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91.
92.
R. Pontoriero J. Lindhe S. Nyman T. Karring E. Rosenberg F. Sanavi 《Journal of clinical periodontology》1989,16(3):170-174
The present investigation was designed to evaluate the regenerative potential of the periodontal tissues in degree III furcation defects at mandibular molars using a treatment procedure based on the principle of guided tissue regeneration. The patient sample included 21 patients, 26-65 years of age, who presented periodontal lesions in the right and left molar regions including "through and through" furcation defects. After an initial examination, each patient was subjected to a series of full-mouth scaling and root planing. 2-3 months later, they were recalled for a baseline examination. The furcation-involved molars were randomly assigned in each patient to either a test or a control treatment procedure. The test procedure included the elevation of muco-periosteal flaps at the buccal and lingual aspects of the molars. Granulation tissue was removed and the exposed root surfaces were debrided and planed. The width and the height of the entrance openings to the furcation defects were assessed. A teflon membrane was adjusted to cover the entrances to the defects (buccal and lingual) and was retained in the manner described by Pontoriero et al. (1988). The flaps were repositioned on the outer surface of the membrane and secured by sutures which were removed after 10 days. Following surgery, the patients were instructed to rinse the mouth twice daily for 4 weeks with chlorhexidine gluconate. The membranes were removed after a healing period of 1-2 months. A surgical procedure identical to the test procedure was performed in the control tooth regions with the exception of the placement of membranes.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
93.
Functional aspects of serotonin transmission in the basal ganglia: a review and an in vivo approach using the push-pull cannula technique 总被引:4,自引:0,他引:4
Peripheral deafferentation of the rodent olfactory bulb results in loss of dopamine content, tyrosine hydroxylase activity and immunocytochemical staining for tyrosine hydroxylase in juxtaglomerular dopamine neurons. Reinnervation of the bulb by afferent neurons results in the return of all parameters to control levels suggesting that the dopamine neurons did not degenerate but that the expression of tyrosine hydroxylase enzyme was transneuronally regulated in a static population of juxtaglomerular cells. To evaluate this possibility, we determined the activity and immunocytochemical localization of the second enzyme in the dopamine biosynthetic pathway, DOPA decar?ylase. At a time when tyrosine hydroxylase activity was reduced to 25% of control values, DOPA decar?ylase activity in the lesioned bulb was maintained at about 65% of that in the unlesioned bulb. Immunocytochemical staining with antibodies to both enzymes, performed sequentially in the same sections, demonstrated that in the unlesioned bulb tyrosine hydroxylase and DOPA decar?ylase are co-localized in the same population of juxtaglomerular neurons. Similar results were obtained in adjacent sections each stained with one of the two antibodies. In contrast, in the deafferented bulb, about three times as many neurons were stained with DOPA decar?ylase as with tyrosine hydroxylase antibodies. The DOPA decar?ylase activity measurements and immunocytochemistry argue for the continued presence, in the lesioned olfactory bulb, of a population of tyrosine hydroxylase deficient dopamine neurons.The data suggest that olfactory receptor cell innervation transneuronally regulates the expression of tyrosine hydroxylase by mechanisms separate from those controlling the levels of DOPA decar?ylase. 相似文献
94.
I. V. Stupin A. I. Novokshonov A. M. Domborvskii G. G. Belous M. Yu. Ivanov 《Bulletin of experimental biology and medicine》1990,110(4):1407-1409
Department of Experimental Surgery, Interfaculty Laboratory Complex, and Department of Clinical Laboratory Diagnosis, Postgraduate Medical Faculty, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Kupriyanov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 110, No. 10, pp. 413–145, October, 1990. 相似文献
95.
本文采用液氮浅低温冷冻疗法治疗50例急性冠周炎患者,取得了良好临床效果,并于冷疗前后对血及唾液中IgG、IgA、IgM和血中C3及淋巴细胞转化率进行了免疫状态研究。实验结果表明,冷疗后系列免疫指标明显增高。故认为冷冻治疗冠周炎的主要机理是提高机体的免疫功能。 相似文献
96.
T. I. Shklyar 《Bulletin of experimental biology and medicine》1977,84(5):1631-1632
Wounds 1 cm long, down to the cutaneous muscle, were inflicted on rats aged 11 days, 2 months, and 2.5 months in the subscapular region. Nociceptive stimulation was applied to the animals by means of an electric current 48 h after the operation. Mitotic activity was determined in cells of the stratum basale of the skin epithelium adjacent to the wound. Nociceptive stimulation was found to reduce the mitotic index of the cutaneous epithelial cells of the animals of all age groups studied by a considerable degree (by several times). An increase in the mitotic index was observed from the early to the later stages of postnatal ontogeny.Laboratory of Age and Evolutionary Physiology, Voroshilovgrad Pedagogic Institute. Laboratory of Growth and Development, Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 11, pp. 605–606, November, 1977. 相似文献
97.
