Objective:To understand the influencing factors of free education for rural order-oriented medical students and to explore the willingness of students to serve at the grass-roots, so as to provide reference for further optimizing the free education of medical students.Methods:A self-designed questionnaire survey was performed among 196 medical undergraduates majoring in free clinical medicine in one medical university of Shandong Province in March 2018 and 198 undergraduates majoring in general clinical medicine enrolled in the same year. The results of the survey were analyzed by SAS 9.2, and chi-square test, rank sum test and logistic regression were used to make statistic analysis.Results:The factors such as score of the national university entrance exam (wald χ2 = 52.309, P < 0.001), household registration location (wald χ2 = 9.304, P = 0.002), whether the only child in the family (wald χ2 = 12.608, P < 0.001), average monthly income of the family (wald χ2 = 5.557, P = 0.018), decision makers (wald χ2 = 15.206, P = 0.002) and willingness to serve at the grass-roots medical institutions (wald χ2 = 67.832, P < 0.001) had influence on medical students' choice of free education for order directional medical students. There were 113 (57.65%) of the free medical students intended to work at the grass-roots, while only 16 (8.08%) of the general medical students who were willing to work at the grass-roots. Conclusion:The implementation of free education for order-oriented medical students policy can satisfy the wishes of some people who have the willingness to serve at the grass-roots, but their family income and college entrance examination scores are not high. However, there are still some problems, which need the joint efforts of the government health departments and the training colleges and universities, and the corresponding follow-up support policies should be issued by the state at the same time.

Forearm ; innervation ; Ganglion Cysts ; surgery ; Humans ; Male ; Middle Aged ; Muscle, Skeletal ; innervation ; surgery ; Tendons ; surgery ; Ulnar Nerve ; surgery

Objective To measure the serum selenium levels in patient with Keshan disease(KSD)and in healthy controls in Shandong,Sichuan and Inner Mongolia KSD areas,to monitor the long-term dynamic changes of hair and serum selenium levels in Shandong KSD areas,and to provide scientific basis for preventing KSD.Methods A cross-sectional survey was carried out in KSD areas of Shandong,Sichuan and Inner Mongolia in 2009.The research subjects which come from KSD areas were 77 cases and 63 healthy controls from Shandong;35 patients and 36 healthy controls from Sichuan;and 17 patients and 18 healthy controls from Inner Mongolia.Additional 33 healthy people from Jinan city were selected as controls of non-KSD areas.Blood and hair samples were collected and selenium levels were measured by 2,3-diaminonaphthalene fluorescence spectrometry.Retrospective method was used to analyze the hair and serum selenium data collected between 1976 and 2004 in Shandong KSD areas.and these data were eompard with the data of 2009 to observe the long-term dynamic changes.Results ① The serum selenium levels of KSD patients in Shandong and Inner Mongolia were significantly lower than that of healthy subjects of KSD areas[(0.0773±0.0113)vs(0.0895±0.0256),(0.0347±0.0107)vs(0.0469±0.0161),t=3.52,3.87,all P<0.01].No significant difference was found between KSD patients and healthy people in Sichuan[(0.0792±0.0162)vs(0.0774±0.0103),t=0.55,P>0.05].②The serum selenium levels of KSD patients in Shandong,Sichuan and Inner Mongolia KSD areas were lower than that of non-KSD area[(0.0988±0.0231)mg/L,q=6.74,5.83,19.47,all P<0.01].The serum selenium levels of healthy people in Sichuan and Inner Mongoha KSD areas were significantly lower than that of non-KSD area(q=6.68,16.36,all P<0.01).The serum selenium levels of healthy controls in Inner Mongolia were lower than that of in Shandong and Sichuan(q=13.63,14.74,13.62,1.46,all P<0.01).③From 1976 to 2009,the hair and serum selenium levels of Shandong resident were increased 1.68 times(0.343/0.128-1)for hair and 0.98 times(0.091/0.046-1)for serum,respectively.But there was no significant difference between the average growth rate of hair and serum selenium levels(χ2=1.38,P>0.05).Conclusions ①The hair and serum selenium levels of KSD patients are lower than that of healthy controls in non-KSD area.②The serum selenium levels of Shandong,Sichuan and Inner Mongolia are different between KSD patients and healthy controls in the diseased areas.③The hair and serum selenium data of Shandong resident show an upward vend over the past 30 years.We suggest to continue the comprehensive measures of adding selenium in KSD areas.

