Biomedical subjects

Z Li

Publications and source records attributed to Z Li.

At least 775 records · Page 43Linked to original sources

PubMed1999

[Effects of hyperbaric oxygen therapy on the changes in serum sIL-2R and Fn in severe burn patients].

OBJECTIVE: Many reports showed that level of soluble interleukin 2 receptor (sIL-2R) in sera was obviously increased in burn patients, while plasma fibronectin (Fn) was markedly decreased, and they had close relation with the occurrence and development of burn infection. The purpose of this study was to verify the significance of hyperbaric oxygen therapy (HBOT) in the prevention and treatment of burn infections by observing its effect on the levels of serum sIL-2R and Fn in severe burn patients. METHODS: Forty two burn patients(with more than 30% body surface area or three degree more than 10%) were selected and divided into two groups at random: HBOT group(25 cases) and non-HBOT group(17 cases); forty healthy blood donors were selected as normal control. The venous blood samples were drawn from 42 patients at 1/3, 1, 2, 3, 5, 7, 10, 14, 17, 21, 28 and 35 days postburn, the levels of serum sIL-2R and Fn were measured by ELISA and rocket electrophoresis techniques respectively, meanwhile, the incidences of sepsis of two groups were compared. RESULTS: 1. In non-HBOT group: the levels of serum sIL-2R were remarkably increased, while serum Fn were markedly decreased at all periods postburn (compared with normal control: P < 0.05 or P < 0.01); 2. In HBOT group: the levels of serum sIL-2R were not obviously increased at all periods except 21 days postburn, and Fn were not decreased at all periods except 8 h postburn (compared with normal control: P > 0.05). Compared with non-HBOT group, however, the levels of serum sIL-2R were profoundly reduced, while Fn was significantly enhanced at all periods postburn(P < 0.05 or P < 0.01), and the incidence of sepsis was obviously lowered (P < 0.05). CONCLUSION: HBOT can significantly reduce the level of serum sIL-2R but enhance Fn in severe burn patients, so it may have a positive effect on the prevention and treatment of burn infections.

Adolescent↗

PubMed1999

Corneal topographic analysis after excimer photorefractive keratectomy.

OBJECTIVE: To evaluate the corneal surface changes and visual quality after excimer photorefractive keratectomy (PRK) for myopia. METHODS: Corneal topographic analysis was performed on 23 patients (38 eyes) with myopia after PRK at the 1-, 3-, 6- month postoperative follow-up visits. RESULTS: The corneal sphericity was changed after excimer PRK. As time went on, the mean surface regularity index (SRI) and the surface asymmetry index (SAI) decreased gradually, and the corneal surface became more smooth; mean simulated keratoscope readings (SimK) showed a gradual restoration. At the 6-month postoperative examination, corneal topography showed four main patterns of ablation: round or oblong (50%), collar-button (23.68%), semicircular (18.42%) and central island (7.9%). Patterns of ablation were correlated with visual acuity. CONCLUSION: The quantitative analysis of corneal topography is essential for evaluating corneal surface changes after PRK and helpful in the surgical design of PRK and in predicting the refractive outcome with greater precision.

Adolescent↗

PubMed1999

Ultrasound biomicroscopic study on changes of ocular anterior segment structure after topical application of cycloplegia.

