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S Zhang

Publications and source records attributed to S Zhang.

At least 685 records · Page 38Linked to original sources
PubMed1998

[Study on electroneuromyography of 175 workers exposed to carbon disulfide].

A study on electroneuromyography of 175 workers exposed to carbon disulfide demonstrated that electroneuromyographic abnormalities of these workers were in accordance with characteristic alteration of axonal polyneuropathy. Electroneuromyography was an objective and sensitive method to detect the early damage of peripheral nerve caused by low-level exposure to carbon disulfide. The dose-response relationship between the exposure to carbon disulfide and the damage of peripheral nerve was demonstrated.

Adult↗
PubMed1998

[Risk of lung cancer among iron and steel workers in Anshan, China--case-control study].

A case-control interview study on 610 lung cancer patients and 959 controls was conducted among male workers in Anshan Iron-steel Complex. After adjusting for non-occupational risk factors, such as smoking, pulmonary disease, family history of cancer and the consumption of fruit, risks for lung cancer were significantly higher in workers engaged in smelting and rolling (OR = 1.5, 95% CI = 1.1-2.2), in the fire-resistant brick factory (OR = 2.9, 95% CI = 1.4-5.9), in general loading (OR = 2.5 95% CI = 1.0-6.1), and in coking (OR = 3.4, 95% CI = 1.4-8.5) for 15 or more years. Significant dose-response was observed for exposure to total dust and B[a]P, but not for specific chemical components of dust. The lung cancer risk increased 40% in iron and steel workers with long term occupational exposure.

Adult↗
PubMed1998

[Research on bending strength and fracture toughness of alumina-glass composite].

To develop a new ceramic material that can be machined and infiltrated with glass, a porous alumina blank sintered at 1350 degrees C was made of high purity, super fine alpha-alumina and then infiltrated with glass in this study. The density, bending strength and fracture toughness of the partially sintered alumina and alumina-glass composite were determined. The results indicated that the porous alumina density was 2.12 g/cm3, the three point bending strength 102 MPa, the fracture toughness 1.61 MPam1/2; that the alumina-glass composite density was 3.85 g/cm3, the three point bending strength 385 MPa, and the fracture toughness 4.05 MPam1/2. By SEM and EDXA analysis, lanthanum boroslicate glass was completely infiltrated into the 3 mm thick porous alumina blank for 6 h at 1150 degrees C. These suggest that the new developed alumina blank is suited for clinical use.

Aluminum Oxide↗
PubMed1998

[The effect of estrogen replacement therapy on plasma nitric oxide levels in postmenopausal women].

OBJECTIVE: To investigate the effect of estrogen replacement therapy (ERT) on plasma nitric oxide (NO) levels in postmenopausal women (PMW). METHODS: The plasma concentrations of NO and serum concentrations of estradiol (E2) were assessed before and 4 weeks after placebo or ERT administration in 10 cases of healthy PMW (control group), 17 cases of healthy PMW (healthy group) and 21 cases of PMW with hyperlipidemia (hyperlipidemia group) respectively. RESULTS: There was no difference in NO concentrations between before and after placebo administration in control group. In healthy and hyperlipidemia groups, the mean concentrations of NO were significantly higher 4 weeks after ERT administration than baseline. The positive correlation between the mean percent increase of NO and the E2 concentrations after ERT administration was statistically significant in healthy group. CONCLUSION: The increase of plasma NO concentrations caused by ERT may contribute to it cardiovascular protective effect in PMW.

Estradiol↗
PubMed1998

[Effects of orthodontic treatment on the shape of upper dental arch of patients after surgical operation of cleft lip and palate].

Occlusal casts were measured and analysed in the following groups: orthodontic group(9 subjects treated orthodonticly after surgical operation of the cleft lip and palate), untreated group (10 subjects untreated orthodonticly after surgical operation), normal group(10 young subjects with normal occlusion). The results were that the upper dental arch length and width increased evidently (P < 0.01) in the orthodontic group and almost returned to normal; in contrast, the upper dental arch length and width were inhibited in the untreated group; there were significant differences among the normal occlusion group, the orthodontic group, and untreated group (P < 0.01). The results suggest that during the period of growth and development, the shape of the upper dental arch of the patients can be evidently improved by the orthodontic treatment after the surgical operation of cleft lip and palate.

Adolescent↗
PubMed1998

[8-chloro-adenosine induced apoptosis in various human tumor cell lines].

