Biomedical subjects

G Wang

Publications and source records attributed to G Wang.

At least 487 records · Page 27Linked to original sources

PubMed1998

[Detection of oncogenic mutations in sputum and its diagnostic value of lung cancer].

OBJECTIVE: To find a new method to molecular biological detection of lung cancer. METHOD: The sputum specimens from 96 cases of lung cancer and other lung patients were detected for K-ras and p53 mutations by using polymerase chain reaction(PCR) and restriction fragment length polymorphism and and immunohistochemistry (IHC) techniques. RESULT: 38 out of 62 sputum specimens of lung cancer patients were positive for cytology: Sensitivity was 61%. NPV (negative predictive value) was 59%; p53 was overexpressed in 48 cases: Sensitivity was 77%. NPV was 66%; k-ras was positive in 21 cases: Sensitivity was 34%, NPV 42%; The combination of conventional cytology and molecular screening(k-ras + p53) produced a sensitivity value of 92%(P < 0.05) with an NPV of 84%(P < 0.05); In 24 cases of patients whose cytology of sputum was false negative, 17 were found either p53 or k-ras positive of which 7 patients were identified to be lung cancer in the follow-up study. CONCLUSION: These results suggest that detection of oncogene mutation in sputum enhanced and added to the diagnostic value of conventional cytology. It is a promising approach to early lung cancer detection and massive screening in terms of its rapidity, economy and simplicity.

Adenocarcinoma↗

PubMed1998

[Determination of organic pollutants in water by off-line supercritical fluid extraction-Gas Chromatography/Infrared Spectrometry/Mass Spectrometry].

A supercritical fluid extraction (SFE) method using carbon dioxide for the determination of organic pollutants in Yellow River water was developed. In this paper, organic contaminants in 3 L Yellow River water were concentrated on 1 g GDX-301 adsorbent and then eluted from the adsorbent with supercritical CO2. The analytes extracted by SFE were collected into 1 mL alcohol collecting solvent through a SiO2 restrictor (35 cm x 50 microns i.d.). Finally, the collecting solvent was analyzed by Gas Chromatography/Infrared Spectrometry/Mass Spectrometry. The SFE conditions which were optimized for removal of the analytes from adsorbent were 20 MPa, 60 degrees C and 40 min. The extraction efficiencies of SFE were directly compared to those obtained by using 15 mL dichloromethane elution. Efficiencies of SFE under conditions of 20 MPa, 60 degrees C and 40 min were generally higher than those of solvent elution.

Gas Chromatography-Mass Spectrometry↗

PubMed1998

[Severity of obstructive sleep apnea syndrome relates to sleep architecture changes].

OBJECTIVE: To explore how obstructive sleep apnea syndrome (OSAS) affects sleep architecture and if OSAS severity and treatment relate to it. METHOD: A computer-assistant diagnostic system was used for polysomnography(PSG) recording. Respiratory events were scored automatically and corrected manually. Sleep was scored manually according to the standard set by Rechtschaffen. 31 controls and 147 OSAS patients(RDI > or = 5) were defined by PSG. 11 OSAS patients(RDI = 62.5 +/- 20.8) accepted nCPAP therapy. PSG were recorded both before and during nCPAP treatment. RESULT: (1) Compared with controls, OSAS group had increased sleep shift number (120 +/- 71 vs 92 +/- 60, P = 0.0106); (2) The number of slow wave sleep(SWS) (5 +/- 9 vs 8 +/- 8, P = 0.0035) and the ratio of total SWS time over total sleep time(TST) (5% +/- 8% vs 8% +/- 9%, P = 0.0062), were decreased and the rate of SWS deprivation(48% vs 26%, P < 0.05) were increased greatly in OSAS patients; (3) REM were less affected by OSAS than SWS because the ratio of its total time over TST, its onset number and deprivation rate had no significant difference between the two groups; (4) OSAS group had increased number of WASO (wake after sleep onset) (27 +/- 28 vs 19 +/- 18, P = 0.017) but the ratio of total WASO time over total sleep period had no significant difference between the two groups; (5) The ratio of total RWS(rapid wave sleep) time over TST (94 +/- 10 in OSAS group vs 91 +/- 12, P = 0.0136) and total RWS number(88 +/- 54 in OSAS group vs 65 +/- 45, P = 0.0075) were increased in OSAS group; (6) The above parameters were obviously disturbed in OSAS patients with RDI > or = 25 but had almost no change in patients with RDI < 25 compared with controls. (7) nCPAP could improve the above parameters but only number of WASO(no therapy: 34 +/- 20 vs therapy: 23 +/- 22, P = 0.011), shift number (no therapy: 151 +/- 62 vs therapy: 97 +/- 50, P = 0.019) and the ratio of total RWS time over TST (no therapy: 115 +/- 58 vs therapy: 69 +/- 34, P = 0.025) had statistical significance. CONCLUSION: OSAS severity relates to sleep architecture changes. Those had RDI < 25 had no change compared with control group. Sleep architecture changes could be improved by effective nCPAP therapy.

