This paper analyzes the reasons of the graduates'disadvantages of obtaining jobs,brings forward the countermeasures,emphasizing the cultivation of the students'ability and quality so that the graduates can have more employment chance.

Objective To investigate the effects of partial hepatectomy on spatial learning and memory abilities and the expression of spinophilin,which was used as a marker to quantify changes in dendritic spine density in the hippocampus of APP/PS1 transgenic mice.Methods 3-month-old and 6-month-old male APP/PSI transgenic mice and 3-month-old wild-type male littermates were divided into five groups based on their genetic background:3-month-old control (group A,n =8),anesthesia (group B,n =32),surgery (group C,n =32),littermates control(group D,n =8),6-month-old control (group E,n =8).According to the different time points at day 1,3,7,14 after anesthesia or surgery,group B and C were divided randomly into 4 subgroups:B1,B3,B7,B14 and C1,C3,C7,C14.The spatial learning and memory abilities were detected by Morris water maze test in each group at the corresponding time points.Meanwhile,spinophilin expression was detected by Western blot and Immunocytochemistry in the hippocampus.Results Compared with the same time point subgroup B,the latency to find a hidden platform was longer and the frequency of passing through the platform was decreased in Group C at day 3,7,14(P ＜ 0.05).No significant differences were found among group A,group D,and group B (P ＞ 0.05).The grey value and Western blot relative integrated optical density of spinophilin in group A(1 609 453 ±92 801/0.471±0.015),approached the Group D(1 329 398.4±77 783/0.434±0.008)(P＞0.05),were significantly increased compared with that(801 678 ± 10 505/0.053 ± 0.003) in group E (P ＜ 0.01).Compared with the Group A,the same time point subgroup B and subgroup C14,the grey value and Western blot relative integrated optical density of spinophilin were decreased in Group C at day 1,3,7 (P ＜ 0.05).Conclusion Partial hepatectomy can impair spatial learning and memory abilities of the APP/PS1 transgenic mice,which is closely related to the decrease expression of spinophilin in hippocampus.

Objective To study the influences of hepatolobectomy on space learning capability and the expressions of Drebrin and PSD95 in the hippocampus in APP/PS1 transgenic mouse model of Alzheimer's disease.Methods A total of fifty-four 3-month-old APP/PS1 transgenic mouse were randomly divided into 3 groups:3-month-old control group,sham surgery group,hepatolobectomy group,3-month-old littermates control group and 6-month-old control group.Morris water maze test was used to observe space learning capability on the 1st,3rd,7th,14th day after surgery,meanwhile the expressions of Drebrin and PSD95 in hippocampus were measured by Western blotting.Results Compared with the sham surgery group,the results of the Morris water maze test were decreased in hepatolobectomy group at day 3,7,14 after surgery [(62.9±6.9) s vs.(35.7±12.2) s,(66.3± 9.5) s vs.(39.3±8.3) s,(67.1±7.5) s vs.(32.6±14.1) s],and 6-month-old control group [(75.9±12.1) s] (all P＜0.05).The escape latency were (62.9±6.9)s,(66.3±9.5)s,(67.1± 7.5)s and (75.9±12.1)s,the probe trials were (2.1±0.7) times,(1.83±1.5) times,(2.5±1.9) times and (1.8±0.8) times respectively in hepatolobectomy group at day 3,7,14 after surgery and 6-month old control group.No significant differences in the results of the Morris water maze test were found among 3-month-old control group,3-month-old littermates control group,and sham surgery group.Compared with 3-month-old control group and sham surgery group atday 1,3,7,14 after surgery the expressions of Drebrin were decreased in 6-month-old control group and the hepatolobectomy group at the same time points.Meanwhile,the expression of Drebrin in hepatolobectomy group was increasedat day 14 versus day 7 after surgery.Compared with 3 month-old control group,the expression of Drebrin was increased at day 7 after sham surgery.Compared with 3-month-old control group and sham surgery group at day 3,7 and 14,the expressions of PSD95 were decreased in hepatolobectomy group at the same time points.Compared with 3-month-old control group,the expression of PSD95 was increased in sham surgery group at 7th day (P＜0.05).Between 3 month-old control group and 3-month-old littermates control group,the expressions of Drebrin and PSD95 had no significant differences.Concltsions Hepatolobectomy can impair the capabilities of space learning and memory in 3-month-old APP/PS1 transgenic mice,which may be associated with the decreased expressions of Drebrin and PSD95 in hippocampus.

