Biomedical subjects

C Li

Publications and source records attributed to C Li.

At least 415 records · Page 23Linked to original sources

PubMed2000

[Two-phase linear models of leaf emergence at different tillering positions in wheat and effects of different varieties and sowing dates].

Dynamics of leaf emergence shows the development progress and its relationship with growth in wheat. It was found that two-phase linear model equations (phase I faster than phase II) divided by glum differentiation stage could describe leaf emergence progress in relation to growing degree days (GDD) after sowing in wheat. This pattern was consistent in main stems and tillers of normal development with both winter-and-spring type varieties. The beginning of phase II shifted to an earlier development stage on main stems of winter type varieties of early planting (EP, September 30) and late planting (LP, March 2), and on T3 of both varieties of EP, MP (middle planting, on October 30) and LP due to their abnormal development. The thermal rate of leaf emergence on main stem was relatively high and steady during development for winter type variety of MP, and quickened with the postponing of sowing for spring type variety. The above results illustrated the difference of leaf emergence at different tillering positions, and the biological characteristics affected by different varieties and sowing dates.

Germination↗

PubMed2000

A large scale epidemiological survey of Graves' disease in Daqing area.

OBJECTIVE: To study the incidence of Graves' disease and the associated factors. METHODS: Totally 100,123 people aged 15 to 79 years in Daqing area were surveyed epidemiologically. The investigation was conducted for two years. RESULTS: All 301 patients with Graves' disease were first diagnosed, with 74 (1.6@1000) males and 227 (4.1@1000) females. The total incidence was 3.0@1000, showing significant differences between ages and between occupations. Investigation of 18 associated factors for Graves' disease by using the logistic multivariate regression analysis showed the pathological factors of the virus infection history, psychological stimulation, food, drugs, family history, education and distribution. CONCLUSION: This study may suggest the theoretical evidence for prevention and treatment of Graves' disease.

Adolescent↗

PubMed2000

Relationship between metabolic phenotype of N-acetylation and bladder cancer.

OBJECTIVE: To study the relationship between metabolic phenotype of acetylation and bladder cancer. METHODS: Totally 203 healthy volunteers and 67 patients with bladder cancer were investigated with caffeine as a metabolic probe. Urine samples were collected in 2-6 hours after a cup of 140 mg coffee was taken, and the caffeine metabolites, 5-acetylamino-6-formylamino-1-methyluracil (AFMU) and 1-methylxanthine (1X) were analyzed by high performance liquid chromatography (HPLC). The frequency histogram and probit plot were constructed to select the critical value which was used to assess slow and fast acetylation status both in healthy volunteers and patients with bladder cancer. RESULTS: The peak height ratios of AFMU and 1X (AFMU/1X) were from 0.06 to 6.50 for healthy volunteers and 0.10 to 6.31 for patients with bladder cancer, both with the critical value of 1.10. Of 203 healthy volunteers involved in this study, 26.3% were slow acetylacors, as compared to 46.3% with slow acetylacors in patients with bladder cancer. The odds ratio is 2.376, and the gene frequency for healthy volunteers and patients with urinary bladder cancer were 0.5218 and 0.6804, respectively. CONCLUSIONS: N-acetylation status in the Chinese population is polymorphic and completely concordant with that determined with other metabolic probes. Slow acetylators are significantly associated with bladder cancer.

Acetylation↗

PubMed2000

Oral mucosal conditions and some related factors in 140 Uygur centenarians.

