Search PubMed⌕ Search

Biomedical subjects

F Li

Publications and source records attributed to F Li.

At least 145 records · Page 8Linked to original sources

[Revision of thin-walled cystic bleb by transposing conjunctival flap technique].

OBJECTIVE: To investigate the clinical effect of transposing conjunctival flap technique on thin-walled cystic blebs after trabeculectomy for treatment of glaucoma. METHODS: Fifty-two eyes of 46 patients with thin-walled cytic blebs were underwent this modified operation. The procedure involved incising the conjunctiva surrounding the preserved bleb, then the conjunctiva-Tenon's fascia flap superior or temporal to the cystic bleb was relaxed and mobilized to cover the bleb surface after topical cryopexy. The anterior margin of the flap was sutured onto the peripheral cornea. In order to relax the conjunctival flap sufficiently, an incision was made close to the superior fornix above the flap and parallel to limbus to decrease the tension. RESULTS: In the follow-up of 6 months-4 years, the mean intraocular pressure (IOP) of 52 eyes increased to postoperative (12.98 plus minus 5.70) mm Hg from preoperative (4.25 plus minus 1.33) mm Hg (1 mm Hg = 0.133 kPa) (t = 3.26, P < 0.01), 51 eyes maintained the filtering function. Post-operatively, the bleb leakage in 20 eyes and macular edema in 6 eyes disappeared. Local antiglaucoma medication was required in one eye, because the bleb disappeared with increasing IOP. The post-operative visual acuities were elevated in comparison with that before the operation (chi(2) = 16.65, P < 0.01). CONCLUSION: The transposing conjunctival flap technique is an effective surgery for the repair of thin-walled cystic bleb whose complications, such as hypotony, maculopathy, bleb leakage or endophthalmitis can be cured or prevented.

Adolescent↗

[The relationship of clinicopathology and immunophenotypes in non-Hodgkin's lymphomas of the spleen].

OBJECTIVE: To investigate the relationship between clinicopathologic features and immunophenotypes in non-Hodgkin's lymphoma (NHL) of the spleen. METHODS: Clinicopathologic analysis and follow up; immunohistologic staining by SP method and EBER in situ hybridization. RESULTS: (1) Splenomegaly was found in all 19 cases of spleen NHL, 10 of the 19 (52.6%) cases had masses or a mass in their enlarged spleen; (2) 14 of the 19 (73.7%) cases were of B-cell type (including 5 cases of follicular type and 9 cases of diffuse type), in which 8 cases were centroblastic, 3 of centroblast/centrocyte and 4 cases of small lymphocyte types; all 10 cases of primary splenic lymphomas (PSL) were B-cell type; (3) 5 of the 19 cases (26.3%) had peripheral T-cell origin, including 4 cases of large cell type and 1 case of small cell type; of the 3 TIA-1 positive cases, 2 were also positive for EBER 1/2 (one CD 8+ and another CD56+), the remaining case was CD8-, CD56-, EBER1/2-; all 5 cases were secondary NHL of the spleen; (4) Follow up data were obtained for 14/19 cases (73.7%). 8 of 9 surviving cases were primary NHL. The range of survival period varied from 8 to 10 years. All 5 deceased cases had secondary NHL and their survival period was 2 to 6 months. CONCLUSIONS: Some relationship exists between the clinicopathology and origin of the tumor cells in splenic NHL, the prognosis of primary NHL is better than that of the secondary NHL and the diagnosis of primary NHL should be made with discretion.

Adolescent↗

[Cytotoxic natural killer/T-cell lymphomas of the lymph nodes].

OBJECTIVE: To investigate the clinicopathologic features of cytotoxic natural killer (NK)/T-cell lymphomas of the lymph nodes. METHODS: Clinicopathologic observations and follow up on 5 cases of cytotoxic NK/T-cell lymphomas of the lymph nodes, immunohistochemical staining for CD45RO, CD8, CD56, CD30, CD20, TIA-1 and in situ hybridization for EBER1/2 were performed. RESULTS: (1) The clinicopathologic features of cytotoxic NK-T-cell lymphomas of the lymph nodes were summarized; (2) The tumor cells were positive for CD45RO in 4 of the 5 cases, in which 3 cases were also positive for CD56. One case was of null cell type. The tumor cells were positive for TIA-1 and EBER1/2 in all 5 cases. CONCLUSIONS: The clinicopathological features and special immunophenotypes of cytotoxic NK/T-cell lymphomas of the lymph nodes were present in all 5 cases. Clinically, this entity tends to be an aggressive process with poor prognosis.

