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Biomedical subjects

H Yang

Publications and source records attributed to H Yang.

At least 469 records · Page 26Linked to original sources
PubMed1999

[Logistic regression analysis of female drug abusers' social-psychological factors].

OBJECTIVE: To study the social-psychological health status on female drug abusers. METHODS: Case-control study and logistic regression analysis. RESULTS: Results of simple logistic regression showed that factors with significant ORs were low education level, unemployment, marital status, senseless of life, self-killing, horror, madness, depression, insomnia, dizziness, perspiration, evil dream, divorce, setbacks of emotion, smoking, alcohol-abuse, playing truant, runaway from home, fighting, etc. The results of stepwise logistic regression analysis showed that factors entered the regression model were smoking, runaway from home, divorce, setbacks of emotion, marital status, hopeless toward life, level of education, dizziness, etc. CONCLUSION: Most female drug abusers' social-psychological status was poorer than controls preceding to their drug abuse, which contributed to the major causes of abuse drugs.

Adolescent↗
PubMed1999

Mechanical stress regulation and proliferation of rat mandibular condylar chondrocytes in vitro.

OBJECTIVE: To study the proliferative changes of cultured rat mandibular condylar chondrocytes effected by mechanical stress. METHOD: Flow cytometry (FCM) was used to explore the changes of cellular DNA content and cell cycles of passaged condylar chondrocytes. RESULTS: FCM results indicated that proliferation of cultured rat mandibular condylar chondrocytes decreased with stress duration, with marked differences between the experimental and control groups. CONCLUSION: Within given force duration and force range (0-207 g/an2), proliferation of rat mandibular condylar chondrocytes increased with force magnitude, reaching the maximum 6 hours after application of stress. Cellular proliferation decreased when the chondrocytes were cultured under continuous stress for 24 hours. The mechanism for these proliferation changes requires further study.

Animals↗
PubMed1999

Interaction of tumor-infiltrating lymphocyte from oral squamous cell carcinoma with FN enhances its adhesion and cytotoxicity.

OBJECTIVE: To investigate the influence of fibronectin (FN) on cytotoxicity and adhesion of tumor-infiltrating lymphocytes (TIL) from oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: TIL cells were isolated from surgical specimens of 9 patients with OSCC. Specific cytotoxicity for autologous tumor cells were tested by 3H-TdR 4 hours release, and specific TNF-alpha release was detected using enzyme-linked immunosorbent assay. Expression of intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) on TIL cells were analyzed on FACScan following incubation with FITC-conjugated antibody. Cell adhesion ability was evaluated through detection by optical density (OD) values of bound cells and unbound cells. RESULTS: TIL-specific cytotoxic activity for autologous tumor was significantly enhanced, ranging from 17.7% to 67.6% by incubation on FN (P < 0.005). Cell adhesion was increased ranging from 42.5% to 62.7% by coculturing with FN (P < 0.005). The interaction of TIL with FN increased expression of ICAM-1 and LFA-1 on TIL cells as well. But specific TNF-alpha release was not obviously changed by FN (P > 0.5). CONCLUSION: The enhanced TIL activity by FN might be mediated by increased binding of TIL to targets through adhesion strengthening. This culture system would be useful to improve the TIL generation for cancer therapy.

Carcinoma, Squamous Cell↗
PubMed1999

[Treating women with gestational impaired glucose tolerance reduces adverse outcome of pregnancy].

OBJECTIVE: To study the treatment of women with gestational impared glucose tolerance (GIGT) in relation to outcome of fetus and newborns. METHODS: 98 women with GIGT were randomized into untreated (37 mothers) and treated groups (61 mothers) that included diet control and insulin therapy. The perinatal outcomes were compared in the two groups. RESULTS: The incidence of macrosomia (P < 0.01) and fetal distress (P < 0.05) was found to be significantly higher in the untreated group when compared with the treated group. The prevalence of neonatal metabolic complications in the untreated group was higher than that of the treated group as well. CONCLUSION: Treatment of women with GIGT will reduce adverse outcome in pregnancy.

Adult↗
PubMed1999

[Apoptosis and necrosis of neuron after focal ischemia in brain of rats].

