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31.
DL?MagerEmail author AD?Haffajee PM?Devlin CM?Norris MR?Posner JM?Goodson 《Journal of translational medicine》2005,3(1):27
Background
The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls. 相似文献32.
Amy C. Young Michelle Chavez Troy A. Giambernardi Vicki Mattern John R. McGill J. Mansel Harris Michael F. Sarosdy Parul Patel Alan Y. Sakaguchi 《Somatic Cell and Molecular Genetics》1997,23(4):275-286
The ends of mammalian chromosomes terminate in structures called telomeres. Recently a human telomere repeat binding factor
(TRF1) that binds the vertebrate TTAGGG telomeric repeat in situ was isolated by Chong et al. (1). TRF1 regulates telomere
length (2), which is often altered in cancer cells. To understand their genetic organization, TRF1 genes were localized to
human chromosomes 13 cen, 21cen, and Xq13 by analysis of human monochromosomal hybrids, and by fluorescent in situ hybridization.
We also confirmed the recent localization of a human TRF1 gene to chromosome 8, and provide evidence that this locus is alternatively
spliced. In contrast to the TRF1 genes on chromosomes 8 and X, the chromosomes 13 and 21 TRF1 genes contained a 60 bp deletion
in the coding region. The results suggest that two distinct forms of TRF1 are expressed and that the TRF1 gene family includes
at least three pseudogenes whose dispersal in the human genome may have occurred via cDNA intermediates. 相似文献
33.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
34.
35.
Ramesh Patel Michael Lenczyk Raafat S. Hannallah Willis A. McGill 《Journal canadien d'anesthésie》1994,41(9):771-774
Most patients undergoing general anaesthesia are apnoeic during laryngoscopy and tracheal intubation. This study determined the time until the onset of desaturation following preoxygenation in apnoeic infants, children, and adolescents. Fifty ASA physical status I patients, 2 days to 18 yr of age, were studied. The patients were stratified into one of five groups according to age: Group I, 0–6 mo; Group II, 7–23 mo; Group III 2–5 yr; Group IV, 6–10 yr; and Group V, 11–18 yr. Following induction of anaesthesia with halothane via mask or intravenous barbiturates, the ability of the anaesthetist to ventilate the lungs via the mask was ascertained and paralysis was accomplished with vecuronium 0.1 mg · kg?1. Manual mask ventilation was maintained with oxygen and halothane. When end-tidal N2 decreased below 3% (minimum time two minutes), the face mask was removed. The time between the removal of the face mask and a decrease in oxygen saturation (SpO2 from 99–100% to 90% was measured. Manual ventilation was then resumed and the trachea intubated. Desaturation started earlier in infants than in two-to five-year-old children (96.5 ± 12.7 sec vs 160.4 ± 30.7 sec, P < 0.0001). Children became desaturated faster than adolescents (160.4 ± 30.7 vs 382.4 ± 79.9 sec, P < 0.0001). The time required to reach 90% saturation correlated well with age by linear regression analysis (r2 = 0.88, P < 0.0001). We conclude that the time to onset of desaturation following pre-oxygenation with mask ventilation increases with age in healthy apnoeic children. Adolescents can tolerate apnoea for longer than children, and infants exhibit desaturation faster than children. 相似文献
36.
The purpose of this study was to investigate the force-velocity (F/) relationship for the erector spinae muscles in submaximal activation movements, with particular attention to their response during lengthening movements and at lower shortening contraction velocities. Dynamic models that predict lower back muscle forces require reasonable representations of the modulating effect of instantaneous velocity. Ten males were observed performing trunk flexion and extension in the sagittal plane under constant load. Contraction velocities were measured as the first derivative from a devise sensitive to changes in spine curvature, and controlled by a visual feedback system while a constant load was applied through a chest harness. The erector spinae exhibited a yielding phenomenon which causes an abrupt drop in force during constant velocity stretching under constant, submaximal, stimulation. The findings were consistent with previous isovelocity muscle lengthening experiments. Yielding appeared dependent on the level of load/activation supporting the theory of a state-variableF/ relationship. The eccentric behaviour of the lower erectors (L3) seemed independent of velocity and length, while that of the upper erectors (T9) showed a dependence on length. At lower concentric velocities, concavity in torque-velocity curves was noted after a threshold velocity. The findings of this study strongly reinforce the notion that theF/ length relationship is not a continuous hyperbolic relationship during muscle shortening and that the commonly modelled force augmentation effect of lengthening is incorrect, at least for submaximal activation of the extensors of the lower back. 相似文献
37.