OBJECTIVES: To observe the changes of the ocular anterior segment structure and the relationship between the intraocular pressure (IOP) and these changes after the topical application of cycloplegia using ultrasound biomicroscope (UBM), especially to observe the changes of ciliary body thickness, ciliary process thickness and ciliary process-lens distance. METHODS: The quantitative measurement with UBM and the measurement of IOP were performed before and after the topical application of 2% homatropine solution in 48 normal eyes. The results were statistically analyzed. RESULTS: In the parameters showing the changes of the anterior chamber angle after topical use of 2% homatropine solution, both the trabecular iris angle and the angle opening distance 250 decreased. The iris thickness 1 increased. The anterior chamber became deeper and the iris-lens contact distance became shorter. All these differences were statistically significant (P < 0.05). In the parameters showing the changes of ciliary body, the ciliary body thickness and the ciliary process thickness decreased. The scleral ciliary body angle increased. The iris-zonule distance decreased and the ciliary process-lens distance increased. All these differences were statistically significant (P < 0.05). The IOP increased from 17.63 +/- 3.45 mm Hg to 18.23 +/- 3.53 mm Hg after topical use of 2% homatropine solution, but the difference was not statistically significant (P > 0.05). CONCLUSIONS: After the topical use of cycloplegia, the anterior chamber becomes deeper. The anterior chamber angle becomes narrower, and the ciliary body becomes thinner and moves backward and the ciliary process-lens distance increases. By using UBM the structures of the ocular anterior segment in the living state can be observed and measured quantitatively. The ultrasound biomicroscopic imaging has its advantages in the morphological study of the ocular anterior segment.

Adult↗

PubMed1999

Circumferential resection and "Z"-shape plastic end-to-end anastomosis of canine trachea.

OBJECTIVE: To prevent anastomotic stricture of the trachea. METHODS: Forty young mongrel dogs, weighing 5-7 kg, were randomly divided into two groups: experimental group and control group, with 20 dogs in each group. Four tracheal rings were removed from each dog. In the experimental group, two "Z"-shape tracheoplastic anastomoses were performed on each dog, one on the anterior wall and the other on the membranous part of the trachea. In the control group, each dog received only simple end-to-end anastomosis. Vicryl 3-0 absorbable suture and OB fibrin glue were used for both groups. All dogs were killed when their body weight doubled. RESULTS: The average sagittal stenotic ratio were 1.20 +/- 0.12 for the experimental group and 0.83 +/- 0.05 for the control group. The average cross-sectional area stenotic ratio were 0.90 +/- 0.12 and 0.69 +/- 0.09 and T values were 8.71 and 4.57 for the two groups (P < 0.01). CONCLUSION: "Z"-shape tracheoplasty is superior to simple end-to-end anastomosis in preventing anastomotic stricture of canine trachea.

Anastomosis, Surgical↗

PubMed1999

[Experiences of early management of mass burn casualties].

OBJECTIVE: Inquire into the effective method of treatment to mass burn casualties. METHODS: The experiences of 22 batches of mass burns (403 cases) were reviewed. RESULTS: 1. The receiving hospital should take effective measures for initial care, and report to the higher health department. 2. Health department should send additional specialists to the hospital if necessary, and a leader should be appointed. 3. Ambulances with special pass or helicopter should be deployed to ensure dispatch of the helpers. 4. Emphasis on local hospital's initial treatments, including fluid resuscitation, establishment of an adequate airway, early wound management to prevent and premature dissolution of eschar. 5. Proper triage of patients, and severe burn patients should be hospitalized to burn units with adequate facilities. 6. Transportation: Patients can be transferred along where there are good transportation facilities, with fluid resuscitation, on the other hand, when transportation if poorly developed, transfer the patients after fluid resuscitation until the general condition becomes stable. CONCLUSION: 1. Mass burn casualties can be handled with satisfactory results if emergency care and professional treatment are well organized. 2. Mass burn casualties are usually caused by human errors, therefore they can be prevented.

Accidents, Occupational↗

PubMed1999

[Direct genotyping of an hereditary persistence of fetal hemoglobin deletion and rapid prenatal diagnosis of the fetus at-risk for compound heterozygote of this defect with beta-thalassemia in a Chinese family].

