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Biomedical subjects

G Zhang

Publications and source records attributed to G Zhang.

At least 451 records · Page 25Linked to original sources
PubMed1997

[Studies on the mechanism of protection of cultured neurous by ketamine anoxia/reoxygenation-induced injury].

The effects of anoxia/reoxygenation (A/R) and glutamate on cultured cortical neurons from 16 to 18-day-old fetal rats and the protective effect of ketamine were studied. The 12-day cultures of 12 days were exposed to anoxia (5 h) followed by reoxygenation (0-24 h). Following progressive A/R, the release of lactate dehydrogenase (LDH) into the bathing medium obviously increased and exogenous glutamate (3 h) also markedly increased the release of LDH. When the cultures were pretreated with ketamine before A/R, the amounts of LDH efflux in culture medium were significantly less than those of controls. These results demonstrate that the cultured cortical neurons are seriously damaged by A/R and exogenous glutamate. Such damage could be attenuated by ketamine, suggesting that the neurotoxic effect of glutamate and NMDA (N-methyl-D-aspartate) receptors play an important role in the process of ischemia-induced damage in the brain.

Animals↗
PubMed1997

[Comparison of plasma thyroxin and insulin concentrations between 10-day old layer and broiler chickens].

In this study both sexes of 10 day old layer and broiler chickens were used to investigate plasma circulating concentrations of 3,3'-5-triiodothyronine (T3), thyroxine (T4) and insulin by using the radioimmunoassay (RIA) methods. The results were as follows: serum T3 concentration was higher in broilers than that in layers (P < 0.01), especially a significant difference between male strains was seen in this experiment (P < 0.001), and the levels of plasma insulin was significantly higher in male broilers than that in male layers (P < 0.001), however, no clear differences in plasma T4 was seen between strains and sexes (P > 0.05). In addition, there were sex differences in T3 and insulin levels in layers, that is to say, those in the female layers was higher than those in the male layers, but no clear deifference was seen between sexes in broilers. A significant positive correlation between T3, insulin and their weight gained (P < 0.05). The results suggest that the levels of serum T3 and Insulin may influence the various growth rate during early posthatch development in layers and broilers.

Animals↗
PubMed1997

[Effect of hypoxia on maximal myocardial blood flow in right ventricle].

In order to study the changes of coronary reserve capacity, the effects of hypoxia on hemodynamics and maximal myocardial blood flow in right ventricle were observed. Rats wre divided into 3 groups:normoxic group (control), acute hypoxic group and chronic hypoxic group. Maxmimal myocardial blood flow in the right ventricle was measured with 99 m Tc radiolabelled from RBC during adenosine infusion. The results showed that cardiac output, PaO2 and oxygen delivery were decreased during acute hypoxia, but myocardial blood flow in right ventricle was increased, as compared with the control group. There were no significant change of maximal myocardial blood flow in the right ventricle in acute hypoxic rats. Hematocrit and blood viscosity at different shear rate and RV weight index were augmented, whereas oxygen delivery and myocardial blood flow became normal during chronic hypoxia. Maximal blood flow in RV was significantly decreased whereas arterial wall thickness and collagen in arterial adventitia were increased in chronic hypoxic rats. The above results suggest that the decreased coronary reserve might beresulted from the increasedblood viscosity, arterial wall thickness and collagen in arterial adventitia and right ventricular hypertrophy.

Animals↗
PubMed1997

[Studies of mechanism of erythrocyte deformability injury during hypobaric hypoxia in rats].

Rats were randomized into sea level group and hyoxic group. Erythrocyte filtration index (IF), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), erythrocyte [pH]i, [Mg2-]i, [Ca2+]i and [K+]i/[Na+]i were investigated in our studies. The results were as follows: 1. IF was increared in hypoxic group (0.234 +/- 0.060) 2. [Ca2+]i of hypoxic group (7.02 +/- 1.66) was evidently increased and correlated with its IF (r = 0.7386, P < 0.01), but [Mg2+]i had no obvious changes, [K+]i/ [Na+]i ratio of hypoxic group was reduced and negatively correlated with IF (r = -0.3957, P < 0.05), meanwhile, [pH] of hypoxic group increased evidently. 3. There was no statistic difference between MCHC of hypoxic and sea level group, but MCV of hypoxic group increased. These findings suggest that the changes of [Ca2+]i, [K+]i/[Na+]i ratio, [pH]i and MCV may play important role in erythrocyte deformability injury during hypoxia.

Animals↗
PubMed1997

Effect of jiawei shenqi dihuang tang on the content of urinary protein in patients with diabetic nephropathy.

42 cases of diabetic nephropathy (DN) diagnosed as the type of kidney deficiency and blood stasis were treated with Jiawei Shenqi Dihuang Tang. The therapeutic effect demonstrated that various kinds of symptoms and sings were significantly improved. There was significant difference in the qualitative and quantitative examinations of urinary protein between pre- and post-treatment (P < 0.05).

