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Biomedical subjects

Z Li

Publications and source records attributed to Z Li.

At least 613 records · Page 34Linked to original sources

[The study on superoxide dismutase and trace element in patients with senile cataract].

PURPOSE: To investigate the relation of senile cataract with superoxide dismutase(SOD) and trace elements. METHODS: Superoxide dismutase of red blood cells and trace elements(Cu, Zn, Ca, Fe) of serum in 61 patients with senile cataract and 121 normal persons were investigated. RESULTS: The activity of superoxide dismutase in patients with senile cataract decrease dramatically in comparison with normal control, and there was no statistical difference about trace elements of Cu, Zn, Ca between senile cataract and control group. But Fe element in patients is higher than that of the normal group. CONCLUSION: The results support the hypothesis that the formation of senile cataract is capable of antioxidative scavenger system of lens decreases with age.

Aged↗

[The hereditary liability of otosclerosis and the strategies for treatment and prevention].

OBJECTIVE: Otosclerosis is a disease of hereditary liability. It might be related to an autosomal dominant inheritance. The genetic penetrance is determined by multifactorial influences. This paper was designed to study the reasonable strategies for prevention and treatment of this disease. METHODS: A retrospective review derived from data of the management and follow-up of 14 cases in 6 families. According to the special pathological features of active phase of the otospongiosis, the suitable strategies for prevention and treatment of this disease were suggested. RESULTS: Diagnosis of 14 cases were confirmed by audiological, operative and/or pathological examinations. Eleven of fourteen cases underwent stapedectomy, in which 10 cases had the surgery on the ear with severer hearing loss, and one case on both sides. In all of the surgical cases, hearing levels improved significantly. Three cases have not yet received the stapedectomy, in which two cases scheduled for the surgery are currently treated by chondroitin sulfate and one case refused the surgical treatment due to financial shortage. CONCLUSION: Examination of the ear function at regular intervals (6-12 months) is recommended for the adults among the family members with high-incidence of otosclerosis. Audiological and radiological examination play an important role in early diagnosis and treatment. Attention should be paid to the medicine for management and prevention of this disease. Stapedectomy is an optimal choice for clinical otosclerosis not only due to its capacity to improve the hearing level but also to prevent the advance of hearing loss. Hearing aid is the suitable choice if stapedectomy is contraindicated.

Audiometry↗

[A novel method for screening anti-inner ear autoantibody in patients with autoimmune diseases].

OBJECTIVE: To appraise the clinical value of a newly established method, rapid electric field immobilizing liquid phase molecule dot blot analysis (REILMD), for screening anti-inner ear autoantibody in patients with autoimmune diseases. METHODS: Seventy-one patients with 11 kinds of autoimmune diseases were chosen for the study. Both the general immunity and autoantibodies were tested. In the processes of detection of anti-inner ear autoantibody, REILMD was used for screening, and then the Western blot was used to define the molecular weight of inner ear antigen recognized by the positive autoantibody. RESULTS: Acceleration of erythrocyte sedimentation rate (ES), positive rheumatoid factor (RF), increases in C reactive protein (CRP), IgG and circulating immune complex (CIC) were found in most cases with rheumatoid arthritis (RA) and systemic lupus erythematodes (SLE). Some of these patients had increased IgA, IgM and C4. Two of 16 RA had anti-double-stranded DNA (dsDNA) and anti-mitochondria and 4/16 had anti-nucleus antibodies. Eleven of 16 SLE had antinucleus, 7/13 had anti-ribonucleoprotein (RNP), anti-Sjögren syndrome A (SSA) and anti-dsDNA, 3/13 had anti-smooth muscle (Sm) and 1/13 had anti-DNA topoisomerase I (Scl)-70, striated muscle and stomach acid cell antibodies. No autoantibody was detected in AS. Anti-inner ear autoantibody existed in 9 out of 71 patients (13%) with autoimmune diseases, in 2 of 21 patients (10%) with sudden deafness and only in 1 of 48 control subjects (2%, coronary heart disease). The anti-inner ear autoantibody was positive in 5 of 16 (31%) patients with SLE and 1 each in RA, AS, Behset's disease and streptococcus infection syndrome. In patients with positive anti-inner ear antibody, 67% had anti-nucleus antibody, 50% had anti-RNP and dsDNA antibody. The molecules recognized by the positive anti-inner ear antibody were defined as 52,000, 36,000, 31,000 and 15,000 molecules of inner ear antigen. CONCLUSION: REILMD is a feasible and easy method for screening anti-inner ear autoantibody. Several autoimmune diseases, particularly SLE, may be implicated in damage to the inner ear.