Adult↗

[Antimetastatic effects of arginine-aspartate on salivary adenoid cystic carcinoma in vitro].

OBJECTIVE: To test the effects of arginine-aspartate (RD) on metastasis of salivary cystic carcinoma (SACC). METHODS: Highly metastatic SACC cell line SACC-LM was used in the study. The effect of RD on tumor cell-ECM adhesion was assayed by MTT technique. The effect of RD on invasion and migration of SACC-LM were evaluated using modified boyden chamber. RESULTS: RD inhibited tumor cell fibronectin adhesion at 5 mg/L concentration, but no effects on tumor cell laminin and tumor cell type IV collagen adhesion. RD inhibited the invasion at 1, 5, 25 mg/L, and inhibited the migration only at 25 mg/L. CONCLUSIONS: The result shows that the RD has an antimetastatic effect on SACC-LM cells in vitro.

Antineoplastic Agents↗

[Expression of Fas and Fas ligand in lesions of patients with discoid lupus erythematosus].

OBJECTIVE: To study the relation of apoptosis and pathogenesis of lupus erythematosus. METHODS: Expressions of Fas and Fas ligand(FasL) were detected in 30 lesions of discoid lupus erythematosus(DLE) and 5 skin specimens from healthy controls by immunohistochemical staining. RESULTS: Fas and FasL were positively expressed in most epidermal keratinocytes, infiltrating lymphocytes around blood vessels and appendages, and Fas was positively expressed in a few sweat ducts and hair follicles. Fas and FasL expressions were weakly positive or negative in healthy controls. CONCLUSION: Apoptosis induced by Fas, FasL pathway may be related to the pathogenesis of lupus erythematosus.

Adult↗

[A study of the acting mechanism of aspirin for resistance to oxidative damage].

OBJECTIVE: To explore the mechanism of aspirin for resistance to oxidative damage in endothelial cells. METHODS: Using cultured endothelial cells, we measured the levels of aspirin induced ferritin expression on resistance to hydrogen peroxide toxicity toward cells in the presence of the iron chelator desferrioxamine added to FeCl3. RESULTS: Aspirin at low concentration (0.1 mmol/L) induced significant increase of ferritin expression in a time- and concentration-dependent fashion up to 25% over basal levels(P < 0.05). Preincubating the cells for 8 h with aspirin (0.1 mmol/L) reduced lactate dehydrogenase(LDH) release rate by 50%, toxicity reduction by 40%, and significant decrease of malondialdehyde (MDA) production. Aspirin induced cytoprotection from H2O2 damage was also in a concentration- and time-dependent fashion. However, in the presence of the iron chelator desferrioxamine, aspirin enhanced ferritin synthesis was abrogated, in contrast, FeCl3 increased aspirin induced ferritin synthesis in cells. CONCLUSION: The study suggested that the antioxidation of aspirin was brought into action by affecting the cellular iron metabolism pathway to induce ferritin synthesis.

Antioxidants↗

[The study on the occult metastases to cervical lymph node in squamous cell carcinoma of the larynx and hypopharynx].

OBJECTIVE: To study the metastastic regularity of cervical lymph node in squamous cell carcinoma of the larynx and hypopharynx, which will provide some theoretical basis for surgeon to use selective neck dissection (SND) in some patients with carcinoma above. METHOD: Sixty-nine originally cN0 staged neck dissection specimens from 40 patients were evaluated using mutipl-level sectioning in 4 microns intervals, which were respectively processed by H&E-staining and immunostaining with an antibody to cytokeratin (CK AE3). These patients weren't given any treatment (radiotherapy or chemotherapy or surgery in neck) before surgery. All cases had been followed up 1 year or more. RESULT: The examination of lymph nodes from 40 patients revealed 31 (0.59% 31/2219) occult metastases in 14 (35% 14/40) patients. Among them, six patients with supraglottic cancer, 1 patient with transglottic cancer and 7 patients with hypopharyngeal cancer. There were no occult metastases to cervical lymph node among 9 patients with glottic cancer. All occult metastases mainly located in ipsilateral level II and/or level III. Occult metastases weren't found in nodes from level I, level IV and level V. CONCLUSION: The study further prove that metastases to cervical lymph node mainly occur in the ipsilateral level II and level III among patients with carcinoma of the larynx and hypopharynx. According to the risks of occurring occult metastases to cervical lymph node, we suggest applying to ipsilateral or bilateral SND (level II and level III be dissected) among patients with carcinoma of the larynx and hypopharynx which staged T2-T4 N0M0 clinically.

