Biomedical subjects

Y Sun

Publications and source records attributed to Y Sun.

At least 649 records · Page 36Linked to original sources

PubMed1997

[Anatomy of the cartilages of the nose with secondary deformity associated with unilateral cleft lip].

To explore the influence of displacement and hypoplasia of nasal cartilages to cleft lip nose, 38 patients with secondary cleft lip nasal deformity were randomly chosen. Measurement of length and width of the nasal cartilages was made, and places of them were inspected. The displacement of the cartilages was found in each nose, and hypoplasia of cartilages was in those noses whose deformities were more severe. The conclusion is that both displacement and hypoplasia of nasal cartilages are causing factors of nasal deformity.

Adolescent↗

PubMed1997

[Anatomy of the nasal cartilages of the unilateral lip and palate cleft nose].

Noses of 6 stillborn infants with unilateral lip and complete palate cleft were dissected and analysed. The surgical dissection revealed that the lower lateral cartilages are asymmetrical on both sides, indicating displacement of the lower lateral cartilages and the cartilageous septum which deviates to the normal side. Paired T Test shown that there is no significant difference between two sides in length and width. The conclusion is that the nasal deformities of the lip and palate cleft are congenital and one of the major causal factors is the displacement of lower lateral cartilages and cartilageous septum in the cleft side.

Abnormalities, Multiple↗

PubMed1997

[Long-term results of small cell lung cancer treated by surgery combined with postoperative chemotherapy: a report of 65 patients].

OBJECTIVE: To analyse the long term results of small cell lung cancer (SCLC) treated by surgery combined with postoperative chemotherapy. METHODS: From 1983 to 1994, 65 patients with SCLC were treated by surgery combined with postoperative chemotherapy, and 22 of them received prophylactic cranial irradiation. RESULTS: In 64 evaluable patients, the overall 1-, 3- and 5-year survival rates were 87.5%, 53.2% and 36.3%. Patients treated by radical operation plus chemotherapy gave 1-, 3- and 5-year survival rates of 92.5%, 58.5% and 43.8%. The prognostic surviving factors as analysed showed that statistical differences were observed between stage I and II, I and III A (P < 0.03), N0 and N1 (P < 0.021) in 3-year survival rate, between 2-3 and 4-6 cycle chemotherapy in 1-year survival rate (P < 0.007). CONCLUSION: Surgery combined with postoperative chemotherapy and radiotherapy is preferred for stages I and II, N0 and N1 lesions of SCLC.

Adult↗

PubMed1997

[Development of quality of life questionnaire for Chinese cancer patients receiving chemobiotherapy].

OBJECTIVE: To develop the quality of life questionnaire for Chinese cancer patients receiving chemobiotherapy (QLQ-CCC), and to study the methodology involved in the construction of scales measuring quality of life of cancer patients. METHODS: From April, 1993 to April, 1995, QLQ-CCC had been developed mainly according to the Rolls-Royce model: 30 items were iuitially identified and tested in advance, from which the "best" items were selected to from the final format of QLQ-CCC (the fourth-generation questionnaire) including 35 questions. RESULTS: QLQ-CCC had 35 items mainly concerning the five different aspects of cancer patients. Physical aspect included 16 items, of which 9 were disease/treatment-related (specific items), and 7 non-specific items. Psychological/spiritual, social and general health aspects had 5, 5 and 9 items, respectively. CONCLUSION: Quality of life (QOL) research in cancer patients is conducted primarily through the development, implementation and assessment of QOL scales. QOL scales adopted in the developed countries, owing to difference in sociocultural background, have to be modified according to China's concrete condition. This study is an attempt to set up our own QOL scales for cancer patients.

China↗

PubMed1997

[Detection of Epstein-Barr virus in lymphoproliferative diseases by in situ hybridization].

OBJECTIVE: To study the relationship between Epstein-Barr virus and various lymphoproliferative diseases in China. METHODS: Tissues from 214 patients with lymphoproliferative diseases were examined for the presence of Epstein-Barr virus (EBV) using in situ hybridization with EBV's LMP gene as probe. RESULTS: The positive rate of EBV in Hodgkin's disease(HD), Non-Hodgkin's Lymphoma(NHL), benign lymphoid proliferative disease(BLP) was 30.0%(15/50), 14.0%(18/129), 2.9%(1/35), respectively. Among NHL, EBV was detected in 28.1%(9/32) of high grade lymphoma (HNHL), 10.5%(9/84) of medium grade lymphoma(MNHL) and in none(0/9) of low grade lymphoma(LNHL). Significantly higher rates than that of BLP were observed in HD and HNHL. No significant differences in rates among patients with MNHL, LNHL and BLP. CONCLUSION: EBV may be involved in the pathogenesis of HD and HNHL, but not in MNHL and LNHL.

