Biomedical subjects

L Wang

Publications and source records attributed to L Wang.

At least 1,315 records · Page 73Linked to original sources

PubMed1998

[Analysis of 25 episodes of acute occupational poisoning accidents and studies on its preventive strategy].

OBJECTIVE: To study the causes of the occurrence of severe acute occupational poisoning and its first-aid, and to improve its prevention and management. METHODS: Data of labor health conditions in 25 episodes of poisoning during the past 13 years were collected and analyzed statistically according to industries, enterprises and toxicals. RESULTS: Twenty-five episodes of poisoning accidents involved 131 persons, with 22 deaths. The incidence rate of occupational poisoning accidents in township and town enterprises exceeded that in state-owned ones. Ten kinds of toxicants were involved in the poisoning, with the hydrogen sulfide, benzene, carbon monoxide, phosgene and organophosphorus pesticide at the top five places in the number of cases with poisoning they caused. There were another 131 persons intoxicated during their emergency action and eight deaths, with a higher incidence and mortality rates due to poisoning than those in the operation workers. CONCLUSION: The major causes of the poisoning accidents were lack of knowledge of prevention and protection from them. It laid a good foundation for the establishment of emergency rescuing system in the grassroots.

Accidents, Occupational↗

PubMed1998

Inner ear damage in guinea pigs exposed to stable and impulse noise.

OBJECTIVE: To investigate the inner ear damage after exposure to stable noise, impulse noise and stable plus impulse noise in guinea pigs. METHODS: Ninety-six healthy guinea pigs were divided into 3 equal groups. (1) Stable noise group: exposed to 110 dBA stable noise for 3 days, 4 hours per day. (2) Impulse noise group: exposed to 165 dBA simulated cannon fire impulse noise 10 times successively at an interval of 10 seconds. (3) stable plus impulse noise group: exposed to the same stable noise as that in the first group, then after a 2-hour rest, the animals were followed with impulse noise exposures as that in the second group. After those exposure, each of the 3 groups was further divided into 4 subgroups according to the time after the noise exposure, namely, the right after, 7 d, 14 d and 30 d groups. The evoked cortical potential responses to click and tone burst stimulation sound were examined. The surface preparation and celloidine embedded serial section of the cochlea were observed under a light microscope. RESULTS: Both the stable and impulse noise could increase the hearing threshold and damage the inner ear hair cells. The damage in the first group was relatively slight, whereas in group 3 the damage was more severe than that in the other 2 groups. CONCLUSION: For seamen who are working in heavy noise environment, corresponding measures should be taken to protect their ears from noise which induces hearing loss.

Animals↗

PubMed1998

Research on nucleolar organizer regions of hippocampal neuron in Alzheimer's disease.

OBJECTIVE: To understand the cellular genetic expression of the cell's population by studying the nucleolar organizer regions (NORs) of hippocampal neuron of Alzheimer's disease (AD). METHODS: The postmortem human hippocampal tissues were divided into three groups, namely, the young, the elderly and the AD groups. Each group contained tissues from 10 patients. The study was conducted using image pattern analysis of the nucleoli-nucleoplasms ratio of the neurons of Nissl's stained pathological cerebral hippocampal tissues, the area of stain, and the integrating absorption of nucleoli of silver-stained NORs. RESULTS: The nucleoli-nucleoplasms ratio of the neurons of Nissl's stained cerebral hippocampal tissues, the area of stain, and the integrating absorption of the nucleoli of hippocampal neuron were decreased in the elderly and the AD groups as compared with the young group. However, the area of stain and the integrating absorption of the nucleoli of the hippocampal neurons were relatively increased in the AD group in comparison with the elderly group. CONCLUSION: Nissl's stain demonstrates the hypofunction of the hippocampal neurons in the elderly and the AD patients. The Silver stain of NORs shows the decline of rDNA transcription activity of the nucleoli of the hippocampal neurons in the elderly and the AD patients. However, the transcription activity of the nucleoli of the hippocampal neurons of AD patients was relatively improved, and the cellular genetic expression of the cell's population was relatively strengthened. These cellular morphological changes have probably reflected the cellular defensive system.

Adult↗

PubMed1998

[Therapeutic effects of ultrashort wave and He-Ne laser on experimental infection in skin flaps of rabbits].

