Volume 92  ·   Issue 09  ·  2012

Alzheimer's disease (AD), also known as senile dementia, is a degenerative brain disease characterized by progressive dementia. It is common in the elderly, and its incidence increases gradually with age. The incidence rate is 3.0% in the age of 65-74, 18.7% in the age of 75-84, and 47.2% in the age of over 85. It is estimated that there will be 22 million AD patients in the world by 2025, and the number of AD patients will increase to 45 million by 2050. AD has become the fourth cause of death in developed countries after cardiovascular diseases, tumors and stroke. At present, the number of AD patients among the elderly over 60 years old in China has reached 3-4 million, and the huge social burden brought by it has become a public health problem that cannot be ignored. Therefore, the research on AD has become one of the research hotspots of senile diseases. In recent years, the rapid development of neuroimaging has prompted the huge change of medical imaging mode. magnetic resonance spectroscopy (MRS), as a non-invasive imaging method to study the changes of metabolite levels in living tissues and organs, is an important method for early diagnosis and diagnosis of AD

Objective To study the dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI ) features of VX2 rabbits carcinoma metastatic and inflammatory lymph nodes.Methods Twenty healthy adult New Zealand white rabbits were divided into metastatic lymph node group and inflammatory lymph node group randomly. There were ten rabbits in each group. All 20 rabbits underwent DCE-MRI.Peak enhancement,time to peak,maximum slope and signal intensity versus time curves were generated from each node individually.Results DCE-MRI were obtained for nine cases of metastatic lymph nodes and nine cases of inflammatory lymph nodes.The signal intensity versus time curves of metastatic lymph nodes were appeared as rapid ascending and plateauing,and peak enhancement,time to peak,maximum slope of metastatic lymph nodes group were 284％ ± 125％,(118 ±47) s and (6.5 ±2.7) ％/s,respectively.The signal intensity versus time curves of inflammatory lymph nodes were appeared as insisting ascending,and peak enhancement,time to peak,maximum slope of inflammatory lymph nodes group were 199％ ± 109％,( 143 ± 40) s and ( 3.6 ± 1.5 ) ％/s,respectively.There was significantly higher peak enhancement,shorter time to peak and higher maximum slope in the metastatic lymph nodes group compared with the inflammatory lymph nodes group (P ＜ 0.05 ). Conclusions DCE-MRI can accurately reflect the hemodynamic characteristics of VX2 rabbits neoplasm metastatic lymph nodes and inflammatory lymph nodes,and can differentiate VX2 rabbits neoplasm metastatic lymph nodes from inflammatory lymph nodes.

Objective To evaluate the value of diffusion-weighted imaging (DWI) in the differentiation of axillary inflammatory hyperplastic and metastatic lymph nodes. Methods Forty female New Zealand white rabbits were divided randomly into 2 groups (n =20 each).And the animal models of axillary inflammatory hyperplastic and metastatic lymph nodes were established.All successfully implanted models received conventional magnetic resonance imaging (MRI) and diffusion-weighted imaging (DWI) examinations.The features of signal intensity and shapes of lymph nodes were observed in two groups.The sizes of lymph nodes were measured on the selected axial T2WI. The signal intensity and appearance diffusion coefficient (ADC) value of lymph nodes and dorsal muscle at the same slice were measured on the selected T2WI,DWI and ADC map respectively.The relative signal intensity (rSIT2WI,rSIDWI ) and relative ADC (rADC) value of lymph nodes to dorsal muscle were calculated and compared.The diagnostic efficacy of differentiating benign and malignant lymph nodes was analyzed with rADC value through the receiver operating characteristic curve. The correlation between rADC value and cell density was assessed with pathological findings as reference standard.Results The differences of size,rSIT2WI and rSIDWI were not statistically significant between two groups.The rADC value of inflammatory lymph nodes was greater than that of metastatic lymph nodes (0.91 ± 0.14 vs 0.64 ± 0.18 ).Significant difference existed ( t =3.879,P =0.03 ).But there was a little overlap between two groups.With 0.78 as the diagnostic threshold of rADC value,the sensibility and specificity was 86.2％ and 74.4％ respectively.The correlation between rADC value and cell density of inflammatory hyperplastic and metastatic lymph nodes was significantly inverse (r =- 0.53,P =0.003 ).Conclusion As compared with the routine MRI sequence,rADC value has a higher diagnostic efficacy in the differentiation of benign and malignant lymph nodes.Cell density may be the most important influencing factor for the differences of rADC value between two groups of lymph nodes.