Adult↗

PubMed1997

[New digital carotid compressor].

Since 1979, many cases of paraganliomas in the neck have been successfully treated in Tianjin Cancer Hospital. All patients who would be subjected to this operation should undergo preoperative compressing exercises of the carotid artery to promote better circulation of collateral cerebral crossflow. Therefore, a reliable and compact instrument is necessary for the compressing exercises of the carotid artery and the long-term ambulatory monitoring of the compressing effect. This paper introduces our developed instrument, Adjustable and Digital Carotid compressor, which is based on the principle of volume-oscillometric method. During the gradual change in cuff pressure, the amplitude of consecutive arterial volume pulsation associated with pulse pressure shows change characteristically due to the nonlinearity of arterial pressure-volume (P-V) relation. Arterial pressure can be determined by detecting this change in the amplitude, while the arterial volume change can be noninvasively obtained as a function of this transmural pressure, provided that the state of blood flow are determined during this pressure measurement. Considering the simplicity and practicability of this instrument, we have designed a new portable one which consists of pulse pressure transducer, signal amplifier, peak voltage locking circuit and liquid crystal displayer. The validity and accuracy of this instrument and a few examples of its clinical application are presented.

Blood Pressure↗

PubMed1997

[The biological effects of recombinant human osteogenic protein-1 to cultured pulp cells].

The study was to observe the biological effects of rhOP-1 on the proliferation, ALPase activity and osteocalcin of dental pulp cells by cell culture technique, MTT, enzyme kinetic methods and radioimmunoassay. The results indicated rhOP-1 could obviously promote the proliferation and enhanced ALPase activity and osteocalcin secretion of pulp cells with showing dose-dependent relationship in this experimental dose range. Thus, rhOP-1 can induce dental pulp cells to differentiate the cells expressing osteoblast phenotype.

Alkaline Phosphatase↗

PubMed1997

Integrated regulation in response to simulated weightlessness.

To investigate physiological effects of tail suspension, Ca2+ concentration, immune factors, erythrocyte rheological properties, and growth hormone were determined in rats suspended for 15 and 30 d. The results showed that inhibitory changes of both local factors (proteins secreted by bone cell, Ca(2+)-ATPase in sarcoplasmic reticium) and integrated regulative factors (immune factor, growth hormone) were observed simultaneously with the decrease of bone mineral content, calcium transportation in skeletal muscles as well as erythrocyte deformability. It suggests that both local and integrated regulative processes are functioning in response to the effects of weightlessness.

Animals↗

PubMed1997

[Variation in hepatitis C virus NS 5b nucleotide sequence and its relationship with interferon treatment].

In order to investigate variation in hepatitis C virus (HCV) nonstructural 5b (NS5b) nucleotide sequence and the relationship with interferon treatment, cDNA containing in this region were obtained by reverse transcription-polymerase chain reaction from the sera of 4 HCV RNA positive asymptomatic chronic carriers and 9 chronic hepatitis C patients. The cDNA were then directly analysed by polymerase-chain-reaction-directed sequencing. Compared with three published HCV type II/1b sequences (HCV-J, HC-C2 and HCV-BDS), the homology of HCV was lower in the patients with chronic hepatitis C (93.52% +/- 2.09% average), especially in nonresponders to interferon (92.70 +/- 1.90% average), than in asymptomatic HCV carriers (95.65 +/- 2.61%). In 5 patients, HCV RNA was eliminated by interferon treatment. In the remaining 4 interferon-treated HCV survived patients there were 9-48 nucleotide substitutions in HCV mutants out of 380 nucleotides, resulting 6-20 amino acids changes out of 126 amino acids. These results suggested that NS5b region variants play an important role in maintaining persistent infection and the evolution of NS5b is associated with the effect of interferon treatment.

Adult↗

PubMed1997

[The carcinogenesis of human cytomegalovirus to mouse cervix].

