1.Analysis of factors affecting seven-year-program medical students' choice of supervisors and some suggestions
Chinese Journal of Medical Education Research 2015;14(4):404-407
Two-way choice is the main way for the seven-year-program clinical medical students and postgraduate supervisors.This article analyzes the influence factors and shortages of two-way choice for postgraduate supervisors and seven-year-program clinical medical students.This investigation discovers that the supervisor's abilities of research,teaching and clinical and their personal magnetism are important and key factors.The students' gender,character,hobbies and interests and the familiarity to profession are the secondary factors.The other factors that include employment status,the level of income and the advice of parents and friends also have influence on two-way choice for postgraduate supervisors and seven-year-program clinical medical students.In order to further improve the tow-way choice,the author gives some suggestions,including introducing profession and the scientific researches of supervisors in advance,encouraging the face-to-face communication between students and supervisors,promoting multiple profession choices and giving some aids to the students for choosing the supervisors.
2.Lower extremity deep venous insufficiency and Cockett syndrome.
Guoxiang DONG ; Xuan LI ; Jun ZHAO
Chinese Journal of Practical Surgery 2001;21(5):276-277
Objective This study was To investigate the incidence rate of Cockett syndrome and relationship between Cockett syndrome and varicose veins and deep venous incompetence of the left lower extremities.Methods 73 patients(100 legs) with varicose veins of the lower extremities were investigated by descending deep venography and iliography preoperatively.Results There were 35(47.9%) cases with abnormalities of the left common iliac vein (ALCIV)in all the cases.There were 31 cases with this conditions in the patients with varicose veins of the left or both lower extremity.While in the patients with varicose veins of the only right lower extremity,there were only 4 cases with ALCIV.In contrast,there was a significant difference between groups(χ2=9.8641,P=0.0017).In the patients with ALCIV,14 cases with Ⅲ or Ⅳ grade of deep venous incomptence were found, and only 6 cases with deep venous incompetence in the patients without ALCIV.There was a significant difference(χ2=5.3688,P=0.0205).Conclusion Cockett's syndrome frequently occurs in varicose veins of the left lower extremity.There is a relationship between them.Cockett's syndrome might be one of the causes for the deep venous incompetence of the left leg.
3.Cortical bone trajectory for pedicle screws
Jun XUAN ; Daoliang XU ; Xiangyang WANG
Chinese Journal of Orthopaedics 2016;(1):51-57
Pedicle screw fixation is widely used in spine surgery, which allows 3?dimensional fixation with a more rigid construct and permits a shorter fusion length. However, conventional pedicle screw fixation has some drawbacks, including signifi?cant muscle dissection for the exposure of bone marks. Although percutaneous pedicle screw technique can compensate for above defects, it requires an additional approach for decompression and bone graft insertion. Besides, the percutaneous pedicle screw technique depends on intraoperative multiplanar fluoroscopy, which results in high risk of radiation exposure of the surgeons and patients. Screw loosening is a well?known complication, especially in osteoporosis patients. Several methods can enhance screw stability, for example, modifying screw design and augmenting vertebral bodies with reinforcing materials that can improve the structural capacity of the deteriorated tissue, however, they also have some disadvantages. Although we can enhance bone?screw by modifying screw design, it is not useful in severe osteoporosis patients. At the same time, bone cement can increase pedicle screw axial pullout strength and fatigue resistance, however, it is associated with a number of inherent disadvantages such as its high exothermic polymerizing temperature, toxicity of the monomer, and risk of leakage to the spinal canal. Santoni et al. intro?duced cortical bone trajectory (CBT) for lumbar pedicle screw with a new screw design that is shorter and smaller in diameter which has been proposed to maximize the thread contact with this higher density bone surface. In addition, the CBT technique fol?lows a caudocephalad path sagittally and a laterally directed path in the transverse plane, engaging only cortical bone in the pedi?cle without the involvement of the vertebral body trabecular space. Finally, the screw insertion point of this technique locates around lateral pars, enabling less tissue dissection. Therefore, it can be an alternative approach to enhance screw fixation strength, and it may rescue failed pedicle screw and be used in minimally invasive spine surgery.
4.Alkaloidal constituents of Nauclea officinalis
Weidong XUAN ; Jun BIAN ; Haisheng CHEN
Chinese Traditional and Herbal Drugs 1994;0(02):-
Objective To investigate the alkaloidal constituents of Nauclea officinalis, an anti-inflammatory and antibacterial traditional Chinese herb. Methods The alkaloids were isolated and purified by silica gel, Sephadex LH20, and C-18 ODS column chromatography repeatedly, and their structures were identified by spectral analysis. Results Eleven alkaloids were isolated from the stems of N. officinalis and their structures were identified as angustoline (Ⅰ), 19-O-ethylangustoline (Ⅱ), 3-S-3, 4-dihydroangustoline (Ⅲ), 3-R-3, 4-dihydroangustoline (Ⅳ), naucleamide A (Ⅴ), strictosamide (Ⅵ), vincosamide (Ⅶ), 6′-acetyl-strictosamide (Ⅷ), 2′-acetyl-strictosamide (Ⅸ), pumiloside (Ⅹ), 3-epi-pumiloside (Ⅺ). Conclusion Compounds Ⅰ-Ⅺ are isolated from this plant for the first time.