Objective To evaluate the magnetic resonance (MR) imaging and proton magnetic resonance spectroscopy (1H-MRS) in the diagnosis of pediatric hematological diseases.Methods A total of 35 cases with pediatric hematological diseases were confirmed by bone marrow puncturing.There were acute leukemia (n =26),aplastic anemia (n =6),thalassemia (n =2) and autoimmune hemolytic anemia (n =1 ).All cases and thirty age-marched healthy children underwent MR imaging (T1 WI,T2WI,STIR) and 1 H-MRS of lumber spine and ilium.The lumber spines and iliums were studied by observation of MR imaging and calculation of fat fraction (FF％).Results Two patterns were classified by MR imaging and 1H-MRS in lumber spines and iliums of all cases.Pattern 1:hyperplasia of bone marrow (BM).There were acute leukemia (n =26 ),thalassemia (n =2 ) and autoimmune hemolytic anemia (n =1 ). The manifestations included homogeneous low signal intensity (SI) on T1 WI,homogeneous low SI on T2 WI,high SI on STIR and high water peak and low fat peak on 1 H-MRS.The FF％ s of regions of interest (ROI) in lumber 4s and left iliums of 26 cases with acute leukemia were 0％,of 3 cases with thalassemia or autoimmune hemolytic anemia were 5.02％ and 3.70％.Pattern 2:inhibition of BM.There were 6 cases of aplastic anemia.The manifestations included homogeneous or inhomogeneous high SI on T1WI and T2WI,homogeneous or inhomogeneous low SI on STIR,and low water peak and high fat peak on 1 H-MRS.FF％ s of ROI in lumber 4s and left iliums for 6 cases of aplastic anemia were 74.69％ and 91.51％.FF％ in all groups had significant differences according to the Mann-Whitney test (P ＜ 0.05 ). Conclusion MR imaging and 1 H-MRS may serve as a noninvasive method for checking hematopoietic status of bone marrow in pediatric hematological diseases.

Objective To evaluate the potential functional reorganization by functional magnetic resonance imaging (MRI) to measure the brain activation in responses to stimulation to healthy ears in patients with long-term unilateral hearing loss (UHL).Methods From June 2008 to December 2009,23 patients with serious UHL ( 15 left,8 right) were recruited along with 15 matched normal hearing subjects.Laterality index (LI) for activated voxel in primary auditory cortex (PAC) was calculated.And the activations outside auditory cortex were also evaluated.Results The data were discarded in 3 patients with left-ear UHL and 1 normal subject because of head motion. All control subjects showed contralateral dominant activation of PAC in group analysis. However,the group data of UHL patients showed that the activation was more symmetrical and the contralateral dominance diminished versus the control group.As compared with normal subjects outside PAC,heightened activation in left prefrontal cortex,bilateral inferior parietal lobule and left occipital/precuneus was found in UHL patients while reduced activation in left superior temporal gyrus was also found.Conclusion The diminished contralateral dominance in PAC and heightened activation in non-auditory region suggest the reduction of interhemispheral inhibition and general increase in brain excitation in long-term UHL patients potentially occur as a result of functional reorganization adaptive to UHL.However,the reduced activation in superior temporal gyrus may be correlated with the deterioration of speech perception in these patients.