OBJECTIVE: To investigate the condition of the oral mucosae in Xinjiang Uygur centenarians and explore some related factors. METHODS: The oral mucosae and mucosal exfoliative cells of 140 Xinjiang Uygur centenarians were examined. Saliva and blood were collected from some centenarians. Salivary immunoglobulins (IgA, IgM, IgG), complements (C3 and C4), nitrous oxide (NO), 10 trace elements, serum sex hormones, thyroid hormones and osteocalcin (OST) were analysed using immunoglobulin, complement and NO kits, an ionochromatophotometer, and the kits for sex hormones and thyroid hormones, and fluorescence enzyme-linked immunosorbent assay, respectively. RESULTS: Most centenarians (64.29%) had normal labial, buccal, palatal and gingival mucosae. The abnormal changes in mucosae were mainly vascular nevus patches and senile plaques. Their mucosal exfoliative cells showed similar characteristics to those in elderly Han. The centenarians who had normal mucosae had higher level of the trace element molybdenum (Mo) in their saliva than who had abnormal mucosae (P < 0.01). CONCLUSION: The oral mucosal condition of Uygur centenarians was generally good. The abnormal changes in oral mucosae of the centenarians were lesions not harmful to health and may be related to the lower level of Mo in their saliva.

Aged↗

PubMed2000

Platelet-derived growth factor and basic fibroblast growth factor immunolocalized in proliferative retinal diseases.

OBJECTIVE: To study the role of platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF) in the development of proliferative vitreoretinopathy (PVR). METHODS: Immunohistochemical localization was performed on frozen sections of the epiretinal or subretinal membranes from 21 PVR patients using! monoclonal antibodies against PDGF and bFGF and the streptavidin peroxidase system. RESULTS: PDGF was expressed in 15 of 21 specimens (71.4%), and bFGF was expressed in 14 specimens (66.7%). Different cell density was seen in different types of epiretinal membranes. The cell density of vascular membranes induced by PDR and Eales disease was the highest (> or = 61 cells/field, x 1000); nonvascular membranes induced by PVR or traumatic PVR had moderate cell density (31-60 cells/field); and the macular membrane had the lowest cell density (< or = 30 cells/field). CONCLUSION: The presents of PDGF and bFGF in PVR tissues suggest that PDGF and bFGF may play an important role in the development of PVR.

Epiretinal Membrane↗

PubMed2000

Mutation in the leucine-rich repeat of platelet glycoprotein Ib alpha results in defects in its interaction with immobilized von Willebrand factor under flow.

OBJECTIVE: To characterize effects of the GP Ib alpha mutation (A156V) on its interaction with von Willebrand factor (vWf) under high fluid shear stress. METHODS: The residue A156 of GP Ib alpha was converted to a valine and the mutant expressed in CHO cells expressing wild-type GP Ib beta and GPIX. The transfected cells were tested for their interaction with a panel of GP Ib alpha antibodies and for rolling on immobilized vWf under high shear. RESULTS: The mutation led to surface expression of a GP Ib alpha polypeptide that adopted a different conformation at its N-terminus because binding of the GP Ib alpha antibody AN51, which has a binding epitope in the N-terminal 35 residues, was eliminated, whereas binding of the others (AK2, MB45, and SZ2, all of which bind to regions C-terminal to the AN51 epitope) was normal. Mutant-expressing cells could adhere and roll on immobilized vWf under high fluid shear stress and rolled significantly faster than wild-type cells. CONCLUSION: These studies demonstrate that the mutation A156V results in a conformation change at the N-terminus of GP Ib alpha, which leads to an increase in the dissociation rate of the bond between the GP Ib alpha mutant and vWf.

Animals↗

PubMed2000

[Study on apoptosis and its related genes in pregnancy induced hypertension].

