Problem-based learning (PBL) has been widely used all around the country.But there are still many misconceptions on the understanding of the PBL teaching in the process of teaching practice,which reduces the PBL teaching effect.For example,it is a misunderstanding to put problems to asking for answers to the questions other than solving the problems and to put case-based learning (CBL) and team-based learning (TBL) to PBL.In this paper,we combined the references with the practice experience to compare PBL with CBL,TBL and flipped instruction in both features and connotations based on the brief discussion of the problem in PBL teaching,to further strengthen the understanding of the PBL teaching.It is only the use of clinical cases to guide students to find the defects of the knowledge required for solving the problem and the process of acquiring the scientific knowledge which is implicit in the problem through the students' autonomous learning that can be called as PBL teaching.

Cirrhotic portal hypertension is associated with both increased intrahepatic vascular resistance and hyperdynamic circulation.These two pathogical changes of portal hypertension can be contributed to the unusually high or unusually low levels of vasodilator in liver and splanchnic organs.Vascular hyporesponsiveness due to reactive oxygen species is also a key factor which accounts for portal hemodynamic abnormalities.Transcription factor nuclear factor E2-related factor 2 (Nrf2),known by its role in anti-oxygenation,can initiate and enhance transcription of antioxidant response element (ARE) when exposure to oxidative stress occures.Related influence on expression of nitric oxide,carbon monoxide and their coenzymes has also been demonstrated for decades.The potential clinical significance will be unfolded if changes of Nrf2 expression,as well as the way modulating Nrf2,are found in cirrhotic portal hypertension.

Objective To explore the feasibility of the hydrogel as a cell carrier for parathyroid cells.Methods Cryopreserved parathyroid cells were recovered and cultured until sufficient,then the cells were digested、centrifuged and pipetted to single-cell suspension.The chitosan solution,crosslinking agents and cell suspension were mixed to hydrogels by some ratio.After that,hydrogels covered by complete medium were incubated at 37 ℃ in constant temperature incubator.Meanwhile,the supernatant were collected for measuring the PTH level every other day and the viability and shape of cells in hydrogels was also evaluated by fluorescopy.Results Parathyroid cells were recovered and cultured successfully and the adherent cells were spindle-like.The hydrogel could be prepared at room temperature in less than 1 minutes.The fluorescent confocal microscopy showed that more than 90％ of the cells in the hydrogel kept viable after 24 hours and the proportion had no significant change after 3 days.Furthermore,PTH was detected in the supernatants.Conclusion The facilely prepared inexpensive hydrogel,which can maintain normal morphlology and function of cells,is of potential application to cell transplantation therapy for hypopatathyroidism.

Objective To investigate the accuracy of contrast enhanced ultrasound (CEUS) in diagnosing acute severe panereatitis.Methods Thirty three patients with acute severe pancreatitis were enrolled in the study and all of them underwent CEUS and spiral computed tomography(CT) scan.CT was taken as gold standard in acute severe pancreatitis diagnosis.CEUS were done within 72 hours after CT scan.Results Compared with CT, the sensitivity, specificity,accuracy, positive predictive value,and negative predictive value of CEUS for detecting the necrosis of pancreas were 90%, 95%, 94%, 90% and 95%respectively.The sensitivity, specificity, accuracy, positive predictive value,and negative predictive value of CEUS in diagnosing severe acute pancreatitis were 85%, 92%, 88%, 94% and 80% respectively, while 37% ,86% ,58%, 78%, 50% for conventional ultrasound respectively.Conclusions CEUS is accurate in detection of pancreatic necrosis and diagnosis of acute severe pancreatitis.

Objective To calculate effective dose based on the dose-area Product (DAP) measured in dental cone beam computed tomograhic (CBCT) scanning and using a conversion coefficient.Methods The method of the DAP was used to calculate the effective dose from KODAK 9500 dental CBCT scanner with fields of view (FOV) of 16 cm×15 cm and 12 cmu×8 cm.The DAP-values (mGy · cm2) were measured using a transmission ionization chamber connected to an electrometer (Doseguard 100,RTI Electronics AB,Sweden) and the chamber was placed directly on the exit of the X-ray tube.All measurements were repeated three times and averaged on each FOV data.The conversion coefficient of 0.080 μSv/mGy · cm2 was used to estimate the effective dose on the basis of DAP values,which was quoted from a literature.Results DAP values were found between the two FAOs to vary from 512 to 1 083 mGy · cm2,and the effective doses calculated with 0.080 μSv/mGy · cm2were 41 to 87 μSv.The effective doses given in this paper was lower than those reported in other literatures.Conclusions DAP measurement was found to be well defined and easy-to-use method of determining effective dose for some CBCT Units.However,determination of specific conversion coefficient in the CBCT must be further developed.

