Objective To study the neurotoxicity of lead to mice and the mechanism. Methods Two months old(grown) and two weeks old(infancy) mice were employed, 1 ?l of 1 mol/L lead acetate was given by brain ventricle injection, 3 d, 5 d, 1 week, 2 weeks and 3 weeks after treatment with lead, the change of autonomic activities and the ability of study and memory of the mice were examined. Results The latency period of Lashley Ⅲ water maze prolonged significantly in grown group and the infancy group compared with the control groups at every time point of test. Conclusion Lead exposure can damage the function of study and memory of mice, and increase the frequency of autonomic activities of theirs.

Objective To explore the mechanism of the influence on mice brain of environmental tobacco smoke. Methods After the mice were placed into the bench for 8 weeks, the region of the mice brain was localized and the expression of neurotransmitters and neurotransmitters receptors were detected by immunohistochernistry.Results ( 1 ) The expression of GABA in the mice cerebral cortex ( CC ) ( 0. 25 ± 0. 06 ) and the hippocampus (Hip) (0. 19 ± 0. 07 ) were much higher in the ETS-exposed group than that in the control group(P＜ 0. 05 ). (2)The expression of nAChR on CC(0. 31 ±0. 10) was much more in the ETS-exposed group than that in control group(P＜0.05). (3) The expression of NMDAR( Glu receptors) on the CC and striate cortex were much higher in the ETS-exposed group(0.32 ±0. 10,0.38 ±0. 14), NIC-inhaling group(0.31 ±0. 08,0.31 ± 0. 11 ) than that in control group(P＜0. 05 ). Conclusions Long-term ETS-exposed and NiC-exposed environment could change the expression of neurotransmitter and its receptors.

AIM: To investigate the mechanism by which TA9902 inhibits the formation of amyloid ?-peptide (A?) fibrils. METHODS: Fourier-transform infrared spectroscopy was used to study the secondary structure changes on aging A? in vitro. RESULTS: The content of ?-pleated sheet were 46.53% in the condition of A? aged alone for 30 min. When A? aged alone for 72 h, the content of ?-pleated sheet increased about 19.4% and produced a shift of random coil toward ?-pleated sheet. TA9902 induced a significant decrease in the content of ?-pleated sheet (36.09%). CONCLUSION: TA9902 effectively diminishes the ?-pleated structural content. The effect of TA9902 on the secondary structure of aged A? is associated with inhibition of A? aggregation and fibril formation.

BACKGROUND:The conservative treatment of humeral fracture is difficult to achieve a good reduction. Minimaly invasive percutaneous plate fixation has been widely used, and has good repair results, but the specific mechanism of action is not clear.
OBJECTIVE:To compare the repair effect of different fixation methods on proximal humerus fractures.
METHODS: From August 2011 to October 2014, we selected 96 patients with proximal humerus fractures from the Shougang Hospital of Peking University. These patients were equaly divided into two groups according to the principle of random draw. Patients in the control group were treated with open reduction and conventional surgery fixation. Patients in the treatment group received minimaly invasive percutaneous plate fixation. Operation time, intraoperative blood loss, incision length and postoperative hospital stay were recorded in both groups. At 8 weeks after treatment, patients received radiography to identify the reduction. Range of motion of the shoulder joint was scored. Within 8 weeks after treatment, the occurrence of complications was observed and compared in both groups.
RESULTS AND CONCLUSION:Intraoperative blood loss, incision length and postoperative hospital stay were significantly less in the treatment group than in the control group (P < 0.05). No significant difference in operation time was found between the two groups (P > 0.05). At 8 weeks after treatment, the excelent and good rate of reduction was significantly higher in the treatment group than in the control group (98%, 81%,P < 0.05). Flexion, abduction, external rotation and internal rotation scores were significantly higher in the treatment group than in the control group (P < 0.05). Bone compartment syndrome, vascular injury, infection and bleeding were significantly lower in the treatment group than in the control group (P < 0.05). These findings confirm that compared with open reduction and internal fixation, minimaly invasive percutaneous plate fixation of proximal humerus fractures has less impact on the body, can promote reduction of the fracture, has few complications, and contributes to the recovery of shoulder function.

Objective To evaluate CT and MRI findings of portal vein aneurysm(PVA)in order to improve its diagnostic accuracy.Methods CT and MRI findings of 9 patients with PVA proved by pathology and direct angiography were reviewed retrospectively.CT scanning was performed in 7 patients,including plain scan (n=2),both plain and enhanced scan (n=5),CT angiography (CTA)(n=3).Plain and enhanced MRI scan were performed in 3 patients.Results (1 )PVA showed a high predilection for old adults.(2 )Of the 9 tumors,4 located in portal vein trunk,2 located in junction of superior mesenteric vein and portal vein trunk,1 located in intrahepat-ic-extrahepatic portal vein,2 located in intra-hepatic portal vein.(3)8 tumors were characterized as well-defined and quasi-circular mass.1 patient occurred portal hypertension,thrombus as the portal vein trunk was oppressed by the tumor.(4)Plain CT showed the mass was slightly higher than pancreas parenchyma density,and uniform with the density of the liver parenchyma.Enhancement scanning showed 4 tumors represented mild or moderate enhancement in portal venous phase except for 1 patient accompany with portal vein thrombus.CTA showed clearly the relationship mass with portal vein,and classified the type of PVA .The 3 lesions represented hypo-intensity on T1 WI and even hyper-intensity on T2 WI.Enhancement scanning showed the tumor was significantly enhancement in portal venous phase on T1 WI.Conclusion CT and MRI have their own advantages in the diagnosis of portal vein aneurysm.Com-bination of CT and MRI could improve the diagnostic accuracy of portal vein aneurysm.

