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Biomedical subjects

W Wang

Publications and source records attributed to W Wang.

At least 343 records · Page 19Linked to original sources
PubMed2001

Prevention of debris flow disasters on Chengdu-Kunming Railway.

Chengdu-Kunming Railway is an important transport line on southwestern China. However, this railway's safety is often threatened by debris flows. How to effectively forecast and alarm the debris flow disasters and reduce the losses is the aim to study the prevention system in this paper. The factors to cause or influence debris flow are divided into four parts--the basin environmental factors, the basin meteoric factors, the prevention work's elements and the flood-relief work's elements, and the prevention system is made up of three models--a judgment model to assess the debris flow gully's seriousness, a forecast model to predict the debris flow's occurrence and an alarm model to evaluate the debris flow's disaster. Afterwards, a concise structure chart is worked out and verified by the field data from Chengdu-Kunming Railway. This prevention system will provide beneficial reference for the debris flow's monitoring network to be executed on Chengdu-Kunming Railway.

China↗
PubMed2001

[The trend of incidence rate of acute stroke event in urban areas, Beijing from 1984 to 1999].

OBJECTIVE: To estimate the trend of incidence rate of acute stroke event in the population aged 25-74 in urban areas of Beijing from 1984 to 1999. METHODS: All stroke events in defined population were ascertained and validated according to unified protocol and criteria. A total number of 6,553 stroke events were analyzed, crude rates and aged-standardized rates for all stroke events and first-ever stroke events were calculated for whole calendar years for the population. Temporal annual rates of stroke were estimated for 16 years. RESULTS: Annual stroke attack rates increased both in men and women with an average annual percentage changes 4.5% and 4.2%, respectively. Annual first-ever stroke incidence rate increased both in men and women with average annual percentage changes 4.1% and 4.2%, respectively. Most remarkable increase was noticed in the 65-69 and 70-74 age groups. CONCLUSION: Rates of stroke attack incidence and first-ever incidence were increasing in the population of urban in Beijing, indicating the prevention of stroke be strengthened in the area.

Adult↗
PubMed2001

Determination of estradiol metabolites in human liver microsome by high performance liquid chromatography-electrochemistry detector.

AIM: To constitute a method to determine the estradiol metabolites in human liver microsome in low concentration of estradiol. METHODS: Use high performance liquid chromatography after solvent extraction, evaporation, and reconstitution to separate the metabolites and use a electrochemistry detector to detect the metabolites. RESULTS: With a mobile phase of acetic acid buffer-acetonitrile (50:50, v/v, pH 4.5) at flow rate of 1.0 mL/min and a potential of +0.7 V vs Ag/AgCl, all six composition were well separated and satisfactorily detected. There are E3, 16alpha-OHE1, 2-OHE2, E1, and two unidentified composition. The minimum detectable amount is about 100 p g on column. This method is sensitive enough to detect E1 in a substrate concentration of 1 micromol/L. CONCLUSION: The method can be used to study the metabolism mechanism of estradiol in liver microsome.

Adult↗
PubMed2001

[Caloric value and energy allocation of Chloris virgata in northeast grassland].

The rules of seasonal changes in caloric values of individual plant, stem, and leaves of Chloris virgata were similar, which had two peak values from early July to early August, and then decreased gradually. Those of inflorescence assumed U shape, and had two peak values in early August and middle September, respectively. The seasonal changes in caloric values of dead standing were irregular, and the maximum value was appeared in early August. The seasonal changes in existent energy value of the aboveground parts in Chloris virgata population presented double peak curve. The two peak values were appeared in early August and early September respectively, and the maximum value was 7381.27 kJ.m-2 in early September. The energy allocation in different seasons was leaf > stem in early July, stem > leaf > dead standing in middle July, stem > leaf > inflorescence > dead standing in August, stem > inflorescence > leaf > dead standing in early September, and stem > inflorescence > dead standing > leaf in middle September. The vertical structure of energy in the aboveground parts was that the energy value gradually increased from the earth's surface to 20 cm high, and then decreased. The maximum value, which accounted for 25.75% of energy in the aboveground parts, was appeared in the layer of 10-20 cm high. In the underground parts, the energy value progressively decreased with the increase of depth, and the maximum value, which accounted for 74.21% of energy in the underground parts, was appeared in the layer of 0-10 cm depth.

