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31.
Subject case marking and verb morphology in normally developing and specifically language-impaired children 总被引:1,自引:0,他引:1
Recent theories of language development propose a direct relationship between children's use of verb morphology and their use of subject case pronouns. Such proposals might contribute to an understanding of specifically language-impaired (SLI) children's difficulties. These children's extraordinary problems with verb morphology are well documented, and preliminary evidence indicates frequent pronoun case errors (e.g., her for she) in their speech. Thus, it is possible that a collection of difficulties may be linked to a common source in these children. The objectives of this study were to determine: (a) whether subject case marking, as well as verb morphology was more limited in the speech of a group of SLI children than in the speech of a younger group of normally developing (ND) children matched for mean utterance length; (b) whether a relationship between the use of subject case marking and the use of verb morphology existed in the speech of the ND children; and, if so, (c) whether this relationship is evident in the SLI children as well, in spite of their more limited use of these features. The results revealed that the SLI children were more limited than the ND children in the use of both subject case marking and verb morphology. However, a relationship between the two types of usage was found in both groups of children. 相似文献
32.
Douglas M. Howarth Martin T. Epstein Paul A. Thomas Leonard W. Allen Rachel Akerman Linda Lan 《European journal of nuclear medicine and molecular imaging》1997,24(12):1465-1469
The efficacy of fractionated out-patient radioiodine therapy in 38 patients with compressive symptoms due to long-standing
large multinodular goitres was assessed. The diagnosis was established by clinical assessment in addition to technetium-99m
pertechnetate thyroid scan or computed tomography scan of the thyroid and mediastinum. Oral iodine-131 therapy was administered
as a 2.22 GBq (60 mCi) cumulative dose over 4 months (555 MBq per month). All patients were monitored with serum thyroid-stimulating
hormone and free thyroxine (± free tri-iodothyronine) assays before the treatment and after each dose fraction. Clinical and
biochemical follow-up was performed on all patients and ranged from 6 to 45 months after therapy. The patients consisted of
35 female and three male patients with a median age of 59 years (range 37–87 years). Prior to treatment 20 patients were biochemically
hyperthyroid and 18 were euthyroid. Overall, 71% of patients reported a subjective improvement in compressive symptoms and
29% reported no change. Clinically assessed reduction in goitre size occurred in 92% of patients while there was no change
in 8%. At 3 months of follow-up, 31% of patients had become hypothyroid and at 18 months 66% were hypothyroid. Seven hyperthyroid
patients (35%) became euthyroid and 13 hyperthyroid patients (65%) became hypothyroid. Three patients who became hypothyroid
experienced neck soreness (transient in one patient, persistent in two patients). There were no differences in outcome between
patients who were hyperthyroid and those who were euthyroid prior to treatment. Fractionated out-patient radioiodine therapy
showed excellent short- and medium-term safety, was very well tolerated and offered a satisfactory alternative treatment to
surgery.
Received 23 May and in revised form 11 August 1997 相似文献
33.
Chromosomal aberrations in human lymphocytes induced in vitro by very low doses of X-rays. 总被引:2,自引:0,他引:2
D C Lloyd A A Edwards A Leonard G L Deknudt L Verschaeve A T Natarajan F Darroudi G Obe F Palitti C Tanzarella 《International journal of radiation biology》1992,61(3):335-343
This paper presents results of a collaborative experiment between six laboratories which examined the yields of unstable chromosomal aberrations in human lymphocytes induced in vitro by X-rays over the dose range 0-300 mGy. The work included data points of nominal doses of 0, 3, 5, 6, 10, 20, 30, 50 and 300 mGy. Cells from 24 donors were examined and a total of about 300,000 metaphases were scored. The work was undertaken to determine the limits of sensitivity of the system taking into account variations in scoring data due to inter-donor sample and inter-laboratory effects. Despite the existence of these effects, aberration yields significantly in excess of control values were seen at doses greater than 20 mGy and these were consistent with a linear extrapolation from higher doses. Below 20 mGy the observed dicentric yields were generally lower than background, but not significantly so. Excess acentric aberrations, on the other hand, and centric rings, were higher than the controls but the increase was usually not significant. It is concluded that the statistical uncertainties are such that below 20 mGy this technique cannot distinguish between a linear or a threshold model. 相似文献
34.
