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Objective:To compare minimally invasive treatment with versus without a 3D printed guide plate for Sanders type Ⅱ calcaneal fractures.Methods:A retrospective analysis was done of the 74 patients with Sanders type Ⅱ displaced intra-articular calcaneal fracture who had been treated at Foot and Ankle Surgery Center, Beijing Tongren Hospital Affiliated to Capital Medical University from January 2018 to January 2020. They were divided into 2 groups according to whether a 3D printed guide plate was used or not. In the 3D printing group of 38 patients treated by minimally invasive surgery assisted by a 3D printed guide plate, there were 22 males and 16 females with an age of (41.5±3.5) years; in the control group of 36 patients treated by traditional minimally invasive surgery, there were 24 males and 12 females with an age of (40.3±7.2) years. The 2 groups were compared in terms of operation time, intraoperative fluoroscopy, American Orthopaedic Foot and Ankle Society (AOFAS) score, visual analog scale (VAS), Short Form 36 (SF-36), B?hler angle, Gissane angle, calcaneal length, width and height and postoperative complications.Results:There was no significant difference in the preoperative demographic data between the 2 groups, indicating comparability between groups ( P>0.05). All patients were available for a follow-up of (12.6±3.6) months (from 6 to 24 months) after surgery. The operation time [(55.3±7.1) min] and intraoperative fluoroscopy [(8.1±2.6) times] in the 3D printing group were significantly less than those in the control group [(71.2±8.7) min and (21.2±8.7) times] ( P<0.01) while the AOFAS score in the former group (81.4±6.3) was significantly higher than that in the latter (77.9±6.2) ( P<0.01). There were no statistically significant differences between the 2 groups in VAS, SF-36, B?hler angle, Gissane angle, calcaneal length, calcaneal width or calcaneus height ( P>0.05). In the control group, 4 screws were found to be too long with possible impingement on the medial structures of the foot, and 3 screws to penetrate the subtalar joint; in the 3D printing group, there were no too long or off-target screws in the sustentaculum tali. Conclusion:The minimally invasive treatment of Sanders type Ⅱ calcaneal fractures assisted by a 3D printing guide plate can reduce operation time, intraoperative fluoroscopy and potential complications, improving the clinical efficacy.
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Objective:To determine the influences of structural changes after valgus impacted femoral neck fracture on hip range of motion (ROM) so as to provide evidence for clinical judgment of whether reduction is necessary or not in the internal fixation of such fractures.Methods:1. 3D reconstructions of the CT hip scans were performed for the 73 patients who had been treated at Department of Orthopaedic Surgery, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University for valgus impacted femoral neck fractures from January 2019 to April 2019.The femoral neck-shaft angle, anteversion angle, femoral offset, axial alpha angle, lateral center edge angle (LCEA), anterior center edge angle (ACEA) and center displacement were measured and compared between the affected and healthy sides to determine the influences of the fracture on the above indexes. 2. Hip motions (flexion and MIR-90°) were simulated on bilateral sides to determine the influences of structural changes after fracture on hip ROM using stepwise regression and Logistic regression. 3. The distribution of femoral-acetabular contact points on the femoral side was observed in simulation of hip flexion to detect the potential area for femoracetabular impingement (FAI) induced by the fracture displacement.Results:1. The valgus impacted femoral neck fractures had significant influences on femoral neck-shaft angle, anteversion angle, femoral offset and axial alpha angle. Compared with the healthy side, on average, the femoral neck-shaft angle increased by 5.1°, anteversion angle decreased by 6.5°, femoral offset decreased by 8.2 mm and axial alpha angle increased by 9.7° on the affected side, showing significant differences ( P<0.05).The displacements of the femoral head center averaged 9.2 mm. There was no significant difference in LCEA or ACEA between the affected and healthy sides ( P>0.05). 2. Compared with the healthy side, on average, the simulated hip flexion decreased significantly by 27.0° and the hip MIR-90° decreased significantly by 20.3° on the affected side after fracture ( P<0.05). Regression analysis showed that femoral anteversion angle, ACEA and displacement of the femoral head center had a significant influence on hip ROM, especially the anteversion angle. When the anteversion angle decreased by more than 7.1°, the hip flexion would decrease by at least 20%. 3. The points of FAI distributed more widely on the fracture side. Compared with the healthy side, the impact points extended outward and upward in hip flexion and extended inwardly in hip MIR-90° on the affected side. Conclusions:After a valgus impacted femoral neck fracture, if the femoral anteversion angle has been decreased by more than 7.1°, the hip ROM can be greatly influenced and the points of FAI can be distributed more widely. Therefore, reduction should be recommended before internal fixation of the fracture.
