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S Zhao

Publications and source records attributed to S Zhao.

At least 361 records · Page 20Linked to original sources
PubMed1997

[A non-invasive method for detecting endothelium-dependent dilation].

Using high resolution ultrasound, we measured the diameter of brachial arteries at rest, during reactive hyperemia and after glyceryl trinitrate (GTN) taking in 22 healthy persons. The results showed that brachial artery dilation was present both in reactive hyperemia and response to GTN. The mean flow-mediated dilation was 13.8 +/- 3.9% increment. The mean increment of dilation in response to GTN was 24.9 +/- 9.7%. The diameters of brachial arteries during reactive hyperemia and after sublingual GTN had significant difference compared with that in baseline (P < 0.01). It indicates that increased flow may mediate endothelium-dependent vessel dilatation and GTN cause endothelium-independent vessel dilatation in normal subjects. This paper presents a new non-invasive method of detecting endothelium-dependent dilation, which is proved to be simple, secure and practical.

Adult↗
PubMed1997

[Preiliminary studies on the efficacy and mechanism of interleukin-3 in the treatment of myelosuppression in mice].

The effects of recombinant interleukin -3 (IL-3) on the myelosuppression induced by irradiation and cyclophosphamide (CY) were observed in mice. The experimental results were as follows: (1) Intraperitoneal (i.p.) or subcutaneous (s.c.) injections of rh IL-3 daily for 5 days immediately after irradiation could alleviate the radiation-induced hematopoietic injuries. The yields and the numbers of CFU-E, BFU-E, CFU-Mix and CFU-GM in femural marrow in mice on the 9th day post exposure to 7 Gy gamma-rays were much higher than those in control animals. Meanwhile, rh IL-3 showed a weak influence on the numbers of bone marrow nucleated cells (BMC) and endogeneous CFU-S. (2) Subcutaneous administration of rh IL-3 for 5 consecutive days brought a favour of CY treated mice to elevate the yields of hematopoietic progenitor cells. (3) The effects of rh IL-3 on myelosuppression induced by radiation or CY were closely related to the route of administration, administration schedules, dosage of this cytokine and the disease state as well. So it seemed important to research still further an appropriate, optimal and flexible guide for clinical use. (4) In vitro rh IL-3 had no effect on the growth of murine BMC and CFU-GM. In comparison with control, after coculture with rmIL-3 (recombinant mouse interleukin (3)) BMCs of normal mice and mice irradiated with 2 Gy gamma-rays proliferated more rapidly and the yield of CFU-GM in them were higher. (5) The mechanism of the effects of rh IL-3 in marrow hypoplastic mice might be related to the indirect promoting influences on the proliferation and/or differentiation of the radiation damaged hematopoietic progenitor cells and/or hematopoietic stem cells.

Animals↗
PubMed1997

[The role of opioid receptors of arcuate nucleus in cytokine-induced hyperthermia].

The present study is to define the role played by the opioid receptors of ARH in the regulation of body temperature. 1 microliter of IL-1 beta (as pyrogen) was injected into the ARH of male Sprague-Dawley rat with an automatic micromanipulator to induce hyperthermia. 30 minutes prior to the injection of pyrogen, the experimental groups were pre-treated with general opioid receptor antagonist naloxone (Nal), selective mu, delta, kappa receptor antagonists CTAP, NTI, nor-BNI respectively. Controls were pre-treated with saline. The results showed that IL-1 beta-induced hyperthermia was blocked by Nal and CTAP, suggesting the involvement of, or mediation by, ARH opioid receptors (mainly the mu type) in IL-1 beta-induced hyperthermia. The blockade by delta and kappa antagonists was not remarkable. Thus their participation in this process is less likely. The similarity between the roles of opioid receptors of ARH and POAH in IL-1 beta-induced hyperthermia strongly supports the view that ARH may be an important component of the thermoregulatory center.

Animals↗
PubMed1997

[Prophylactic effects of magnesium sulfate and ligustrazin on the hypoxic-ischemic brain damage in neonatal rats].