Adult↗

Simultaneous determination of sixteen phenylurea herbicides in water by high performance liquid chromatography and solid phase extraction.

A high performance liquid chromatography (HPLC) procedure for simultaneous determination of sixteen phenylurea herbicides in water is described. A Lichrospher 100 RP-18e column and spectrophotometric detection at 240 nm were used. Adequate retention was achieved with a mobile phase of acetonitrile/water solution with gradient elution. The HPLC analysis time was less than 20 min. The herbicides were isolated from water samples by using a single solid phase extraction procedure with C18 solid-phase columns. An enrichment factor of 1,000 was achieved. Recoveries were in the range between 87.8% and 103.7%. The detection limits of the whole procedure achieved were less than one-tenth of the maximum limit permitted by the European Community standard for drinking water.

Chromatography, Gas↗

[Isolation, purification and identification of metallothionein from strain BD102 of Hansenula anomala].

Metallothionein (MTs) in Cu and Cd resistant strain BD102 of Hansenula anomala were induced by administration of Cu2+ and Cd2+. These proteins were isolated and purified by Sephadex G-50 and subsequent DEAE-Sepharose CL-6B, then Sephadex G-25 for desalation. There were two isoform MTs by Cu(Cu-MTs), one form induced by Cd (Cd-MT). The molecular weights of the Cu-MTs and the Cd-MT were about 7 kD and 7.5 kD respectively. Exposure of Hansenula anomala to copper salts stimulated formation of two isoform Cu-MTs with a cysteine content of 6.6-6.8% and had 60 amino acids. Exposure of Hansenula anomala to cadmium, stimulated formation of Cd-MT with a cystein content of 10% was synthesized and had 61 amino acids. 4 atom Cu or Cd/mole MTs.

Amino Acids↗

[Purification and characterization of a DNA helicase from the hyperthermophilic archaeon Sulfolobus shibatae].

A DNA helicase from the hyperthermophilic archaeon Sulfolobus shibatae has been purified to homogeneity by column chromatography on Q Seqharose, phosphocellulose P11, heparin agarose, Superdex 200 and phenyl Superose. The purified enzyme shows DNA-stimulated ATPase activity. The molecular mass of the enzyme is approximately 63 kD. The S. shibatae DNA helcase is capable of unwinding a 70 bp duplex DNA flanked by unpaired single-stranded tails at both ends. The helicase activity requires Mg2+ and hydrolysis of ATP, and is inhibited by NaCl at concentrations greater than 200 mmol/L. It has an optimal pH of 6.7. The enzyme is active at temperatures between 40 and 80 degrees C, and the activity peaks at 70 degrees C. The S. shibatae DNA helicase is the first native DNA helicase to be isolated from archaea.

Adenosine Triphosphatases↗

[Cloning and sequencing of 16S rRNA gene of Phytoplasma CWB1 strain associated with cactus witches' broom].

A 1.5 kb DNA fragment was amplified in DNA samples extracted from Opuntia salmiana porm showed witches'-broom symptom. The result indicates the existence of phytoplasma associated with this disease and this phytoplasma was designated as CWB1. The amplified fragment was ligated to pGEM-T easy vector and then transformed into JM109 strain of E. coli. Cloned DNA fragments were verified by PCR, restriction endonuclease (EcoRI) digestion and sequence analysis. The result revealed that the 16S rRNA gene of CWB1 consists of 1489 bp and shared 99.7% homology with Faba bean phyllody which belongs to phytoplasma 16S rII-C subgroup. So we can classify this strain into phytoplasma 16S rII-C subgroup.

Cloning, Molecular↗

[Clinical and experimental study of effect of yangxin fumai oral liquid in treating patients with extrasystole].

OBJECTIVE: To evaluate the therapeutic effect of Yangxin Fumai Oral Liquid (YFOL), a Chinese herbal medicine for nourishing heart and restoring pulse, in treating patients with extrasystole. METHODS: The effect of YFOL was observed in treating 30 patients with different kinds of extrasystole and compared with that in 30 patients treated by propafenone. The effect of YFOL on experimental arrhythmia was studied in animals as well. RESULTS: Clinical observation showed that the effect of YFOL against extrasystole in the two groups was similar, but the YFOL group showed better effect in symptom improvement (P < 0.01) with no marked side-effects. Experimental study showed that YFOL could reduce the chloroform induced ventricular fibrillation occurrence in mice, delay the initiating time of ventricular extrasystole, tachycardia and fibrillation induced by aconitine, BaCl2 and coronary artery ligation in rats, or shorten the lasting time of arrhythmia, reduce the attacking rate of ventricular extrasystole. There was significant difference in comparing with the control group (P < 0.05, P < 0.01). CONCLUSION: YFOL is a good and convenient Chinese herbal preparation for different kinds of extrasystole with low toxic and side-effects in clinical practice.

