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Summary Measurement of biotransformation activities in cells is of great importance for drug metabolism and toxicologic studies. It is currently done by measuring the enzymatic activities in partially purified microsomes. In the present work we report on a rapid, easy, sensitive, and reproducible fluorimetric assay for quantifying cytochrome P450-dependent monooxygenase activities (P450IA1, P450IIB1) in hepatocytes cultured in 96-well plates. The procedure involves the direct determination of enzymatic activities in intact hepatocytes while avoiding cell homogenization, thereby permitting use of a the reduced number of cells and allowing cultured cells to be used in later experiments. Substrates (7-ethoxyresorufin, 7-pentoxyresorufin) are added to culture medium and metabolized by hepatocytes. After enzymatic deconjugation, the fluorescent resorufin present in culture medium is quantified by means of a microplate fluorimetric reader. Major advantages of this technique, as compared to other available methods, are: a) no cell disruption is required; b) activity can be measured with a very small number of cells; c) rapid processing time; and d) possibility of performing repeated assays with the same cell monolayer.  相似文献   
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免疫吸附治疗在肾移植致敏受者中的应用   总被引:2,自引:0,他引:2  
目的:探讨蛋白A免疫吸附(immunoads Orption,IA)治疗对清除肾移植致敏受者体内特异性抗HLA抗体的疗效和安全性。方法:10例肾移植致敏(PRA〉50%)受者用彤新蛋白A免疫吸附柱行IA治疗,测定治疗前后血免疫球蛋白及PRA水平。结果:10例患者IA治疗次数为4~15次(中位数9)。所有患者IA治疗后血清总IgG水平都明显下降(P〈0.001),IgA和IgM也较治疗前显著降低(P〈0.01)。PRA8例转阴,1例〈30%,1例仍为100%。结论:对于肾移植致敏受者,IA是一种特异性高、安全有效的治疗措施。  相似文献   
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张生杰  焦文温  张瑜  华素  韩光 《中草药》2012,43(12):2390-2395
目的 采用星点设计-效应面法优化异穿心莲内酯固体脂质纳米粒(IA-SLN)处方工艺,并考察其体外释放特性.方法 采用薄膜-超声分散法制备IA-SLN,以包封率、粒径、Zeta电位为评价指标,考察载体比例、投药量、聚山梨酯80质量分数3因素对制备工艺的影响,并对结果进行方程拟合,用效应面法预测最佳工艺条件;采片用透析法研究IA-SLN体外释放机制.结果 包封率、平均粒径、Zeta电位都以二项式拟合最优,复相关系数R2分别为0.985 6、0.913 6、0.933 4,根据优化方案制备的IA-SLN包封率96.62%、平均粒径162.4 nm、Zeta电位-31.6 mV.IA-SLN体外释放符合non-Fick's扩散机制,药物扩散和脂质骨架溶蚀具有协同作用.结论 星点设计-效应面法可用于IA-SLN的工艺优化,所建立的数学模型预测性良好.  相似文献   
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Objective:Type 1 diabetes autoantibodies are directed against multiple antigens including: glutamic acid decarboxylase, protein tyrosine phosphatase-like islet antigen 2 (IA2), insulin (IAA), and Zinc transporter 8 protein (ZnT8). The aim of our study was to determine if the presence or titer of ZnT8 antibodies (Ab) was predictive for clinical presentation at diagnosis or for the subsequent disease course.Methods:Between January, 2003 and May, 2019, 105 patients aged ≤21 years with a clinical diagnosis of type 1 diabetes mellitus had at least 1 autoantibody measured. A retrospective chart review was completed. At diagnosis, we evaluated the body mass index z-score, hemoglobin (HbA1c), and the presence of diabetic ketoacidosis (DKA). Complications analyzed post-diagnosis included episodes of DKA, the diagnosis of autoimmune disease, and the presence of vascular complications. We evaluated cumulative lifetime excess glucose as HbA1c area under the curve (AUC) >6%.Results:Seventy-one patients were ZnT8-Ab(+) (68%), with 19 having low titer ZnT8-Ab and 52 with high titer ZnT8-Ab. Follow-up ranged from 10 days to 15.7 years (median 2.08 years). There were no differences in the characteristics at disease onset or in the subsequent follow-up between those with and those without ZnT8-Ab or those with high or low titers of ZnT8 Ab, except for a small but statistically significant difference in cumulative excess glucose (HbA1c AUC >6%) between those with low and high titers (p=0.0095).Conclusion:Our study adds to the limited literature on the effect of the presence and titer of ZnT8-Ab in pediatric diabetes. The small effect of ZnT8-Ab titer on glucose excess as measured by HbA1c AUC warrants further study.  相似文献   
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Objective