Objective To construct the functional networks of human brains by resting-state functional magnetic resonance imaging (fMRI) and examine whether or not the small-world property of functional brain networks changes in patients with Alzheimer disease (AD).Methods A total of 33 AD patients and 20 healthy old volunteers were recruited.Their cognitive functions were evaluated by the minimental state examination (MMSE) and Mattis dementia rating scale (DRS).The resting-state BOLD-fMRI data were acquired and preprocessed. Then the correlation coefficient of every pair of 90 regions was calculated and correlation matrix Z ( N × N,N =90) generated by Fisher Z transformation.The small-world property of functional brain networks was tested for AD patients and normal elders according to the definition of small-worldness.The changes of relevant parameters in AD patients were examined by two sample t-tests.Results Behavioral results:the MMSE scores of AD group and normal controls (NOR) were 20.6 ± 2.3and 28.2 ± 1.8 respectively. The DRS scores of AD and NOR groups were 96 ± 11 and 123 ± 14 respectively.The MMSE and DRS scores were statistically different between two groups. Calculation of small-world parameters:Within the range of 0.1 ≤ Sparsity ≤ 0.4,both groups satisfied the small-world property.However,the clustering coefficient Cp and the average shortest path Lp of AD group were significantly higher than those of NOR group at each threshold (P ＜ 0.05).Conclusion The functional brain networks in AD patients still have the property of small-world.But the levels of Cp and Lp are higher in AD patients than those in normal controls. It suggests that the capacity of information transmission in functional brain networks and the ability of information integration in different brain regions in AD patients are impaired.This finding is of great importance in elucidating the pathological mechanisms of AD from the viewpoint of networks.

Objective To explore the clinical efficacies and outcomes of regional method axis pedicle screw insertion technique.Methods During the period of April 2004 to June 2010,a total of 23 cases with traumatic instability of upper cervical vertebrae were recruited.There were 19 males and 4 females with a mean age of 45.8 years.They underwent surgical operations after an excellent traction reduction of cervical vertebrae.The entry points were drawn on axial facet joint and all of them distributed in the region of upper inner 1/4 of lower articular process. So the regional method was employed to determine the entry point.All subjects underwent the reconstruction of posterior stability.Axial pedicle screws were inserted by the insertion technique of axial pedicle screw via the “regional method”.The entry region was in the upper inner 1/4 area of lower articular process.The entry angle,medial inclination and superior inclination were determined by the direction of inner wall and upper wall of isthmus.Postoperative cervical radiography and CT examination were performed to confirm the screw position.Results Forty-six axial pedicle screws were implanted.No significant complications occurred. All screws stayed in excellent positions without the invasion of vertebral artery and spinal canal.Conclusion The “regional method” insertion technique of axial pedicle screw require no memory of complex entry points and entry angle parameters.And there is no need of identifying the anatomical landmarks.Thus this approach is accurate,safe and suitable for most patients.

Objective To assess the clinical and radiographic outcomes of posterior lumbar fixation and posterior interbody fusion or improved transforaminal lumbar interbody fusion for Meyerding grade Ⅱ/Ⅲ spondylolisthesis so as to address the suitability of a dynamic stabilization. Methods A total of 28 consecutive patients underwent posterior lumbar fixation and posterior interbody fusion or improved transforaminal lumbar interbody fusion for Meyerding grade Ⅱ/Ⅲ spondylolisthesis. Among them, 13 patients underwent posterior interfacet fusion (PLIF) and pedicle screw fixation. And improved transforaminal lumbar interbody fusion (ITLIF) and placement of the same system were performed in 15 patients. Their clinical, economic, functional, and radiographic data were recorded both pre- and postoperatively.Results The average changes of economic and functional scores on the Prolo scale were 1.36 and 1.48 respectively.In patients with posterior interbody fusion; the average preoperative vertebral slippage was 46.9％ ( range:25％ - 75％ ) versus 14.6％ ( range:15％ - 25％ ) postoperatively.In patients with ITLIF, the average changes in economic and functional scores were 1.75 and 1.63 respectively.And the average preoperative vertebral slippage was 45.2％ (range:28％ -78％ ) compared with 26.3％ (range:14％ -28％ ) postoperatively.When two fusion techniques were compared,an overall superior reliability and resistance of systems was associated with the ITLIF procedure. But their clinical outcomes did not differ greatly ( P ＞ 0.05 ).Conclusion The application of a segmental pedicle screw fixation is both feasible and efficacious.

