Search PubMed⌕ Search

Biomedical subjects

Z Xu

Publications and source records attributed to Z Xu.

At least 379 records · Page 21Linked to original sources
PubMed1997

[Preliminary study on differentiation of syndromes during HDT -6 degrees bed rest with traditional chinese medicine].

Differentiation of syndromes during 21 d HDT -6 degrees bed rest was made in 15 healthy young men. The results indicated that the subjects showed mainly deficiency of kidney-Yin, deficiency of Yin and hyperactivity of Yang, insufficiency of spleen-Qi and blood stasis in various degrees during the bed rest. The syndromes were most serious on the 3rd day, and then deficiency of kidney and deficiency of Yin and hyperactivity of Yang became mild gradually but insufficiency of spleen-Qi and blood stasis remained the same. The pulse condition was normal through the bed rest period

Bed Rest↗
PubMed1997

[Experimental comparison of two coxsackievirus B3 variants in murine myocardial cells].

There is lack of direct evidence whether the myocarditis can be induced by CVB3o. The two coxsackievirus B3 variants were used to infected murine myocardial cells. The results showed that: (1) In culture medium of murine myocardial cells infected with two variants, it did not show much differences in titers at 12 and 24 hours between CVB3o and CVB3m. (2) The two variants could all induce the death of myocardium, but with the elapse of time, the cell death rate of CVB3m infected cells was much higher than CVB3o. (3) CVB3o could not block the myocardial cells from infection by CVB3m. It is concluded that myocardial cells can be infected by CVB3o, but the degree of infection is lower than CVB3m.

Animals↗
PubMed1997

[Purification of hemagglutinin of hemorrhagic fever with renal syndrome virus by high pressure liquid chromatography and analysis of immunogenicity].

The brains of suckling mice and suspension of Vero-E6 cells inoculated with Chen's strain of hemorrhagic fever with renal syndrome virus (HFRSV) were obtained and prepared into high titre hemagglutinin (HAN). The crude HAN was purified by high pressure liquid chromatography. The molecular weight of the purified HAN is 56600 and has higher titre of hemagglutinin activity. It has been proved that the purified HAN has homogeneous molecular weight and buoyant density through SDS-PAGE and sucrose gradient ultracenrifugation. Nine monoclonal antibodies (McAb) from varions HFRS virus have been used for analyzing the epitope of purified HAN by ELISA. It was demonstrated that the purified HAN has epitopes of hemagglutinin and neutralizing antigens. The Balb/C mice could be induce specific antibody against HFRSV by immunization with purified HAN. The titre of neutralization was 40 and titre of hemagglutinin inhibition was 64. Some problems concerning the HAN of HFRS virus were discussed.

Animals↗
PubMed1997

[Determination of R- and S-mephenytoin in human urine by gas chromatography].

The levels of R- and S-mephenytoin in human urine were determined by chiral capillary gas chromatography with nitrogen-phosphorus detector. The conditions of the chromatography and detection included a chiral capillary column (Chirasil-Val, 25 m x 0.25 mm i.d., Alltech), column temperature (T) 190 degrees C, injector T 220 degrees C, detector T 240 degrees C, and the flow-rates of 0.85, 3.5 and 120 mL/min for nitrogen, hydrogen and air respectively. Based on the above conditions, the satisfactory separation of R- and S-mephenytoin was gained, and other interference from urine sample was not found. The linear curves for both tested compounds ranged between 12.5 and 2500 microg/L, with a minimum detectable concentration of about 6 microg/L. Because of its simplicity, rapidity, sensitivity and accuracy, this method has been extensively used for testing metabolic ability of S-mephenytoin polymorphic oxidation in the Chinese populations and for the determination of the activity of hepatic drug-metabolizing enzyme CYP2C19 using mephenytoin S/R ratio of the urine samples of subjects as an indicator.

Anticonvulsants↗
PubMed1997

[Absorption spectra study for fullerene-doped in polystyrene film].