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Background: Cardiopulmonary resuscitation (CPR) strategies in COVID-19 patients differ from those in patients suffering from cardiogenic cardiac arrest. During CPR, both healthcare and non-healthcare workers who provide resuscitation are at risk of infection. The Working Group for Expert Consensus on Prevention and Cardiopulmonary Resuscitation for Cardiac Arrest in COVID-19 has developed this Chinese Expert Consensus to guide clinical practice of CPR in COVID-19 patients. Main recommendations: 1) A medical team should be assigned to evaluate severe and critical COVID-19 for early monitoring of cardiac-arrest warning signs. 2) Psychological counseling and treatment are highly recommended, since sympathetic and vagal abnormalities induced by psychological stress from the COVID-19 pandemic can induce cardiac arrest. 3) Healthcare workers should wear personal protective equipment (PPE). 4) Mouth-to-mouth ventilation should be avoided on patients suspected of having or diagnosed with COVID-19. 5) Hands-only chest compression and mechanical chest compression are recommended. 6) Tracheal-intubation procedures should be optimized and tracheal-intubation strategies should be implemented early. 7) CPR should be provided for 20-30 min. 8) Various factors should be taken into consideration such as the interests of patients and family members, ethics, transmission risks, and laws and regulations governing infectious disease control. Changes in management: The following changes or modifications to CPR strategy in COVID-19 patients are proposed: 1) Healthcare workers should wear PPE. 2) Hands-only chest compression and mechanical chest compression can be implemented to reduce or avoid the spread of viruses by aerosols. 3) Both the benefits to patients and the risk of infection should be considered. 4) Hhealthcare workers should be fully aware of and trained in CPR strategies and procedures specifically for patients with COVID-19.
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Objective To provide basis for early selection of drug intervention or surgical treatment for premature patent ductus arteriosus(PDA) by a dynamic monitoring of serum N-terminal pro-brain natri-uretic peptide(NT-proBNP)levels with ultrasonic examination,so as to improve the prognosis of premature infants. Methods A total of 108 premature infants with gestational age less than 32 weeks and body weight less than 1. 5 kg,within 24 h of birth were admitted to the Department of NICU,Harbin Children′s Hospital from June 2016 to December 2018. The serum NT-proBNP levels were measured at 3 d,6 d,9 d after birth, and echocardiography was performed at the same time. According to the results of echocardiography and clin-ical symptoms,infants were divided into haemodynamically significant PDA(hsPDA)(n=29),asymptomatic PDA(asPDA)(n=24)and non-PDA as control group(n=55). Among them,the hsPDA group was further divided into drug treatment group(n=21) and surgical treatment group(n=8). The surgical treatment group was those who failed 2 courses of oral ibuprofen treatment or had contraindications to drug treatment. Arterial catheter ligation was used for surgical treatment group on 9 to 21 days after birth. NT-proBNP levels were de-tected at 24 hours and 3 days after surgery,and echocardiography was performed at the same time. The levels of serum NT-proBNP were compared between the three groups and before and after the treatment,and the ROC curve of NT-proBNP was drawn to analyze its diagnostic value. Results (1) At 3 and 6 days after birth,serum NT-proBNP levels were 8 346 pg/ml and 3 340 pg/ml in the hsPDA group,and 2 536 pg/ml and 1 079 pg/ml in the asPDA group,1 132 pg/ml and 879 pg/ml in the control group,respectively. The levels of NT-proBNP in the hsPDA group were significantly higher than those in the asPDA group(P<0. 05),and the levels of NT-proBNP in the asPDA group were higher than those in the control group(P<0. 05). At 9 days after birth,serum NT-proBNP levels were 2 231 pg/ml in the hsPDA group,834 pg/ml in the asPDA group, and 808 pg/ml in the control group. The levels of serum NT-proBNP in the hsPDA group were significantly higher than those in the asPDA group and the control group (P<0. 05). There was no significant difference between the asPDA group and the control group (P>0. 05). (2)At 3,6,and 9 d after birth,serum NT-proBNP levels were 9 000 pg/ml,8 989 pg/ml,9 000 pg/ml in the surgical treatment group, and 3 741 pg/ml, 2 544 pg/ml and 1 032 pg/ml in the drug treatment group,respectively. The levels of serum NT-proBNP in the surgical treatment group were significantly higher than those in the drug treatment group (P<0. 05). The serum NT-proBNP levels in both drug treatment group and surgical treatment group were significantly lower than those before treatment ( P < 0. 05 ). At 3 d after the operation, the serum NT-proBNP level was 941 pg/ml in the surgical treatment group and 736 pg/ml in the drug treatment group. There was no signifi-cant difference between the two groups (P>0. 05). (3)At 3 d after birth,the area under the ROC curve of serum NT-proBNP was 0. 91 (95%CI 0. 865-0. 964),and the sensitivity and specificity of NT-proBNP to diagnose hsPDA at 2 343. 5 pg/ml were 93. 1% and 73. 41.% respectively. Conclusion NT-proBNP level monitoring can be used as a sensitive indicator for early identification of hsPDA,and it has a clinical signifi-cance for intervention strategy and intervention time selection.
