In order to probe into the mechanism of low-dose chemotherapeutic agents in the treatment of leukemia, we studied the effects of low concentrations (l-40ng/ml) of daunorubicin (DNR) on proliferation and differentiation of human promyelocytic leukemia cell line (HL-60). 1 ng/ml DNR could inhibit the proliferation of the cells, but no induction of differentiation was found. DNR at more than 5 ng/ml had both cytotoxicity and induction of differentiation. Through the count of survival cells, [3H]TdR and [3H]UR incorporation, cloning efficiency, cell morphology and NBT reduction test, it is concluded that low-dose DNR could have inhibitory and cytotoxic effects on the cells, and its inducing differentiation was not important.

The effects of 1, 25 (OH)2D3 in combination with low-dose chemotherapeutant on the human promyelocytic leukemic cells (HL-60) were investigated. In 4-day-cultured cells, 1, 25 (OH)2D3 and low-dose harringtonine (HH) or daunorubicine (DNR) had synergic effect in inducing differentiation of HL-60 cells, and HH or DNR significantly potentiated the effect of 1, 25 (OH)2D3 in inhibiting the cell proliferation, which were demonstrated by NBT reduction test and [3H]-TdR incorporation, respectively. Cell cycle analysis by flow cytometery revealed that the cells in S phase decreased remarkably and most cells stopped at G0/G1 phase. The results provide a new way for the inducers in treatment of leukemia.

The effect of inhibition of proliferation of a novel human megakaryoblastic leukemia cell line (HIMeg) by two physiological factors, 1.25-dihydroxyvitamin D3 [1,25(OH)2 D3] and 13-cis-retinoic acid (RA), was investigated. At the range of 10-9 - 10-6 mol/L, 1,25(OH)2 D3 and RA showed significant inhibition of proliferation of the megakaryoblastic leukemia cells,which was demonstrated by count of survival cells,incorporation of [3H]-TdR and [3H]-UR, and cloning efficiency. From above, it can further explain the m.echanism of differentiation-inducers and the effect of 1,25(OH)2D3 on myelofibrosis. It is possible for 1,25(OH)2D3 and RA to be used for a new -treatment.

The degree of satisfaction of the curriculum is related not only to the degree of the curriculum but also to the degree of the students' development. With the concept of teaching reform micro system engineering, using the SIMPP analysis of the degree of satisfaction of the curriculum, the relevant factors of the students are studied. The results show that, the learning state, learning objec-tives, and the education level of mother affect the students more easily on the curriculum satisfaction. Research shows, in the present curriculum condition, educators should guide the students to study hard, establish a clear and reasonable learning goal, give the students the introduction and analysis of the curriculum, can effectively improve the students on the curriculum satisfaction, enhance the enthusiasm of the study.

The influence extent of students from teachers is related to the teaching effect , which means whether it can successfully promote the study of students and reach the expected teach-ing goal during the teaching process. To have a good teaching effect, guided by the micro-system en-gineering of teaching reform, we used SIMPP to analyze the related factors of the influence of students extent from teachers during the teaching process in TCM colleges and universities. The result shows that the influence extent from teachers is related to not only teachers themselves but students and their self-condition and family backgrounds as well. Going further in researching these factors and the related behavior patterns of influence extent of students from teachers is helpful to making the teach-ing more effective and more targeted.

Medical Higher Mathematics,an important fundamental course,is important to improve the students' ability of innovation.According to the characteristics of the students at medical school,and considering the content abstract and the problems difficult to learn and understand,a new teaching model which can focus on absorbing some contents of Pharmacokinetics into Medical Higher Mathematics is dis cussed.At the same time the article discusses how to combine the both courses in three aspects:professional features,the background of the student's knowledge,and teaching method.

ObjectiveTo investigate the effort of MHA-bBMP implantation combined with limited contacted titanium net duct fixation on femoral shaft bone defect of rabbit.Methods48 rabbits were divided into the experimental group (treated with bionic bone MHA-bBMP plus titanium net duck) and control group (treated with iliac autograft plus titanium net duct) with 24 animals in each group. The rabbit femoral shaft bone defect model was established by cutting 10 mm bone fragment off. After operation, bionic bone MHA-bBMP/iliac autograft was implanted into bone defect area and fixed with limited contacted titanium net duck. The general condition, serum alkaline phosphatase, X-ray, histopathologic examination and electron microscope were performed.ResultsThe fixation stability of titanium net duck in two groups was good. The bone defect of two groups was repaired. The results of phosphatase, X-ray, histopathologic examination and electron microscope of two groups were not significantly different.ConclusionBionic bone MHA-bBMP is a high bioactivity substitute, and can obtain therapeutic effect equal to iliac autograft when repairing rabbit's femoral shaft defect.

