The article discusses the experiences of five-year minority medical students in internal medicine practice teaching.The content includes cultivating studnts’ ability of clinic thought,the application of casuistics methods,PBL method,combination of teaching and clinic,me-dia mix’s application,improving students’communication ability,adjusting teaching method in time,and so on.The purpose is to improve the effect of minority medical students in internal medicine practice teaching.

Objective To define the significance of the anatomical division and features of popliteal artery in popliteal angioplasty.Methods This study involved 118 lower limbs in 113 cases of femoropoliteal occlusive disease undergoing angioplasty in our center between August 2011 and July 2013.A bent-knee angiogram was taken before recanalization of the lesion.The flexion pattern and the location of flexion points of popliteal artery were collected to study their relationship with the division of popliteal artery.A post-procedural bent-knee angiogram was taken in case of popliteal stenting to assess any change in flexion angulation and distal flow.Results There are diverse flexion patterns in popliteal artery,75.4％ of the flexion points locate in P2 segment,18.6％ in P1,and 6.0％ in P3.On post-procedural bent-knee angiogram in 73 cases of popliteal stenting,10 had a more acute distal flexion angulation,distal artery kinking was observed in another 6 cases of which 5 had compromised distal flow.Artery kinking only occurred in cross-flexion-point stenting.Conclusions A better understanding of the division and anatomical features of popliteal artery can be obtained via bent-knee angiogram.This is of value to angioplasty for lesions in different popliteal divisions.

ObjectiveTo investigate the safety and efficacy of carbon dioxide ( CO2 ) insufflation during ERCP.MethodsBetween January and August 2011,a total of 102 consecutive patients who underwent ERCP were randomized to accept CO2 insufflation ( n =52 ) of air insufflation ( n =50 ) during the procedure.ERCP was carried out with the same instrument by an expert endoscopist who was blinded to the insufflation gas used and the procedure was controlled at 30 minutes to 1 hour.The heart rate,oxygen saturation of the patient was continuously monitored during the procedure.Before the procedure and 1 hour after the end of operation,abdominal X-ray was taken to evaluate the width of intestine,and the degree of intestinal expansion was defined as normal,mild,moderate and severe according to the width increased.A questionnaire with 100 mm visual analogue scale (VAS) was used to quantify the abdominal pain and distention experienced at 1 hour,2 hours,and 6 hours after the procedure.The patients' vital signs,bowel dilatation,the average operating time,abdominal pain score and distention score on VAS,and complications in 2 groups were analyzed.ResultsThe baseline characteristics of 2 groups were comparable.ERCP was successfully performed in all the patients and no complication was observed.In CO2 group,the average operating time,mean heart rate and oxygen saturation were (45.2 ± 10.6) min,( 102.2 ± 10.3 ) bpm and ( 99.5 ± 0.5)％,which were (48.5 ± 11.2) min,( 100.3 ± 11.4) bpm and (98.9 ±0.6)％,respectively,in air group.There were no significant differences on these items between the 2 groups ( P ＞ 0.05 ).Moderate to severe intestinal expansion 1 hour after ERCP was found in 14 patients (26.9％ ) in CO2 group and in 28 patients (56.0％ ) in air group,and the latter was significantly higher than the former (x2 =11.61,P =0.009).Both of the mean abdominal pain and abdominal distention scores at 1 hour post-ERCP in CO2 group were lower than those in air group,but without significant difference (P ＞0.05).However,the mean abdominal pain scores at 2 hours and 6 hours post-ERCP in CO2 group were significantly lower than those of patients in air group (7.4 ±2.2 vs.18.7 ±4.6 at 2 hours post-ERCP,9.6 ±3.7 vs.20.1 ±4.5 at 6 hours post-ERCP,all P ＜ 0.05 ).Similarly,the mean abdominal distention scores at 2 hours and 6 hours post-ERCP in CO2 group were significant lower than those of patients in air group (7.6 ±3.6 vs.18.3 ±4.1 at 2 hours post-ERCP,8.9 ±3.7 vs.19.4 ±4.2 at 6 hours post-ERCP,all P ＜0.05).ConclusionThe use of CO2 insufflation instead of air during ERCP appears to be safe.Insufflation of CO2 during ERCP palliates the intestinal expansion,post-ERCP abdominal pain and distention comparison to insufflation of air.However,because of the single-center clinical observation with limited number of cases,the safety and efficacy of CO2insufflation during ERCP requires to be further evaluated.