OBJECTIVE: To investigate apoptosis and its related genes expression in serious pregnancy induced hypertension (SPIH). METHODS: 40 cases of normal term pregnancy(NTP) and 40 cases of SPIH were enrolled in this study. Apoptosis was detected using DNA in situ terminal deoxynucleotidyl transferas (TDT)-mediated deoxyuridine triphosphate (dUTP)-biotin nick ending labeling (TUNEL); bax and bcl-2 were detected by immunohistochemical staining (SP). RESULTS: In NTP group apoptosis index(AI) of cytotrophoblasts(CT) and syncytiophoblasts(ST) in placenta was (1.1 +/- 0.9)% and (41.8 +/- 1.5)%; bax positive rate was (1.0 +/- 0.9)% and (28.9 +/- 9.7)%; bcl-2 was (2.2 +/- 0.8)% and (22.9 +/- 0.7)% respectively; bax/bcl-2 was 0.7-1.7. In SPIH group, AI was (4.3 +/- 1.2)% and (45.3% +/- 1.4)%; bax was (2.2 +/- 0.8)% and (42.5 +/- 11.7)%; bcl-2 was (3.2 +/- 0.8)% and (23.3 +/- 7.8)%; bax/bcl-2 was 1.0-3.2. The difference between SPIH and NTP was significant respectively (P < 0.01); bax/bcl-2 was balance in NTP, while the balance was broken in SPIH. CONCLUSIONS: Apoptosis and its related genes expression are simultaneous. The balance and imbalance of apoptosis and bax/bcl-2 affect the structure and the function of placenta, and then may further affect the outcome of pregnancy.

Adult↗

PubMed2000

[Fibronectin induces matrix metalloproteinase-2 expression in ovarian cancer cells].

OBJECTIVE: To investigate the effects of extracelluar matrix proteins on matrix metalloproteinases (MMPs) expression by cancer cells, and the underlying mechanisms. METHODS: Following stimulation of SKOV3 ovarian cancer cells by fibronectin, MMPs secretion and cellular mRNA contents were assayed by gelatin-zymography and RT-PCR, respectively. The activity of MMP-2 promoter was monitored by cellular luciferase activity after the cells were transfected with MMP-2 promoter-luciferase construct. Cellular p53 contents were determined by Western blot analysis. RESULTS: Fibronectin (5 micrograms/ml) was found to stimulate the secretion of MMP-2 but not MMP-9 by SKOV3 cells. The stimulation was enhanced with the increase in fibronectin concentration. When SKOV3 cells were treated with 10 micrograms/ml fibronectin for 1 hr, the cellular MMP-2 mRNA dramatically increased. However, with increase in stimulation time, MMP-2 mRNA content decreased. Fibronectin induced an increase in luciferase activity in cells transfected with MMP-2 promoter construct, whilst curcumin (50 mumol/L), a potent transcription factor AP-1 inhibitor, could not block the fibronectin-induced increase in MMP-2 promoter activity. Fibronectin also induced an increase in p53 content of SKOV3 cells. CONCLUSION: Fibronectin stimulates ovarian cancer cells to secret MMP-2 via its enhancing effect on MMP-2 promoter activity with resultant increase in MMP-2 transcription. The effect might involve a pathway associated with p53 but independent of AP-1.

Female↗

PubMed2000

[Study on respiratory impedance of patients with extratracheal tumour].

OBJECTIVE: To determine the manifestation of impulse oscillometry (IOS) in variation of respiration impedance on patients with extratracheal tumour. METHODS: The IOS indices in 30 normal persons and 28 patients with extracheal tumour were measured. The ratio of forced expiratory volume after 1 second to forced vital capacity (FEV1/FVC) was evaluated and the maximal expiratory flow-volume curve (MEFV curve) was examined. The above values with t-test of SPSS statistics software were analyzed. RESULTS: Compared with the normal group, in the extratracheal group the ratio of actual value of resistance to the predict from 20 Hz to 35 Hz increased obviously and this only occurred with the reactance at 20 Hz (P < 0.01). The resistance curve showed clear rise after the 20 Hz and the reactance curve peaked at 20 Hz and was leveled to normal at 35 Hz. CONCLUSION: IOS is capable of presenting the distinctive indices for the study of respiration impedance on patients with extratracheal tumour.

Electric Impedance↗

PubMed2000

[Prevalence of cag A and vac A subtypes of Helicobacter pylori in Guangzhou].