Objective To investigate the effect of celastrol on space learning capability and expressions of beta-amyloid (Aβ) 40 and Aβ42 in hippocampus in APPswe/PS1dE9 double transgenic mouse after partial hepatolobectomy.Methods The 3-month-old APPswe/PS1dE9 double transgenic mice (n =96) were randomly divided into three groups according to the random number table method.Surgery group (group S, partial hepatolobectomy;n =32), celastrol group (group C, injections of dimethyl sulphoxide/DMSO and celastrol for 3 days before undergoing partial hepatectomy, on the surgery day, and for a further 4 days after surgery;n =32), and DMSO group (group D, injections of DMSO for 3 days before undergoing partial hepatectomy, on the surgery day, and for a further 4 days after surgery;n =32).Eight mice were selected randomly in each group and were Morris-water maze trained for continuous 5 days.Theirs learning and memory abilities were evaluated at 1,3, 7 and 14 d after surgery, respectively.Hippocampus was collected and the changes of β40 and Aβ42 were measured by enzyme-linked immunosorbent assay (ELISA) at the time set in advance in each group.Results The average escape latency of group C was significantly shorter than groups S and D at 3, 7 and 14 d after partial hepatectomy (P ＜ 0.05).Times of passing through the platform groups S and D were significantly less than group C (P ＜ 0.05).The expressions of Aβ40/Aβ42 in group C were lower than group S and group D at 1, 3, 7 and 14 d after partial hepatectomy (P ＜ 0.05).Conclusions Through decreasing the expressions of Aβ40 and Aβ42 in hippocampus,celastrol improves the space learning capability in APPswe/PS1dE9, the double transgenic mouse after partial hepatolobectomy.

Spinal cord injury (SCI) can lead to severe sensory and motor dysfunction pathologically characterized by direct axonal rupture, nerve cell necrosis and apoptosis. Traditional interventions, such as drug therapy and cell therapy, have limited efficacy associated with a poor prognosis in patients of SCI. In recent years, exosomes have become a new hotspot for spinal cord injury repair for their unique phospholipid properties and nucleic acid and protein inclusions. Exosomes can be produced by various cells with the assistance of molecules related to intracellular vesicle transport, such as endosomal sorting complex proteins, rat sarcoma-associated proteins and lipids. Those exosomes with structural and functional diversity due to the molecular composition of their respective cell sources, can be targeted on different receptor cells and play a key role in inhibiting glial scar formation, reducing inflammation and promoting nerve regeneration and repair. By identifying the target of exosomes derived from mesenchymal stem cells, neural stem cells, and Schwann cells for spinal cord injury repair, individualized therapy becomes possible based on the specific cell and molecular background of the patient's injury type, thus enhancing the effectiveness and safety of therapy. However, clinical use of exosomes still has limitations because of its rapid clearance, unstable therapeutic concentration in injured site and lack of separation and purification methods that both satisfies the separation efficiency and specificity. On the basis of the separation and purification methods summarized by International Society of Extracellular Vesicles, efforts are made by using 3D culture and stimulation of physical and chemical factors to improve exosome production and activity, using synthetic extracellular vesicle mimics with higher yield to replace exosomes and loading exosomes with scaffolds such as hydrogels and 3D printing materials to provide a stable environment for promoting nerve repair.

Objective:To analyze and evaluate the items of the general module of multidimensional health measurement instruments system for elderly patients with chronic disease (MHIEC-GM)(V1.0) based on classical test theory (CTT) and item response theory (IRT).Methods:A self-administered survey of 2 375 elderly patients with chronic diseases was conducted using the MHIEC-GM(V1.0) scale. The quality of items was analyzed using the variability method, correlation coefficient method, factor analysis method, and Cronbach's α coefficient method based on CTT. The difficulty coefficient, differentiation coefficient, and information content of items were analyzed using the IRT analysis software MULTILOG 7.03.Results:The CTT results showed that the standard deviations of all nine items were greater than 0.9. The results of the correlation coefficient method, the factor analysis method and the Cronbach′s α coefficient method showed that except for the GMI9 item, the correlation coefficients between the other items and the total scale were all greater than 0.5, and the factor loads were all greater than 0.5, and the Cronbach′s α coefficients after the deletion of the items were all less than 0.763. Based on the results of the four analysis methods, except for the GMI9 item, all the other items had good characteristics. The IRT results showed that the information contents of all items were >0.333 (5/15) except for the GMI4, GMI6, and GMI8, and the differentiation coefficient of each item was 1.44. The items that difficulty coefficient met the [-4, 4] inclusion criteria were the GMI2, GMI3, GMI5, GMI7 and GMI9, showing a monotonically increasing trend with increasing difficulty level. The items of GMI1, GMI4, GMI6, and GMI8 needed further improvement.Conclusion:Most of items of the MHIEC-GM(V1.0) scale have good psychometric properties, but some items need to be further revised and validated according to the characteristics of chronic diseases in the elderly.