Humanin(HN,its analogue [Gly14]-Humanin,HNG)was originally identified as an endogenous peptide that protects neuronal cells from apoptosis induced by various types of Alzheimer's disease-related insults.But the relative low content of this peptide in its natural sources limits its further characterization.An expression vector pET32a/HNG was corstructed and transformed it into E.coli BL21 trxB(DE3).HNG was expressed as a fusion protein in the soluble fraction and was purified by nickel affinity chromatography.Subsequently,the purified fusion protein was cleaved by enterokinase and was further purified by reverse-phase HPLC.A 23 mg recombinant HNG(rHNG)from 1 L bacterial culture was purified.The molecular weight of rHNG determined by ESI-MS was 2876.5 Da which was the expected size for correctly processed peptide.The N-terminal amino acid sequence of rHNG determined by Edman degradation method is identical to the theoretical sequence.Neuroprotective bioassay studies of rHNG exhibited its potential neuroprotective effect comparable to that of the natural HNG peptide.

To purify recombinant human nucleoside diphosphate kinase A (rhNDPK-A) and determine its physical and chemical characters, recombinant NDPK-A producing E. coli was cultured in 80L fermentor under high cell density culture (HCDC) conditions. The harvested cells were treated with high pressure to break the cell up, tangential-flow microfiltration to remove the bacteria debris and ultrafiltration to concentrate the filtered solution containing target protein. The crude NDPK-A was purified by ion exchange chromatography with DEAE Sepharose Fast Flow, affinity chromatography with Cibarcron Blue 3GA Sepharose CL-4B and gel filtration with Sephadex G-100. The purity of rhNDPK-A was analyzed with SDS-PAGE and RP-HPLC. The Enzymatic activity was determined with RP-HPLC. The molecular weight (MW) was measured with matrix assisted laser desorption ionization time-of-flight MS (MALDI-TOF MS). The N-terminal residue was sequenced with Edman method. The apparent molecular weight of rhNDPK-A in solution was determined with multiangle laser light-scattering method (MALS). It was found that the purity of rhNDPK-A was 97.3% with SDS-PAGE method and 99.2% with RP-HPLC method. The specific enzymatic activity was (900 +/- 100) u/mg. The molecular weight was 17017, which was 132 less than the calculated value according to the amino acid sequence of NDPK-A. The sequencing result of rhNDPK-A revealed that its N-terminal residue was Ala, which was the second residue on N-terminal of native NDPK-A. The calculated MW of N-terminal deleted rhNDPK-A was 17017, exactly equal to the experimental value. The result of apparent MW determination revealed that rhNDPK-A formed homohexamer in solution with a MW of 102kD. These results suggested that rhNDPK-A possessed character identical to its native counterpart of assembling into hexamer. Confirming the identity of rhNDPK-A to its native counterpart provided a good foundation for drug development and mechanism study of NDPK-A.
Amino Acid Sequence ; Humans ; Molecular Sequence Data ; Molecular Weight ; NM23 Nucleoside Diphosphate Kinases ; chemistry ; isolation & purification ; metabolism ; Recombinant Proteins ; chemistry ; isolation & purification ; Scattering, Radiation ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

OBJECTIVETo probe into the relationship between hypertension and hemodynamic score of cerebral vascular accumulative function by though studying the history of hypertension and level of blood pressure.

METHODSThe database of blood pressure and cerebral vascular hemodynamic indexes (CVHI) were from baseline data and measurement in a cohort. 18,512 participants who met the included criteria were enlisted in the study. The function scores were estimated using uniform methods according to CVHI. Participants were grouped by age, years of having hypertension and level of blood pressure. Differences of the function score between different groups were compared.

RESULTSThe function score in hypertension group was significantly lower than that of normal tension group, which decreased by 13.3 points. Within 5 years of hypertension history, the function score decreased as course of hypertension prolonged. The same trend was found between the score and level of both systolic and diastolic blood pressure. When systolic blood pressure elevated to 140 mmHg or diastolic blood pressure elevated to 95 mmHg, the function score was below 75 points.

CONCLUSIONThere were significant relationship between decrease of the function scores and medical history, course of hypertension as well as level of blood pressure.

