Search PubMed⌕ Search

Biomedical subjects

Z Yang

Publications and source records attributed to Z Yang.

At least 919 records · Page 51Linked to original sources
PubMed1990

[Influence of finger pressing massage on cAMP and cGMP in the cerebrospinal fluid in prolapsed intervertebral disc].

This paper used RIA method to observe 11 cases of prolapsed intervertebral disc patients, detect the change of cAMP and cGMP in the cerebrospinal fluid before and after finger pressing massage in acupuncture point Weizhong and Chengshan in order to discuss the mechanism of analgesia of finger pressing massage. The results showed that the pain was relieved after finger pressing massage. cAMP of the cerebrospinal fluid increased from 0.51 +/- 0.19 to 0.63 +/- 0.13 pm/ml, in average 32% higher than that before the therapy (P less than 0.05). Since cGMP decreased from 30.52 +/- 26.42 to 23.20 +/- 16.91 pm/ml, it showed that the mechanism of analgesia of finger pressing massage might be due to the fact that the therapy excited selectively endogenous analgesia system, caused the increase of endorphin releasing, and was accompanied by the regulation of cAMP and cGMP.

Acupuncture Points↗
PubMed1990

[Study on identification for the motility and flagella antigen of four international reference strains of Escherichia coli].

Authors identified four strains of Escherichia coli from Collaborative Centre for reference and research on Escherichia coli-Klebsiella (WHO) in Denmark. Our results were different from original record and reference. It was shown that strain H311b and H5 were motile strains, and its H antigen respectively is H11 and H27. The strain W27 is nonmotile. H antigen of the strain H511 is H40, not H8. Antigen formula of four strains respectively is 26:60:11 (strain H311b), 81:97:27 (strain H5), 115:-:- (strain W27), 102:-:40 (strain H511).

Antigens, Bacterial↗
PubMed1990

[A new serotype of Shigella boydii].

Two strains which belong to the same serotype of Shigella were isolated from the bloody-pus stool of two patients (in 1986) and is reported in this paper. The results were identical both showing agglutination in low titer with serotype 8 of S. dysenteriae and serotype 4 of S. boydii when the two strains were checked well with all kinds of diagnostic antisera and vice versa, ie the antisera produced by the two strains were also checked well with sera prepared with the representative strains of all Shigella spp. No cross agglutination with O6, O7, and O150 of E. coli were found. Consequently, It appears to be a new serotype of Shigella. These two strains possess the ability of causing keratitis in guinea-pigs as well as invading epithelial cells, the DNA of both strains in agarose-electrophoresis showed a large plasmid, indicating that they are virulent strains possessing invasive ability. It was concluded that these two strains belonged to Shigella boydii as they fermented mannitol and non-related antigenically with Shigella flexneri. Since serotype 1-18 of S. boydii have been reported recently, we propose that this new serotype should be serotype 19 of Shigella boydii.

Animals↗
PubMed1990

[Ultrastructural localization of Leishmania donovani antigen by immunogold labeling technique].

By using Lowicryl K4M, a kind of low temperature embedding resin, to embed promastigotes of Leishmania donovani at -30 degrees C, the protozoal structure was well preserved when visualized by electron microscope. We have determined the distribution of the promastigote antigen of human and canine isolates of Leishmania donovani from Sichuan using two monoclonal antibodies combined with biotinylated goat antimouse IgG and streptavidin/colloidal gold conjugates. The results showed that the antigen recognized by the protective monoclonal antibody 2H6-E3 was mainly distributed in the outer side of promastigote membrane of Leishmania donovani Sichuan canine isolate. According to the high density of localized gold particles this antigen might be abundant in the promastigote membrane. This result facilitates further research on the component, property and function of this antigen. Monoclonal antibody 1H7-C2-E7 recognized the promastigote antigen of both human and canine isolates of Leishmania donovani from Sichuan, suggesting that these two isolates might share a common antigen, and 1H7-C2-E7 antibody might be used to diagnose the leishmaniasis caused by these two isolates.

Animals↗
PubMed1990

[Determination of traces of gallium in air by oscillographic polarography].