Adult↗

PubMed1998

[Effect of SNP on KCa of resistance vascular smooth muscle cell membrane in SHRsp].

OBJECTIVE: To investigate the effect of sodium nitroprusside (SNP) on calcium activated potassium channels (KCa) of mesenteric arterial A4-A5 branches resistence vascular smooth muscle cell membrane in Stroke-prone Spontaneously Hypertensive Rats (SHRsp) and its normotensive control WKY rats. METHODS: Cell-attached patch clamp technique was used. RESULTS: It was found that SNP could activate the KCa of the resistance vascular smooth muscle in both SHRsp and WKY. Under the same dose of SNP (1 nmol/L), the conductance and channel current amplitude etc. of the activated KCa in SHRsp were smaller than that in WKY rats. Given the same dose of 8-Br-cGMP (10 mumol/L), the cGMP activation of SHRsp KCa was less potentiated than that of WKY, appeared very similar to SNP/NO activation. CONCLUSIONS: The results suggested the KCa of hypertensive resistance vascular smooth muscle membrane appearing weaker response to relaxing factor EDRF/NO.

Animals↗

PubMed1998

[Analysis on quality control of drug susceptibility testing in the surveillance of drug resistance in tuberculosis in Henan].

OBJECTIVE: To evaluate the working quality of Henan province reference laboratory(PRL) in the surveillance of drug resistance (DRS) in Henan. METHOD: West Pacific Regional (WPR) Supranation Reference Laboratory(SRL) in South Korea conducted three times of quality control of drug susceptibility testing (DST) from SRL to PRL and to national reference laboratories(NRLs) in the region at the same time, and once of which from PRL to SRL. The exchanging strains of M. tuberculosis, which were clinical isolated ones containing both drug susceptible and drug resistant cultures, were tested for resistance to SM, INH, RFP and EMB. The DST procedure was proportion method, and L-J medium was used. RESULT: It was shown that the sensitivities for most of the four drugs in the three times of DST quality control from SRL to PRL were higher than their specificities, and that the sensitivities for both INH and RFP were 100%. And the accuracy, or agreement, for both INH and RFP was more than 90%, except for that of RFP in the first time. Compared with the results from SRL to NRLs (including Henan PRL), except for the specificity for SM in WPR being higher than that in Henan (84% versus 70%, P < 0.05), there was no significant difference between Henan and WPR on the specificity and sensitivity of the other drugs. Similar characteristics can be found in the results from PRL to SRL. And the efficiency for SM, INH and RFP was all higher than 90%. CONCLUSION: The quality control on Henan PRL meet the requirement of the WHO/IUATLD guidelines for surveillance of drug resistance in tuberculosis(1997).

Antitubercular Agents↗

PubMed1998

[Effects of simulated weightlessness and irradiation on metabolism of rat myocardial cells cultured in vitro].

To investigate the changes of the metabolism of rat myocardiac cells cultured in vitro under simulated weightlessness and gamma-irradiation, rat myocardiac cells were rotated on a horizontal clinostat, and irradiated with 2Gy 60Co gamma-ray. The results showed: (1) after irradiation, the LDH activity and SOD concentrations showed a significant increase, and the MDA concentration also increased. (2) After irradiation, LDH activity increased 60% on the 3rd day, and SOD concentration almost doubled on the first day. (2) MDA concentration also increased but it reduced to normal after the 3rd day. (3) Simple rotation on the clinostat showed no effect on the parameter, but there was a synergistic effect when it was combined with gamma-irradiation.

Animals↗

PubMed1998

Effects of simulated weightlessness and gamma-irradiation on myocardial cells and osteoblasts.

The effects of simulated weightlessness and gamma-irradiation on the structure and function of the myocardial cells and osteoblasts were investigated with a rotating clinostat and 2 Gy 60Co gamma-irradiation. The results showed: (1) Under the simulated weightlessness (SWL), the diameter of the myocardial cells decreased 40%. And the long-short diameter proportion decreased 70%, (P < 0.01); SWL affected the cell skeleton and the distribution of microfilament became ununiform, the orientation was unclear; SWL had significant effects on osteoblast disintegration and proliferation. The disintegration function decreased and the proliferation process was inhibited; (2) 2 Gy 60Co gamma-ray irradiation had significant effects on Lactate Dehydrogenase (LDH) activity and Superoxide Dismutase (SOD), Malonaldehyde (MDA) content in the myocardial cells, (P < 0.05) (5) A synergistic effect was observed between irradiation and SWL.

Animals↗

PubMed1998

[The powder X-ray diffraction analysis with Fourier spectrum of Chinese material medica Cortex Cinnamomi].

