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Volume ， Issue 4 ， 1989
- Abstract：<正> Free radicals in ischemic and reperfused rat brain were measured by electron spinresonance（ESR） spectrometer.The inhibitory effect of allopurinol on the free radical genera-tion in reperfused rat brain was observed.The experimental results revealed that the free radi-cal content of the brain in the ischemia group was markedly higher than that in the control group（P<0.01）,that in the reperfusion group was markedly higher than that in the ischemia group（P<0.01）and that in the allopurinol group was markedly lower than that in the reperfusiongroup（P<0.01）.These results suggest that free radicals increase.greatly after cerebralischemia-reperfusion and that allopurinol plays a certain inhibitory role in the free radical genera-tion in the reperfused rat brain.0|6|0Updated：2026-03-12
- Abstract：<正> Various chemical and gas-liquid chromatographic analyses indicate that the lipid A,backbone of the lipopolysaccharide（LPS）isolated from B.fragilis NCTC 9343 is chemically con-stitutεd by a β1,6-interlinked D-glucosamine disaccharide.It is phosphorylated at its 1-positionby a glvcosidic-linkage while the ester-linked phosphate at 4’—position present generally in otherlipid A is depleted.The lipid A is lower fatty acylated in the amount of 5.2 fatty acids/lipid Amolecule（of which 0.73 forms 3-acyloxyacyl groups）.The LPS containing such an incompletelipid A component has been shown endowina with a weaker endotoxicitv.0|10|0Updated：2026-03-12
- Abstract：<正> At different,time after copper wire induced into the vitreous of the rabbits,malondialdehydes（MDA）in the retinas and trace element coppar in the aqueous humor and Pa-thology were observed.One day after the induction of copper,the level of MDA increasedabout three times in the retinas of experimental eyes as compared with the control eyes（p<0.01）and the amplitude of electroretinography（ERG）dropped rapidily following increase ofcopper ions in the vitreous.The tncrease of concentration of copper ions in the vitreous wasclosely correlated with that of MDA in the retinas （p<0.01）.Early EM examination of ex-perimental eyes reveaisd damage of retinal membranous structure rich in oxygen andpolyunsaturated acid（PUFA）,including the ovaer and inner segments of the photoreceptors.These results indicate thu copper-induced isptd peroxidation is an important cause of retinaldumage.0|2|0Updated：2026-03-12
- Abstract：<正> An arumal model to study smoke inhalation injuries was established in the sheep.22adult mate sheep were forced to inhale saw-dust smoke of pine wood for 6 minutes through anendotracheal tube.Pulmonury compliance,arterial blood gases,carboxyhemoglobin,andoxyhemoglobin were monitored and the morpholgical chanhes of the tracheobronchial tree andpulmonary parenchyma were studied with optical and eletron microscopy.Severe carbon monoxide poisorung with fatal blooa level of carboxyhemoglobin（higher than50％） was found at the end of smoie inhalation.Acute respiratory distress,progressivehypoxerrua decreased pulmonary compliance and increased P（A-α）O2 and Qs/QT oecurred af-ter the injury.Tracheobronchial blockage due to pseudomembranous cast,pulmonary edema,atelectasis,and necrosis of pulmonary epithelium were demonstrated on histological sections.The mechaniisms of carbon monoxide poisoning ane acute respiratory failure was discussed.0|3|0Updated：2026-03-12
- Abstract：<正> It is reported in this article that the mandibular unilateral distal-extension remova-ble partial dentures with wrvught wtre retentive clasp arm,cast circumferential retentive arm andI-bar retentive arm were tested under vertical loading,and the stresses around the root of thetooth adjacent to the extension base were ovserved by means of photoeiastic stress analysis.The results showed that the retentive clasp arm or reciprocal clasp arm in distal-extension remov-able partial denture does not affect the magnitude and direction of the abutment tooth force,that there is no obvious difference among the wrought wire clasp arm,cast circumferential clasparm and I-bar clasp on the abutment tooth force,and that the force created due to loading of re-movable partial denture is transmitted to the primary abutment tooth mainly through theocclusal rest.0|3|0Updated：2026-03-12
