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81.
82.
CE Ferreira SG Grossi AB Novaes RG Dunford EJ Feres-Filho 《Canadian Metallurgical Quarterly》1997,17(3):250-259
The aim of this study was to determine the effect of subgingival scaling and root planing on healing of the distal surface of second molars following extraction of third molars. Twenty-eight patients with contralateral erupted third molars and pocket depths greater than or equal to 3 mm on the distal surface of the second molars participated in this study. Measurements of supragingival bacterial plaque, bleeding on probing, pocket depth, and relative attachment level were performed at baseline and 2 months after treatment. Extraction of contralateral third molars was carried out simultaneously. The experimental site received thorough scaling and root planing of the distal surface of the second molar, while the control site received extraction alone. Experimental sites showed significant improvement in all clinical parameters assessed compared to the control sites. In conclusion, periodontal lesions on the distal of second molars can be significantly improved following scaling and root planing after extraction of third molars. 相似文献
83.
AV Feofanov VA Ole?nikov AB Tuzikov AI Ianul' EIu Kriukov NV Bovin IR Nabiev 《Canadian Metallurgical Quarterly》1997,23(11):910-918
Neoglycoconjugates based on polyacrylamide and sialic acid with N-acetylneuraminic acid or sialooligosaccharides as side chains were studied by surface-enhanced Raman scattering (SERS) spectroscopy. It had previously been found that these polymers can effectively inhibit influenza virus adhesion. This study revealed the possibility to evaluate, based on the intensity of SERS signals, the overall availability for interaction and the conformational freedom of sialic acid residues in glycoconjugates. The dependence of these two factors on the structure and density of sialylated side chains was studied. The uniformity of distribution of sialylated side chains in conjugates was shown. Comparison of the results of the SERS spectroscopic study of the conjugates and the data on their inhibitory effect on the adhesion of specific strains of influenza virus allowed the identification of the conjugates for which the availability and conformational freedom of sialic acid are the main factors determining their inhibitory properties. A conclusion was also reached about the predominance of one of the mechanisms (competitive inhibition or steric stabilization) in the inhibitory properties of the specific conjugates. 相似文献
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I. N. Datsenko E. S. Klochko L. A. Baranchukova O. F. Ammosova Z. G. Vasilenko V. P. Koleushko 《Fibre Chemistry》1989,20(3):219-220
Conclusions The fundamental possibility of preparing heat-set polycaproamide yarns of 4 tex linear density which conform to the requirements of technical conditions has been demonstrated.Heat-set yarns which have been prepared with combination of the heat-setting and rewinding processes have a more uniform shrinkage by package layers than when they are treated with hot water or steam on rigid packages.Combining the processes of heat-setting and rewinding will make it possible to shorten the technological process of manufacturing textile polycaproamide yarns.Translated from Khimicheskie Volokna, No. 3, pp. 43–44, May–June, 1988. 相似文献
86.
H K?llstr?m MS Islam PO Berggren AB Jonsson 《Canadian Metallurgical Quarterly》1998,273(34):21777-21782
Neisseria gonorrhoeae and Neisseria meningitidis are Gram-negative bacterial pathogens that infect human mucosal epithelia. Type IV pilus-mediated adherence of these bacteria is a crucial early event for establishment of infection. In this work, we show that the type IV pili transduce a signal into the eucaryotic host cell. Purified adherent pili, but not pili from a low binding mutant, trigger an increase in the cytosolic free calcium ([Ca2+]i) in target epithelial cells, a signal known to control many cellular responses. The [Ca2+]i increase was blocked by antibodies against CD46, a putative pilus receptor, suggesting a role for this protein in signal transduction. Pilus-mediated attachment was inhibited by depletion of host cell intracellular Ca2+ stores but not by removal of extracellular Ca2+. Further, kinase inhibition studies showed that pilus-mediated adherence is dependent on casein kinase II. In summary, these data reveal a novel function of the type IV pili, namely induction of signal transduction pathways in host cells. 相似文献
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88.
