Biomedical subjects

Z Zhou

Publications and source records attributed to Z Zhou.

At least 109 records · Page 6Linked to original sources

PubMed2001

[Experimental studies on muscle fatigue of human limb motion with FNS].

The basic characteristic of the functional neuromuscular stimulation signals suitable to body is preliminarily determined after the fatigue performance of the biceps, and the physiological reaction to stimulation is investigated using many continuous stimulation signal patterns. The flexion motion of the elbow joint (right hand) of a healthy man was taken as our research objective. The surface electrodes were connected to the biceps and a micro angle sensor was mounted on the elbow joint (right hand). The curves of angular displacement for the elbow joint motion were obtained by using functional neuromuscular stimulation (FNS) limbs motion measurement instruments. The results demonstrate that the biceps are characterized by the non-linear and time-variant no matter what the stimulation patterns are, that continuous slow stimulation signals can reduce the muscle fatigue of the biceps, and that the stimulation frequencies ranging from 30 Hz to 50 Hz are applicable to the neuromuscular system.

Adult↗

PubMed2001

[Construction and expression in eukaryotic cells of HBsAg and B].

OBJECTIVE: To investigate the enhanced role of B(7-1) in gene immunization of eukaryotic vector expressing HBsAg, and further to eliminate the immunotolerance to hepatitis B virus. METHODS: B(7-1) and IRES-HBs with linker and promoter sequence prior to HBs gene were amplified with high fidelity PCR, then subcloned into plasmid pBluescriptks+, which was used to sequence. The eukaryotic expressing vector was constructed by inserting B(7-1) and IRES-HBs into plxsn. Recombinant vector was transfected into PA317 by means of lipid mixtures. Titre of pseudovirus packaged in PA317 cells was detected by infecting NIH3T3 cells. B(7-1) and HBsAg expression in PA317, NIH3T3, HepG(2), 293, EL4 cell lines was detected by RT-PCR, immunohistochemistry and ELISA, respectively. RESULTS: No change was found in the sequences of target genes amplified by high fidelity PCR compared with the known sequences. Plxsn-B(7-1)-HBs was constructed by first inserting B(7-1) into plxsn with enzyme EcoRI/XhoI, then IRES-HBs was inserted in the same way with enzyme XhoI/BamHI. 43 and 90 G418-resistant clones were obtained two weeks later after 1:10 and 1:5 passages at 24 hours after transfection. Titre of the peudovirus was 5.4x10(5) CFU/ml. B(7-1) was expressed in all the cell lines above by RT-PCR test. The contents of HBsAg in the supernatant of the PA317, NIH3T3, HepG(2), and 293 cells at 24, 48, 72 hours intervals were 0.15, 0.11, 0.20, 0.13; 0.63, 0.47, 0.76, 0.58; 0.77, 0.61, 0.89, 0.69, respectively. CONCLUSIONS: The retroviral vector expressing B(7-1) and HBsAg simultaneously is constructed successfully. The target antigens are expressed in above cell lines in vitro after transfection with lipids mixtures. It may be used to conduct gene immunization and to investigate the role of B(7-1) on HBsAg immune response, which may be further used to the prevention and therapy of hepatitis B.

Animals↗

PubMed2001

[The experimental study of Sr-HAP on reconstructing mandibular bone defect].

OBJECTIVE: Different ration of Sr-HAP was implanted in animals to study the bioreactions in order to prepare for the clinical applications in future. METHODS: 24 rabbits were divided into 3 groups for study. Bone defect of 6 mm x 12 mm x 4 mm was made at the mandibular angle of rabbits and Sr-HAP of different proportion (10%, 5%, 0%) was applied to reform the defect. One group of animals were killed at 1 month, 3 months, 6 months to evaluate the biologic capacity with anatomy, histology, SEM, tetracycline fluorescent marker, ECT and ration histology. RESULTS: Sr-HAP had hardly been rejected by hosts, and in early period after operation the new bone in the Sr-HAP was found with great quantities as the degradation of Sr-HAP much more than that in the pure HA, and the difference of bone quantity can be shown in statistics. CONCLUSIONS: 1. Sr-HAP has a better biocompatibility, biodegradation than pure HA and a excellent osteoinductivity. The existence of Sr-HAP improves the total new bone quantity and the interface of bone, also prolongs the period of new bone increasing. 2. Sr-HAP has a good biodegradation and suitable speed of biodegradating, so the reconstruction effect with Sr-HAP is fairly satisfactory.

