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Biomedical subjects

Y Hu

Publications and source records attributed to Y Hu.

At least 127 records · Page 7Linked to original sources
PubMed2001

[Study on preparation and properties of moisture permeable polyurethane membrane used for dressings].

A new hydrophilic polyurethane(PU) performed-polymer has been developed with polyethylene glycol(PEG) instead of general polyether. The solution of performed-polymer is poured casting a permeable membrane used for the outer layer of the bilayer dressings. The effects of molecular weigh (Mn) of PEG, the usage of cross-link agents, solvents and water in the solution on the moisture permeation of PU membrane have been studied. It has been shown that the membrane prepared is a porous moisture permeable membrane. The optimum conditions of preparing membrane are: Mn of PEG is 2,000-4,000, the mixture of acetone and N,N-dimethylformamide (DMF) is used as solvents, and the temperature of performance membrane is 50 degrees C-80 degrees C. The moisture permeability of the PU membrane is 49-60 g/m2.h at 35 degrees C, which can meet the requirement of the wound dressings. In addition, the mechanism of the moisture permeation of PU membrane has been discussed.

Bandages↗
PubMed2001

[Dominant selecting culture medium of Peucedanum decursivum by orthogonal design].

OBJECTIVE: To select the optimum medium for callus culture of Peucedanum decursivum. METHOD: Orthogonal design was applied in determination of hormonal kinds and concentration, and qualitative analysis of callus was done initially. RESULTS: The MS basic medium with 1 mg/L 2,4-D was the best one; coumarin was detected in callus preliminarily. CONCLUSION: It was effective that orthogonal design applied in screening medium; feasible foundation was offered for Peucedanum decursivum cell culture producing active ingredient.

Apiaceae↗
PubMed2001

[The effects of ZMS on learning and memory ability and brain choline acetyltransferase in scopolamine-induced mouse model].

OBJECTIVE: To observe the effects of ZMS on learning and memory ability and on brain choline acetyltransferase activity. METHODS: A single intraperitoneal injection of scopolamine was used to establish a dementia mouse model. The learning and memory ability was detected by step-through and sted-down tests. And the choline acetyltransferase activity in brain was determined by 3H-acetyl-CoA incorporation analysis. RESULTS: ZMS could significantly reduce wrongness frequences, prolong incubation period of scopolamine-induced dementia mice in step-through and step-down tests (P < 0.01). ZMS could also significantly improve the activity of brain choline acetyltransferase (ChAT) (P < 0.01). CONCLUSION: ZMS could improve the learning and memory ability and the activity of brain ChAT in scopolamine-induced dementia mice. However, ZMS had no significant dose-response effect on improving the activity of brain ChAT, and the effect of Tacrine was similar to that of ZMS, it seemed unlikely that ZMS had a direct action on the ChAT. More probably, ZMS exerted its effect on ChAT activity and on learning and memory ability via elevating brain M receptor density.

Animals↗
PubMed2001

[Intervention of Fuzhenghuayu decoction on autocrine activation of hepatic stellate cells].

OBJECTIVE: To investigate the intervention of Fuzhenghuayu decoction on autocrine activation of hepatic stellate cell. METHODS: The drug serum containing Fuzhenghuayu decoction was collected from the normal rats, and cultured with activated hepatic stellate cells (HSC) in vitro. The conditional medium from the drug serum treated HSC was collected, and added to primarily cultured quiescent HSC. The primary cell proliferation was assayed by MTT colorometric test, and the contents of type I collagen and vasular endothelial growth factor (VEGF) in the medium were assayed with ELISA. RESULTS: The coditional medium from activated HSC could stimulate the proliferation and type I collagen secretion in the quiescent HSC. The drug serum inhibited this stimulating action and VEGF secretion from activated HSC. CONCLUSIONS: Fuzhenghuayu decoction has inhibitory action on the autocrine-activating pathway of HSC. The mechanism may be associated with inhibiting the secretion of VEGF by activated HSC.

Animals↗
PubMed2001

[Prevention and treatment of recurrent urinary system infection with estrogen cream in postmenopausal women].