OBJECTIVE: A model in neonatal rats was established to study pathophysiology of perinatal hypoxic-ischemic brain damage. METHODS: 7-9 day old Wistar rats were subjected to unilateral carotied artery ligation followed by hypoxic state for 3 hours (10% O2 + 90% N2, at 37 degrees C). Magnesium sulfate (0.5 mg/gBW) and ligustrazin (0.1 mg/gBW) was separately given a 30 min before hypoxia. Superoxide dismutase (SOD) and malonic dialdehyde (MDA) in the cerebral cortex and serum MDA were measured immediately after hypoxia. Neuropathologic examination was made in 4 weeks after hypoxia. RESULTS: It was found that SOD and MDA in the cerebral cortex and serum MDA in the hypoxicischemic group were significantly increased in comparision with the normal control group (P < 0.01), and that all these parameters either in the magnesium sulfate group or in the ligustrazin group were lower than in the hypoxic-ischemic group (P < 0.05). The hypoxic-ischemic group showed that there were neuronal degenerations in the gray matter, hippocampus and cerebellum which were reduced in the two treatment groups. CONCLUSION: Our results indicate that oxide free radical formation is one of the pathogenic factors of perinatal hypoxic-ischemic brain damage and magnesium sulfate and ligustrazin reduce hypoxicischemic brain damage due to indirect anti-oxidation.

Animals↗
PubMed1997

[The vascular basis of pedicled adrenal transposition and its usage in the treatment of Cushing's disease].

To treat Cushing's disease, we studied the length and exterior diameter of the inferior phrenic and superior adrenal artery and vein, and the reflow of the adrenal vein. The length and exterior diameter of those blood vessels were divided and measured by veiner calipor. Six patients with Cushing's disease were treated by pedicled adrenal transposition to the musculus of the back. The right inferior phrenic artery was 75-110 mm from the exterior edge of the vena cava to the distant branch of the superior adrenal artery, while the left inferior phrenic artery was 70-90 mm from the left edge of the aorta to the distant branch of the superior adrenal artery, both of which have veins to accompany them. The superior adrenal artery came from the inferior phrenic artery relatively common and was divided into six branches. The exterior diameter of the distal superior adrenal artery was 1.5-2.5 mm and could be freed for 40-80 mm. Lateral veins could complete the adrenal blood drainage after the left central adrenal vein was ligated. The transpositioned blood vessel pedicle consisted of the distant inferior phrenic artery and vein, the distant branches of the superior adrenal artery and vein. The patient who had received the transposition treatment had neither hypocortisolism nor recurrence after 4 to 35 months. The length of the inferior phrenic, superior adrenal gland vessels could content the remained adrenal gland to reach their transposition bed when freed. The pedicled adrenal transposition to the musculi is an ideal method in the treatment of Cushing's disease.

Adrenal Glands↗
PubMed1997

[Facial nerve protection during surgery for congenital malformation of the external and middle ear (review of 519 cases)].

The prevention of facial nerve injury in otoplasty for ear malformation is important. This paper analysed 519 cases of ear malformation collected during 10 years from 1985 to 1995. The hearing of 428 cases was improved, of which the hearing of 221 cases did recover to available level. A long-term follow-up of 198 cases showed that 152 cases had kept the same hearing level as that immediately after surgery. In 130 cases with single middle ear malformation the malformation rate of facial nerve was 60.8%(79/130), and that for chorda tympani 5.4% (7/130). In 75 cases of middle ear malformation with stricture of external acoustic meatus the malformation rate of facial nerve was 60.0% (45/75), and that for chorda tympani 13.3%(10/75). In 314 cases of middle ear malformation with atresia of external acoustic meatus the malformation rate of facial nerve was 42.5%(142/314), and that for chorda tympani nerve 100.0%(314/314). Two cases(0.4%) were of surgical facial nerve paralysis. For protection of facial nerve, it was important to master the anatomy of temporal bone and have a high-resolution computed tomographic scanning to identify facial nerve. It was also important to use electroneurographic monitoring when necessary.

Adolescent↗
PubMed1997

[Pharmacokinetics of Caulis Erycibes injection in rabbits].

The pharmacokinetics of single i.m. doses of Caulis Erycibes injection in ten rabbits was studied. The concentration of scopoletin-one of the effective components in Caulis Erycibes injection in serum was analyzed by high performance liquid chromotography with fluorescence monitor. In eight of ten rabbits a second peak was found on the serum concentration-time curve. The absorption of scopoletin was quick with Tmax 1 = 8.08 +/- 3.88 min, Cmax 1 = 145.45 +/- 47.65 ng/ml. The time to the second peak concentration (Tmax 2) was 2.45 +/- 1.79 h, Cmax 2 = 48.66 +/- 41.66 ng/ml. The other parameters were as follows: Ke = 0.56 +/- 0.37 h-1, T1/2 = 1.81 +/- 1.14 h, MRT = 156.61 +/- 98.41, CL/F = 220.54 +/- 109.35 ml/min, Vd/F = 30.49 +/- 19.34 L, AUC = 8.52 +/- 5.15 micrograms.min/ml. The reason for the appearance of double peaks was discussed.

