the effect of body weight (kg) was identified as the covariate on distribution volume (L). Compared with the base model, the addition of covariates improved the goodness-of-fit of the final model. Model validation (bootstrap, visual predictive check, and prediction-corrected visual predictive check) suggested a robust and reliable pharmacokinetic model was developed. Personalized dosage regimens were provided based on model simulations. The intravenous dose should be adjusted according to postmenstrual age, body weight, and minimum inhibitory concentration.  相似文献   
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Needle-free injection (NFI), as an alternative drug delivery strategy, owns great potential. It is able to reduce complaints about needle phobia and avoid the occurring of accidental needle stick injuries. The nozzle diameter is inherently important in determining the injection dose, injection depth, and pain associated with NFIs. In this work, needle-free injectors with nozzle diameters of 0.17, 0.20, 0.30, 0.40, and 0.50 mm were studied in the simulation and experiment. This article optimizes the mathematical model for spring-powered NFI by considering the hydraulic loss due to the abrupt change in the nozzle exit area and the friction force between the piston and ampoule. We explore the dispersion pattern in gels with different nozzle diameters. Mice insulin injection was conducted to investigate the pharmacological effect of different injection methods. The experimental results show that there is the best dispersion effect and available injection depth while the nozzle diameter is 0.30 mm, which is in agreement with the result predicted by the mathematical model. Also, there is a satisfactory pharmacological effect on the mice insulin injection under the same injection condition. Undoubtedly, the mathematical model is capable of predicting the suitable nozzle diameter under the given conditions.  相似文献   
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The objectives of this study were to explore sodium dodecyl sulfate (SDS) and Soluplus on the crystallization inhibition and dissolution of felodipine (FLDP) extrudates by bottom-up and top-down approaches. FLDP extrudates with Soluplus and SDS were prepared by hot melt extrusion, and characterized by polarized light microscopy, differential scanning calorimetry, and fourier transform infrared spectroscopy. Results indicated that Soluplus inhibited FLDP crystallization, and the whole amorphous solid dispersions (ASDs) were binary FLDP-Soluplus (1:3) and ternary FLDP-Soluplus-SDS (1:2:0.15~0.3 and 1:3:0.2~0.4) extrudates. Internal SDS (5%-10%) decreased glass transition temperatures of FLDP-Soluplus-SDS ternary ASDs without presenting molecular interactions with FLDP or Soluplus. The enhanced dissolution rate of binary or ternary Soluplus-rich ASDs in the nonsink condition of 0.05% SDS was achieved. Bottom-up approach indicated that Soluplus was a much stronger crystal inhibitor to the supersaturated FLDP in solutions than SDS. Top-down approach demonstrated that SDS enhanced the dissolution of Soluplus-rich ASDs via wettability and complexation with Soluplus to accelerate the medium uptake and erosion kinetics of extrudates, but induced FLDP recrystallization and resulted in incomplete dissolution of FLDP-rich extrudates. In conclusion, top-down approach is a promising strategy to explore the mechanisms of ASDs' dissolution, and small amount of SDS enhances the dissolution rate of polymer-rich ASDs in the nonsink condition.  相似文献   
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Dipeptidyl‐peptidase‐4 (DPP‐4) inhibitors, as the most recent available anti‐diabetic agents, were generally used in clinical treatment of type 2 diabetes (T2DM). In addition to anti‐diabetic effects, the five most widely used DPP‐4 inhibitors (sitagliptin, vildagliptin, saxagliptin, linagliptin and alogliptin) also exert cardiovascular protective effects. In recent years, increasing studies suggest that sitagliptin shows pleiotropic impacts towards the cardiovascular system either with or without diabetes. In this review, we summarized the recent reports to provide an update discussion about cardiovascular protective effects of sitagliptin and the corresponding mechanisms. Sitagliptin has positive effects towards ischaemic cardiovascular diseases, atherosclerosis and hypertension. These effects are mainly conducted through DPP‐4 inhibitions. In addition, sitagliptin exerts anti‐inflammation, anti‐oxidative stress, anti‐apoptosis, mediation on lipid accumulation and so on, which also contribute to its cardiovascular effects.  相似文献   
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We have developed a new set of lyophilized kits, composed of 3 different kits, for the instant preparation of no‐carrier‐added 131I‐MIBG in the clinic. We here discussed the formulation of the kits, optimization of radiolabelling, quality control of radiolabeled 131I‐MIBG, and studies of animal biodistribution. The no‐carrier‐added (nca) 131I‐MIBG injection could be prepared within 30 minutes in the clinic with the help of the lyophilized kits. The radiochemical purity and specific activity (SA) could achieve above 98% and 6700 MBq/mg, respectively.  相似文献   
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