OBJECTIVE: To study the effect of 8-Chloro-adenosine (8CA) on tumor cell growth and apoptosis. METHODS: Tumor and normal cell lines were treated with 8CA at different concentrations and cell growth was analysed by MTT assay. Cell apoptosis was evaluated by light microscopy, flow cytometry and chromosome DNA fragmentation. RESULTS: Treatment with 8CA at 10 mumol/L remarkably inhibited tumor cell growth. HL-60 promyelocytic leukemia cell line was more sensitive to 8CA than MGc-803 gastric mucoid adenocarcinoma cell line. NIH3T3 cells were relatively resistant to 8CA. The IC50 of HL-60 and MGc-803 cells was 1.2 mumol/L and 1.8 mumol/L, respectively, while that of NIH3T3 cells was 12 mumol/L. Further study showed that 8CA induced HL-60 and MGc-803 cell death characterized by apoptotic phenotypes, DNA content changes and chromosome DNA fragmentation. CONCLUSION: 8CA is a potential agent for tumor chemotherapy.

2-Chloroadenosine↗
PubMed1998

[Rejection of non-immunogenic tumor cells transfected with costimulatory molecule B7 after treatment with IFN-gamma in vitro].

OBJECTIVE: To explore immuno-gene-therapy of non-immunogenic tumor. METHODS: Non-immurogenic tumor cells B16 were transfected with B7-1 gene. The B7-1 gene transfected B16 cells (B7+ B16) were treated with recombinant murine interferon-gamma (rmIFN-gamma) in vitro, and then inoculated to C57BL/6 mice. RESULTS: While B7+ B16 cells grew progressively in syngeneic mice, tumorigenicty was significantly reduced when B7+ B16 cells were treated with rmIFN-gamma before inoculation to mice. Flow cytometric analysis of the rmIFN-gamma treated B7+ B16 cells showed significant up-regulation of MHC class I expression. CONCLUSION: For non-immunogenic tumor if the expressions of MHC class I molecules is low, providing co-stimulatory molecule B7 is not enough to reduce tumorigenicity. The B7-1 gene transfected B16 cells become non-tumorigenic or weakly tumorigenic when their MHC class I is up-regulated.

Animals↗
PubMed1998

[Three-dimensional reconstruction of electron beam computed tomography angiography for evaluating coronary artery bypass graft patency].

OBJECTIVE: To probe into the value of electron beam computed tomography (EBCT) for evaluating coronary artery bypass graft (CABG) patency follow-up. METHODS: EBCT enhanced single slice mode (SSM) and flow study were performed in 150 patients. The results of 3-D reconstruction of CABG were correlated with bypass operation records and coronary arteriograms in 7 patients. RESULTS: 318 of 399 coronary bypass grafts including IMA in 87/100(87%) and SVG in 228/296(77%) were patent. The overall patent rate was 79.7%. In 7 patients with 12 coronary bypass grafts, EBCT studies showed graft patency in 7 and occlusion in 5, as were confirmed by conventional graft angiography. CONCLUSION: EBCT angiography is a noninvasive method that could replace conventional coronary arteriography for CABG follow-up.

Adult↗
PubMed1998

[The effect of immunosuppression on the expression of perforin and granzyme B mRNA in hamster to rat liver transplantation].

OBJECTIVE: To explore the variation on the expression of perforin and granzyme B gene mRNA to judge the effect of immunosuppression in acute rejection of liver transplantation. METHODS: The expression of perforin and granzyme B gene mRNA was examined by RT-PCR in hamster to rat liver grafts under the immunosuppression of cyclosporine and splenectomy. Histological findings were studied comparatively. RESULTS: Cyclosporine and splenectomy could obviously suppress the rejection of liver grafts. The survival time of animals was significantly prolonged (37.1 days). The architecture of hepatic lobule was preserved. There was slight round cell infiltration in the portal tracts and no expression of mRNA of perforin and granzyme B genes could been seen in three weeks after transplantation. CONCLUSION: Perforin and granzyme B genes are of value in judging the effect of immunosuppression.

Animals↗
PubMed1998

[Hyperinsulinemia and insulin resistance in nondiabetic first-degree relatives of patients in familial NIDDM pedigrees].

OBJECTIVE: To study plasma insulin level and insulin sensitivity of nondiabetic first-degree relatives of patients in familial non-insulin-dependent diabetes mellitus (NIDDM) pedigrees. METHODS: Standard oral glucose tolerance test(OGTT) was conducted in 55 healthy controls and 97 first-degree relatives of NIDDM probands in familial NIDDM pedigrees. Plasma glucose and plasma insulin were determined at all phases after oral glucose load. Moreover, we calculated the glucose/insulin area ratio under the curve of OGTT (SGI) and the insulin sensitivity index (ISI) in all subjects to estimate their insulin sensitivity. RESULTS: In nondiabetic first-degree relatives, SGI and ISI were significantly decreased (P < 0.01), and plasma insulin was increased at 0, 30, 60, 120 minutes after administration of oral glucose load (P < 0.05 and P < 0.01), as compared with the controls, in matched age, body mass index (BMI) and proportion of sex. In both first-degree relatives and the insulin controls, SGI was positively correlated with ISI (r = 0.39, 0.41, respectively, P < 0.01) and both SGI and ISI were inversely correlated with BMI (r = -0.38, -0.39; -0.32, -0.25, respectively, P < 0.01). Moreover, FINS in the two groups was positively correlated with BMI (r = 0.30, 0.34, respectively, P < 0.05). CONCLUSION: In nondiabetic first-degree relatives of patients in familial NIDDM pedigrees, plasma insulin level was increased and insulin sensitivity was decreased as compared with the healthy controls. It suggests that they suffered from hyperinsulinemia and insulin resistance.