We plugged the gelfoam impregnated with virus stock solution into mouse cervix with ophthalmic forceps. Mice of Kun-Ming strain were infected with UV-inactivated HCMV (human cytomegalovirus). After 31 weeks, cervical carcinomas were induced in 15% of the infected mice. In another group, infected with UV-inactivated HCMV adding croton oil, the carcinogenesis was 18.8%, but incontrol group, it was 0%. HCMV IE (immediate early) antigen in 12 cancer tissues of UV-inactivated HCMV treated group were all positive, and HCMV IE antibody geometrical average titre in mouse serum of the same group was 1:167.2, but the same two parameters in control group were both negative. The ANAE positive rate of lymphocytes in mouse peripheral blood of UV-inactivated HCMV treated group was 38.9 +/- 6.8%, and of control group was 67.8 +/- 8.0%.

Animals↗

PubMed1997

[A prospective study on transfusion-related hepatitis C virus infection].

64 cases of blood recipients were followed-up for 6 months to study infection of hepatitis C virus. The infection rate of hepatitis C virus was 18.75% in total, including 8 cases of post-transfusion hepatitis C (PT-HC), 1 case of subclinical PT-HC, and 3 cases of anti-HCV sero conversion only. The time of initial ALT abnormality and anti-HCV sero conversion were 28 to 91 (51.9 +/- 20.9) days and 23 to 76 (42.4 +/- 15.9) days after blood transfusion respectively. There were 2 cases with cytomeglovirus infection and another 5 cases with unknown infectious agent were found in this study.

Enzyme-Linked Immunosorbent Assay↗

PubMed1997

[Detection of desmosine in elastin by high performance liquid chromatography (HPLC)].

An assay of desmosine (DES) in elastin hydrolysate was performed by HPLC. Desmosine alone or its mixture with tyrosine and phenylalanine as well as elastin hydrolysate was separated on a C18 column eluted with a mobile phase of MeOH:H2O (2:8, V/V) and detected at UV-280nm. The results showed that the time of DES eluted in all cases mentioned above was comparable. The ratio of peak area (CA) and peak height (CH) between DES and Tyr is 1.4% and 3.4% resectively. It could be as a reliable measure to evaluate the quantity of DES in elastin. The correlation coefficient r was 0.9956 in the range of 0.16-0.64mg/L for a calibration curve of DES concentration vs peak area. In conclusion, this method could be used as a biochemical indication to detect the degradation level of elastin in the pathological state.

Chromatography, High Pressure Liquid↗

PubMed1997

[Optimization of the solvent system in thin-layer chromatography (TLC)].

Much effort in TLC has been devoted to optimization methods of solvent system in order to get best separation of components. Various optimization methods have been established, but the universality of some methods was poor. They were only applicable to samples of known components. This paper reports a complex method. When the complexity of the solvent system was determined, uniform design was used to arrange experiments, the data obtained from scanning chromatogram were input computer to get regression equation. The precision of the regression equation should be judged at first. If the precision was proper, the regression equation could be input the program of the complex method to obtain the composition of the solvent system. Optimization results were dichloroethane-benzene-methanol (4.81:4.42:0.78) for cortical hormone; toluene-ethanol-dichloroethane-trichloromethane (2.30:1.46:3.32:2.92) for sulfa drugs and trichloromethane-methanol-ethyl acetate (3.30:3.29:3.41) for ginkgo biloba. Then the verification experiment was made. The verifying test showed that the experimental results are identical with the calculated ones.

Chloroform↗

PubMed1997

[Preliminary study on planar two-dimensional capillary electrophoresis].

Capillary Electrophoresis (CE) system with rectangular cross section columns is integrated on quartz monocrystal plate. Because of its high surface-to-volume ratio and excellent heat conductivity of quartz, rectangular capillary is extremely efficient in dissipating heat compared to conventional circular capillaries. Comparative study showed that much higher electric field strength can be applied to this system without bubble formation. Another advantage of rectangular geometry channel is better detection ability because of the elimination of optical path distortion. The effectiveness of the planar CE has been demonstrated by comparing the separation of two solutes in phosphate buffer between rectangular and circular cross section column with same area. We also found that the separation efficiency can be improved dramatically by decreasing the channel dimension, which underlies the miniaturization of planar CE. In addition, injection by micro injector eliminate sample biasing and increase reproductivity. A simple manifold of rectangular flow channels are fabricated on quartz substrate. By use of electroosmotic pumping it is possible to control the direction of fluid flow in the manifold of intersecting channels without the use of valves. The experimental results proved that the band dispersion after the valveless switching is almost negligible, showing that the two dimensional separation is possible. The main contribution to band-broadening in our capillary electrophoresis is longitudinal diffusion, injection delay time and wall adsorption. In some cases the wall adsorption make the most contribution. Optimum efficiency depends on minimization of these unavoidable sources causing band broadening.

