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51.
William S Kremen Larry J Seidman Stephen V Faraone Ming T Tsuang 《Journal of the International Neuropsychological Society》2003,9(1):79-88
Phonemic and semantic fluency involve the capacity to generate words beginning with particular letters or belonging to particular categories, respectively. The former has been associated with frontal lobe function and the latter with temporoparietal function, but neuroimaging studies indicate overlap of underlying neural networks. Schizophrenia patients may experience disproportionate semantic fluency impairment owing to abnormal semantic organization; however, executive dysfunction in schizophrenia suggests possible disproportionate phonemic fluency impairment. Moreover, little is known about the diagnostic specificity of either verbal fluency deficit to schizophrenia or their stability over time. We examined 83 schizophrenia patients, 15 bipolar disorder patients, and 83 normal controls. Both fluency types were impaired in schizophrenia patients. Schizophrenia patients as a whole manifested disproportionate semantic fluency impairment relative to bipolar disorder patients, but only a subset of schizophrenia patients manifested disproportionate semantic fluency impairment relative to controls. Few characteristics, except to some extent paranoid-nonparanoid subtype, meaningfully differentiated schizophrenia patients with and without this disproportionate impairment. Verbal fluency measures were moderately stable over a 4-year period in schizophrenia patients and controls (.48 < rs < .79). These results mirror a literature that overall suggests a small degree of disproportionate semantic fluency impairment in schizophrenia, but also some heterogeneity in fluency deficits. 相似文献
52.
Numerous advances in technology have been made in the last several years in the diagnosis and treatment of the infertile man. Using case presentations, this article highlights these important new developments and reviews the basics of a comprehensive male infertility evaluation. The use of ultrasound as a critical, indispensable, yet noninvasive tool in the evaluation of possible male reproductive tract obstruction is discussed. Since assisted reproductive techniques (ARTs) have be come increasingly important in the management of the otherwise untreatable infertile man, specialized testing of sperm function, e.g., the sperm penetration assay (SPA), and strict morphology assessment are often useful prior to the initiation of some of these assisted reproductive procedures such as intrauterine insemination (IUI) or in vitro fertilization (IVF). Testicular touch preparation cytology and image analysis are also important additions to routine testicular biopsy for quantifying the extent of spermatogenesis. Finally, the revolutionary micromanipulation procedure of intracytoplasmic sperm injection (ICSI) has forever changed the practice of andrology by enabling men previously thought to be irreversibly infertile the chance to initiate their own biologic pregnancy. 相似文献
53.
PURPOSE: To examine the relationship between ametropia and optical aberrations in a population of 200 normal human eyes with refractive errors spanning the range from +5.00 to -10.00 D. METHODS: Using a reduced-eye model of ametropia, we tested the hypothesis that the optical system of the eye is uncorrelated with the degree of ametropia. These predictions were evaluated experimentally with a Shack-Hartmann aberrometer that measured the monochromatic aberrations across the central 6 mm of the dilated pupil in well-corrected, cyclopleged eyes. RESULTS: Optical theory predicted, and control experiments on a model eye verified, that Shack-Hartmann measurements of spherical aberration will vary with axial elongation of the eye even if the dioptric components of the eye are fixed. Contrary to these predictions, spherical aberration was not significantly different from emmetropic eyes. Root mean square of third-order aberrations, fourth-order aberrations, and total higher aberrations (third to 10th) in myopic and hyperopic eyes were also uncorrelated with refractive error. Astigmatic eyes tended to have larger total higher-order aberrations than nonastigmatic eyes. CONCLUSIONS: We conclude that a reduced-eye model of myopia assuming fixed optical parameters and variable axial length is not tenable. 相似文献
54.
Xin Hong Larry N Thibos Arthur Bradley Russell L Woods Raymond A Applegate 《Optometry and vision science》2003,80(1):15-25
Repeated measures of wavefront aberrations were taken along the line-of-sight of seven eyes using two instruments: an objective, cross-cylinder aberroscope (OA) and a Shack-Hartmann (SH) aberrometer. Both instruments were implemented on the same optical table to facilitate interleaved measurements on the same eyes under similar experimental conditions. Variability of repeated measures of individual coefficients tended to be much greater for OA data than for SH data. Although Zernike coefficients obtained from a single measurement were generally larger when measured with the OA than with the SH, the averages across five trials were often smaller for the OA. The Zernike coefficients obtained from the two instruments were not significantly correlated. Radial modulation-transfer functions and point-spread functions derived from the two sets of measurements were similar for some subjects, but not all. When average Zernike coefficients were used to determine optical quality, the OA indicated superior optics in some eyes, but the reverse trend was true if Zernike coefficients from individual trials were used. Possible reasons for discrepancies between the OA and SH measurements include difference in sampling density, quality of data images, alignment errors, and temporal fluctuations. Multivariate statistical analysis indicated that the SH aberrometer discriminated between subjects much better than did the objective aberroscope. 相似文献
55.