Objective To explore the differences of estrogen receptor a (ERa) gene polymorphism in patients with missed abortion and normal pregnancy and examine the relationship between ERa gene polymorphism and missed abortion.Methods A total of 100 cases of missed abortion patients and 102 cases of normal pregnant women were selected as the experimental and control groups. And 2ml blood samples and chorionic villus specimens were collected.The method of polymerase chain reaction restriction fragment length polymorphism was employed for ERa gene PvuⅡ and XbaⅠ polymorphism.And the data was analyzed to explore the relationship between ERa gene polymorphism and missed abortion.Results There was statistic significance in the frequency of ERa gene PvuⅡ enzyme cleavage allele P and p from blood and villi samples between two groups,blood ( x2 =5.542,P ＜ 0.05 ) OR:1.742,villi ( x2 =7.559,P ＜0.01 ),OR:1.948.Statistic significances existed in the difference of frequency for ERa gene XbaⅠ enzyme cleavage allele X and x from blood and villi samples between two groups,blood (x2 =15.205,P ＜0.01 ),OR:2.519; villi (x2 =13.750,P ＜ 0.01 ),OR:2.499.There was a positive correlation of the frequency in ERa gene PvuⅡ and XbaⅠ genotype from blood and villi samples in the experimental group.Conclusion It suggests that ERa gene polymorphism is correlated with the pathogenesis of missed abortion.Alleles P and X may be susceptibility genes.

Objective To explore the attentional bias in unilateral spatial neglect (USN) patients.Methods The grey discriminant test was conducted on 12 right-brain-damaged patients with USN (USN + ),12 right-brain-damaged patients with no evidence of USN ( USN - ) and 20 health controls (HC).They were matched for age,years of education,mini-mental state examination (MMSE) scores and handedness.And all patients were recruited from First Affiliated Hospital of Anhui Medical University.The attentional deviation scores were compared between three groups. Results The differences in scores of neglect tests for the USN +,USN - and HC groups were significant ( Albert test:USN + group - 0.56 ± 0.39,USN - group 0.00 ± 0.00,HC group 0.00 ± 0.00,F(2,41 ) =33.708,P ＜ 0.001 ; line bisection test:USN+ group0.28 ±0.29,USN- group 0.03 ±0.04,HC group -0.02 ±0.04,F(2,41) =14.527,P ＜ 0.001 ; clock drawing by memory:USN + group 3.58 ± 4.03,USN - group 0.08 ± 0.29,HC group 0.00 ± 0.00,F(2,41 ) =12.558,P ＜ 0.001 ; daisy copying:USN + group 0.83 ± 0.65,USN -group 0.13±0.23,HC group 0.00 ±0.00,F(2,41) =21.621,P＜0.001).The comparative results of lesion locations showed that USN + patients were predominantly related to lesions in temporal-parietal junction.The attentioanl deviation scores for the USN +,USN - and HC groups were 0.92 ±0.11,0.41 ±0.12 and -0.28 ±0.15 respectively.The difference was significant ( F(2,41 ) =334.324,P ＜ 0.001 ).There was a small leftward bias in the HC group and a rightward bias in the USN + and USN - groups.LSD test revealed that the USN + group displayed a rightward bias much strongerly than the USN - group ( P ＜0.001 ).And the results of grey discriminant test were consistent with the neglect symptoms.Conclusion The USN patients show a marked attentional bias toward the right side of space.And it may be attributed to the dysfunction of temporal-parietal junction.

