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Yan-hong Zhou

Publications and source records attributed to Yan-hong Zhou.

7 recordsLinked to original sources

Current rectification by asymmetric molecules: an ab initio study.

Current rectification effect in an asymmetric molecule HCOO-C6H4-(CH2)n sandwiched between two aluminum electrodes has been studied using an ab initio nonequilibrium Green's function method. The conductance of the system decreases exponentially with the increasing number n of CH2. The phenomenon of current rectification is observed such that a very small current appears at negative bias and a sharp negative differential resistance at a critical positive bias when n>or=2. The rectification effect arises from the asymmetric structure of the molecule and the molecule-electrode couplings. A significant rectification ratio of approximately 38 can be achieved when n=5.

Journal Article↗

[The effects of burn serum on the erythropoiesis and granulopoiesis in bone marrow in mice].

OBJECTIVE: To observe the effects of burn serum on the erythropoiesis and granulopoiesis in bone marrow in mice, and to explore the possible underlying mechanism. METHODS: Murine bone marrow cell (BMC) strain was prepared routinely and was employed in the establishment of the culture system of colony forming units of erythrocytes, or granulocytes and monocytes. To both sets of culture system normal murine serum (N group) and burn serum, which was collected from the mice with 15% full thickness burn at 12 postburn hours (PBH) and 1, 3, 5, 7 and 10 postburn days (PBD), (burn serum group) was added. In addition, positive control and blank control groups were set accordingly. The stimulating activity of all kinds of sera on the BMCs in the two sets of culture system was determined. The changes in the burn serum concentrations of EPO and GM-CSF were detected by radioimmunoassay, and the data were analyzed by logarithmic linear fitting correlation with the former influence of burn sera on the erythrocytes and granulocytes. RESULTS: (1) Burn sera exhibited obvious stimulation promoting activity on the erythropoiesis and granulopoiesis in BMC, and the activity peaked (384 +/- 60 and 127 +/- 16 CFU) on 1 PBD and decreased thereafter to approach the values found in normal sera group (125 +/- 14 and 34 +/- 20 CFU) on 7 PBD. (2) The EPO content in burn serum was evidently higher than the normal value (P < 0.01) during 12 PBH to 7PBD period. The GM-CSF concentration was obviously higher than the normal value (P < 0.05) at 12 PBH and on 1 PBD. (3) The EPO concentration in burn serum was significantly and logarithmically correlated with the stimulation promoting activity of burn serum on erythropoiesis (r = 0.8570, P = 0.0137). But the GM-CSF concentration in culture with burn serum was not correlated with the stimulation promoting activity of burn serum on granulopoiesis (r = 0.7049, P > 0.05). CONCLUSION: The sera harvested from burned mice during early postburn stage exhibited strong stimulation promoting activity on the erythropoiesis and granulopoiesis in bone marrow. The increased EPO level in burn serum might be the important factor contributing strong stimulation action on erythropoiesis, while increased GM-CSF level was not.

Animals↗

[Expression and location of UBAP1 protein associated with nasopharyngeal carcinoma].

OBJECTIVE: To analyze the expression and location of coding protein of UBAP1 gene and to understand the relationship between the expression pattern of the protein and cell carcinogenesis. METHODS: Bioinformatics was used to analyze the protein character to provide an available clue of subsequent research. The codon frame cDNA was amplified by PCR, and subcloned into enhance green fluorescence protein (EGFP) of pEGFP-C2. The recombinant plasmid was transfected into HNE1 cells. The expression of coding protein was observed by fluorescence microscopy. RESULTS: The expressed GFP-fusion protein generated striking green fluorescence in the cytoplasm in HNE1 cells. EGFP/UBAP1 was expressed and existed mainly in the nuclear, especially accumulated on the nuclear envelope. CONCLUSION: The expression difference in HNE1 might be related to the carcinogenesis of NPC.

Base Sequence↗

[Surveillance of incidence of cerebral hemorrhage in community populations in Changsha].

