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Biomedical subjects

Z Li

Publications and source records attributed to Z Li.

At least 829 records · Page 46Linked to original sources
PubMed1999

[Application of high performance liquid chromatography to the study on the production of maltooligosaccharide by synergistic action of two-enzymes].

This paper describes the application of high performance liquid chromatograpy to the study on the production of maltooligosaccharide by synergistic action of two-enzymes. Seven sugars in products were separated on a column of Nucleosil C18 with water as the mobile phase and determined refractometrically. Meanwhile, for the preparation of maltooligosaccharide, the effect of supplementing rate of the two enzymes on the content of maltooligosaccharide in products is examined in this paper. The optimun technological conditions were obtained by using the orthogonal design and the amount of the two enzymes added was determined. Thus more than 70% of M3-M6 maltooligosaccharide in product was obtained.

Chromatography, High Pressure Liquid↗
PubMed1999

[An experimental study on the change of adhesion between leukocyte and endothelium in acute cerebral ischemia].

The objective of this experiment was to investigate the change of leukocyte adhesion in the focus of cerebral ischemia-reperfusion injury. Immune fluorescent microscope equipped with image tube camera and high speed recording TV sets was used to study the leukocyte adhesion in the focus of cerebral ischemia-reperfusion injury. The result showed that the density index of adherent leukocyte was significantly elevated, the fracture stress between leukocyte and endothelium dropped, and the adhesion increased in the focus of cerebral ischmic-reperfusion injury. These findings indicated that leukocyte adhesion was increased significantly and leukocytes played an important role in the cerebral ischemia-reperfusion injury.

Acute Disease↗
PubMed1999

[Prediction and estimation on molar response values of alkane using molecular subgraph].

A new method based on topographical subgraph of alkanes is proposed and used for molar response values of alkanes. A novel coding, which derived from the numbers of molecular subgraph, is used to characterize molecular structure of alkanes. It showed that there is a very good correlation between the coding and molar response values. The results of multiple linear regression are as follows. Molar response values (SM) on FID: SM = 89.579 - 56.579x1 - 40.579x2 - 18.191x 3 - 2.677x4 + 11.818x5 + 25.690x6 + 40.421x7 + 54.421x8 + 13.926x9 + 15.524x10 + 13.923x11 + 13.857x12 + 30.079x13 + 30.403x14 + 32.677x15 + 29.030x16, N = 50, r = 0.9983, S = 1.9342; Molar response values (SM) on TCD: SM = 139.799 - 62.251x2 - 49.214x3 - 31.244x4 - 15.992x5 + 0x6 + 13.201x7 + 27.201x8 + 11.152x9 + 9.225x10 + 8.427x11 + 10.041x12 + 22.452x13 + 14.977x14 + 22.318x16, N = 32, r = 0.9963, S = 1.7668. Where r, S and N are regression coefficient, residual standard deviation and data number, respectively. Having tested the modeling by using back-propagation neural network (BPNN) and leave-one-out method, we got the correlation coefficient of cross validation, 0.989.

Alkanes↗
PubMed1999

[The study of ethanol-water used as reversed-phase high performance liquid chromatographic mobile phase].

The viscosity of ethanol-water at various temperatures was determined. The physicochemical properties and characters of the solvents used as the mobile phase of reversed-phase high performance liquid chromatography(RP-HPLC) were compared between methanol and ethanol. The components of several Chinese medicines have been determined by RP-HPLC with ethanol-water used as mobile phase, and the results were compared with those obtained with methanol-water or acetonitrile-water. It showed that ethanol can be used as RP-HPLC mobile phase by increasing the column temperature moderately.

Chromatography, High Pressure Liquid↗
PubMed1999

[The isolation of microbe producing biosurfactants].

Microorganisms capable of producing biosurfactants can be isolated by a series of steps including hydrocarbon enrichment culture, hemolytic activity assay on blood agar plates and oil displacement activity assay etc. Ten strains(including bacteria, yeasts and fungi) were isolated with higher surface activity from 1000 samples from soil, sludge, waste water etc. Two strains of bacteria produced rhamnolipids and trehaloselipids respectively. One strain of bacterium produced long chain unsaturated carboxylic acid and another produced azelaic acid. Two strains of yeasts produced lipopolysaccharides with excellent emulsification property.

Bacteria↗
PubMed1999

[First discovery of Taenia saginata asiatica infection in Yunnan province].