This article reports the apoptosis and necrosis of neurons following ischemia-reperfusion in the brain of rats. The focal ischemia model was established by occluding the middle cerebral artery for 2 h and reperfusing for 0.5-48 h. The neuronal changes were investigated by HE staining, TUNEL and agarose gel-electrophoresis. The foci of ischemia were in the preoptic area, striatum and cortex. At 0.5 h of reperfusion, there were quite a few apoptotic neurons in the preoptic ischemic focus, but only a few scattered apoptotic cells were seen in the striatum and cortex. During 3-6 h of reperfusion, the number of apoptotic cells increased and the necrotic cells appeared. The number of apoptotic cells reached a peak at 12-24 h and the in morphology varied, and they were mainly located in the inner boundary of infarct. At 48 h, the apoptotic cells decreased; and the necrotic cells increased. Agarose gel-electrophoresis showed the dense smear and ladder pattern of DNA fragments, the apoptosis and necrosis of neurons coexisted, and apoptosis contributed to the enlargement of the ischemic infarct.

Animals↗
PubMed1999

Investigation of long-term preservation of pancreatic islets.

OBJECTIVE: To develop a method for maintaining viability and function of islets of Langerhans during the long-term preservation. METHODS: We encapsulated Wistar Furth (WF) rat islets in hydrophilic macrobeads (diameter 6-8 mm) made with agarose and collagen, then preserved them at 37 degrees C in a humidified atmosphere of air and 5% CO2 for different time, and compared unencapsulated islets with encapsulated islets for their insulin secretion capability in vitro. At the same time, we have investigated their viability and insulin secreting function in vivo. RESULTS: Initially, there was no statistically significant difference in the insulin secretion values between the encapsulated and unencapsulated WF rat islets. While the unencapsulated islet insulin secretion decreased significantly within 2 weeks, the preserved and encapsulated islets maintained their viability and ability of insulin secretion for 40 weeks. In the in vivo study, the diabetic state was reversed in 92.8% of recipients transplanted with preserved macroencapsulated islets. The mice maintained normoglycemia for 157.6 +/- 49.3 days, at which point these macrobeads were retrieved. Glucose tolerance curves in the recipient mice were similar to those of normal mice. CONCLUSIONS: These results indicate that it is a good method for long-term preservation of islets by encapsulating islets in agarose and collagen, and then culturing them at 37 degrees C in a humidified atmosphere of air and 5% CO2 before transplantation.

Animals↗
PubMed1999

[Treatment of invasive burn wound infection with sepsis: a clinical study].

OBJECTIVE: To further improve the treatment of burn wound sepsis. METHODS: Eight patients with burn wound sepsis, of whom 6 with MODS and two with septic shock, were treated consecutively in our hospital from September 1997 to October 1998. The plasma concentrations of IL-6, IL-8 TNF and LPS were assayed before and after surgical intervention and at the time when the patients' vital signs became stable. RESULTS: (1) The patients' conditions abruptly deteriorated when the burn wound sepsis emerged. (2) The major causative factor related to burn wound sepsis was extensive burn injuries, with large area of deep burn remained open. (3) Although colonization by multiple pathogenic bacteria was found, Pseudomonas aeruginosa was the most frequent bacteria isolated from the subeschar tissue. (4) The plasma concentrations of IL-6, IL-8, TNF and LPS before surgical intervention were significantly higher than those after surgical intervention (P < 0.05); (5) The lowest level of the inflammatory mediators were observed when the conditions of patients became stable, and the values were significantly lower compared with those before surgical intervention (P < 0.001). CONCLUSIONS: The main cause of burn wound sepsis is the presence of a large area of infected open deep burn wounds, which should be excised and covered early. LPS and pro-inflammatory mediators play an important role in the pathogenesis of burn wound sepsis. Favorable results in the treatment attribute to appropriate application of multiple treatments, and early, aggressive and thorough surgical excision of invasive burn infectious tissue and closure of wounds play a crucial role.

Adolescent↗
PubMed1999

A feasible and effective technique for the detection of Schistosoma japonicum cercaria-infested water.