Animals↗

PubMed2001

[Influence of surface roughness of pure titanium on accumulation of bacterium].

OBJECTIVE: The aim of this investigation was to evaluate the influence of surface roughness of pure titanium on adhesion of bacterium. METHODS: A total of six edentulous volunteers with healthy oral mucosa participated in an in vivo study. Four kinds of pure Titanium testing pieces with different surfaces were fixed in the polished surface of upper complete dentures and the other in the tissue surface of the dentures. After 6-month wearing the dentures, the amount and species of bacterium adhered on pure Titanium were examined. RESULTS: (1) Individual difference had a significant influence on amount of bacterium adhered on pure Titanium, but had no relation to species of bacterium according to Gram's staining. (2) To the same patient, with the increase of roughness, bacterium adhered on samples improved in amount (P < 0.01), but remained the same in composition. Wrinkly samples collected more bacterium than plane samples and exhibited G- coccus beside G+ coccus. Comparing two samples with same roughness, the one with roughness on the tissue surface of the denture collected less bacterium than that on the polished surface (P < 0.01), and predominantly presented G- rod bacterium and coccus, which was completely different to that on the polished surface. CONCLUSION: From the perspective of benefit to periodontal tissue, plane surface should be adopted when framework of pure Titanium is made, and polishing of the prosthesis after being modified should be paid more attention, especially on the tissue surface.

Bacteria↗

PubMed2001

[Landscape structure and greenland spatial pattern in workshop district of Wuhan Iron and Steel Company].

The landscape structure and greenland spatial pattern in the workshop district of Wuhan Iron and Steel Company were investigated and analyzed on the basis of landscape ecological theory. The results showed that the main parts of the landscape structure were the artificial landscape elements such as building and concrete covering patches, highway and railway bed corridors, and industrial reservations. All of these artificial landscape elements accounted for 74.37% of patch area and 57.70% of patch dominance. In the landscape, the building and concrete covering land had the maximum percentage of patch area (56.43%) and the maximum dominance (35.59%). The special purpose greenlands had the highest fragmentation index (5.0591 ind.hm-2) and the wide-ranging distribution. The corridor density (13.78 km.km-2) was high, and the highway had more effects on landscape than the railway. All the results reflected not only the essential landscape features of industrial region, but also the rational trend of landscape structure in the workshop district of Wuhan Iron and Steel Company. In the greenland, the road greenbelts had the maximum patch number, area percentage (66.07%), and dominance (75.31%), the shelter forests being mainly composed of tree species had high patch average area (8454.45 m2) and environmental benefit, and the ornamental greenlands had abundant plant species and varied scenery. The greenland system was initially formed by four afforestation districts, using shelter forests and ornamental greenlands in large patch as a center connected by road greenbelts. It should be attached importance to the relatively high dominance of wild grasslands, the low area percentage of shelter forests and the imperfect road greenbelts to develop the uncovered lands and to improve the quality of the greenland system.

China↗

PubMed2001

[Study on the mechanism of thrombosis by lupus anticoagulant inhibited protein C pathway].

OBJECTIVE: To study the mechanism of thrombosis in systemic lupus erythematosus (SLE) patients with protein C (PC) pathway inhibition by lupus anticoagulant(LA). METHODS: Phosphoethylamine(PE) dependent activated protein C (APC) inhibiting assay (modifed DRVVT) was used to observe the inhibition of APC activity after incubation of IgG from both normal and SLE patients with PE. RESULTS: The activity of anticoagulation of APC was augmented by PE. Proportionally to its concentration, LA could inhibit the PE dependent anticoagulation of APC. The inhibition of LA-IgG on APC in the LA positive SLE patients with thrombosis was stronger than that in LA negative non-thrombosis patients; but IgG has no effect on the APC activity in normal person. CONCLUSION: LA inhibiting the PC pathway by interfering with PE may be the important reason of thrombosis in SLE patients.