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Objective@#To provide basis for early selection of drug intervention or surgical treatment for premature patent ductus arteriosus(PDA) by a dynamic monitoring of serum N-terminal pro-brain natriuretic peptide(NT-proBNP)levels with ultrasonic examination, so as to improve the prognosis of premature infants.@*Methods@#A total of 108 premature infants with gestational age less than 32 weeks and body weight less than 1.5 kg, within 24 h of birth were admitted to the Department of NICU, Harbin Children′s Hospital from June 2016 to December 2018.The serum NT-proBNP levels were measured at 3 d, 6 d, 9 d after birth, and echocardiography was performed at the same time.According to the results of echocardiography and clinical symptoms, infants were divided into haemodynamically significant PDA(hsPDA)(n=29), asymptomatic PDA(asPDA)(n=24)and non-PDA as control group(n=55). Among them, the hsPDA group was further divided into drug treatment group(n=21) and surgical treatment group(n=8). The surgical treatment group was those who failed 2 courses of oral ibuprofen treatment or had contraindications to drug treatment.Arterial catheter ligation was used for surgical treatment group on 9 to 21 days after birth.NT-proBNP levels were detected at 24 hours and 3 days after surgery, and echocardiography was performed at the same time.The levels of serum NT-proBNP were compared between the three groups and before and after the treatment, and the ROC curve of NT-proBNP was drawn to analyze its diagnostic value.@*Results@#(1) At 3 and 6 days after birth, serum NT-proBNP levels were 8 346 pg/ml and 3 340 pg/ml in the hsPDA group, and 2 536 pg/ml and 1 079 pg/ml in the asPDA group, 1 132 pg/ml and 879 pg/ml in the control group, respectively.The levels of NT-proBNP in the hsPDA group were significantly higher than those in the asPDA group(P<0.05), and the levels of NT-proBNP in the asPDA group were higher than those in the control group(P<0.05). At 9 days after birth, serum NT-proBNP levels were 2 231 pg/ml in the hsPDA group, 834 pg/ml in the asPDA group, and 808 pg/ml in the control group.The levels of serum NT-proBNP in the hsPDA group were significantly higher than those in the asPDA group and the control group (P<0.05). There was no significant difference between the asPDA group and the control group (P>0.05). (2)At 3, 6, and 9 d after birth, serum NT-proBNP levels were 9 000 pg/ml, 8 989 pg/ml, 9 000 pg/ml in the surgical treatment group, and 3 741 pg/ml, 2 544 pg/ml and 1 032 pg/ml in the drug treatment group, respectively.The levels of serum NT-proBNP in the surgical treatment group were significantly higher than those in the drug treatment group (P<0.05). The serum NT-proBNP levels in both drug treatment group and surgical treatment group were significantly lower than those before treatment (P<0.05). At 3 d after the operation, the serum NT-proBNP level was 941 pg/ml in the surgical treatment group and 736 pg/ml in the drug treatment group.There was no significant difference between the two groups (P>0.05). (3)At 3 d after birth, the area under the ROC curve of serum NT-proBNP was 0.91 (95%CI 0.865-0.964), and the sensitivity and specificity of NT-proBNP to diagnose hsPDA at 2 343.5 pg/ml were 93.1% and 73.41.% respectively.@*Conclusion@#NT-proBNP level monitoring can be used as a sensitive indicator for early identification of hsPDA, and it has a clinical significance for intervention strategy and intervention time selection.
