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Biomedical subjects

Z Yang

Publications and source records attributed to Z Yang.

At least 523 records · Page 29Linked to original sources
PubMed1998

[Determination of taurine in food by high performance liquid chromatography].

Taurine in food was separated by HPLC as its phthalaldehyde-ethanethiol derivative on mu-Bondapak C18 reverse column and measured at 330 nm. The determination was not interfered by sulphosalicylic acid, excess dervatizing reagents and 20 kinds of amino acids. The stability of the taurine dervatives was discussed in this paper. The result showed that the higher concentration of borate buffer, the more stable of taurine derivatives and the lower concentration of taurine, the faster decomposition of taurine dervitives. Using more concentrated borate buffer (0.4 mol/L) and controlling the time between injection and reaction and keeping the operation identically could avoid the effect of nonstable taurine derivatives in the determination. The minimum detectable quantlity was 8 ng. The coefficient of variation was less than 8%. The recoveries were 90.7%-105.1%.

Animals↗
PubMed1998

[Study of the liver changes by B-ultrasound and histopathology in severe pregnancy induced hypertension].

OBJECTIVE: To investigate the liver changes in severe pregnancy induced hypertension (PIH) on B-ultrasound and pathological examination and to detect a possible connection with fatty liver of pregnancy. METHODS: From Jan 1992 to Nov 1997, 90 pregnant women in the third trimester were enrolled for study. They were divided into 3 groups: the pregnant women with liver diseases; mild and moderate PIH; and severe PIH (30 cases each). Ultrasonography of the liver was performed on each patient after admission. 15 percutaneous liver biopsies were performed under the guidance of real-time ultrasound scans on 15 severe PIH patients with or without liver dysfunction. Tissues were stained with specific lipid staining (Sudan) and with hematoxylin-eosin. All specimens were analyzed by light microscopy. RESULTS: Fatty liver was observed by B-ultrasound in 2 and 12 cases of the pregnancy with liver diseases group and the severe PIH group, respectively. 14 of the 15 liver biopsy specimens showed fatty infiltration of varying degrees. however, only 8 of the 14 cases were detected fatty liver by B-ultrasound. CONCLUSIONS: These findings suggest that liver involvement in severe PIH is a pathological change. Severe PIH and acute fatty liver in pregnancy could have related pathogenesis components of the same.

Adult↗
PubMed1998

[Influence of insufficient zinc on immune functions in NIDDM patients].

The serum zinc level and immune functions were analyzed in 34 patients with NIDDM before and after the treatment with zinc gluconate supplement during conventional therapy (after the blood glucose level stabilization). The results showed that before treatment the level of serum zinc and red cell C3b receptor rosette(RBCK-C3b RR), T-lymphocyte subgroup CD3, CD4, and CD4/CD8 were decreased(P < 0.01), while CD8, red cell immune complex rosette(RBC-ICR) were increased. After treatment with zinc gluconate for 1 month the serum zinc level, RBC-C3b RR, RBC-ICR, CD3 and CD4/CD8 became normal, CD8 also approached to normal. All the above figures were significantly different before and after zinc therapy. The data showed that various degrees of lowering of serum zinc and abnormal immune functions were present during the conventional antidiabetic therapy. Thus, zinc supplement should be used as an important adjunctive therapy for NIDDM patients.

Adult↗
PubMed1998

[Expression and significance of tumor suppressor gene WAF1 in epithelial ovarian neoplasms].

The expression of P21WAF1 protein in epithelial ovarian carcinoma, borderline ovarian tumor, benign ovarian tumor and normal ovary were analyzed by immuno-histochemistry technique. Results indicated: 1. The positive expression for p21 was 45.7%(16/35) in epithelial carcinoma, 75%(9/12) in borderline tumor and benign tumor, 90.9%(10/11) in normal ovary. The difference for p21 protein between ovarian carcinoma and borderline tumor, benign tumor, normal ovary was obvious(P < 0.05). The differences in other groups were unimportant(P > 0.05). 2. The positive expression of p21 in stage I/II was 42.9%(6/14), in stage III/IV was 47.6%(10/21). The difference of them was insignificant(P > 0.05). 3. The positive expression for p21 in Grade I was 70%(7/10), in Grade II 50%(6/12), in Grade III 23.1%(3/13). The difference for p21 protein between Grade III and Grade I, Grade II was obvious(P < 0.05). The difference between Grade I and Grade II was unimportant(P > 0.05). 4. The positive expression for p21 in 35 ovarian carcinoma with lymphaden metastasis(17.6%) was lower than ovarian carcinoma without lymphaden metastasis(72.2%). The difference of them was obvious(P < 0.05). The conclusion is that deregulation of p21 protein is associate with tumoral differentiation, lymphaden metastasis and patient's prognosis, whereas it isn't associated with clinical stage. The loss for p21 protein may effect the onset and progress of ovarian carcinoma.

