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Biomedical subjects

P Li

Publications and source records attributed to P Li.

At least 127 records · Page 7Linked to original sources
PubMed2001

[Genetic analysis of dominant earliness of rice genic male sterile line 6442S-7].

F1 progenies of a genic male sterile and early maturing indica line 6442S-7 crossed with sixteen medium or late maturing varieties, such as Minghui 63, shared the same heading date as 6442S-7 under long day and short day, suggesting that 6442S-7 has completely dominant earliness. Segregation of heading dates of the F2 and B1F1 populations indicated that the earliness of 6442S-7 is mainly controlled by two dominant major genes. Whereas, heading dates of F1 progenies of 6442S-7 crossed with other four late maturing varieties, i.e. IR68, Xianguo, 9311, and BG1639, closed to the mid-parent value under long day. In F2 populations of 6442S-7 crossed with each of the four late maturing varieties, F1 from three-way crosses between 6442S-7 and each F1 of Minghui 63 crossed with each of the four late maturing varieties, and F1 from three-way crosses between 6442S-7 and each F1 of crosses between each two of the four late maturing varieties, segregation of heading dates showed that an incompletely diminant allelic suppressor for the dominant earliness of 6442S-7 existed in the late maturing varieties, IR68, Xianguo, 9311, and BG1639. It is considered that dominant earliness genes harbored in 6442S-7 have splendid future in rice improvement.

Crosses, Genetic↗
PubMed2001

Dual time point 18F-FDG PET imaging for differentiating malignant from inflammatory processes.

UNLABELLED: The aim of this study was to investigate the difference in the rates of FDG uptake between malignant and inflammatory cells and processes. METHODS IN VITRO STUDIES: (18)F-FDG uptake by different tumor cell lines (human mesothelioma [REN]; rat mesothelioma [II45]; mice melanoma [B18F10]; mice mesothelioma [AB12]; human myeloma [GM1500]; and human ovarian cancer [SKOV3]) and peripheral blood mononuclear cells isolated from 8 healthy human volunteers was measured 20 and 60 min after FDG was added into growth medium. Animal studies: II45 cells were implanted into the left flank of rats (n = 5) and a focal inflammatory reaction (mechanical irritation) was generated in the right flank. PET images at 45 and 90 min after injection of FDG were obtained and standardized uptake values (SUVs) were determined. Patient studies: Seventy-six patients who had dual time FDG PET scans were retrospectively analyzed. All results were expressed as the percentage change in SUV of the later time image from that of the earlier time (mean +/- SD). RESULTS IN VITRO STUDIES: Except for the SKOV3 cell line, which had only minimally increased FDG uptake (+10% +/- 26%; P > 0.3), all other tumor cell lines tested showed significantly increased FDG uptake over time (GM1500, +59% +/- 19%; B18F10, +81% +/- 15%; AB12, 93% +/- 21%; II45, +161% +/- 21%; REN, +198% +/- 48%; P < 0.01 for all). By contrast, FDG uptake in mononuclear cells was decreased in 7 of 8 donors. Animal studies: SUVs of tumors from 90-min images were significantly higher than those from 45-min images (+18% +/- 8%; P < 0.01), whereas the SUVs of inflammatory lesions decreased over time (-17% +/- 13% of the early images; P < 0.05). CLINICAL STUDIES: The SUVs of delayed images from the known malignant lesions compared with those of earlier scans increased over time (+19.18% +/- 9.58%; n = 31; P < 0.001; 95% confidence interval, 15.8%-22.6%). By contrast, the SUVs of benign lung nodules decreased slightly over time (-6.3% +/- 8.1%; n = 12; P < 0.05; 95% confidence interval, -10.9% to -1.7%). The SUV of inflammatory lesions caused by radiation therapy (+1.16% +/- 7.23%; n = 8; P > 0.05; 95% confidence interval, -3.9%-6.2%) and the lesions of painful lower limb prostheses (+4.03% +/- 11.32%; n = 25; P > 0.05; 95% confidence interval, -0.4%-8.5%) remained stable over time. CONCLUSION: These preliminary data show that dual time imaging appears to be useful in distinguishing malignant from benign lesions. Further research is necessary to confirm these results.

Aged↗
PubMed2001

[Super heavy oil produced water treatment by surface flow constructed wetland].