Energy Metabolism↗
PubMed2001

[Acidity and acid buffering capacity of aerosols during sand-dust storm weather in Beijing].

In the spring of 2000, there were 12 sand-dust storms in Beijing. 2 sand-dust storms were experienced in time and mass concentrations, elementary concentrations acidity and acidic buffering capacity of TSP(Total Suspended Particulate, < 100 microns) and PM10(Inhalable particulate, < 10 microns) were sampled and analyzed. Results showed that pollution level of aerosols was extremely high. However, the acidity of aerosols was relatively low and the aerosols had very strong acid buffering capacity for acidification. Therefore, the aerosols brought about by the sand-dust storms could avoid the occurrence of acidic precipitation to some extent.

Acids↗
PubMed2001

[Analysis, prospect and treatment of causes of phacoemulsification complications].

OBJECTIVE: To analyse the causes of different complications of phacoemulsification and to investigate their principles of treatment and prevention. METHOD: The causes of different complications in 187 (180 cases) of 2,250 eyes having undergone phacoemulsification were analyzed. RESULTS: Intraoperatively, the common complications of phacoemulsification were posterior capsular rupture in 70 eyes (3.1%), iris damage in 16 eyes (0.7%), iris prolapse in 6 eyes (0.3%), drop of lens fragments into vitreous in 3 eyes (0.1%) and tear of Descernent's membrane in 4 eyes (0.2%). The common complications after the operation were corneal endothelial edema in 89 eyes (4.0%), corneal decompensation in 2 eyes (0.1%), temporary intraocular hypertension in 28 eyes (1.2%), pupillary dilatation in 7 eyes (0.3%), retinal detachment in 8 eyes (0.4%), cystoid macular edema in 24 eyes (1.1%) and displacement of intraocular lens in 8 eyes (0.4%). CONCLUSIONS: The different complications can be diminished following the popularization and development of phacoemulsification. It should be properly managed once the complication has occurred, and good operative effects can be obtained.

Eye Diseases↗
PubMed2001

[Accidental perforation of the globe during peribulbar injection].

OBJECTIVE: To evaluate clinical manifestations, management, visual outcome and prevention of accidental penetration of the globe during peribulbar injection. METHODS: The medical records of 12 cases were retrospectively reviewed. The disposable needle was used in all the cases except one to whom a reusable needle was applied. Lidocaine was injected in 2 cases, steroid or steroid combined with antibiotics was injected in the remaining ones. RESULTS: The main symptoms were acute loss of visual acuity (VA) and pain in the involved eye. The signs included vitreous hemorrhage, white steroid material in the vitreous cavity, retinal break and detachment, high intraocular pressure or hypotony and rupture of cataract surgical wound. The treatments consisted of vitrectomy, the repair of retinal detachment or ruptured cataract surgical wound. Six cases ended with VA < or = 0.05. CONCLUSION: Inadvertent intraocular perforation during peribulbar injection is a serious complication. The best method to rescue such cases is prevention.

Adult↗
PubMed2001

Retinoic acid regulated insulin-like growth factor gene expression in cord blood lymphocytes.

OBJECTIVE: To explore the immune promotion mechanism of retinoic acid (RA). METHODS: Reverse Transcription-Polymerase chain reaction (RT-PCR) was used to detect the gene expression of insulin like growth factor I (IGF-I) and IGF receptors (IGF-IR and IGF-IIR) in vitro, and their regulation by RA in human cord blood lymphocyte (CBL). RESULTS: Significant upregulation of IGF-I, IGF-IR and IGF-IIR mRNA was found at 6-24 hours in CBL incubated with physiologic concentrations of RA as compared to those without RA. CONCLUSION: The enhancement of IGF expression may be an important pathway for vitamin A to promote immune cellular functions.

Cells, Cultured↗
PubMed2001

Clinical manifestations of AIDS with cryptococcal meningitis.

