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991.
992.
Data suggest that nutrient order during a meal significantly impacts postprandial glucose and insulin excursions in type 2 diabetes, while its effects in prediabetes have not been reported. Fifteen participants with prediabetes consumed the same meal on 3 days in random order: carbohydrate first, followed 10 minutes later by protein and vegetables (CF); protein and vegetables first, followed 10 minutes later by carbohydrate (PVF); or vegetables first followed by protein and carbohydrate (VF). Blood was sampled for glucose and insulin measurements at 0, 30, 60, 90, 120, 150 and 180 minutes. Incremental glucose peaks were similarly attenuated by >40% in the PVF and VF meal conditions compared with CF. The incremental area under the curve for glucose was 38.8% lower following the PVF meal order, compared with CF, and postprandial insulin excursions were significantly lower in the VF meal condition compared with CF. The CF meal pattern showed marked glycaemic variability whereas glucose levels were stable in the PVF and VF meal conditions. Food order presents a novel, simple behavioural strategy to reduce glycaemic excursions in prediabetes.  相似文献   
993.
The standard endoscopic surgical approach in the management of laryngeal lesions is by the use of a laryngoscope, microscope, and laser. This requires the surgeon to work within the confines of the laryngoscope. At times, it requires repositioning of the laryngoscope and microscope to gain access to a specific area. The surgery also requires line-of-sight observation to complete the operation. The introduction of transoral robotic surgery in head and neck surgery brings the advantages of three-dimensional magnification, increased degrees of freedom with the effector arms, and an articulating distal end that mimics hand movements. To date, transoral robotic surgery of vocal cord surgery requires the use of a tracheostomy in patients. Here we report the use of a CO(2) laser fiber and the Da Vinci robotic platform (Intuitive Surgical) for the surgical management of a T1 glottic squamous cell carcinoma.  相似文献   
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Factors associated with suicidal ideation and attempts were examined among a national probability sample of adolescents. Sample prevalences of suicidal ideation and attempts were 24.3% and 3.3%, respectively, yielding weighted population prevalence estimates of 23.3% and 3.1%. Suicidal ideation was positively associated with female gender, age, family alcohol and drug problems, violence exposure, lifetime depression, and posttraumatic stress disorder (PTSD). Suicide attempts were associated with female gender, age, sexual and physical assault, lifetime substance abuse or dependence, PTSD, and depression. Implications for intervention and prevention are discussed.  相似文献   
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目的探讨后路椎间盘镜下腰椎间盘摘除术(MED)及传统开放腰椎间盘摘除术对腰椎生物力学稳定性的影响。方法选用6具新鲜尸体脊柱标本,模拟后路腰椎间盘摘除的不同术式,依次对标本腰3~4间隙进行处理,共设计5种减压情况:MED、半椎板切除、半椎板切除并下关节突1/2切除、半椎板切除并下关节突全部切除和全椎板切除髓核摘除术。在力学实验机上分别对实验标本进行前屈/后伸、左/右侧屈及左/右轴向旋转运动,测量不同运动的最大范围。结果模拟MED手术脊柱标本向各个方向的运动与正常对照组比较差异无统计学意义(P>0.05);半椎板切除术、半椎板切除并下关节突1/2切除后,标本向各个方向的运动除半椎板切除并下关节突1/2切除后右侧旋转外与正常对照组差异无统计学意义(P>0.05),半椎板切除并下关节突全部切除后,标本向各个方向运动与正常对照组比较差异均有统计学意义(P<0.05,右侧旋转P<0.01);模拟全椎板切除标本向各个方向的运动与正常对照组比较差异均有统计学意义(P<0.01)。结论MED手术对脊柱破坏性较小,对稳定性无影响,而半椎板并小关节切除则破坏了稳定性。  相似文献   
1000.

Background and purpose:

This study establishes a pharmacokinetic/pharmacodynamic (PK/PD) model to describe the time course and in vivo mechanisms of action of the antinociceptive effects of lumiracoxib, evaluated by the thermal hyperalgesia test in rats.

Experimental approach:

Female Wistar fasted rats were injected s.c. with saline or carrageenan in the right hind paw, followed by either 0, 1, 3, 10 or 30 mg·kg−1 of oral lumiracoxib at the time of carrageenan injection (experiment I), or 0, 10 or 30 mg·kg−1 oral lumiracoxib at 4 h after carrageenan injection (experiment II). Antihyperalgesic responses were measured as latency time (LT) to a thermal stimulus. PK/PD modelling of the antinociceptive response was performed using the population approach with NONMEM VI.

Results:

A two-compartment model described the plasma disposition. A first-order model, including lag time and decreased relative bioavailability as a function of the dose, described the absorption process. The response model was: LT=LT0/(1 +MED). LT0 is the baseline response, and MED represents the level of inflammatory mediators. The time course of MED was assumed to be equivalent to the predicted profile of COX-2 activity and was modelled according to an indirect response model with a time variant synthesis rate. Drug effects were described as a reversible inhibition of the COX-2 activity. The in vivo estimate of the dissociation equilibrium constant of the COX-2-lumiracoxib complex was 0.24 µg·mL−1.

Conclusions:

The model developed appropriately described the time course of pharmacological responses to lumiracoxib, in terms of its mechanism of action and pharmacokinetics.  相似文献   
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