Adolescent↗

[The electron microscopic study of AchR and ultrastructure of neuromuscular junction in recurrent laryngeal nerve reinnervation].

OBJECTIVE: The purpose of this study was to observe the distribution of Acetylcholine receptor (AchR) and ultrastructural changes of the neuromuscular junction after laryngeal reinnervation. METHODS: alpha-bungarotoxin-horseradish peroxidase (alpha-BT-HRP) conjugate electron microscopic immunocytochemical methods and computer analysis of intensity of immunocytochemical reaction were applied to observe the distribution and relative quantity of junctional N-AchR. RESULTS: The results showed that the synaptic nerve terminals and presynaptic membrane were segmentally disrupted and almost disappeared completely and were replaced by Schwann's cells at 3 weeks after neurorrhaphy. At 6 weeks, some of the regenerating axons grew to the neuromuscular junctions and all the muscle fibers were reinnervated at 12 weeks. But the original postsynaptic membranes were only partially in contact with the regenerated nerve terminals. These conditions persisted until 18 weeks after neurorrhaphy, when remyelination was found in the vicinity of the neuromuscular junctions. The N-AchR reaction product on the postsynaptic membrane were increased greatly about 1.28 times more than the normal at 3 weeks after neurorrhaphy. The reactive products decreased greatly which was only 0.47% of that in the normal at 6 weeks. It remained low until 12 weeks after neurorrhaphy, which was 0.72% of the normal side. It increased obviously to 0.83 times of normal sides at 18 weeks and didn't changed there after. CONCLUSION: The state of reinnervation determines the quantity of neuromuscular junctional N-AchR.

Animals↗

[Partial laryngectomy for T3 glottic carcinoma].

OBJECTIVE: To explore the possibility of partial laryngectomy for T3 glottic carcinoma and selection of reconstruction methods. METHODS: From January 1986 to January 1994, 78 patients with T3 glottic carcinomas were treated by partial laryngectomy. The operative techniques and the reconstruction methods were retrospectively analyzed. RESULTS: The overall 3 and 5 years survival rates were 88.5% and 75.6% respectively. The local recurrence rate was 15.4%. The reconstruction methods for laryngeal defect repariring following partial laryngectomy were the use of pyriform sinus mucosa with thyroid perichondrium, epiglottic cartilage and bi-pedicaled and bi-muscular flap of strap muscle. The function of respiration, phonation and deglutition recovered well. CONCLUSION: The partial laryngectomy is suitable for T3 glottic carcinoma. The selection of reconstruction method is based on the size of laryngeal defect.

Adult↗

[Supracricoid subtotal laryngectomy for the treatment of advanced laryngeal cancers].

OBJECTIVE: This procedure was designed to eradicate the advanced laryngeal carcinomas while preserving the laryngeal physiologic function. The indications and contraindications for the operation were also discussed and evaluated in this paper. METHODS: Twenty-one patients with advanced laryngeal cancers underwent this procedure during the period from 1988 through 1996 in our department. All of the patients were not amenable to conventional partial horizontal and vertical laryngectomies. In those patients, there were 9 supraglottic cancers, 10 glottic cancers and 2 transglottic cancers. Among them, 16 cases had stage T2 lesions and 5 cases had stage T3 lesions. In this procedure, the hyoid and thyroid cartilages were excised in toto, along with both true and false vocal cords, paraglottic space as well as the partial or total epiglottis and the whole preepiglottic space. The cricoid cartilage and at least one arytenoid cartilage were spared. The new larynx was reconstructed by suturing the cricoid and/or epiglottis to the base of the tongue. RESULTS: Of 21 patients, 95% were able to eat normally without aspiration, 90% were decannulated with near normal speech function. In two patients, the tracheotomy tube was reserved, one developed a stenosis, and another had recurrent aspiration pneumonia. No patients experienced local recurrence. Nineteen patients were followed up for at least 3 years, 13 patients achieved 5 years tumor-free survival. CONCLUSION: The term supracricoid subtotal laryngectomy best describes the surgical approach and the reconstruction model of the new larynx. As a useful alternative to total laryngectomy in selected advanced laryngeal cancers, this procedure may greatly improve the quality of life and prolong the life without recurrence.

Adult↗

[Surgical treatment of malignant esophageal tumors in PUMC Hospital].