Gallium and its compounds in air collected by millipore filter membrane are leached by 10% HNO3 at room temperature. After being adjusted with ammonia solution to pH8-9, the leachate is filtered and the filtrate is evaporated to dryness on a water bath. The residue is dissolved with 2 ml of 10% HNO3 and then into the solution are added 0.5 ml of 5% hydroxylamine hydrochloride solution, 0.20 ml of 5% sulfosalicyclic acid solution, 0.5 ml of NaF solution (1mg F/ml) and 1 drop of methyl red solution. Let it stand for 5 min after the color of the solution turns orange by addition of 1:1 NH4OH solution. Add 0.20ml of 0.20% cupferron solution, 0.20ml of 0.5% diphenyl-guanidine solution (prepared in 95% ethanol) and 0.5ml of acetic acid-ammonium acetate buffer (pH 7.0). Then add water to make the final volume of the test solution to be 10ml and measure the height of the second derivative polarographic wave at -1.08V (vs.SCE). The sensitivity of the method is 0.005-0.10 microgram/ml, the coefficient of variation 6.8%, recovery 97.8%. Within 0.005-0.10 microgram/ml, the wave height is linear with the concentration of gallium.

Air↗
PubMed1990

[Application of ion chromatography to identification of anaerobic bacteria].

The fatty acids of anaerobic bacteria were detected by ion chromatography (IC). The results showed that 11 kinds of standard fatty acids could be analyzed within 15 min, and just needed 1 injection sample. The fatty acids patterns of 40 strains of anaerobic bacteria detected by IC were essentially the same as that by gas chromatography (GC) reported by VPI. In comparison with GC, IC has further advantages: pretreatment is simpler, both volatile and non-volatile fatty acids can be analyzed at the same time, and formic and lactic acid can be well analyzed.

Bacteria, Anaerobic↗
PubMed1990

Effect of three-year multidrug therapy in multibacillary leprosy patients.

The feasibility and effects of a 3-year treatment using rifampicin (RFP), clofazimine (B663) and dapsone (DDS) in multibacillary leprosy patients in Yangzhou Prefecture and Dongtai County (1983-1986) are reported. Among 591 active multibacillary leprosy patients in the two areas, 569 (96.30%) were treated with this regimen. Of 303 cases available for analysis, 196 (64.7%) cases showed negative skin smears and clinical inactivity. The rest showed different degrees of improvement. The average reduction of BI was 0.78. The intensity and frequency of ENL and neuritis decreased markedly with treatment. The main side-effects were pigmentation and ichthyosiform changes of the skin, but these did not influence treatment.

Adult↗
PubMed1990

[Effect of a new positive inotropic agent (OPC-8212) on intracellular potential of isolated canine ventricular papillary muscle].

This study adopted intracellular microelectrode technic to observe the effect of OPC-8212 (Vesnarinone) on intracellular potential of isolated canine ventricular papillary muscle. The record and data processing were completed by computerized intellective instrument designed by ourselves. The results of intracellular record in 14 canine ventricular papillary muscle showed no significant change in the resting potential (RP), amplitude of action potential (APA) and maximum depolarize velocity of 0 phase (Vmax). But significantly increased whole duration of action potential (APT). The duration of repolarization to 1/3 (APD 1/3) and to 2/3 (APD 2/3) significantly increased too. The plateau phase raised. These results suggest that K+ permeability at resting myocardiac cell membrane may have not been effected by OPC-8212. Activation of the fast sodium channel may have not been effected too. The results of our studies also suggest that inward flow of Ca2+ increased. The delayed outward K+ (Ik) and the inward, rectifying K+ current (Ik1) possible decreased. Thus, the OPC-8212 might become a nonglucoside and noncatecholamine new positive inotropic drug.

Action Potentials↗
PubMed1990

[The X-ray characteristic feature of the multiple primary malignant tumor of digestive tract].

A study on the multiple primary malignant tumor of digestive tract (MPMTDT) was made in the period of 1984-1988 in our hospital. Twenty five cases are reported in this paper. All of them were examined by X-ray, endoscopy, and proved to be MPMTDT by surgery and pathological examination. Twenty three cases were double primary tumors and 2 cases triple primary malignant tumors. The characteristic X-ray feature of the site of predilection and manifestation in primordial period of MPMTDT are described in this paper. These criteria are important for the early detection and selection of treatment of the tumors.

