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Biomedical subjects

L Zhao

Publications and source records attributed to L Zhao.

At least 109 records · Page 6Linked to original sources
PubMed2001

[Bioaccumulation mechanism of red tide alga Prorocentrum micans for heavy metal ions].

Pollution of heavy metal from industrial wastewater is a worldwide environmental problem. Biosorption is an effective technology for the treatment of low concentration industrial wastewater. The purpose of this study was to evaluate the heavy metal uptake capacities of the biomass of marine red tide Prorocentrum micans. All red tide biomass used in this study were obtained from cultivation in our lab. Batch experimental results showed that living and non-living biomass of P. micans killed by CH2O were similar setting property for Cu2+, Pb2+, Ni2+, Zn2+, Ag+ and Cd2+. This study indicated that biomass of P. micans has a high capacities for above six heavy metal and the kinetics under the conditions studied were relatively fast. About 90% of the biosorption occurred within 10 min and an equilibrium was reached in 30 min. The Biosorption capacities for heavy metal ions were strongly dependent on pH of the solution, and higher capacities were obtained at pH around 5 and higher. Bonding and FIR of P. micans polysaccharide obtained by the hot water method for Cu2+, Pb2+, Ni2+, Zn2+, Ag+ and Cd2+ was also studied. The study indicated that -OH and -CONH2 groups were active center of biosorption.

Adsorption↗
PubMed2001

[Comparison of effects of 5 and 20 Hz magnetic field on cerebral ischemia in rats].

OBJECTIVE: To compare the effects of 5 Hz and 20 Hz magnetic field on cerebral ischemia in rats. METHOD: After cerebral ischemia was produced by ligation of the left general carotid artery, rats were stimulated by magnetic fields of 5 Hz and 20 Hz respectively and pathological changes in neurocytes were observed. RESULT: (1) Different pathological changes were observed in different cells; (2) The extent of damage of pyramidal cells was milder in 5 Hz magnetic field groups than those in the control group, and the effect was not remarkable in the 20 Hz group; (3) The effect on astroglia was worse in 5 Hz group than that in control and 20 Hz group. CONCLUSION: Magnetic field stimulation influences cerebral ischemic reaction with frequency-dependency.

Animals↗
PubMed2001

[Analysis on HLA-E polymorphism in Shanghai Han population].

OBJECTIVE: To investigate the distribution of HLA-E alleles in Chinese Han in Shanghai area. METHODS: HLA-E alleles were assigned by using a PCR/SSO method in 201 random healthy individuals from Shanghai region. HLA-A,-B antigens typing was carried out with NIH standard microlymphocytoxicy method. RESULTS: Three alleles of HLA-E could be detected in this population. The E*0101 is the most common allele with a frequency of 42.29%, followed by E*01032 and E*01031 with 32.84% and 24.88% respectively. No E*0102 and E*0104 could be detected in all of the individuals. The analysis of linkage on two loci between HLA-E and HLA-A or -B showed that no significant difference could be found between expected frequencies and observed frequencies excepting B15/E*01032 and A2/E*01032. CONCLUSION: The allele frequencies of HLA-E are 42.29% for E*0101, 24.88% and 32.84% for E*01031 and E*01032 respectively in Shanghai Chinese. No extensive linkage disequilibrium was found between HLA-E and HLA-A or -B locus.

Alleles↗
PubMed2001

[Correlation of the metabolism of oxygen free radical in ovary, uterine muscle and vein blood with the pathogenesis of endometriosis or endometrioma].

OBJECTIVE: To investigate the correlation of metabolism disturbance of oxygen free radical (OFR) with endometriosis and endometrioma, to provide an evidence for the diagnosis and treatment. METHODS: (1) The lipid peroxide (LPO), selenium (Se), superoxide dismutase (SOD) and vitamin E (VE) levels were respectively in the vein blood, ovary tissue of the chocolate cyst wall and chocolate cyst fluid in 32 operated patients with endometriosis (endometriosis group). (2) The levels above were determined separately in 23 operated patients with endometrioma (endometrioma group) and 30 cases of hysteroma (control group). RESULTS: (1) The LPO levels in vein blood and ovary tissue of endometriosis group were (6.357 +/- 1.251) mumol/L and (3.735 +/- 1.546) nmol/g protein. Which significantly higher than those of control group (P < 0.01). On the other hand, the Se. SOD. VE levels in endometriosis group were significantly lower than those in control group (P < 0.01-< 0.05). (2) The LPO level in ovary chocolate cyst fluid was higher than that in vein blood itself and control group. (P < 0.01). (3) The LPO levels in vein blood and uterine muscle of endometrioma was (5.882 +/- 1.711) mumol/L and (2.937 +/- 1.577) nmol/g protein, they were higher-than these in control group (3.547 +/- 1.640) mumol/L, (1.754 +/- 0.833) nmol/g protein, (P < 0.01). While, the Se. VE. SOD level tween the SOD level in uterine muscle tissue of endometriomin vein blood is significantly higher than those in control group (P < 0.01). There is no difference bea and control group (P > 0.05). CONCLUSION: The endome triosis and endometrioma is related to the produce or metabolistic imbalance of oxygen free radical, and so to the increasing of lipid peroxide.