Adult ; Age of Onset ; Aged ; Blood Pressure ; physiology ; Cerebrovascular Circulation ; physiology ; China ; epidemiology ; Cohort Studies ; Female ; Hemodynamics ; physiology ; Humans ; Hypertension ; epidemiology ; physiopathology ; Male ; Middle Aged

OBJECTIVETo study the effects of two specific cyclooxygenase inhibitors (SCI), rofecoxib and celecoxib, combined with chemotherapeutic drugs 5-Fu, DDP and VP-16 on gastric cancer cell line BGC-823, and to evaluate whether specific cyclooxygenase inhibitors can be used as a synergetic agent in chemotherapy.

METHODSThe gastric cancer cell line BGC-823 cells were incubated for 48 hours with rofecoxib and celecoxib, 5-Fu, DDP and VP-16 (concentration gradient of 5-Fu, DDP and VP-16:1 microg/ml, 10 microg/ml and 100 microg/ml), or in combination, respectively. MTT working solution was added to each culture and calculated the survival rates of gastric cancer cells. Median-effect principle and Professor Jin's evaluation methods were applied to detect the interaction between the specific cyclooxygenase inhibitors and chemotherapeutic agents.

RESULTSThe inhibition rates of gastric cancer cells were 42.63% +/- 1.26% and 50.67% +/- 2.35% by treatment with 0.1 micromol/L rofecoxib and 50 micromol/L celecoxib, respectively. The inhibition rates of gastric cancer cells by treatment with 5-Fu, DDP and VP-16 at different concentrations (1 microg/ml, 10 microg/ml and 100 microg/ml) were 39.75% +/- 3.14%, 49.96% +/- 2.08%, 87.93% +/- 3.66%; 48.28% +/- 2.08%, 59.46% +/- 1.69%, 88.23% +/- 4.81%; and 29.23% +/- 3.27%, 49.34% +/- 3.75%, 79.24% +/- 2.44%, respectively. However, the inhibition rates showed a synergetic role while combined the two SCI (0.1 micromol/L rofecoxib and 50 micromol/L celecoxib) with chemotherapeutic agent at different concentrations (P <0.05).

CONCLUSIONBoth rofecoxib and celecoxib have an ability to suppress gastric cancer cells in vitro, and the synergetic role becomes evident when rofecoxib and celecoxib are combined with chemotherapeutic agents at different concentrations, which indicate that the two specific cyclooxygenase inhibitors may be used as a chemotherapeutic sensitizer.

Adenocarcinoma ; pathology ; Antimetabolites, Antineoplastic ; pharmacology ; Antineoplastic Agents ; pharmacology ; Celecoxib ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cell Survival ; drug effects ; Cisplatin ; pharmacology ; Cyclooxygenase 2 Inhibitors ; pharmacology ; Cyclooxygenase Inhibitors ; pharmacology ; Dose-Response Relationship, Drug ; Drug Synergism ; Etoposide ; pharmacology ; Fluorouracil ; pharmacology ; Humans ; Lactones ; pharmacology ; Pyrazoles ; pharmacology ; Stomach Neoplasms ; pathology ; Sulfonamides ; pharmacology ; Sulfones ; pharmacology

OBJECTIVETo study the risk factors and abusers' characteristics on childhood sexual abuses among female students to provide reference data for preventive measures on child sexual abuse.

METHODSAnnonymous questionnaire survey of 701 adult female students in a college about their personal experience on childhood sexual abuses, their home conditions and abusers' characteristics.

RESULTSA total number of 701 female students were surveyed. 115 (22.11%) experienced non-physical contact sexual abuses before the age of 18, including 26 (3.71%) who suffered from attempted and 8 (1.14%) were forced with genital or anal sexual intercourse. 117 (16.69%) said they had suffered from sexual abuse before the age of 16. Most abusers were males (99.4%) and only a small percentage of them (3.2%) used violence. Most non-physical contact sexual abuses were from strangers (78.7%), while 71.3% of physical contact abuses were from acquaintances including 12.5% of them were teachers, 17.5% were neighbors and 21.3% were relatives. The risk factors of child sexual abuses were: frequent use of violence, bad hobbies and poor health conditions of parents, tight family relationships, and living in remarried families. Having well-educated fathers was a preventive factor.

CONCLUSIONStudies on childhood sexual abuses among females revealed that the incidents were not rare, and family environment played an important role.