Carcinoma↗
PubMed1998

[Transnasal endoscopic surgery of skull base].

This article will discuss our experience in managing 54 cases of benign and malignant lesions of skull base using endoscopic transnasal approaches surgery technique since 1991, emphasizing general principles for management and specific details for individual lesions including cerebrospinal fluid rhinorrhea repair, optic nerve decompression, obliteration of empty sella, pituitary tumor resection, and malignant tumor resection. In the result, endoscopic transnasal approach were used successfully in all the cases, it indicates that the new technique is a safe, valuable and efficient procedure for management of some lesions of skull base.

Adolescent↗
PubMed1998

[Comparative studies of ciliary epithelial morphological and radiologic findings in the osteomeatal complex].

In this study, we evaluated quantitatively preoperative coronal CT scan in 30 nasal cavities of 22 patients with chronic sinusitis who underwent functional endoscopic sinus surgery. The ciliated area of the osteomeatal complex (OMC) from these patients was quantitatively observed by scanning electron microscope and image analysis. Our results showed a positive correlation between ciliary epithelial pathological changes in OMC and disease degree of this area in CT scan.

Adult↗
PubMed1998

[Changes of thromboxane A2 receptors and their mRNA expression and effects of their antagonist phenol red in the lung of acute lung injury of rats].

OBJECTIVE: To investigate the changes of thromboxane A2 receptors and the influence of their antagonist phenol red, and to study in molecular level the mechanism of action of thromboxane A2 in acute lung injury. METHODS: Acute lung injury model of rats was produced by oleic acid, and phenol red (5 mg/kg, 50 mg/kg) was injected via vein 5 minutes before oleic acid injection. Changes of thromboxane A2 receptors and their mRNA expression in the lung were determined at 6 hours after oleic acid injection. RESULTS: Down-regulation of thromboxane A2 receptors were observed, but their mRNA transcription increased significantly in the lung after oleic acid injection. The injection of phenol red before oleic acid could induce down-regulation of thromboxane A2 receptors and abolish the increase of their mRNA transcription after oleic acid injection. Phenol red could reduce LBI, RLW and improve PaO2. Histological examination of lung tissues demonstrated that the degree of lung injury had been reduced significantly. CONCLUSION: Thromboxane A2 plays an important role plays in pathological processes of acute lung injury. Phenol red in vivo could effectively reduce severity of acute lung injury by blocking thromboxane A2 receptors and regulating the expression of thromboxane A2 receptors.

Animals↗
PubMed1998

[Endoscopic transsphenoidal approach in surgical treatment of pituitary adenomas].

OBJECTIVE: To recognize the indications and the value of endoscopic transsphenoidal approach in surgical treatment of pituitary adenomas. METHODS: The management of pituitary adenomas in 24 patients was reviewed. RESULTS: Endoscopic transnasal transspheniodal approach was used successfully in 24 cases and endoscopic transseptal transsphenoidal approach was used successfully in 4 cases, total tumor resection in 23 cases and subtotal resection in 1 case were achieved. CONCLUSION: This new technique offered a simple and rapid access to the sella turcica, and also, direct visualization which improve the surgeon's ability to resect tumors, it is a safe, valuable and efficient procedure for removing pituitary adenomas. The indications and management of the complications of endoscopic pituitary surgery were discussed.

Adenoma↗
PubMed1998

[Surgery of advanced clival tumors].

OBJECTIVE: To investigate the effects of surgical procedures on tumor 27 patients with advanced clival tumors during the last 9 years. METHODS: Four different kinds of surgical approaches were selected and used according to preoperative clinical and radiographic findings, and the complications and the long-term survival rates were evaluated after the surgical procedures. RESULTS: All of the 8 patients with benign clival tumors (6 cases with chordomas and 2 with meningiomas) had over 2-8 years survival and no severe complications after the surgical procedures and adjuvant radiotherapy. Fourteen of the 19 patients with malignant tumors had over 2-6 years survival (a survival rate of 73.7%) after the surgical procedures, the adjuvant chemotherapy and radiotherapy. CONCLUSION: Surgery of the clivus appears to be worthwhile procedure for improving outcome of the patients with advanced clival tumors.