OBJECTIVE: To evaluate the effect and feasibility of using estrogen cream for the prevention and treatment of recurrent urinary tract infection (UTI) in postmenopausal women. METHODS: Forty-five postmenopausal women with a history of recurrent UTI were divided into two groups (group premarin and group antibiotic). Participants were assigned to apply intravaginal premarin cream (group premarin, n = 30) or oral antibiotic (group antibiotic, n = 15) for 3 months respectively. Urine routine test, midstream urine and vaginal cultures, vaginal health score (VHS), vaginal cell maturation value (MV), endometrial thickness and blood estrogen level were obtained before and after the study. RESULTS: The incidence of UTI in the group premarin was significantly reduced as compared with that in the group antibiotic (2/27 vs. 12/15, P < 0.001). In the group premarin Lactobacilli reappeared (from 0 to 59.3%) and MV (from 9.2 +/- 6.8 to 74.6 +/- 14.1) and VHS (from 5.2 +/- 0.4 to 13.4 +/- 2.5) were improved after 3 months. There was no significant change in the group antibiotic. CONCLUSION: It seems that intravaginal use of estrogen cream would effectively prevent and reduce the UTI in postmenopausal women.

Aged↗
PubMed2001

Human stem cell model to study signal transduction and molecular regulation mechanisms in CML.

OBJECTIVE: To develop a primary human hematopoietic stem/progenitor cell model for chronic myeloid leukemia (CML) and study signal transduction and molecular regulation mechanisms in CML. METHODS: We developed a human model of p210BCR/ABL positive CML by transducing normal human umbilical cord blood CD34+ cells with a retroviral vector containing the b3a2 bcr/abl cDNA. We also examined whether this model recreated the cellular phenotype of CML by assessing cell adhesion, cell migration, cell proliferation and cell survival. RESULTS: We found that significantly more myeloid colony forming units grew from p210BCR/ABL expressing cells, adhesion of p210BCR/ABL expressing CD34+ cells to fibronectin was decreased but migration over fibronectin was enhanced compared with mock transduced CD34+ cells. In this model, we showed that the presence of p210BCR/ABL leads to elevated levels of p27kip in p210BCR/ABL expressing CD34+ cells. We also showed that multidrug resistance-1 (MDR-1) Pgp was upregulated in the p210BCR/ABL expressing cells which correlates with the expression of p210BCR/ABL. CONCLUSION: This primary human CML model recreates most of the features of CML and provides a useful tool to study signal transduction and downstream molecular regulation drived by the p210BCR/ABL oncogene in normal CD34+ cells.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Diagnosis and treatment of bronchial rupture from blunt thoracic trauma.

OBJECTIVE: To evaluate the diagnosis and management of bronchial rutpture from blunt thoracic trauma. METHODS: A group of 31 patients with bronchial rupture was involved. Chest roentgenography, tomography and bronchoscopy were performed on all patients. The surgical technique and complications were described. RESULTS: Diagnosis was confirmed by tomography and bronchoscopy in all the patients. End to end anastomosis was used in 26 patients. Four patients were operated with total pneumonectomy. One patient was repaired with an intercostal muscle and rib flap with blood supply. Of the 31 patients, one died of adult respiratory distress syndrome after operation. Most patients had excellent surgical outcomes. 81% (25/31) of the bronchial rupture were delayed in diagnosis and treatment. The classic symptoms and signs of bronchial rupture included subcutaneous emphysema, dyspnea and an intermediate coma interval. The roentgenogram showed mediastinal emphysema, pneumothorax, "drop lung" sign and marked radiodensity of hilum widened mediastinum. CONCLUSION: Bronchoscopy is a useful and accurate method to diagnose and treat the bronchial rupture, with which surgeons can easily locate the rupture site during surgery. Surgical treatment could restore pulmonary function in most patients.

Adolescent↗
PubMed2001

The regulatory action of Radix Astragali on M-cholinergic receptor of the brain of senile rats.

The changes in density of M-cholinergic receptors in different areas of senile rats and the regulatory action of Huang Qi ([symbol: see text] Radix Astragali, a drug for warming yang and replenishing qi) were observed by autoradiography. The results showed that the gray scale displayed in brain sections was clear and mainly distributed in the cortex, hippocampus and striate body, while that due to nonspecific combination was negligible. The gray scale in the cortex, hippocampus and striate body of the experimental group was markedly lower than that in the young control rats, decreased respectively by 24.87%, 14.12% and 12.76% (all P < 0.05); but it was obviously higher than those in the senile control rats, increased respectively by 24.15%, 14.38% and 13.47% (P < 0.05). The data indicate that Huang Qi ([symbol: see text]Radix Astragali) may up-regulate the decreased density of M-cholinergic receptors in the brain of senile rats.