This paper adopts a new economic technology of treating super heavy oil produced water using surface flow reed wetland system. The field test was conducted at the average filtration rate of 3.33 cm/d. The average influent concentrations per year of COD, Oil, BOD5, TN were 459.16 mg/L, 27.65 mg/L, 33.52 mg/L, 13.74 mg/L, and the average effluent concentrations per year of above indices were 77.21 mg/L, 1.42 mg/L, 3.90 mg/L, 1.60 mg/L, respectively. Its respective removal ratios of COD, Oil, BOD5, TN and pH were 83.18%, 94.86%, 88.37%, 88.36%, 7.87-7.77. Analyses showed that super heavy oil produced water had no obvious effect on soil and almost no effect on growth volume and quality of reeds. Results indicated that the surface flow reed wetland could provide an efficient economical, stable new means of treating super heavy oil produced water.

Fuel Oils↗
PubMed2001

Production and localization of Muc4/sialomucin complex and its receptor tyrosine kinase ErbB2 in the rat lacrimal gland.

PURPOSE: To show the presence and forms of sialomucin complex (rat Muc4) and receptor tyrosine kinase ErbBs in the rat lacrimal gland and analyze for complexes of ErbB2 and its ligand Muc4. METHODS: Northern blot analyses were used to identify sialomucin complex/Muc4 (SMC/Muc4) mRNA in rat lacrimal gland. Immunoblot analyses were performed to detect SMC/Muc4 and ErbBs. Sequential immunoprecipitation and immunoblot analyses were used to differentiate membrane and soluble forms of the SMC/Muc4 transmembrane subunit ASGP-2. Methacarn-fixed, paraffin-embedded sections of lacrimal glands from female adult rats were immunocytochemically stained using antisera to SMC/Muc4 and ErbBs to determine their relative locations in the gland. Colocalization of SMC/Muc4 and ErbB2 was confirmed by confocal immunofluorescence. Sequential immunoprecipitation and immunoblot were performed to analyze complexes of the SMC/Muc4 and ErbB2 in the lacrimal tissue. RESULTS: Northern blot analyses of rat lacrimal glands, with a probe for SMC/Muc4, demonstrated the presence of a approximately 9-kb transcript, consistent with observations in other tissues. Similarly, immunoblot analyses with antibodies against both the transmembrane (ASGP-2) and mucin (ASGP-1) subunits showed the presence of the two SMC/Muc4 subunits in lysates from rat lacrimal gland. Significantly, two different forms of ASGP-2 were observed, a high-molecular-weight ( approximately 200-kDa) form and the more common 120- to 140-kDa form. Sequential immunoprecipitation and immunoblot analyses to differentiate membrane and soluble forms of SMC/Muc4 indicated that the high-molecular-weight form of ASGP-2 was predominantly associated with membranes, whereas the 120- to 140-kDa form was both membrane-associated and soluble. The lacrimal gland consists of acini connected by intercalated and interlobular ducts. Both acini and some intercalated ducts were stained by anti-ASGP-2 monoclonal antisera. Two patterns of acinar staining were observed: membrane staining at the borders of the epithelial cells and a granular staining within the cells. Staining of ductal surfaces with antibody to the cytoplasmic domain of ASGP-2 suggests that membrane SMC/Muc4 is being produced by the ductal cells and is not simply an adsorbed soluble product from the acinar cells. Immunoblot and immunocytochemical analyses demonstrated the presence of all four ErbBs, with ErbB2 showing the most widespread distribution, similar to that of SMC/Muc4. Immunofluorescence colocalization of membrane SMC/Muc4 and ErbB2 and coimmunoprecipitation of a complex of the two provided evidence of their association in membranes of lacrimal gland acinar cells. CONCLUSIONS: SMC/Muc4 is produced by the rat lacrimal gland as both membrane and soluble forms, specifically associated with both acinar and ductal cells. Because sialomucin complex is also present in the ocular tear film, the rat lacrimal gland represents a second source of this mucin for the tear film, in addition to the corneal and conjunctival epithelia. Moreover, the presence of a complex of SMC/Muc4 and the receptor tyrosine kinase ErbB2 in lacrimal tissue suggests that SMC/Muc4 acts as a ligand for the receptor and has functions in the lacrimal gland other than that of a mucin.

Animals↗
PubMed2001

[Genescan analysis of the loss of heterozygosity on the long arm of chromosome 6 in non-small cell lung cancer].

To investigate if there are microsatellite loci in the long arm of chromosome 6 that have close relationship with non-small cell lung cancer, Multiple PCR approach was used to analyze the 36 loci in the long arm of chromosome 6. The PCR products were analyzed in PAGE and then the electrophoresis maps were analyzed with Genescan and Genotyper. There is different LOH frequency in different loci. The total frequency of LOH in 41 lung cancers was 78%(32/41), with the highest frequency of LOH was detected on the locus D6S302(75%). There are 14 loci which have LOH frequency more than 20% and the loci are mainly located in 2 regions: 6q16.3-q21 [6 loci D6S458 (21.43%), D6S1694 (26.92%), D6S1717 (35.71%), D6S1565 (40%), D6S302 (75%), D6S1706 (36.36%) and 6q26-q27 (5 loci D6S1550 (38.46%), D6S264 (20%), D6S1585 (25%), D6S446 (33.33%), D6S281 (30.77%)], There may be tumor suppressor genes located in the two regions, which have a close relationship with non-small cell lung cancer.