The absorption spectra of C60 and C70-doped in polystyrene film and in solution were studied. The experiment results showed that the positions of the absorption peaks for C60-doped in polystyrene film moved a little toward longer wavelength than in n-hexane, and regular solid material appeared while the ratio of C60-doped in the film increased; The absorption peaks for C70-doped in polystyrene film were almost in consistent with that in solution. We suggest that C60 molecules may be connected as "microcrystalline" in polystyrene film, while C70 may be exist as single molecule or particle less than C60 in it. The preliminary model for the growth of "microcrystslline" in polystyrene film has been proposed.

English Abstract↗
PubMed1997

[The study of interactions of [CpFe(Co)2]2 with surface of alumina and Titania supports by Fourier transform diffuse reflection and photoacoustic infrared spectroscopy].

The diffuse reflection and photoacoustic infrared spectra of the species derived from dicarbonyl (eta5-cyclopentadienyl)iron (0) {[CpFe(CO)2]2 (Cp = eta5-C5H5)} which are supported on the surfaces of acidic,neutral and basic alumina (Al2O3) and Titania (TiO2) have been measured. The structures, stabilities and concentrations of these supported organometallic species depend markedly on the acid-base properties of the alumina surfaces. There is mainly species of [CpFe(CO)2Fe-H-Fe(CO)2Cp]+ on the surface of [CpFe (CO)2]2/Al2O3 (acidic) (A). The species of CpFe(CO)2(-O-) and [CpFe(CO)]4 are observed on the surface of [CpFe(CO)2]2/Al2O3(neutral)(B). On the suface of [CpFe(CO)2]2/Al2O3 (basic) (C), the mainly species is [CpFe(CO)2]4 with a few CpFe(CO)2(-O-) species. The concentration of species is highest on the surface of A and lowest on the, surface of C. The diffuse reflection and photoacoustic (middle and near )infrared spectra of [CpFe(CO)2]2/TiO2(T) show that the [CpFe(CO)2]2 absorbed on the surface of TiO2 is stable in the air at the room temperature. There is no a species derived from [CpFe(CO)2]2 to be observed. The diffuse reflection near infrared spectra of [CpFe(CO)2]2(D) and [CpFe(CO)2]2/TiO2 (T) are measured. Most of them are assigned to overtone and combination of carbonyl vibrations and several peaks are assigned to triple overtone and triple combination. The diffuse reflection infrared spectroscopy is the good method to study the interaction of organometallic compounds with metal oxide powder.

English Abstract↗
PubMed1997

[Molfig, a software for displaying the structure and vibration of molecule].

A Molfig software has been developed for displaying the structure and vibrational mode of molecule in our lab. Various functions and a friendly interface are equipped in the software. The testing results showed that the software may enhance our understanding of the relationship between the vibrational behavior and the structure of molecules.

English Abstract↗
PubMed1997

[Fluorescence and FT-IR spectroscopic studies on the mixed solid complexes of europium and terbium phthalate].

In this investigation, the fluorescence and FT-IR spectroscopic studies on synthesized Eu-Tb phthalate complexes and mixed solid complexes of europium and terbium phthalates were perfomed. The experimental results of the emission spectra excited by 365nm UV-light showed that the emission peak positions of Eu ( III ) [or Tb ( III )] wer shifted slightly due to the interaction between Tb ( III )and Eu ( III ) ions. However, the fluorescence intensities of one rare eath ion Eu ( III ) [or Tb (III )] were strongly influenced by the other. FT-IR spectra indicated that the coordination structures of carboxyl groups, both in mechanically mixed and synthesized solid complexes, were also changed. These results suggested that there are interactions between Eu ( III ) and Tb ( III ) ions in their mixed complexes.

English Abstract↗
PubMed1997

[Potential energy function of internal rotation for the molecules of (CX3)2Y type].