OBJECTIVE: To develop a method for the identification of Chinese medicinal materials in diffraction space. METHOD: Using powder X-ray diffraction analysis to obtain the Fourier spectrum of 10 samples of Cortex Cinnamomi. RESULTS: The analysis shows that each of the 10 samples has its own Fourier pattern topology and characteristic peaks which are connected with its chemical composition. CONCLUSION: Cortex Cinnamomi can be identified successfully according to its topology and characteristic peaks.

Cinnamomum↗

PubMed1998

[Cloning and sequencing of the VL and VH genes from the anti-vascular endothelial growth factor McAb hybridoma cell line].

OBJECTIVE: The light chain variable region (VL) and heavy chain variable region (VH) genes from the anti-VEGF165 McAb hybridoma cell line were cloned for construction of it's chimeric antibody. METHODS: The VL and VH genes were amplified from the total RNA of the VmD11 hybridoma with RT-PCR and cloned into vectors, and then analyzed by sequencing. RESULTS: The 320 bp VL gene belong to mouse kappa light chain subgroup V, the 354 bp VH gene belong to mouse heavy chains subgroup I (B). CONCLUSIONS: The nucleotide sequence analysis indicated that the cloned genes coded the light and heavy chain variable region of mouse respectively.

Amino Acid Sequence↗

PubMed1998

[A retrospective analysis of autogenous alveolar bone grafting in clefts of the lip and palate].

OBJECTIVE: To analyse factors which are able to influence the result of alveolar bone grafting (AABG). METHODS: A retrospective analysis was performed in a group of 54 alveolar cleft patients (30 males and 13 females, total 66 sides) who received AABG. The age range of the patients was 8-44 years. The cleft area was restored with autogenous cancerous bone from iliac crest. All the patients have been followed up for at least three months postoperatively. The result of the bone grafting was evaluated on the radoigraphs. RESULTS: 1. The overall survival rate of AABG was 94%, and clinical successful rate of AABG was 89%; 2. The successful rate of AABG was correlated with the age of the patients. The successful rate of AABG in group of patients above 18-year-old was significantly lower than other groups; 3. With the exception of cleft palate fistula operation, when the AABG was done simulatneously with other cleft lip and palate operations, the successful rate of AABG was not significantly different from that of the sole AABG operation; 4. The successful rate of AABG in patients with cleft lip or incomplete cleft palate was superior to patients with complete cleft palate. CONCLUSION: Forming of excelent bone grafting bed and closely surturing is the key to the success of AABG.

Adolescent↗

PubMed1998

[The study on the acoustic-phonetic features of marginal velopharyngeal closure].

OBJECTIVE: To study the acoustic-phonetic features of the cleft patients with marginal velopharyngeal closure. METHODS: The acoustic-phonetic features of 17 cleft patients with marginal velopharyngeal closure were analyzed with USSA sound spectrograph, contrasted by the features of 28 cleft patients with velopharyngeal incompetence and 18 patients with velopharyngeal competence. RESULTS: The manifestations of single vowel spectrum differ from that of the same vowel in sentence for MVPC patients. There are extra formants or strong nasal formants in a number of vowels spectrums in sentence, while they do not occur on single vowel spectrum. The spike and stop gap in the spectrograms of stops and affricatives may be absent or existing occasionally, and the noise energy in the lowest frequency area in the spectrograms of aspirated consonants may be watched or not. CONCLUSION: Acoustic analysis is very valuable to evaluate the state of marginal velopharyngeal closure. Analyzing the acoustic features of multiple vowels and consonants, and comparing the resonance characteristics of single vowel with the same vowel in continuous speech simultaneously are emphasized.

Acoustics↗

PubMed1998

[A study on the characteristics of articulation for functional speech problem after cleft palate surgery].

OBJECTIVE: To analyze the characterisctics of articulatory errors for the patients with speech problem and whose anatomic or physiologic defect such as velopharyngeal insufficiency were not indicated after cleft palate surgery. METHODS: Fifty patients with functional speech problem outlined above were tested using articulation test in chinese. The frequency of articulatory errors of all consonants was calculated. The interrelativity of the rate of affricates and plosives errors was analyzed. RESULTS: The frequency of affricates (j. z. ch. zh. et al) errors was higher than plosive's (b.d.g.k. et al). The difference of the rate of affricates and plosives errors was significant, statiscally (P < 0.001). CONCLUSION: It is suggested that the frequency of affricates errors was principal in this type of patients. They will be cured by speech training.

Adolescent↗

PubMed1998

[Retroperitoneal laparoscopic unroofing of renal cyst: use of close method].