Adenocarcinoma↗
PubMed1989

A study of the monoclonal antibody OC 125 to diagnose malignant ovarian tumors.

Serum CA 125 was assayed preoperatively in 40 patients with ovarian malignancies and in 44 normal individuals. The correlation between CA 125 and tumor histology, tumor burden, ascites, and the clinical stage was analyzed. CA 125 levels greater than 65 U/ml were defined as positive. The results revealed normal values in each of the 44 normal individuals. CA 125 was elevated in 35 of 40 (87.5%) patients with malignant ovarian tumors including 23 of 24 (95.8%) patients with epithelial ovarian cancers, 7 of whom had stage I disease. Serum CA 125 was also elevated in 12 of 16 (75%) patients with nonepithelial ovarian malignancies. The results suggest that the CA 125 level can be correlated with tumor histology, tumor burden, and ascites but not with clinical stage.

Antibodies, Monoclonal↗
PubMed1989

Steady-state arterial and hepatic venous plasma concentrations of 5-bromo-2'-deoxyuridine and 5-iodo-2'-deoxyuridine in animals--drugs which are subject to both splanchnic and extra-splanchnic elimination.

We have previously shown that 5-fluorouracil (FUra) in humans obeys Michaelis-Menten elimination kinetics. In this article we show that the related bromine and iodine-containing analogs in animals obey similar kinetics. Steady-state arterial (CssA) and hepatic venous plasma (CssV) concentrations of 5-bromo-2'-deoxyuridine (BrdUrd) are reported for 7 rabbits given 5 different infusion rates of BrdUrd and 5 dogs given 4 or 5 different infusion rates of BrdUrd. Steady-state arterial and hepatic venous plasma concentrations of 5-iodo-2'-deoxyuridine (IdUrd) are reported for 5 rabbits and 2 dogs given 5 different infusion rates of IdUrd. Each set of data could be fitted by a nonlinear least squares method to the equation: (equation; see text) where Vm/Q is the maximum difference, (CssA) - (CssV), and Km is the Michaelis constant. The estimated parameter Vm/Q and Km are compared for the two drugs and different species and also with the same parameters derived in the same manner from previously published data on fluorouracil in 8 cancer patients. The infusion rate needed to saturate the splanchnic elimination system (Rs in mumol/kg/min) was also estimated. For BrdUrd the mean value of Rs in the rabbit, namely 1.23, and in the dog, namely 1.25 mumol/kg/min are essentially the same.

Animals↗
PubMed1989

[Transsphenoidal approach hypophysectomy for pituitary apoplexy].

Five cases of pituitary apoplexy were treated via transsphenoidal approach, this accounted for 17.8 percent of pituitary adenomas treated by surgery in our hospital. Crucial points for diagnosis were: (1) clinical signs and symptoms of pituitary adenomas, (2) sudden onset of headache or increasing headache accompanied by loss of vision. (3) An area of low-density with a high-density ring within the sella in CT scanning. Operation is the main measure to reduce the death rate while large doses of antibiotics and steroid hormones are also necessary.

Adult↗
PubMed1989

Endothelium-dependent regulatory mechanisms in human coronary bypass grafts: possible clinical implications.

The internal mammary artery and saphenous vein are used as grafts in patients undergoing coronary bypass surgery. Different biological properties of arterial and venous grafts might contribute to the better graft function, lower patient mortality and higher patency rate of the mammary artery. We investigated the role of endothelium-derived relaxing factor (EDRF), which is a vasodilator and inhibitor of platelet function, in arterial and venous grafts. In mammary arteries, acetylcholine, thrombin, adenosine diphosphate, histamine and the calcium ionophore A23187 evoked endothelium-dependent relaxations blocked by hemoglobin or methylene blue, but not by cyclooxygenase inhibitors delineating EDRF as the mediator; in vascular smooth muscle cells, this was associated with a rise in intracellular cyclic GMP. Exogenous nitric oxide evoked potent endothelium-independent relaxations. In the saphenous vein, endothelium-dependent relaxations to all agonists, except the calcium ionophore, were weak, indicating heterogenous endothelium-dependent vascular reactivity as compared to the artery. The mammary and saphenous vein exhibited an enhanced sensitivity to nitric oxide. The greater release of EDRF in the internal mammary artery, particularly in response to platelet derived products, could contribute to the higher patency rate of arterial as compared to venous grafts and give new insights into mechanisms involved in graft function and vascular occlusion in man.