In order to investigate the therapeutic effects of ultrashort wave and He-Ne laser on experimentally infected skin flaps, 24 lower abdominal skin flaps on 24 rabbits were established, under each flap 1 ml of S. aureus (9 x 10(8) bacterials/ml) was injected respectively. Then, ultrashort wave and He-Ne laser were utilized respectively in 2 groups once a day for 6 days, with on treatment in two another two groups as control groups. After the period of treatment, the 4 groups were evaluated in the bacterial amounts, thickness of skin flaps and degree of infection. The results showed that the skin flaps in the treatment groups were much better than those in the control groups. It suggested that both the ultrashort wave and He-Ne laser are helpful in the treatment of infection of S. aureus in skin flaps.

Animals↗

PubMed1998

[Effects of monocyte-derived endothelin on acute cerebral infarction].

To investigate the mechanism that monocytes participate in ischemic brain injury, endothelin (ET) levels in plasma, supernatants of cultured monocytes in vitro and those pretreated by dexamethason (DXM) were assayed by radioimmunoassay in 31 patients with acute cerebral infarction and 16 patients with hypertension (served as control). Compared with the control group, the ET levels in supernatants of cultured monocytes increased and positively related with those in plasma and degree of neurological damage in the acute cerebral infarction group, while the ET levels in supernatants of cultured monocytes pretreated by DXM decreased. This suggests that intensifying the synthesis and release ET may be one of the mechanisms for the involvement of monocytes in the pathologic process of ischemic brain injury during acute cerebral infarction. DXM can improve this process by inhibition of producing monocyte-derived ET.

Adult↗

PubMed1998

[Prevalence of premenstrual syndrome in reproductive women and its influential factors].

OBJECTIVE: To investigate the prevalence of premenstrual syndrome and its influential factors in reproductive women. METHOD: A questionnaire was used in 454 reproductive women aged 15-49 in Beijing. RESULTS: The prevalence of premenstrual syndrome in these women was 30.4%, among which 61.6% was mild, 34.1% moderate, and 4.3% severe. The order of frequency of the symptoms occurring in premenstrual syndrome was irritation, depression, anxiety, diarrhea, lack of concentration and hypersomnia. Women with higher cultural level, greater stress in life (work or study), dysmenorrhea, dislike menstruation and those with depression symptom had a higher incidence than those with lower cultural level, no stress in life, no dysmenorrhea, no dislike toward menstruation and no depression symptom (P < 0.05). CONCLUSIONS: Premenstrual syndrome is a common disease in reproductive women. Clinical doctors should pay attention and adopt comprehensive measures in order to reduce its incidence and improve the quality of life especially for women with high risk factors.

Adolescent↗

PubMed1998

[Relationship between the expression level of alpha-MHC gene and cardiac contractility during heart failure].

To investigate the molecular basis of the decrease in myocardial contractility during heart failure, an animan model of heart failure was set up by means of deoxycorticosterone-acetate impregnated silicone rubber implants in wistar rats. Cardiac contractility in normal and heart failure rats was examined, and gene expression of its myocardial contractile protein, alpha-MHC, was quantitatively analyzed at gene transcription level by using RNA slot blot hybridization. The results showed that the cardiac contractility and the alpha-MHC mRNA levels in heart failure rats were all lower than those in the normal. Statistical analysis showed a positive correlation between the cardiac contractility and the gene expression of alpha-MHC (r = 0.4143, n = 43, P < 0.05). The above results indicate that gene expression level of alpha-MHC is one of the key factors determining cardiac contractility.

Animals↗

PubMed1998

[An immunohistochemical study of the proliferating activity of ameloblastic fibroma and ameloblastic fibrosarcoma].

Six cases of ameloblastic fibroma (AF) and three cases of ameloblastic fibrosarcoma (AFS) were immunohistochemically investigated with a proliferating cell nuclear antigen (PCNA) monoclone antibody. Data on the PCNA labeling index (LI) of both epithelial and mesenchymal components were analyzed. The results showed that the PCNA LI of mesenchymal component of AFS (40.8%) was significantly higher than that of AF (3.2%) (P < 0.01) and that of the epithelial component of AFS (5.3%) was significantly lower than that of the mesenchymal one of AFS (P < 0.01). The results suggested that PCNA LI be a useful marker for the differentiation diagnosis of AF and AFS.

