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Biomedical subjects

Ying Liu

Publications and source records attributed to Ying Liu.

At least 433 records · Page 24Linked to original sources
PubMed2002

[Diagnosis, treatment and prognosis of thymoma: analysis of 116 cases].

OBJECTIVES: To study the diagnosis and treatment of thymoma and to assess prognosis factors. METHODS: The clinical data on 116 patients with thymoma were collected. A retrospective analysis was performed by comparison of their survival rates computed by the actuarial method and rate of recurrence and metastasis. RESULTS: Chest radiograph was used chiefly for the preoperative diagnosis of thymoma; myasthenia gravis (MG) (25.0%, 29/116) was the most common paraneoplastic disease. An extensive and radical resection was carried out to reduce the recurrence rate of thymoma with stage I and stage II (chi(2) = 4.941 P = 0.0219). The survival time was prolonged by postoperative radiotherapy and chemotherapy. A strong correlation was noted between the clinical stage and histologic subtype of M-H classification, by which the invasive behavior of thymoma was predicted (r = 0.385, P = 0.007). The 3-, 5-, and 10-year survival rates were 81.2%, 67.9% and 40.5%, respectively. Statistical analysis showed a significant negative correlation between stage and survival rate (r = -0.897, P = 0.0000). CONCLUSION: The prognosis of thymoma depends mainly on the histologic subtype, clinical stage and multimodality treatment rather than paraneoplastic diseases.

Adolescent↗
PubMed2002

[Comparison of leaf tissue turnover for Leymus chinensis and Phragmites communis after grazing].

Leaf tissue turnover of Leymus chinensis and Phragmites communis after grazing was studied by application of theory and method of tissue turnover in this paper. The results showed that the number of living leaf of P. communis was larger than that of L. chinensis, but the length of living leaf of L. chinensis was larger than that of P. communis during the whole growth period. Both of the leaf appearance rate and the leaf elongation rate of L. chinensis and P. communis were largest at first, and then they decreased gradually. The rate of leaf wither and leaf senescence were in the converse trend. The leaf lifespan of P. communis was shorter than that of L. chinensis. The velocity of leaf tissue turnover of P. communis was faster than that of L. chinensis. There would be a great loss if the leaf tissue of L. chinensis were not used in time. The quality of grasslands could be improved by different utilization ways and periods.

Animals↗
PubMed2002

[Enhancing hGH expression level in insect cells by shortening the 5'-UTR of hGH cDNA].

The regulation of foreign gene expression in Insect-Baculovirus Expression System is very complex. In this report, the effect of 5'-UTR in the expression of hGH gene in cultured Sf9 cells was examined. A 18 bp length in the end of 5'-UTR of hGH (human Growth Hormone, hGH) cDNA including a stem-loop structure was deleted by PCR. The truncated hGH cDNA, delta 1hGH was cloned in pFastBac1, named pFast-Bac-delta 1hGH. After transforming into E. coli. DH10Bac, which have a shuttle vetor-Bacmid, the delta 1hGH was integrated into Bacmid by site-specific transposition, and an expression vector, rBacmid-delta 1hGH DNA was acquired. By transfecting the cultured Sf9 cells with the recombinant expression vector DNA, pure recombinant virus, rAcV-Bac-delta 1hGH was obtained, and hGH gene was expressed. Immuno-blot and Chemiluminescent assay revealed that the expressed hGH had normal immunological activity, the amount of hGH expression level in Sf9 cell supernatant infected with rAcV-Bac-delta 1hGH containing the truncated 5'UTR was four to five times higher than that infected with rAcV-Bac-hGH.

5' Untranslated Regions↗
PubMed2002

[Influence of preoperative radiotherapy on resection rate and long-term efficacy for patients with stage II and III lung carcinomas].