OBJECTIVE: To develop a new technique for detecting Schistosoma japonicum (S. japonicum) cercariae so as to predict the distribution of area with high transmission potential and to control acute infection of schistosoma. METHODS: A C-6 film was established and used to adhere the cercariae on water surface and compared with a few other conventional detecting techniques. RESULTS: The average rate of the cercaria-recovery was 40% in laboratory and field using C-6 film, which was 20 times higher than that of traditional nylon-tissue adsorbing and precipitating method. Either in some areas where oncomelania were present or in some places where the snail had been under control, the technique could detect the cercariae. CONCLUSION: The technique can be characterized by a feasible, economical, promptly accessible method, especially for field application.

Animals↗
PubMed1999

[The relationship between sleep related breathing disorders and stroke].

OBJECTIVE: To study the relationship between sleep related breathing disorder(SRBD) and cerebrovascular diseases (CVD). METHODS: Polysomnographic studies on 43 cases of CVD were performed and 43 sex-, age-, body mass index- compatible cases without CVD used as controls. RESULTS: The incidence of SRBD (mostly the obstructive one) was much more in CVD patients and both the obstructive and central apnea/hypopnea indices, deoxygenation indices were bigger and deoxygenation time were longer while the mean and lowest oxygen saturation were lower in CVD group than those in the controls (all P < 0.05). The blood pressure before sleep, after awakening and the mean BP during sleep were also higher in the CVD patients. In CVD group, the incidence of hypertension was also much higher in SRBD patients than that in non-SRBD ones (P < 0.01). SRBD was dangerous for CVD as OR value was 6.28. CONCLUSIONS: SRBD may be one important risk factor for CVD. An vicious circle might be formed between stroke and SRBD which inflences the outcome of stroke.

Blood Pressure↗
PubMed1999

[Experimental condition for WST-1 assay of skin viability].

OBJECTIVE: To investigate a new tetrazoliium salt assay (WST-1) of detecting tissue and cells of preserved skin. METHODS: With WST-1, viability of porcine and human skin split were assessed. The experimental condition such as dosage of agents, thickness of skin split, time of reaction, area of skin split and weight of skin split were determined. RESULTS: Optimal experimental condition of skin split should be 10 mm diameter and 0.3 mm thick, incubation for 3 hours at 37 degrees C, and reagent dosage of 20 microl. CONCLUSIONS: As a reagent for detecting cell viability, WST-1 is successfully applied to the assessment of skin viability.

Animals↗
PubMed1999

[Biomechanical evaluation of five fixation techniques for the lower cervical spine].

OBJECTIVE: This study biomechanically investigated the three-dimensional motion stability of five reconstruction methods in the cervical spine, in order to provide the biomechanical basis for the clinical selection of fixation methods. METHODS: With eight adult cervical spine fresh specimens, the three-column injury was produced at C(4 - 5) level. The spinal constructs, reconstructed by various techniques including anterior titanium locking screw plate (TLSP), posterior interspinous wiring (IW), combined fixation with the TLSP and IW (TLSP + IW), Roy-Camille plate (RP), and transpedicular screw plate (TP), were tested under six loading modes-flexion, extension, right/left lateral bending, and right/left axial rotation. RESULTS: The three-dimensional motion stability of either TLSP or IW was less than that of intact cervical spine. The TLSP + IW and RP provided increased stability compared with the intact spine. The stabilizing capabilities of transpedicular screw plate fixation was the best in all loading modes. CONCLUSIONS: In three-column instability of cervical spine injury, exclusive use of the anterior plate or the posterior interspinous wiring was not supported by the results. The stabilizing capabilities provided by combined anterior and posterior instrumentation and posterior plate were good. The three-column fixation for the cervical spine using transpedicular screw plate fixation offers increased stability significantly over that of other conventional cervical fixation systems.

Adult↗
PubMed1999

[Transcatheter arterial embolization of renal carcinoma with absolute ethanol].

OBJECTIVE: To study transcatheter arterial embolization (TAE) of renal carcinoma using absolute ethanol so as to reduce bleeding for a higher resection rate, as a palliative treatment for advanced renal carcinoma. METHODS: Using Seldinger method, we treated 25 cases of renal carcinoma with transcatheter arterial embolization. RESULTS: The average bleeding of 25 cases during nephrectomy was 210ml after TAE. There was no mortality and serious complication. But there was pain and fever in most cases. CONCLUSIONS: TAE with absolute ethanol is an effective, safe and easy procedure. It could be used as an adjuvant therapy for renal carcinoma.

