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Biomedical subjects

H S Fang

Publications and source records attributed to H S Fang.

At least 19 recordsLinked to original sources
PubMed2000

[Detection of impurities in DNA samples by using the convolution spectrum method].

AIM: To detect the presence of phenol, amino acids and endotoxin in DNA preparations. METHODS: By using the convolution curve transformation technology, correlation coefficient discriminant which was put forward by spectrum space theory and computer information process technology, impurities in DNA samples were detected. RESULTS: The convolution spectrum method compared with A260/A280 ratio method and second-derivative absorption spectrum method could be used for the semiquantitative determinations of impurities in DNA samples and the results were satisfactory. CONCLUSION: The method was simple, convenient, fast and valuable to the biochemical analysis.

Amino Acids↗
PubMed2000

[Determination of major components in liuyingwan pills by supercritical fluid extraction(SFE)].

OBJECTIVE: On the basis of SFE and CGC to establish a method for the qualitative and quantitative analysis of major components in Liuyingwan pills. METHOD: Orthogonal design and variance analysis were used to optimize the four variables (temperature, pressure, volume of modifier and static extraction time) of SFE, and the quantification was completed by CGC. RESULT: The optimized conditions are as follows: pressure 48.2 MPa, temperature 60 degrees C, 0.2 ml ethyl acetate as modifier and static extraction 10 min. The recoveries of borneol and eugenol are 101.93% (RSD 1.56%) and 98.43% (RSD 2.26%) respectively. CONCLUSION: Compared with conventional methods, SFE is rapid, convenient and accurate in determining borneol and eugenol.

Camphanes↗
PubMed2000

[Determination of major components in Psoralea corylifolia L. by using supercritical fluid extraction (SFE)].

A method based on SFE and CGC has been developed for qualitative and quantitative analysis of major components in Psoralea corylifolia L.. The orthogonal design method and the analysis of variance are used to optimize the five variables (temperature, pressure, volume of modifier, static extraction time and CO2 dynamic extracting volume) of SFE and the optimized conditions listed as follows: temperature 70 degrees C, pressure 38.5 MPa, static extraction 1 min, dynamic extraction 7 mL and 60 microL CHCl3 as modifier. The recoveries of psoralen and isopsoralen are 96.93% (RSD 1.87%) and 98.43% (RSD 2.06%) respectively. Being compared with conventional methods, the SFE as an alternative technique for sample preparation will be most useful in the quality control of Chinese traditional medicines.

Chromatography, Gas↗
PubMed1991

Effects on renal excretion in rats after injection of bile extracts from some fresh-water fish.

Bile acid extracts were prepared from grass carp, bighead, common carp, milk fish and tilapia. Injection of the fish bile extracts (3.6 mg/kg, i.v.) into rats increased renal excretion of water, sodium and potassium; decreased blood pressure; and hemolyzed RBCs. The diuretic, natriuretic, hypotensive and hemolytic actions of the bile extracts were stronger in grass carp, bighead and common carp, moderate in milk fish, and weakest in tilapia.

Animals↗
PubMed1991

Effects of atrial natriuretic factor in chronic hypoxic spontaneously hypertensive rats.

The present study was designed first to investigate the pulmonary hypertensive effects of chronic hypoxia in spontaneously hypertensive rats and second to compare the cardiovascular effects of atrial natriuretic factor on rats exposed to hypoxia and on control rats kept at sea level. Catheters were placed in the femoral and pulmonary arteries for measurement of mean systemic arterial pressure and mean pulmonary arterial pressure. The cardiac output was measured by thermodilution method. It was found that 4 weeks of simulated 18,000-foot hypoxia led to polycythemia, right ventricular hypertrophy, and pulmonary hypertension, which resulted from an increased pulmonary vascular resistance. However, systemic arterial pressure was not significantly different between the two groups of rats. Atrial natriuretic factor administration decreased systemic arterial pressure and pulmonary arterial pressure to a lesser extent in the hypoxic group compared with the sea level control group. It is concluded that these animals showed an impaired response to atrial natriuretic factor after long-term exposure to hypoxia.

Animals↗
PubMed1990

The renal functions following a profound hypothermia in rats.

The aftereffects of renal function were studied in rats exposed to profound hypothermia and 5 min of cardiac arrest. All experimental rats were reanimated and survived at least 1 week. It was observed that the water intake and the basal renal excretion of urine, potassium and urea were decreased 24 hr after cooling, but did return to normal within 1 week. The renal handling of a large volume of infused saline was retarded 4 hr but recovered by the end of 24 hr after hypothermia. At both 4 and 24 hr after deep cooling, clearance of inulin and p-aminohippuric acid showed there were no change in glomerular filtration rate and effective renal plasma flow. It was concluded that the renal function was altered shortly after deep cooling and 5 min of cardiac arrest, however, this alteration could be completely recovered thereafter.

Animals↗
PubMed1987

The renal functions following a severe hypoxia in conscious rats.