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Biological pharmaceutics is not only the important basic course in medicine,biotechnology,but also the course of combination of theory and practice.Experiment plays an important role in the teaching system of biological pharmaceutics.According to the characteristics of biopharmaceutical and the demand for talent cultivation,we have made some adjustments from the basic process of genetic engineering drug preparation such as rearranging biopharmaceutical experimental classes to form a systemic experiment content,increasing the experiment lesson,innovatively making the students participant in the experiment preparation,and opening the laboratory and improve the method of experiment examination.It has been proved that this teaching reform can improve the teaching quality of experimental class,and has valuable demonstration significance and reference value to the quality education and experimental teaching reform.
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Objective To study the distribution of intra-articular posterior malleolus fracture lines in ankle fracture of supination-external rotation.Methods Computed tomography scans of a consecutive series of 70 ankle fractures of supination-external rotation were used for this study.The DICOM files were loaded into Mimics 16.0 for 3D reconstruction of distal tibial articular surface.The intra-articular posterior malleolus fracture lines were identified after virtual fracture reduction.All the fracture lines were drawn on one picture of distal tibial articular surface after standardization before a heat map was created based on the frequency of fracture lines.Results Although the distribution of posterior malleolus intra-articular fracture lines varied,most of them were concentrated in an arcuate zone.The ratios of the area of posterior fracture fragment to the total area of articular surface averaged 14.96% (range,from 2.23% to 38.45%).They were most likely to enter the articular surface at 20.4% of the tangent of the posterior edge in a standardized image and exit at 58.7% of the tangent of the lateral edge.Conclusion In ankle fractures of supination-external rotation,most intra-articular posterior malleolus fracture lines may be distributed regularly in an arcuate zone of the articular surface.
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Objective To explore the influence of intravenous injection combined with oral of metoprolol tartrate on left ventricular function and adverse cardiovascular events of patients with acute anterior myocardial infarction.Methods84 cases of Patients with acute anterior myocardial infarction treated in the First Hospital of Hebei Medical University were selected as the study objects, and were divided into vein group and combination group according to drugs-taking modes, 42 cases in each groups.The vein group were treated with intravenous injection of metoprolol tartrate, and the combination group were treated with intravenous injection combined with oral of metoprolol tartrate.Clinical effect, left ventricular function, BP and HR levels, and incidence of adverse cardiovascular events were observed in the two groups.ResultsThe total effective rate of the combination group was 95.24% significantly higher than that of 80.95% in the vein group(P0.05).ConclusionIntravenous injection combined with oral of metoprolol tartrate can effectively improve left ventricular function of patients with acute anterior myocardial infarction, and reduce incidence of adverse cardiovascular events.
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Objective To introduce a self-developed computer-assisted design/rapid prototyping and guidance system used for precise placement of the acetabular component in total hip arthroplasty.Methods We collected the preoperative pelvic CT scanning data of 10 hips with aeetabular dysplasia that had undergone primary total hip arthroplasty from January 2016 to January 2017.The total time for import of radiographic images,model reconstruction,model segmentation,acetabular component position design and STL model export was calculated and compared between our self-designed software and Mimics vl 7.0.Three kinds of STL model from each case were imported into our self-developed 3D printing device,Stratasys Objet30 and Stratasys Demension SST1200es respectively for rapid prototyping.The printing efficiency and accuracy were compared among the 3 printers.The accuracy of placing acetabular component with guidance system was evaluated.Results The average time forpreoperative planningwas7.7±1.3 minbyourself-designedsoftware and 52.5 ± 15.9 min by Mimics v17.0,showing a significant difference (P < 0.001).In morphological point-based comparison for each case,the 3D models exported by the 2 different kinds of software showed an average difference of 0.072 1 ± 0.069 1 mm.The average durations for rapid prototyping by the 3 different printers were 5.3 ± 0.6 h,10.8 ± 0.5 h,and 9.3 ± 0.6 h,respectively,showing significant differences (P < 0.001).The guidance system resulted in precise placement.The locations of the acetabular component achieved by guide-assisted placement were not significantly different from the target ones (P > 0.05).Conelusion Our self-developed preoperative planning software,rapid prototyping device and guidance apparatus for acetabular component placement may lead to good accuracy and high efficiency.