Adult↗
PubMed1999

[A clinicopathological study of 297 cases of retinoblastoma].

OBJECTIVE: To find a morphological criterion of classification for choroidal invasion of retinoblastoma in order to further study clinical pathology of retinoblastoma (Rb) under an integrate rule. METHODS: The changes of retinal pigment epithelium, Bruch's membrane and choroid on histopathological sections of primarily enucleated eyes with Rb in 297 cases were observed under a light microscope. RESULTS: The globe wall invasion could be morphologically divided into four stages (briefly pigment epithelium-choroid classification). Stage I: Only retinal pigment epithelium was infiltrated, the Bruch's membrane was intact. Stage 2.: The Bruch's membrane was destructed, but the choriocapillaries were not invaded. Stage 3: The invasion reached middle choroidal blood vessels close to the choriocapillaris in a limited scope. Stage 4: Massive choroidal infiltration of all choroidal layers existed and the sclera could be simultaneously involved. The mortality for stage 4 was 11.5% and for stage 1 to 3 was 0.4%. CONCLUSION: The pigment epithelium-choroid stage (PEC-stage) classification in our study can be used as an integrate rule to compare the invasion degree of retinoblastoma in different individuals and studies.

Adolescent↗
PubMed1999

[Determination of serum calicotonin gene-related peptide in patients with duodenal ulcer infected with Helicobacter pylori].

OBJECTIVE: To investigate the effect of calicotonin gene-related peptide(CGRP) on duodenal ulcer caused by Helicobacter pylori infection. METHOD: The serum levels of CGRP were determined by radioimmunoassay in 30 patients with duodenal ulcer associated with Helicobacter pylori infection and 20 healthy volunteers. RESULTS: The mean CGRP serum level was higher in duodenal ulcer associated with Helicobacter pylori group than that in the healthy group. CONCLUSION: The CGRP level might be one of the important factors in which Helicobacter pylori infections induce duodenal ulcer.

Adult↗
PubMed1999

[Determination of inorganic arsenic in food by hybrid generation-atomic fluorescence spectrometry (HG-AFS)].

A hybrid generation-atomic fluorescence spectrometry method (HG-AFS) was developed for determining total inorganic arsenic, As(III) and As(V). The inorganic arsenic in food extracted by 6 mol/L HCl and total inorganic arsenic could be determined in 2 mol/L HCl. As(III) was determined selectively in mixtures of As(III) with As(V) by the different acidities of As(III) and As(V) at hybrid generation. The linear correlation ranges of total inorganic arsenic and As(III) are 0-400 micrograms/ml and 0-300 micrograms/ml respectively. The RSD of inorganic arsenic is 1.93% and As(III) is 2.49%. The detection limits are 1.6 and 1.1 micrograms/ml for inorganic arsenic and As(III) respectively. There is no interference in the determination of general food samples.

Arsenic↗
PubMed1999

[Apoptosis of CD4(+) T cells during experimental autoimmune neuritis in Wistar rats].

The present study describes apoptosis of T cells in the sciatic nerve in Wistar rats with experimental autoimmune neuritis(EAN). Morphological characterizations of apoptosis were found at the 18th day from onset, peaked at the 22nd day by immunocytochemical analysis. In situ end labeling(ISEL) techniques confirmed the presence of DNA fragmentation in CD4(+) T cells. It is suggested that apoptosis is an important clearance mechanism of infiltrated T cells in the peripheral nervous system(PNS) in EAN.

Animals↗
PubMed1999

[The behaviour of rat mandibular condylar cartilage in cell culture].

This study aimed to identify the behaviour of mandibular condylar chondrocytes in vitro. Cells were harvested from the mandibular condyles of 3 week-old S. D. rats. Cell structure, morphology and characteristics were assessed by phase-contrast microscopy, scanning electron microscopy, enzymohistochemistry and immunohistochemistry. The cultured condylar chondrocytes, stellated or spindle-shaped, could grow in several layers and form many cell colonies. They could secret proteoglycans, alkaline phosphatase, type II collagen, et al. The methods of isolation, culture and identification of condylar chondrocytes were presented and discussed, which can be adopted in probing further into the cellular mechanism of functional orthopedics.

Animals↗