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Biomedical subjects

Wei Liu

Publications and source records attributed to Wei Liu.

At least 469 records · Page 26Linked to original sources
PubMed2002

[Construction and expression of APP(SWE) transgenic mice model].

OBJECTIVE: To prepare transgenic mice model of human Swedish mutation of amyloid precursor protein(APP(SWE)) gene. METHODS: By pronuclear microinjection, human APP (SWE) genes were microinjected into pronuclei of zygotes of C57 and Kunming white mice. Integral zygotes were implanted into the oviducts of pseudopregnant female mice. The integration and expression of exogeneous genes in offsprings were detected by polymerase chain reaction (PCR), fluorescence in situ hybridization (FISH) and reverse transcription-ploymerase chain reaction (RT-PCR) analysis. RESULTS: The success rate of microinjection and the birth rate were 76.62% and 10.38%, respectively. There were 6 founders and the integration rate was 35.29%. The exogeneous gene was transferred to the third generation. Expression of human APP(SWE) gene was detected in the brain, heart and muscle but not detected in the liver and kidney of transgenic mice. CONCLUSION: The transgenic mice model of human APP(SWE) gene has been prepared successfully.

Amyloid beta-Protein Precursor↗
PubMed2002

[Superselective arterial embolization for hemorrhage from malignant gestational trophoblastic tumor].

OBJECTIVE: To evaluate the efficacy of superselective arterial embolization to control hemorrhage from malignant gestational trophoblastic tumor. METHODS: From February 1990 to June 2001, 31 patients (choriocarcinoma 24, invasive mole 7) with hemorrhage from malignant gestational trophoblastic tumor were treated with superselective arterial embolization. The hemorrhage organs included uterus (22 cases), vagina (3 cases), liver (3 cases), bladder (2 cases), and intestine (1 case). RESULTS: In 28 cases (90.3%), superselective arterial embolization successfully controlled the hemorrhage. Hysterectomy was performed in the 3 failed and uterine perforation was revealed by laprotomy. Four patients had normal term delivery after successful superselective arterial embolization and chemotherapy. CONCLUSION: Superselective arterial embolization can effectively control the hemorrhage from malignant gestational trophoblastic tumor.

Antineoplastic Agents↗
PubMed2002

[CT pulmonary functional imaging in emphysema: a correlative study of CT technique and pulmonary function test].

OBJECTIVE: To compare the effectiveness of high resolution CT, CT pulmonary functional imaging, and pulmonary function test (PFT) in the quantitative evaluation of emphysema and obstructive pulmonary disease. METHODS: The study included 37 patients with obstructive ventilatory defect and 20 normal controls. CT and pulmonary function test were performed in all subjects in one week. Correlation between and differences among HRCT visual scoring, parameters of CT pulmonary functional imaging and the result of pulmonary function test were compared. RESULTS: (1) Emphysema was detected by CT in 23 of the 37 patients with obstructive ventilatory defect. (2) HRCT visual scoring was correlated only with D(L)CO% (r = -0.731, P < 0.001) among other pulmonary function parameters. (3) HRCT visual scoring in patients with enrphysema was correlated with pixel indices (PI) at full inspiration and expiration. Visual scoring showed the best correlation with PI(-910in) (r = 0.506, P < 0.001) and PI(-910ex) (r = 0.610, P < 0.001). (4) The grading of pulmonary function based on PI(-910in) and PI(-910ex) showed no difference from the grading by pulmonary function tests (chi(2) = 0.527, P = 0.913; chi(2) = 3.645, P = 0.302). The grading of emphysema based on PI(-910in) accorded with the grading by pulmonary function tests (chi(2) = 2.59, P = 0.459). CONCLUSIONS: HRCT is more sensitive than conventional CT in diagnosing emphysema. However, in terms of slice thickness and radiation dose, it cannot be used in the evaluation of both lungs. CT functional imaging is easily performed, and the results are objective and correlated with the result of HRCT visual scoring and PFTs. It may be, therefore, more useful in diagnosing early emphysema and evaluating lung function.

Adult↗
PubMed2002

[Repair of porcine full-thickness skin defects with autologous tissue engineered skin].