The aftereffects of renal function were studied in rats exposed to hypoxia at 35,000 ft simulated altitude for 60 min. It was observed that the renal handling of a large volume of infused saline was retarded 4 hr after hypoxia, but it was nearly recovered by the end of 24 hr after exposure to severe hypoxia. However, the urine output, plasma and urine electrolytes, and renal hemodynamics were not significantly altered in hypoxic rats. A high mortality of rats exposed to such a low oxygen tension is also reported.

Altitude↗
PubMed1987

Renal functions following hyperbaric oxygen toxicity in conscious rats.

The after-effects of renal function were studied in rats exposed to hyperbaric oxygen (HBO) at either 4.8 ATA for 60 min or 6.8 ATA until the onset of convulsions. Only the rats which suffered from HBO convulsions were found to have alterations in renal function. It was observed that 4 hr after convulsions, there was a decrease in urinary excretion of urea and creatinine, which resulted in an elevation of blood urea nitrogen (BUN) and creatinine. Clearances of inulin and p-aminohippuric acid showed a decrease in the glomerular filtration rate and effective renal blood flow 4 hr after HBO convulsions. These parameters nearly returned to normal in 24 hr after convulsions. The renal handling of a large volume of infused saline was also retarded 4 hr after HBO convulsions, but by the end of 24 hr after HBO convulsions, it was much improved. Therefore, it was concluded that the renal function was altered after HBO convulsions, but nearly recovered in 24 hr.

Animals↗
PubMed1987

Decompression and occurrence of cataract in enucleated eyes of experimental animals.

Chamber flight at a simulated altitude of 58,000 ft (17,680 m) or more caused marked lens opacities in enucleated eyes of the experimental animals. After descent to ground level, the opacity could subsequently be regressed despite complete deprivation of blood supply to the eye. The present finding suggests that decompression might play an important role in inducing such a cataract.

Animals↗
PubMed1985

Further studies on the application of the compartmentalization/airlock concept to aircraft and spacecraft.

The effect of the application of the compartmentalization/airlock on accidental decompression was studied in conscious rats, mice, and guinea pigs. It was observed that in unprotected rats and mice, 78 of 102 middle ears (76.5%) exhibited hemorrhages with their eardrums intact; and in unprotected guinea pigs, 37 of 50 eardrums (74%) revealed rupture associated with hemorrhages of all middle ears (100%). Seven cases of malleus fractures (14%) were also found in unprotected guinea pigs. On the other hand, none of the protected animals showed signs of middle ear barotrauma. The protective effect on the tolerance of middle ears in the present study showed the same tendency as that on the tolerance of lungs in our previous study. These findings indicate that the application of the compartmentalization/airlock would be of great value in protection against accidental rapid decompression of pressurized aircraft and spacecraft.

Aircraft↗
PubMed1984

Bubble formation of aqueous humor and lens opacity during chamber flight.

A transparent miniature decompression chamber was placed on the stage of a large-working zoom-stereo microscope so that the effect of decompression on the frog eye could be microscopically observed and photographed. It was found that chamber flight at a simulated altitude of 66,000 ft (20,117 m) or more caused bubble formation in aqueous humor and lens opacities in some of the experimental animals. On return to ground level, the bubbles either decreased in size or completely disappeared. The cataract could also regress after recompression to 1 atm. Such lens opacities may be termed altitude cataract, instead of asphyxial or anoxic cataract.

Aerospace Medicine↗
PubMed1984

Application of the compartmentalization/airlock concept to aircraft and tolerance of lung to rapid decompression.

The incidence of pulmonary hemorrhage of different laboratory animals undergoing rapid decompression was found to be markedly decreased by applying the compartmentalization/airlock concept to simulated pressurized aircraft. It was observed that, in protected rabbit, mouse, and rat lungs, 6 of 24 (25%), 7 of 24 (29%), and 6 of 24 (25%), respectively, exhibited a few petechial hemorrhages following rapid decompression. In unprotected animals, however, all 72 lungs showed slight-to-very-severe degrees of decompression-induced hemorrhages. The percent of mortality of the unprotected animals undergoing rapid decompression was 47%, while there were no deaths in protected animals. The incidence of such pulmonary hemorrhages and the mortality of experimental animals indicate that compartmentalization, combined with an adequate airlock, would be of great value in protection against accidental decompression of pressurized aircraft.

Aircraft↗
PubMed1983

Tuberculosis of the upper cervical spine.

Six patients, aged between 3 and 51 years, with tuberculosis of the upper cervical spine were studied. Prominent features of the disease included pain and stiffness, paralysis, swelling of the retropharyngeal soft tissue, osteolytic erosions, and atlanto-axial subluxation. Cure was obtained with antibiotics, transoral decompression and C1-2 fusion.

Adolescent↗
PubMed1982

The effects of thermal injury on gastrointestinal motor activity in the rat.

Gastrointestinal motor function was studied in conscious rats. The gastric emptying time, small intestinal motility and the colonic transit time were measured. A burn injury, covering about 15 per cent of the body surface area was applied to experimental animals; control animals received a mock burn. Burn injury caused a marked inhibition of gastrointestinal motility. This inhibition was significantly improved by a continuous saline infusion, but saline infusion alone had no effect on the gastrointestinal propulsive motility of normal rats.

Animals↗