MK Kraft AB Rothbard TR Hadley AT McLellan DA Asch 《Canadian Metallurgical Quarterly》1997,154(9):1214-1219
OBJECTIVE: Previous research has suggested that support services supplementing methadone maintenance programs vary in their cost-effectiveness. This study examined the cost-effectiveness of varying levels of supplementary support services to determine whether the relative cost-effectiveness of alternative levels of support is sustained over time. METHOD: A group of 100 methadone-maintained opiate users were randomly assigned to three treatment groups receiving different levels of support services during a 24-week clinical trial. One group received methadone treatment with a minimum of counseling, the second received methadone plus more intensive counseling, and the third received methadone plus enhanced counseling, medical, and psychosocial services. The results at the end of the trial period have been published elsewhere. This article reports the results of an analysis at a 6-month follow-up. RESULTS: The follow-up analysis reaffirmed the preliminary findings that the methadone plus counseling level provided the most cost-effective implementation of the treatment program. At 12 months, the annual cost per abstinent client was $16,485, $9,804, and $11,818 for the low, intermediate, and high levels of support, respectively. Abstinence rates were highest, but modestly so, for the group receiving the high-intensity, high-cost methadone with enhanced services intervention. CONCLUSIONS: This study suggests that large amounts of support to methadone-maintained clients are not cost-effective, but it also demonstrates that moderate amounts of support are better than minimal amounts. As funding for these programs is reduced, these findings suggest a floor below which supplementary support should not fall. 相似文献
89.
VC Dias KL Madsen KE Mulder M Keelan RW Yatscoff AB Thomson 《Canadian Metallurgical Quarterly》1998,43(10):2227-2236
The immunosuppressive drugs rapamycin (Rap) and cyclosporine A (CsA) are used clinically to modify or abolish immune-mediated functions. This study examined the effect of orally administered regimens of Rap, CsA, and a combination of Rap/CsA on intestinal function in male New Zealand white rabbits. Animals received oral doses of CsA (15 mg/kg/body weight/day), low-dose (LD) and high-dose (HD) Rap (0.25 or 1 mg/kg/body wt/day, respectively), or Rap/CsA (0.25 and 5 mg/kg/body wt/day, or 0.5 and 5 mg/kg/body wt/day, respectively) for 20 days. We measured in vitro uptake of nutrients and permeability, and morphometric measurements in the jejunum and ileum were made. Animals receiving HD-Rap or HD-Rap/CsA had decreased food intake, body weight, and intestinal weight, when compared with LD-Rap, LD-Rap/CsA, CsA, or controls. The maximal transport rate (Vmax) for the active jejunal uptake of D-glucose was increased in HD-Rap and CsA, but not in the HD-Rap/CsA-treated animals. The jejunal Vmax of D-glucose in the LD-Rap- or -Rap/CsA-treated animals was no different from controls. In the HD-Rap- and HD-Rap/ CsA-treated animals, jejunal rates of uptake of stearic, linoleic, and linolenic acids were reduced when compared with controls. Jejunal and ileal permeability (as assessed by the passive uptake of L-glucose, tissue conductance, and mucosal-to-serosal flux of [3H]inulin) was increased in animals treated with HD-Rap or HD-Rap/CsA, when compared with CsA or controls. These parameters of permeability were no different at lower doses of Rap or Rap/CsA. The jejunal and ileal villous surface area was increased in CsA, but decreased in HD-Rap or HD-Rap/CsA animals. Thus, HD-Rap given alone or in combination with CsA reduced body weight gain, in part due to reduced food intake and malabsorption of lipids, which was due at least in part to reduced intestinal surface area. The relevance of these findings to patients undergoing chronic immunosuppressive drug therapy needs to be established. 相似文献
90.
FM Scott AM Treston GL Shaw I Avis J Sorenson K Kelly EC Dempsey AB Cantor M Tockman JL Mulshine 《Canadian Metallurgical Quarterly》1996,14(2-3):239-251
Monitoring respiratory epithelial biology may reveal individuals with incipient lung cancer. The expression of neuroendocrine (NE) markers in pulmonary epithelium is thought to be central to lung development, repair of injury and may contribute to carcinogenesis. In this study, we evaluate several candidate NE markers to determine the feasibility of prospective analysis of clinical specimens. The potential NE markers include the enzyme L-DOPA decarboxylase (DDC), the neuropeptide gastrin releasing peptide (GRP), and peptidyl-glycine alpha-amidating monooxygenase (PAM), the bifunctional enzyme responsible for the final bioactivation step of many neuropeptides. A comparison of PAM activity and DDC levels in 30 lung cancer cell lines indicated that peptide amidating activity may be an indicator of NE status. Bronchoalveolar lavage (BAL) fluid from subjects at risk of developing second primary lung cancer and from volunteers was obtained. The activity of the first PAM enzyme, peptidylglycine alpha-hydroxylating monooxygenase (PHM), ranged from not detectable to 507 pmol/h/mg protein in 57 specimens. The second PAM enzyme, peptidylamidoglycolate lyase (PAL), ranged from not detectable to 414 pmol/h/mg protein in 56 specimens. Using cluster analysis by the average linkage method, a group of enzyme values with PHM greater than 230 pmol/h/mg protein was determined. Long-term follow-up of these patients for new second primary lung cancers may help to determine the potential predictive value of PAM detected in the BAL fluid. 相似文献