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Biomedical subjects

B Wang

Publications and source records attributed to B Wang.

At least 451 records · Page 25Linked to original sources
PubMed1999

[Determination of gallic acid in garden burnet by HPLC].

OBJECTIVE: To establish a HPLC method for the determination of gallic acid in garden burnet. METHOD: The sample was extracted with methanol under ultrasonic management for 25 min. Chromatographic conditions: Shimadzu LC-6A with SPD-6AV detector at 270 nm and auto injector SIL-6A, methanol-0.025 mol/L phosphoric acid(15:85) as the mobile phase. Shin-pack CLC-ODS column(6.0 mm x 15 mm). RESULT: Gallic acid in garden burnet was baseline separated and determined. The average content was 0.22%, recovery rate 97.4% and relative standard deviation 1.3%. CONCLUSION: Simple, rapid and accurate, the method provides new indexes for quality control of Garden Burnet.

Chromatography, High Pressure Liquid↗
PubMed1999

[Isolation, purification and antibacterial activities of salivary histidine-rich polypeptides].

OBJECTIVE: To isolate and purify salivary histidine-rich-polypeptides (HRPs) and observe their antibacterial activities. METHODS: By using of preparative acid urea polyacrylamide gel electrophoresis (AU-PAGE), three major HRPs(HRP-1, HRP-3 and HRP-5) were purified from parotid saliva collected from healthy adults. Their antibacterial activities were tested in the ultrasensitive antibacterial assay, named radial diffusion assay. RESULTS: Each fraction of the three purified HRPs appeared as a single protein zone both in AU-PAGE and Tricine-SDS-PAGE. Their molecular weights are 3-5 kD as determined by Tricine-SDS-PAGE. All the three major HRPs showed potent bactericidal effects on Streptococcus mutans MT6R and Staphylococcus aureas ATCC25923. As to Escherichia coli ML-35P and Pseudomonas aeruginosa ATCC27853, HRP-3 and HRP-5 also demonstrated significant antibacterial activities, whereas HRP-1 did not show any inhibitory effects on the viability of them. CONCLUSION: The above results suggested that the method of preparative AU-PAGE we used in this study has the benefits of high resolution, simple manipulation and perfect results of purification. HRPs are important components to prevent oral tissue from bacterial infections, therefore play a potent role in the maintenance of the oral health.

Adult↗
PubMed1999

[A comparative study of mechanical properties of microwave-cured and conventional water bath-cured denture base resins].

OBJECTIVE: To study the mechanical properties of microwave-cured polymethyl methacrylate (PMMA) denture base resins. METHODS: Using experiment research, the mechanical properties of microwave-cured and water bath-cured PMMA materials were compared. RESULTS: The microwave-cured acrylic strips had equal or better mechanical properties than conventionally processed strips. CONCLUSION: The microwave-cured denture materials satisfies the requirements of the prosthetic clinic.

Biomechanical Phenomena↗
PubMed1999

[Studies on degradation of poly-(propyl,3-hydroxypropyl)-DL-asparamide and release of conjugate linking aspirin in vivo and in vitro].

Two polyasparamide derivants having different hydrophilicities were selected to be degraded in vivo and in vitro. The results demonstrate that the degradation process of polyasparamide is enzymatic hydrolysis. Materials with different hydrophobicities are different in degradation rate and the same material has different metabolic rates in the planting position, kidney and liver. The release results of two polymeric drugs indicate that protease is of advantage to release of drug, and hydrophobicity of material is also an advantage to the release.

Animals↗
PubMed1999

[A water-soluble synthetic polymer, alpha,beta-poly(hydroxyalkyl)-DL-asparamide, and conjugating drug].

A water-soluble polymer alpha,beta-poly (hydroxyalkyl)-DL-asparamide was synthesized by polysuccinimide(PSI) and different lengths of hydroxyalkyls, including alpha,beta-poly(hydroxyethyl)-DL-asparamide(PHEA), alpha,beta-poly(hydroxypropyl)-DL-asparamide(PHPA), and alpha,beta-poly(hydroxybutyl)-DL-asparamide(PHBA). These polymers were characterized by differential scanning calorimetry(DSC) and infrared spectrophotometry(IR). Stability and acutetoxicity of these polymers were studied. The experiment indicated that these materials were of low-toxicity and high stability. Acetylsalicylic acid, as a model drug, was conjugated into polymers; the drug loadings were 38.63%, 37.68% and 38.70% respectively. Polymer drugs were made into cylinder, and in-vivo release in rabbits was set out. It showed that the longer the spacer was linked into the polymer, the faster the drug was released.