OBJECTIVE: To explore a feasible method to repair full-thickness skin defects with tissue engineered techniques. METHODS: The skin specimens were cut from the Changfeng hybrid swines' abdomen, then keratinocytes and fibroblasts were isolated and harvested by trypsin, EDTA and type II collagenase. The cells were seeded in petri dishes for primary culture. When the cells were in logarithmic growth phase, they were treated with dispase II (keratinocytes) or trypsin (fibroblasts) to separate them from the floor of the tissue culture dishes. A biodegradable material-pluronic F-127 was prefabricated and mixed with these cells, and then the cells-pluronic compounds were seeded evenly into polyglycolic acid (PGA). Tinally the constructs were replanted to autologous animals to repair full-thickness skin defects. Histological changes were observed in 1, 2, 4 and 8 weeks postsurgery. RESULTS: The cells-pluronic F-127-PGA compounds could repair autologous full-thickness skin defects. Histologically, the tissue engineered skin was similar to normal skin with stratified epidermis overlying a moderately thick collageneous dermis. CONCLUSION: Tissue engineered skin can repair autologous full-thickness skin defects with primary-cultured keratinocytes and fibroblasts as seed cells and PGA as a cell carrier.

Animals↗
PubMed2002

[Tumor of the skull-report on 119 patients].

OBJECTIVE: To study the pathologic type, clinical manifestations and treatment of skull neoplasms. METHODS: A series of 119 patients with skull neoplasm were analyzed retrospectively with respect of clinical manifestations, radiologic features, treatment and prognosis. RESULTS: 122 operations were done with 3 patients being operated twice. Complete resection was done 75 times, subtotal resection 24 times, partial resection 22 times and biopsy only once. Gross type: exophytic 43(36.1%), endophytic 27(22.7%) and mixed type 49 (41.2%). Among the 85 patients followed, 78.6% have recovered and are living well, 16.6% of patients are self-caring, 2 need others' help and 2 have died. CONCLUSION: Most skull neoplasms require neurosurgical intervention. Surgical excision is able to confirm the diagnosis, slow down the progression of neurologic dysfunction, prolong the patients' lives and improve the cosmetic results.

Adolescent↗
PubMed2002

[Qualitative study of drug-using and sexual behaviors of drug users in Guangxi].

OBJECTIVE: To understand where and how drug-using and sexual behaviors occurred among drug users. METHODS: Twenty-five drug users were recruited from detoxification centers and communities. In-depth interview was used to collect information about drug-using and sexual behaviors. Each subject was interviewed separately and privately for about 2 - 3 hours. RESULTS: Most drug users shifted from oral taking drugs to injecting drugs in order to reduce economic burden and look for "high feeling". Reasons for not injecting among few drug users included 'perceiving information on harm of injection', 'over-dose death' or 'infection with HIV'. Most drug users knew that HIV transmit through sharing needles or having sexual intercourse without using a condom. However, needles were shared at night when drug or needles were scarce. Promiscuous sexual relationship was common among drug users. Most female drug users had engaged in prostitution but few used condoms. CONCLUSION: High-risk drug injecting behaviors and high-risk sexual behaviors were prevalent among drug users despite knowledge on HIV transmission and prevention. Thus, education alone would not work unless specific intervention programs are taken.

Adolescent↗
PubMed2002

Clinical pathological study of treatment of chronic hepatitis with hyperbaric oxygenation.

OBJECTIVE: To detect the feasibility and theoretic basis for treatment with hyperbaric oxygenation (HBO) in chronic hepatitis and to compare the changes in hepatic function, immunity, pathologic morphology, ultrastructure and HBV in hepatic tissues before and after treatment. METHODS: Sixty cases of chronic hepatitis were randomly selected and divided into two groups: the experiment (n = 30) and control groups (n = 30). Patients in the experimental group were treated with HBO for 6 courses. Patients in the control group were treated for 60 days with the usual drugs used in the clinic. The function and bloodstream graph of liver were examined and liver biopsies were made before and after treatments. Routine paraffin sections were stained with HE and observed under the light microscope. Ultra thin slides from paraformaldehyde and glutaraldehyde fixed liver tissue were stained with lead citrate and observed with the transmission electric microscope. HBsAg and HBcAg in liver of the experimental group were detected with ABC immunohistochemistry method before and after treatment. RESULTS: For the experimental group, ALT, SB, gamma-GT, AKP, IgG, and IgM in blood and the degeneration and necrosis of hepatocytes were remarkably decreased (P < 0.05 ), the mean contractive wave of bloodstream in liver and the bloodstream in right ramus of janitrix were remarkably increased (P < 0.05), and the swelling of mitochondria, increase of lysosomes, generation of Kupffer cells, infiltration of lymphocytes in portal area and capillary generation were all remarkably all eviated (P < 0.05) after treatment with HBO. There were significant differences between the experimental and control groups after treatment with different methods (P < 0.05). For patients in the experimental group, the fibrosis and fat-storing cells in the liver were not reduced (P > 0.05), and the expression of HBsAg and HBcAg in liver was not weakened (P < 0.05) after treatment. CONCLUSIONS: Treatment with HBO for chronic hepatitis was effective and recommendable, but it could not reverse liver fibrosis. However, it might be able to delay or prevent the liver from fibrosis, so it might be more effective at the early and middle stages of chronic hepatitis. HBO could not inhibit the HB virus. So we consider that treatment with HBO should be simultaneous with anti HBV therapy.

