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131.
Cássio do Nascimento Rodrigo Edson Santos Barbosa João Paulo Mardegan Issa Evandro Watanabe Izabel Yoko Ito Rubens Ferreira de Albuquerque Junior 《Clinical oral implants research》2009,20(6):571-577
Aims: To evaluate the checkerboard DNA–DNA hybridization method for detection and quantitation of bacteria from the internal parts of dental implants and to compare bacterial leakage from implants connected either to cast or to pre-machined abutments.
Materials and methods: Nine plastic abutments cast in a Ni–Cr alloy and nine pre-machined Co–Cr alloy abutments with plastic sleeves cast in Ni–Cr were connected to Branemark-compatible implants. A group of nine implants was used as control. The implants were inoculated with 3 μl of a solution containing 108 cells/ml of Streptococcus sobrinus . Bacterial samples were immediately collected from the control implants while assemblies were completely immersed in 5 ml of sterile Tripty Soy Broth (TSB) medium. After 14 days of anaerobic incubation, occurrence of leakage at the implant–abutment interface was evaluated by assessing contamination of the TSB medium. Internal contamination of the implants was evaluated with the checkerboard DNA–DNA hybridization method.
Results: DNA–DNA hybridization was sensitive enough to detect and quantify the microorganism from the internal parts of the implants. No differences in leakage and in internal contamination were found between cast and pre-machined abutments. Bacterial scores in the control group were significantly higher than in the other groups ( P <0.05).
Conclusion: Bacterial leakage through the implant–abutment interface does not significantly differ when cast or pre-machined abutments are used. The checkerboard DNA–DNA hybridization technique is suitable for the evaluation of the internal contamination of dental implants although further studies are necessary to validate the use of computational methods for the improvement of the test accuracy. 相似文献
Materials and methods: Nine plastic abutments cast in a Ni–Cr alloy and nine pre-machined Co–Cr alloy abutments with plastic sleeves cast in Ni–Cr were connected to Branemark-compatible implants. A group of nine implants was used as control. The implants were inoculated with 3 μl of a solution containing 10
Results: DNA–DNA hybridization was sensitive enough to detect and quantify the microorganism from the internal parts of the implants. No differences in leakage and in internal contamination were found between cast and pre-machined abutments. Bacterial scores in the control group were significantly higher than in the other groups ( P <0.05).
Conclusion: Bacterial leakage through the implant–abutment interface does not significantly differ when cast or pre-machined abutments are used. The checkerboard DNA–DNA hybridization technique is suitable for the evaluation of the internal contamination of dental implants although further studies are necessary to validate the use of computational methods for the improvement of the test accuracy. 相似文献
132.
Priming effects in a letter-by-letter reader depend upon access to the word form system 总被引:1,自引:0,他引:1
Several types of cognitive and neuropsychological evidence suggest that priming effects on such implicit memory tests as word identification are mediated by a pre-semantic visual word form system that can operate independently of episodic memory. We investigate priming in a letter-by-letter reader, P.T., whose pattern of performance on neuropsychological tests indicates preservation of the word form system. Experiment 1 revealed robust priming on a word identification test following letter-by-letter study of target words, despite P.T.'s great difficulty in identifying non-studied words. Experiment 2 showed that the priming effect was modality specific whereas Experiment 3 indicated that recall of previously studied words was not modality specific, thus indicating that the observed priming could not be attributed to explicit memory strategies. Experiment 4 revealed no priming of illegal nonwords on a letter identification test. The results support the notion that priming on the word identification test depends on access to the word form system. 相似文献
133.
Male-to-female (M-F) transsexuals differ consistently from female-to-male (F-M) transsexuals in their sociodemographic characteristics, cross-gender and sexual history and the degree to which personality disorder is concomitant to their transsexuality. As a group, female-to-male transsexuals are more homogeneous. Both groups are impaired in their mental functioning, but the male-to-female population is more mentally disordered. In a comparison between Dutch transsexuals and their Belgian counterparts, the latter were shown to have more mental problems. 相似文献
134.
Ricardo Ferreira Bento Rubens Vuono De Brito Tanit Ganz Sanchez Aroldo Miniti 《Otolaryngology--head and neck surgery》2002,127(5):437-441
OBJECTIVE: We conducted a prospective analysis of 22 patients with small vestibular schwannoma and useful hearing who were operated on via a transmastoid retrolabyrinthine approach between January 1994 and March 1999. Patients and Methods: The average age was 35 years, and there were 14 females and 8 males. All patients had unilateral tumors, with 10 of them occurring in the right ear and 12 occurring in the left ear. The following parameters were included in our protocol: total removal of the tumor, intraoperative difficulties or complications, immediate postoperative complications, facial score 10 days and 3 months after the surgery, and audiologic evaluation 90 days after the surgery. RESULTS: A good exposure of the internal auditory canal was possible in 19 cases. In 3 patients we had to change the approach to a translabyrinthine one to achieve total removal of the tumor in all patients. Hearing was preserved at the same preoperative levels in 31% of the cases. CONCLUSIONS: The retrolabyrinthine approach offered security to the facial nerve, no morbidity, and good percentage of hearing preservation. It is also easily changeable to a translabyrinthine approach when more exposure is necessary. 相似文献
135.