Dose-Response Relationship, Drug↗

PubMed2001

In-vitro cultivation of normal human oral keratinocytes.

OBJECTIVE: To establish a method for culturing normal human oral keratinocytes. METHODS: Specimens obtained from healthy humans undergoing oral surgery were dissociated into single cell suspensions by dispase and trypsin. The cells were grown in serum-free medium. Morphological characteristics were studied under light microscope and electron microscope. Cytokeratins were shown by immunohistochemistry. RESULTS: Cells could be maintained in culture up to 4-5 passages or 30-50 days. Electron microscope revealed that there were desmosomes and tonofibrils in the oral keratinocytes. The cells showed positive staining for cytokeratin antibody. CONCLUSION: Human oral keratinocytes have been successfully grown in serial culture.

Cell Culture Techniques↗

PubMed2001

[Expression level of c-erbB-2 protein correlates with the prognosis of patients with colorectal cancer].

OBJECTIVE: To study the expression level of c-erbB-2 gene in colorectal cancer and its correlation to prognosis. METHODS: In 173 colorectal carcinoma patients, c-erbB-2 protein was examined immunohistochemically and patients' prognosis was evaluated by retrospective analysis combined with follow-up data. RESULTS: The immunohistochemical staining of c-erbB-2 protein was found in the cytoplasm and membrane with a positive rate of 52% in tumor tissue. The 1-, 3-, 5- and 10-year survival rate of patients with negative c-erbB-2 expression was 98.7%, 92.4%, 87.1% and 84.1% respectively; that of the patients with weakly positive c-erbB-2 expression was 94.5%, 76.1%, 72.3% and 68.3%, respectively. In contrast, that of patients with strongly positive c-erbB-2 expression was 91.0%, 43.5%, 36.8% and 23.4%, respectively. The survival rates among the three groups of patients were statistically different. Multivariate survival analysis by Cox regression model showed that c-erbB-2 expression level was a risky prognostic factor for colorectal cancer. CONCLUSION: The expression level of c-erbB-2 protein is an independent prognostic factor in colorectal carcinoma.

Adult↗

PubMed2001

[A comparative study of friction behaviour matching of natural tooth and new type dental prosthetic materials--titanium].

New type dental prosthetic materials Titanium not only have excellent biocompatibility, better corrosion resistance, appropriate hardness, light density approaching to human skeleton, but also good mechanical properties as those of type II, IV gold alloy recommended by ADAS, and their strength to weight ratio is 1.3 times that of aluminum, 1.5 times that of steel. Friction wear comparative tests of natural living teeth and dental Titanium materials have been carried out against Gr15 steel ball. A reciprocating movement was realized at the modified machine of fretting to simulate the pair of real tooth. The main test parameters were: slip amplitude 500 microns, normal load 20 N, frequency 2 Hz, and number of cycles 5000. The wear behavior results show that titanium is comparatively a prospective dental materials for restoration.

Child↗

PubMed2001

[Study of resisting leukoplakia canceration and angiopoiesis by herba erigerontis].

OBJECTIVE: To evaluate the effect of resisting canceration of herba erigerontis and that of angiopoiesis. METHODS: Carcinomatous conversions of golden hamster cheek pouches induced by Salley way and obstructed by herba erigerontis were studied. Ink perfusion, analysis of images, resin cast form of micro-vessel, alpha-SMA detection and histopathological examination were applied to observe their changing patterns. RESULTS: The rate of leukoplakia canceration of herba erigerontis group was one time lower than that of model group. The rate of normal cells was about four times more than that of model. alpha-SMA of herba erigerontis was higher than that of model (P < 0.001). There was no significant difference between angeion vessel area and density (P > 0.05). Nevertheless, the resin cast form of micro-vessel showed that its configuration and spacious arrangement was similar to control group. CONCLUSIONS: Herba erigerontis has the function of preventing leukoplakia canceration. It has no obvious effect on angio-hyperplasia and expansion in the course of leukoplakia canceration. However, it has the protecting function on angio-configuration and spacious arrangement and the complete of angeion vessel wall. Probably its mechanism is to promote blood circulation by removing blood stasis and benign angiopoiesis so as to resist canceration.