OBJECTIVE: To observe the incidence of cerebral apoplexy among the community populations in Changsha, Hunan Province. METHODS: Surveillance of the incidence of cerebral apoplexy and analysis of its subtypes were conducted among 10,000 urban residents in Changsha selected by random cluster sampling from 1986 to 1990. The number of people under surveillance was amplified to 50,000 in 1991 and the studies lasted to December 2000. RESULTS: Among the Chamgsha populations, the annual average incidence of cerebral hemorrhage was 171.7 per 100,000 during the period 1986 - 1990. The annual average incidence of cerebral apoplexy was 238.9/100,000 with an adjusted rate of 200.2/100,000, and the annual average incidence of cerebral hemorrhage, accounting for 53.8% of cerebral apoplexy, was 128.5/100,000 with an adjusted rate of 100.3/100,000). CONCLUSION: The annual average incidence of cerebral hemorrhage in community populations is 128.5 per 100,000 during the period of fifteen years, 1986 - 2000, in Changsha, one of the areas with high incidence of cerebral hemorrhage.

Cerebral Hemorrhage↗

[Evaluation on a cohort based population intervention project regarding risk factors for cerebrovascular diseases].

OBJECTIVE: To analyze the changes of risk factors in cerebrovascular diseases in cohort-based population after intervention and evaluating the intervention effect. METHODS: In 1987, an intervention cohort and a control cohort were selected randomly in urban areas of Changsha. Risk factors in cerebrovascular diseases were investigated in two cohort populations aged over 35 years as baseline indication. Then comprehensive prevention of cerebrovascular diseases was carried out in intervention cohort during 1987 - 2000. After intervention for 14 years, a reexamination was taken in the two groups noted above. RESULTS: After 14 years, the prevalence of diabetes mellitus, hypertension, mean systolic and diastolic pressure, weight increased from 33.8% to 35.7%, 30 to 129 per 10,000, 128.41 mm Hg to 134.49 mm Hg, 77.78 mm Hg to 78.54 mm Hg, 54.80 kg to 57.78 kg in the intervention group, respectively while the baseline indication increased from 35.9% to 56.8%, 30 to 228 per 10,000, 127.70 mm Hg to 141.80 mm Hg, 78.27 mm Hg to 82.89 mm Hg, 54.92 kg to 59.69 kg in the control one. The changes were of statistical significance in each group except diastolic pressure and the prevalence of hypertension in intervention group, but all the parameters increased significantly in the control group; rate of alcohol intake decreased significantly in two groups, but rate of cigarette smoking decreased with no significance. The changes between two groups were not significant either; the cumulative incidence of stroke was significantly lower in intervention cohort (3.4%) than in control cohort (4.7%). CONCLUSION: The risk factors for cerebrovascular diseases (such as hypertension, diabetes mellitus etc.) were increasing along with by aging. Intervention programs can delay the increase of risk factors and down-regulate the incidence of stroke.

Alcohol Drinking↗

[Evaluation of effectiveness of intervention on risk factors for cerebrovascular disease in three cities of China].

OBJECTIVE: To evaluate the effects of community intervention on risk factors of cerebrovascular disease. METHODS: With cluster sampling, 2,586 and 2,723 women and men aged 35 to 74 were selected randomly as intervention cohort and control cohort, respectively, from about 300 thousand community population in Beijing, Shanghai and Changsha, during 1997 to 2000. Their blood pressure, levels of blood lipid, body mass index (BMI) were measured and status of smoking and alcohol consumption were surveyed as indices of evaluation. Health education for smoking quit, alcohol consumption restriction and reinforced treatment for diabetic and hypertensive patients were implemented in the intervention communities. And, 2,544 and 2,533 persons in the two cohorts responded three years after intervention, and then all the indices mentioned above were measure again for them. RESULTS: Average reduction in systolic blood pressure by 3.21 mm Hg and serum level of total cholesterol by 0.58 mmol/L was achieved in intervention cohort after intervention, but with 0.48 mmol/L increase in triglyceride. Average blood levels of both high density lipoprotein-cholesterol (HDL-C) and glucose increased in the two cohorts after intervention, but with 0.30 mmol/L net increase of blood glucose in control cohort. There was no significant difference in average increase of HDL-C between the two cohorts. BMI increased by 0.56 in control cohort, and no significant change in intervention cohort. Proportion of smoking decreased by 5.4% in men and 2.4% in women of intervention cohort, and no change in control cohort. CONCLUSION: Level of risk factors for cerebrovascular disease reduced significantly with community intervention.

Adult↗