O. N. Tatarinova T. N. Lukyanova M. A. Zaitseva K. Yu. Veremeev V. A. Karpov A. N. Chuvilin D. D. Petrunin G. E. Pozmogova 《Bulletin of experimental biology and medicine》2008,145(3):312-316
Analysis of the use of real-time PCR with fluorescent registration of results for gene diagnosis of infectious diseases showed
that the sensitivity and reliability of quantitative evaluation of DNA targets directly depended on the method of purification
of oligonucleotide probes. Chromatographic behavior of synthetic probes carrying various fluorophores and fluorescence quenchers
was analyzed. Approaches to optimization of purification methods are proposed enabling elimination of previously undetectable
admixtures. The importance of these studies is explained by the need in extending the armory of methods for the development
and production of diagnosticums for detection of infectious and hereditary diseases, identification of genetically modified
organisms, and for a wide spectrum of research in molecular biology and medicine.
__________
Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 3, pp. 280–284, March, 2008 相似文献
98.
Yoko Kamitani Eiji Kajii Toshio Suda Shigenori Ikemoto 《Journal of human genetics》1992,37(4):271-283
Summary In order to examine expression of the Tn antigen on erythroid cells from a patient with Tn syndrome, we applied a selective two phase liquid culture system for human erythroid progenitors in peripheral blood. The cells were analyzed with flow cytometry employing an anti-Tn antibody and a lectin ofVicia villosa which recognizes only the Tn determinant. In the second phase, the Tn antigen was expressed on the cultured cells from the patient on day 3 and Tn-positive cells reached 62.7% on day 9. On the other hand, Tn-positive cells were not detected in the volunteer's cultured cells. When the patient's cells were co-cultured with the cells from a healthy voluteer, the percentage of Tn-positive cells was much lower than the expected value, suggesting that the normal cells suppressed the expression of Tn antigen on the patient's cells. 相似文献
99.
Martina Adler Frank Rittig Stefan Becker Harald Pasch 《Macromolecular chemistry and physics.》2005,206(22):2269-2277
Summary: The chromatographic analysis of hydrophilic copolymers is complicated due to the fact that in most cases aqueous eluents must be used. In aqueous eluents different polar and ionic effects may disturb the selective interactions between the macromolecules and the stationary phase making it impossible to separate such copolymers with regard to chemical composition. Therefore, 2D chromatography combining a separation according to composition with a separation according to molar mass has been applied mostly to polymers that are soluble in organic solvents. The present contribution describes experimental approaches to analyze such hydrophilic copolymers by 2D‐chromatography. For a model polymer system resulting from the copolymerization of methacrylic acid and a poly(ethylene glycol) macromonomer, it is shown that different analytical techniques including SEC, LC‐CC, MALDI‐TOF MS and 2D chromatography can be used to analyze the different parameters of molecular heterogeneity of such copolymers.
100.
Objective To study on adsorption effect of cadusafos and atropine sulfate by hemoperfusion.Method Hemoperfusions were performed for sheep blood samples with cadusafos and atropineby through imitated extracorporeal closed circulating perfusion apparatus.Residual cadusafos was determined by gas chromatography and residual atropine was determined by high performance liquid chromatography.Result Dose of adsorption agent was 0.5,1.0 and 1.5 g,respectively.Two hours after hemoperfusion with membrane coated activated charcoal,clearance rate of cadusafos in 3 groups all exceeded 90%.and clearance rate of atropine sulfate was 61.9%,84.9%,88.9%,respectively.One and a half hours after hemoperfusion with HA230 absorption resin,clearance rate of eadusafos in 3 groups all exceeded 90%,and clearance rate of atropine sulfate was 88.0%,97.2%,98.4%,respectively.Three hours after hemoperfusion with membrane coated activated charcoal,The concentration ratio of cadusafos and atropine sulfate in blood promoted to 10.1 times,and the ratio was 6.7 times after hemoperfusion with HA230 absorption resin.Conclusion It suggested that cadusafos were mostly removed from blood after 1.5~2.0hours hemoperfusion with membrane activated charcoal or HA230 absorption resin.The concentration ratio of cadusafos and atropine sulfate in blood will increased after hemoperfusion. 相似文献