OBJECTIVE: To investigate the relationship between genotype and phenotype of a deletional hereditary persistence of fetal hemoglobin(HPFH) found in a Chinese family and explore an approach to rapid prenatal diagnosis for compound heterozygote of HPFH defects with beta-thalassemia. METHODS: By using the PCR-based method with three primers bridging a HPFH breakpoint and reverse dot blot (RDB) for detecting beta-thalassemia mutations, a Chinese family who had a propositus of six years old with intermediate thalassemia and requested prenatal diagnosis for the second pregnancy were screened. RESULTS: The propositus carried the HPFH deletion determinant inherited from her mother, and a codons 14-15 (+G) frameshift mutation causing beta-thalassemia from her father. Of six members in this family screened for this type of HPFH deletion, four were positive. Prenatal diagnosis of the fetus showed the same results as that of the propositus. An advice of termination of pregnancy was given and the result of prenatal diagnosis was confirmed in the DNA samples obtained after abortion. CONCLUSIONS: This is the first time to have performed prenatal diagnosis of Chinese family at-risk for compound heterozygotes for beta-thalassemia and HPFH in mainland China. The PCR assay for directly detecting the HPFH deletion is rapid and inexpensive and can be used as a routine in HPFH carrier screening and prenatal diagnosis.

Adult↗

PubMed1999

[The effect of thrombin on tissue factor activity in cultured bovine aortic endothelial cells and its correlation with PKC pathway].

OBJECTIVE: To study the stimulating effect of thrombin on the expression of tissue factor (TF) activity in cultured bovine aortic endothelial cells (BAEC) and to elucidate if it is associated with the PKC system. METHODS: The BAECs were cultured after the Schwartz's method and one stage clotting time assay was used to measure TF activity in BAEC lysates. The TF activity was identified by EDGR-VIIa and a monoclonal antibody against TF. RESULTS: Thrombin enhanced the expression of TF activity in cultured BAEC and the effect was dose- (r = 0.78, P < 0.05, n = 8) and time-dependent (r = 0.88, P < 0.05, n = 8). PMA, a PKC activator, also induced the expression of TF activity in BAEC. H7, a protein kinase C inhibitor, inhibited the inductive effects of PMA and thrombin on TF in BAEC. CONCLUSION: Thrombin can induce the expression of TF activity in cultured BAEC and the effect depends on PKC pathway.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

PubMed1999

Congenital choledochal cyst with pancreatitis.

OBJECTIVE: To understand the relationship among congenital choledochal cyst, anomalous junction of pancreaticobiliary duct (AJPBD) and pancreatitis. METHODS: 25 children with choledochal cyst treated in our hospital were included in this study. Their ages ranged from 2 months to 14 years. Intraoperative cholangiography was performed in 24 children. Pancreatic samples obtained from the head and body of the pancreas at operation were observed under light and electron microscope. Serum amylase was analyzed one week before and after operation respectively. Bile amylase in the cyst and gallbladder was measured at operation. RESULTS: The incidence of AJPBD was 70%. Inflammatory cell infiltration and fibrous hyperplasia were seen in the pancreatic specimens of 5 children, of whom 4 had AJPBD. No ultrastructural changes were found in 2 children without AJPBD, while different changes were seen in 6 with AJPBD, including those showing no pathological changes under light microscope. All the changes became more severe as the age of the patient increased. The bile and serum amylase levels were higher in children with AJPBD than those without AJPBD (P < 0.05). CONCLUSION: Congenital choledochal cyst has a close relationship with AJPBD and pancreatitis. Pancreatic pathological changes have a long and chronic course from ultrastructural changes to macroscopic changes for the developing of pancreatitis.

Adolescent↗

PubMed1999

[Discussions on acute pharyngo - laryngeal diseases treated with acupuncture by physicians of successive ages].

Originated from Neijing, the acupuncture treatment for acute pharyngo-laryngeal diseases was applied by Zhang Zhongjing under the guidance of Neijing and many acupuncture treatments for the disorders were mentioned by Huangfu Mi in his first monograph on acupuncture- moxibustion. Sun Simiao of the Tang dynasty further developed this technique and different therapeutic styles were developed by the Four Schools of Jinyuan dynasties. It was further supplemented by Yang Jizhou and Xue Ji of the Ming dynasty, and the scope of acupuncture treatment was further expanded by Zheng Meijian with disciplinary features and therapeutic mechanism. All the above descriptions from successive ages further pushed forward the development in this field.