- Abstract：<正> The appearance of HBV DNA in the liver and serum of 15 patients with hepatitisB conifected with HDV was observed and compared with that of 13 HDV-negative cases.Itwas found that HBsAg titer was lower than or equal to 1:4 in 8 HDV-positive patients,inwhom it was temporally negative in 5,and negative during the,two-day hospitalization in 1.No similar result could be observed in the HDV-negative cases.The detection rate of HBVDNA in both the HDV positive and negative groups was 20.0％ （3/15） and 25％ （3.12） in se-rum,and 46.7％ （7/15） and 61.5％ （8/13） in the liver rcspectively.There was no signif-icant statistical difference between the 2 groups.The HBV DNA grains detected with in situ hybridization,with biotinylated HBV DNAprobe were demonstrated in the sparse type of distribution in 3 cases and lightly stained in 2.Itis believed that HBV DNA replication activity might be suppressed by HDV.However activeHRV DNA replication was also present in some HDV-positive patients and HBV DNA was posi-tive in both the liver and serum in 3 such patients.It was concluded that the difference of the detection rate of HBV DNA in HDV-positivepatients might be related to the different stages of HDV infection.0|4|0Updated：2026-03-12
- Abstract：<正> Met-and Leu-eukephalin injected into lateral ventricles could decrease serumcorticosterone level in healthy rabbits.This effect could be reversed by giving naloxone.Fif-ty min after burn（third degree,30％） serum corticosterone of rabbits increased verysignificantly over controls,and pretreatment with dexamethazone had no negative feebdack ef-fect.Enkephalin failed to lower serum corticosterone from its increased level following burn.These results suggest that enkphalin act poasibly as a neurotransmitter or neuromodulatorwhich takes part in the modulation of corticosterone secretion.0|4|0Updated：2026-03-12
- Abstract：<正> The types of DNA content ean be divided into four groups:（1）diploids andnera-diploids;（2）triploids;（3）tetraploidy and hyperploidy aneuploids;（4）biclonal DHAcontent.Recent studies show that measuring DNA content by flow cytometry（FCM） can beapplied to most primary bone lumors in pointing out clinicatly relevant informattons.Ii thisstudy,cellular DHA content of 33 primary bone tvenors was analysed by FCM Isolated ratcle-ar suspensions were prepared by a simple,rapid and effective method using 10％ formatin-fctedand paraffin-embeuded bone tumor specimens.The results showed that 10 benign（inchtding 5Grade I giant cell tumors of bone） and 5 histologically questionable tumors had nornufl DNAcontent （diploids or near-diploids）and the other 7 questionable and of the 11 malignanttumors had abnormul DNA content（aneuploids）.The cell cycle distribution analysis showedthat the aneuploidy tumors had higher proponion of S-phase and G2+M-phase cells than the nor-mal ploidy tumors,indicating there were differences in proliferative activity.The method alsoshowed that beniga and low-malignant primary bone tumors were diploids or near-diptoids,andhigh-malignant cnes were aneuploids Compared with typically pathological grading,the flowDNA analysis of bone tumors can more objectively point out their biological behavior andprognosis.0|3|1Updated：2026-03-12
- Abstract：<正>In order that the involved teeth might survive TA2&TC4 endodontic-endosseousimplanation was performed in 27 teeth（18 with periodonto-endodontic combined lesion andwith periodontitis）.Ajter 1-34 months’obseroation,6 teeth were prominently improoed,15improoed and 6 had no change.For the purpose of observing the ccnditon of implants inbones,endodontic-endosseous implantation was performed in ■ of a dog,with the implantsbeing TA2 for ■ and TC4 for■.Seventeen months later,the animal was killed.Analysisof SEM and electron microprobe findings showed that Ca was attached to both TA2 and TC4imlants.Histological sections showed connective tissue capsule formation with osteoid tissueat the bottom and lateral wall.0|7|0Updated：2026-03-12
