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51.
The aim of study was the evaluation of periodontal pockets microflora in patients with advanced periodontitis. From each subject 16-20 samples were taken using paper points. Pooled sample after 60 s. mixing was serially diluted in reduced BHI. For total cell counts and for the isolation of black pigmented anaerobes Brucella agar supplemented with 5% sheep blood, hemin, menadione, with and without Kanamycin-Vancomycin mixture and BM agar plates were used. For isolation of A. actinomycetemcomitans TSBV agar plates were used. Cultures were incubated in anaerobic chamber at 37 degrees C for 7 days and TSBV agar plates in an atmosphere of 95% air-5% CO2 at 37 degrees C for 5 days. Microorganisms were identified by Gram staining, colony morphology, fluorescence in UV-light, haemagglutination of 3% sheep erythrocytes, fermentation of sugars, production of indole, urease (API 20A), specific enzymes (Rapid ID 32A). Twenty seven subjects with clinically recognized periodontitis were examined. Microorganisms important in periodontitis were isolated from periodontal pockets of almost all examined subjects. The number of bacteria obtained from the sample of one patient ranged from 1 x 10(4) CFU/ml to 3,6 x 10(6) CFU/ml. Porphyromonas gingivalis was identified in the samples taken from 17 patients, Prevotella intermedia-19, Actinobacillus actinomycetemcomitans -11, Fusobacterium nucleatum-9, Peptostreptococcus spp.-22.  相似文献   
52.
PURPOSE: Transformation of fast-twitching skeletal muscles to slow-twitching, slowly fatigable muscles has become of clinical interest in the recent past. Transposition and transformation of the gracilis muscle to use it as a substitute for a resected or defected anal sphincter (graciloplasty) have been reported as achieving promising results in the treatment of fecal incontinence caused by sphincter defects or following abdominoperineal anorectal excision for cancer. METHOD: This experimental study used a canine model and the sartorius muscle to evaluate the functional efficiency of two different configurations of the muscle loop to compare the presently applied transformation program (8 weeks) with a shorter (5 weeks) protocol. In six beagle dogs, both sartorius muscles were wrapped around two stomas, either in an alpha fashion or in the so-called split-sling technique. Muscle transformation was achieved by controlled neuromuscular stimulation either during eight (Program A) or five weeks (Program B). After completion of the transformation period, the function of the muscle slings was evaluated by manometry, and histomorphologic evaluation of the sartorius muscles was performed. RESULTS: It was shown that muscle transformation led to a slowly fatigable muscle that made it possible to perform continuos (tetanic) contraction, regardless of the configuration or the duration of the transformation. Median pressures created by these muscles also did not differ significantly. In accordance with these functional findings, the histologic evaluation showed the typical, significant increase of Type I fibers in both muscle slings and following both transformation protocols. Although the decrease of fast-twitching Type II fibers was more pronounced following the conventional (8 weeks) program, this finding did not influence the functional results. CONCLUSIONS: Results of our experiment indicate the possibility for using a shorter transformation protocol for transformation of the gracilis muscle during graciloplasty in the clinical setting. Furthermore, the efficacy and safety of the modified (split-sling) wrap technique was demonstrated.  相似文献   
53.
Assuming that the chemical reactions used to synthesize a combinatorial library member are successful, then knowledge of the specific reaction sequence is equivalent to knowing the member's chemical identity. Because the determination of chemical identity is typically not automatable and requires a substantial amount of material, schemes that encode a member's reaction history onto the reaction platform are of value. The primary benefits of encoding are relational nomenclature (all methods) and automated handling (some methods). Encoding methods evaluated to date are spatial, graphical, chemical, spectrometric, electronic, and physical.  相似文献   
54.
Aspergillus fumigatus possesses two catalases (described as fast and slow on the basis of their electrophoretic mobility). The slow catalase has been recognized as a diagnostic antigen for aspergillosis in immunocompetent patients. The antigenic catalase has been purified. The enzyme is a tetrameric protein composed of 90-kDa subunits. The corresponding cat1 gene was cloned, and sequencing data show that the cat1 gene codes for a 728-amino-acid polypeptide. A recombinant protein expressed in Pichia pastoris is enzymatically active and has biochemical and antigenic properties that are similar to those of the wild-type catalase. Molecular experiments reveal that CAT1 contains a signal peptide and a propeptide of 15 and 12 amino acid residues, respectively. cat1-disrupted mutants that were unable to produce the slow catalase were as sensitive to H2O2 and polymorphonuclear cells as the wild-type strain. In addition, there was no difference in pathogenicity between the cat1 mutant and its parental cat1+ strain in a murine model of aspergillosis.  相似文献   
55.