Endometriosis↗
PubMed2001

[Changes of brain potentials related to auditory location discrimination during simulated weightlessness].

Objective. To study changes of brain response in distinguishing auditory location during simulated weightlessness. Method. The event-related potentials (ERPs) during auditory location discrimination were compared between head down tilt (HDT) and head up tilt (HUT) conditions among 14 healthy subjects. Result. (1) Both the target (T) and non-target (NT) auditory signals induced significant ERPS; (2) The slow potential was significantly lower for both T and NT-ERPs during HDT as compared with that during HUT; (3) The reduction of mean slow potential amplitude during HDT was more significant for the target signals from right-rear position and lightest for the target signals from right-front position. This phenomenon was more remarkable at left-front area. Conclusion. These data provide further evidence that the higher brain function was affected by simulated weightlessness.

Aerospace Medicine↗
PubMed2001

[Sewage treatment by the canal reactor with biomembrane].

This paper studies that utilizing sewage canal (waterway) of city to treat sewage on bases of researching water pollution, hydrological data and topography of the canal. A new canal reactor of bacteria membrane with continuous operation was designed, made and studied in the laboratory. The operation results of the reactor show that the reactor could effectively treat the sewage of city. The average data of continuous operation during 3 months showed that the removal ratios of CODCr and BOD5 were 88% and 95% in the range of CODCr concentration 180 mg.L(-1)-450 mg.L-1 in the inlet, separately. The technology also has the advantage of low capital cost, low operation cost. This will create the condition to apply the way to practical living sewage treatment of canal.

Bacteria↗
PubMed2001

[A study on the epidemiological characteristics and the preventive measures of rabies in Shanghai].

OBJECTIVE: To analyze the epidemiological characteristics and the preventive measures of rabies in Shanghai from 1950 to 2000. METHODS: Suspected cases of rabies were investigated epidemiologically and collection of samples to isolate the virus. RESULTS: The most highest morbidity of rabies was 1.98/100,000 in 1950. There had been neither case of rabies, nor the rabies virus positive identified in dogs between 1958 and 1988. The morbidity of rabies was 0 - 0.03/100,000 from 1989 to 2000. According to the data of 20 reported cases from 1985 to Sept. 2000, the mean incubation was 66.37 days, except one case of 14 years. The mean course of diseases was 4.55 days. Seventy percent of the cases did not receive any preventive measure. A hundred and ninety-four persons who were bitten by rabies virus positive dogs were timely treated and all of them survived. In recent years, there has been more than 50,000 persons bitten by dogs every year in Shanghai. The rate of rabies vaccine immunization was over 95%. The rate of anti-rabies serum immunization was over 20%. CONCLUSION: Rabies is a preventable disease even when persons were bitten by dogs with rabies virus positive. The important measure is to treat the wound timely, giving vaccine and anti-rabies serum injection. According to the regulation of dog control in Shanghai, the number of dogs be kept at the lowest level, immunizing all the registration dogs, and destroying the none-registration dogs are the most essential measures to be taken.

Animals↗
PubMed2001

[Changes of early components of auditory ERPs during HDT-simulated weightlessness].

Objective. To study changes of early components of the auditory ERPs during simulated weightlessness. Method. The event-related potentials (ERPs) during an auditory location discrimination were compared between head down tilt (HDT) and head up tilt (HUT) conditions in 14 normal subjects. Result. The early components of T-ERPs and NT-ERPs decreased significantly during HDT as compared with that during HUT. The reduction of mean potential amplitude during HDT was more marked at left-forehead area (F5). Conclusion. These data provided further evidence showing that the early activity process of brain was also affected by simulated weightlessness.

Adult↗
PubMed2001

[The prognostic value of serum neuron specific enolase detection in small cell lung cancer].