OBJECTIVE: To increase the awareness of AIDS with cryptococcal meningitis. METHODS: Eighteen cases of confirmed AIDS with cryptococcal meningitis in the Bata Regional Hospital, Equatorial Guinea from January 1997 to November 1999 were analyzed. RESULTS: The clinical manifestations of the 18 cases were: insidious onset, fever, severe headache, generalized pain, nausea and vomiting, weight loss and dehydration, and enlarged cervical lymph nodes. Boa's and Cullen's signs were positive. The positive rates of cerebrospinal fluid (CSF) India ink stain and the polysaccharide capsule antigen (ELISA) were 77.8% and 99.4%, respectively. The positive rate of CSF culture of cryptococcus was 100%. The mortality rate was 83.3%. CONCLUSION: Cryptococcal meningitis is the most common opportunistic infection and one of the major causes of deaths in AIDS patients. The misdiagnosis and mortality rates were very high and could be explained by a lack of awareness for the occurrence of AIDS with cryptococcal meningitis, late presentation, serious illness and severe complications, and delayed and inadequate therapy.

AIDS-Related Opportunistic Infections↗
PubMed2001

Efficacy of dihydroartemisinin-mefloquine on acute uncomplicated falciparum malaria.

OBJECTIVE: To evaluate the clinical efficacy of dihydroartemisinin-mefloquine on acute uncomplicated falciparum malaria. METHODS: Fifty-four patients with symptomatic falciparum malaria were allocated to receive oral dihydroartemisinin at a single dose of 120 mg on day 1, followed by mefioquine, 750 mg and 500 mg on days 2 and 3, respectively. Follow-up was performed on days 1, 2, 3, 4, 7, 14, 21, and 28. RESULTS: All patients had a rapid initial response to treatment. The parasite clearance time (PCT) after treatment was 30.7 +/- 3.6 hours. The fever subsidence time (FST) after treatment was 21.2 +/- 2.8 hours. Two patients had a recrudescence 21 and 25 days respectively after the disappearance of parasitemia, hence the recrudescence rate was 3.7% and the cure rate was 96.3%. No serious adverse effects were observed, only mild and transient nausea, vomiting and loss of appetite. CONCLUSION: A combination of dihydroartemisinin and mefloquine is effective in the treatment of acute uncomplicated falciparum malaria.

Acute Disease↗
PubMed2001

Clinical, brain electric earth map, endothelin and transcranial ultrasonic Doppler findings after hyperbaric oxygen treatment for severe brain injury.

OBJECTIVE: To analyze the effect and mechanism of hyperbaric oxygen (HBO) treatment for severe brain injury (SBI). METHODS: Fifty-five patients were divided into a treatment group of 35 patients and a control group of 20 patients. We observed the alterations of clinical, brain electric earth map (BEAM), endothelin (ET) and transcranial ultrasonic Doppler (TCD) findings before and after HBO treatment as well as outcome. RESULTS: In the treatment group, Glasgow coma scale, BEAM and outcome improved after HBO treatment; compared with that of the control group, it showed a significant difference. After one course of treatment, treatment group ET was reduced from 91.24 +/- 12.18 ng/L to 68.88 +/- 14.37 ng/L (P < 0.01); in control group, ET was reduced from 90.78 +/- 15.71 ng/L to 83.12 +/- 12.22 ng/L, with a statistically significant difference (P < 0.05). TCD records of MCA mean velocity (Vm) was reduced from 64.2 +/- 4.8 cm/s to 51.6 +/- 4.2 cm/s (P < 0.01), and a decrease in MCA systolic velocity (Vs) and pulse index (PI) values was statistically significant (P < 0.01). CONCLUSION: HBO treatment can improve the clinical, BEAM and outcome of severely brain injured patients, by decreasing acute stage ET and improving the blood velocity of MCA and decreasing cerebral vascular resistance. HBO treatment can reduce cerebral vascular spasms, cerebral ischemia and hypoxia. One of the important mechanisms of HBO treatment for severe brain injury is the lowering of intracranial pressure.

Adult↗
PubMed2001

[A study on cyclooxygenase-2 protein expression in esophageal carcinoma and premalignant lesions].

OBJECTIVE: To investigate cyclooxygenase-2(Cox-2) protein expression in esophageal cancer and precancerous lesions. METHODS: One hundred twenty biopsy specimens from patients with esophageal carcinoma, 113 from patients with esophageal premalignant lesions, 27 from individuals with normal esophageal mucosa and 3 from Barrett's esophagus were examined for Cox-2 protein expression by immunohistochemistry. RESULTS: Cox-2 protein was not observed in normal esophageal squamous and glandular epithelium, hyperplasia from mild to severe dysplasia lesions and carcinoma in situ. Positive Cox-2 expression was found in 4 of 60 specimens of invasive squamous-cell carcinomas, 21 of 30 specimens of esophageal adenocarcinomas and in 3 of 3 Barrett's esophageal tissues. CONCLUSION: The Cox-2 protein expression may be associated with the development of the esophageal adenocarcinomas but not esophageal squamous-cell carcinomas.