Adolescent↗
PubMed1998

[Diagnosis and surgical treatment of pituitary microadenoma].

OBJECTIVE: Through the experiences of clinic picture and the radiologic characteristics of eleven cases of micropituitary adenomas, the early diagnosis and surgical indications were discussed. METHODS: Intensified CT and MRI were used to compare their significances in the diagnosis of micropituitary adenomas. Kaltai incision of the nares and transsphenoidal approach were adopted in these cases. RESULTS: The bulging of the upper border of the pituitary gland and the shifting position of the pituitary stalk observed in the intensified MRI are the pathognomonic signs for the diagnosis of micropituitary adenoma. The operation was stopped due to hemorrhage in one case. The average following up was 3.2 years past operative death in the second month in one case, operative failure in one case and loss of following up in one case. CONCLUSION: Strict selection of surgical indications must be done necessary after careful study of MRI.

Adenoma, Chromophobe↗
PubMed1998

[Model of human nasal gland cells cultured in collagen gels].

OBJECTIVE: To establish a culture model of human nasal gland (HNG) cells in collagen gels. METHOD: The HNG cells were cultured in collagen gels. RESULTS: The HNG cells cultured in collagen gels showed 3-D outgrowth. After one week culture, the HNG cells developed ductal projections, the sections of collagen gel culture examined by light microscopy showed cross sectional area of tubules with a lumen containing secretory products. The cells contained numerous secretory granules. Electron microscopy showed 3-D cultured HNG cells forming a well defined lumen inside the tubular formation. These cells were polarized and interconnected by junctional complexes and possessed extensive microvilli along all their luminal border. Secretory products in the lumen and the cells located close to the luminary surface were intensely stained blue by AB-PAS staining. Immunohistochemical staining of cells labeled with a rabbit antiserum against human lysozyme showed 90% positivity. CONCLUSION: These data indicated that HNG cells altered their phenotypes when cultured in vitro and changed from differentiated serous and mucous cells toward intermediate seromucous cells.

Cell Differentiation↗
PubMed1998

[Measurement of blood flow in nasal mucosa].

OBJECTIVE: To determine the amount of blood flow in the human nasal mucosa and its change in patients with nasal polyps and allergic rhinitis. METHODS: Using the Ameflow-H2, the amount of blood flow in nasal mucosa was examined in 98 normal adults, 18 cases of nasal polyps and 14 cases of allergic rhinitis before and after application of the vaso constrictor. RESULT: Before the application of the vaso constrictor, blood flow of nasal mucosa of patients with nasal polyps and allergic rhinitis was lower than that of healthy people (P < 0.01). After using the vaso constrictor, the amount of blood flow was decreased in all cases with a significant decrease in patients with nasal polyps. CONCLUSION: Ameflow-H2 may be the best tool to measure nasal blood flow than other devices. The method is technically simple, less traumatic, and repeatable.

Adolescent↗
PubMed1998

[Cloning and sequencing of the VL and VH genes from the anti-vascular endothelial growth factor McAb hybridoma cell line].

OBJECTIVE: The light chain variable region (VL) and heavy chain variable region (VH) genes from the anti-VEGF165 McAb hybridoma cell line were cloned for construction of it's chimeric antibody. METHODS: The VL and VH genes were amplified from the total RNA of the VmD11 hybridoma with RT-PCR and cloned into vectors, and then analyzed by sequencing. RESULTS: The 320 bp VL gene belong to mouse kappa light chain subgroup V, the 354 bp VH gene belong to mouse heavy chains subgroup I (B). CONCLUSIONS: The nucleotide sequence analysis indicated that the cloned genes coded the light and heavy chain variable region of mouse respectively.

Amino Acid Sequence↗
PubMed1998

[Evaluation of the treatment effect for bruxism by using myomonitor and occlusal splint].

OBJECTIVE: To evaluate the treatment effect of bruxism by using myomonitor and occlusal splint therapy. METHODS: By using EMG, audiocontrolled recorder and myollectronic recording device to record and analyse the muscles functional state before and after treatment. RESULTS: Splint therapy was more effective than the myomonitor did, such as teeth grinding stopped in 12 cases to 1 case, grinding time decreased in 13 cases to 10 cases and no significant effect in 2 cases to 17 cases. SPD and V/T curve slope of muscles decreased. CONCLUSION: This indicates that the functional state of masticatory muscles got improved. Splint therapy is one of the effective treatment method for bruxism.

Adult↗