Justin W. Phillpott M.D. Leonard E. Swischuk M.D. Susan D. John M.D. 《Emergency radiology》1997,4(2):68-71
We reviewed plain radiographs of 215 pediatric patients with surgically proven appendicitis to study the value of plain radiography for diagnosis. 相似文献
35.
36.
The study of energetics is important to human biology because the availability and utilization of food energy influence health, survival, and reproduction. Over the last decade, human biologists, biological anthropologists, and other evolutionary scientists have increasingly come to recognize the importance of energy dynamics in shaping evolutionary processes. Thus far, different lines of energetics research have been conducted largely in isolation from one another. This thematic collection examines topics of evolutionary energetics from several different perspectives, drawing together research from human paleontology, comparative primate and mammalian biology, human population biology, and mathematical modeling. It represents a starting point for further integrative research on human evolutionary energetics. Am. J. Hum. Biol. 14: 547–550, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
37.
Congenital neoplasms of the central nervous system are extremely rare, although they have been well documented since the earliest reports from the mid-19th century. Medulloblastoma, other primitive neuroectodermal tumors, and various types of gliomas have comprised the majority of cases. This report describes a highly unusual infratentorial and supratentorial tumor presenting as a scalp mass in a neonate who experienced in utero distress. The supratentorial mass extended through a defect in the skull to the parietooccipital lobe, and the infratentorial aspect involved the 9th and 10th cranial nerves in the region of the cerebellopontine angle. A complex spindle cell neoplasm incorporating peripheral nerve sheath and vascular characteristics was further characterized by electron microscopy and immunohistochemistry. Based upon these studies, the tumor was interpreted as a congenital schwannoma with divergent vascular differentiation. The child has been tumor-free for approximately 2 years after the initial operative procedure. 相似文献
38.
Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
39.
Adjuvant therapy for adenocarcinoma of the rectum 总被引:3,自引:0,他引:3
Michael J. O'Connell M.D. Leonard L. Gunderson M.D. M.S. 《World journal of surgery》1992,16(3):510-515
Surgical resection continues to be the primary curative modality for patients with adenocarcinoma of the rectum. However, local tumor recurrence in the pelvis and/or distant metastasis may occur in spite of complete excision of grossly visible malignant disease. Surgical and pathologic staging can identify a subset of surgically treated rectal cancer patients at high risk for tumor relapse and death. Irradiation and chemotherapy have been used as adjuvant therapy in conjunction with surgery as single modalities and in combination for patients with high risk rectal cancer. Evidence from controlled clinical trials indicates a significant decrease in local tumor recurrence, and a significant improvement in disease-free and overall survival with the use of combined postoperative irradiation and chemotherapy in this setting. A current national clinical trial in the United States of America is studying whether irradiation can be combined with new chemotherapy regimens which have shown significant therapeutic benefit as surgical adjuvant therapy for patients with high risk colon cancer (5FU + levamisole) and for patients with metastatic colorectal cancer (5FU + leucovorin) to further improve the efficacy of surgical adjuvant therapy for adenocarcinoma of the rectum.