- Abstract：<正> A gross morphological classification of 66 small hepatocellular carcinomas （SHCC,≤3 cm in diameter）and a determination of the DNA-content in 20 SHCC and 26 LHCC（larger hepatocellular carcinoma,>3 cm in diameter）by image analysis technology were studiedin this paper.It was showed that SHCC could be divided into three types:Type I,non-capsule type （n=13,19.7％）;type II,capsule type（n=47,71.2％） and Type III,infiltrative type （n=6,9.1％）.The Type I and Type II SHCC mainly had diploid DNAstem line,while Type III SHCC mainly haa aneuploid DN A stem line.In patients with≤3cmSHCC,the postoperative 5-year survival rate was 75％,significantly higher than that of 42.3％in patients with>3 cm LHCC （P<0.05）.There was no positive correlation between the tu-mor size and serum AFP level in this series.The results suggest that SHCC of≤3 cm in sizebasicaily reflects the relatively berugn btotogical characteristics of early hepatocellular carcinomaand is the best opportunity to acmeve the best curative results.But a small part of SHCC ex-presses markediy increased malignant biological behaviours due to the acceleration of stem lineselection.Up to now,as to the atscovery of the SHCC,the quantitative measurement of serumAFP level is still an effective and generally accepted method.0|4|0Updated：2026-03-12
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The Effect of Ultrasonic Method for Preparing Root Canals:A Scanning Electron Microscopic Evaluation
Abstract：<正> Sixteen fresh extracted human teeth paired according to their anatomic locations,were divided into two groups at random.The root canais of the teeth in Group 1 were preparedwith an ultrasonic unit and those of Group 2 with hand instruments.Then,the specimens wereobserved under a scanning electron microscope and their pnotographs were taken.Blindevaluation of cleanness was performed for each canal.Statistical dnalysis of the data indicatesthat the canal walls were cleaner in Group 1 than in Group 2 and that the ultrasonic preparationtook less time.0|5|0Updated：2026-03-12 - Abstract：<正> Histochemical study and determination of cytochrome oxidase （CTO） relative activ-ity with a Leitz MPV-III microspectrophotometer in different regions of normal rat brain werecarried out.9 healthy male Wistar rats were divided randomly into 2 groups;an enzyme activi-ty studied group and a control group with HE staining.It was found that 2 kinds of CTO distri-bution areas exist in the brain of rats;the high activity area including cerebral cortex,corpusstriatum （gray matter）,thalamus,cerebellar cortex,etc,and low activity area including corpuscallosum,corpus striatum （white matter）,hippocampus,cerebellar white matter,etc.The dif-ference of CTO activity between the 2 areas is statistically significant （P<0.01）.Moreover,according to the intensity of positive response to CTO detecting stain,the granular layer of thecerebellum can be classified as cytochrome oxidase richly-contained area（CTORA）orcytochrome oxidase poorly-contained area （CTOPA）.The CTO activity of the former issignificantly higher than that of the latter（P<0.01）.0|3|0Updated：2026-03-12
- Abstract：<正> Solid Phase enzyme-linked Immunosorbent assay（ELISA） for detectingclass-specific rheumatoid factor （RF） was established.Aggregated rabbit lgG was used ascoating antigen and the presence of RF was demonstrated by F（ab’）2 fragment of anti-humanIg conjugated to horseradish peroxidase（HRP）.The results showed that high levels ofIgM-RF,IgG-RF and IgA-RF were found in patients with rheumatoid arthritis.A positive cor-relation existed between IgM-,IgG-,IgA-RF and disease activity.The presence of vasculitis al-so correlated positively with the levels of 3 class-specific RFs.0|7|0Updated：2026-03-12
- Abstract：<正> In the present study,AFP-specific immune RNA（iRNA） was shown to induceplaque-forming cells（PFC）from mouse splenocytes with a minimal effective dose of 31 μg/mland an optimal dose plateau ranging from 125 μg/ml to 250 μg/ml.This action of iRNA may beobserved on the first day of in vitro culture of mouse spleen cells.The iRNA preparation wasproved sensitive to RNase,but not to DNase and pronase.In addition immunofluorescencetest revealed that AFP-specific iRNA is capable of inducing the expression of membranousanti-AFP antibodies or AFP receptors in mouse spleen cells.0|1|0Updated：2026-03-12
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