Cell Division↗

PubMed1998

[The changes of plasma calcitonin gene-related peptide level in women with normal pregnancy and pregnancy induced hypertension].

OBJECTIVE: To study the change of calcitonin gene-related peptide (CGRP) concentrations in maternal plasma of the normal pregnant women and patients with pregnancy induced hypertension (PIH) and relationship with CGRP and pathogenesis of PIH. METHODS: The plasma levels of CGRP in 59 cases of normal pregnant women (normal pregnancy group), 57 cases of PIH (PIH group), and 10 cases of nonpregnant women (control group) were determined with a sensitive radioimmunoassay. RESULTS: Plasma CGRP levels in normal pregnancy group increased with advance for the gestational week, reached the peak value (76.84 +/- 27.75 ng/L) in late trimester; plasma CGRP levels in PIH group decreased with series degree of PIH, levels of CGRP in moderate (49.76 +/- 23.11 ng/L) and severe PIH (46.35 +/- 22.32 ng/L) were significantly lower than that in mild PIH (71.28 +/- 21.98 ng/L) and the normal late pregnancy, the differences were significant (P < 0.005). There was no correlation between CGRP levels and the mean arterial pressure (MAP). CONCLUSIONS: The change of CGRP may play an important role in the pathogenic mechanism of PIH.

Adult↗

PubMed1998

[Study of magnesium and calcium levels of plasma and within erythrocyte before and after magnesium sulfate treatment in patients with pregnancy induced hypertension].

OBJECTIVE: To study the changes of calcium and magnesium levels in patients with pregnancy induced hypertension (PIH) and the therapeutic effect of magnesium sulfate (MgSO4). METHODS: The calcium and magnesium levels in plasma and erythrocytes of 36 patients with PIH and 14 healthy gravidi in their late pregnancy were determined and the changes after 4 hours infusion of MgSO4 as well. RESULT: Plasma calcium decreased significantly in moderate and severe PIH patients, but calcium increased and magnesium decreased in their erythrocytes. After MgSO4 infusion for PIH, magnesium levels in both plasma and erythrocytes increased, while calcium increased in plasma and decreased in erythrocyte to normal levels. CONCLUSION: Magnesium deficiency is the basis of calcium and magnesium disturbances in PIH, and MgSO4 treatment may improve the situation effectively.

Adolescent↗

PubMed1998

[Study of interleukin-6 and tumor necrosis factor-alpha levels in maternal serum and amniotic fluid in patients with preterm premature rupture of membrane].

OBJECTIVE: To study the change and clinical significance of maternal serum and amniotic fluid interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) levels in patients with chorioamnionitis and premature rupture of membrane (PROM). METHODS: Twenty normal term-pregnant women as control, and fourty-six women with PROM were enrolled for study. Maternal serum and amniotic fluid IL-6, TNF-alpha levels were measured by radioimmunoassay and enzyme-labeled immunosorbent assay (ELISA). Chorioamnionitis was diagnosed histologically. RESULTS: The maternal serum IL-6 levels and amniotic fluid IL-6, TNF-alpha levels were higher in PROM group than that of control (P < 0.01). There was significant positive correlation between maternal IL-6, amniotic fluid IL-6, TNF-alpha levels and the duration from rupture of membrane, (the longer was time, the higher were the maternal IL-6 and the amniotic fluid IL-6. TNF-alpha). There were 12 cases with chorioamnionitis in patients with PROM and their maternal and amnotic fluid IL-6, TNF-alpha levels were higher than that of non-chorioamnionitis (P < 0.01-0.05). CONCLUSION: IL-6 and TNF-alpha levels in maternal serum and amniotic fluid are valuable clinical indices for identification of chorioamnionitis in patients with PROM.

Adult↗

PubMed1998

[The relationship between epidermal growth factor and its receptor and fetal birth weight].