Coronary Artery Bypass↗
PubMed1989

[Chemical constituents of Cordyceps mililaris (L.) Link].

Six constituents were isolated from the hypha of Jinlin Cordyceps mililaris. The structures were determined to be beta-sitosterol, ergosterol, D-mannitol, daenine adenosine and cordycepin (3'-deopadenosine). Cordycepin, ergosterol, adenine were isolated for the first time from this hypha of Jinlin C. mililaris.

Adenine↗
PubMed1989

Endothelium-dependent vascular responses: effect of hypertension and cyclosporin A.

Through the release of endothelium-derived relaxing and contracting factors, the endothelium can profoundly affect local vascular tone. In hypertension and during chronic cyclosporin A therapy, morphological changes of the endothelium develop. Recent studies in isolated arteries have demonstrated that endothelium-dependent relaxations induced by a variety of substances are decreased in acute and chronic hypertension and during cyclosporin A therapy. A reduced vascular smooth muscle responsiveness to endothelium-derived relaxing factor, the release of a cyclooxygenase-dependent endothelium-derived contracting factor in some animal models of hypertension, and possibly a decreased release of EDRF under some conditions may contribute to these functional alterations. In hypertension and during cyclosporin. A therapy, functional changes of the endothelium may contribute to increased peripheral vascular resistance and to vascular damage occurring under these conditions.

Animals↗
PubMed1988

[Endothelium-derived relaxing factor(s): endogenous nitrates in the circulation?].

Endothelial cells release a potent vasodilator which activates guanylate cyclase and thereby induces relaxation of vascular smooth muscle cells. The so-called endothelium-derived relaxing factor (EDRF) is released by acetylcholine, local and circulating hormones, and substances released from aggregating platelets or formed during activation of the coagulation cascade. Nitric oxide (NO) probably accounts for the factor's activity. Thus, endothelial cells produce endogenous nitrates causing vasodilatation and inhibition of platelet adhesion and aggregation. Under physiological conditions, EDRF may play a role in the prevention of vasospasm and thrombosis. On the other hand, the impairment of endothelial regulatory mechanisms in atherosclerosis and hypertension may be involved in the pathogenesis of vascular occlusion and thereby of myocardial infarction, stroke and peripheral vascular disease.

Acetylcholine↗
PubMed1988

Two distinct genetic loci regulating class II gene expression are defective in human mutant and patient cell lines.

Heterokaryons were prepared and analyzed shortly after cell fusion using two mutant class-II-negative human B cell lines (RJ 2.2.5 and 6.1.6) and a cell line (TF) from a patient with a class-II-negative Bare Lymphocyte Syndrome. The resulting transient heterokaryons were analyzed by using an anti-HLA-DR monoclonal antibody to assess the cell surface expression of HLA-DR (the major subtype of class II antigens) by immunofluorescence microscopy and by using uniformly 32P-labeled SP6 RNA probes in Northern blots and RNase protection assays to assess mRNA synthesis. We find that class II gene expression in a B cell line from a Bare Lymphocyte Syndrome patient (TF) is rescued by a B cell line which expresses class II antigens indicating that this disease, at least in part, is caused by a defect(s) in a genetic locus encoding a factor(s) necessary for class II gene expression. Secondly, reciprocal genetic complementation was demonstrated in the heterokaryons 6.1.6 x RJ 2.2.5 and TF x RJ 2.2.5 (but not in TF x 6.1.6) by detection of cell surface DR by immunofluorescence microscopy and by a novel class II mRNA typing technique which allows characterization of distinct class II alleles. Thus, the two mutants generated in vitro have defects at two different genetic loci encoding specific regulatory factors necessary for human class II gene expression. One of these mutant cell lines, but not the other, complements the defect in the patient cell line, TF.

B-Lymphocytes↗