Carcinoma, Non-Small-Cell Lung↗
PubMed2001

[An off site petroleum-contaminated soil bioremediation technology: soil compositing in windrow].

With off-site bioremediation technology, a soil contaminated by crude oil from Liaohe Oil Field was treated on a 20 x 10 m prepared bed. 8 composting windrow units were set, each measured 8 m in length, 2 m in width, and 0.35 m in height. The results showed that when the pollutant petroleum hydrocarbon(TPH) was within the range of 4.16-7.72 g.100 g-1 soil, the total degradation rate of TPH reached 45.19%-56.74% after 53 days operation, which indicated that a technological basis would be provided for the bioremediation of oil-contaminated soil.

Biodegradation, Environmental↗
PubMed2001

[Degradation of phenanthrene and pyrene in contaminated soil by immobilized Zoogloea sp. and Fusarium sp].

Immobilized with PVA, sodium alginate and activated carbon, both Zoogloea sp. and Fusarium sp. strains could degrade phenanthrene and pyrene efficiently. The optimal carrier was made of 100 rho.g-1 L PVA, 5 sodium alginate rho.g-1 L and 50 activated carbon rho.g-1 L. The degradation rates of phenanthrene and pyrene in 10 days were 87.48% and 75.34% by the immobilized bacterium, 37.04% and 20.85% higher than those by the free bacterium, and the rates in 15 days were 84.36% and 74.87% by the immobilized fungus, 5.35% and 11.23% higher than those by the free fungus.

Biodegradation, Environmental↗
PubMed2001

[Photobacterium phosphoreum assay on the toxicity of soil contaminated by heavy metals].

The toxicity of soil artificially contaminated by heavy metals was assessed with Photobacterium phosphoreum. The results showed that the duration of optimum balance was 24 hours, and that of optimum extraction was 2 hours. Two leaching methods were compared, and data showed that optimum leaching solvent was hydrocarbon chloride with a concentration of 0.1 mol.L-1 HCL. Dose-response curve indicated that the content of heavy metals was positively related with the toxicity of soil. The general detection limit given by EC50 of soil contaminated by single heavy metal were Cd 26.12 mg.kg-1, Cu 291.48 mg.kg-1, Zn 72.46 mg.kg-1 and Pb 2174.93 mg.kg-1. This study also indicated the toxicity of complex heavy metals pollution in soil was stronger than that of individual element. The research could provide a theoretic base for the remediation of soil contaminated by heavy metals.

Cadmium↗
PubMed2001

[Co-metabolic degradation of pyrene in soil].

High molecular weight Polycyclic Aromatic Hydrocarbons (PAHs) are always degraded by means of co-metabolism. This study compared the degradation process of pyrene as sole source of carbon and energy and co-metabolic degradation process of pyrene. The degradation rate of pyrene after 25 days in the first process was 57%, while the degradation rate of pyrene in the co-metabolic processes were about 80%. The half-life of pyrene in the co-metabolic process was shorter than those in the processes without co-metabolism. Salicylic acid, phthalic acid, sodium succinate could serve as co-metabolic substrate to enhance the degradation rate of pyrene, and sodium succinate has the best effect. There was co-metabolic relationship between pyrene and phenanthrene which was a kind of low molecular weight PAHs, phenanthrene accelerated the degradation of pyrene, while naphthalene didn't. The principle of the co-metabolism and the optimal material used as co-metabolic substrate were demonstrated in this paper.

Environmental Pollution↗
PubMed2001

[Bioslurry remediation of soil contaminated with polycyclic aromatic hydrocarbons].

Through the operation of the pilot-scale slurry reactor, the operational parameters of bioslurry remediation for soil contaminated with polycyclic aromatic hydrocarbons(PAHs), including temperature, ratio of water to soil, aeration flux, were determined. As the operational condition was that the ratio of water to soil was 2:1, the temperature was 20 degrees C-25 degrees C and aeration flux was 60 L/h, a good result of the remediation could be achieved. With the fungi isolated from contaminated soil as pure culture to degrade PAHs, after 34 days incubation, 90% of pyrene and 33.3% of benz[a]anthracene were degraded by Fusarium, 81.5% of pyrene and 49.2% of benz[a]anthracene were degraded by Mucor, 52% of pyrene and of 46% of benz[a]anthracene were degraded by Penicillium.

