Biomedical subjects

Y Ma

Publications and source records attributed to Y Ma.

At least 325 records · Page 18Linked to original sources

PubMed1998

[The relationship between hepatocellular carcinoma and hepatitis C virus infection in Guangxi, China].

OBJECTIVE: To study the significance of HCV infection as a risk factor for hepatocellular carcinoma (HCC) in Guangxi. METHODS: Monoclonal antibodies against the core, NS3 and NS4 region of HCV, and anti-HBsAg antibody were used for immunohistochemical staining. RESULTS: The frequency of HCV infection from regions with high, intermediate and low prevalence of HCC was 24/63(38.1%), 23/62 (37.1%) and 30/77(39.0%), respectively, while that of HBsAg was 84.1%, 83.8% and 84.4%, respectively. The overall positive rate of HCV infection was 77/202 (38.1%), and of HBV infection was 170/202 (84.2%). CONCLUSION: While HBV infection frequently accompanies HCC, HCV infection is present in more than 1/3 of HCC. This is generally the case regardless of geographical difference in HCC prevalence.

Antibodies, Monoclonal↗

PubMed1998

[Preliminary studies of apoptotic cell-associated antigens on hepatoma].

OBJECTIVE: To analyse antigens transiently expressed on hepatoma cells during apoptotic response. METHODS: Hepatoma HCC9204 cells were treated with 6% ethanol for 6 hr to induce apoptosis. Apoptotic HCC9204 cells were isolated and homogenized. After centrifugation at 14,000 rpm, the supernatant was dialyzed against water with molecular weight cutoff at 12,000. The dialysate was used as hepatoma apoptotic cell-associated antigen (HACAA). Subtractive immunization technique was used to prepare polyclonal antibodies against apoptotic cell-associated antigens on hepatoma. The antibody response to HACAA was determined by ELISA and immunoblot assays. Localization of HACAA on hepatoma apoptotic cells was demonstrated immunocytochemically. RESULTS: This polyclonal antibody reacted more strongly with HACAA than with antigen likewise prepared from non-apoptotic hepatoma cell. The antigenic determinants were sensitive to trypsin and mainly located on the cytoplasmic membrane. CONCLUSION: Epitopes are expressed on hepatoma apoptotic cells which can be used to examine an apoptotic response. The antibody reported in this paper is useful to screen novel apoptosis associated genes.

Antigens, Neoplasm↗

PubMed1998

[Dynamics of anti-HEV ORF2, ORF3, IgM and IgG in serial sera of patients with hepatitis E and their clinical significance].

OBJECTIVE: To study the dynamics of anti-HEV ORF2, ORF3, IgM and IgG in serial sera of patients with hepatitis E. METHODS: Anti-HEV was detected in serial sera of 52 patients, by an enzyme-linked immunosorbent assay (EIA) based on two synthetic peptides separated or combined from open reading frame (ORF) 2 and 3 of HEV genome. RESULTS: Both anti-ORF2 and anti-ORF3 in serum were at the highest levels in early acute phase of the disease, and declined gradually with the course, especially anti-ORF3. The sensitivity of the EIA using both ORF2 and ORF3 peptides was higher than that of either alone. The positive rates of anti-HEV IgM and anti-HEV IgG were separately 71.1% (32/45) and 97.8% (44/45) within 15 days after onset, then decreased more dramatically in IgM than in IgG with the course. CONCLUSION: Both ORF2 and ORF3 proteins should be used for the development of anti-HEV EIA kit. It seems to be more specific in anti-HEV IgM and more sensitive in anti-HEV IgG as a diagnostic marker of hepatitis E.

Adolescent↗

PubMed1998

[Endoscopic transnasal repair of congenital choanal atresia].

Two cases of congenital choanal atresia treated with endoscopic transnasal repairing were reported. Nasal endoscopy and axial CT scanning are important for establishing the diagnosis. Endoscopic plastic operation for choanal atresia is the best procedure. There are following advantages: short approach, clear field of vision, complete resection of atresia plate, well preservation of mucosa on the nasopharyngeal side of atresia plate, no side injury, less bleeding and higher success. The mucosa preserved completely on the nasopharyngeal side can totally cover the bare bony edges. The endoscopy after operation is important to remain nasal patency.

Adolescent↗

PubMed1998

[Changes of thyroid and adrenocortical functions after bone marrow transplantation with MAC conditioning regimen in leukemia patients].

