Objective To study the relationship of ampicillin resistance and?lactamase production, and gene mutation on pbp5 gene fragment in Enterococcus faecium. Methods?lactamase production was tested with nitrocefin, the pbp5 gene fragment of 57 isolates of ampicillin-resistant Enterococcus faecium (ARE. faecium) was amplified by PCR, the mutation of amplified pbp5 gene was detected by single-strand conformation polymorphism(SSCP), the specific mutation types were confirmed by sequencing. Results?lactamase was negative in 57 isolates of ARE. faeciums; there were 3-6 gene mutation sites on pbp5 gene fragment, and the frequent mutation sites were the position 485 ,499 and 466'. Conclusion The gene mutation of pbp5 gene fragment may play an important role in the ARE. faecium.

Objective:To explore changes of electrocardiogram (ECG)and cardiac markers,and its relationship with prognosis in aged patients with acute cerebral infarction.Methods:The data of 356 aged patients with acute cerebral infarction (acute cerebral infarction group),who hospitalized in our hospital from May 2007 to May 2012,and 258 non-cerebral infarction patients (normal control group)were retrospectively analyzed.Changes of ECG and cardiac markers were compared between two groups,and patients with cerebral infarction received a six-month follow-up. Results:Compared with normal control group,there were significant rise in percentage of abnormal ECG (22.9%vs.73.3%,χ2=150.53,P=0.00),levels of cardiac troponin I [cTnI,(0.02±0.003)μg/L vs.(0.07±0.002)μg/L],creatinine kinase isoenzyme [(9.1±5.6)U/L vs.(24.2±4.1)U/L]and creatinine kinase [(98±9.8)U/L vs.(202.7±10.2)U/L]in acute cerebral infarction group,P<0.05 all;the older these patients were,the high-er abnormal ECG rate was (60~75 years vs.>75 years:37.0% vs.83.8%,χ2=80.54,P=0.00);After six-month follow up,compared with normal group,there was significant increase in mortality rate (19.5% vs.86.8%,χ2=95.09,P=0.00)in acute cerebral infarction group.Conclusion:Incidence rate of abnormal ECG and cardiac marker level are higher in aged patients with acute cerebral infarction.It possesses important significance for judging patient′s condition,guiding treatment and evaluating prognosis.

Objective To establish CT image-based, three-dimensional finite element models of healthy tibiae and plateau-fracture tibiae, and to calculate the displacement and stress distribution of the tibial models .Methods Continuous-time tomographic images of knee joints of a healthy adult and a patient with tibial plateau fractures were obtained using multi-slice spiral CT scan , and inputed to Mimics to establish three-dimensional surface mesh models of tibiae .The models underwent global meshing procedures and material properties assignment to construct finite element models of normal and plateau-fracture tibiae in ANSYS , and the newly established models were analyzed and calculated .Results In case of applied load on the tibial plateau , the peak strains of the load-contact sites in the healthy subject and the patient presented divergent directions , with peak strains on the medial tibia in the healthy subject and lateral tibia in the patient , respectively . Equivalent stress decreased gradually down the tibiae and concentrated in the one -third of the upper and middle regions in both types of tibiae .Moreover, concentration of stress was also present in the locus of the fractured tibia .The deformation displacement gradients were more evident in the healthy tibia than in the fractured tibiae .There was significant difference in overall stress distribution between the two types of tibiae .Conclusion Three-dimensional finite element models of tibiae have been established that can demonstrate the differences in biomechanical properties between healthy and plateau -fracture tibiae, which might provide reference and guidance for orthopedic regimens .