OBJECTIVE: To study how to prolong the postoperative survival time of the patients with malignant esophageal tumors. METHODS: The clinical data of 1,098 patients with malignant esophageal tumors from 1961 to 1992 were retrospectively analyzed. The deletion of fragile histamine triplet(FHIT) gene(a tumor suppressor gene) in 30 fresh esophageal samples obtained in 1996 was detected with PCR and RT-PCR. RESULTS: The resectability was raised gradually and the operative morbidity and mortality decreased year-by-year, but there was no significant improvement on the postoperative 5-year survival rate. Delayed diagnosis and ir-radical resection influenced the long term survival. The deletion of cDNA of FHIT gene was 64.2% in esophageal cancer and 20% in the resected margin of the cancer. CONCLUSIONS: High atypical hyperplasia in esophageal epithelium and deletion of FHIT gene in esophageal cancer and its resected margin are pathological and molecular markers for early diagnosis of esophageal cancer respectively, and the latter may be one of the molecular markers for the resection. Early diagnosis and treatment, radical resection, and postoperative nutritional support are essential for the improvement of the postoperative survival time of the patients.

Acid Anhydride Hydrolases↗

[Expression of epidermal growth factor receptor in gestational trophoblastic tumours].

OBJECTIVE: To investigate the expression of epidermal growth factor receptor (EGFR) in gestational trophoblastic tumours and its clinical significance. METHODS: Placentas of 10 normal early pregnancies, 20 molar pregnancies, 10 samples from invasive mole and 8 samples of choriocarcinoma were used for the study. EGFR expression was evaluated by immunohistochemistry using monoclonal antibody. RESULTS: EGFR was expressed both in normal chorionic villi and tissues of trophoblastic tumours. EGFR was expressed more strongly in normal chorionic villi and non-malignant transformed hydatidiform mole than in malignant transformed molar pregnancies and malignant trophoblastic tumours (P < 0.05). Univariate and multivariate analysis indicated that EGFR immunostaining intensity was significantly related to the clinical stage in malignant trophoblastic tumours (P = 0.026, OR = 9.874). CONCLUSION: EGFR expression could be used as an index for prediction of malignant transformation of hydatidiform mole and staging of malignant trophoblastic tumours.

Adult↗

[Principle of evidence-based medicine and its application in clinical trial practice for glutamine and gut permeability].

Evidence-based medicine (EBM) was developed from the progress of traditional clinical model trial patterns. EBM was based on well-designed, randomized, double blind, controlled, multiple center trails in order to assess end pont parameters, prognosis parameters (as: mortality, morbidity of complications and hospital stay etc.), quality of life and cost/effect ratio. It has been accepted in developed countries and could be the guidelines for Chinese clinical trials in the future. This article summarized the principle of EBM and attached with a clinical trial sample about effects of glutamine dipeptide on gut barrier function, post-operative complications and the hospital stay.

Aged↗

[An experiment of gut barrier function damage following multiple firearm injuries in a porcine model].

OBJECTIVE: To study the characteristics and pathogenesis of gut barrier damage following multiple firearm injuries in porcine models. METHODS: 24 small pigs were divided into 4 groups (n = 6 each): control group(group C), group H (gunshot-induced tangential fracture of parietal bone), group L (gunshot-induced comminuted fracture of bilateral femora) and group M (combined group H + L). Gastric intramucosal pH (pHi), plasma endotoxin in portal vein, and plasma D-lactic acid were measured and blood samples were cultured at different time intervals after trauma. The animals were sacrificed at 72 h and ileum tissues were harvested for pathological examination and DAO measurement. RESULT: In group M at 72 h, pHi was significantly lower than that of group H and L(P < 0.01), plasma endotoxin level was significantly higher than that of group H(P < 0.01) and group L(P < 0.05), D-lactic acid level was significantly higher than that of group H(P < 0.01), and bacterial isolation rate in blood was much higher than that of group H and L(P < 0.05). Necrosis and peeling off were revealed at ileum villus top in all trauma groups, especially in group M, in which ileum DAO content also declined in most cases. CONCLUSION: Multiple traumas were prone to gastrointestinal ischemia even when hemorrhagic shock did not take place. The damage of gut barriers in multiple traumas were more severe than that in one-site trauma, which enhanced the incidence of intestinal endotoxin and bacterial translocation and trend to cause enterogenous infection.

Amine Oxidase (Copper-Containing)↗

An epidemiology and molecular genetic study on breast cancer susceptibility.