Adult ; Child ; Child Abuse, Sexual ; statistics & numerical data ; China ; Family Relations ; Female ; Humans ; Risk Factors ; Students ; statistics & numerical data ; Surveys and Questionnaires ; Universities

Objective To observe the incidence and clinical characteristics of chronic Keshan disease in recent years, and to provide evidence for diagnosis of the disease. Methods From March to August 2009, 163 patients with chronic Keshan disease were chosen from Shandong, Sichuan, Inner Mongolia and Cansu. Of these patients, 62 cases were from Shandong, 34 cases from Sichuan, 37 cases from Inner Mongolia, and 30 cases from Gansu. All of the subjects underwent detailed natural history of the disease, careful physical examination and electrocardiogram (ECG), X-ray chest radiography and cardiac ultrasound examination. The incidence and clinical features were analyzed. Results Adults accounted for 98.8%(161/163) and children for 1.2%(2/163) in 163 cases of chronic Keshan disease, with an average age of 45.8 years. Slow onset accounted for 62.6%(102/163), other types that evolved into chronic-type accounted for 37.4%(61/163). Low blood pressure( 116.5/72.4 mmHg),often with cardiac function grade Ⅱ accounted for 65.6%(107/163). Common symptoms were: palpitation[86.5%(141/163)], asthma [76.7% (125/163)], fatigue[76.1%(124/163)], precordial discomfort [54.6% (89/163)], dizziness[50.3%(82/163)], edema of lower limbs[44.8%(73/163)], and anorexia[38.0%(62/163)]. Common signs were: low-weak first heart sound[66.9%(109/163)], heart enlargement[64.4%(105/163)], apical pulse dispersion[42.3%(69/163)], arrhythmia[40.5%(66/163)], hepatomegalia[39.3%(64/163)], systolic murmur [25.2%(41/163)], and edema[20.9%(34/163)]. Abnormal ECG detection rate was 93.9%(153/163), with common types followed by ST-T changes[ST-T changes, ST segment changes, Tchange, 36.2%(59/163)], ventricular premature [occasional and frequent ventricular premature, 26.4% (43/163)], complete right bundle branch block [25.8% (42/163)], atrial fibrillation[19.0%(31/163)], and atrioventricular conduction block[8.6%( 14/163)]. X-ray results showed that significant and moderate heart enlargement were common, accounting for 73.4%( 105/143), followed by mild enlargement of 25.2%(36/143). Color doppler ultrasound examination results showed that the atrio-ventricular cavity diameter increased, followed by left ventricular end-systolic diameter increased[81.3%(52/64)], left ventricular end-diastolic diameter increased[65.6%(42/64)], left atrial enlargement[51.6%(33/64)], right atrial enlargement [43.8%(28/64)], and right ventricular enlargement[32.8%(21/64)]. Left ventricular wall and interventricular septum thinning accounted for 15.6%( 10/64) and 7.8%(5/64), respectively. Conclusions In recent years, most cases of chronic Keshan disease occur as natural chronic type, and at older age at onset with low blood pressure.Main clinical features of the disease are cardiac enlargement, inadequate tissue perfusion, and venous stasis performance caused by cardiac decompensation. Correct diagnosis of chronic Keshan disease can be made based on these clinical features.

Objective:To find out the difference between children with attention-deficit/hyperactivity disorder and normal control,and the difference between boys and girls with ADHD in resting-state.Methods:There were 38 children with ADHD in this study including 31 boys and 7 girls,meanwhile,42 normal controls whose age and gen der were matched with children with ADHD were involved too,including 29 boys and 13 girls.Total scores of ADHD rating scale (ADHD-RS) were used to measure the severity of symptom for both ADHD and normal control.Magnetic resonance imaging was used to collect the resting-state functional magnetic resonance imaging data,and the fractional amplitude of low frequency fluctuation (fALFF) was measured for each child.Analysis of covariance (ANCOVA) was used to find out the difference between the group and the sex.Results:Children with ADHD showed a higher fALFF in the right medial superior frontal gyrus and right supplementary motor area,and a lower fALFF in the left putamen,bilateral cerebellum and bilateral precuneus than controls (all corrected P ＜0.05).ADHD boys showed a lower fALFF in the left cerebellum and a higher fALFF in the bilateral medial superior frontal gyrus than boys without ADHD (all corrected P ＜0.05).ADHD girls showed a higher fALFF in the bilateral cerebellum and in the thalamus than girls without ADHD,and a lower fALFF in the insula than girls without ADHD (all corrected P ＜ 0.05).There was a negative relationship between the fALFF of the left cerebellum of ADHD girls and the scores of inattention symptoms.Conclusion:The fALFF difference exist between ADHD and normal controls,and between boys and girls with ADHD.