OBJECTIVE: To evaluate the prognostic value of NSE detection in small cell lung cancer. METHODS: 144 unresectable small cell lung cancer patients were eligible in the retrospective study. NSE was analyzed before chemotherapy and 21 days after chemotherapy using ELISA method. RESULTS: For D1-NSE, 98 (68.1%) were NSE positive and 46(31.9%) were NSE negative; for D21-NSE, 57(39.6%) were NSE positive and 87 (60.4%) were NSE negative. In univariate analysis, both D1-NSE and D21-NSE have prognostic significance. But in multivariate analysis only D21-NSE is an independent prognostic factor. CONCLUSION: D21-NSE in small cell lung cancer is an independent prognostic factor and may be proposed for use in the clinic and research.

Adult↗
PubMed2001

[Influence of oral administration of realgar on contents of copper, zinc and selenium in rat tissues].

OBJECTIVE: To investigate the changes of copper, zinc and selenium levels in rat tissues after long-term oral administration of Realgar. METHODS: Rats were given Realgar with dosage of 50, 150, 450 mg.kg-1.d-1 for 5 weeks, and the concentrations of copper, zinc and selenium in different rat tissues as well as the contents of metallothionein in rat liver and kidney were determined with atomic absorption and hydride generation-atomic fluorescent technique. The total amount of copper excreted from feces and urine of each rat 5 days before the rat was killed was also measured. RESULTS: No significant changes of levels of copper, zinc and selenium in rat tissues were found after administration of low and middle dosages of Realgar. But higher dosage (450 mg.kg-1.d-1) of Realgar administration could induce a small but significant decrease of zinc concentration in hearts and a increase of copper contents in spleen and tibia, as well as twice more copper concentration of kidney. CONCLUSION: Copper deposit in kidney was the most significant change found among the trace elements levels in rat tissues, and this might be one of the mechanisms for kidney toxicity of Realgar.

Administration, Oral↗
PubMed2001

[Screening of anti-bacteria activity of extracts of Gaultheria leucocarpa var. yunnanensis].

OBJECTIVE: To further develop Gaultheria leucocarpa var. yunnanensis, anti-bacteria constituents in it were screened. METHOD: The constituents were extracted by chromatographic process. The anti-bacteria test was made with regulatory method of analysis. RESULT AND CONCLUSION: Anti-bacteria test with extracts of water, acetic ester and n-butanol showed that 3 extracts from 22 samples had anti-Staphylococcus aureus action, and the extracts from root and stem showed the same result. 2 extracts could kill Escherichia coli and Pseudomonas aeruginosa. The lower the concentrate, the less the anti-bacteria action was. These results suggested that not only essential oil but other ingredients from G. leucocarpa var.yunnanensis have anti-bacteria activity. Anti-fungi test of the same extracts didn't indicate remarkable action.

Anti-Bacterial Agents↗
PubMed2001

[A survey on the effects of "Dietary Guideline" nutrition education project].

A survey on the nutrition knowledge, attitude and behavior of 5145 persons from five cities of four provinces, Shandong, Guangdong, Sichuan and Heilongjiang, before and after the nutritional education project on "Dietary Guideline" has been effectively conducted. An obviously good effect has been achieved among the residents, middle and primary school students and elderly people. Before the nutritional educational project has been carried out, the people who understanding the "Dietary Guideline" was only 12.0%, 29.2% and 15.2% of residents, the elderly and students respectively. But after education, the rates raised to 93.4%, 99.0% and 91.9% respectively. Nearly 90% of residents and the elderly got to know the "Dietary Guideline" through the materials distributed from the project. The nutrition knowledge score was improved greatly after the project was conducted. The attitude towards learning nutrition knowledge was good. At the same time, some dietary behavior and the life style of people had been modified. These results indicated that nutrition education is very important on improving people's nutrition knowledge level, changing people's unhealthy living attitudes and dietary habits.

Adolescent↗
PubMed2001

[Use transposon and parDE through in vivo cloning to promote the genetic stability of plasmid pCPP430].

