Search PubMed⌕ Search

Biomedical subjects

G Li

Publications and source records attributed to G Li.

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

cDNA representational difference analysis of differentially expressed cDNA sequences in human nasopharyngeal carcinoma.

OBJECTIVE: To search differentially expressed sequences correlated with pathogenesis of human nasopharyngeal carcinoma (NPC), including the candidates of tumor suppressor genes. METHODS: Representational difference analysis (RDA) was performed to isolate differentially expressed sequences between cDNA from normal human primary cultures of nasopharyngeal epithelial cells and cDNA from NPC cell line HNE1. The source of differentially expressed products were proved by Southern blot, Northern blot and in situ hybridization. The fragments were cloned with pGEM-T easy kit and sequenced by the chain termination reaction. RESULTS: Four differentially expressed cDNA fragments were isolated in the fourth subtractive hybridization using cDNA from normal human nasopharyngeal epithelial cells as tester amplicon and cDNA from NPC cell line HNE1 as driver amplicon by cDNA RDA. These differential cDNA fragments revealed that they really came from the tester amplicon and were not expressed or down-regulated in the NPC HNE1 cells. Some of the genes were expressed only in human nasopharyngeal epithelial cells but deleted or down-regulated in the biopsies of NPC. Of these obtained clones, some were the sequences of the human known genes including house-keeping genes, the others represented novel gene sequences. CONCLUSION: The differentially expressed products including the candidates of tumor-suppressor genes may be associated with the initiation of the NPC.

DNA, Complementary↗
PubMed1999

[Identification of cDNA fragments related to alpha particles radiation induced neoplastic transformation of rat tracheal epithelial cells].

OBJECTIVE: To isolate genes involved in neoplastic transformation induced by alpha-particles. METHODS: The differential display technique was used to identify differentially expressed mRNA species between primary and neoplastic transformed rat tracheal epithelial (RTE) cells induced by alpha particles. RESULTS: 15 differentially displayed gene fragments were cloned and sequenced. Seven novel ESTs were submitted to GenBank. Homology searching revealed that clone ZG35 was highly homologous to rat Annexin I gene which was thought to be involved in mitogenic signal transduction as a substrate of epidermal growth factor receptor/kinase. Clone ZC52 was nearly identical to a novel rattus norvegicus gene for carboxylesterase precursor, clone ZG52 was 3' similar to human SRPK2 gene suggesting it may be a novel SRPK2 related gene involved in pre-mRNA splicing. Clone ZA73 was a novel gene fragments, and clone ZC66 was highly homologous to rat nucleoside diphosphate kinase gene or metastasis suppressor gene nm23, sequence analysis suggested that nm23 might be mutated in the transformed RTE cells. Northern hybridization confirmed the above gene or gene fragments to be up-regulated in the transformed RTE cells. CONCLUSION: These results provide clues to elucidate the mechanisms of radiation oncogenesis and suggest that Annexin I, carboxylesterase precursor gene, ZG52 and nm23 may be involved in the neoplastic transformation induced by alpha-particles radiation.

Alpha Particles↗
PubMed1999

[The study on the personality factors in patients' satisfaction with their complete dentures].

OBJECTIVE: To find out the relation between personality factors of edentulous patients and the degree of their satisfaction to the complete dentures. METHODS: Under the condition of controlling quality of complete dentures, 165 subjects were investigated by using the patient denture satisfaction questionnaire and the revised Cattell's 16 personality factors questionnaire after wearing the complete dentures for one and three months. RESULTS: The personality factors of edentulous patients such as conscientiousness (G factor), shrewdness (N factor) and so on do affect their denture satisfaction in every aspect of the dentures. CONCLUSION: The oral prosthodontists not only need improving technological quality of prostheses but also need paying attention to patients' psychological characteristics.

Adult↗
PubMed1999

[Clinical observation on 51 patients of acute myocardial infarction treated with thrombolytic therapy combined with Chinese herbal medicine].

OBJECTIVE: To assess the efficacy of thrombolytic therapy combined with Chinese herbal medicine (CHM) in treating acute myocardial infarction (AMI). METHODS: One hundred and one cases of AMI were divided randomly into two groups. The treated group treated with thrombolytic therapy combined with CHM and the control group treated with thrombolytic therapy alone. The criteria of patency of coronary artery were conducted according to the referential standard of thrombolytic therapy in treating AMI introduced by Chinese Angiocardiopathy Medical Journal, 1991. RESULTS: The patency rate of coronary artery of the two groups were 68.63% and 56.00%, the four-week mortality 3.92% and 10.00%, hemorrhage occurrence 1.96% and 10.00%, congestive heart failure occurrence 5.88% and 16.00%, severe arrhythmia occurrence 11.76% and 22.00%, and the shock occurrence 3.92% and 8.00% respectively. The difference between the two groups was significant, P < 0.01, P < 0.05. CONCLUSION: The effect of the treated group was better and the complication occurrence of the treated group was lower than those of the control group.