Studing on the molecules having M -tops of N -fold symmetries, decoupling the equation of motion for rotation and using the perturbation theory without wave function, the formula of the energies of internal rotation has been derived and the potential energy functions of internal rotation for (CH3)2O and (CF3)2CO have been determined.

English Abstract↗
PubMed1997

[Curvefit, an overlapping bands resolving software for IR spectra].

A Curvefit software has been developed for resolving the overlapping band of the vibartional spectra in our lab . Various functions and a friendly interface are equipped in the software. The testing results showed that both the speed of the calculation and the reliability of the final results are satisfactory.

English Abstract↗
PubMed1997

[Tissue and body fluid distribution of antibacterial agents in pregnant and lactating women].

OBJECTIVE: To determine the placental transfer and milk excretion of antibacterial agents. METHODS: A prospective study was conducted in pregnant and lactating women. The concentrations of 13 agents in tissue and body fluid were determined by bioassay or high performance liquid chromatography method. RESULTS: The results showed that metronidazole, ofloxacin, chloramphenicol, gentamicin and ampicillin crossed blood-placental barrier well, the ratio of fetal tissue or amniotic fluid/maternal serum drug concentration was higher than those of the other agents. The penetration of penicillins (except ampicillin) and cephalosporins was poor, but the drug concentrations were still reached therapeutic levels in the most tissues and body fluids. The placental transfer of amikacin, clindamycin and erythromycin was slightly higher than beta-lactams. The drug concentrations in breast milk was low, except metronidazole and erythromycin, the breast milk levels of the two drugs were more than 100% of maternal serum levels. CONCLUSION: Based on the results of the study and the consideration of possible adverse effects which may affect both the mother and the developing fetus as well as antibacterial activities of the drugs, the indications and reasonable use of the agents in pregnant and lactating period were recommended.

Anti-Bacterial Agents↗
PubMed1997

[Chronic diabetic complications and treatments in Chinese diabetic patients].

OBJECTIVE: To investigate the prevalence of diabetes complications and the control of blood glucose, lipids and treatments in Chinese diabetic patients. METHODS: In 1994-1996, 626 Chinese diabetics were investigated for their diabetic complications, the control of blood glucose, lipids and their treatments by a multi-disciplinary team which included diabetic specialists, ophthalmologists, neurologists, nephrologists, dieticians, cardiologists, and others. RESULTS: Of these patients, 49.6% had hypertension, 46.5% neuropathy, 37.0% retinopathy, 25.4% ischemic heart disease (including 2.3% with myocardial infarction), 22.8% proteinuria (including microalbuminuria), 12.3% cerebral infarction and 1.0% amputation. 16% had preproliferative and proliferative retinopathy, and 10.5% maculopathy. 28 patients (44 eyes) were blind, but only 29% of them were checked by ophthalmologists before this screening. 36% of these patients with antihypertensive agents had their blood pressure controlled. 60% patients with hypertension were not taking any antihypertensive agent, one-third hypertensive patients had their blood pressure uncontrolled even if they had been treated with antihypertensive agents. Hyperglycemia was controlled unsatisfactorily in half of the patients. Over one-fourth of the patients had severe hyperglycemia. 24%, 48% and 59% of the patients had hypercholesterolemia, hypertriglyceridemia and low HDL level respectively. 21.9% kept on diabetic diet and about one-fourth had their diet uncontrolled, including 14% who had never controlled their diet even if their hyperglycemia was severe and 20% newly diagnosed diabetic patients untreated. One hundred twenty-seven newly diagnosed patients with duration less than 1 month were investigated for their diabetic complications. 19.6%, 17.8% and 42.5% of them had retinopathy, proteinuria and neuropathy. Eight patients had preproliferative and 1 had proliferative retinopathy. Three patients (5 eyes) had maculopathy. 33% of these newly diagnosed patients had hypertension, 7 severe hypertension, including 3 patients with antihypertensive therapy. CONCLUSIONS: Diabetes was found late in the Chinese patients and diabetic complications had occurred in some patients by the time the disease was diagnosed. Hypertension was common in the Chinese diabetics. Over half of the diabetics had their blood glucose and blood pressure uncontrolled. Most of the diabetic patients had not controlled their diet. Macrovascular diseases and abnormal lipids metabolism were common. The risks of diabetic complications such as smoking, obesity and hypertension were not controlled and the awareness of these risks was low in the Chinese diabetics.

