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Biomedical subjects

B Z Xu

Publications and source records attributed to B Z Xu.

5 recordsLinked to original sources
PubMed1991

Visual evoked potential measurement by maximum length sequence technique.

The maximum length sequence (MLS) technique is applied to improve data collection of a clinically important long latency visual potential. Given a limited time for measuring the response and with low number of stimulus presentation, the MLS technique exceeded the conventional method of ensemble averaging in attaining a higher signal-to-noise ratio (SNR). The theoretical consideration of such improvement is developed along with the system implementation. Typical examples of the results obtained in a human subject are presented.

Algorithms↗
PubMed1991

[Breeding grass carp against mosquitoes in rice field].

In this experimental study, grass carp were bred in rice field (1.9 fish/m2) to control mosquito larvae. 78 days after treatment, the larvae population of An. sinensis and Cu. tritaeniorhynchus dropped down by 87.4% and 80% respectively. Newly hatched 1-2 instar larvae accounted for 73.3% of the larvae remained in rice field after treatment. Eighty-nine samples of fish feces taken from rice field and 10 fishes were examined for breathing syphons of mosquito larvae. Breathing syphons were found in 22 fecal samples (24.7% positive) and 3 fishes (30% positive). The average number of mosquito larvae devoured by one fish was 861.5 in 24 hours in tap water and 661 in 24 hours in water containing grass and aquatic plants. The simulated field test showed that the average number of mosquito larvae devoured by fish was 362 larvae in 24 hours. The field trial indicated that the grass carp could not only cut down the mosquito larvae population but also benefit the peasants by increasing the production of both fish and rice.

Animals↗
PubMed1988

Study and clinical application of a porcine biomembrane for the repair of dural defects.

A biomembrane was developed from pig peritoneum treated with 0.65% glutaraldehyde. This was evaluated for use as a dural substitute in an animal model and in a patient population. After being treated with the glutaraldehyde solution, the biomembrane lost its antigenicity while its collagen underwent an irreversible cross-linking reaction, causing it to become a stable nonviable polymer resistant to absorption by the host. The biomembrane was used experimentally in 43 procedures on 20 dogs and was applied clinically in 614 patients. The results demonstrated that it is an acceptable material for the repair of dural defects, with the following advantages: 1) it is nontoxic to the body and brain tissues, with minimal tissue reaction; 2) its biophysical properties facilitate watertight closure with sutures; 3) its distensibility makes it suitable for decompressive surgical dural repair; and 4) its visceral surface is extremely smooth, causing virtually no adhesions with the brain tissue while the outer surface readily heals with the subcutaneous tissue.

Adolescent↗
PubMed1987

Floating bait formulations increase effectiveness of Bacillus thuringiensis var. israelensis against Anopheles larvae.

The development and screening of floating-type bait formulations designed to improve the activity of bacterial toxins against larval Anopheles is described. Floating and spreading abilities of carrier particles (wheat flour) were compared using corn oil, lecithin, and two products yielding surface films on water (Arosurf and Liparol). Mixtures containing 1 or 5% Arosurf showed the best spreading abilities on a water surface, but strongly inhibited the ingestion of wheat flour by Anopheles albimanus larvae. Corn oil and lecithin improved spreading satisfactorily at a concentration of 5% and inhibited larval feeding by only 6-25%. To select a suitable concentration of active ingredient in formulations, Bacillus thuringiensis var. israelensis (B.t.i.) primary powder in concentrations ranging from 0.01 to 0.5% was mixed with wheat flour/corn oil mixtures and tested in quantities exceeding the gut volumes of treated larvae. Complete mortality was obtained with concentrations of 0.1% (Anopheles stephensi), 0.2% (An. albimanus), or 0.3% (An. quadrimaculatus) B.t.i. When in 175-liter containers the activity of formulations (5% corn oil, 0.2% B.t.i.) and of toxin suspensions was compared by conventional dosage-mortality regression, formulations were more active by a factor of 68 against An. stephensi, 39 against An. albimanus and 67 against An. quadrimaculatus.

Animals↗