Adult↗
PubMed1999

[Study on relationship between insulin-resistance and syndrome differentiation typing in hypertensive patients].

OBJECTIVE: To find the relationship between insulin-resistance and Syndrome Differentiation typing (SDT) in hypertensive patients. METHODS: Two hundred and nine patients of early stage hypertension with no complication of heart, brain or kidney were selected and classified into 4 types according to SDT, the Liver-Fire exuberant type (A), the Phlegm-Dampness abundant type (B), the Yin-Deficiency and Yang-Excess type (C) and the both Yin-Yang Deficiency type (D). Their insulin sensitivity were examined and compared with that of 40 healthy subjects. RESULTS: (1) Compared with healthy subjects, all hypertensive patients had apparent insulin resistance (P < 0.05). If the insulin sensitivity of healthy subjects was defined as 1, that of patients of type A, B, C and D were 0.54, 0.58, 0.65 and 0.80 respectively. (2) Comparison between the insulin sensitivity of type A, B and C showed no significant difference, while they were compared with type D, the difference was significant (P < 0.05), that is, the insulin sensitivity of type D was close to that of healthy subjects. (3) The fasting blood insulin of type D was obviously lower and the insulin sensitivity of type D was obviously higher than that of the other three types (P = 0.0001). (4) After adjusting age, sex and body mass indexes, multivariate regression analysis demonstrated that insulin sensitivity was closely correlated with SDT (P = 0.0001). CONCLUSION: Insulin resistance is one of the pathological basis for SDT in hypertension.

Adult↗
PubMed1999

[Effect of mecobalamin on diabetic neuropathies. Beijing Methycobal Clinical Trial Collaborative Group].

OBJECTIVE: To investigate the effect of mecobalamin on diabetic neuropathies. METHODS: One hundred and eight patients with non-insulin dependent diabetes mellitus were involved in a randomized positive-control clinical trial. 62 cases were treated with mecobalamin 500 microg intramuscularly three times a week for four weeks then followed by 500 microg orally three times a day for additional eight weeks. 46 cases were treated with vitamin B(12) in the same way and served as controls. RESULTS: Twelve weeks after the treatment, spontaneous pain and numbness of limbs were improved by 73% and 75% in the mecobalamin group, which were much higher than those in the controls (36% and 45% respectively). Hypoesthesia, hotness, coldness, oral dryness and dysuria showed better response in the mecobalamin group than in the controls (55% vs 25%, 52% vs 18%, 59% vs 30%, 53% vs 19%, 63% vs 20% respectively). Mecobalamin also benefited nerve reflection and conduction velocity to a certain extent. No obvious side effects were found. CONCLUSION: Mecobalamin might be worthy of use as a safe agent in the treatment of diabetic neuropathies.

Administration, Oral↗
PubMed1999

[The etiology of impotence in 327 diabetic male adults].

OBJECTIVE: To investigate the etiology of impotence in diabetic male adults. METHODS: 327 diabetic men aged 20 - 70 years were interviewed; 129 (39.6%) of them complained of impotence. All the 129 patients were initially evaluated by diabetologists and then underwent psychosexual assessment by psychiatrists. In addition, evaluation for retinopathy, neuropathy, vascular disease and sex hormone level was carried out. RESULTS: The 327 diabetic patients were divided into four age ranges 25 - 34, 35 - 44, 45 - 54, and 55 - 70. The frequency of diabetic impotence in these groups was 9.7%, 34.2%, 48.0%, 62.7% respectively. Neuropathy was found in 79 (61.2%), psychogenic factor contributed in 66 (51.2%), vascular factor was present in 31 (24.0%), leakage of penile venous cavernosa occurred in 5 (3.9%), and treatment with impotence- related medications was the contributing factor in 2 (1.6%). There are significant differences of glycosylated hemoglobin, peripheral neuropathy, autonomic neuropathy, and proliferative retinopathy between impotent and potent diabetic patients. The degree of psychological problem is more serious in the diabetic impotent patients than in potent patients according to Minnesota multiphasic personality inventory (MMPI) test. No significant difference was found in smoking, alcohol and plasma testosterone level. CONCLUSION: The etiology of diabetic impotence is multifactorial. Neuropathy is the main cause, but vascular and psychological factors also contribute to it significantly.