BACKGROUND & OBJECTIVE: It is difficult to diagnose lung carcinomas in early stage. Quite a few patients are in advanced stages(partial stage IIIb and IV) and unsuitable for surgical treatment when they come to see doctors with some clinical symptoms. For some patients with stage II and III lung carcinomas, especially associated with ipsilateral hilar and/or mediastinal lymph nodes metastasis, it is very difficult to resect the tumors, or the patients can't tolerate double lobectomy or pneumonectomy because of cardio-pulmonary function deficiency. For these patients, preoperative radiotherapy was chosen firstly in the past, in order to improve resection rate and long-term efficacy. The aim of this study was to explore the effect of resection rate and long-term efficacy of preoperative radiotherapy for stage II and III lung carcinomas. METHODS: From 1985 to 1995, 62 patients with lung carcinomas (group A) received preoperative radiotherapy and operation. At the same time, 1615 patients with lung carcinomas (group B) received operation alone. The resection rate, 3 and 5-year survival rates and the incidence of postoperative complications for stage II and III lung carcinomas were analyzed. RESULTS: There were no significant differences of the resection rate(84.2% vs 84.5%, chi 2 = 0.187, P > 0.05), as well as the 3 and 5-year survival rates(chi 2 = 9.86, P > 0.05) between the two groups for stage II and III lung carcinomas. The incidence of complications of group A for stage II and III lung carcinomas was higher than that of group B(12.3% vs 5.8%, chi 2 = 6.84, P < 0.05). CONCLUSIONS: Preoperative radiotherapy is helpless to improve the resection rate and the long-term survival rate of stage II and III lung carcinomas. In our opinion, it should not be taken into consideration unless it enables surgical resection to be done in the patients with inadequate pulmonary reserve and achieve the same surgical margin as a pneumonectomy.

Adenoma↗
PubMed2002

[The activity of M-phase promoting factor in oral normal tissue and tumor].

OBJECTIVE: To investigate the content and activity of M-phase promoting factor (MPF) in pleomorphic adenoma, mucoepidermoid carcinoma, buccal carcinoma and normal tissue, in order to evaluate the role of MPF in the development of tumor and the relationship between MPF and malignant degree. METHODS: The content and activity of MPF were assessed by immunobloting and Gollicano method. RESULTS: The cdc2 and cyclinB (two subunits of MPF) were found both in normal and tumor tissues, and their content in tumor was higher than normal tissues. Buccal carcinoma was 64% higher than normal tissues. The activity of MPF in carcinoma was higher than normal tissue and had positive relation with the malignant extent. CONCLUSIONS: The content and activity of MPF in tumor are higher than normal tissue. PKC can activate MPF. These results show PKC may promote tumor proliferation by activating MPF and also, the activity of MPF has some relation with malignant extent.

CDC2 Protein Kinase↗
PubMed2002

Endotoxin removal in some medicines and human serum albumin solution by affinity membranes.

Three kinds of affinity membranes utilized for endotoxin removal, namely, chitosan affinity membrane (KFCC517), hydrophobic and cationic charged membrane (KFCG316) and metal chelate affinity membrane (KFCM402) were prepared by using cellulose membrane as support. The adsorbability and applications of the membranes in endotoxin removal were investigated. The results showed that all of these affinity membranes could be utilized for endotoxin removal in several kinds of solutions. The factors affecting endotoxin removal such as ionic strength, pH value and flow rate were investigated, and the results were discussed. Three cartridges of membranes KFCC517, KFCG316 and KFCM402 were utilized for endotoxin removal in human serum albumin solution. The cartridge of membrane KFCC517 also was utilized in medicine injections, such as hydrocortisone, puerarin, tetracaine hydrochloride and dextran 40 glucose. Under the optimal conditions, the removal efficiencies of endotoxin were over 80% and the recoveries of desirable substances were over 95%.

Adsorption↗
PubMed2002

[Inhibitory effects of genistein on the synthesis of DNA and the protein expression of cyclin D1 in human gastric carcinoma cell-line].

In order to study the inhibitory effects of genistein on the growth of human gastric carcinoma cells and to explore its possible mechanism, cell proliferation and DNA incorporation tests are applied. Immunocytochemistry is also applied in this study to detect the protein expression of cyclin D1 after the cell-line is exposed to genistein. The results showed that the growth of the cells and the synthesis of DNA is decreased in a marked dose-dependent manner after the treatment with genistein. Genistein also decreased the protein expression of cyclin D1. The above mentioned results indicate that genistein inhibits the growth of gastric carcinoma cells and the possible mechanism of this inhibition might be resulted from inhibiting the synthesis of DNA and the protein expression of cyclin D1.