Comparative genomic hybridization (CGH) was used to detect copy number changes of DNA sequences in the Ewing family of tumours (ET). We analysed 20 samples from 17 patients. Fifteen tumours (75%) showed copy number changes. Gains of DNA sequences were much more frequent than losses, the majority of the gains affecting whole chromosomes or whole chromosome arms. Recurrent findings included copy number increases for chromosomes 8 (seven out of 20 samples; 35%), 1q (five samples; 25%) and 12 (five samples; 25%). The minimal common regions of these gains were the whole chromosomes 8 and 12, and 1q21-22. High-level amplifications affected 8q13-24, 1q and 1q21-22, each once. Southern blot analysis of the specimen with high-level amplification at 1q21-22 showed an amplification of FLG and SPRR3, both mapped to this region. All cases with a gain of chromosome 12 simultaneously showed a gain of chromosome 8. Comparison of CGH findings with cytogenetic analysis of the same tumours and previous cytogenetic reports of ET showed, in general, concordant results. In conclusion, our findings confirm that secondary changes, which may have prognostic significance in ET, are trisomy 8, trisomy 12 and a gain of DNA sequences in 1q.  相似文献   
56.
Morgagni hernias are the least common form of diaphragmatic hernias. Although they are congenital, most of them are not diagnosed until later in life. The indication for surgery is based on the patient's symptoms or on the radiological evidence of incarcerated tissue, and until quite recently involved a laparotomy or thoracotomy. Laparoscopy not only permits the suspected diagnosis to be confirmed--which is otherwise often difficult--but also makes it possible to close the hernia site by suturing. For improved security, the hernia site is augmented by fixing in place a non-absorbable mesh. The operative technique employed is described.  相似文献   
57.
The modulatory role of locally produced cyclooxygenase products and endothelium-derived nitric oxide in controlling vascular tone was investigated in bovine intra-mammary artery. Vascular reactivity initiated by vasoactive compounds, endothelin-1 (ET-1), bradykinin (BK), and substance P (SP) was measured isometrically in an isolated tissue bath. The effects of a cyclooxygenase inhibitor, indomethacin (10(-5) M) and an inhibitor of nitric oxide production, N omega-Nitro L-Arginine (L-NNA: 3 x 10(-4) M) were determined during agonist-mediated responses. Indomethacin alone markedly enhanced vascular contraction produced by ET-1, while L-NNA did not. Inhibition of endothelium-derived nitric oxide synthesis by L-NNA, however, significantly attenuated BK- and SP-induced vascular relaxations, whereas indomethacin had slight influence. The potentiation between indomethacin and L-NNA in regulating vasomotor tone was not observed in this vascular bed. Thus, it appeared that both the cyclooxygenase and endothelium-derived nitric oxide pathways participated in modifying vascular reactivity. Domination of one pathway over the other depended upon the agonist used to stimulate vascular tissue.  相似文献   
58.
Several dimethylsilane tetramines [homologs of spermine with an Si(CH3)2 group in the central carbon chain], a carbon analog of the dimethylsilane tetramines [containing C(CH3)2 instead of Si(CH3)2] and a dimethylsilane hexamine were studied with regard to their cytotoxic activity and their ability to interact with double-stranded DNA. All polyamine analogs exerted cytostatic effects to several cell lines at micromolar concentrations. Their ability to condense DNA was comparable to and their ability to displace ethidium bromide from binding to DNA was superior to that of spermine. Their cytostatic effect was not correlated with the depletion of cellular spermidine concentrations. It is suggested that the new polyamine analogs act mainly by displacing spermidine from binding sites which are essential for the promotion of cell growth.  相似文献   
59.
60.
In order to observe the transport ability of peritoneum to small molecular substances, peritoneal equilibration test (PET) was performed in 52 CAPD patients. By analysing the relationship between peritoneal transport function and dialysis adequacy, we found the average urea KT/V and Cr were significantly lower in high and low transport groups (n = 6 and n = 2) than in high average and low average groups (n = 35 and n = 9). According to the results of PET, we adjusted the dialysis program of 11 patients and the dialysis adequacy was markedly improved. We concluded that PET was helpful for selecting and adjusting CAPD program, and discussed some questions which should be payed more attention in PET operation.  相似文献   
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