Adult↗
PubMed1999

[A study on the endotoxin and bacterial contamination in reverse osmosis water and dialysis fluids].

OBJECTIVE: To evaluate the endotoxin (ET) and the bacterial contamination in reverse osmosis (RO) water and dialysis fluids for hemodialysis treatment. METHODS: Specimens of RO water and dialysis fluids were obtained at random from 18 hospitals in Beijing. ET was measured with chromogenic limulus amoeboeyte lysate (LAL) assay. Bacteriologic samples were processed on heterotrophic plate count agar with pour plate technique. The plasma IL-1, IL-6 and TNFalpha were tested with enzyme-linked immunosorbent assay (ELISA). RESULTS: The level of ET in RO water was 0.116 +/- 0.063 EU/ml, and the culture of bacteria had 2 positive results, both counting 100 CFU/ml. The level of ET was much higher in acid concentrate (Protocol B) than in basic concentrate (Protocol A). The culture of bacteria had 11 positive results in Protocol B concentration with 8 samples equal or higher than 2,000 CFU/ml. The culture of bacteria had only 3 positive results in Protocol A concentration, all being lower than 2,000 CFU/ml. Another investigation showed that the level of ET in dialysis inlet was higher than 0.5 EU/ml in 5 cases of a total of 16. Their plasma IL-1 and TNFalpha levels were significantly increased. CONCLUSION: Both ET and bacterial contamination exist in RO water and dialysate. It is essential to examine the level of ET and perform bacterial culture, as well as to disinfect RO and dialysate tank at regular intervals in order to reduce pyrogenic reactions.

Endotoxins↗
PubMed1999

[Electron microscopic studies on pathogenesis of idiopathic pulmonary fibrosis].

OBJECTIVE: To observe ultrastructural changes and study the pathogenesis of idiopathic pulmonary fibrosis. METHODS: The clinical manifestations in 9 patients with idiopathic pulmonary fibrosis were selected. Transbronchial lung biopsy materials were obtained for light microscopic and electron microscopic examination. RESULTS: The major morphologic changes were as follows: histologically, alveolar inflammation and interstitial fibrosis were observed. electron microscopic findings were: 1. alveolar type I cells were degenerated, broken-down and desquamated, endothelial cells were swelled, with inter cellular tight junction shortened, alveolar type II cells hyperplastic, basement membrane thinned and deformed; 2. alveolar macrophages and interstitial macrophages were hyperplastic; 3. mast cells were infiltrated and degranulated; 4. electron-dense deposits were present at alveolar wall; 5. myofibroblasts, fibroblasts, collagen and basement membrane like material were hyperplastic. CONCLUSIONS: Electron microscopic observations show that the alveolar epithelial cells, endothelial cells and basement membrane are all injured, interstitial macrophages hyperplasia, mast cells infiltration and degranulation, electron-dense deposits at alveolar wall are present. These morphologic changes provide basis for formation of idiopathic pulmonary fibrosis.

Adult↗
PubMed1999

[A clinical study on vaccine of Mycobacterium vaccae in treating pulmonary tuberculosis].

OBJECTIVE: To study the effect of vaccine of Mycobacterium vaccae on cell-mediated immunity and on treating patients with pulmonary tuberculosis. METHODS: Seventy cases of pulmonary tuberculosis with smear positive and initial treatment were classified randomly into group I (35 cases) and group II (35 cases), receiving 2HRZS/4HR and 2HRZS/4HR plus vaccine of Mycobacterium vaccae regimens respectively. Thirty-one multi-drug resistant pulmonary tuberculosis cases were classified into group III, receiving 4 - 6 sensitive antituberculous drugs and vaccine of Mycobacterium vaccae. Improvement of clinical symptoms, resolution of pulmonary lesions, negative conversion of sputum and changes of immunological functions were observed. RESULTS: No significant difference in improvement of symptoms was found in group I and group II (P > 0.05), and the improvement rate of clinical symptoms in group III was found more than 50%. X-ray resolution rates in 4th month were 83% and 89%, and cavity reducing rates 40% and 50% respectively in group I and group II, and no significant differences were found (P > 0.05). X-ray resolution rate was 29%, cavity reducing rate 7% and no deteriorated case was found in group III. Sputum negative conversion rates in 1st, 2nd, 3rd and 4th month were 23%, 51%, 83% and 97% respectively in group I, while 31%, 77%, 89% and 100% in group II, and 3%, 16%, 29% and 32% in group III. Significant difference was found between group I and group II in sputum negative conversion rate in 2nd month after treatment (P < 0.05). After treatment, values of lymphocyte transformation test (LTT), CD(3), CD(4) and CD(4)/CD(8) of the above 3 groups were all higher than that before the treatment (P < 0.05), level of tumor necrosis factor decreased in group II and IL-2, IL-6 increased in group III. CONCLUSIONS: Vaccine of Mycobacterium vaccae is a good immunotherapy preparation, which promotes sputum negative conversion and activation of cell-mediated immunity.