OBJECTIVE: To study the close method of retroperitoneal laparoscopic unroofing of renal cyst. METHOD: A close method retroperitoneal laparoscopic unroofing of renal cyst was attempted in 35 cases between May 1995 and December 1996. The age of the patients ranged from 30 to 72 and the cyst size from 4.0 to 9.3 cm. RESULTS: The operative procedure took around 50 minutes. After a 1 - 18 month follow up, we observed the disappearance of all renal cysts. CONCLUSION: The laparoscopic procedure renders less trauma and discomfort to the patients and may be better indicated for symptomatic, simple renal cysts.

Adult↗

PubMed1998

[The enzymes activity of intestine grafts after combined small bowel/liver transplantation in rats].

OBJECTIVE: To study the alteration of the enzymes activity of intestine grafts after combined small bowel/liver transplantation in rats and the relations between their changes, functions and immune rejection. METHOD: A kind of model of combined small bowel/liver transplantation (SLT) was established in SD closed colony rats. The enzymes activity of grafts were examined at regular postoperative intervals with histochemical methods. RESULT: The enzymes activity of grafts disappeared eventually in isolated small bowel transplantation rats. Contrary, those in SLT rats were remained and recovered after operation. CONCLUSION: The rejection in grafted intestine can be prevented or delayed in SLT rats. The examination of activity of enzymes and nerves in grafts may be used to monitor rejection and study function of grafts.

Animals↗

PubMed1998

[Bilateral ureter within single nipple for cutaneous ureterostomy after radical cystectomy].

OBJECTIVE: To evaluate the effect of bilateral ureter within single nipple for cutaneous ureterostomy after radical cystectomy. METHOD: Bilateral ureter within single nipple for cutaneous ureterostomy was performed on 36 patients after radical cystectomy. RESULT: The nipple was formed well, and urinary drainage was patent. No death or severe complication occurred. The patients have been followed up for 3 months to 3.5 years. Urinary, electrolyte and renal functions were within normal levels. No pyelonephritis or hydronephrosis was observed in IVP, retrograde pyelography and/or sonographic examination of kidneys, no nipple constriction. A right ureter was pulled to the left retroperitoneum and formed a nipple with ureter left on the left abdominal wall. CONCLUSION: This is a simple and safe operation, especially suitable to the old and weak patients.

Adult↗

PubMed1998

[Functional changes of forelegs of rats after C6 and C8 nerve roots resection: experimental study].

OBJECTIVE: To find new nerve roots as dynamic source, we observed the effect of C(6) and C(8) resection on the function of forelegs of roots. METHOD: Considering the relationship between C(6) and biceps brachii muscle, C(8) and flexor digitorum profundus muscle, we resected C(6) and C(8) nerve roots of right side as the experimental side and compared with the left side. The position, pace, appearance of ulcer were observed on the foot and the phenomena of self-injury were seen regularly. The EMG and tensile strength of biceps brachii and flexor digitorum profundus muscles were measured immediately at two weeks and four weeks after operation. RESULT: The position of two sides of the rats was symmetrical. There were no limp, ulceration and phenomena of self-injury. Normal wave figure in EMG was noted in the experimental side. There was no significant difference in t test in EMG wave amplitude, maximum tetanized systole tensile strength and duration of isometric contraction. CONCLUSION: C(6) and C(8) nerve roots resection has no obvious influence on function of the leg.

Animals↗

PubMed1998

[Application of diode laser in the operation of retinal diseases].

OBJECTIVES: To evaluate the effects of diode laser photocoagulation applied on 43 cases of various kinds of fundus diseases with media opacity and on 40 cases during vitreo-retinal surgery. METHODS: Indirect ophthalmoscope laser photocoagulator was used for fundus diseases, and endolaser used during surgery. RESULTS: Vision was improved in 24.7% of the eyes, and was unchanged in 62.9% of the eyes. The neovascularization in proliferative diabetic retinopathy regressed in 78.3% of the eyes. All the retinal holes were closed. CONCLUSIONS: Diode laser can be used for treatment of some retinal diseases and in the operation. Good results can be obtained in the eyes with some extent of media opacity. No obvious side-effect was observed.

Adolescent↗

PubMed1998

[The purification and application of Epstein-Barr virus gp125].

Epstein-Barr virus (EBV) virion capsid antigen (VCA) gp125 as a diagnostic antigen was expressed in infected cells by recombinant vaccinia virus. The presence of IgA antibody to VCA of EBV was tested by ELISA in sera from nasopharyngeal carcinoma (NPC) patients and normal individuals. The ELISA consisted of three steps involving test serum, mouse monoclonal antibody to human IgA and rabbit anti-mouse IgG. The antibody titers of sera determined by this way correlated well with those by IF. The GMT by ELISA was 12 times higher than that by IF. Furthermore, efforts to develop gold-conjugated immunosorbent assay (GCISA), which is a more sensitive assay for measuring IgA antibody to VCA, has met with initial results.

Antibodies, Viral↗