Aconitine↗

[Relationship between apoptosis and expression of Fas, bcl-2 and Ki-67 in condyloma acuminatum].

OBJECTIVE: This study inquired into the significance and relationship of apoptosis to the regulation and proliferation of condyloma acuminatum(CA). METHODS: Apoptotic cells were detected in situ by terminal deoxynucleotidyl transferase-mediated-dUTP nick end labeling (TUNEL). The detection of Fas, bcl-2 and Ki-67 expression was performed using immunohistochemical staining in 28 specimens of CA. RESULTS: Apoptotic cells were found in 24 cases (85.7%) in keratinocytes. All of the in 28 cases(100%) had Fas and Ki-67 positive expressions, but only 8 cases (28.6%) had bcl-2 mild or moderate expression. The disease severity (serious, moderate and mild) groups did not significantly differ in apoptotic index (AI), Fas, bcl-2 and Ki-67 positive expression (P > 0.05). There was positive correlation between AI and Fas(r = 0.866, P = 0.000). bcl-2 and Ki-67 were negatively correlated with AI (r = -0.416, P = 0.018; r = -0.475, P = 0.006). CONCLUSION: It is suggested that apoptosis in keratinocytes may play an important role in inhibiting the proliferation of virus, that Fas may be an upregulative factor and bcl-2 may be an inhibition factor to apoptosis, and that excessive Ki-67 expression may be associated with the acceleration of cell cycle.

Adaptor Proteins, Signal Transducing↗

[Comparisons of two ultraviolet-vacuum ultraviolet radiation scales].

The ultraviolet-vacuum ultraviolet emission standards including high temperature argon wall-stabilized arc and synchrotron radiation were introduced. The spectral radiometric characteristics of an argon wall-stabilized arc and a deuterium lamp calibrated by synchrotron radiations were studied as ultraviolet-vacuum ultraviolet radiation scales. With the spectroradiometris system of high precision established by us, the comparison of scales between the argon wall-stabilized arc and the synchrotron radiations in the 165-300 nm range has shown agreement to within +/- 5%.

Argon↗

[On the characteristics of velocity modulation laser spectroscopy].

The technical properties of velocity modulation laser spectroscopy were investigated using the spectrum of A2 pi u-X2 sigma g+ (2-0) band of Meinel system of N2+. The dependence of spectral intensity on discharge current, the pressure of the gas mixture and the pump velocity of the vacuum pump were studied. Making uses of the results of these studies, the sensitivity and resolution of the spectrometer are improved by above 3 times, and economized the experimental expenses can be reduced to as 3/4 time as normal, which confirms that the results of this paper is of considerable uses.

Lasers↗

[Synthesis of nanocrystalline Y2O3:Eu3+ and study on spectral characteristics].

Nano-Y2O3:Eu3+ was synthesized with oxalic acid as precipitate agent while adding little surfactant controlling the condition of the reaction. We obtained nanoscale powder. The particle diameter was 15-19 nm. The agglomerate size was less 1.0 micron. Compared with the ordinary powder of Y2O3:Eu3+, the peak of emission spectrum of nano-Y2O3:Eu3+ is at lambda em = 612 nm under 254 nm excitation, blue-shift 6 nm. Excitation spectrum has no difference. The phosphor was measured by PMS-3 chromatic detector and its luminescent chromatic coordinate parameters were x = 0.6479, y = 0.3442. The quenching concentration increases from micro-Y2O3:Eu3+'s 6% to 9% and the intensity of luminescence increases with the grain size growing.

Crystallization↗

[Assignments of FIR-LMR spectra of CF X 2Pi (nu = 1) and MIR-LMR spectra of NO X 2Pi (nu = 1<--0)].

According to the theories of Zeeman effect and the principle of laser magnetic resonance (LMR), a method and model for the analysis of the laser magnetic resonance spectra were developed and successfully employed to assign the FIR-LMR spectra of CF X2 Pi (nu = 1) and the MIR-LMR spectra of NO X 2Pi (nu = 1<--0). This work provided an efficient and accurate approach for primary analysis of the LMR spectra of novel radicals.

English Abstract↗