Biodegradation, Environmental↗
PubMed2001

Epidemiology and detection of human immunodeficiency virus among pregnant women in Hong Kong.

OBJECTIVES: To determine the epidemiology of human immunodeficiency virus infection among pregnant women and the neonatal outcomes in Hong Kong. DESIGN: Retrospective observational study composed of two parts: record review of pregnant women and unlinked anonymous screening of cord blood from neonates. SETTING: Two human immunodeficiency virus clinics and the Government Virus Unit. PARTICIPANTS: Female patients attending the two clinics who became pregnant and neonates who underwent routine metabolic screening by the Government Virus Unit between 1992 and 1999. MAIN OUTCOME MEASURES: The outcomes of neonates born to women who had human immunodeficiency virus infection during pregnancy. RESULTS: Forty-one human immunodeficiency virus-related pregnancies were recorded among 32 infected women. Fifteen pregnancies were terminated, of which 14 were in women who knew their infection status before conception. Twenty-six pregnancies continued to term, resulting in 26 live births. Twelve babies were born to women who knew their infection status before delivery. One baby was confirmed to be infected. Six women were given zidovudine for prophylaxis against vertical transmission and none of the babies were infected at birth. Of the remaining 14 human immunodeficiency virus-related pregnancies, the mothers' status became known only at a later date and nine (64.3%) babies were confirmed to be infected at the age of 18 months or older. The rate ratio of giving birth to an infected baby was 8.18 from mothers who did not know their status antenatally. Unlinked anonymous screening showed that the seroprevalence rate for human immunodeficiency virus in pregnant women was 0.032% (1/3125) in Hong Kong in 1999. CONCLUSIONS: Human immunodeficiency virus-related pregnancy is not rare in Hong Kong and the majority of infected mothers were not identified and treated. Detection of these pregnancies will be invaluable for the prevention of mother-to-child transmission. Universal antenatal screening of human immunodeficiency virus antibody is proposed as an effective strategy.

AIDS Serodiagnosis↗
PubMed2001

[Logistic regression analysis of wedge-shaped defects in the middle-aged and elderly].

OBJECTIVE: To investigate and identify the possible clinical risk factors associated with the formation of wedge-shaped defects. METHODS: Four hundred and ninety-three subjects were examined. The possible risk factors associated with wedge-shaped defects were identified by logistic regression analysis. RESULTS: The prevalence of wedge-shaped defects was observed 90.5% in this population. The prevalence and severity of wedge-shaped defects were found to be increasing with age. The correlation between age, sex, preferred side for tooth chewing, brushing twice a day, malocclusion, the formation and severity of wedge-shaped defects were noted. CONCLUSION: Occlusal factors and tooth brushing have found related to the formation of wedge-shaped defects.

Age Factors↗
PubMed2001

[A clinicopathological study of clear cell sarcoma of the kidney].

OBJECTIVE: To study the clinicopathological, immunohistochemical features and the histogenesis of clear cell sarcoma of the kidney (CCSK). METHODS: CCSK specimens from 45 pediatric cases, including 31 male and 14 female with an age range from 3 months to 12 years (mean of 3.2 years), were retrieved. Routine pathological, immunohistochemical and electron microscopic methods were utilized to analyze the CCSK specimens. RESULTS: 35 of the 45 cases were followed from 6 to 192 months. 15 patients presented with bone metastases, 6 had lung or liver metastases, 8 recurred and 20 died. Age and clinical stage at diagnosis correlated with the rate of survival. Histologically, the classic pattern of CCSK consisted of cells with pale cytoplasm, fine nuclear chromatin and indistinct nucleoli separated by an arborizing fibrovascular stroma. Other patterns were identified, including myxoid, spindle, palisading, epithelioid, sclerosing, cellular, cystic, and angiectatic. All tumors contained multiple patterns. Immunohistochemically, all cases were positive for vimentin, but negative for EMA, CK, desmin, actin, S-100, NSE, CD99, CD34 and LCA. Electron microscopy of 9 cases showed features of primitive cell conjunction and few organelles. CONCLUSION: CCSK is a common renal neoplasm of childhood. CCSK may arise from renal mesenchymal cells and has the propensity to metastasize to the bone with poor clinical outcome.

Child↗
PubMed2001

[Evaluation clinical long-term curative effect and analysis of its influence factors after restoration of teeth with wedge-shaped defects].