Objective To identify differentially expressed lumcian in scleral tissue of eyes with primary open-angle glaucoma (POAG) and high mopia (HM).Methods Total RNA was isolated from scleral tissue of cadaveric eyes derived from normal donors,patient's eyes with diagnosed glaucoma and high mopia who accepted trabeculectomy. RNA was amplified,RT-PCR was used to measure the levels of mRNA.The ratio of the electrophoresis strips'gray scale values of the β-actin over the lumican gene was obtained for ANOVA analysis.Results β-actin/LUM of normal eye was significantly higher than that of POAG and POAG + HM eyes (P ＜ 0.01 ),but there was no significant difference between POAG and POAG + HM eyes (P ＞ 0.05).Conclusion Differentially expressed lumican between POAG and control groups identified in this study have not been previously investigated for their role in the pathogenesis of POAG and thus are novel factors for further study of the mechanism of the disease and for their possible use as diagnostic markers.

Objective To explore the medium and long-term outcomes of patients with Moyamoya disease (MD) undergoing surgery and conservative treatment at a single institution and analyze the related prognostic factors.Methods A retrospective review was conducted for 97 MD patients at Beijing Tiantan Hospital from January 2000 to December 2007.They were divided into 3 groups according to treatments:superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis ( n =31 ),indirect vascular revascularization group (n =38) and conservative treatment group ( n =28).The primary follow-up events included death,recurrent cerebral hemorrhage,new cerebral infarction and transient ischemic attack (TIA).Results All were available for analysis with the complete follow-up data.The average follow-up period of was 85 ± 38 months.In total,there were 6 deaths with all-cause mortality (6.1％ ).Among them,5 (5.1％) patients died from recurrent cerebral hemorrhage.And 17 episodes of rebleeding occurred in 11 patients.Two episodes of intracranial hemorrhage were found in 4 patients. The risk of rebleeding was 17.5％.In the STA-MCA group,23 (74％)cases had excellent recovery,5 cases fared worse and there was no death case. Among the patients undergoing indirect vascular revascularization,28 cases recovered favorably,4 cases progressed and 3 cases died.In the conservative treatment group,17 patients recovered favorably,7 progressed,9 experienced 15 episodes of rebleeding and 3 died.Multivariate Cox regression analysis showed that the method of treatment was an independent prognostic factor for MD and surgical revascularization was superior to conservative treatment.No correlation was found between the patient age,gender,familial history,unilateral or bilateral and prognosis(P ＞ 0.05).Kaplan-Meier stroke risk analysis showed the risk of recurrent hemorrhage in the revascularization surgery group was lower than that in the conservative group. And no difference existed between STA-MCA and indirect arterial anastamoses.Conclusion Rebleeding is a major cause of poor prognosis,mobility and mortality in MD patients.Surgical revascularization offers better long-term outcomes than conservative treatment. And direct arterial anastamoses may decrease recurrent hemorrhage effectively.

Objective To explore the application value of positron emission tomography (PET) in the localization of magnetic resonance imaging ( MRI)-negative epileptogenic focus.Methods Brain images of 18fluoro-2-deoxy-D-glucose ( 18 F-FDG) and 13 N-NH3· H2O-PET,MRI and video electroencephalography (VEEG) were obtained in 65 patients.Preoperative and postoperative localizations were compared in MRI-negative patients.And the results of PET and VEEG were compared between the MRI-positive and MRI-negative groups.Results MRI scans were normal in 26 cases and abnormal in 35 cases.Sixty-one patients had interictal epileptiform discharge on VEEG (brain regions,n =12; multiple brain areas,n =16;hemisphere,n =13; unspecified location,n =20) and interictal PET imaging (brain regions,n =23;multiple brain areas,n =28 ; hemisphere,n =5 ; unspecified location,n =6). And 17 MRI-negative patients underwent operations and 12 of them reached the Engels Ⅰ - Ⅱ level standard. Both PET and VEEG were compared between the MRI-positive and MRI-negative groups.No significant differences existed between two group (P ＜ 0.05).A comparison of PET and VEEG showed statistical significance in two group (P ＞ 0.05).Conclusion PET imaging is both sensitive and effective in the detection and localization of epileptogenic foci.Especially for MRI-negative cases,it is an indispensable tool of localizing epileptogenic foci.