OBJECTIVE: To investigate the relationship of epidermal growth factor (EGF) and its receptor (EGFR) with fetal birth weight. METHODS: Using enzyme linked immunoabsorbent assay (ELISA) method the EGF concentrations of materal sera, cord blood sera and amniotic fluids were determined in 40 cases with IUGR, 40 cases with term normal birth weight, 25 cases with fetal macrosomias and 15 cases with normal non-pregnant women. Simultaneously using the immunohistochemical method EGFR in placentas and fetal membrance was determined in all groups of pregnancy. RESULTS: The EGF levels in normal non-pregnant women were lower than that in all groups of pregnancy. The EGF concentrations of materal sera, cord blood sera and amniotic fluid in IUGR group were lower than that in normal birth weight group. EGF levels were no difference between fetal macrosomias group and normal birth weight group. There is a positive correlation between the fetal birth weight and EGF concentrations in maternal sera, cord blood sera and amniotic fluids. In IUGR group the number of EGFR in placent and fetal membrane was less than that in normal birth weight group. In macrosomia group placental EGFR number was more than that in normal birth weight group. CONCLUSIONS: EGF and its receptor levels are related with IUGR, EGF concentrations in maternal sera and amniotic fluids in the third trimester may be a valuable index for assessing the fetal growth.

Adult↗

PubMed1998

[Association between ACE gene polymorphism and therapeutic responsiveness of ACEI in diabetic nephropathy].

OBJECTIVE: [corrected] To clarify the association between ACE gene polymorphism and therapeutic responsiveness of ACEI in diabetic nephropathy. METHOD: With the polymerase chain reaction technique, the angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism was studied in 31 NIDDM patients, 58 NIDDM patients with nephropathy, and 50 normal controls. RESULTS: There was no significant difference in the frequency of ACE genotypes among those NIDDM patients, NIDDM patients with nephropathy and nomal controls. Among 40 patients of DN group treated with ACE inhibitor(ACE-I), there was significant difference in genotype distribution between 19 efficacious cases and 21 nonefficacious cases: 8/2/9 vs 1/3/17 had DD/DI/II genotypes responsively (P < 0.01), DD genotype was best and II genotype was worst in therapeutic efficacy of ACE-I in NIDDM patients with nephropathy. CONCLUSION: The examination of ACE gene polymorphism is helpful for the diagnosis of the therapeutic efficacy of ACE-I in NIDDM with nephropathy.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1998

[Proliferative effect of low energy laser and colony stimulating factor on human umbilical cord blood hematopoietic cells].

OBJECTIVE: To study the proliferative effect of low energy laser on human cord blood hematopoietic cells in vitro and the relationship between the effect of low energy laser and colony stimulating factor (CSF). METHODS: Human umbilical cord blood hematopoietic cells were irradiated with copper vapour laser and cultured in vitro. The number of colony and cells was calculated. RESULTS: Laser irradiation synergized with CSF in expansion of cord blood hematopoietic cell. The GM-CFUc number from the group treated with irradiation plus CSF increased significantly as compared with that from other groups including laser irradiation or CSF treatment alone or control (P < 0.01). Reincubation of cord blood cells in the soft agar medium revealed that secondary colonies were formed and the absolute number of colony was obviously increased as compared with that before liquid culture. The number of colony in irradiation group was more than these of non-irradiation group. CONCLUSION: Low energy laser irradiation for cord blood stem cells is effective in vitro expansion of cord blood stem cells.

Cell Division↗

PubMed1998

[Changes of plasma nitric oxide and endothelin levels in normal pregnant women and pregnancy induced hypertension].

OBJECTIVE: To investigate the relationship of nitric oxide (NO), endothelin-1 (ET-1) levels and pregnancy induced hypertension (PIH). METHODS: 60 patients with PIH, 45 normal pregnant women and 15 normal non-pregnant women were studied. Plasma NO levels were determined. The stable metabolic product NO2-/NO3- of NO was letermined by Griess reaction. Plasms ET-1 levels were measured with radioimmunoassay. RESULTS: The NO2-/NO3- levels of the normal pregnancy group were significantly higher than those of the control group (P < 0.01), particularly in the second trimester of pregnancy. The NO2-/NO3- level of PIH was significantly lower in maternal plasma than that of the last trimester of normal pregnancy (P < 0.01) and nonpregnancy (P < 0.05), and it decreased with the disease development. In severe PIH the umbilical venous blood NO2-/NO3- level was significantly lower than that in the normal term pregnancy group (P < 0.01). The maternal plasma ET-1 level in PIH was significantly higher than that in the normal term pregnancy and control groups (P < 0.01). CONCLUSION: PIH might be related to decreasing synthesis and release of NO, and increasing ET-1 production.