OBJECTIVE: To investigate the prevalence of cytotoxin associated gene (cag A) and vacuolating cytotoxin gene (vac A) subtypes of Helicobacter pylori (Hp) from patients with upper gastrointestinal diseases in Guangzhou, and to assess the relationship between cag A, vac A subtypes and Hp related gastrointestinal diseases. METHODS: 191 Hp strains were isolated from patients with different gastrointestinal diseases in Guangzhou. Bacterial DNA from all these strains was extracted. cag A and vac A alleles were typed using PCR with specific primers. RESULTS: In Guangzhou, Hp cag A positive rate was 85.3% (163/191). cag A positive rate was significantly higher in gastric cancer and peptic ulcer than that in chronic gastritis (P < 0.05). There were six vac A mosaicisms, including 168 for s1a/m2 (88.0%), 14 for s1a/m1b (7.3%), 6 for s1b/m2 (3.1%), 1 for s1b/m1b (0.5%), 1 for s2/m2 (0.5%) and 1 for s1a/m1b-m2 (0.5%). The rate of vac A s1a/m2 subtype in chronic gastritis, peptic ulcer and gastric carcinomas was 87.5% (70/80), 87.5% (84/96) and 93.3% (14/15) respectively. There was no significant relationship between cag A and vac A subtypes (P > 0.05). CONCLUSION: cag A(+) and vac A s1a/m2 subtype of Hp is predominant in patients with upper gastrointestinal diseases in Guangzhou, cag A(+) strains are further more common in patients with gastric cancer and peptic ulcer.

Adolescent↗

PubMed2000

[Clinicopathologic study of patients with small cell carcinoma of the cervix].

OBJECTIVE: To study the clinicopathologic characteristics, diagnosis and treatment of small cell carcinoma of the cervix. METHODS: Eight patients with small cell carcinoma of the cervix were treated from May 1991 to December 1997 at Jiangxi Women's and Children's Hospital. Clinical data and follow-up records were retrospectively analyzed. RESULTS: Five patients had stage I(b) disease and 3 had stage II(b) disease. Seven patients underwent radical hysterectomy with pelvic lymph node dissection. One patient with stage II(b) disease was only treated with radiotherapy. Of the patients treated with operation, three showed pelvic lymph node metastases. Four patients who are alive free of the disease have been followed for 2, 13, 16 and 25 months, respectively. The survival intervals of 4 patients who died of the disease was 4, 5, 7 and 10 months, respectively. Of the death, one patient was only treated with radiotherapy, another had a very large cervical tumor and the two others complicated with pelvic lymph node metastases. CONCLUSIONS: Small cell carcinoma of the cervix is an aggressive tumor with a potentiality for early pelvic lymph node metastases and rapid recurrence, It is associated with higher mortality than any other cervical malignant neoplasms. It is able to make a right diagnosis with a combination of histopathologic and immunohistochemical characteristics.

Adult↗

PubMed2000

[Lung cancer: new staging system and prognosis].

OBJECTIVE: To evaluate the rationality the revised international system for staging lung cancer and its relationship with prognosis. METHODS: Between January 1961 and December 1988, 946 patients were subjected to removal of lung cancer and the data were analyzed using life-table, Log-rank test, and Cox regression model. Twenty-nine prognostic factors influencing the survival rate were evaluated with SAS6.12 software. The survival rate was calculated according to the two different staging systems. The revised system for staging lung cancer was evaluated. RESULTS: The factors influencing prognosis after surgical treatment of lung cancer were as follows: P-TNM staging, metastatic lymph nodes, radical or palliative resection, tumor size, and different cell types. The 5-year survival rate of patients with stage IA, IB, IIA, IIB, IIIA, IIIB was 68.4%, 59.5%, 44.8%, 36.5%, 26.3%, and staging 24.8%, respectively (IIIA and IIIB P > 0.05; other stages P < 0.05). CONCLUSIONS: The revised system for lung cancer is more rational and objective to estimate prognosis and direct treatment. But it should be revised further.

Adult↗

PubMed2000

[Predictive factors for successful sperm recovery in azoospermia patients].