Aging↗
PubMed2001

[Development of biogenic VOC emissions inventory with high temporal and spatial resolution].

A new method was developed to estimate biogenic VOC emissions with high temporal and spatial resolution by use of Mesoscale Meteorology Modeling System Version5 (MM5). In this method, the isoprene and monoterpene standard emission factors for some types of tree in China were given and the standard VOC emission factors and seasonally average densities of leaf biomass for all types of vegetation were determined. A biogenic VOC emissions inventory in South China was established which could meet the requirement of regional air quality modeling. Total biogenic VOC emissions in a typical summer day were estimated to be 1.12 x 10(4) metric tons in an area of 729 km x 729 km of South China. The results showed the temporal and spatial distributions of biogenic VOC emission rates in this area. The results also showed that the geographical distribution of biogenic VOC emission rates depended on vegetation types and their distributions and the diurnal variation mainly depended on the solar radiation and temperature. The uncertainties of estimating biogenic VOC emissions were also discussed.

Atmosphere↗
PubMed2001

[Effects of grazing and cultivating on emission of nitrous oxide, carbon dioxide and uptake of methane from grasslands].

Measurement of N2O, CO2 and CH4 with the optimized closed chamber/GC technique in the typical grassland, which were influenced by human activities, grazing and cultivating first time in situ were carried out in Inner Mongolia of P. R. China from 1998 to 1999. It was found that wheat cropping can increase N2O production 3 times than the native, and changed a CO2 sink of Inner Mongolia Steppe to a significant source, increased efflux CO2(C) average 14.3 mg.(m2.h)-1 from Jun. to Dec. in 1998. CH4 uptake was highly increased if there was grazing lightly. There were no effects of wheat cropping on CH4 uptake and no significant results of grazing on N2O emission. Soil moisture and temperature were the key factors, other than human activities, which affect the patterns of seasonal variation of N2O and CO2 emission and CH4 uptake. Highly inter-annual variations, which resulted from the annual precipitation, of the exchange fluxes and seasonal variation patterns of N2O and CO2 emission and CH4 uptake there were. It was a fact that N2O and CO2 emission from the soils was inversely related to CH4 uptake.

Animal Husbandry↗
PubMed2001

Inhibition of glutamate carboxypeptidase II by phosphonamidothionate derivatives of glutamic acid.

A limited series of N-thiophosphonyl-glutamates were found to be inhibitors of the prostate-specific membrane antigen (PSMA) form of glutamate carboxypeptidase II. Comparative inhibitory profiles of an analogous O-thiophosphonyl-2-hydroxyglutarate revealed that the amido-linkage of the N-thiophosphonyl-glutamate provides a significant enhancement of inhibitory potency presumably due to significant hydrogen-bonding interactions with acceptor groups in the active-site of PSMA resulting in tighter binding. An analogous N-phosphonyl-glutamate exhibited significantly greater inhibitory potency than the parent N-thiophosphonyl-glutamate indicating that the sulfur ligand of the N-thiophosphonyl-glutamates is responsible for less favorable active-site interactions than oxygen, potentially due to steric crowding from the longer P-S bond or as a result of active-site metal substitution of Co(II) for Zn(II) arising from assay conditions.

Antigens, Surface↗
PubMed2001

[Evaluation of the effects of two operative option in the treatment of orbital fractures].

OBJECTIVE: In order to explore the treatment and it's clinical effects of orbital fractures. METHOD: 34 patients were separately treated with nasal endoscopic surgery and external nose incision surgery. RESULT: The total effective rate of nasal endoscopic surgery and external nose incision surgery was 90.0%, 91.6% respectively. There was no significant difference between the two groups (P > 0.05). CONCLUSION: Treating orbital fractures under nasal endoscopic surgery has advantages such as no incision on face, less damage, clear view and easy recheck after operation. It is the best way to treat this kind of disease.

Adolescent↗
PubMed2001

[Audiological findings of the aging across the urban and rural of Suzhou].