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ObjectiveTo introduce the operative technique of pedicle evolution from isolated perforator to perforator-plus-adipofascial,and investigate its clinical results in venous drainage and safety in distallybased sural flaps.MethodsAfter identifying the proper viable perforators,the whole flap was designed in an eccentric propeller shape,with the perforating vessels corresponding to the pivot point.The proximal larger blade was a fasciocutaneous flap, while the distal smaller blade was a subdermal vascular plexus flap,preserving at least a quarter area of adipofascial tissue around the perforator.From January 2008 to December 2010,we performed distally perforator-adipofascial pedicled sural fasciocutaneous propeller flap in 12 patients,with 180 degrees rotation to cover foot and ankle defects.Postoperatively,flap swelling,survival and functional recovery were evaluated. Results There were 7 posterior tibial artery perforator flaps from the posteromedial and 5 peroneal artery perforator flaps from the posterolateral sural region. The proximal fasciocutaneous flap measured 4 cm × 8 cm-6 cm × 18cm, and the distal cutaneous flaps measured 2 cm × 2cm-4 cm × 4 cm.Flap swelling was noted under grade 2 in 9 cases,grade 3 in 2 cases,and grade 4 in 1case with some distal superficial skin necrosis,which occurred in the largest flap in our series.All flaps survived eventfully.After average 13 months follow up,the wound were cured successfully,and all patients recovered walking and shoe wearing function. ConclusionPedicle evolution by keeping some adipofascial tissue around the pivot perforator, can preserve more venous return routes and relieve flap swelling. This technique should be recommended in perforator pedicled propeller flaps,as it enhances flap safety,and without increasing the difficulty of 180 degrees rotation.
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Objective To construct a recombinant bacillus Calmette-Guérin(BCG) vaccines based on different tandem repeats of MUC1 and GM-CSF, rBCG-MVNTR1/4/8-CSF, and to observe the ability of three recombinant BCG vaccines in the inhibition of breast cancer. Methods After MUC1 variable-number tandem repeats (MVNTR1/4/8) were cloned in a stepwise manner, the E. coli-Mycobacteria shuttle expression vector pDE22-MVNTR1/4/8-CSF were constructed by fusing MVNTR1/4/8 and GM-CSF, and then used to transform competent BCG by electroporation after identification by restriction endonuclease digestion analysis and DNA sequencing. A novel breast cancer vaccines, rBCG-MVNTR1/4/8-CSF was constructed. The expression of fused MVNTR1/4/8-CSF protiens was analyzed by SDS-PAGE and Western blot. The ability of rBCG vaccines inhibiting the growth of breast cancer was observed in hu-PBL-SCID mice. The specific T cell responses in mice were assessed by immunohistochemistry. Results The expression of recombinant MVNTR1/4/8-CSF fusion proteins were detected by SDS-PAGE and Western Blot in rBCG-MVNTR1/4/8-CSF vaccines, respectively. Tumor incidence in mice prophylactic immunized with rBCG-MVNTR4-CSF (37.5%) or rBCG-MVNTR8-CSF (25%) significantly decreased compared with PBS and BCG-pDE22 control ( 100% ) at 42 days after tumor implantation ( P < 0. 05 ). MCF-7 tumor growth inhibition in rBCG- MVNTR4/8-CSF-immunized mice was more significant than that in controls ( P <0. 01 ).The inhibition effect of three rBCG vaccines on breast rumor growth appeared to rise with increase of numbers of the tandem repeats of MUC1. Survival rate was 75% of mice in the rBCG-MVNTR4-CSF-treated group and 87. 5% of mice in the rBCG-MVNTR8-CSF-treated groups at 70 days after tumor implantation; however,survival rate was only 12. 5% in control group( P <0. 05). The CD4-positive and CD8-positive lymphocytes were detected only in rBCG-MVNTR4/8-CSF-immunized mice. Conclusions rBCG-MVNTR4/8-CSF immunization inhibits breast cancer growth in mice.