Adolescent↗
PubMed1999

[Extensive transbasal approach for removal of tumours in the nasal, sphenoid and clival regions].

OBJECTIVE: To improve operative results of removal of the tumors in midline cranial base and the reconstruction of defect at frontal base through modification of the operative approach and techniques. METHODS: Extensive transbasal approach was used in 15 patients with tumours in the nasal, sphenoid and clival regions. RESULTS: The tumor was removed in 10 patients, near totally removed in 4 and partial removed in 1. The operative results of all patients were excellent except an elderly patient with mild operative morbidity. CONCLUSIONS: The procedure we used expand the operative indications for the tumors situated at the midline cranial base and improve the operative results. The procedure has advantages such as wide operative space, reliable reconstruction of the frontal base, and no severe complications.

Adult↗
PubMed1999

[The proper opportunity of surgery for rectal cancer after preoperative adjuvant chemotherapy].

OBJECTIVE: To discuss the proper opportunity of surgery for rectal cancer after preoperative intra-arterial chemotherapy. METHODS: Preoperative chemotherapy was performed on 27 rectal cancer cases at Dukes stage B and C. The therapy comprised of arterial infusion of 5-fluorouracil 600 mg/m(2), mitomycin 15 mg/m(2) and epirubicin 30 mg/m(2) for one course. Miles' or Dixon's operation was carried out 7 to 10 days later. The effects of chemotherapy were evaluated. Dynamic changes of proliferating cell nuclear antigen (PCNA) expression were studied by immunohistochemistry on paraffin-embedded sections. RESULTS: Hematochezia was remitted in 19 cases. Histologically, the effects of chemotherapy were considered as slight, moderate and marked in 9, 15 and 3 cases, respectively. Side effects were slight and recovered in 4 days. There was a high expression of PCNA in rectal cancer. On the 7th to the 10th day, proliferating index was significantly higher than that of before chemotherapy (46.48 +/- 10.62)%, P < 0.05. CONCLUSIONS: Preoperative adjuvant chemotherapy plays a role in the treatment of resectable rectal cancer. It is suggested that radical surgery should be carried out 5 to 6 days after intra-arterial chemotherapy.

Adult↗
PubMed1999

[Treatment of complex crainocervical junction malformation by transoccipito-cervical posterolateral approach].

OBJECTIVE: To report the treatment of six patients suffering from complex craniocervical junction (CCJ) malformation by transoccipitocervical posterolateral approach which is a new surgical method. METHODS: Transoccipitocervical posterolateral approach was confirmed feasible by anatomy of the body. Diagnosis was made sure CT-three dimensional image and MRI for every patient. All cases reaived odontoidectomy and suboccipital decompression and/or bone graft. RESULTS: All patients showed favorable outcome without deterioration or recurrence. Six patients were followed up for 15 - 10 months. All patients showed marked progressive improvement of neurological disturbances and three of them resumed work half a year after operation. CONCLUSION: Transoccipitocervical posterolateral approach is a new surgical procedure by which anterior and posterior decompression of foramen magnun aria and bone graft (posterior craniocervical stabilization) could be fulfilled during one operation.

Adult↗
PubMed1999

[Surgical treatment of truncus arteriosus in children].