Acupuncture Therapy↗

PubMed1999

[A historical review of the study of electrical activity of heart and origination of electrocardiography].

This paper has an overall review of the historical process of electrocardiographic development and the origination of modern electrocardiography in retrospect and also has an analysis of the scientific background, the important events and the historical effect of outstanding figures throughout the development. The experience and laws contained in the historical development are briefly summerized in this paper. At the same time the authors point out that the establishment of modern electrocardiography and the related technical development are crystallization of the wisdom and the result of the hard work of many scientists including the figures who should have been awarded Nobel Prizes.

Biophysics↗

PubMed1999

Blocking effect of puerarin on calcium channel in isolated guinea pig ventricular myocytes.

OBJECTIVE: To identify whether Puerarin (Puer) has blocking effects on L-type calcium channel. METHODS: We used whole-cell recording of patch-clamp techniques to analyse calcium channel current in ventricular myocytes isolated from Langendorff guinea pig hearts by collagenase. RESULTS: In control group, peak calcium channel current was decreased by 10.6% and 29.8% at 5, 10 min of recording time, respectively. For the same period, 0.1 mmol/L Puer reduced calcium current by 23.9% and 72.4%. 0.1 and 1 mmol/L Puer inhibited the amplitude of peak Calcium channel current by 40.6% and 63.2% after perfusing for 10 min. Compared with control group in which "rundown" phenomenon was observed, Puer also demonstrated its blocking effect on L-type channel. While washout of Puer with perfusing solution, calcium channel current went down further instead of recovery. Current-voltage (I-V) curves showed that the levels of calcium channel current were obviously decreased by Puer (both 0.1 mmo/L and 1 mmo/L) form -40 mV to +10 mV. CONCLUSION: Puer has blocking effect on L-type calcium channel in a concentration dependent manner.

Animals↗

PubMed1999

Subclasses of warm autoantibody IgG in patients with autoimmune hemolytic anemia and their clinical implications.

OBJECTIVE: To explore the mechanism of autoimmune hemolysis and establish a more sensitive test for autoimmune hemolytic anemia (AIHA). METHODS: IgG subclasses were tested in 40 patients with idiopathic or secondary AIHA by Coombs test with monoclonal antibodies. Hb, TBil, RC and FHb, as hemolytic parameters, were used to analyze the clinical implications of subclasses of AIHA warm autoantibody IgG. RESULTS: In most patients IgG incomplete warm autoantibody was IgG1 (27 patients), but IgG3 (20 patients), rarely IgG2 (14 patients) and IgG4 (9 patients) also occurred. Three groups were analyzed: Group A included 20 patients with IgG3; Group B included 14 patients with IgG1 bit without IgG3; Group C included 6 patients without IgG1 and IgG3. There were significant differences (P < 0.01) between groups in Hb, TBil, RC and FHb. Moreover, we also found that the sensitivity of Coombs test with polyclonal antiserums was 90.0%, while that of Coombs test with monoclonal antibodies was 97.5%. The effect of treatment was worst in patients with positive IgG3 autoantibody, whose hemolysis recurred frequently. CONCLUSION: IgG3 autoantibody was the most effective in bringing about red cell destruction, IgG1 autoantibody was less effective, IgG2 even less, whereas IgG4 autoantibody was shown to hardly affect red cell survival. Coombs test with monoclonal antibodies was more sensitive than that with polyclonal antiserums. Patients' respondence to treatment correlated with the type of IgG subclasses.

Adult↗

PubMed1999

Epstein-Barr virus infection in nasopharyngeal lymphoid hyperplasia.