Plasmid pCPP430 carrying the hrp gene cluster after transformated into 308R (Pantoea agglomerans) can cause the hypersensitive response, and simultaneously induce the plant resistance to disease. It was genetically unstable in P. agglomerans. 0.8 kb parDE region of the broad-host range plasmid RK2 is responsible for plasmid partition. It can mediate plasmid maitenance of many kinds in Rhizobium meliloti, and also can promote the genetic stability of recombinant plasmid in the biocontrol bacteria P. agglomerans. In this paper, we cloned parDE into pCPP430 in vivo through transposition to promote its genetic stability. parDE was amplified by PCR, inserted into pGEM-T vector and cut out and religated to NotI-cut transposon vector pUT/mini-Tn5 Km to get a parDE containing mini-Tn5, pTnp. After conjugation between S17-1/lambda pir (pTnp) and 308R (pCPP430), parDE was cloned in vivo into plasmid pCPP430 to obtain pRTnp. It was demonstrated that the insertion of parDE in pCPP430 increased significantly the plasmid's stability in P. agglomerans.

Bacterial Outer Membrane Proteins↗
PubMed2001

[Experimental study on protective effective of congsheng capsule in acute cerebral ischemia and improvement of cerebral blood flow and energy metabolism].

OBJECTIVE: To investigate the protective effect of Congsheng capsule (CSC) on acute cerebral ischemia in mice and rats. METHODS: Cerebral ischemia model was established by adding FeCl3 to block the blood flow of unilateral middle cerebral artery (MCA) for 30 mins. Acute incomplete cerebral ischemia was induced by ligation of bilateral carotid arteries in rats. Bilateral carotid arteries of old mice were repeatedly ischemia and reperfusion combined with caudal bloodletting to build the cerebral ischemia model. The effect of CSC on neurologic symptom, cerebral infarction size, cerebral water content, cerebral blood flow and cerebral tissue energy metabolism were observed. RESULTS: CSC 1, 3, 6 g/kg obviously reduce the size of cerebral infarction and cerebral water content, markedly improve the neurological symptoms and cerebral blood flow; 3, 6 g/kg significantly ameliorate the energy burden. CONCLUSION: CSC has anti-cerebral ischemia function through increasing blood supply of cerebral tissue and improve the energy metabolism.

Animals↗
PubMed2001

[Construction of recombinant plasmids containing genes of HBsAg and their expression in the eukaryotic cells].

OBJECTIVE: To construct recombinant plasmids expressing L, M, S and pre-S1-S protein of HBsAg. METHODS: Amplifying segments of S, pre-S2-S, pre-S1-pre-S2-S genes of HBV by PCR and amplifying segment of pre-S1-S by overlap extension PCR; inserting the segments into Rc/CMV and pSG5UTPL/Flag plasmids respectively and exploring their expressions by Western-Blot hybridization, identifying the inserting segments by sequencing. RESULTS: The sequences of the inserted segments were the same as the genes of S, pre-S2-S, pre-S1-pre-S2-S and pre-S1-S and the results of Western-Blot hybridization were positive for the aimed proteins. CONCLUSION: We have gained 8 recombinant plasmids expressing S, M, L and pre-S1-S proteins with high efficacy.

Base Sequence↗
PubMed2001

[Detection of hepatitis C virus from hepatocellular carcinoma and its relationship to hepatocarcinogenesis].

OBJECTIVE: To get an insight of the relationship between hepatitis C Virus (HCV) infection and hepatocellular carcinoma (HCC). METHODS: A molecular pathology research was performed. Liver specimens from 19 HCC cases with HCV infection only were detected for HCV antigen (HCAg) and HCV RNA with monoclonal antibody (McAb) against HCV NS3 antigen by means of immuno-histochemistry staining and in situ hybridization using Dig-labeled full-length HCV cDNA Probe. RESULTS: In 17 of 19 (89.5%) cases, positive expression of the antigen was observed; 11 of 19 (57.9%) cases were positive for HCV RNA. The viral antigen was expressed in cytoplasm and nucleus of para-cancerous hepatocytes and in cancer cells too, while the distribution of HCV RNA was only seen in cytoplasm of hepatocyte. CONCLUSION: These results strongly support the relationship between HCV infection and the occurrence of HCC. The nucleic distribution of HCAg suggests a possible interaction between HCAg and the host genome, which may lead to hepatocarcinogenosis.

Aged↗
PubMed2001

[Determination of Pd, Pt and Au by microwave plasma torch atomic emission spectrometry using an on-line clean-up].

In this paper, in the presence of Li+, Na+, K+, Ca2+ and Mg2+, determinations of Pd, Pt and Au by microwave plasma torch atomic emission spectrometry (MPT-AES) using an on-line clean-up were studied. It was shown from the experiments that these interfering matrix elements might be removed with the strong acidic cation exchange resin. The method was applied to the analysis of some practical samples and the results obtained were satisfactory.

Cation Exchange Resins↗