Adult↗
PubMed2002

Percutaneous microwave coagulation therapy for lung cancer.

OBJECTIVE: To evaluate the clinical effect, CT image changes and side-effects of percutaneous microwave coagulation therapy for lung cancer. METHODS: CT-guided percutaneous puncture was performed using a needle mono-pole microwave antenna with 65W, 2 450 MHz microwave delivered in 60 seconds to 20 peripheral lung cancer patients, including 8 suffering from primary lung cancer and 12 metastatic lung cancer (totally 28 lesions). RESULTS: Sixteen patients were alive after having been followed-up for 3 approximately 24 months. All patients showed nodules decreased in size. Diminution of over 50% was observed in 13 nodules and 3, completely disappeared. The overall response rate was 57.1%. Ellipsoid shadow 3.5 cm x 2.5 cm across was observed by CT in lesions immediately after coagulation. Gasification within the coagulated area was observed in a week with a high density in the peripheral region. Consolidation was observed in 3 months and the lesion disappeared 1 year later. Complete tumor necrosis was proved by biopsy. No side-effects or complications were observed. CONCLUSION: Percutaneous microwave coagulation therapy is a new safe treatment for lung cancer, giving marked effect but minimum trauma.

Follow-Up Studies↗
PubMed2002

[Study on the life expectancy of residents in Xinjiang Production and Construction Group, from 1997 to 1999].

OBJECTIVE: To understand the life expectancy of residents in Xinjiang production and Construction Group, from 1997 to 1999. METHODS: Stratified cluster sampling method was used to obtain mortality rate, sequence of death causes, life expectancy, life eliminated major cause of deaths, years of potential life lost (YPLL) and level of long life. These indeices were used to compare and analyze health status on residents in the area. RESULTS: The life expectancy on residents in the area was 75.61 years old for all residents, 72.73 years old for males, 80.02 years old for females from 1997 to 1999. The life expectancy for people living in agricultural and livestock farms was lower (73.97 years old). It was found that life expectancy was parallel to the level of economy. Life expectancy of northern residents was higher than those living in the southern and eastern parts of the area. The annual average mortality rate of the residents was 5.17 per thousand (standard mortality rate 4.02 per thousand ). The sequence of major causes of death was shown as below: malignant tumors, cerebrovascular diseases, respiratory system diseases, cardiac diseases, accidental deaths, infectious diseases, certain conditions originated in the perinatal period. In the life eliminated major cause of deaths, respiratory system diseases and certain conditions originated in the perinatal period were higher than others. In both sequences of YPLL and SYPLL for major causes of death, accidental death was always in the leading place. There was a higher longevity on residents from the better economic area. CONCLUSIONS: Higher life expectancy in the area was noticed, but the differences among the different area were bigger. In order to improve the level of health on all residents in the area, it is necessary to strengthen the administration on social and natural environment of the area. Furthermore, decreasing accidental deaths, controlling respiratory system diseases (especially for infant) and improving health care of infants in perinatal period are very important tasks in the area.

Adolescent↗
PubMed2002

Characteristics of eye movement and cognition during simulated landing of aircraft.