Breast MR imaging with loop-gap resonators 总被引:1,自引:0,他引:1
Breast images obtained at 1.5 T using a loop-gap resonator pair as both the excitation and detection device are presented. The efficiency of this approach is high, as judged by the low level of radio frequency (RF) power required to obtain a 90 degree pulse and the uniformity of the RF field within the resonator pair. A modification of the pair geometry provides for reasonable observation of the tissues through the chest wall and laterally to the axillae. 相似文献
136.
M. J. Bradburn D. G. Altman P. Smith I. S. Fentiman R. D. Rubens 《British journal of cancer》1998,77(11):1944-1949
The aim of this retrospective cohort study was to investigate whether survival of patients with breast cancer has changed over the period 1975-89. A total of 2604 women diagnosed as having invasive breast cancer at a clinical oncology unit in London were followed up for between 5 and 20 years. Patients were divided into four groups according to menstrual status (pre or post) and the staging of cancer (operable or inoperable). For each group, survival from diagnosis was compared between three consecutive 5-year cohorts, both with and without adjustments made for relevant prognostic factors. No temporal patterns were found in patients with inoperable cancer, in whom the survival rate was consistently low. Of women with operable cancers, differences were seen only among post-menopausal women, for whom the best survival patterns were seen in patients diagnosed between 1985-89. This is probably due to tamoxifen being commonly prescribed as adjuvant treatment for this cohort of patients. We cannot explain an apparently worse survival in the group of patients presenting in the early 1980s compared with that observed in the late 1970s. 相似文献
137.
Mitani S Kamata H Fujiwara M Aoki N Okada S Watanabe M Tango T Mori S 《Pathology international》2007,57(7):430-436
Mutations in p53 gene exons 5-9 were studied in 44 non-Hodgkin's lymphomas (NHL) consisting of 35 B-NHL and 9 T-NHL. Missense mutations were found in two diffuse large B-cell lymphomas (DLBL) and one peripheral T-cell lymphoma (unspecified). Double transversion missense and nonsense mutations were detected in one DLBL and one adult T-cell leukemia/lymphoma. Silent mutations were found in two DLBL. Detailed histomorphological study showed that cases harboring p53 missense mutation with/without nonsense mutation tended to have larger nuclei with much more prominent nucleoli. Cytomorphometric analysis was therefore conducted by measuring the gross area of 100 lymphoma cell nuclei in 44 cases and the results were compared between lymphomas harboring p53 missense mutation with/without nonsense mutation and lymphomas harboring p53 silent mutation or lacking mutation. It was found that the lymphomas harboring p53 missense mutation with/without nonsense mutation had a highly significantly larger nuclear gross area than lymphomas with silent p53 mutation or lacking mutation (two-sample t-test, P < 0.00001; Exact Wilcoxon rank-sum test, P < 0.00001). This result suggests that p53 mutation might induce enlargement of neoplastic cell nuclei by some molecular mechanism. 相似文献
138.
Melanie F. Weingart Jacquelyn J. Roth Marianne Hutt-Cabezas Tracy M. Busse Harpreet Kaur Antoinette Price Rachael Maynard Jeffrey Rubens Isabella Taylor Xing-gang Mao Jingying Xu Yasumichi Kuwahara Sariah J. Allen Anat Erdreich-Epstein Bernard E. Weissman Brent A. Orr Charles G. Eberhart Jaclyn A. Biegel Eric H. Raabe 《Oncotarget》2015,6(5):3165-3177
Atypical teratoid rhabdoid tumor (AT/RT) is among the most fatal of all pediatric brain tumors. Aside from loss of function mutations in the SMARCB1 (BAF47/INI1/SNF5) chromatin remodeling gene, little is known of other molecular drivers of AT/RT. LIN28A and LIN28B are stem cell factors that regulate thousands of RNAs and are expressed in aggressive cancers. We identified high-levels of LIN28A and LIN28B in AT/RT primary tumors and cell lines, with corresponding low levels of the LIN28-regulated microRNAs of the let-7 family. Knockdown of LIN28A by lentiviral shRNA in the AT/RT cell lines CHLA-06-ATRT and BT37 inhibited growth, cell proliferation and colony formation and induced apoptosis. Suppression of LIN28A in orthotopic xenograft models led to a more than doubling of median survival compared to empty vector controls (48 vs 115 days). LIN28A knockdown led to increased expression of let-7b and let-7g microRNAs and a down-regulation of KRAS mRNA. AT/RT primary tumors expressed increased mitogen activated protein (MAP) kinase pathway activity, and the MEK inhibitor selumetinib (AZD6244) decreased AT/RT growth and increased apoptosis. These data implicate LIN28/RAS/MAP kinase as key drivers of AT/RT tumorigenesis and indicate that targeting this pathway may be a therapeutic option in this aggressive pediatric malignancy. 相似文献
139.
The Role of New Removable Complete Dentures in Stimulated Salivary Flow and Taste Perception 下载免费PDF全文
140.