OBJECTIVE: To detect whether Epstein-Barr virus (EBV) harbors in nasopharyngeal lymphoid hyperplasia (NPLH) which is frequently to be seen in Guangzhou, a high-incidence area of nasopharyngeal carcinoma (NPC), and to explore the relation between NPLH and development of NPC. METHODS: Twenty-four 10% formalin-fixed, paraffin-embedded biopsies oef patients with NPLH and elevated serum IgA antibody titer (> or = 1:20) against viral capsid antigen of EB virus (IgA/VCA) were collected from the archives of the Department of Pathology, Sun Yat-sen University of Medical Sciences during the period of January to June, 1993. PCR plus Southern blotting hybridization for detection of EBV DNA W-fragment and in situ hybridization for detection of EB virus encoded small RNAs (EBERs) were performed. All the patients were followed up more than 5 years. RESULTS: Twenty-two of 24 (91.7%) NPLH tissues contained EBV DNA. A few definitely EBERs positive B-lymphocytes could be found in 17 out of 24 specimens (70.8%). Neither NPC nor any EBV-associated malignancies were developed in all of these 24 patients up to date. CONCLUSION: Most of the NPLH tissues taken from the patients with an elevated serum IgA/VCA titer carry EBV, which is harbouring in the nuclei of a few infiltrating and hyperplastic B-lymphocytes. The NPLH without epithelial dysplasia can not be recognized as a precancerous lesion, and EBV infection in these lesions is not an important event, having no substantial significance in development of NPC.

Capsid↗

PubMed1999

[Changes of the activities of ET-1 in the serum and BALF of ILD patients and their clinical significance].

OBJECTIVE: To evaluate the roles of the Endothelin-1 (ET-1) in pathogenesis of the patients with interstitial lung disease (ILD). METHODS: The ET-1 activities in the serum and BALF from 10 patients with sarcoidosis, 7 with idiopathic pulmonary fibrosis (IPF) and 8 normal subjects non-smokers were determined using the radio-immunoassay. RESULTS: In the activities of ET-1 in the serum and BALF in the patients with sarcoiosis (62 +/- 29 and 17.0 +/- 2.4) ng/L and in the IPF (77 +/- 71 and 10 +/- 3) ng/L. was higher than those in the normal control subjects (20 +/- 8 and 4.0 +/- 0.6) ng/L. The activities of ET-1 in serum was negative correlated with PaO2 (r = -0.538, P < 0.01). The level of ET-1 in the BALF of the patient was positive correlated with total cells in BALF (r = 0.649, P < 0.01). The levels of ET-1 in the BALF in the sarcoidosis was positive correlated with the percentage of lymphocyte (r = 0.712, P < 0.01) but in patients with IPF was positive correlated with the percentage of neutrophil (r = 0.813, P < 0.01). CONCLUSIONS: ET-1 might play an important role in pathogenic of the patients with sarcoidosis and IPF. The levels of ET-1 can act as the markers of activity of disease.

Adult↗

PubMed1999

[Effect of pneumothorax on membrane diffusing capacity and pulmonary capillary blood volume].

OBJECTIVE: Investigating the effect of pulmonary membrane diffusing capacity(Dm) and pulmonary capillary blood volume(Vc) on carbon monoxide diffusing capacity (DLCO) in patients with pneumothorax before and after treatment, and clarifying the mechanism of hypoxemia due to pulmonary reexpansion. METHODS: Pulmonary function test, DLCO, Dm, Vc and arterial blood gas analysis were determined in 21 cases of pneumothorax before treatment and one week after pulmonary reexpansion. RESULTS: DLCO, Dm, Vc, partial pressure of arterial oxygen (PaO2), alveolar ventilation volume (VA), percentage of forced expiratory volume in one second to predicted value, and the ratio of dead space ventilation (VD) to tidal volume (VT) [VD/VT] were (64 +/- 4)%, (66 +/- 5)%, (70 +/- 5)%, (83.7 +/- 2.3) mm Hg, (4.4 +/- 0.2) L, (59 +/- 4)%, 0.340 +/- 0.020 respectively before treatment. After pulmonary reexpansion, they respectively were (71 +/- 4)%, (74 +/- 4)%, (80 +/- 6)%, (89.4 +/- 1.5) mm Hg, (5.40 +/- 0.20) L, (79 +/- 4)%, 0.210 +/- 0.010. They were significantly improved after treatment. Except for Dm, they were statistically different. Between Dm, Vc and DLCO, significant positive correlations were found during pneumothorax and one week after pulmonary reexpansion, especially correlation between Dm and DLCO was more apparent. Between Dm and DLCO significant positive correlations (r2 = 0.862, P < 0.0001; r2 = 0.728, P < 0.001) were found in study patients before and after treatment. So were Vc and DLCO (r1 = 0.643, P < 0.01; r2 = 0.52, P < 0.05). The correlation coefficient of Dm was markedly larger than Vc. CONCLUSIONS: The decrease in pulmonary diffusing function is related to Dm and Vc during pneumothorax, while decrease of Dm plays a major role. The hypoxemia is still presented in a period of time after pulmonary reexpansion, which is not related to VA and abnormality of ventilation-perfusion ratio (V/Q). It is chiefly due to unrecovery of Dm.