6.Application of spinal cord stimulation in the treatment of cerebral ischemia
Xiaosheng YANG ; Yi XUAN ; Jin ZHU ; Hongxin GUAN ; Jun ZHONG
International Journal of Cerebrovascular Diseases 2010;18(4):286-290
Since Hosobuchi first found that spinal cord stimulation had the effect of significantly increasing cerebral blood flow (CBF) more than two decades ago, spinal cord stimulation had attracted wide attention in the field of treating cerebral ischemia. A large number of animal and clinical studies have been performed in this field, which make it another research focus following thrombolysis and interventional therapy. This article reviews the research history, mechanisms, and current status of clinical applications of spinal cord stimulation in cerebral ischemia protection.
7.Determination of adenosine in Ligia exotica with ultraviolet spectrophotometry
Weidong XUAN ; Jun BIAN ; Huawu ZENG ; Jing XEAO
Chinese Journal of Marine Drugs 1994;0(01):-
Objective To establish a UV method of determination of adenosine in Ligia exotica. Methods Adenosine was extracted with 37℃ water and separated by TLC silica gel, the absorbance was detected at 260nm with UV spectrophotometry.Results The cabibration curve for adenosion was linear within the range of 1.0~20.0?g?mL -1, r=0.9998 (n=6), the average recovery was 99.3%,RSD=1.9% (n=3). Conclusion The method was simple, convenient and accurate for determination of adenosine in Ligia exotica.
8.Effects of perioperative administration of Rhubarb on acute inflammatory response in patients with gastric cancer
Jun CAI ; Zhengrong XUAN ; Yongping WEI ; Haibo YANG ; Hua WANG
Journal of Integrative Medicine 2005;3(3):195-8
OBJECTIVE: To observe the effect of perioperative administration of rhubarb on the acute inflammatory response in patients with gastric cancer. METHODS: In this prospective, single-blinded, controlled clinical trial, thirty-one patients with gastric cancer operatively treated were randomly divided into two groups, with 14 patients in control group and 17 in study group. Patients in both groups were given an isocaloric and isonitrogenous enteral diet. The enteral diet was started 36 hours after operation, and continued for 6 days. Patients in the study group were fed with rhubarb before operation, and at 1 day and 2 days after operation. Indexes of acute inflammatory response such as serum C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-alpha), and indexes of nutritional status such as serum albumin (ALB), prealbumin (PA) and transferrin (TRF) were measured before operation, and at 1 day, 3 and 7 days after operation. RESULTS: Patients in both groups had acute inflammatory response, and the indexes of nutritional status decreased after operation.IL-6, CRP and TNF-alpha tested at 3 and 7 days after operation were lower in the study group as compared with those in the control group, and the recovery time of gastrointestinal motility such as borborygmus, gas elimination and defecation was shorter in the study group as compared with that in the control group. The indexes of nutritional status showed no significant differences between two groups after operation. CONCLUSION: Rhubarb can positively modulate the acute inflammatory response, promote the recovery of postoperative gastrointestinal motility, and benefit enteral nutrition support in patients who have undergone major operations for gastric cancer.
9.Effects of multiple-trough sampling design and algorithm on the estimation of population and individual pharmacokinetic parameters.
Jing LING ; Li-Xuan QIAN ; Jun-Jie DING ; Zheng JIAO
Acta Pharmaceutica Sinica 2014;49(5):686-694
The purpose of this study is to investigate the effects of multiple-trough sampling design and nonlinear mixed effect modeling (NONMEM) algorithm on the estimation of population and individual pharmacokinetic parameters. Oxcarbazepine and tacrolimus were used as one-compartment and two-compartment model drugs, respectively. Seven sampling designs were investigated using various number of trough concentrations per individual ranging from 1-4. Monte Carlo simulations were performed to produce state-steady trough concentrations. One-compartment model was used to fit simulated data from oxcarbazepine and tacrolimus. The accuracy and precision of the estimated parameters were evaluated using the median prediction error (PE), the median absolute PE and boxplot. The results indicated that trough concentrations could yield reliable estimates of apparent clearance (CL/F). For oxcarbazepine, as the number of trough concentrations per subject increased, the accuracy and precision of CL/F, between-subject variability (BSV) of CL/F and residual variability (RUV) tended to be improved. For tacrolimus, however, although no improvement were observed in the accuracy of CL/F and BSV of CL/F, the PE distribution ranges were significantly narrowed and the RUV estimates were less bias and imprecise. In terms of algorithm, Monte Carlo importance sampling (IMP) and IMP assisted by mode a posteriori estimation (IMPMAP) were consistently better than other methods. Additionally, the sampling design had no significant effects on the individual parameter estimates, which were only depended on the interaction between BSV and RUV in various algorithms. Decreased in BSV and RUV levels can improve the accuracy and precision of the estimation for both population and individual pharmacokinetic parameter estimates.
Algorithms
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Bayes Theorem
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Carbamazepine
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analogs & derivatives
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pharmacokinetics
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Humans
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Immunosuppressive Agents
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pharmacokinetics
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Models, Biological
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Monte Carlo Method
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Nonlinear Dynamics
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Regression Analysis
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Tacrolimus
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pharmacokinetics
10.Comparison study on lung function impairment degree between stage II+ and III.
Gang CHEN ; Guo-Xuan MA ; Yan-Jun LI
Chinese Journal of Industrial Hygiene and Occupational Diseases 2010;28(1):47-48
Adult
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Aged
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Humans
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Male
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Middle Aged
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Pneumoconiosis
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pathology
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physiopathology
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Respiratory Function Tests