OBJECTIVE: To investigate the effect of MAC conditioning regimen on endocrine glands function in leukemia patients after bone marrow transplantation(BMT). METHODS: Thyroid and adrenocortical functions were assayed by radioimmunoassay (RIA) in 26 leukemia patients before and after BMT. RESULTS: All patients had normal thyroid and adrenocortical functions before BMT. As compared with that pre BMT, the median serum TSH levels were increased at 1, 3 and 6 months post BMT(P < 0.01). This thyroid dysfunctions were found in 7 of 26 patients, 6 of whom were recovered at 6 months post BMT. CONCLUSION: There was little effect of MAC conditioning regimen on adrenocortical function. Thyroid dysfunctions were found in 28% of the patients after BMT, and normalized in a short period without replacement therapy.

Adolescent↗

PubMed1998

[Retinoic acid inducing Fas expression in HL-60 cells].

OBJECTIVE: To investigate the effect of all-trans retinoic acid (ATRA) and 9-cis retinoic acid (9-cis RA) on the expression of Fas and the sensitivity to anti-Fas induced apoptosis in HL-60 cells. METHODS: Fas expression was detected by flow cytometry. Anti-Fas induced apoptosis (AFIA) was determined by morphological features, DNA fragment electrophoresis, and flow cytometric cell cycle analysis. RESULTS: Fas antigen was weakly expressed on HL-60 cells. After incubation of HL-60 cells with 10(-6) mol/L ATRA or 9-cis RA for 4 days, both the Fas expression and AFIA were significantly enhanced. 9-cis RA was more potent than ATRA in increasing the sensitivity to AFIA. CONCLUSION: RA might upregulate Fas expression. Further elucidation of its molecular mechanisms might provide a rationale for new therapeutic strategies of malignant diseases.

Antineoplastic Agents↗

PubMed1998

[Influence of fry-processing on outward character and inner quality of volatile oil containing drugs such as fructus Viticis, etc].

According to the requirement of outward character in processing traditional Chinese drugs, five volatile oil containing drugs Fructus Viticis, Rhizoma Atractylodis Macrocephalae, Rhizoma Cyperi, Fructus Foeniculi and Fructus Aurantii were fry-processed. The conditions of frying technology were measured; the amounts of volatile oil before and after processing were determined with accurate volatile oil extractor; and the volatile oil in Rhizoma Atractylodis Macrocephalae and Fructus Aurantii was analyzed by means of GC.

Apiaceae↗

PubMed1998

[Cloning and mapping of the rpoB gene in M. tuberculosis].

OBJECTIVE: To clone the rpoB gene of M. tuberculosis. METHODS: Screening the rpoB gene of M. tuberculosis from M. tuberculosis genomic DNA library by using the rpoB gene conservative region PCR product as a probe. RESULTS: 411 bp products were seen after amplification of H37Ra DNA. The cloning and sequencing results indicated that the 411 bp products were homogeneous to M. tuberculosis rpoB gene. 12,000 clones of M. tuberculosis genomic DNA library were screened by hybridization using the 411 bp product as a probe and 7 clones seemed positive, 3 clones were real positive after the second hybridization. 1 of them carried a 3.8 kb insert fragment. The preliminary restriction map of the 3.8 kb segment was made. The regions which were found homogeneous to the probe to the end of this cloned fragment were 1 and 2.8 kb. CONCLUSION: In comparison with the open reading frame of H37Rv rpoB gene, the 3.8 kb segment cloned here covers larger portion of entire rpoB gene of M. tuberculosis. This study will provide a useful tool to study the resistant mechanism of rifampin and other rifamycin compounds to M. tuberculosis.

Antibiotics, Antitubercular↗

PubMed1998

[The experimental and clinical study of heliox in treating bronchial asthma].

OBJECTIVE: To evaluate the effects of breathing helium-oxygen(heliox: 79% He-21% O2) on bronchial asthma by way of experimental and clinical observations. METHOD: Six mongrel dogs were randomly inspired air or heliox after dripping 2% methacholine in its' tracheas controlled by 900C ventilator. During the experimental course, respiratory mechanical limits, hemodynamic index and blood gas values were observed. Eight asthmatic patients inspired heliox with assisted respirator of recycle-used helium, and the data of pulmonary function tests, arterial blood gas values of patients were recorded. RESULTS: The results demonstrated that heliox could reduce airway resistance, airway pressure and work of breathing, improve lung effective compliance, but had no effects on pulmonary circulation and systemic circulation. Heliox could ameliorate oxygen diffusion and CO2 eliminating, but the duration was very short after stopping breathing heliox. The assisted respirator of recycle-used helium could save helium distinctively, and the clinical application demonstrated that the instrument may be useful for pulmonary obstructive diseases. CONCLUSION: Heliox can reduce airway pressure, ameliorate oxygen diffusion and CO2 eliminating, so breathing heliox might be one of effective ways for asthmatic patients.