Actins↗

PubMed2001

Changes of blood circulation of the extremity after external fixation for tibia shaft defect: an experimental study.

OBJECTIVE: To assess and compare two approaches, end to end compression with lengthening (EECL) and segmental bone transport by lengthening (STBL), for long tubular bone defect and nonunion. METHODS: Ten goats were used to establish the bone defect model of the mid-tibia. The bone defect ends were shortened step by step with a sulcated half-ring external fixator. Changes of the blood flow of the distal extremity were measured with pulse-Doppler monitor and angiography. RESULTS: The blood flow in the distal extremity was not affected when bone defect was less than 15% of the original length. Blood circulatory disorder would appear in the distal extremity when bone defect ranged 15%-20% of the original length. The necrosis would appear in the extremity because of the blood circulatory obstacle when bone defect was more than 20% of the original length. CONCLUSIONS: EECL is an appropriate alternative of treatments if bone defect is less than 15%; while SBTL may be feasible if bone defect is over 20% of the original length. When bone defect ranges between 15% and 20%, EECL should be applied with great care on condition of keeping watch on the extremity circulation with pulse-Doppler monitor.

Angiography↗

PubMed2001

[Effects of pyracantha fortuneana extract on blood coagulation].

OBJECTIVE: To study the effect of the Pyracantha fortuneana extract and its defferent polar fractions on blood coagulation. METHODS AND RESULTS: The Pyracantha fortuneana extract could noticeably shorten the coagulation time of glass slide in mice (P < 0.05) after oral administration, and also shorten the recalcification time and prothrombin time in vitro (P < 0.01, P < 0.05), while in three polar fractions of the extract, the effects of the chloroform phase that could shorten the coagulation time of glass slide in mice(P < 0.01) after oral administration, and also shorten the recalcification time and prothrombin time in vitro (P < 0.01) are more noticeable than that of the acetic ether phase (P < 0.01, P < 0.05). The petroleum ether phase has no above-mentioned effect (P > 0.05). CONCLUSION: The Pyracantha fortuneana extract can reduce the blood coagulation. Both the chloroform phase and the acetic ether phase of the extract have activity of blood coagulation, but the petroleum ether phase does not.

Animals↗

PubMed2001

[The blood drainage of Langerhans islets with special reference to the functional and clinical significance of pancreatic exocrine part].

OBJECTIVE: This study sought to gain an insight into the blood drainage of Langerhans islets with special reference to the functional and clinical significance of pancreatic exocrine part. METHODS: Observations were carried out in 11 human dead bodies, 40 monkeys, 24 dogs, 62 rats and 24 rabbits by scanning electron microscopy and light microscopy with the technique of retaining microcirculatory dynamic and tissular information in the static specimens, microvascular serial reconstruction, and/or by intravital fluorecence microscopy with FITC-labeled erythrocytes. RESULTS: Three patterns of islet drainage channels drained into different acinar regions with different features and insulo-insular drainage channels observed in the primates were found in this study. The authors suggest that these patterns might be termed as follows: 1. Continuous drainage vessels. All islets possessed these capillary-sized portal vessels which ran a short distance, and then drained into the peri-islet acinar region. 2. Convergent drainage vessels. Some islets possessed one or two, occasionally more, of these portal vessels, which were relatively long and/or thick and drained into the acinar region far away from the islet in the lobule. 3. Translobular drainage vessels. These portal vessels crossed the interlobular septum into an adjacent lobule where sometimes no islet existed, and then drained into the exocrine acinar region 4. Insulo-insular drainage vessels. Some islets in the monkey and human, possessed these vessels which drained into an adjacent small islet through the insulo-insular drainage vessels. CONCLUSION: Langerhans islets possessed the consummate drainage system which drained into different exocrine acinar regions, suggesting that the release of islet hormones is in some way necessary for the exocrine secreting function, and that the reduction of local insular hormone levels in insuloacinar portal circulation and the impairment of insular drainage vessels would be the morphological basis of the pancreatic exocrine pathologic lesion in human diabetes.

Adult↗

PubMed2001

[Protective effect of berberine on isolated perfused heart in heart failure].