Objective To explore the expression of heat shock protein 27 (HSP27) in the CA1 area of hippocampus in temporal lobe eplepsy (TLE) so as to elucidate the relationship between HSP27 and epleptogenesis of TLE.Methods The model of TLE was induced by lithium-pilocarpine in the experiment group.And the rats were further divided into the STLE and non-STLE groups based upon the absence or presence of recurrent spontaneous seizure in the next 30 days. Total protein fractions from CA1 area of hippocampus were successively obtained through tissue homogenated abstraction.The HSP27 expression in the CA1 area of hippocamp from three groups was semi-quantitatively analyzed by Western blot.And the expression of HSP27 in CA1 area was detected by pre-embedding immunogold electron microscopy.Results Expression of HSP27 in the hippocampus CA1 area as detected by Western blot was in accord with that by immunogold electron microscopy.Relative optical density values were 0.912 ± 0.011,0.431 ± 0.011 and 0.428 ±0.010 respectively.And gold particles were 50.0 ±4.2,23.0 ±2.8 and 20.0 ±2.3 respectively.The expression of HSP27 was the highest in the hippocampus CA1 area of the STLE group. There was statistical significance as compared with the non-STLE and normal groups (P =0.0001 ).The non-STLE group was higher than the normal group.But there was no significant difference as compared with the normal group ( P =0.63).Conclusion HSP27 in the hippocampus CA1 area may participate in the epleptogenesis of TLE.

Objective To explore the role and mechanism of Duffy antigen receptor for chemokines (DARC) of tissue in promoting the inflammatory reaction of the limb with venous hypertension.Methods Femoral arteriovenous fistula was surgically created to establish the rat model of venous hypertension.A total of 36 SD rats were randomly divided into pcDNA3.1-DARC ( Group A),empty plasmid of pcDNA3.1 (Group B) and control (Group C) groups.The animals were sacrificed at Days 14 and 42 post-operation respectively.The expressions of DARC at the RNA and protein level were detected by real-time polymerase chain reaction (Real-PCR) and Western blotting.And the serum level of interleukin (IL)-8 was detected by enzyme linked immunosorbent assay (ELISA) and the degrees of apoptosis and leukocytic infiltration of local tissue were detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) and hematoxylin and eosin (HE) staining.Results With the elapsing time of venous hypertension,the DARC expression in tissue,the extent of apoptosis and leukocytic infiltration in tissue showed an increasing trend in Groups A and B.Group A was obviously higher than Group B during the corresponding period.And the differences were statistically significant (P ＜ 0.05).The serum levels of IL-8 of Groups A and B showed a decreasing trend.And Group A was obviously lower than Group B. Both groups were higher than the control group. The differences were statistically significant ( P ＜ 0.05 ).Conclusion The level of DARC in tissue and the degree of inflammatory reaction of venous hypertension have a positive correlation.And DARC may promote the development of venous hypertension inflammation through augmenting the adhesion and migration of leukocytes.

Objective To investigate the feasibility of method improved for developing septic shock rats model.Method Studies were performed on 60 adult male Sprague-Dawley rats.They were randomized into sham group and standard CLP (J Group)group(n =20),A(n =10),B(n =10),C(n =10) group and J group was further to two subgroups (n =10) J1 and J2 group.The ligated distance of A,B and C group were 20％,30％,50％ of the cecum respectively.Standard CLP procedures were made in J group as described previously.Sham group just sham operated.MAP was monitored continuously in A,B,C and J1 groups for 5 h,and the MAP droped to 70％ of the baseline was defined as septic shock,MAP was monitored for more than 10 hours until it reached 70％ of baseline or lower in the J2 group.The white blood cell count,endotoxin and histopathological changes in lung and renal tissue were observed in each groups.Results At 5 h after operation,there is no change of MAP in sham,J1,A and B groups,but it dropped to 70％ of the baseline [ (73 ± 10) mm Hg] in C group.Compared with sham group,the level of endotoxin [(17±5) vs (456 ±28) vs (596±29) vs (982±11) vs (209 ±40) pg/ml] and white cell count [ (6.3 ±3.7) vs (4.6±1.4) vs (3.7 ±1.2) vs (3.3 ±2.6) vs (4.2±1.2) × 109/L] was significantly higher and lower respectively in A,B,C and J1 groups.Obvious pulmonary and nephridial tissue edema,inflammatory cell infiltration was observed in C group,but the inflammatory cell infiltration was not found in A,B and J1 groups,The manifestations of J2 group rats is similar with C group.Conclusion The rat model produced by ligating 50％ cecum can reproduce the pathophysiology of septic shock,and the time needed to prepare septic shock was significantly shorter.The improved model has application value for septic shock study.