Adult↗
PubMed1997

[Cardiovascular effects of diabetic autonomic neuropathy in NIDDM with coronary heart disease].

42 coronary heart disease (CHD) (21 with NIDDM) were studied with a noninvasive cardiovascular autonomic function tests Namely; 1. Heart rate response to valsalva manoeuvre; 2. Immediate HR response to standing; 3. BP response to standing; 4. BP response to sustained handgrip, on two groups; Group 1: 21 NIDDM with CHD; Group 2: 21 CHD. The results showed that the incidences of abnormal of 4 tests were: 28.6%, 42.9%, 19.0%, and 42.9% in Group 1 respectively, and all were 0% in Group 2. Significant difference (P < 0.05) was found between two groups. It suggested that cardiovascular autonomic function tests is useful in diagnosing autonomic neuropathy in NIDDM with CHD patients.

Aged↗
PubMed1997

[Experimental and clinical study on gastroesophagostomy after cardiectomy of gastric stump].

60 hybrid dogs, divided into 2 groups, were subjected to subtotal gastrectomy in B-I and B-II pattern respectively. 20 weeks later, resection of cardia and fundus ventriculi and the gastric remnant esophagus anastomosis was performed. There were more omentum blood vessel embedments about the gastrojejunostomic and gastroduodenostomic stoma and collateral circulation was plentiful. In 1980, there were 25 patients with cardiac cancer of the gastric stump with an average period of 13 years and 3 months following subtotal gastrectomy and a mean age of 59.1 years. 19 patients were subjected to exploratory thoractomy, 17 resection of cardia and fundus of gastric stump and gastroesophagostomy (9 to tunnel gastroesophagostomy and 8 end-to-side esophagogastrostomy). The largest tumor was 5 cm x 4 cm. Except for a death due to intestinal obstruction following operation, the others attained a good recovery. Resection of cardia and fundus of gastric stump and gastroesophagostomy can be carried out for patients with cardiac cancer for gastric stump, which is in line with the principle of conservation surgery.

Adenocarcinoma↗
PubMed1997

[Severe vascular injuries following total hip replacement].

Severe vascular injury following total hip replacement (THR) is very rare. It has an a incidence of 0.25% and poses a serious threat to the involved limb and the patient's life. Vascular structures affected include the external iliac artery and vein, femoral artery and vein. In 721 cases of THR 3 had vascular injuries. The first case sustained the injury of the external iliac vessel which was cut by the sharp edge of bone cement while removing the displaced prosthesis. The second had laceration of the iliac vein while a pneumatic drill was used in the anterion superior acetabulum, and the third had the cut injury of the femoral artery during resection of the capsular scar tissue. The understanding of the mechanisms and location of vascular injury during THR will help surgeons in early diagnosis and treatment of the injury.

Adult↗
PubMed1997

[A positioning device for oral paralleling technique].

OBJECTIVE: To design a reliable method for standardized paralelling dental projection, for comparison of the tiny variations of alveolar bone during the treatment of the periodontal disease. METHODS AND MATERIAL: Periapical radiographs in 29 pairs of films with this device and 14 pairs of films with traditional method on dried skulls were comparatively analysed by digital subtraction. Standard deviations and angle variations of subtracted image were studied comparatively between this method and traditional paralleling technique. RESULTS: Significant difference of reproducibility between two groups was showed. The reproducibility of the successive pictures was apparently increased when projected with positioning device.

Alveolar Process↗
PubMed1997

[PCR detection of Chlamydia pnumoniae DNA in nasopharyngolaryngeal swab samples from patients with rhinitis and pharyngolaryngitis].

A PCR assay was used to detect Chlamydia pneumoniae specific Pst I 474 fragment DNA in swabs from patients with acute or subacute pharyngolaryngitis or rhinitis and nasosinusitis. C. pneumoniae specific antibodies in sera were also assayed with microimmuno-fluoresence (MIF). About 28% of the patients (49/175) were PCR positive and 25.7% (45/175) were MIF antibodies positive. The accordance rate of the two methods was 91.8%. It is suggested that the C. pneumoniae Pst I 474 specific PCR is sensitive and specific for detecting C. pneumoniae in pharyngolaryngitis or rhinitis and nasosinusitis.

Chlamydia Infections↗
PubMed1997

[Ten-case report on primary cervical lymphoma].

OBJECTIVE AND METHODS: Clinical feature, treatment and prognosis of primary cervical lymphoma: are retrospectively analysied. RESULTS: The disease is rare, comprising about 0.9% of all primary cervical malignancies. The average age was 43.6 years. Seven cases had history of familial carcinoma. The complaints: abnormal vaginal bleeding and/or vaginal discharge. The usual pattern of growth was endophytic or polypoid. By FIGO cervical cancer, staging system, there were 8/10 stage I b, 1/10 stage II b and 1/10 stage IV. Histologically all were NHL, B cell lesions(7/10) were the diffuse, cleaved or cleaved-noncleaved cell type. Combination of surgery and chemotherapy were used for 9 of these 10 patients. The follow-up period was 3-66 months. Only one patient had relapse 41 months after the treatment while, others (9/10) survived with no evidence of the disease. CONCLUSION: The prognosis is favorable if cervical lymphoma is discovered early and treated properly.