OBJECTIVE: To find any predictive factors for successful testicular sperm recovery in azoospermic patients. METHODS: 50 cases of azoospermia were subjected to testicular biopsy. Serum follicle stimulating hormone (FSH), concentration, testicular volume, testicular histopathology, and testicular sperm extraction (TESE) were determined in each cases. RESULTS: Neither serum FSH values nor testicular volume were predictive of spermatozoa in TESE. Testicular histopathology was specific for predicting successful sperm recovery (sensitivity 96%; specificity 100%; accuracy 100%). CONCLUSIONS: Azoospermia patients with high FSH and small testis should be recommended for testicular biopsy and TESE to confirm if there is any testicular spermatozoa.

Adult↗

PubMed2000

[Analysis on genetic pattern of familial type II diabetes mellitus].

OBJECTIVE: To analyse hereditary familial type II diabetes mellitus (type II DM), including its pattern and the transmitted expression on different sex of type II DM. METHODS: Familial analysis, segregation analysis, tests were used for multifactorial inheritance and threshold analysis. One hundred seventy-seven pedigrees of familial type II DM were studied. RESULTS: The heritability of familial type II DM was 143.06% +/- 3.3%. One dominant major gene might influence the genesis of type II DM. There were 214 nuclear families in 3 different mating types: U x U, U x A and A x A. The segregation ratios of U x U, U x A and A x A were 0.4703, 0.4838 and 0.6712 respectively. The results of tests for multifactorial inheritance and segregation analysis indicated that the genetic pattern of U x A and A x A nuclear families was not multifactorial inheritant and autosomal recessive (AR) but autosomal dominant (AD) inheritance. The genetic pattern of U x U nuclear families was neither AD nor AR inheritance. CONCLUSION: There was genetic heterogeneity in type II DM discovered with subgroupes of autosomal dominant inheritance in type II DM.

Adult↗

PubMed2000

[The significance of the expression of the HSP70 and HSP90 in the intestinal mucosa in scalded rats during early postburn stage].

OBJECTIVE: To investigate the changes in the expression, the tissue contents and the distribution of heat shock protein (HSP) 70 and HSP90 in the intestinal mucosa in scalded rats during early postburn stage and to elucidate the effects of heat shock response of intestinal mucosal cell on burn victim's systemic pathophysiology. METHODS: The scalded rats were taken as the model. ELISA, immunoblotting analysis and immunohistochemical methods were employed to analyze and study the expression, the tissue contents and the distribution and their functional status of HSP70 and HSP90 in the intestinal mucosa. RESULTS: (1) The free HSP70 content in the intestinal mucosa exhibited significantly transient decrease in the early postburn stage. (2) The total contents of HSP70 and HSP90 in the intestinal mucosa increased obviously postburn. (3) There exhibited remarkable heterogeneity of the molecular structure of HSP70 in the intestinal mucosa in the early postburn stage. CONCLUSION: The expression and the changes in the contents and the tissue distribution of the two HSPs in the intestinal mucosal cell might play important roles in the cellular stress reaction of the intestinal mucosa and even in the intestinal barrier functional mechanism.

Animals↗

PubMed2000

[Establishment and biological characteristics of a novel erythroleukemia cell line (HIE1)].