Objective To examine the roles of exercise training in the improvement of damaged neural function and synaptic plasticity.Methods An infarction model was induced by left middle cerebral artery occlusion (MCAO).A total of 70 adult Sprague-Dawley rats were randomly divided into 3 groups:physical exercise group (n =30) undergoing running wheel exercise daily after MCAO,control group (n =30) and sham-operated group (n =10).The latter two groups were fed in standard cages without any special training exercise.The rats were scarified at Days 3,7,14,21 and 35 for the evaluation of neural function by neurological severity scores (NSS). And the synaptic ultrastructures at peri-infarction region were examined by specific marker synaptophysin (SYN).Results Synaptic ultrastructures at peri-infarction region were observed in both the control and exercise training groups. The presynaptic and postsynaptic membranes were relatively intact.And the presynaptic membranes had more synaptic vesicles from Day 7 post-ischemia.The number of SYN positive cells significantly increased in the exercise training group(21 d:0.8 ±0.1 ; 35 d:0.7 ±0.1 )versus those in the control group (21 d:0.4 ±0.1 ; 35 d:0.5 ±0.1 ) at Days 21 and 35 post-ischemia (P ＜ 0.05 ). Moreover,the neurological severity scores in the exercise training group (7 d:7.8 ± 0.8 ; 14 d:5.6 ± 0.8 ; 21 d:3.3 ± 0.8 ; 35 d:3.0 ± 0.8 ) showed a quicker declination versus those in the control group (7 d:8.8 ±0.7; 14 d:7.7 ±0.9; 21 d:6.9 ±0.8; 35 d:4.2 ±0.8) from Day 7 post-ischemia (P ＜ 0.05).Conclusion Exercise training plays an important role in the recovery of damaged neural function and synaptic plasticity after cerebral infarction in rats.

As the most successful treatment for end-stage hip diseases, total hip arthroplasty has a 20-year survival rate of more than 80%. The long-term effect of artificial joint is mainly affected by aseptic loosening caused by periprosthetic osteolysis. The main cause of osteolysis is the biological response induced by prosthetic wear particles (especially polyethylene particles), so interface wear has always been an important issue of concern for joint surgeons and instrument manufacturers [1]. The design of prostheses with metal-to-polyethylene friction interface, the appearance of highly crosslinked ultra-high molecular polyethylene materials and the combination of ceramic-to-polyethylene, metal-to-metal and ceramic-to-ceramic friction interfaces significantly reduce the generation of wear particles and the osteolysis around prostheses induced by this [2].

A 27-year-old female was admitted to the First Hospital of Peking University on March 8, 2011 because she had been on the ring for more than 3 months and was found to have an intrauterine device incarcerated for 2 months. The patient usually had regular menstruation, 3/29 d, moderate amount, dysmenorrhea (-), last menstruation on February 19, 2011, 2 pregnancy and 2 delivery, and the patient had 2 cesarean sections in 2007 and May 2010, respectively. After the last delivery, she has been breastfeeding. On November 24, 2010, she placed an intrauterine device in a local primary hospital (the specific ring type is unclear), and immediately felt lower abdominal distension, pain, dizziness and chest tightness after self-complaining of being on the ring, and improved after rest. After operation, she always felt lower abdominal distension, pain, discomfort, accompanied by back pain, no vaginal bleeding, and normal defecation.