OBJECTIVES: To investigate the genetic susceptibility for breast cancer of Chinese, a hospital-based case-control study, pedigree survey and molecular genetic study were conducted. METHODS: Logistic regression model and stratification methods were used in the risk factors analysis. Li-Mantel-Gart and Falconer methods were used to analyse the segregation ratio and heritability. Polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis were used to detect AI, G-binding technique was used to detect the chromosome aberration of peripheral blood lymphocyte. RESULTS: Family history of breast cancer is related to enhanced breast cancer risk significantly, OR is 3.905 (95% CI = 1.079 approximately 14.13), and it widely interacts with other risk factors. Accumulative incidence of breast cancer in first degree relatives is 9.99%, which is larger than that in second, third degree and non-blood relatives. Segregation ratio is 0.021, heritability among first degree relatives is 35.6 +/- 5.8%. Frequencies of LOH at BRCA1 and BRCA2 loci in sporadic breast cancer are 6.12% and 5.77% respectively. In the sibs, both of them show LOH at D13S173 locus, and high frequencies of chromosome aberrations were observed. CONCLUSIONS: Genetic susceptibility contributes to breast cancer occurrence of Chinese, and its racial variation may be one of the important reasons for the large difference of incidence between western and eastern countries.

Adult↗

Adenosquamous lung carcinoma: clinical characteristics, surgical treament and prognosis.

OBJECTIVE: The effectiveness of surgical resection of adenosquamous carcinoma of the lung remains poorly defined because of the histology's relatively low frequency, the failure in most published series to separate adenosquamous carcinoma from the other variants of non-small cell lung carcinoma. To define the effectiveness of treatment of adenosquamous carcinoma, we have retrospectively reviewed our hospital experience over a 12-year period. METHODS: Retrospectively reviewed 22 cases of adenosquamous carcinoma who were surgically treated, except one patient, in the PUMCH from Jan. 1985 to Aug. 1997. This series constitutes the 1.9% of a total of 1 245 patients with all types of surgical treatment for the primary lung cancer during the same time. RESULTS: The adenosquanous carcinoma was mostly presented in the old patients with a mean age of 60 years and mostly located in the peripheral of lung (n = 20). The overall 5-year survival was 23%. Those with stage I tumors survival was only 18% (n = 13), stage II 5%. The survival in stage III tumos was not longer than 25 months and in stage IV survival was not longer than 12 months. CONCLUSION: Our results suggest that adenosquamous carcinoma of lung was a virulent tumor, which exhibited highly aggressive biological behavior with early lymph nodes metastasis (46%) and its prognosis was worse than that of both squamous cell carcinoma and adenocarcinoma.

Adult↗

[IR spectra and structures of two trinuclear molybdenum cluster compounds coordinated by binary carboxylates].

Two trinuclear molybdenum cluster compounds coordinated by binary carboxylates compounds Mo3S4 (DTP)3(phthalate) (Py)(A) and Mo3S4 (DTP)3(malonate)(Py)(B) have been synthesized. IR absorption peaks of Mo3S4 core and the ligands are assigned with reference to those of Mo3S4(DTP)4(Py)(C). The assignment of stretching vibrations of carboxylate (COO-) for both (A) and (B) reveals much information corresponding to their molecular structures.

English Abstract↗

[Effect of organic tin on the morphology and mechanical properties during polyurethane-urea curing process].

The mechanical properties and morphology of crosslined PUU in bulk quasi-prepolymer process was studied by in situ FTIR. From the quantitative change of carbonyl FTIR spectra, the development of morphology between noncatalyzed and catalyzed polymerization process was discussed in detail. The effect of organic tin concentration on the mechanical properties was investigated. It showed that urea carbonyl splitted many small weak bands at different sites with increasing of organic tin concentration, and the catalyst played an important role in controlling the morphology and mechanical properties. It also showed that the mechanical properties reached extreme value when the rate constant of -NCO/-OH reaction equate the rate constant of -NCO/-OH reaction.

Catalysis↗

[Data processing for interferogram of ultraviolet Fourier transform spectrometer].

The method of data processing for interferogram is described in this paper. The interferogram of a mercury lamp has been measured in experiment by means of ultraviolet Fourier Transform Spectrometer in developing. The apodization function that we have chosen is four-term Blackman-Harris window function and a fitting polynomial has been used for phase correction of Fourier Transform spectra based on the least square method. The ultraviolet emission lines of high precision have been obtained by use of this method.

Electronic Data Processing↗

[The effect of temperature on the structure and properties of polyurethane-urea by FTIR].

The effect of temperature on the structure and properties of polyurethane-urea was investigated by in situ FTIR. Data from FTIR spectra showed that with increasing temperature the nu NHHbonded areas decrease and the nu NHfree band areas increase. The band site of nu NHHbonded shifted to higher wavenumbers and the band site of nu NHfree keeps constant. The band site of Cfree urethane shift from 1,731 cm-1 to 1,736 cm-1. All kinds of carbonly bands sites shifted to high wavenumbers. But the band sites of amide II and the C=C in aromatic ring shifted to low wavenumbers. The properties of PUU polymers was determined by the structure of soft domains.

Polyurethanes↗