OBJECTIVE: To summarize the surgical results of truncus arteriosus in children. METHODS: Five patients with persistent truncus arteriosus underwent complete repair of truncus arteriosus. Type I was found in 2 patients, type II in 2 and type IV in 1 according to Collett and Edwards. Their ages ranged from 3 to 12 years (mean 6.3 years). The time of pulmonary circulation and evacuation of the pulmonary artery was not significantly prolonged. Complete repair was via a median sternotomy utilizing hypothemia with cardiopulmonary bypass, entailing separation of the pulmonary arteries from the truncus, repair of the resultant defect in the aorta, ventricular septal defect (VSD) closure with a patch in which the interrupted pledget-supported suture was placed in the truncal valve annulus of the superior border of VSD, and restoration of right ventricular outflow tract (RVOT) continuity utilizing extra cardiac conduits, of which autologous pericardial valved dacron conduit was used in 4 patients and homograft conduit in 1. RESULTS: Postoperative mean pulmonary pressure decreased significantly in all patients (P < 0.01) and the pressure gradient across conduit was 7 - 35 mm Hg. Two patients died immediately after the operation, which was not associated with pulmonary vascular lesion. Among 3 survivors, I had low cardiac output and respiratory dysfunction after operation and the others recuperated uneventfully. Survivors were followed up for a period of 114, 96 and 34 months respectively, and were all in NYHA functional class I. One died of occlusion of conduit 8 years after operation. CONCLUSIONS: Children with truncus arteriosus are still indicated for complete correction. Autologous pericardial valved dacron conduit has excellent long-term outcomes. Correcting truncal valve insufficiency, repairing VSD, avoiding large pressure gradient across conduit and shortening CPB time are keys to improve the survival rate of patients and achieve excellent long-term outcome.

Bioprosthesis↗
PubMed1999

[The study of ultrastructure of retinal pigment epithelium of transplantation].

OBJECTIVE: To investigate the ultrastructure of retinal pigment epithelium (RPE) for the base of clinical application. METHODS: Pigmented rabbit RPE was transplanted to the subretinal space of 10 unpigmented rabbits by internal route. The ultrastructure of transplanted RPE cells were observed by electron microscopy. RESULTS: The transplantation of RPE was successful. It was shown that the transplanted cells had polarity and attached to Bruch's membrane to form basal infoldings, and the relationships between transplanted cells and the host photoreceptors were also seen. CONCLUSIONS: The internal approach is a practical and useful method for transplantation of RPE. The transplanted RPE can vitalize, perform metabolism and form some normal ultrastructure.

Animals↗
PubMed1999

[An analysis of nutritional and harmful components of vegetables grown in plastic greenhouses].

OBJECTIVE: To study the changes in nutritional and harmful components of vegetables grown in plastic greenhouses. METHODS: In plastic greenhouses, microclimate and air concentrations of carbon monoxide, carbon dioxide, fluoride and respirable particulate were measured, and chlorophyll, total sugar, crude fiber, nitrite, fluoride, arsenic and some mineral elements in vegetables were determined as compared with those grown in the open-air fields. RESULTS: Greenhouse appeared a lower wind speed and darker illumination. Contents of chlorophyll a an b, total chlorophyll, reduced vitamin C, crude fiber in vegetables grown in greenhouse all were lower than those grown in open-air fields. Contents of potassium, calcium, magnesium, iron, zinc, copper and phosphorous were all lower in the vegetables grown in greenhouse than those grown in open-air fields. The contents of chlorophyll reducing Vitamin C. CONCLUSION: Lower wind speed and inadequate illumination in greenhouse affected photosynthesis and uptake of water in vegetables causing changes in their nutritional components. But, no contamination of burning coal was found in vegetables grown in greenhouse.

Air Pollutants↗
PubMed1999

[Epstein-Barr virus infection and expression of T-cell intracellular antigen-1 (TIA-1) in intestinal T-cell lymphoma].

OBJECTIVE: To study the status of Epstein-Barr virus (EBV) infection and the expression of TIA-1 antigen in 24 cases of intestinal T-cell lymphomas. METHODS: In situ hybridization for EBER1/2; immunohistochemical staining by three step ABC technique for TIA-1, LMP-1, CD30, CD45RO, CD3 AND CD20. 19 cases of intestinal B-cell lymphomas were used for comparison. RESULTS: (1) Of the 24 intestinal T-cell lymphoma cases, 23 were pleomorphic, medium to large cell type, and one cases was small cell type; in 20 of the 24 cases EBER1/2 signals were detected in the tumor cells; in 4 of the 20 EBER1/2 positive cases, tumor cells expressed LMP-1; EBER1/2 was not detected in 19 cases of intestinal B-cell lymphomas. (2) in 23 of the 24 cases, TIA-1 was expressed in most tumor cells, but not in the only case of small cell type; TIA-1 was negative in tumor cells of all 19 cases of intestinal B-cell lymphomas. CONCLUSIONS: A high level of EBV infection was present in this group of intestinal T-cell lymphomas, the expression of TIA-1 may be related to its cell origin. Intestinal T-cell lymphoma may be an EBV-associated extranodal NK/T cell lymphoma.

Adolescent↗