English Abstract↗

PubMed1997

[Advances in research of hydrophobic interaction chromatographic packings].

Hydrophobic interaction chromatography (HIC) is an attractive method for protein purification. The paper gives a review on the characteristics of HIC packings, including matrices and hydrophobic ligands. The efficiencies for protein separations were compared for different HIC packings. The present situation and the developing trends of the preparative HIC packings were described.

Animals↗

PubMed1997

[Purification and behavior of recombinant human gamma-interferon on reversed-phase high performance liquid chromatography].

A high performance liquid chromatographic system is described for the purification to homogeneity of recombinant human gamma-interferon (gamma-IFN) from the inclusion bodies produced in genetically transformed Escherichia Coli cells. Crude products of gamma-IFN obtained from typical preparative liquid chromatographic separation on Sephacryl S200 column was applied to analytical HPLC with RP-C18 column and eluted with convex gradient of 0-82% acetonitrile in 30 min followed by linear gradient of 82%-100% in 30 min. A constant level of 0.1% trifluoroacetic acid was maintained throughout the gradient process. The retention of gamma-IFN was investigated as a function of pH, temperature as well as concentration of salt in the mobile phase. For denatured and renatured gamma-IFN the chromatographic profiles were analyzed under various conditions. The retention time of renatured gamma-IFN was compared with that of denatured gamma-IFN and a significant difference in the retention time of profiles was observed. Both biological activities were reduced to different degree followed with incorrect disulfide bond gamma-IFN or oligomer gamma-IFN. The purified gamma-IFN has a specific activity about 6 x 10(6) units/mL. The eluats were assayed for identification of gamma-IFN using Enzyme-Linked Immunosorbent Assays (ELISA). Its molecular weight was 17.5 kD, as determined by SDS-PAGE. The results support that renatured sample with tR = 24.8 min and denatured one with tR = 30.1 min were identical protein with different conformation. The chromatographic behavior is explained by the change in net charge and polarity of gamma-IFN when the mobile phase condition and the conformation vary. The oligomer or incorrect disulfide bonds were formed during gamma-IFN renaturation and also the biological activity was found to be native conformation dependent.

Chromatography, High Pressure Liquid↗

PubMed1997

[Analysis of the vol atiles from pigeon's excrement with capillary gas chromatography].

The volatiles from pigeon's excrement were obtained with a simultaneous distillation and extraction (SDE) equipment. The chemical composition of the volatiles was examined by means of capillary gas chromatography and combined gas chromatography-mass spectrometry. Forty seven constitutents of the volatiles were identified by gas chromatography-mass spectrometry. Of these compounds, thirty nine were further identified by measuring their temperature-programmed retention indexes or retention times on OV-1 and PEG-20M columns and making comparison with those of the corresponding authentic samples. The total compounds identified make 57% of the total peak areas. The compound classes consist of alcohols (4), aldehydes (11), ketones(4), acids (8), esters (5), and phenols (2), amounting to 43.68% of the total peak areas. The ten compounds with highest contents are, hexadecanoic acid (9.03%), ethyl acetate (6.85%), ethanol (4.03%), 1-ethoxy-2-methylpropane (3.87%), acetic acid (3.23%), heptadecane-(8)-carbonic acid (3.20%), (Z,Z)-9,12-octadecadienoic acid (3.18%), nonanal (2.85%), 1,2-benzenedicarboxylic, dibutyl ester (2.65%), and acetaldehyde (2.32%). Pigeon's excrement has long been used as a Chinese traditional medicine for the therapeutic treatment of haemorrhoid. Some of the constituents identified in the work have been reported to have antibacterial activities.

Animals↗

PubMed1997

[Capillary gas chromatographic analysis of micro impurities in acrylonitrile].

A megabore SCOT series column of silicone OV-101 and OV-17 for the analysis of micro amount of impurities in acrylonitrile is presented. By using the columns of 50m x 0.53mm i.d. OV-101 and 25m x 0. 53mm i.d. OV-17, with column temperature of 75 degrees C and N2 as carrier gas, u=8cm/s, the main impurities, such as acrolein, acetone and acetonitrile may be well separated from acrylonitrile in 26 min. The results indicate that the series column possesses of high separation efficiency and long column life. The error in quantitative analysis was less than 4%.

English Abstract↗