Adult↗

PubMed1998

[Radiological imaging in diagnosis for atypical pulmonary abscess].

OBJECTIVE: Evaluate characteristics of the radiological image of atypical pulmonary abscess. METHOD: The X-ray and CT image in 30 cases with atypical pulmonary abscess were analyzed. RESULT: The atypical pulmonary abscesses were classified into solitary ball type and irregular infiltration type. And these two types showed the following characteristics: circumscribed dissolution or small cavity; local congestion sign; coarse and long funiform shadow in margin; ambient circumscribed infiltrating shadow; adjacent pleural thickening and adhesion. CONCLUSION: Existence of abscess and perifocal inflammatory changes is the key to diagnose and differentiate this atypical variant of lung abscess.

Adult↗

PubMed1998

[Low-concentration nitrous oxide inhalation in the treatment of high-altitude pulmonary edema].

OBJECTIVE: To investigate the therapeutic effect of low-concentration of nitroic oxide (NO) inhalation in high-altitude pulmonary edema. METHOD: Sixty-five male patients with high-altitude pulmonary edema were randomized into three groups. Patients in the conventional therapy group received oxygen, intravenous furosemide, aminophylline and dexamethasone; patients in the nifedipine group received oral nifedipine (10 mg, tid) in addition to conventional therapy; and patients in the NO group received NO (10 ppm) inhalation for 30 min, in addition to oral nifedipine. The time for which pulmonary rales on auscultation and shadows on chest radiograph lasted, and the course of disease, were compared. RESULT: In the NO group, pulmonary rales disappeared in 0.4 +/- 0.3 d, shadows on chest radiograph disappeared in 0.6 +/- 0.2 d, and the course of disease was 1.8 +/- 0.7 d, all of which were significantly different from those of the nifedipine group (2.4 +/- 1.4 d, 4.1 +/- 1.7 d, 6.8 +/- 1.8 d, respectively) and the conventional therapy group (3.7 +/- 1.2 d, 5.5 +/- 1.8 d, 9.6 +/- 3.1 d, respectively). CONCLUSION: Low-concentration NO inhalation on the basis of conventional and nifedipine therapies was very effective in the treatment of high-altitude pulmonary edema, which deserves further and larger scale investigation.

Administration, Inhalation↗

PubMed1998

[Effect of tail suspension on mitochondrial Ca2+ and Mg2+ and parameters of electron microscopic morphometry in rats' skeletal muscle].

Changes of mitochondrial Ca2+, mitochondrial Mg2+ and parameters of electron microscopic morphometry in rats' skeletal muscle after 15 or 30 d tail suspension were observed. The results showed that mitochondrial Ca2+ [correction of Ma2+] mitochondrial Mg2+ increased and morphometry of mitochondrial in skeletal muscle showed that volume density (Vv), surface density (Sv), numerical density (Nv) increased. Mean volume (V) decreased. Specific surface increased in soleus muscle, while that parameter remain unchanged in gastrocnemus musles. It suggests that these changes may be denoted to the decrease of muscular contractive function in simulated weightlessness.

Animals↗

PubMed1998

[RP-HPLC determination of water-soluble active constituents and oleanolic acid in the fruits of Ligustrum lucidum Ait. collected from various areas].

The contents of p-hydroxyphenethyl-beta-D-glucoside, specnuezhenide and oleanolic acid in the fruits of Ligustrum lucidum collected from various areas in China were determined by reverse phase high performance liquid chromatography. The results could be used to evaluate the quality of the crude drug more comprehensively.

Chromatography, High Pressure Liquid↗

PubMed1998

[Experimental studies on anti-inflammatory, antipyretic and diuretic effects of several species of tongcao and xiao-tongcao].

OBJECTIVE: To observe and compare the anti-inflammatory, antipyretic and diuretic effects of three kinds of Tongcao(Tongtuomu, Panyezhangyeshu and Luosan) and seven kinds of Xiao-tongcao(Ximashanjinjiehua, Xinanxiuqiu1. 2., Ditanghua, Suixuezhangcai, Qingjiaye and Zhongguo jinjiehua). METHOD: Decoctions prepared from the above kinds of Tongcao and Xiao-tongcao crude drugs were given to rats at dosages of 8 g/kg and 4 g/kg by ig. Pharmacological actions were observed by means of carrageenan-induced swelling paws, fever models induced by beer-yeast or carrageenan and metabolic cage method in rats. RESULT: All the experimental decoctions could inhibit carrageenan-induced swelling of rat paws in different degrees and exerted anti-pyretic effect on rat fever models induced by beer-yeast or carrageenan. Three kinds of Xiaotongcao(Ximashanjingjiehua, Xinanxiuqui2., Zhongguojinjiehua) had obvious diuretic effect on rats. CONCLUSION: Decoctions of different species of Tongcao and Xiao-tongcao all have anti-inflammatory, antipyretic and diuretic effects, thus providing some pharmacologic basis for the efficacy assay, clinical application, species collation and quality study of Tongcao and Xiao-tongcao.