Adult↗
PubMed1998

Effect of gynostemma pentaphyllum mak on carcinomatous conversions of golden hamster cheek pouches induced by dimethylbenzanthracene: a histological study.

OBJECTIVE: To evaluate the effect of gynostemma pentaphyllum mak (GP) on carcinomatous conversions of leukoplasia of the golden hamster cheek pouch induced by dimethylbenzanthracene (DMBA). METHODS: 284 golden hamsters, ranging from 4 to 8 weeks of age, 80 to 100 grams in weight were randomly divided into three groups: control, model and experimental groups. Control group (8 hamsters) were sacrificed at week 0 and week 12 for control. Model group (123 hamsters) were pasted in bilateral cheek pouches with 0.5% DMBA, 3 times a week for establishment of experimental leukoplasia, and sacrificed at week 2 to week 9 (12-22 hamsters were sacrificed a week). Experimental group (153 hamsters) were divided into three subgroups. Subgroup A underwent simultaneous DMBA pasting and oral taking of GP, and were sacrificed at week 6 and week 9. Subgroup B underwent oral taking of GP for 12 weeks after completion of DMBA pasting. Subgroup C underwent DMBA pasting after completion of oral taking of GP for 12 weeks. RESULTS: The earliest epithelial dysplasia and carcinoma in situ occurred at week 3 and week 6 after DMBA pasting. There were significant differences between subgroup B and model group for 3 weeks' administration of DMBA (P < 0.05), and between subgroup C and model group (P < 0.01), while there was no difference between subgroup B and model group for 6 week's administration of DMBA (P > 0.05). CONCLUSIONS: GP could inhibit and reverse the carcinomatous conversions of leukoplasia of golden hamster cheek pouches, indicating its positive anticarcinogenic effect.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1998

[A study of p16 gene and its protein expression in rhabdomyosarcoma].

OBJECTIVE: To evaluate the relationship between alteration of p16 gene, its protein expression and the pathogenesis and development of rhabdomyosarcoma (RMS). METHODS: 44 cases of RMS were examined for alteration of p16 gene with PCR-SSCP and 47 cases of RMS were examined for p16 protein expression with immunohistochemical method. RESULTS: The homozygous deletion of p16 gene was observed in 2 cases and mutations in 6 cases. Of these 8 cases with altered p16 gene, 6 had extensive invasion, recurrence or metastasis. The total negative rate of p16 protein expression in RMS was 38.3% (18/47 cases). Of these 8 cases with alterations of p16 gene, negative expression for p16 protein was observed in 7 cases and positive in only 1 cases. In contrast, no structural abnormalities of the p16 gene were detected in another 11 cases with negative expression of p16 protein. Higher rates of p16 gene abnormality and loss of p16 protein were observed in ARMS than in ERMS. Higher rate of extensive invasion, recurrence or metastasis was also found in the group negative for p16 protein. CONCLUSION: The abnormalities of p16 gene and loss of p16 protein expression may be related to the pathogenesis and development of some RMS.

Cyclin-Dependent Kinase Inhibitor p16↗
PubMed1998

[p53 gene mutations in mouse skin tumors induced by DMBA-TPA-MNNG].

OBJECTIVE: To investigate the relationship between p53 gene mutations and mouse skin tumors induced by three-step carcinogenesis. METHODS: The exons 5-8 of p53 gene were examined in 37 DMBA-TPA-MNNG induced mouse skin tumors [including 6 mice with papillomas, 15 mice having well differentiated squamous cell carcinomas (SCCI) and 16 mice with intermediately differentiated squamous cell carcinomas (SCC II)]. RESULTS: No p53 gene mutation was detected in the papilloma group, whereas 25.8% (8/31) of the SCC group had p53 gene mutations (4/15 of the SCC I mice and 4/16 of the SCC II mice). A total of 9 mutations were found in 8 mice with SCC, of which 7 were located in exon 8 and 7 were G-->A transitions. CONCLUSION: The p53 gene mutations occurred during the process of malignant transformation from papilloma to SCC induced by three step carcinogenesis.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1998

Contribution of the absence of aspartic acid at position 57 of the HLA-DQ beta chain to predisposition to insulin-dependent diabetes mellitus in a southern Chinese population.