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BACKGROUND: Previous studies demonstrated that construction of eoexpression plasmid containing multiple genes on the same vector could improve transfection and expression rates.OBJECTIVE: To construct eukaryotic expression plasmid pcDNA3.1 (+)-MUC1 -GM-CSF by human polymorphic epithclial mucin (MUC 1) and granulocyte macrophage colony stimulating factor.(GM-CSF) and to observe expression of recombinant plasmid in COS-7 cells.DESIGN,TIME AND SETTING: Gene recombination design,which was carried out in the Animal Central Laboratory,the Fourth Military University of Chinese PLA from September 2005 to December 2006.MATERIALS: Eukaryotic expression vector pcDNA3.1 (+) was presented by Pro.Taylor-Papadimitriou;pGEM-3zf()-GM-CSF plasmid,COS-7 cells,pUCI 8 vector,and E.coli DH5α were made in the center; female BALB/c mice were provided by Experimental Animal Center of the Fourth Military University of Chinese PLA.METHODS: Signal peptide was synthesized with encoded MUCI gene sections to obtain repeated sequence coneatemer after renaturation.Next,the accepted concatemer was cloned with GM-CSF following enzyme identification and sequencing analysis,and then they were put in eukaryotic expression vector pcDNA3.1(+) to construct eukaryotic coexpression plasmid pcDNA3.1 (+)-MUCI -GM-CSF in order to transform COS-7 cells.MAIN OUTCOME MEASURES: Gene expression was detected by indirect immunofluorescence and enzyme linked immunosorbent assay (ELISA).RESULTS: Enzyme identification and sequencing analysis showed that recombinant plasmid contained a fusion gene encompassing human MUC1 repeated sequence concatemer and GM-CSF; moreover,MUC1 expression was detected in COS-7 cells,while recombinant plasmid could induce the production of anti-GM-CSF antibody.CONCLUSION: The recombination between human MUC1 repeated sequence concatemer and GM-CSF gene successfully constructs eukaryotic coexpression plasmid.
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Neurology is an important clinical course. Because of old teaching contents,laggard teaching mode and single teaching goal,the students can not apply after learning neurology course. The curriculum reform of neurology should be carried out under the teaching thoughts of ‘student-centered and competency-based’,to make creation and development in teaching content,teaching style and teaching mode and so on,so as to complete teaching mission better.
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OBJECTIVE To investigate the in vitro antibacterial effect of Asi-antidiarrheal capsule a Chinese herbal compound on hyperthyroid diarrhea.METHODS It was determined by drug dilution method in test tube to determine Asi-antidiarrhea capsule.The compound positive control drug was diphenoxylate co.We made in vitro antibacterial test with 8 kinds of bacteria respectively.RESULTS Asi-antidiarrhea capsule had powerfully bacteriostatic action on Shigella dysenteriae,Staphylococcus aureus and Streptococcus pneumoniae(MIC31.25 mg/L).But diphenoxylate co contrally was less effective on S.aureus,Str.pneumoniae,Str.pyogenes and Sh.dysenteriae(MIC 0.25 mg/L).CONCLUSIONS Asi-antidiarrhea capsule can be used to hyperthyroid diarrhea.Meanwhile,it has powerfully antibacterial effect.It provides evidence of pharmacodynamics for healing infectious diarrhea in the future.