Adult↗

PubMed1998

[Detecting cytokines in patients with preterm premature rupture of membrane].

OBJECTIVE: To study the relationship of maternal blood and amniotic fluid cytokine levels in patients with preterm premature rupture of membrane and chorioamnionitis. METHODS: IL8 and TNF alpha levels of maternal blood and amniotic fluid were determined by 125I radioimmunoassay (RIA) and an enzyme-labeled immunosorbent assay (ELISA). Chorioamnionitis was diagnosed by fetal membrane histology. RESULTS: The maternal serum IL8 levels and amniotic fluid IL8, TNF alpha levels were higher than those of controls (P < 0.05). There was significant relationship between maternal serum and amniotic fluid IL8, TNF alpha with the time of the premature rupture of membanes. The longer the time the higher the maternal serum IL8 and amniotic fluid IL8, TNF alpha; There were 13 patients with chorioamnionitis, and their maternal serum and amniotic fluid IL8, TNF alpha were higher than those of patients with non-chorioamnionitis (P < 0.01-0.05). CONCLUSION: IL8, TNF alpha levels of maternal serum and amniotic fluid are valuable clinical indexes in identification of chorioamnionitis in patients with preterm premature rupture of membranes.

Adult↗

PubMed1998

[Antisense N-ras1 gene inhibits the proliferation of VSMC induced by bFGF after arterial injury].

OBJECTIVE: To develop a new way to prevent the process of restenosis after arterial injury, we transfer the recombinant antisense N-ras1 gene to the cultured SMCs and studied the influence of gene therapy with antisense N-ras1 on the SMCs proliferation induced by bFGF. METHODS: With the recombinant antisense N-ras1 plasmids (fpGv1-MT-N-ras1) transfered to the cultured SMC, we studied the effect on the SMCs proliferation induced by bFGF. RESULTS: The results of the experiment indicated that the count of cells transfered antisense N-ras1 was 16.8 +/- 1.3 x 10(4), the control cells transfered fpGv1-MT retrovirus vector were 30.1 +/- 1.2 x 10(4) (cell/ml) (P < 0.001). cell [3H] thymedine incorporation was 7,643 +/- 672 cpm in gene therapy cells, and 15,131 +/- 138 cpm in vector control cells (P < 0.001). Gene therapy cells ras mRNA and p21 were significantly decreased by Northern blotting and Western blotting technique. CONCLUSION: These results suggest that antisense N-ras1 gene may inhibit the proliferation of cultured VSMC induced by bFGF.

Animals↗

PubMed1998

Response of HIV/AIDS Patients to Hepatitis B Recombinant Vaccine.

Studies have demonstrated that HIV infection negatively affects the immune response to hepatitis B vaccine. The present study evaluated the seroconversion to the recombinant vaccine against hepatitis B applied in HIV patients. Twenty-two patients were included in the study group all with confirmed HIV infection and with negative serum markers to hepatitis B. The control group was composed of 18 healthy individuals with negative markers for hepatitis B. All subjects were vaccinated with 20µg of ENGERIX B((R)) at 0, 1 and 6 months (3 doses). The antibody response was quantitatively assessed 1 month after the third dose of recombinant vaccine. CD4 T lymphocyte counts were also performed in those beginning vaccination. Of 22 patients in the study group, only 10 (45.5%) responded to vaccination with protective levels (over 10mIU/ml). In the control group, all of the subjects responded (p=0.005). Seventeen patients in the study group had their CD4 lymphocytes measured. The results suggested a direct relationship between the level of CD4 lymphocyte counts and response to the vaccine. The rate of response to hepatitis B recombinant vaccine with 3 doses of 20µg of HBsAg in patients infected by the human immunodeficiency virus was significantly lower than in the control group. Patients with low CD4 T lymphocyte counts are likely to have an inadequate response to the current method of hepatitis B vaccination.

Journal Article↗