AIM: To investigate the aetiology, species and epidemiological factors of Taenia infection in a pilot area of Lanping County, Yunnan Province. METHODS: Two patients with taeniasis were treated with antiscolex capsule and praziquantel, respectively. Five local weaning pigs free from tapeworm infection were fed with gravid proglottids obtained from the patients. After 2-3 months, the pigs were necropsied to examine cysticerci. In addition, one pig naturally infected with Taenia was treated as well. RESULTS: Based on morphological characteristics of the scolex and gravid proglottid of four tapeworms obtained from the patients, the worms were similar to T. saginata. 23 cysticerci recovered from two experimentally infected pigs were found in the livers, omentum majus and mesenterium, and 3 cysticerci were found in the liver and omentum majus in a naturally infected pig as well. The protoscolex of mature Cysticercus had two rows of rudimentary hooklets, one rostellum and four acetabula resembling to C. cellulosae. According to morphological characteristics and the location of cysticerci, the tapeworm was identified as Taenia saginata asiatia. CONCLUSION: T. saginata asiatica infection was first reported in Yunnan Province.

Adult↗
PubMed1999

[Observation on efficacy of artemether compound against vivax malaria].

AIM: To observe the efficacy of artemether compound against vivax malaria. METHODS: Each artemether compound tablet contains 120 mg benflumetolum and 20 mg artemether. 132 patients with vivax malaria were divided into 3 groups. Group A, 36 patients received 8 tablets as an initial dose, followed by 4 tablets daily for 2 days; group B, 41 patients received 8 tablets as an initial dose, followed by 3 tablets daily for 4 days; group C, 55 patients receiving chloroguine-primaquine served as control. Two patients of group A were voluntarily to be bitten by Anopheles dirus before and after medication to observe the influence of artemether compound on the sporogony. RESULTS: The average defervescence times for groups A, B and C were 22.3 h, 23.2 h and 25.0 h (P > 0.05), respectively, the average parasite clearance times were 33.5 h, 30.5 h and 44.9 h, respectively, the average parasite clearance times of groups A and B were all significantly shorter than that of group C (P < 0.01). The replase rates of groups A, B and C were 84.9%, 78.8% and 22.9%, respectively, followed-up at nine months, the relapse rates of groups A and B were higher than that of group C(P < 0.01). CONCLUSION: Two regimens of artemether compound have the advantage of high efficacy against vivax malaria.

Adolescent↗
PubMed1999

[Clinical significance and changes of fibrillation potential amplitude following denervation of laryngeal muscles].

OBJECTIVE: To evaluate the value of clinical application of examination of fibrillation potential amplitude of laryngeal electromyogram. METHOD: Fifty-four patients (65 sides) with recurrent laryngeal nerve paralysis were examined and only the maximum fibrillation potential amplitudes were recorded in the posterior cricoarytenoid muscles and thyroarytenoid muscles. RESULT: There was no significant difference between sexes, ages and sides. The fibrillation potential amplitude was maximum at 3 to 4 months after denervation of the posterior cricoarytenoid muscle or at 5 to 6 months after denervation of the thyroarytenoid muscle and still remained at certain level for years in some patients. Significant difference was showed in complete and incomplete nerve injuries groups, but changes of amplitude with time in incomplete nerve injuries group were small. CONCLUSION: The changes of fibrillation potential amplitude might indicate that the changes from muscle denervation was still reversible and might be more accurate than traditional method of examination.

Adult↗
PubMed1999

[CT scanning analysis for maxillary sinus bony septum abnormalities and its clinical significance].

OBJECTIVE: To assess the extent and distribution of disease as well as associated anatomic abnormalities in patients with chronic sinusitis and nasal polyps. METHOD: Both axial and coronal CT scans of eight patients who failed medical therapy and functional endoscopic sinus surgery (FESS) were reviewed retrospectively. RESULT: Among them, five were found to have vertically aligned coronal bony septum, two were horizontal, one sagittal. Complete bony septum divided the maxillary sinus into two separate cavities in four patients, others had incomplete bony septum. Based upon the CT scan findings, patients suffered from these anatomic abnormalities received Galdwell-Luc procedures and pansinusectomy through mid-facial degloving approach respectively. All patients did well postoperatively and were symptom free for six months. CONCLUSION: The results showed that the CT scan can display the distribution and extent of residual disease, demonstrate anatomic abnormalities, and guide therapeutic intervention. The combination of axial with coronal CT scan can effectively determine the incidence of the maxillary sinus bony septum.

Adolescent↗
PubMed1999

[Study on GMA-DNA adducts in vivo].

OBJECTIVE: To investigate whether glycidly mechacrylate (GMA-DNA) adducts can be produced in various organs of rat in vivo. METHODS: Rats divided into 5 groups were orally administrated with mutagen, GMA 31.25, 62.5, 125, 250 mg/kg respectively for 14 days. DNA adducts produced in liver, kidney, white blood cells and testis had been analyzed by nuclease P1 mediated 32P-postlabelling method. RESULTS: Several GMA-DNA adducts were formed in various organs (in white blood cells, 4 types, liver and kidney, 3 types and testis 1 type). The amount of GMA-DNA adducts increased with GMA dosage within 0-125 mg/kg dosages, degree of the overall level of GMA-DNA adducts in various organs were kidney > liver > white blood cells > testis. N3-methacrylate-2-hdroxypropyl-deoxycytidine monophosphate was found in kidney, liver and white blood cells. CONCLUSIONS: GMA with electrophilic group could react with negatively charged centers on DNA and form GMA-DNA adducts.