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Objective To probe the mechanism of anticonvulsant by melatonin from the angle of neurotransmitter.Methods Rat status epilepticus(SE) model was induced by pilocarpine(PILO).?-aminobutyric acid(GABA) content and glutamin acid decarboxylase(GAD)67 mRNA expression was detected at 6,48,72 h,and 7 d in the hippocampus of post-SE rats.The effect of melatonin on these changes was observed.Results GABA content was significantly lower in the hippocampus than in control(P
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<p><b>OBJECTIVE</b>To investigate the possibility of multi-unit ribozymes to purge bone marrow of chronic myelocytic leukemia (CML), its in vitro cleavage ability and the reversal effect on CML cell's malignant phenotype.</p><p><b>METHODS</b>As bcr-abl fusion gene plays an important role in CML pathology, three single-unit ribozymes were designed and synthesized in 44 base pairs near the fusion point, two enzyme cleavage sites on bcr gene and one on abl gene. Multi-unit ribozymes' in vitro transcription and retroviral vector through gene recombination were constructed. Then, its in vitro cleavage ability was tested and the retroviral vector was transfected into K562 cell. Through MTT assay, the incorporation rate of (3)H-TdR, RT-PCR, Southern and Northern blot hybridization, flow cytometry, transmission and scanning electron microscopy were used to study the effect of multi-unit ribozymes on CML cell proliferation, cell structure, cell cycle and the induction of apoptosis.</p><p><b>RESULTS</b>Multi-unit ribozymes had in vitro cleavage efficiency of 70.8%. After the transfection of multi-unit ribozymes retroviral vector into K562 cell, cell proliferation and DNA synthesis were greatly reduced with an inhibition rate of about 50% after 96 hours of transfection. Multi-unit ribozymes could cleave K562 cell's RNA with a reduction rate about one 1 000 th of the original. By flow cytometry (FCM), 18.4% cells underwent apoptosis after 72 hours transfection with most of the cells blocked in the G phase. Here, the ratio in S phase was lowered by 41.9%. Under transmission and scanning electron microscope, compaction of nuclear chromation and apoptosis bodies were observed in the transfected cells.</p><p><b>CONCLUSION</b>Multi-unit ribozymes possess high cleavage ability in vitro. The ribozymes, whose retroviral vector being transfected into CML cell, are able to express a lasting ability to cleave the fusion gene, induce apoptosis, reduce cell proliferation, revert the malignant phenotype. It is possible to make use of multi-unit ribozymes to purge CML bone marrow. Therefore, multi-unit ribozymes may very well be valuable in the gene therapy of CML.</p>
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Humanos , Apoptosis , División Celular , Proteínas de Fusión bcr-abl , Genética , Metabolismo , Células K562 , ARN Catalítico , Metabolismo , FarmacologíaRESUMEN
Aim To express the fusion protein hTNFα -hPgnK5 in E.Coli and to identify its activity. Methods The hTNFα -hPgnK5 gene express vector was constructed and the fusion protein was expressed in E.coli. The activity of fusion protein to inhibit the proliferation of tumor cells or angioendothelial cells in vitro was determined by MTT. Results Fusion protein hTNFα -hPgnK5 possessed immunoactivity in Western blot analysis and could inhibit proliferation of tumor cells or angioendothelial cells in vitro test. Conclusion The hTNFα gene and hPgnk5 gene can be coexpressed in prokaryotic system and expression products can inhibit the proliferation of tumor cells or angioendothelial cells in vitro.
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Objective To investigate the expressions and effects of interleukin-4(IL-4) and its alternative spliced variant(IL-4?2) in patients with atopic asthma.Methods The expressions of IL-4 and IL-4?2 were detected in 10 cases of patients with atopic asthma using a quantitative nested reverse-transcription polymerase chain reaction(RT-PCR) protocol.Result The expression level of IL-4 was higher in the patients with atopic asthma than that of the healthy controls.The median ratio of IL-4 to IL-4?2 was much higher in the patients with atopic asthma compared with that of the healthy controls.Conclusion The relative expression of IL-4 and IL-4?2 may play an important role in the mechanism of the pulmonary pathology in patients with atopic asthma,and may be one of the reason for the functional diversity of Th2 cells in different clinical conditions.
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ObjectiveTo investigate the expression of MUC1 in thyroid cancer and benign thyroid diseases (nodular goiter and adenoma) and its clinical significance. Methods The expression level of MUC1 was examined by immunohistochemical analysis with MUC1 monoclonal antibody in 68 samples of thyroid carcinoma and in 18 samples of benign diseases and 10 normal thyroid tissues. Results Immunohistochemical analysis showed positive expression of MUC1 in 51 out of 68 cases of thyroid cancer, in 4 out of 18 cases of benign thyroid diseases and 1 out of 10 normal control thyroid tissue, with a difference statistically significant between the malignancy and benign and normal control (? 2=17.20,P0.05).Conclusion The over-expression of MUC1 in thyroid cancer may act as diagnostic markers of thyroid carcinoma.
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Purpose The aim is to establish fermentation process of new type recombinant human necrosis factor (nrhTNF)α.Methods The optimized host cell,culture medium and induction time were deternined according to the growth and expression specificity of nrhTNF on test tube and flask shaker. Then fed-batch culture was carried out on 5 L automatic fermentor.Results The expression of nrhTNF in fermentor could keep in a higher level of about 50% of total bacterial proteins when fermented to around A600nm 30,with a fermentation time of 12 h to 13 h.Conclusion A short cycle,high expression and stabilized fermentation process was established.