Objective: In order to observe the kinds and intensity of the working noise of Yansan Petrochemical Co. and the effects caused by the working noise on the workers＇ vestibular and auditory function. Method :The intensity and frequency of the working noise were recorded by exactolnoisemeter in the workshop. One hundred and seventeen workers were tested in routine pure-tone tested method. The SPVN and ABR were tested within fifty-one workers of all. Result:The working noise of Yansan Petrochemical Co. belongs to the broad band and steady noise. The intensity of the working noise were during 85.7～104.0 dB (A) and the main frequency were during 1～8 kHz. About 59 percent workers who exposed to the working noise had hearing loss. The most hearing-loss were in the high frequency. The hearing-loss of speech frequency were slight. Workers who have more six years standing have obviously increased hearing-loss than the workers who have less five years standing. There were significant differences the ABR thresholds and wave-interval between the tested and controlled groups. The SPVN and CP were abnormal in more than 17.4 percent workers with hearing loss. Conclusion: The working noise of Yansan Petrochemical Co. belongs to the broad band and steady noise. Working noise can lead to workers＇ hearing loss of certain degrees who exposed in the noise for a long time. Obvious correlation was not defined between the hearing-loss and the abnormal vestibular response group.

Nitrate not only remarkably stimulates the rifamycinbiosynthesis in Amycolatopsis mediterranei, but also influences the primary metabolisms, including the inhibition of fatty acids biosynthesis in the bacterial. This phenomenon has been designated as "Nitrate Stimulating Effect" by the late Prof. J.S. Chiaosince its discovery in the 1970's, and has been found in many other antibiotics-producing actinomycetes subsequently. Based on the research in his laboratory, we have revealed that the nitrate stimulation effect mainly manifests in two aspects over the last two decades. First, nitrate promotes the supply of rifamycin precursors, e.g., UDP-glucose, AHBA, malonyl-CoA and methylmalonyl-CoA. Specifically, the biosynthesis of fatty acids is inhibited by nitrate consequently the acetyl-CoA is shunted into malonyl-CoA. Second, nitrate facilitates the expression of genes in the rifclulsterthat encodes rifamycin biosynthetic enzymes. Following our current understanding, the future research will focus on the signals, the signal transduction pathway and the molecular mechanisms that dictate nitrate-mediated transcriptional and post-translational regulations.
Actinomycetales ; classification ; metabolism ; Acyl Coenzyme A ; chemistry ; Anti-Bacterial Agents ; biosynthesis ; Nitrates ; chemistry ; Rifamycins ; biosynthesis

[Objective] To observe the effect of cyclosporine A (CSA) on the activity and expression of MMP-2 and MMP-9 in renal tubular epithelial cells. [Methods] NRK52E cells were cultured until its reached confluent. Then NRK52E cells were exposed to different concentration of CSA (0, 0.42, 0.84, 4.2, and 8.4 μmoL/L) for 48 h or 72 h respectively. MMP-2 and MMP-9 activities were detected by gelatin zymography. The expression of MMP-2 and MMP-9 mRNA were detected by RT-PCR. [Results] MMP-2 activity and mRNA levels were decreased in a dose dependent manner after exposed to different concentration of CSA for 48 h or 72 h in NRK52E cells. Compared with control (CSA 0 μmoL/L), CSA 0.42, 0.84, 4.2, 8.4 μmoL/L decreased the MMP-2 activities to 27%, 24%, 11%, and 9% respectively; The differences are significant, P<0.05. But the MMP-9 activity and mRNA levels were increased after exposed to CSA for 48 h or 72 h in NRK52E cells. Compared with control group, CSA 4.2 μmoL/L exposure increased MMP-9 activity to 438% in 48 h, and 237% in 72 h; the differences are significant as well, P<0.05. [Conclusion] A dose-dependent decrease in the expression and activity of MMP-2, and the up-regulation of the expression and activity of MMP-9 by CSA in renal epithelial cells may related to CSA associated tubulointerstitial damage.

Objective To investigate the function of estrogen in the proliferative and involuting stages of infantile hemangioma. Meothods Expression of estrogen receptor(ER),VEGF and bFGF were detected with SP immunohistochemical method in 42 cases of hemangiomas and 17 cases of vascular malformations.Results The label index(LI) of ER,VEGF and bFGF in the hemangioma was significantly higher than those in the vascular malformation and normal skin(P