Objective:To establish a method of multi-PCR to amplify the complete DNA sequence (CDS) of TCR ? and ? chain of the antigen-specific T lymphocytes in local pathologic specimen of active pulmonary tuberculosis patients, and to analyze ?/? T cell receptor gene rearrangement and CDR3 repertoire.Methods:The lymphocytes in bronchoalveolar lavage (BAL) of active pulmonary tuberculosis patients were separated. Following total RNA extraction, cDNA synthesis, Multi-PCR, recombinant clones construction, and sequencing, the CDS of TCR ? and ? chains from these lymphocytes were analyzed by using software of DNAstar and internet TCR resources.Results:24 of ? chain CDS and 13 of ? chain CDS from 3 samples of BAL were obtained. As for TCR ? chain, AV1S2 (54%), AV12S3 (41%), and AV12S2(5%) appeared frequently. BV2(38%), BV29S1(46%), BV14(3%), and BV4S2(3%) in TCR ? chain appeared more often. There were CDR3 diversities between samples and even in the same sample by amino acid sequence analysis, but there were a few identical or similar amino acid sequences. There was the same amino acid sequence of SVGTGTLHQETQY in CDR3 region of ? chain of BAL sample No.1 and No.2; The sequence of AVRDWAGNMLT appeared in two ? chains of BAL sample No.2 and No.3; Moreover, the sequence of AV…DNN…RLM appeared in ? chains of BAL sample No.2 and No.3.Conclusion:A method of Multi-PCR is used to amplify TCR ? and ? chain CDS of tuberculosis patients. There are characteristic T cell clones to proliferate,with TCR ? and ? chain repertiore skewing in local infective focus. The sequences of CDR3 in different TCR clones are mostly different but there are a few identical or similar sequences in the same patient or even between different patients. The identical amino acid sequences of CDR3 are possibly specific for recognizing MTB polypeptide.

Objective To analyse the characteristics of orbital benign and malignant masses on diffusion weighted imaging in combination with conventional MR imaging and evaluate the diagnostic value of apparent diffusion coefficient in distinguishing benign and malignant orbital lesions.Methods Seventy- seven cases with orbital masses,including fifty-five benign lesions and twenty-two malignant tumors,who underwent conventional MRI and diffusion imaging scanning were studied with use of a 1.5 T magnetic resonance system.Quantitative ADC measurements of masses(ADC_M)and of the white matter of eontralateral temporal lobe(ADC_W)were made with two different b-values of 0 and 1000 s/mm~2.The ADC ratio(ADCR)of the lesion to the control was calculated.The receiver operating characteristic curves(ROC) were constructed using various cut points of ADC_M and ADCR for different parameters to differentiate between benign and malignant masses.The area under the ROC curve for each parameter was also calculated. Results All cases were proved by histopathology.The mean ADC_M and ADCR of benign orbital masses were(1.56?0.75)?10~(-3)mm~2/s and 1.85?0.91,respectively.The mean ADC_M and ADCR of malignant orbital masses were(1.09?0.42)?10~(-3)mm~2/s and 1.28?0.53,respectively.There were significant difference both between ADC_M and ADCR of benign and malignant masses(t=2.803,2.735,P

BACKGROUND:In early experiments, we prepared hydroxyapatite-coated mechanical heart valve embedded with col agen using impulse laser sediment method.
OBJECTIVE:To further analyze the histocompatibility and toxicity of hydroxyapatite-coated mechanical heart valve embedded with col agen.
METHODS:After passage, canine vascular endothelial cellsuspension was inoculated onto the hydroxyapatite-coated mechanical heart valve embedded with col agen. One group was inoculated in 5%CO2, 37 ℃ incubator for 3 weeks static culture, and the other group was inoculated in 5%CO 2 , 37 ℃ incubator for 3 weeks spinner culture. Scanning electron microscope was used to observe cellattachment on the material. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to the proliferative capacity of vascular endothelial cells cultured with the hydroxyapatite-coated mechanical heart valve embedded with col agen.
RESULTS AND CONCLUSION:During the spinner culture, adherent cells were found on the surface of mechanical heart valve, and the cells distributed evenly and confluent at 21 days to cover the surface of the material. The number of adherent cells in the spinner culture was higher than that in the static culture. The cells during the static culture were aggregated and distributed irregularly. The mechanical heart valve exhibited no effects on the proliferation of canine vascular endothelial cells which grew wel . These findings indicate that the hydroxyapatite-coated mechanical heart valve embedded with col agen exert no effect on proliferation of vascular endothelial cells, has no toxicity and has good biocompatibility.