Animals↗
PubMed1999

[Safety analysis of dust mite allergen for diagnosis and immunotherapy of asthma and rhinitis].

AIM: To make a retrieval investigation of safety in using Dermatophagoides farinae extract in diagnosis and immunotherapy with patients of asthma and rhinitis. METHODS: A questionnaire evaluation of the safety use of D. farinae extract (SMU-Df) during diagnosis and immunotherapy of patients from 1974 to 1995 was carried out. RESULTS: A total of 8,46,342 injections were statistically analysed, among whom 142 systemic adverse reactions occurred involving urticaria 0.82@10000, severe attack of asthma 0.77@10000, anaphylactic shock 0.07@10000 (CL = 1.4-12.0/million), and angioedma 0.02@10000. The time of onset of systemic reactions of immediate type was < 30 min in 32 cases-times, and 1 h and 2 h in 6 cases-times; the time to onset of late response type was 3 h-48 h in 23 cases-times with highest incidence of severe asthmatic attacks. The systemic reactions occurred in 18 subjects during skin test, in 96 cases-times during increasing dose phase, and in 14 cases-times during. Among them 6 cases were of anaphylactic shock, and none of it after emergency treatment. The major cause of manifestation of systemic reactions for 41 cases after immunotherapy with SMU-Df extract was due to over dosage errors. CONCLUSION: The application of SMU-Df extract in skin test and immunotherapy of asthma and rhinitis sensitive to mite for the past 22 years in this country indicated that the efficacy and safety have been high.

Allergens↗
PubMed1999

[Clinical observation of curative effect of neartotal larynegectomy for advance laryngeal cancer].

OBJECTIVE: To explore a method how to preserve the speech function affer larynegectomy for advance laryngeal cancer and to improve the patients' life quality. METHOD: 17 cases with advance laryngeal cancer (T3 11 cases, T4 6 cases, glottic region 8 cases, supraglottic region 5 cases, pyriform recess 4 cases) were treated with neartotal larynegectomy (Pearson operation) in our department from February 1990 to July 1995. In the operations the remained monolateral arytenoid cartilage and an about 1.5 cm-wide mucomembranous flap, which joined to trachea, reconstructed vocal duct, lymphoglandulae near the branch of neck artery were checked routinely in those N0 cases, and the radical neck dissection was taken or not according the result of frozen section. RESULT: After the operation good speech function was obtained in 12 cases. All patients, except one, had good swallowing. Survival rate of 2, 3 and 5 year was 70.6%, 64.2% and 50% respectively. CONCLUSION: It is key that neck dissection should be performed rightly and the principle of surgery should be carried out for successful Pearson operation.

Adult↗
PubMed1999

[The effects of sex hormone on blood vessels].

OBJECTIVE: The protective mechanism of sex hormone on blood vessels was investigated to provide evidences for clinical use of hormone replacement therapy in postmenopausal women. METHODS: To observe the effects of 17 beta-estradiol (E2), progesterone(P), testosterone (T) and E2 combined with P on the relaxation of umbilical arterial rings (UAR) as well as production of nitric oxide (NO) in cultured umbilical endothelial cells(HUVEC) in vitro. RESULTS: The results showed that 10(-9)-10(-6) mol/L E2 dilation of UAR, but 10(-5) mol/L E2 showed vague effect. P or T had no relaxation effect, but releasing nitric oxide. When in combined trial P at 10(-5) mol/L inhibited the relaxation effect of E2 at 10(-7)-10(-5) mol/L but didn't inhibit E2 10(-9) mol/L. In HUVEC 10(-9)-10(-5) mol/L E2 stimulated the release of nitric oxide when cells incubated for 10 min and 30 min, but did not influence the NO release at 60 min. P and T have different effects on the release of nitric oxide at different concentrations and incubation time. P also inhibited the NO release induced by E2. CONCLUSIONS: The results indicated that P actually inhibited the relaxation response and induction of NO release by E2, especially at the high concentration. Therefore, we suggested that to use low doses of E2 combined with low dose P for hormone replacement therapy in prevention and treatment of cardiovascular diseases in postmenopausal patient.

Cells, Cultured↗
PubMed1999

[Morphological and histological studies of Herba Boschniakiae].