OBJECTIVE: To investigate the preparation and properties of the novel silica (SiO ₂)/hydroxyapatite (HAP) whiskers porous ceramics scaffold. METHODS: The HAP whiskers were modified by the SiO ₂ microspheres using the Stöber method. Three types of SiO ₂/HAP whiskers were fabricated under different factors (for the No.1 samples, the content of tetraethoxysilane, stirring time, calcination temperature, and soaking time were 10 mL, 12 hours, 560℃, and 0.5 hours, respectively; and in the No.2 samples, those were 15 mL, 24 hours, 650℃, and 2 hours, respectively; while those in the No.3 samples were 20 mL, 48 hours, 750℃, and 4 hours, respectively). The phase and morphology of the self-made HAP whisker and 3 types of SiO ₂/HAP whiskers were detected by the X-ray diffraction analysis and scanning electron microscopy. Taken the self-made HAP whisker and 3 types of SiO ₂/HAP whiskers as raw materials, various porous ceramic materials were prepared using the mechanical foaming method combined with extrusion molding method, and the low-temperature heat treatment. The pore structure of porous ceramics was observed by scanning electron microscopy. Its porosity and pore size distribution were measured. And further the axial compressive strength was measured, and the biodegradability was detected by simulated body fluid. Cell counting kit 8 method was used to conduct cytotoxicity experiments on the extract of porous ceramics. RESULTS: The SiO ₂ microspheres modified HAP whiskers and its porous ceramic materials were prepared successfully, respectively. In the SiO ₂/HAP whiskers, the amorphous SiO ₂ microspheres with a diameter of 200 nm, uniform distribution and good adhesion were attached to the surface of the whiskers, and the number of microspheres was controllable. The apparent porosity of the porous ceramic scaffold was about 78%, and its pore structure was composed of neatly arranged longitudinal through-holes and a large number of micro/nano through-holes. Compared with HAP whisker porous ceramic, the axial compressive strength of the SiO ₂/HAP whisker porous ceramics could reach 1.0 MPa, which increased the strength by nearly 4 times. Among them, the axial compressive strength of the No.2 SiO ₂/HAP whisker porous ceramic was the highest. The SiO ₂ microspheres attached to the surface of the whiskers could provide sites for the deposition of apatite. With the content of SiO ₂ microspheres increased, the deposition rate of apatite accelerated. The cytotoxicity level of the prepared porous ceramics ranged from 0 to 1, without cytotoxicity. CONCLUSION SiO ₂/HAP whisker porous ceramics have good biological activity, high porosity, three-dimensional complex pore structure, good axial compressive strength, and no cytotoxicity, which make it a promising scaffold material for bone tissue engineering.
Animals ; Durapatite ; Porosity ; Vibrissae ; Apatites ; Ceramics ; Silicon Dioxide

Objective To understand the status of family well-being of university and high school students in Guangdong Province,and to analyze the factors affecting students'family well-being.Methods Using cluster sampling,students enrolled in two universities and six high schools in Guangdong Province were collected,and quartile regression was used to analyze the factors affecting the family well-being of these students.Results A valid sample of 4987 cases was obtained with the percentage of students who clearly feel happy being 73.5%.The quantile regression results showed that:gender(Q10,Q25,Q50,Q75),household registration(Q75,Q90),grade level(Q25,Q75),father's occupation(Q75),mother's occupation(Q75),father's education(Q90),freedom to develop hobbies and interests(Q10,Q50,Q75),freedom to make decisions(Q25,Q75),family members'transposition of thinking(Q75),parental interference(Q10,Q25,Q50,Q75),freedom to organize time(Q75,Q90),parental harshness(Q75),parental constraints(Q75),family closeness,family caring level,family atmosphere,and family solidarity are all related to family well-being among university and high school students.Among them,the family well-being are positively related to family closeness,family care,family atmosphere and family solidarity,and negatively related to parental interference.Conclusion Family well-being is relatively high among university and high school students in Guangdong Province.In order to enhance students'well-being,we should increase the degree of intimacy among family members to create a relaxing,happy and warm family atmosphere,and at the same time,parents should moderately reduce the amount of interference in their children's affairs.