Adenocarcinoma↗
PubMed2001

[Treatment of stage II non-Hodgkin's lymphoma: analysis of 268 patients].

OBJECTIVE: To seek the optimum treatment for patients with stage II non-Hodgkin's Lymphoma (NHL). METHODS: 268 patients with stage II NHL, treated from January 1987 to December 1993, received radiation alone (R-50), radiation plus chemotherapy (R + C - 73), chemotherapy followed by radiation then by chemotherapy (C + R + C - 72), chemotherapy plus radiation (C + R - 61) or chemotherapy alone (C-12). A total of 206 patients was treated with combined treatment. RESULTS: The 1-, 2-, 3-, 4-, 5- and 6-year survival rates were 95.1%, 87.8%, 87.8%, 85.4%, 82.9%, 53.6% in C + R + C group for patients with stage II high grade NHL, which were much better than those in the R group, R + C group and C + R group (P < 0.01). For patients with stage II intermediate grade NHL, the 1-, 2-, 3-, 4-, 5- and 6-year survival rates were 89.3%, 75.0%, 67.8%, 60.6%, 57.1%, 46.4% in the C + R + C group, which were better than those in the R group, R + C group and C + R group (P > 0.05). However, for patients with low grade NHL, the survival rates were similar both in the R group and the combination groups. CONCLUSION: For patients with stage II intermediate and high grade NHL, combination therapy of C + R + C is recommended. Radiation alone can only be used for patients with stage II low grade NHL.

Adolescent↗
PubMed2001

An experimental study on drugs for improving blood circulation and removing blood stasis in treating mild chronic hepatic damage.

Large and small doses of drugs for improving blood circulation and removing blood stasis were used in model rats to treat mild chronic hepatic damage induced by carbon tetrachloride (CCl4). The results show that large dose of Dang Gui ([symbol: see text] Radix Angelicae Sinensis) and Dan Shen ([symbol: see text] Radix Salviae Miltiorrhizae) (drugs for regulating blood flow) and small dose of Yu Jin ([symbol: see text] Radix Curcumae) and Niu Xi ([symbol: see text] Radix Achyranthis Bidentatae) (drugs for activating blood flow) can significantly elevate the activity of SOD (P < 0.05) and/or lower the T/K ratio, markedly reduce the MDA content (P < 0.05 or P < 0.01) and significantly decrease the activities of ALT and AST (P < 0.05 or P < 0.01), demonstrating that these drugs are effective in combating oxygen free radicals (OFR) in chronic liver damage. On the contrary, large dose of Tu Bie Chong ([symbol: see text] Eupolyphaga seu Steleophaga) and E Zhu ([symbol: see text] Rhizoma Curcumae) (drugs for removing blood stasis) tend to increase the ALT and AST (P < 0.05) activities. The results suggest that the synergism of elevation of the SOD activity and reduction of T/K ratio contributes to the action of drugs for improving blood circulation and removing blood stasis in combating the liver damage induced by CCl4.

Alanine Transaminase↗
PubMed2001

Surface keratopathy after penetrating keratoplasty.