Selective neck dissections for squamous carcinoma of the upper aerodigestive tract: patterns of regional failure. 总被引:7,自引:0,他引:7
R M Byers G L Clayman D McGill T Andrews R P Kare D B Roberts H Goepfert 《Head & neck》1999,21(6):499-505
BACKGROUND: Surgeons have been using selective neck dissections in the treatment of squamous carcinoma of the upper aerodigestive tract for over 20 years. To date, no data is available that can answer the question "What are the patterns of failure in the neck following a selective neck dissection and is a selective neck dissection a reliable procedure for metastatic disease?" METHODS: To answer this question, the medical records of all patients with squamous carcinoma of the oral cavity, oropharynx, larynx, and hypopharynx treated at The University of Texas M. D. Anderson Cancer Center from January 1, 1985-December 31, 1990, with a selective neck dissection were reviewed. Five hundred seventeen neck dissections were analyzed: suprahyoid (41), supraomohyoid (284), and anterolateral (192). The end point of the study was regional failure and survival. RESULTS: Regional recurrence in patients treated with a suprahyoid dissection was 43% with pathologically positive nodes. The regional recurrence in the patients treated with a supraomohyoid neck dissection was 1.9% with pathologically negative nodes, 35.7% with path N1 without postoperative radiation therapy, and 5.6% with postoperative radiation therapy. The neck staged pathologically N2B failed with and without postoperative radiation, 8.3% and 14%, respectively. Thirteen percent of the anterior/lateral neck dissections failed regionally. If multiple pathologically positive nodes (N2B) were present, the regional failure with postoperative radiation was 30% and 33.3% without postoperative radiation. CONCLUSION: The results of this retrospective study suggest that a selective neck dissection is a satisfactory staging procedure and is a definitive operation if all the nodes are pathologically negative. However, if a node is found to be invaded with cancer, the use of postoperative radiation is advisable. 相似文献
38.
Falloon IR McGill CW Matthews SM Keith SJ Schooler NR 《The Journal of psychotherapy practice and research》1996,5(1):45-56
The NIMH Treatment Strategies in Schizophrenia (TSS) collaborative study group investigated the efficacy of antisychotic drug maintenance strategies involving reduced medication exposure in interaction with applied and supportive family management for the long-term treatment of schizophrenia. Therapy was provided at five centers by 25 clinicians who did not participate in the development of the therapies. They were trained by two of the authors, I.R.H.F and C.W.M, in applied family management, a homebased treatment derived from the behavioral family therapy developed by them. Clinicians' characteristics, selection, and training methods, as well as patient rehospitalization rates, are reported for the two family management conditions. The TSS study represents a bridge between the development of a novel therapy and its dissemination in general clinical practice. 相似文献
39.
Zusammenassung In der vorliegenden Studie sollte untersucht werden, ob die vonPetrovic, Lavergne undStutzmann vorgeschlagene Kategorisierung des mandibulären Wachstumspotentials für die Behandlung mit dem Funktionsregler Geltung hat. Dazu wurden die Fernröntgenaufnahmen von 140 Patienten der Angle-Klasse II nach zirka zweijähriger Behandlung mit Funktionsreglern analysiert. Im Vergleich zu 133 unbehandelten Kindern mit Angle-Klasse II trat in fast allen Rotationsgruppen eine signifikant größere Zunahme der Unterkiefergesamtlänge ein. Zwischen der Kategorie 2 mit niedrigem Wachstumpotential und Kategorie 5 mit hohem Wachstumspotential wurden keine signifikant unterschiedlichen Zunahmen der Unterkieferlänge festgestellt.
Summary The results of the study show whether the classification of mandibular growth potential, as proposed by Petrovic, Lavergne and Stutzmann has any influence on the treatment with a function regulator. X-rays of 140 class II patients were analysed after a treatment time of approximately 2 years. In comparison with 133 class II children without any treatment, a significant increase of the overall mandibular length was observed in almost all children treated. There was no significant difference in the increase of mandibular length between category 2 (low growth potential) and category 5 (high growth potential).相似文献
40.