OBJECTIVE: To establish a novel leukemia cell line and characterize its biological characteristics. METHOD: The cell line was established by liquid cell culture. The genetic marker was analyzed by R-banding and reverse transcriptase-polymerase chain reaction (RT-PCR), cell morphology by microscopy, electron microscopy and histochemical staining, cell surface antigen by monoclonal antibody, hemoglobin by hyperomethemoglobin measurement and electrophoresis, erythroid differentiation by benzidine-staining, and monocyte-macrophage differentiation by cell morphology and phagocytosis. RESULTS: A novel erythroleukemia cell line (HIE1), with original cell genetic marker (Ph chromosome, bcr/abl fusion gene rearrangement), was established from a CML patient in blast crisis, and has been passaged for over 60 generations. Myelomonocyte marker and hemoglycoprotein A were found on the cell surface. HIE1 cells contained hemoglobin, the same HbA and HbA(2) bands as in normal individuals were displayed by Hb electrophoresis. The benzidine positive HIE1 cells were induced after exposure to 3.6 x 10(-4) mmol/L Ara-C. When HIE1 cells were treated with 100 ng/ml PMA for 3 days, one third of the cells became spindle in shape, and 6.5% of the cells exert phagocytosis. The cells were classified into two types with Wright-staining: one showing light blue cytoplasm and a few of cells with basophilic granules, the other showing dark blue cytoplasm with vacuoles and pseudopods without granules. In addition, POX, SB, CE stains were negative, and AE, PAS, ACP stains positive. Colony formation of the cells was 37%, the cell doubling time was 22 - 24 hrs, and EB virus detection was positive. CONCLUSION: A novel erythroleukemia cell line with bcr/abl fusion gene and characteristics of myelomonocytic and erythroid cells was established.

Cell Differentiation↗

PubMed2000

[Treatment of acute lymphoblastic leukemia by autologous stem cell transplantation: an analysis of 30 cases].

OBJECTIVE: To evaluate the clinical outcome of autologous stem cell transplantation (ASCT) in acute lymphoblastic leukemia (ALL) and the affected factors. METHODS: Data of 30 ALL patients received ASCT in our hospital between July 1987 and December 1997 were retrospectively analyzed. Twenty-four of them were in the first complete remission (CR(1)) and six in the second complete remission (CR(2)) or early relapse (ER). Conditioning regimens were CTX 120 mg/kg + single total body irradiation 9 - 10 Gy (sTBI) or Bu 16 mg/kg of Mel 140 - 180 mg/m(2) + Ara-c 2 - 4 g/m(2). RESULTS: All patients reconstituted hematopoiesis. The median follow-up duration was 504 (18-3043) days. Transplant-related mortality was 10%. The probabilities of 3 year disease-free survival (DFS) for ALL in CR(1) and CR(2) were 67.7% +/- 10.3% and 16.7% +/- 15.2%, respectively (P = 0.00547); the 3 year DFS was significantly better with posttransplant treatment than without it (92.3% +/- 7.4% vs 50.0% +/- 17.7%, P = 0.0130). CONCLUSION: Acute lymphoblastic leukemia patients without HLA-matched related donor are recommended for ASCT in CR(1). To reduce relapse and improve the outcome, adoptive immunotherapy or maintenance chemotherapy should be given after ASCT.

Adolescent↗

PubMed2000

[The impact of hepatitis B virus infected patients or donors on the outcome of hematopoietic stem cell transplantation].

OBJECTIVE: To investigate the impact of recipients and/or donors infected with hepatitis B on the outcome of hematopoietic stem cells transplantation (HSCT). METHODS: We analyzed retrospectively the transplantation outcome in 26 of 164 hematological diseases patients who and whose donors were infected with hepatitis prior to transplantation. RESULTS: (1) Three of the 26 patients developed VOD after HSCT, the incidence (11.5%) is significant higher than that in patients and donors who did not infected with HBV (P < 0.05). (2) Two of 5 patients transfused hematopoietic stem cells from HBsAg + donors developed hepatitis B. (3) Four patients with allogeneic stem cell transplantation developed hepatic failure (HF) which occurred during cyclosporin (CsA) being tapered off or withdrawal. The incidence of HF in patients and/or donors infected with HBV (15.4%) is obviously higher than that in patients and donors who did not (0.08%, P < 0.01). (4) In 4 patients with HbeAg +, 2 patients died of HF after allogeneic HSCT, the other 2 patients survived after autologous HSCT. CONCLUSION: Donors and recipients infected with hepatitis B are not contraindication of HSCT, but patients with allogeneic HSCT are in danger to develop LF during CsA being tapered off or withdrawal.

Adolescent↗