Adenocarcinoma↗
PubMed2002

[Target chemotherapy of intestinal nematode infection in area with low endemicity].

OBJECTIVE: To evaluate the control measures for intestinal nematodiasis in endemic area with low prevalence and intensity of infection. METHODS: Target chemotherapy was carried out in high-risk population based on the epidemiological characteristics such as age and clinical findings. Albendazole and mebendazole were administered each 200 mg once daily every year for 3 or 5 years. Saturated brine floatation and Kato-Katz thick smear techniques were used for stool examination to evaluate the efficacy of treatment. RESULTS: Two hundred residents from each of the three investigation villages were selected for target chemotherapy once a year for three years. The prevalence of intestinal nematodes decreased from 6.2% in 1995 to 5.4% in 1996 and 3.2% in 1997, and remained at 2.3% after three years in 2000. One control village where only primary school students were treated once a year for 5 years, the prevalence of Ascaris and Trichuris infection also decreased from 1.4% and 4.2% in 1995 to 0.9% and 1.4% in 2000, respectively. The target chemotherapy on the predisposed population to hookworm infection showed that the prevalence in the population above 41 years old was declined from 19.4% to 10.9%. CONCLUSION: The target chemotherapy is an economical and effective approach for the control of intestinal nematode infection in endemic area with low prevalence and intensity of infection.

Adult↗
PubMed2002

[Effect of isoflavone on human breast cancer cell line MCF-7 and its probable mechanism].

The effects of isoflavone on human breast cancer cell line MCF-7 growth and apoptosis and its probable mechanisms were studied in vitro. The results showed that isoflavone could significantly inhibit the growth and induce the apoptosis of MCF-7 cells. Western Blotting showed that isoflavone increased iNOS protein expression. These results suggested that isoflavone significantly inhibited the MCF-7 growth and induced cell apoptosis by regulating iNOS gene expression.

Antineoplastic Agents↗
PubMed2002

[Endoscopic sinus surgery for recurrent sinusitis and nasal polyps].

OBJECTIVE: To study the treatment methods of improving the operative effect and reducing the complications of chronic sinusitis and nasal polyps. METHOD: Two hundred and eighty cases with chronic sinusitis and nasal polyps were performed with endoscopic sinus surgery. RESULT: The long-term follow-up was performed at 6 and 12 months after operation, the results showed that the total effective rate were 85.75% (the cure rate was 58.2%; the improvement rate was 27.5%) and 81.4% (the cure rate was 54.6%; the improvement rate was 26.8%) respectively, the complication rate was 9.3%. CONCLUSION: Correct operation choices, preoperative and postoperative combing treatment and excellent surgical skills are keys of improving the operative effect and reducing the complications.

Adolescent↗
PubMed2002

[Clinical analysis of 80 perinatal death from hepatic diseases in pregnancy].

OBJECTIVE: To explore the factors associated with perinatal death of hepatic diseases in pregnancy (HDIP) and make feasible suggestions and measures for perinatal care of high risk patients. METHODS: The 80 perinatal death cases of hepatic diseases in pregnancy (HDIP) during 1991-2000 in our hospital were analyzed retrospectively. RESULTS: The perinatal mortality of HDIP in our hospital during the last 10 years was 17.99 approximately 65% was in utero death. Perinatal mortality was different between male (21.64%) and female (10.11%) (P<0.01). Compared first 5 years with last 5 years author found that the perinatal mortality of HDIP had no significant decrease (P>0.05). The perinatal mortality in city and suburbs had decreased, while in the floating population from other provinces the perinatal mortality had increased. The perinatal death was mainly caused by pregnancy induced hypertension (PIH) and asphyxia. But for the HBV carrier mothers the causes of death included umbilical cord problems, premature rupture of membrane and asphyxia. CONCLUSIONS: The perinatal death mortality was increased by HDIP, deaths were essentially associated with pregnancy induced hypertension and asphyxia and the floating population and male gender were high risks. To enhance the management of HDIP or immigration, take effective therapies of hepatitis and improvement of resuscitation of newborns are critically important.

Adolescent↗
PubMed2002

[Abdominal and pelvic lymph nodes in non-Hodgkin lymphoma: the nodal distribution in Chinese patients].