ObjectiveTo study the feasibility and effect of microendoscopic discectomy on the central type of enormous intervertebral disc herniation.MethodsFrom 2003 to 2006,23 patients(18 males,5 females) were diagnosed with enormous central type lumbar disc herniation and treated by microendoscopic discectomy.Their clinical data were restropectively analyzed,and postoperative outcomes in hip function were evaluated by Macnab scoring system.ResultsBeing followed up for 3-12 months,21(86.9%) patients were rated as good or excellent for their outcome,and the other two as fair.ConclusionMicroendoscopic discectomy through interlaminar approach achieves satisfied outcome for enormous central type lumbar disc herniation.

Objective: To analyze the genetic relationship among the medicinal plants of Potentilla L. Methods: Six species of germplasm resources in Potentilla L. were analyzed by ISSR molecular markers. To make up the systematic diagram of genetic relationship by Popgene 1.32 software, cluster by UPGMA method, and establish the dendrogram. Results: A total of 105 ISSR bands were scored for 11 primers, among which 89 were polymorphic bands. The average percentage of polymorphic bands was 84.76%. Genetic similarity coefficient changed from 0.4476 to 0.7905. Conclusion: By cluster analysis, it shows that some of the medicinal plants in Potentilla L. from the same region are in the same group and demonstrates the rule of geographical distribution in the tested materials. This study will provide the foundation for identification and development of medicinal plants in Potentilla L., and guide collection and evaluation of germplasm resources.

OBJECTIVE: To investigate the influence of allergic rhinitis on negative emotion. METHOD: One hundred and ninety cases with allergic rhinitis as observer group were investigated by state-trait anxiety inventory (STAI) and self-rating depressive scale (SDS). According to pathogenetic condition, patients were divided into persistent allergic rhinitis 71 cases (A group) and intermittent allergic rhinitis 119 cases (B group). Meanwhile, 190 healthy persons as control group were compared with observer group. RESULT: (1) The main allergens of allergic rhinitis were dermatophagoides pteronyssinus, dermatophagoides farina, pollen, and epiphyte, which the skin index was above "++" by skin prick test. (2) The state anxiety score of observer group (42.17±16.21) was significantly higher than control group (38.78±16.54), t=2.02, P<0.05. There were no difference in trait anxiety between observer group and control group (41.25±16.16 vs. 41.19±16.84), P>0.05. The anxiety scores of female in A and B groups were higher than that of female in control group (43.77±15.76, 42.93±15.58 vs 38.44±15.71), P<0.05. (3) The score of SDS in A and B group was significantly higher than that of control group (37.78±9.22, 39.65±9.87 vs 35.24±7.81), P<0.01. The rate of depression in observer group (11.6%, 22/190) was significantly higher than that of control group (2.6%, 5/190), Χ2=11.52, P<0.01. CONCLUSION The allergic rhinitis may cause patients anxiety and depression, especially for female, but patients with allergic rhinitis have no significant trait anxiety.
Allergens ; Animals ; Anxiety ; complications ; Case-Control Studies ; Depression ; complications ; Female ; Humans ; Male ; Personality Inventory ; Phenotype ; Pyroglyphidae ; Rhinitis, Allergic ; psychology ; Skin Tests

Objective To review the preliminary experience on managing the patients suffering from lumbar disc herniation with lateral recess stenosis by microedoscopic discectomy.Methods A total of 79 patients affected with lumbar disc herniation with lateral recess stenosis were treated by MEDⅡ in our hospital from Jan 2002 to Sep 2004.Results All patients were discharged within 7 d postoperatively and no complications occurred.The average duration of follow-up was 12.3 months and the successful clinical outcome was 99%.Conclusion Microendoscopic discectomy is a minimum invasive procedure.The successful clinical outcome could be achieved in properly selected patients.The microendoscopic discectomy is an effective procedure in managing lumbar intervertebral disc herniation with lateral recess stenosis.

Objective To study the effects and clinical significance of plasma thromboxane B2(TXB2), platelet alpha granule membrance protein-140(GMP-140), 6-Keto-PGF1?(6-K-PGF1?), endothelins(ET), tissue type plasminogen activator(tPA) and plaminogen activator inhibitor-1(PAI-1) in patients with cerebral arteriosclerisis and cerebral thrombosis. Methods Plasma TXB2 ,GMP-140,6-K-PGFla and ET levels were determined by ra-dioimmuno-assay. Plasma tPA and PA1 were determined by the chromogenic peptide substrate method in controls and in patients with cerebral arteriosclerisis and cerebral thrombosis. Results The levels of plasma TXB2 and GMP-140 were significantly higher in patients with cerebral arteriosclerisis and cerebral thrombosis than in the control group(P0.05) .The levels of tPA and tPA/PAI were significantly lower in patients with cerebral arteriosclerisis and cerebral thrombosis than in controls. Although the PAI level increased in patients with cerebral arteriosclerisis and cerebral thrombosis,no difference was found in statistics. Conclusions Activation of platelets, injury of endothelial cell and decreased activity of fibrinolysis in patients with cerebrovascular disease may be involved in the development of these diseases. Appropriate treatment should be adopted on the above abnormality.