Adolescent↗

PubMed1999

[The role of surgery in the management of thyroid lymphoma].

OBJECTIVE: To evaluate the role of surgery in the management of thyroid lymphoma. METHODS: A retrospective analysis was performed of 14 patients with thyroid lymphoma treated at the Cancer Hospital, Peking Union Medical College, Chinese Academy Medical Science from 1964 to March 1998. There were 5 males and 9 females, with a median age of 54 years (range 15-75). There were 4 cases in stage IEA, 9 in stage IIEA, 1 in stage II EB. Fine needle aspiration biopsy was performed in 1 case, excision biopsy in 4, thyroid lobectomy in 8, and total thyroidectomy in 1. Radiotherapy was used alone in 4 patients, chemotherapy alone in 2, radiotherapy combined with chemotherapy in 7, no postoperative treatment in 1. RESULTS: All but 1 patients were histopathologically diagnosed as non-Hodgkin's lymphoma. It was of B cell origin in 11 cases, T cell origin in 2. Seven patients were alive without evidence of recurrent disease at follow-up, ranging from 5 to 112 months. Three patients died of lymphoma, 1 died of treatment complication, 2 died of other diseases, and 1 lost from follow-up. The major surgical resection did not appreciably affect survival. CONCLUSION: Radiotherapy or chemotherapy, alone or in combination, is the treatment of choice for thyroid lymphoma. Surgical resection combined with radiotherapy or chemotherapy may be beneficial to survival in patients with intrathyroid lymphoma. It is otherwise limited to make a tissue diagnosis.

Adolescent↗

PubMed1999

[A study of dental cast by using 3D laser non-contact measurement and analysis].

OBJECTIVE: To research and develop a new scanning 3-D digitization system for noncontact measuring of dental cast. METHODS: By using two pulsate motor to make the synthetic movement of the dental cast, a special semiconductor laser and two special line-array CCD, the 3D coordinate could be gotten from the surface of the dental cast in any where. The program which is developed by Visual C++ language and run under the Windows surroundings can control the scanner, rebuild the 3D graphics and measure the coordinate of the dental cast. RESULTS: The system offers 70 mm x 70 mm x 70 mm measurement scope, 0.01 mm resoling power < 0.1 mm mean deviation, 25 mins for single cast scanning. CONCLUSION: This system provides many advantages such as in precision, simplicity, high efficiency, and wide range of measurement contents with complete direct view. It also supplied us some new functions which can not be done with traditional way of measurement.

Dental Casting Technique↗

PubMed1999

[Surgical reduction of condylar fracture using lag screw].

OBJECTIVE: To evaluate the feasibility and result of application of lag screw osteosynthesis in condylar fracture. METHODS: Six dislocated condylar fractures were treated with lag screw. Postoperative follow-up mean 7 months (range 3-13 months). RESULTS: It showed no complaint on TMJ area from patients during the follow up, no facial asymmetry was found, no patient had malocclusion, 5 patients had mouth opening over 40 mm 3 months postoperatively, and all patients were satisfied with the treatment results. CONCLUSION: Based on the clinical and radiological results the authers believe that lag screw technique is a feasible method for indicated condylar fracture.

Adult↗