OBJECTIVE: To evaluate the long-term curative effect clinically and analysis of its influence factors after restoration of teeth with wedge-shaped defects. METHODS: Seventy five cases of 509 teeth with various degrees of dental wedge-shaped defects were randomly divided into two groups--the group restored by Dyract Cement and the group restored by 3M-Vitremer. Evaluation was made with the modified USPHS evaluation criterion after restoration for 1,2,4 years respectively. RESULTS: The successful rate dropped down from 2 year successful rate 85.5% to 4-year 27.7%. The new wedge-shaped defects were presented at the cervical margin of the original restoration in 1.8% (2 years later) and 6.6% (4 years later). There were a lot of influence factors on long-term curative effect. The failure rate in the group with occlusal interference was significantly higher than that without occlusal interference. CONCLUSIONS: The clinical successful rates are affected by the value of occlusal force on the restored teeth and the physical properties of the restorative materials. It is suggested that the process of restoration of dental wedge-shaped defect should include obviating occlusal factors as well as to improve the properties of restorative materials.

Adult↗
PubMed2001

[Determination of alkali metals, ammonium ion and alkyl amines by non-suppressed ion chromatography].

The determination of Li+, Na+, NH4+, K+, CH3NH2, CH3CH2NH2 and CH3CH2CH2NH2 by non-suppressed ion chromatography using sulfamic acid as mobile phase is described. A cation-exchange column was employed for separation with conductivity detection. The effect of the eluent concentration on retention value was studied. The retention value of ions decreased with increasing the eluent concentration. The suitable eluent concentration was 4.0 mmol/L. When 4.0 mmol/L sulfamic acid was used as mobile phase, the detection limits (mg/L) for Li+, Na+, NH4+, K+, CH3NH2, CH3CH2NH2 and CH3CH2CH2NH2 were 0.008, 0.029, 0.027, 0.099, 0.069, 0.163 and 0.417 and the linear ranges of calibration curve(mg/L) were 0.008-20, 0.029-20, 0.027-20, 0.099-30, 0.069-30, 0.163-40 and 0.417-40, respectively. The method has been applied to the determination of tap water samples. The recoveries of added standard were 94.0%-97.6%.

Amines↗
PubMed2001

[The effect of submucosal diathermy to the inferior turbinates on nasal airway resistance].

OBJECTIVE: The main purpose of the study is to observe the effect of submucosal diathermy to the inferior turbinates on nasal airway resistance (NAR). METHOD: Using active anterior rhinomanometry, NAR were measured in seventeen patients who suffered from chronic rhinitis before and post operation. The subjective impression of their nasal patency was assessed using a 10-point scale. RESULT: The NAR is(0.662 +/- 0.22) kPa.s/L before operation and (0.302 +/- 0.17) kPa.s/L three months after operation. The NAR is 0.397 +/- 0.25 ten months after operation. The differences are statistically significant (P < 0.01) between the NAR before and post operation. There are significant differences in the subjective impression of patients' nasal patency as well (P < 0.01). CONCLUSION: Submucosal diathermy to the inferior turbinates is effective in decreasing NAR and improving the subjective impression of their nasal patency.

Adolescent↗
PubMed2001

[Investigation on genotype constitution of different Plasmodium vivax isolates and its geographical distribution in China].

OBJECTIVE: To investigate the population constitution and geographical distribution of Plasmodium vivax in China using molecular technique. METHODS: Blood-spot filter paper samples with related epidemiological data were collected from vivax malaria patients living in malarious area of 10 provinces (autonomous region) in China. Semi-nested- or nested-allelic-specific PCR genotyping method was used to identify CSP genotypes, families and types of Plasmodium vivax of each isolate from these patients. RESULTS: Of 384 field isolates of Plasmodium vivax, 258 temperate zone family strains were identified, including 14 allelic variant genotypes spreading among 10 sampling provinces; allelic variants sized less than 731 bp were only seen in 5 provinces in southern China; 79 tropical zone family strains including 5 genotypes were also distributed in 5 provinces of southern China south to 25 degrees N. lat; and 14 PV Type-2 strains including 2 genotypes were found in some areas of Hainan and Yunnan Provinces. In addition, 33 isolates from genotype-mixed infections were revealed. CONCLUSION: At present, area north to 25 degrees N. lat. of the country is the sole area prevalent for Plasmodium vivax family strains of temperate zone; there is overlapping distribution of P. v. of temperate zone family and tropical zone family of this parasite in the southern China south to 25 degrees N. lat; where the most complex isolate constitution is in Yunnan and Hainan Provinces, and PV Type-2 strains have been found in some areas of the two provinces. Besides, there were 2 groups of genotype with distinct geographic distribution feature within the temperate zone family.

Animals↗