Adolescent↗
PubMed1997

[The development and efficacy tests for the autoclave indicator tape].

The paper describes the development and efficacy teats for the autoclave indicator tape which has specially effects on temperature of pressure steam, time of persistence and air of remainder in the autoclave, and quick, simple and advanced charater for indirectly testing the quality of autoclave sterilization.

Indicators and Reagents↗
PubMed1997

Multicenter clinical trial of thrombolytic therapy in 1,406 patients with acute myocardial infarction. Collaborative Group of Clinical Trial for Urokinase Therapy.

OBJECTIVE: To investigate the clinical efficacy and safety of intravenous thrombolytic therapy of Urokinase Tech-Pool (UKTP) in acute myocardial infarction (AMI). METHODS: The data were collected from the 148 participating hospitals from November, 1994 to April, 1996. A total of 1,406 patients with AMI were analyzed to evaluate the clinical efficacy, side effects and mortality of UKTP. The patency of the infarct-related artery (IRA) was evaluated in 124 patients by coronary artery angiography (CAG) 90 minutes after the onset of UKTP infusion. RESULTS: The reperfusion rate in IRA was 73.5% by clinical standards. The patency rate was 72.6% by CAG. The total mortality during the first 5 weeks was 7.8% (109/1,406). The rate of minor bleeding was 10.2% (143/1,406), of major bleeding 0.43% (6/1,406) and of intracranial hemorrhage 0.50% (7/1,406). In elderly patients (> 75 years old), UKTP was as effective and safe as in younger patients (< 65 years old). Late thrombolytic therapy with UKTP (> 6 hours after the onset of symptom) was still effective. The appropriate dosage of UKTP might be 150 million units of infusion within 30 minutes. CONCLUSION: UKTP is an effective, reliable and safe agent in the thrombolytic therapy of AMI.

Aged↗
PubMed1996

Effects of calcium-BAPTA buffers and the calmodulin antagonist W-7 on mouse egg activation.

Results of numerous experiments indicate that the transient rise in intracellular Ca2+ following sperm-egg fusion is essential for the subsequent events that constitute egg activation. Some events of egg activation, e.g., cortical granule exocytosis, however, appear more sensitive to intracellular Ca2+ than other events, e.g., cell cycle resumption. To examine if specific events of egg activation have different thresholds for Ca2+, we manipulated buffered intracellular Ca2+ concentrations by microinjecting Ca2+-BAPTA buffers and then examined the effect on the cortical granule exocytosis, recruitment of maternal mRNAs, and cell cycle resumption. We find that whereas cortical granule exocytosis occurs over a narrow threshold range of injected free Ca2+ concentrations between 0.5 and 1.0 microM, recruitment of maternal mRNAs is only partially stimulated at injected free Ca2+ concentrations of 2.5 microM, and no evidence for cell cycle resumption was observed (up to 2.5 microM Ca2+). Although the Ca2+- and phospholipid-dependent protein kinase, protein kinase C, is implicated in aspects of egg activation, calmodulin is also a potential target for the transient increase in Ca2+ that occurs following fertilization. Whereas incubation of eggs in the presence of the calmodulin antagonist W-7 followed by insemination does not block cortical granule exocytosis, cell cycle resumption, as assessed by the metaphase-to-anaphase transition, a decrease in histone H1 kinase activity and the time course for the emission of the second polar body are significantly delayed/inhibited.

Animals↗