OBJECTIVE: To study the distribution of abdominal and pelvic lymph nodes involved in non-Hodgkin lymphoma in Chinese patients. METHODS: CT images of 241 non-Hodgkin lymphoma patients with abdominal and pelvic lymph nodes involved were reviewed. Of them, 96 patients whose clinical and image data fulfilled the requirements of the analysis were included: 1. Positive abdominal and/or pelvic nodular lesion in untreated patients examined by CT (n = 74). 2. New lesions in abdominal or pelvic lymph nodes who never had any nodular lesion by previous abdominal and/or pelvic CT (n = 14). 3. Treated patients who did not have abdominal and/or pelvic CT before, showed regression of initial disease for at lease 6 months after chemotherapy and patients showing abdominal and/or pelvic nodal lesions (n = 8) were assessed. In accordance with Clinical Schema for the Lymphoid System, these patients were divided into 3 histology subtypes: indolent (IL; n = 31), aggressive (AL; n = 61) and very aggressive (VAL; n = 2) lymphoma. The remaining 2 cases were unclassified (UCL). Both abdominal and pelvic CT scans were undertaken in 46 patients, abdominal CT only in 47 patients and pelvic CT only in 3 patients. Enhanced CT with i.v. contrast was obtained in 80 patients. The anatomic sites involved were designated as retroperitoneal (i.e. paraaortic), mesenteric, abdominal (i.e. celiac, paracardiac, gastrohepatic, and hepatic hilar, etc), retrocrural, subdiaphragmatic, common iliac, internal iliac, external iliac, and inguinal nodes, respectively. RESULTS: The lesions were located in the retroperitoneum, with an incidence of 83% for both IL and AL. These were predominantly seen superior and inferior to the renal hila, with incidences of 72.0% (18/25) in IL and 67.3% (33/49) in AL. Pelvic lymph nodes came the next, with incidences of 41.9% (126/301 sites of IL and AL), 57.5% (50/87 sites) in IL and 35.5% (76/214 sites) in AL. Mesenteric lymph nodes stood third with incidences of 37.1% (33/89 IL and AL), 43.3% (13/30) in IL and 33.9% (20/59) in AL. There was only one statistically significant evidence that the external iliac lymph nodes were much more commonly seen in IL than in AL (P < 0.05). CONCLUSION: In Chinese patients, retroperitoneal, iliac, and mesenteric nodes are the most commonly involved lymph nodes in NHL. The involved retroperitoneal lymph nodes are predominantly located superior and inferior to the renal hila. The anatomic distribution of abdominal and pelvic lymph nodes in NHL of Chinese patients is different from that of the western countries.

Abdomen↗
PubMed2002

[Association of polymorphism of human beta 2-adrenergic receptor gene and bronchial asthma].

OBJECTIVE: To investigate whether beta 2-adrenergic receptor gene (beta 2AR) polymorphism at position 16, 27, 164 is in association with asthma susceptibility or asthmatic phenotype (including nocturnal asthma, serum IgE level, bronchial responsiveness, the status of asthmatics). METHODS: By using PCR-RFLP and allelic-specific PCR (ASP), the polymorphism of beta 2AR gene at position 16, 27, 164 in 125 Han origin asthmatics and 96 normal healthy controls with the same ethnic nearby Beijing region were genotyped. All patients had their serum total IgE (TIgE) measured by RAST, pulmonary ventilatory function assessed by FEV1% and FEV1/FVC, bronchial responsiveness challenged by methacholine (if FEV1% > 70%), and brocho-reversibity by inhaling beta 2-agonist. RESULTS: There was higher prevalence of Gly16 homozygous of beta 2AR in asthmatics than that in normal healthy controls (22.4% vs 8.3%, P < 0.05), with odd ratio (OR) 2.918 (95% CI: 1.256-6.781); Also there was higher frequency of Gly16 homozygous of beta 2AR in nocturnal asthmatics than that in nonnocturnal asthmatics (35.3% vs 13.5%, P < 0.01), but Gly16 homozygous of beta 2AR was low an independent risk factor for the pathogenesis of asthma. The dose of methacholine was low in asthmatics carrying Gln27 homozygous beta 2AR than Glu27 homozygous beta 2AR and Gln/Glu27 heterozygous beta 2AR in brocho-challenge test [(0.205 +/- 0.275) vs (2.11 +/- 3.00) vs (1.575 +/- 0.828) mumol, P < 0.05]. CONCLUSIONS: Gly16 homozygous beta 2AR was associated with asthma susceptibility in Chinese patients with Han ethnic nearby Beijing region, and Gly16 homozygous beta 2AR was associated significantly with nocturnal asthma. Glu27 homozygous beta 2AR was related to hyper-bronchial reactivity of asthmatics.