Most researchers consider that high exposure to heavy metals can result in hemorrhagic gastritis,hepatonecrosis,cancer,even death.There are many routes for heavy metals to get into human body,for instance absorption by gastrointestinal tract,cutaneous absorption etc.In this paper,the author reviewed the recent researches on brain function damage induced by heavy metals via olfactory pathway.Some heavy metals have especial affinity with brain tissue and cause functional disorder and death of nerve cells,and the mechanisms were discussed in detail.

Objective To evaluate the clinical applied value of spiral CT during arterial portography(SCTAP)in evaluating the surgical resectabitity of the hepatocellular carcinoma(HCC).Methods 23 patients with focal hepatic lesions (including HCC 21 cases) were examed with SCTAP,convenient CT and DSA.The difference and the sensitivity in detecting the number of lesions by these three examied methods were comparatively analysed.Results SCTAP had significant difference in comparision with convenient CT and DSA (?0.05) when the lesions were more than 30.0 mm in diameter.21 cases of HCC hepatic metastatic lesions were not found by SCTAP in 9 cases,they chosen the surgical treatment,and 12 cases underwent the interventional trans-catheter artenial chamical embolism(TACE),because of hepatic metastasis showed by SCTAP.Conclusion SCTAP is of high sensitivity in showing small hepatocellular carcinoma and small liver metastatic lesion in comparision with convenient CT and DSA,and it is of great clinical applied value in judging the patients with HCC whether can be or not be treated by surgery.

AIM: To clarify if TA9901, a natural antioxidants, could inhibit the formation of ?-amyloid(A?) fibril when A? 1-40 were injected into cerebral cortex of rat brain, and explore the mechanism of action of TA9901 on Alzheimer disesse. METHODS: Twelve Wistar rats (250-300 g) were randomly divided into four groups ( n=3 ). (1) control group; (2) TA9901 treatment group (ip. 100 mg?kg -1 ?d -1 ); (3) Vitamin E(VE) treatment group (ip. 100 mg?kg -1 ?d -1 ); (4) PBS group. 5 ?L 0.2% A? 1-40 was immediately injected into the right side of the deep cerebral cortex of control, TA9901 and VE group rats. The animals were sacrificed at the seventh day after the injection. The sections of the rat brain that contained the injected field were examined with transmission electron microscopy and Congo red staining with polarized microscopy. RESULTS: Many depositions of high electron density were observed by electron microscopy in the field where A? 1-40 was injected. They are intimately intermingled with macrophages and astrocytes. In the field, about 10nm fibrillar structures were observed that appeared similar to the fibrils seen in senile plaque (SP) of the brain of Alzheimer disease (AD). The fields in control and VE group contained richer A? fibrils than that in TA9901 group. After the sections stained with Congo red, A? 1-40 aggregation demonstrated intense birefringence under, indication the formation of amyloid fibrils. In TA9901 group, there was a weak birefringence.CONCLUSIONS: TA9901 can inhibit the fibril formation of A? that was injected into deep cerebral cortex of rat brain, this indicates primarily that TA9901 may be a potential therapeutic drug to interfere with the progression of amyloidgenesis in AD.

AIM:To gain the molecular mechanism of active ingredients of EGb 761(ginkgo flavones and ginkgo lides) for the inhibition against A?_(1-42) aggregation and fibrogenesis.METHODS:Circular dichroism spectra(CD) and FI-IR were used to curve-fit and analyze the change in A?_(1-42) second structure under A? aged condition and intervention of ginkgo flavones and ginkgo lides.RESULTS:Analysis that was made of 1700-1600 m(-1) amide-Ⅰ-band and curve fitting indicated that after 30 min to 72-incubation,increase of ?-sheet in A?_(1-42) by(18.5%),but the reduction of ?-sheet by(50.95%) and(36.09%) in 72 h incubation with ginko flavones and ginkgo lides,respectively.And increase of ?-turn by(56.56%) and(46.56%) in sane condition.CONCLUSION:Obviously,?-sheet turned into ?-turn.-CH_2 and-CH groups of ketones and alkanes engaged in A?_(1-42) molecular change.

Objective To explore the practice teaching model of human anatomy through re-forming the practice teaching of system anatomy and regional anatomy. Methods Three classes of clinical medicine (5-year program) were randomly selected as reform experimental classes and the other 3 classes of the same grade were used as control classes. The teaching content of practice teach-ing was reformed in the experimental classes. In the system anatomy practice teaching, the teacher controlled the teaching process and developed the theme and requirements of each experimental class while the student completed the experiment developed by the teacher. In the regional anatomy practice teaching, students' interest in learning was stimulated by the content , which was related with the surgery, and the teacher guided students to complete the operation. In control classes, the forms of student observation as well as teacher answering questions and helping students were adopted. The student grading was divided into theoretical knowledge examination and specimen assessment and the achievement was analyzed by using a Simple Analysis of Variance (ANOVA) in SPSS 16.0. Results Compared with those of control classes, the scores of system anatomy and regional anatomy in experi-mental classes were significantly increased (80.7±5.8) vs. (67.4±17.4), (85.1±4.6) vs. (62.6± 12.4) and the theoretical scores of system anatomy were also improved significantly. But no significant difference in theoretical scores of regional anatomy was observed. Conclusions The teaching mode based on the practice teaching highlights the academic characteristics of the human anatomy, increas-es students' interest in learning and improves the effectiveness of practice teaching in human anatomy.