AIM: To design,prepare and screen out functional small interfering RNA(siRNA) for specifically silencing proliferating cell nuclear antigen(PCNA) gene expression and effectively inhibiting cell proliferation on human hepatoma cell line SMMC-7721,human gastric carcinoma cell line SGC-7901 and human colorectal carcinoma cell line Caco2.METHODS: PCNA siRNA was designed based on previous studies about design guidelines and synthesized in vitro by T7 Mega short script reaction kit according to the manufacturer's instructions.After purification,the integrities of siRNA were identified through 19% denaturing polyacrylamide gel electrophoresis,and the concentrations of the generated siRNA were measured by testing the absorbance at 260 nm using a spectrophotometer.Four synthesized double-strand siRNA were transfected into three types of carcinoma cell lines by LipofectamineTM2000 reagent,respectively.WST-8 assay was employed to examine the proliferative inhibitions of these three cell lines.The subsequent alterations on PCNA mRNA and protein levels were determined by semi-quantitative reverse transcription-polymerase chain reaction(RT-PCR) and immunocytochemistry,respectively.RESULTS: 3 sequences,No.2,No.3 and No.4 PCNA siRNA showed effective inhibitions on tumor cells among the 4 candidate siRNA,and a single dose of 50 nmol/L of No.2,No.4 PCNA siRNA showed the most effective inhibitory rates as more than 62% at 48 h after transfection.50 nmol/L of No.2 and No.4 PCNA siRNA transfection caused 72% decrease of PCNA mRNA level and almost completely loss of the protein in human Caco2 cells.CONCLUSION: No.2 and No.4 PCNA siRNA have been screened out in this study,which show the capability to effectively down-regulated PCNA expression and significantly inhibit the proliferation of carcinoma cells.The optimal concentration is 50 nmol/L and satisfactory effects are achieved 48 h after transfection in vitro.

Objective To characterize the prevalence of plasmid-mediated quinolone resistance determinants qnrA in extended-spectrum β-lactamase(ESBL)-producing Escherichia coli and Klebsiella pneumonia.Methods PCR was used to amplify qnrA gene in ESBL-rpoducing isolates(including 263isolates of Escherichia coli and 99 isolates of Klebsiella pneumonia).Conjugation experiments and southern blot hybridization were employed to definitude the location of the genes in ZJ96 isolate of Klebsiella pneumonia which had positive qnrA and CTX-M genes.Shot gun sequencing was performed for analyzing the complete nucleotide sequence of pKP96,a plasmid containing qnrA and CTX-M-24 genes in ZJ96 isolate.Results qnrA was detected in 5 out of 263(1.9%)Escherichia coli isolates and 8 out of 99(8.1%)Klebsiella pneumonia isolates.pKP96,a conjugative plasmid including qnrA gene and CTX-M-24 gene presented in ZJ96 isolate.The sequence of the plasmid pKP96 displayed the qnrA,CTX-M-24,aac(6')-Ib-cr,tetA and int Ⅰ 1 genes.Conclusion The plasmid-mediated genes,such as qnrA and CTX-M,may facilitate the prevalence of multi-drug resistant strains.

Objective To evaluate advantages and disadvantages of different pacing modes of cardiac resynchronization therapy (CRT).Methods Twelve dogs with heart failure were performed in every dog at random,and the pacing modes employed in the test included right atrium-different sites of ventricle,and ventricular sites included right ventricular bifocal (RV-Bi),biventricular (Bi-V),left ventricular (LV).The pacing frequency was 180 times per minute,and the results were measured before pacing and after 15 minutes when the pacing became stable in Color Doppler echocardiography,including left ventricular enddiastolic diameter (LVEDd),left ventricular ejection fraction (LVEF),interventricular mechanical delay (IVMD),interventricular septum and left ventricular posterior wall motion delay (SPWMD),left ventricular 12-segment peak time standard deviation (Ts-SD).Results (1)Compared with before pacing,at the RV-Bi,Bi-V,and LV pacing modes,LVEDd,IVMD,SPWMD,and Ts-SD decreased,LVEF increased,the difference was statistically significant [(42.42 ± 3.94) mm vs (34.00 ± 4.07) mm,(34.17 ± 3.95)mm,(33.75 ±4.18)mm; (28.08 ±4.01)mm vs (13.00 ±3.64) mm,(11.95 ±2.54)mm,(12.08 ±3.51) mm; (75.00 ± 10.22)mm vs (51.75 ±9.84) mm,(20.66 ±7.41) mm,(20.75 ±7.56) mm; (25.08±4.16)mm vs (14.91 ± 3.31)mm,(7.50 ±4.24) mm,(7.41 ±3.39)mm;(32.91 ±4.46)mm vs (41.50 ±4.16)mm,(42.00 ±4.63) mm,(42.41 ±4.99)mm,P ＜0.05].(2)Compared with RV-Bi pacing mode,at the Bi-V,LV pacing modes,SPWMD and Ts-SD decreased,the difference was statistically significant(P ＜ 0.05); there was no significant difference among LVEDd,IVMD,and LVEF (P ＞0.05).(3)There was no significant difference in LVEDd,IVMD,SPWMD,Ts-SD and LVEF between LV and Bi-V pacing (P ＞ 0.05).Conclusions The hemodynamic effects of RV-Bi and LV pacing modes were similar to that of Bi-V pacing,and they can be used as CRT biventricular pacing alternative modes; however,the mechanisms of improving ventricular synchronization are not identical in above pacing modes.