Resumen La resección quirúrgica continúa siendo la modalidad curativa primaria en pacientes con adenocarcinoma del recto. Sin embargo, la recurrencia local del tumor en la pelvis y/o las metástasis distantes puede ocurrir a pesar de la resección completa de la enfermedad maligna macroscópicamente visible. La estadificación operatoria y patológica puede indentificar un subgrupo de pacientes tratados quirúrgicamente con alto riesgo de relapso tumoral y meserte. La irradiación y la quimioterapia han sido utlizados como terapia adyuvante en unión con la cirugía como modalidades únicas y en combinación para pacientes con cáncer rectal de alto riesgo. La evidencia surgida de ensayos clínicos controlados señala una disminución significativa en las tasas de recurrencia tumoral local, y una superación significativa en las tasas globales de sobrevida y de sobrevida libre de enfermedad con el uso de la combinación postoperatoria de irradiación y quimioterapia. Un ensayo clínico nacional que se ejecute en el momento actual en los Estados Unidos investiga si la irradiación puede ser combinada con los nuevos regímenes quimioterapéuticos que han demostrado beneficio significantivo como terapia quirúrgica adyuvante en pacientes con cáncer de colon de alto riesgo (5 FU + levamisol) y en pacientes con cáncer colorrectal metastásico (5 FU + leucovorin) con el propósito de mejorar aún más la eficicacia de la terapia quirúrgica adyuvante en el adenocarcinoma del recto.
Résumé La chirurgie est le principal moyen thérapeutique de l'adénocarcinome du rectum. La récidive tumorale pelvienne et/ou à distance peut cependant se produire malgré une résection apparemment complète. Un bilan d'extension chirurgical et anatomopathologique peut identifier un sous-groupe de patients susceptible de présenter une récidive ou d'en mourir. La radio-et chimiothérapie ont été préconisées comme traitement adjuvant après l'exérèse chirurgicale, soit seule, soit combinée, chez cez patients à risque. Les résultats de plusieurs essais thérapeutiques semblent indiquer que la radio-et la chimiothérapie combinée à la chirurgie diminuent significativement le taux de récidives locales et améliorent significativement la survie globale et la survie sans maladie. Un essai actuellement en cours aux Etats-Unis étudie si la radiothérapie peut être utilement combinée avec les nouveaux régimes chimiothérapeutiques ayant fait preuve de leur efficacité chez les patients à risque (5FU + lévamisole) ou chez les patients ayant des métastases (5FU + leucovin).相似文献
40.
Effect of compressive follower preload on the flexion-extension response of the human lumbar spine. 总被引:5,自引:0,他引:5
Avinash G Patwardhan Robert M Havey Gerard Carandang James Simonds Leonard I Voronov Alexander J Ghanayem Kevin P Meade Thomas M Gavin Odysseas Paxinos 《Journal of orthopaedic research》2003,21(3):540-546
Traditional experimental methods are unable to study the kinematics of whole lumbar spine specimens under physiologic compressive preloads because the spine without active musculature buckles under just 120 N of vertical load. However, the lumbar spine can support a compressive load of physiologic magnitude (up to 1200 N) without collapsing if the load is applied along a follower load path. This study tested the hypothesis that the load-displacement response of the lumbar spine in flexion-extension is affected by the magnitude of the follower preload and the follower preload path. Twenty-one fresh human cadaveric lumbar spines were tested in flexion-extension under increasing compressive follower preload applied along two distinctly different optimized preload paths. The first (neutral) preload path was considered optimum if the specimen underwent the least angular change in its lordosis when the full range of preload (0-1200 N) was applied in its neutral posture. The second (flexed) preload path was optimized for an intermediate specimen posture between neutral and full flexion. A twofold increase in flexion stiffness occurred around the neutral posture as the preload was increased from 0 to 1200 N. The preload magnitude (400 N and larger) significantly affected the range of motion (ROM), with a 25% decrease at 1200 N preload applied along the neutral path. When the preload was applied along a path optimized for an intermediate forward-flexed posture, only a 15% decrease in ROM occurred at 1200 N. The results demonstrate that whole lumbar spine specimens can be subjected to compressive follower preloads of in vivo magnitudes while allowing physiologic mobility under flexion-extension moments. The optimized follower preload provides a method to simulate the resultant vector of the muscles that allow the spine to support physiologic compressive loads induced during flexion-extension activities. 相似文献