Animals↗
PubMed1997

[Determination of flavonoids in the leaves of Hippophae L. by HPLC].

A method for determination of three flavonoids in the leaves of Hippophae by high presure liquid chromatography was established. The contents of these flavonoids in the leaves of seven different species of Hippophae were determined and compared. The results provide a scientific basis for evaluating and utilizing the leaves of Hppophae.

Chromatography, High Pressure Liquid↗
PubMed1997

[Effects of HE particles on medicinal plant Agastache rugosus (Fisch. et Mey.) O. Ktze].

The biological effect of HE particles on the seeds of Agastache rugosus was probed in experiments on board a retrievable satellite. The result shows that the germination rate of the seeds pierced by HE particles radiation appears rather low. The seeds hit by HE particles (piercing radiation or not) start to germinate two days earlier than those in the control group, and the first leaf emerges four to five days earlier than that in the control group. The resultant seedlings grow markedly faster. Variations take place in the nuclear types of chromosome. The yield of essential oils becomes slightly higher. No marked changes have been observed in the major chemical components of these oils.

Chromosomes↗
PubMed1997

[Determination of aniline derivatives in waste water with reversed-phase high performance liquid chromatography].

A reversed-phase high performance liquid chromatographic method for the determination of aniline derivatives in waste-water is described. Chromatographic conditions were: column, Hypersil BDS (200 mm x 4.0 mm i.d., 5 microm); mobile phase, methanol-water, gradient elution; flow rate, 1.0 mL/min; detection wavelength, 254 nm. Quantification was carried out based on the external standard of aniline derivatives. The pH of waste water sample was adjusted to 11-12 with dilute NaOH solution prior to extraction with CH2Cl2. The extractives concentrated in K-D concentrator and filtered with FH 0.5 microm membrane. Finally make up the volume to 1 mL and test it with reversed-phase high performance liquid chromatography. The linearity range of calibration curve used was 0.005-0.3 microg. The minimum detectable quantities of aniline derivatives varied from 1.20 ng to 3.00 ng. The average recoveries were from 51.57% to 107.92%, and the RSDs of the method were from 1.88% to 5.98%. The method is simple, rapid, and accurate.

Aniline Compounds↗
PubMed1997

[Separation of flavonol isomers by packed column supercritical fluids chromatography].

Flavonol isomers, which differ only in the position of hydroxyl group substitute on their chemical structures, showed different chromatographic behaviors. These polar compounds, in general, can be analyzed by high performance liquid chromatography. In this paper, the separation of flavonol isomers by home-set up packed column supercritical fluid chromatograph with carbon dioxide modified by ethanol containing 0.5% (V/V) phosphoric acid as mobile phase is described. The effects of temperature, pressure, composition of mobile phase and packed column type on the separation were studid. The addition of phosphoric acid to the mobile phase, which can not result in corrosion on the chromatographic system, enabled flavonol to elute from the column, and showed that the composition of the mobile phase was the most pronounced factor influencing the separation. Three columns were evaluated for the separation. It showed that the phenyl-bonded silica column was the best and the ODS column was the worst for the isomers separation. Increasing pressure shortened the retention time of each compound with good resolution, and higher temperature led to longer retention time.

Chromatography, Supercritical Fluid↗
PubMed1997

[Spectral study on the self-polymerizing reaction of N-diisopropyl phosphoryl amino acids].

By using polarization sensitive CARS method, five kinds of N-diisopropyl phosphoryl-alpha-amino acids are investigated. They polymerize themselves to form peptide at 55 degrees C for 40 hours. The vibration mode spectra prior and after the reaction are recorded. With the help of theoretical calculation, the configuration of these peptides are inferred to be trans form and the specificities vibration modes are assigned.

Amino Acids↗
PubMed1997

CD30-ligand and CD40-ligand expression in lymph nodes involved with Hodgkin's disease.