To compare the efficacy of intra-articular (IA) steroid injection and distension in patients with frozen shoulder.

Data Sources

Databases, including MEDLINE (via PubMed), Embase, Scopus, and Cochrane Library, were searched for studies published up to November 2016.

Study Selection

We included all published randomized controlled trials (RCTs), quasi-experimental studies, and observational studies investigating the effectiveness of IA steroid injection, distension, and physiotherapy in patients with frozen shoulder. Sixteen RCTs and 1 observational study were enrolled in meta-analysis.

Data Extraction

Full texts were independently reviewed, and quality of RCTs was assessed with The Cochrane Collaboration's tool. The primary outcome was functional improvement; the secondary outcomes included pain reduction and external rotation (ER) improvement.

Data Synthesis

In pairwise meta-analysis, pooled standardized mean difference (SMD) of functional improvement and pain reduction revealed equal efficacy at 3 follow-up time points. With respect to ER improvement, distension has a superior effect compared with IA steroid injection in the short term [(2–4wk; SMD, ?.36; 95% confidence interval [CI], ?.68 to ?.04) and medium term (6–16wk; SMD, ?0.80; 95% CI, ?1.32 to ?0.29). The network meta-analysis indicated a better efficacy for distension than for IA steroid injection in ER improvement only in the medium term (6–16wk; SMD, ?0.70; 95% CI, ?1.19 to ?0.21).

Conclusions

IA steroid injection was as effective as distension in shoulder function improvement, pain reduction, and increasing ER of the shoulder. Distension yielded better ER improvement in the medium term but to a minor extent in the long term. For patients with predominant ER limitation, early distension could be considered the primary choice of treatment.  相似文献   
10.

Objective

To quantify the effects of initial hip angle and angular hip velocity settings of a lower-limb wearable robotic exoskeleton (WRE) on the balance control and mechanical energy requirements in patients with paraplegic spinal cord injuries (SCIs) during WRE-assisted sit-to-stand (STS).

Design

Observational, cross-sectional study.

Setting

A university hospital gait laboratory with an 8-camera motion analysis system, 3 forceplates, a pair of instrumented crutches, and a WRE.

Participants

Patients (N=12) with paraplegic SCI.

Interventions

Not applicable.

Main Outcome Measures

The inclination angle (IA) of the body’s center of mass (COM) relative to the center of pressure (COP), and the rate of change of IA (RCIA) for balance control, and the mechanical energy and forward COM momentum before and after seat-off for energetics during WRE-assisted STS were compared between conditions with 2 initial hip angles (105° and 115°) and 3 initial hip angular velocities (800, 1000, 1200 rpm).

Results

No interactions between the main factors (ie, initial hip angle vs angular velocity) were found for any of the calculated variables. Greater initial hip angle helped the patients with SCI move the body forward with increased COM momentum but reduced RCIA (P<.05). With increasing initial angular hip velocity, the IA and RCIA after seat-off (P<.05) increased linearly while total mechanical energy reduced linearly (P<.05).

Conclusions

The current results suggest that a greater initial hip angle with smaller initial angular velocity may provide a favorable compromise between momentum transfer and balance of the body for people with SCI during WRE-assisted STS. The current data will be helpful for improving the design and clinical use of the WRE.  相似文献   
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