OBJECTIVE: To determine the epidemiological characteristics of old people's hearing. METHOD: Questionnaires, physical examination, audiometry and bio-chemical tests were performed on the elders above 60 years old in part of the urban and rural area of Suzhou with random sample survey. RESULT: A total of 1,040 individuals was investigated, among which 505 were from urban, and 535 were from rural. 33 of 505 senior citizen (6.53%) were nososacusis, 282 (55.84%) were presbycusis and 21 (4.16%) were noise-induced deafness; In the rural area, 35 of 535 (6.54%) were nososacusis, 232 (43.36%) were presbycusis, and 4 (0.75%) were noise deafness. There was significant difference of the incidence of presbycusis between urban and rural. The audiometric thresholds chart manifested that the threshold elevated with age increasing especially in high-frequency. CONCLUSION: The etiology of hearing loss of elders was mainly due to presbycusis. The higher incidence of psychotic disorder in urban probably caused a correspondingly higher incidence of presbycusis. So the prevention and cure of some age-induced diseased (e.g. hypertension, arteriosclerosis and diabetes) may be helpful to release and improve presbycusis.

Aged↗
PubMed2001

[Extraction of the antioxidative substances from Chinese rose and its antioxidative effect on lard].

The antioxidative effect of extracts from Chinese rose was measured with Na2S2O3-I2 titrimetric method by using lard as substrates. It was found that the antioxidative activities of the Chinese rose extracts retrieved by 95% ethanol solution were the highest, and the activities were strengthened with the increase of dosage. Citric acid and amino acid showed synergistic effects in antioxidative activities with extracts of Chinese rose. Ascorbic acid and alpha-tocophrol also showed strong synergistic antioxidative effect with the extracts of Chinese rose. The combined antioxidative activities were higher than the activity of tea polyphenols, and almost as good as that of tertiary butyl P-dihydroxy bengene(TBHQ).

Antioxidants↗
PubMed2001

[A simple X-ray TV picture freezer].

A simple X-ray TV picture freezer, with just 5 chips of LSIC, is discussed in this paper. Its VRAM block is made up of cheap and relatively lower speed large scale SRAM. The memory block works in alternate mode and can meet the sample speed up to 10-12 Msps and the pixel matrix of 512 x 512.

Electricity↗
PubMed2001

[Pharyngeal passage tube treatment for obstructive apnea syndrome].

OBJECTIVE: To investigate the therapeutical effect of pharyngeal passage tube for OSAS. METHODS: Fifty-seven patients were treated during May 1995 to August 1999. All patients were examined by GKD-405 A polysomnography for apnea index (AI), hypnea index (HI), AHI (AI + HI) at cetera 7 items index before and after pharyngeal passage tube treatment. RESULTS: After treatment, the longest time of apnea shortened from (54.82 +/- 20.83) s to (25.74 +/- 9.50) s, the AHI lessened from 70.82 +/- 18.06 to 30.00 +/- 10.10, the oxygen desaturation increased from (62.36 +/- 11.53)% to (78.68 +/- 12.09)%. After treatment, the recorded parameters showed obvious therapeutical effect (P < 0.05-0.001, t values is from 2.20 to 15.29, the snore loudness of all patients dropped from (84.32 +/- 18.51) dB to (32.64 +/- 10.16) dB. The therapeutical successful rate was 87.72%. The long-term use rate (over 6 months) was 72.73%. CONCLUSION: The pharyngeal passage tube has obvious effect for patients suffering from severe OSAS. It is recommended for the treatment of OSAS as a conservative method.

Adult↗
PubMed2001

[Surgery of the skull base assisted by sinus endoscope].

OBJECTIVE: To explore the feasibility and clinical value of the endoscopic operations around the skull base. METHODS: A retrospective study was made of 44 cases treated by endoscopic operations. Twenty-five cases underwent intranasal endoscopic operations. RESULTS: Forty of 44 cases were cured by one-stage surgery. One case of cartridge foreign body clamped in clivus was not successfully removed; only window operation and puncture biopsy were done in another case of pituitary adenoma; high cranial pressure has not been completely reduced after operation in the third case with relapsing craniopharyngioma a companied with obstructive hydrocephalus. One case of sphenoidal malignant adenoma involving saddle based and extended laterally was partly resected. Complications were follows: cerebrospinal fluid rhinorrhea in 2 cases, diabetes insipidus in 1 case, all of them were cured by conservative treatment; nasal septum perforation in 1 case, without any treatment. CONCLUSIONS: The endoscopic skull base surgery by intranasal approach is feasibility. Intranasal approach has direct path, slight wound and no wound in face. Combined with operation microscope, sinus endoscope can make up for its limits.

Endoscopy↗