PURPOSE: To determine the type and prevalence of epithelial abnormalities in the intermediate postoperative period after penetrating keratoplasty and to define the donor and recipient variables that influence the status of the graft epithelium. DESIGN: Prospective cohort study. METHODS: We prospectively followed the clinical course of 80 patients after penetrating keratoplasty. We monitored the status of the corneal epithelium for 3 months after surgery using slit-lamp biomicroscopy and fluorescein staining of the epithelium. Donor characteristics, recipient preoperative and postoperative variables, and postoperative medications were recorded. Epithelial abnormalities were analyzed against these variables by using univariate and combined statistical models to determine the impact of each variable on postoperative epithelial pathology. Main outcome measures included punctate keratopathy, macro-epithelial defects, hurricane keratopathy, rim defects, and filamentary keratopathy. RESULTS: Sixty-three percent of all patient visits demonstrated punctate epithelial keratopathy (PEK). Hurricane keratopathy (51%) and filamentary keratopathy (14%) constituted the next most commonly observed abnormalities. Older recipient age and the use of topical antibiotics were associated with a higher prevalence of punctate epithelial keratopathy. The odds ratio (OR) for a 1-year increase in age is 1.0276 (95% CI, 1.1013-1.0442), and the OR for using topical antibiotics is 6.9028 (95% CI, 3.1506-15.1239). Use of topical ofloxacin and increased time after surgery were associated with lower prevalence of punctate keratopathy; ORs were 0.9806 (95% CI, 0.9736-0.9876) and 0.3662 (95% CI, 0.1688-0.7943), respectively. Decreased corneal sensation and the presence of anterior blepharitis preoperatively were associated with an increase in hurricane keratopathy; ORs were 8.8265 (CI, 2.3837-32.6835) and 3.2815 (CI, 1.7388-6.1931), respectively. Total storage time for the donor material was also associated with an increased prevalence of hurricane keratopathy (OR, 1.0316; CI, 1.0052-1.0220). Patients with rim defects and macro-epithelial defects were more likely to have antibiotic and topical lubrication prescribed. No specific variable was found to have a significant association with filamentary keratopathy, except possibly for death-to-preservation time, which had a P value of .0587. CONCLUSIONS: Surface keratopathy is one of the most common complications of keratoplasty. Our study demonstrates that older age, preoperative lid disease, and decreased preoperative corneal sensation appear to increase the probability of clinically significant epithelial surface abnormalities after keratoplasty. Recognition of these risk factors in advance of surgery will alert the surgeon to the need for appropriate management.

Adolescent↗
PubMed2001

[Clinical analysis of 1,827 patients with reflux esophagitis].

OBJECTIVE: To investigate clinical and endoscopic characteristics of reflux esophagitis (RE) in Chinese. METHODS: 1 827 patients with RE, diagnosed by endoscopy in the past 10 years, were divided into different grades according to Los Angeles System and Chinese Standard. A part of them underwent esophageal manometry, 24-hour pH monitoring, and 24-hour bilirubin monitoring. The relationship between age, sex, symptom, accompanied diseases and each examinations were analyzed. RESULTS: RE was 2.02% of the total endoscopy number, and male vs female was 3.9:1, mean age was (52.02 +/- 14.38) years old. Only 36.29% of RE patients have typical reflux symptom. Patients with light mordent (Los Angeles System A, B and Chinese Standard I) RE were more than those with severe RE. Both of the time of esophageal acid exposure and total percent time bilirubin absorbance >or=0.14 for RE was significantly more than normal (P < 0.01). CONCLUSION: The incidence of RE in Chinese is lower than that in Western and the severity is less. Most of RE are male and aged. There is a close association between RE and both of gastroesophageal reflux and duodenogastroesophageal reflux. Endoscopy is very important for diagnosis of RE.

Adolescent↗
PubMed2001

[The natural history of electrophysiological and magnetic resonance changes of subacute combined degeneration].

OBJECTIVE: To observe the presentations and in the patients with subacute combined degeneration (SCD) changes of electrophysiology (EP) and magnetic resonance image (MRI) before and after treatment and to analyze their values in diagnosis. METHODS: 10 patients received a series of examinations, including clinical neurological functions, serum vitamin B12 and folic acid concentrations, spinal cord MRI, peripheral nerve conduction velocity, sensory evoked potential (SEP) and visual evoked potential(VEP). They were followed up for 3 to 36 months. The changes of spinal cord MRI and SEP before and after the treatment were studied. RESULTS: After Vitamin B12 therapy, all the patients improved,but there were still some abnormalities of SEP left. The lesions could be shown sensitively by EP. The changes of SEP and clinical symptoms correlated with each other. The spinal cord MRIs of most patients showed the lesions objectively, demonstrating primarily long-tape abnormal signals in posterior and lateral columns, iso-intense on T1 and hyper-intense on T2 without contrast. Most lesions were seen at the thoracic cord. The lesions constricted or disappeared when the clinical conditions improved. CONCLUSION: Spinal cord MRI and EP could objectively show the lesions of SCD and the change before and after the treatment. These examinations and the follow-up of disease could be helpful in the diagnosis of SCD.

Adult↗