BACKGROUND: Reed-Sternberg cells of Hodgkin's disease express CD30 and CD40 receptors. The ligands for these receptors have been reported to have pleiotropic biologic activities in vitro, including induction of cell death and enhancing cell survival. Co-expression of the ligands for these receptors in lymph nodes involved with Hodgkin's disease is not known. PURPOSE: The purpose of this study was to examine CD30 ligand (L) and CD40L expression in lymph nodes of patients with Hodgkin's disease, and to study CD30L expression on nodal lymphocyte subsets. MATERIALS AND METHODS: CD30L expression on subsets of lymphocytes of five lymph nodes involved with Hodgkin's disease was determined by two-color FACScan. Messenger RNA expression of CD30L and CD40L was determined by the reverse-transcriptase polymerase chain reaction (RT-PCR) method performed on seven specimens involved with Hodgkin's disease (five lymph nodes and two spleens). RESULTS: Four of seven specimens (57%) contained cells that expressed CD30L mRNA and three specimens (43%) contained CD40L-expressing cells. The mean percentage of nodal lymphocytes expressing CD30L surface protein was < or = 20%. CONCLUSION: Hodgkin's disease lymph nodes and spleens frequently lack CD30L- and CD40L-expressing cells, and when CD30L is expressed, it is usually detected on few numbers of lymphocytes. The balance in the level of expression of these ligands in Hodgkin's disease lymph nodes may be related to the disease's clinical behavior.

CD40 Antigens↗
PubMed1997

Alterations in thromboxane synthase and thromboxane A2 receptors in experimental alcoholic liver disease.

We have previously shown that hepatic thromboxane production is increased in experimental alcoholic liver disease. The present study was designed to investigate the cell type in liver responsible for increased thromboxane synthesis and the role of the thromboxane receptor system in the pathogenesis of liver injury. Male Wistar rats were divided into four groups and fed a liquid diet with dextrose or ethanol for 2, 4 and 8 weeks. Medium chain triglycerides or corn oil provided the dietary fatty acids. Kupffer cells, endothelial cells and hepatocytes were isolated from rats fed the different diets for 4 weeks. Liver histopathology, thromboxane synthase mRNA and protein, thromboxane levels and thromboxane receptor mRNA were evaluated in each group. In rats fed corn oil and ethanol, an increase in thromboxane synthase and liver levels of thromboxane metabolites were significantly higher than in the corn oil-dextrose-fed group and were correlated with the presence of pathological changes in the liver. Kupffer cells showed increased expression of thromboxane synthase. In rats fed medium chain triglycerides and ethanol, the levels of thromboxane synthase mRNA and protein were significantly lower than in the corn oil-ethanol-fed groups (P < .01) and liver injury was absent. However, the levels of thromboxane synthase mRNA, protein and thromboxane were significantly higher in the medium chain triglyceride-ethanol-fed rats than in the respective dextrose-fed controls. Among the different cell types, thromboxane A2-receptor mRNA levels were highest in the Kupffer cells in corn oil-ethanol-fed rats. The increase in thromboxane synthase in Kupffer cells together with an increase in thromboxane receptor levels suggests than thromboxanes may contribute to liver injury in ethanol-fed rats.

Animals↗
PubMed1997

High responsiveness of cytosolic free calcium concentration to angiotensin II in cultured pulmonary arterial myocytes from pulmonary hypertensive rats.

Pulmonary arterial myocytes were cultured from normotensive and pulmonary hypertensive rats. Microfluorimetry of Ca2+ signals in fluo-3-loaded single myocytes at day 7 of culture was performed by a laser-scanned confocal imaging system. The resting level of cytoplasmic Ca2+ concentration ([Ca2+]i) in vascular myocytes obtained from hypertensive rats was higher than that in cultured myocytes obtained from normotensive rats. Angiotensin II elevated [Ca2+]i in the vascular myocytes cultured from both normotensive and hypertensive rats. However, a rise of [Ca2+]i induced by angiotensin II in the vascular myocytes obtained from pulmonary hypertensive rats was higher than that obtained from normotensive rats. On the other hand, the response of [Ca2+]i to A23187 did not differ between the vascular myocytes cultured from normotensive and hypertensive rats. The present results suggest that the resting and angiotensin II-responsive levels of [Ca2+]i in pulmonary arterial myocytes cultured from pulmonary hypertensive rats are higher than those cultured from normotensive rats.

Angiotensin II↗