OBJECTIVE: To investigate the association of the absence or presence of aspartic acid at position 57 of the HLA-DQ beta chain (NA or A) with susceptibility or resistance to insulin-dependent diabetes mellitus (IDDM) in a Southern Chinese population. METHODS: Sixty-nine IDDM patients and 47 healthy controls in a Southern Chinese population were HLA-DQB1 genotyped by one-step sequence specific polymerase chain reaction (ssPCR). RESULTS: The frequencies of NA and A were 64.5% and 35.5% in the IDDM patients, and 40.4% and 59.6% in the control subjects respectively (RR for NA was 2.68, P < 0.01). The frequencies of NA/NA, NA/A and A/A phenotypes were 47.8%, 33.3% and 18.8% in the IDDM patients, and 31.9%, 17.0% and 51.1% in the controls respectively (P < 0.01). The frequency of A/A phenotype was significantly lower in the IDDM patients than in the control subjects (RR = 0.22, P < 0.01). DQB1* 0302 and DQB1* 0201 were more frequent in IDDM patients than in control subjects. The younger the age of IDDM onset, the higher the allele frequencies of DQB1* 0201 and DQB1* 0302. CONCLUSION: The present study suggests that the NA confers the susceptibility to IDDM, while the A confers the protection against IDDM in patients of Southern Chinese origin. These associations are more clearcut in childhood-onset IDDM patients.

Adolescent↗
PubMed1998

Three-dimensional reconstruction of electron beam computed tomography angiography for evaluating coronary artery bypass grafts.

OBJECTIVES: To probe into electron beam computed tomography (EBCT) angiography and 3-D reconstruction of coronary artery bypass grafts (CABG) and to evaluate the clinical application of EBCT angiography and 3-D reconstruction of CABG. METHODS: EBCT angiography with 3-D reconstruction was achieved in 150 patients (142 men and 8 women, mean age, 57 +/- 8 years) with 399 grafts including 100 internal mammary artery grafts (IMG), 296 saphenous vein grafts(SVG) and 3 radial artery grafts (RAG) respectively. The time from bypass surgery to EBCT scanning ranged from 7 days to 120 months, averaging 15 +/- 28 months. Enhanced single slice mode (SSM) and flow studies were performed in all patients. The results of 3-D reconstruction of CABG were compared with bypass operation records and with coronary arteriograms (7 patients). RESULTS: 150 patients underwent successfully EBCT angiography and CABG 3-D reconstruction. According to 3-D reconstruction of the coronary bypass grafts with flow studies, 318 of 399 coronary bypass grafts were patent including IMG patency in 87/100 (87%), SVG in 228/296 (77%) and RAG in 3/3 (100/100). The overall patent rate was 79.7%. In 7 patients with 12 coronary bypass grafts, EBCT studies showed graft patency (7 grafts) and occlusion (5), which were confirmed by conventional graft angiography. CONCLUSIONS: EBCT angiography with 3-D reconstruction is effective in providing the entire anatomic structure of coronary bypass grafts and evaluating coronary bypass graft patency. EBCT flow study can provide quantitative data for evaluating coronary bypass graft patency and for supplemental diagnosis of CABG 3-D reconstruction. EBCT angiography is a noninvasive technique that could replace conventional coronary arteriography for follow-up survey of coronary bypass surgery in future.

Adult↗
PubMed1998

[Protecting infection by using rhG-CSF in patients with lung cancer during chemotherapeutic courses].

OBJECTIVE: To recognize the prophylactic effect of rhG-CSF used on infection complications secondary to chemotherapy in patients with lung cancer. METHOD: The infection complications and the neutropenia secondary to chemotherapy in 163 cases of lung cancer patients with or without rhG-CSF were retrospectively analyzed. RESULT: Rhg-CSF administration reduced the frequency of infection complications, and there was a significant difference(P < 0.005) in the frequency of infection between the G-CSF group's patients (infections incidence 25%) and non-G-CSF group's (56%). The incidence of neutropenia in G-CSF group' patients is obviously less than that in non-G-CSF group's (P < 0.005). The median number of days of the neutropenia (neutrophil count of < 1.0 x 10(9) in G-CSF group(3 days) is less than that in non-G-CSF group(4 days)(P < 0.001). However, there was no significant difference (P > 0.05) between G-CSF group(63%) and non-G-CSF group(76%) in terms of response of the infection complications. CONCLUSION: Our data has shown that the administration of rhG-CSF as an adjunct to chemotherapy in patients with lung cancer can accelerate neutrophil recovery and shorten the duration of neutropenia, and lead to reductions in the incidence of infection complications, and also has the potential to increase the amount of cytotoxic chemotherapy and the quantity of life.

Adenocarcinoma↗