This paper deals with the morphological characters of the plants and drugs, and the histological characters of the stems of Herba Boschniakiae (Boschniakia rossica). This results provide authentic methods for the identification of Herba Boschniakiae.

Drug Contamination↗
PubMed1999

[Effects of abalong polysaccharide on the activity of the peritoneal macrophages and delayed-type hypersensitivity in mice bearing S180].

The effect of Abalone polysaccharide(Ap) which extracted from Haliotis discus hannai Ino on phagocytosis activity of the peritoneal macrophages and delayed-type hypersensitivity in mice bearing S180 were studied. The results showd that the ablong polysaccharide promoted the phagocytosis activity of the peritoneal macrophages and delayed-type hypersensitivity in mice bearing S180. It was suggested that the polysaccharide inhibited tumor growth maybe by activating the macrophage and T cells.

Animals↗
PubMed1999

[Karyotype analysis of Carpesium cernuum].

The paper reported the chromosome number, karyotype and chromosome volume of Carpesium cernuum. The normal diploid was 2n = 40, karyotype formula based on Levan's publication was k(2n) = 40 = 24 m + 12 sm + 2 st + 2T. According to the method of S. R. Kuo, the chromosome relative length was 2n = 40 = 8L + 6M2 + 16M1 + 10S, which belong to "2B" type according to the Stebbins' karyotype classification. The AS.K% was 62.35% from Arano's method. The total volume of chromosome groups was 13.76 microns 3.

Asteraceae↗
PubMed1999

[Synergy and attenuation of cyclophosphamidum (CTX) activities by abalone polysaccharide].

Abalone polysaccharide (AP) was extracted from Haliotis discushannai Ino. The combined effects of AP and CTX against tumor-bearing mice were investigated. The results showed that AP could markedly promote the inhibition effects of CTX on S180 and HepA tumor, enhance protection against leukocytopenia, decrease of spleen and thymus weight and hemolysin in serum, and bone marrow supression induced by CTX.

Animals↗
PubMed1999

[A multichannel infrared telemetry system for physiological signal].

This paper introduces the multichannel infrared telemetry system for temperature, respiration and ECG measurements. The experimental results are given at the end of the paper. This infrared telemetry system can be used in the environment with high electromagnetic interference, such as the operating room with electrosurgical unit and become an important monitor device.

Electronics, Medical↗
PubMed1999

[The development of a two-channel impedance pneumography].

To obtain respiratory signals with impedance method at two measuring frequencies, a high-performance two-channel impedance pneumography was implemented and the software including acquisiting data, showing waves, storing datas were developed. Human experiment was done and the results were also presented.

Breath Tests↗
PubMed1999

[Investigation and analysis of pregnancy gingivitis in 700 pregnancy women]

OBJECTIVE: To investigate the relation between the incidence of pregnancy gingivitis and pregnancy period as well as oral hygiene of pregnancy women. METHODS: From January 1995 to April 1996,700 pregnancy women were inquired and examinated clinically. RESULTS: The incidence of pregnancy gingivitis is 73.57%,of which,the incidence during the first trimester is 67.49%,the second 74.19% and the third,79.17%.The incidence of pregnancy epulis is 0.43%. CONCLUSION: The incidence of pregnancy gingivitis was increasing following the pregnancy month and sexual hormone.It was important of pregnancy women to consulting about oral hygiene.

Journal Article↗
PubMed1999

Apoptosis of hemopoietic cells in irradiated mouse bone marrow.

Apoptosis of hemopoietic cells in bone marrow following radiation has been rarely reported, let alone studied quantitatively and pathologically. LACA mice were irradiated with 2.5, 4.0, 5.5, and 7.0 Gy gamma-rays, and the bone marrow was examined at 6 hours, 1 day, and 3 days after radiation. Semi-thin and thin sections were examined by light and electron microscopy. The number and area density of the apoptotic cells were assessed by means of a Cambridge Quantimet 970 Image Analyzer. We found that apoptosis occurred in only a few hemopoietic cells in the control mouse bone marrow, whereas 6 hours after radiation there were many apoptotic hemopoietic cells in each sample of irradiated bone marrow. Compared with controls, both the number and area density of the apoptotic cells markedly increased in the bone marrow of animals in every radiation dose group, and the difference was statistically significant (p < 0.01). Furthermore, the number and area density increased as the radiation dose increased. Our findings suggest that apoptosis is the main mode of radiation-induced hemopoietic cell death.

Animals↗