OBJECTIVE: To examine the protective action of berberine against the development of heart failure. METHODS: Wister rats were divided into two groups. The Langendorff perfusion of isolated heart was performed and Verapamil was used to bring about acute heart failure. The experiment group was given berberine (10(-6) mol/L) before the use of Verapamil, but the control group was not given the berberine. A comparison was made on the degree of heart failure between the two group. RESULTS: The degree of heart failure in the experiment group was significantly less severe than that in the control group (P < 0.001). CONCLUSION: Berberine has the protective action against to the development of heart failure.

Animals↗

PubMed2001

[Application of corepraxia in the implantation of intraocular lens].

PURPOSE: In the cases of aphakia or cataract which complicated with iridosteresis, corectasis and pupil displacement, corepraxia was performed when implanting intraocular lens (IOL) in order to recover the normal shape and position of pupil, improve postoperative visual acuity and prevent monodiplopia and glare. METHODS: In the cases which have iridosteresis at the direction of 9-3 oclock or updrawn pupil, iris suture was performed at the incision directly(open method); while those at the direction of 3-9 o'clock, operation was performed outside the anterior chamber (close method). RESULTS: In 22 cases, the percentage which having visual acuity better than 0.5 is 65%, having nearly round shape pupil 67%, having pupil diameter less than 3 mm 73%, having normal pupil position 67%. CONCLUSION: All kinds of deformed pupil can be recovered to their normal shape, size and position by performing corepraxia while IOL was implanted. The prolene has light reaction and better effect in iris suture.

Adolescent↗

PubMed2001

[Impact of WPY on pancreatic microcirculation of acute pancreatitis in mice].

OBJECTIVE: To explore the pathogenesis of acute pancreatitis (AP) and evaluate the effect of a Chinese herb WPY on the course of AP. METHODS: Intravital fluorescence microscopy was used. The pancreatic microvascular diameter, RBC velocities and functional capillary density (FCD) were estimated following intracutaneous injection of caerulein alone or with gastropipe WPY. RESULTS: Caerulein mediated a significant decrease in functional capillary density (FCD), RBC velocities and diameter of interlobular arteriole (P < 0.01). Compared with AP group, WPY was effective in restoring functional capillary density, interlobular arteriole diameter and RBC velocity. CONCLUSION: Impairment of pancreatic microcirculation in the early phase of acute pancreatitis may play a key role in the progression of this disease. Possible contributory mechanisms include reduced blood flow and functional capillary density, interlobular arteriole spasm, and leukocyte-endothelial cell interaction. WPY has a beneficial effect on the course of acute pancreatitis. Possible causes include attenuating microcirculatory failure.

Acute Disease↗

PubMed2001

Relation between alkaline phosphatase in gingigval crevicular fluid of implant teeth and the curing result.

OBJECTIVE: To discover the relation between alkaline phosphatase (ALP) in gingival crevicular fluid (GCF) of implant teeth and the curing results. METHODS: We measured the ALP level in GCF among 56 cases of implant teeth which included 2 failed cases, 5 cases with bad oral hygiene and gingivitis, and compared it with that in the normal group composed of 10 persons. RESULTS: The ALP levels in normal group and success implant group showed no difference. The ALP levels in normal group and success with gingivitis group showed obvious difference. The ALP levels of the 2 failed cases are the highest of all. CONCLUSIONS: The ALP level in GCF is an important index in evaluating the curing result of the implant teeth.

Adult↗

PubMed2001

[Relation between alkaline phosphatase in gingival crevicular fluid of implant and the curing result].

OBJECTIVE: To investigate the relation between alkaline phosphatase (ALP) in gingival crevicular fluid (GCF) and prognosis. METHODS: We measured the alkaline phosphatase in gingival crevicular fluid among 56 cases of implant tooth which included 2 failed cases, 5 cases in bad oral hygiene and with gingivitis, compared with the normal group consisted of 10 healthy persons. RESULTS: The difference of ALP level between normal group and success implant group is not significant, but between normal group and success with gingivitis group is significant(P < 0.05). The ALP level of 2 failed cases are highest (because of few failed cases, no statistics was done). CONCLUSIONS: The ALP level in GCF is supposed to be an important index in evaluating the result of the implant.

Adult↗