Analgesics, Non-Narcotic↗

PubMed1998

[Effect of yuanhua on isolated uterine strips in unpregnant rats].

OBJECTIVE: To explore the mechanism on the effect of Yuanhua on the contractile activity of isolated uterine strips in rats under artificial oestrum. METHOD: Isolated strips were suspended in a tissue chamber in which Yuanhua was added with some antagonists of inhibitors or without. RESULT: Yuanhua could excite the uterine smooth muscle strips in a dose-dependent manner, but atropine, phentolamine, hexamethonium and diphenhydramine could not inhibit this exciting action. This exciting effect could be inhibited completely by verapamil and decreased by indomethacin(inhibitor of prostaglandin synthase). CONCLUSION: The exciting effect of Yuanhua on un-pregnant rats in vitro might be related to an action on the cell membrane Ca2+ channel as well as to a partial stimulation of synthesis and release of PG.

Animals↗

PubMed1998

[Analysis of nuclear DNA gene types of Leishmania isolates from hilly and plain foci of China].

AIM: To analyse the nuclear DNA (nDNA) polymorphism of Leishmania isolates from hilly and plain foci of China. METHODS: nDNA were analysed by endonuclease digestion, Southern blotting and chromosomal localization. Probes were labeled with digoxigenin. RESULTS: Using gp63 gene probe, similar hybridization bands were found to be existed between nDNAs of Leishmania donovani Jiangsu human isolate and L. d. Jeddah, also between nDNAs of L. d. Sichuan human isolate and L. infantum. Using beta-tubulin gene probe, there were two similar hybridization bands existed between nDNAs of L. d. Jiangsu human isolate and L. d. Jeddah, and three similar hybridization bands existed between nDNAs of L. d. Sichuan canine isolate and L. d. Gansu canine isolate, and two similar hybridization bands existed between nDNA of L. d. Sichuan canine isolate and L. d. Wenchuan human isolate. CONCLUSION: Homology exists between L. d. Jiangsu human isolate and L. d. Jeddah from plain foci, between L. d. Sichuan human isolate from hilly foci and L. infantum, between L. d. Sichuan canine isolate and L. d. Gansu canine isolate from hilly foci. Homology as well as differences exist between L. d. Sichuan canine isolate and L. d. Wenchuan human isolate. Heterogeneity exists between isolates from hilly foci and plain foci.

Animals↗

PubMed1998

[Studies on flavones of Epimedium bevicorum Maxim].

OBJECTIVE: To systematically develop Epimedium spp. and control their quality. METHOD: Using polyamide and macroporous adsorbent resins AB-8. The compounds were identified on the basis of spectrometric data and physical and chemical test. RESULT: Four flavones were isolated from the herb. They were identified as wushanicariin, baohuoside VI, kaempferol-3,7-O-alpha-L-dirhamnoside and hexandraside E. CONCLUSION: These flavones were isolated from the herb and identified for the first time.

Drugs, Chinese Herbal↗

PubMed1998

[Preliminary studies on pharmacological actions of tongca and xiao-tongcao polysaccharides].

OBJECTIVE: To study and compare the immunologic function and antioxidative effect of Tongcao(Tongtuomu) and Xiao-Tongcao(Ximashanjingjiehua, Xinanxiuqiu, Ditanghua) polysaccharides. METHOD: Mice were abdominally administrated with four kinds of polysaccharides at dosages of 80 mg/kg and 40 mg/kg for 7-10 days. RESULT: Four kinds of polysaccharides could increase the serum-lysozyme activity, phagocytic function of MPS and the serum hemolysin-antibody level in mice, inhibit the delayed hypersensitivity induced by DNCB in mice and raise the serum-catalase activity in mice. CONCLUSION: Four kinds of Tongcao or Xiao-Tongcao polysaccharides have immunoregulative function and antioxidative effect. The results could enrich the contents of "A Study on Species-Sorting and Quality of Tongcao-Xiao-Tongcao Crude Drugs".

Adjuvants, Immunologic↗