Asthma↗
PubMed2002

[Polarization characteristic of LiF polarizer at UV-VUV spectral range].

A method of determinating the degree of polarization of grating, polarizer and analyzer at some wavelength is introduced. The degrees of polarization of LiF polarizers were determined with 1 m Seya-Namioka monochromator by this way. The source is hollow cathode source. The degrees of polarization of two, four and eight LiF plates were measured at 120, 149.2, 174.2, 214.2, 235.0, 300 and 340 nm. The theoretical and experimental reults were consistent within the error. The angular extinction dependence of the LiF polarizer and analyzer was measured at VUV wavelengths. The results showed the expected cosine square dependence, so a high degree of polarization was indeed produced. Also, the LiF polarizer was used to measure the polarization characters of the Al + MgF2 reflectance and the absolute grating efficiency at both parallel and perpendicular to their incident plane.

Aluminum↗
PubMed2002

[Polarization characteristic of Al + MgF2 film at VUV].

Polarization characteristic of Al + MgF2 is researched theoretically and experimentally. According to the theory of electromagnetism, the reflectance perpendicular and parallel to the incident plane of Al + MgF2 is calculated in the way of matrix optics. The effect of incident conditions and thickness of MgF2 is considered on the reflectance of Al + MgF2 coatings. The MgF2 not only prevents the oxidation of aluminum but also increases the reflectance of Al + MgF2 by interference. The polarization of Al + MgF2 is analyzed using the concept of ratio of extinction based on above mentioned calculations. The polarization character of Al + MgF2 and single Al coating is compared. The reflectances perpendicular and parallel to the incident plane of Al + MgF2 film are measured at VUV range, using LiF polarizer as a VUV polarizer. So the polarization character of Al + MgF2 is researched experimentally. Both theoretical and experimental results of the polarization character of Al + MgF2 are coincident.

Aluminum↗
PubMed2001

The platelet receptor GPVI mediates both adhesion and signaling responses to collagen in a receptor density-dependent fashion.

The platelet response to collagen is a primary event in hemostasis and thrombosis, but the precise roles of the numerous identified platelet collagen receptors remain incompletely defined. Attention has recently focused on glycoprotein VI (GPVI), a receptor that is expressed on platelets in association with a signaling adapter, the Fc receptor gamma chain (Fc Rgamma). Genetic and pharmacologic loss of GPVI function results in loss of collagen signaling in platelets, but studies to date have failed to demonstrate that GPVI-Fc Rgamma expression is sufficient to confer collagen signaling responses. These results have led to the hypothesis that collagen responses mediated by GPVI-Fc Rgamma may require the collagen-binding integrin alpha2beta1 as a co-receptor, but this model has not been supported by a recent study of mouse platelets lacking alpha2beta1. In the present study we have used a novel anti-GPVI monoclonal antibody to measure the level of GPVI on human platelets and to guide the development of GPVI-expressing cell lines to assess the role of GPVI in mediating platelet collagen responses. GPVI receptor density on human platelets appears tightly regulated, is independent from the level of alpha2beta1 expression, and significantly exceeds that on previously characterized GPVI-expressing RBL-2H3 cells. Using newly generated GPVI-expressing RBL-2H3 cells with receptor densities equivalent to that on human platelets, we demonstrate that GPVI expression confers both adhesive and signaling responses to collagen in a graded fashion that is proportional to the GPVI receptor density. These results resolve some of the conflicting data regarding GPVI-collagen interactions and demonstrate that 1) GPVI-Fc Rgamma expression is sufficient to confer both adhesion and signaling responses to collagen, and 2) GPVI-mediated collagen responses are receptor density-dependent at the receptor levels expressed on human platelets.

3T3 Cells↗