Adult↗
PubMed1997

[A study on the action of tang niao kang decoction].

Experiments have verified that Tang Niao Karg (a preparation from Chinese medicinal herbs) taken orally does not decrease the blood sugar of empty stomach in mice, but markedly helps lower high levels of blood sugar and lipid induced by epinephrine and glucose in mice. For rat models of diabetes induced by 4-o-pyrincidine Tang Niao Kang can significantly lower the content of blood sugar, raise the insulin level of blood serum, and enhance the tolerance to sugar.

Animals↗
PubMed1997

[Pharmacological study on the compatibility of cortex Cinnamomi with Halloysitum Rubrum].

The decoction of Cortex Cinnamomi (CC, 1 g/kg p.o.) and Halloysitum Rubrum (HR, 3 g/kg p.o.) or the combination of the two drugs (4 g/kg p.o., CC 1 g/kg, HR 3 g/kg) could antagonize the diarrhea caused by p.o. water ex tract of Radix et Rhizoma Rhei in mice; and inhibit the platelet aggregation induced by ADP in vitro. Meanwhile, the effect of the combination of the two drugs was not different from that of each single one. In addition, CC was able to inhibit the spontaneous movement of intestine in situ and showed an analgesic effect (hot-plate method) in mice; HR was ineffective in these aspects and did not reduce the effect of CC. CC(20 g/kg p.o., i.p. or i.v.) exhibited very strong toxicity in mice, while HR(60 g/kg p.o., i.p. or i.v.) was nontoxic. When the two drugs were used together, the toxicity was markedly reduced.

Aluminum Silicates↗
PubMed1997

[Analysis of registration parameter of the dental radiographs for digital subtraction].

OBJECTIVE: To investigate the registration parameters in the dental radiographs for digital subtraction, to find out the significance of them and try to improve the quality control of the registration of the dental radiograph for the digital subtraction. METHOD: Sixteen projections of molar and premolar of mandible of minipigs were investigated for stability of the registration system of the dental radiographs. The rotation and the movements of the bite plans were measured with different height of edge of the bite plan. The 128 radiographs with varying parameters of the projection were digital subtracted. The noise of the subtraction photograph was compared for analyses of the relationship between subtraction noise and the projection parameters. RESULTS: The depth of the bite plan and the strength of the connect bar between the X-ray tube and the bite plans are the most significant parameters for the stability of the registration system. The thicker bar the better of the registration was. When the strength of the connected bar is increased, the depth of the bite plan is permitted not too strict. There is not significant effect for digital subtraction with other parameters in this investigation. CONCLUSION: For the best stability of the registration of dental radiographs, the connected bar with 8 mm in diameter is strong enough and the depth of the bite plan between 2.5-4 mm are adequate.

Animals↗
PubMed1997

[A longitudinal study of alveolar bone repair following non-surgical treatment in periodontitis].

The purpose of this study was to monitor post-treatment alveolar bone repair using digital subtraction radiography (DSR). 104 interproximal bone crestal sites were selected from 52 premolars in 9 periodontitis patients (6 male, 3 female, aged 29-63 years). Acrylic stents were used to ensure serial radiographs which were taken at initial visit, 2 weeks, and 1, 2, 3, 6, 9, 12 month(s) after scaling and root planning. Results showed: in some of the observed sites, small amount of bone increase was detected as early as two weeks after the non-surgical therapy. Statistically significant bone gain (P < 0.001) occurred at second month and peaked at 12 months after instrumentation. The increment of bone gain displayed an exponential curve. Three different patterns of alveolar bone reaction to treatment appeared among different patients. This study demonstrates that DSR is a sensitive and quantitative method in the monitor of bone fill after periodontal treatment.

Adult↗
PubMed1997

[Minor Bupleurum decoction in the treatment of viral myocarditis models].

A myocarditis model of Balb/c mice established by means of coxsackie virus type B3 was treated with the Minor Bupleurum Decoction. The results indicate that the decoction can regulate T lymphocyte subsets, influence anti-cardiac antibody production, help the organism to get clear of viruses, and thus plays an important role in treating viral myocarditis.

Animals↗
PubMed1997

[Preparation of liposomes of superoxide dismutase].

The liposomes of SOD were prepared by reverse-phase evaporation. By examining the important effects on preparation we obtained the liposomes of SOD. The encapsulation of SOD was more than 60%, and the stability of the liposomes was excellent.

Delayed-Action Preparations↗