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Objective To study the effects of different residual stromal bed thickness (RSBT) in laser-assisted in situ keratomileusis (LASIK) surgery on geometric deformation and stress changes of the cornea under different intraocular pressures (IOP), and evaluate safety of the three retention values (250, 280, 300 μm). Methods The models of normal cornea and corneas with different RSBT after surgery were established by the finite element software ABAQUS. Appropriate loading and boundary conditions were set and then the corresponding displacement and stress were calculated. Results The apical displacement of the postoperative cornea (RSBT=250 μm) under IOP=2.66 kPa was basically the same as that of the normal cornea (RSBT=550 μm) under IOP=5.32 kPa. RSBT=280 μm was in the low risk area of keratoconus, while RSBT=250 μm was in the high-risk area. At a value between 280 μm and 300 μm of RSBT, the stress distribution was nearly consistent with that of the normal cornea. With RSBT=300 μm, the stromal layer of the cornea lost 40% of the strongest strength against tissue tension. Conclusions RSBT=250 μm is the minimum retention value for LASIK surgery. RSBT=250 μm is the high risk value. With RSBT=330-340 μm, LASIK surgery is safe enough for most patients.
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Objective@#To investigate the impact of gender and age on in-hospital major adverse cardiovascular and cerebrovascular events of patients with acute ST-segment elevation myocardial infarction (STEMI).@*Methods@#This is a retrospective single-center study. A total of consecutive 1 102 patients with acute STEMI admitted to our hospital from January 2001 to December 2010 were recruited and clinical data were analyzed. The primary end point was in-hospital death due to any cause, and the secondary end point was in-hospital composite end point including death, re-infarction and stroke. Multivariate logistic regression analyses were performed to identify the risk factors of in hospital death and composite end point.@*Results@#The study population included 283(25.7%(283/1 102)) female patients and female patients were older than male patients ((68.7±11.2)years vs. (59.2±12.5)years, P<0.001). Compared with male patients, less female patients received primary percutaneous coronary intervention (50.9%(144/283) vs. 70.9%(581/819), P<0.001), had higher rates of in hospital death(10.6%(30/283)vs. 6.0%(36/819), P<0.001) and composite endpoint(14.1%(40/283)vs. 7.0%(57/819), P<0.001). Among STEMI patients aged <60 years, no differences were found in in-hospital mortality (1.7%(1/58)vs. 1.4%(6/437)) and composite endpoint(3.6%(3/58)vs. 3.4%(15/437)) rates between female and male patients (both P>0.05). Among STEMI patients aged ≥60 years, female patients had higher in-hospital mortality (12.9%(29/225)vs. 7.9%(30/382), P<0.001), and there was no difference on composite endpoint between female and male patients (16.4%(37/225)vs. 11.0%(42/382), P=0.054). Multivariate logistic regression analysis showed that female gender was not the independent risk factor of in-hospital death(OR=1.029, 95%CI 0.564-1.877, P=0.926) and composite end point(OR=1.593, 95%CI 0.989-2.566, P=0.055), but age was the independent risk factor of in-hospital death(OR=1.065, 95%CI 1.037-1.094, P<0.001) and composite end point(OR=1.050, 95%CI 1.029-1.071, P<0.001)in STEMI patients. Multivariate logistic regression analysis also showed that female was not the independent risk factor of in-hospital death(OR=1.539, 95%CI 0.572-4.142, P=0.394) and composite end point(OR=1.563, 95%CI 0.689-3.546, P=0.285), but age was the independent risk factor of in-hospital death(OR=1.052, 95%CI 1.011-1.096, P=0.013) and composite end point(OR=1.042, 95%CI 1.008-1.077, P=0.016)in STEMI patients received primary percutaneous coronary intervention.@*Conclusion@#Female patients with STEMI have higher incidence of in-hospital major adverse cardiovascular and cerebrovascular events than male patients, and age is the independent risk factor of in-hospital major adverse cardiovascular and cerebrovascular events of STEMI patients.
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Bioavailable studies were performed based on plasma concentrations of captopril in 5 Beagle dogs and 5 male healthy volunteers after a single oral administration of captopril sustained-release tablet and sugar-coated tablet. A one-compartment model was adopted. Relative bioavailability of sustained-release tablet to sugar-coated one was 131.6% for dogs and 111.0% for humans. Their mean residence times (MRTs) were 4.52 h and 1.96 h in dogs, 4.28 h and 2.77 h in humans, respectively. The maximum concentrations were 995.9 ng/ml and 2470.8 ng/ml in dogs, 126.2 ng/ml and 251.2 ng/ml in humans for two kinds of tablets, respectively. The duration time, in which plasma concentration staved above 50% inhibitory concentration of angiotensin converting enzyme activity, was more than 10 h for sustained-release tablets and 6h for sugar-coated tablets at the same dose (37.5 mg). consequently, it could be expected that the sustained-release tablet dosed twice a day should have a greater efficiency than marketed sugar-coated tablet taken 3 times daily.