Animals↗
PubMed1999

[Pharmacological study on asthma-relieving decoction (dingchuan tang) treating asthma].

Asthma-relieving decoction (Dingchuan tang) is a famous prescription of treating asthma, but its pharmacology has been not reported. This experiment showed that Asthma-relieving decoction (Dingchuan tang) can protect experimental asthma that blending of histamine and acetylcholine caused (P < 0.05 [symbol: see text] P < 0.01), can resist external trachea smooth muscle's contracting that histamine caused (P < 0.01), and can promote secretion of phenol red of rat's respiratory tract (P < 0.01). Results indicated that Asthma-relieving decoction (Dingchuan tang) has significant effect of relieving asthma and expelling phlegm.

Acetylcholine↗
PubMed1999

[Application study of yangkang biological fertilizer on Panax notoginseng cultivation].

Yangkang Biological Fertilizer was sprayed on Panax notoginseng. The result indicated that the yield and the surviving rate can be raised 25.2% and 15.2% respectively. The best spraying practice were: in the unfolding stage of leaves (April) and bloom stage (July), with Yangkang Biological Fertilizer plus water (1:400), at four times every stage.

Fertilizers↗
PubMed1999

[Analysis of the vestiges of farm chemicals for Panax notoginseng].

The vestiges of farm chemicals in Panax notoginseng plants and medicinal materials from main production areas in Wenshan District was analyzed in this study. The result showed that the samples from the places contained hexachloro-cyclohexane and DDT. And the vestiges of hexachloro-cyclohexane was about 0.016-0.101 mg/kg, that of DDT was about 0.15-0.143 mg/kg. The content of Cu, Zn, Pb, Cd was lower than national standard of P. R. C.

China↗
PubMed1999

Loss of anterior chamber-associated immune deviation during normal pregnancy in primates.

PURPOSE: We recently found that loss of anterior chamber-associated immune deviation was associated with normal pregnancy in rabbits. The purpose of this study is to further investigate whether the same events occurred in nonhuman primates. METHODS: Mid-pregnant cynomolgus monkeys were randomly selected. Bovine serum albumin (BSA) was inoculated in anterior chamber of eyes of nonpregnant and mid-pregnant monkeys that were subsequently immunized with BSA in adjuvant. Delayed-type hypersensitivity (DTH) was assessed by skin challenge. RESULTS: Non-pregnant monkeys of intracameral BSA proved able to acquire antigen-specific suppression of delayed-type hypersensitivity. By contrast, inoculation of BSA to anterior chamber of pregnant monkeys abolished the DTH-suppression effect. CONCLUSIONS: This is the first demonstration in primates that loss of anterior chamber-associated immune deviation occurred during normal pregnancy. The fluctuations of systemic hormone levels during normal pregnancy might influence local immunoregulation within the eye.

Animals↗
PubMed1999

[The role of spleen in induction and maintenance of anterior chamber-associated immune deviation in different species of animals].

PURPOSE: The importance of the spleen to the induction of anterior chamber-associated immune deviation (ACAID) in mice has been known for some time. Removal of the spleen within the first 4 days of injecting antigen into anterior chamber can abolish immune deviation and result in immunity. The purpose of this study is to explore the role of spleen in ACAID in other different species of animals. METHODS: After splenectomy and sham-splenectomy, bovine serum albumin (BSA) as a soluble antigen was inoculated into the anterior chamber (AC) of different animals (rat, rabbit and monkey) respectively. Recipient animals were immunized with BSA and complete Freund's adjuvant. Delayed-type hypersensitivity (DTH) was assessed by skin challenge. The maintenance time of deviant immune response was evaluated in the fixed interval. RESULTS: All the animals with receiving intraocular antigen inoculation, both in splenectomized group and in sham-splenectomized group, did not display DTH reaction. In addition, the maintenance time of immune deviation in both groups after AC inoculation of antigen was not significantly different. In contrast, all the animals without receiving intraocular antigen inoculation, both in splenectomized group and in sham-sple-nectomized group, displayed positive DTH reaction. CONCLUSIONS: The spleen may not play an important role in the induction and maintenance of ACAID in rat, rabbit and monkey. These data suggest that as the evolution progresses, the function of spleen may be replaced by other lymphatic organs.

Animals↗
PubMed1999

[3-channels data acquisition system based on single-chip-microcomputer used in the measurement of coronary sinus blood flow].

The coronary sinus blood flow can be figured out, which based on the principle of thermodilution, so long as gets the temperature of blood, indicator and mixture of blood and indicator respectively. This system is a smart slave module with single-chip-microcomputer. The structure and principles of hardware and the flow chart of software are described in detail.

Blood Volume Determination↗