Objective. To examine how the subject scans different parts of display panels and how the attention is distributed through the analysis of the eye movement principle and the cognition of the brain. Method. An experiment was conducted to simulate the airplane's landing course and eye movement data were recorded with eye movement measure system (EMMS). Result. There were three regions of interest (ROI) on which the subject's attention was concentrated. The subject's visual activity was active in the three ROIS and attention's shifting and distribution was between ROIS. Conclusion. Eye movement were driven by the top-down processing and the distribution of the attention. The consequence of the eye movement makes the subject maintain a continuous situation awareness.

Aircraft↗
PubMed2002

[Overexpression of truncated type II transforming growth factor-beta receptor in dermal fibroblasts].

OBJECTIVE: To study the effect of overexpression of truncated type II TGF-beta receptor on transforming growth factor-beta 1(TGF-beta 1) autoproduction in normal dermal fibroblasts. METHODS: In vitro cultured dermal fibroblasts were treated with recombinant human TGF-beta 1(rhTGF-beta 1) (5 ng/ml) or recombinant adenovirus containing truncated type II TGF-beta receptor gene (50 pfu/cell). Their effects on regulating gene expression of TGF-beta 1 were observed with Northern blotting. RESULTS: rhTGF-beta 1 up-regulated the gene expression of TGF-beta 1 and type I procollagen. Overexpression of truncated receptor II down-regulated the gene expression of TGF-beta 1. CONCLUSION: Overexpression of the truncated TGF-beta receptor II decreases TGF-beta 1 autoproduction via blocking TGF-beta receptor signal. The results may provided a new strategy for scar gene therapy.

Cell Division↗
PubMed2002

[Significance of serological test of blood group in nonmyeloablative allogeneic peripheral blood stem cell transplantation of patients with acute leukemia].

The purpose of this study is to explore the clinical significance of RBC blood group serological test in nonmyeloablative allogeneic peripheral blood stem cell transplantation (NAPBSCT) of ABO group incompatibility in 4 patients with acute leukemia. ABO and MN blood group of donors and recipients were determined by hemagglutination test and Rh blood group by Diana Gel phenotype Rh card. The changes of blood group in recipients were observed and implant of donor cells was monitored by short tandem repeat-PCR method. The results showed that in 2 cases of 4 recipients the marrow cells appeared mixed chimera of donor and recipient cells, and blood group changed to donor type in 1 of the 2 cases on 100 days after transplantation. In another 2 cases, the marrow cells appeared mixed chimera without blood group chimera on 154 days after transplantation, and rejection of the transplant occurred in 1 of the 2 cases. The determination of hemagglutinin titer showed that the implant rate of donor cells was lower in the recipients with higher hemagglutinin titer and blood group chimera did not appear, conversely, the implant rate was higher in the recipients with lower titer and blood group chimera appeared early. It is concluded that examination of RBC blood group in NAPB SCT can indirectly reflect effectiveness of transplantation, contribute to decide the intensity of conditioning protocol and immunosuppressive therapy after transplantation, estimate prognosis and guide blood transfusion during transplantation.

Adult↗
PubMed2002

[Effects of chlorine on the antigenicity and RNA polymorphism of hepatitis A virus].

The mechanisms of HAV inactivated by chlorine was investigated by enzyme-linked immunosorbent assay and RNA fingerprinting. Arbitrary primed PCR were involved to detect the changes of antigenicity and RNA polymorphism respectively before and after inactivation by chlorine. The results showed that the infectivity was completely inactivated at 10 mg/L or 20 mg/L of chlorine for 30 minutes and the contacting time should be prolonged to 60 minutes when the loss of antigenicity was observed at the same condition. The changes of RNA polymorphism were often observed while the infectivity was completely inactivated except the concentration of chlorine was 10 mg/L for 30 minutes. The results implied that HAV inactivation by chlorine might be the result of destruction of some fractions of HAV genome but not the whole HAV genome.

Antigens, Viral↗
PubMed2002

Analysis of human two-dimension target-aiming movement.

Objective. To study the problem of human movement characteristics of target-aiming movement. Method. The authors first analyzed the essentials of target-aiming movement on the basis of previous research results, then designed and made a two-dimension experiment of target-aiming movement. Result. After theoretical consideration and analysis of experimental results, a new model of human two-dimension target-aiming movement was proposed, and the coefficients are determined experimentally. Conclusion. The model was verified by experimental data. It was demonstrated that the new model has an excellent suitability, and is applicable for evaluations of target-aiming movements of one and two dimensions.

Adult↗