Larry Burd Jacob Kerbeshian Julie L. Meredith 《Journal of developmental and physical disabilities》1997,9(3):255-263
This paper reviews the association of Huntington's Disease (HD) and tic disorder or Tourette Syndrome (TS) We also present the results of a follow-up study of a male with childhood-onset TS and adult-onset HD who died at 45 years of age. The developmental course and results of neuropathologic and molecular studies of this patient are reported. This is the first case of childhood onset of TS with adult onset of HD reported who has come to autopsy. A developmental model for childhood and adult neuropsychiatric disorders is presented. 相似文献
56.
Henry M. Goodgold M.D. Rita C. Gentilcore Lynn Hendershott James W. Fletcher Larry D. Samuels 《European journal of nuclear medicine and molecular imaging》1986,12(5-6):271-273
To assess the significance of diffuse cardiac activity (DCA) seen on In-111 labeled leukocyte scans, we reviewed 87 studies performed over the last 4 years. Inflammatory cardiac conditions were seen as frequently in patients with DCA (15%) as those without (7%, P=0.3). There was a higher ratio of RBC:WBC in the final WBC preparation in the false-positive DCA group than the true positive DCA and no DCA groups. False-positive studies showing DCA are most likely due to residual blood pool activity.Presented in part, 70th annual meeting, Radiological Society of North America, Washington D.C., 25 November 1984 相似文献
57.
A 3.5-year-old boy with orbital and central nervous system extension of unilateral retinoblastoma received chemotherapy consisting of intravenous cyclophosphamide and doxorubicin and intrathecal methotrexate. Complete shrinkage of orbital tumor, phthisis bulbi,'and disappearance of intracranial metastases occurred following chemotherapy. Response of the intra-cranial tumors reflected the combined effects of cyclophosphamide and doxorubicin; the contribution of each agent could not be assessed. Cerebrospinal fluid tumor cells persisted prior to delivery of craniospinal irradiation, and were detected again 6 weeks after completion of irradiation. 相似文献
58.
Susan K. Hummel DDS Victoria Marker PhD Larry Pace DDS Michael Goldfogle DDS 《The Journal of prosthetic dentistry》1997,77(6):568-572
Statement of problem. Controversy surrounds the use of hydrofluoric acid to prepare precementation surfaces of indirect composites.Purpose. This study was conducted to compare effects of combining hydrofluoric or orthophosphoric acid with microetching as precementation treatments.Material and methods. Nine specimens of three composite materials were prepared to simulate heat-cured indirect restorations. The specimen surfaces were prepared with one of three treatments. Adhesive Bond II and Twinlook cements were used to bond a phosphoric acid-etched disk of P50 to the treated surface. Analysis of variance and Scheffé tests were used to assess the bond strength data. Scanning electron microscopy and microscopic analysis of the fractured and treated surfaces were also performed.Results. Bond strengths for all surface treatments did not significantly differ. Hybrids had a higher bond strength with etching than microfills, and mechanical roughening produced the greatest bond strengths with microfills. Microetching with orthophosphoric acid produced higher bond strengths than microetching with hydrofluoric acid on hybrids.Conclusions. Acid etching alone is not sufficient to produce effective bond strengths, and hydrofluoric acid treatments are detrimental to the resin composite. (J Prosthet Dent 1997;77:568-72.) 相似文献
59.
David J. Murray Robert B. Forbes Judith B. Dillman Larry T. Mahoney David L. Dull 《Journal canadien d'anesthésie》1989,36(3):295-300
In this study, two-dimensional and pulsed Doppler echocardiography were used to measure cardiovascular changes before and
after IV atropine in 31 infants and small children during halothane (n = 15) or isoflurane (n = 16) anaesthesia. Prior to
induction of anaesthesia heart rate (HR), mean blood pressure (MBP), and two0dimensional echocardiographic dimensions of the
left ventricle and pulmonary artery bloodflow velocity were measured by pulsed Doppler echocardiography. Cardiovascular measurements
were repeated while anaesthesia was maintained at 1.5 MAC halothane (n = 15) or isoflurane (n = 16). Atropine 0.02 mg·kg−1 IV was then administered and two minutes later, a third set of cardiovascular data was obtained. Heart rate decreased during
halothane anaesthesia but did not change significantly during isoflurane anaesthesia. Mean blood pressure, cardiac output
(CO) and stroke volume (SV) decreased similarly during 1.5 MAC halothane or isoflurane anaesthesia. Ejection fraction (EF)
decreased and left ventricular end-diastolic volume (LVEDV) increased significantly in bothgroups, but decreases in EF (32
± 5 percentvs18 ± 5 per cent) and increases in LVEDV (18 ± 7 per cent vs7 ± 5 per cent) were significantly greater during
halothane than during isoflurane anaesthesia. Following atropine, HR increased more in the patients maintained with halothane
(31 ± 6 per cent), than during isoflurane anaesthesia (18 ± 5 per cent). Atropine increased CO in both groups of patients,
but SV and EF remained unchanged. When compared with awake values, HR increased similarly and significantly (18 ± 4 per cent)
following atropine in both groups, and CO returned to control levels. Halothane decreased EF and increased LVEDV more than
isoflurane at 1.5 MAC end— expired anaesthetic levels. Atropine did not diminish the myocardial depression produced by halothane
or isoflurane. The increase in CO following atropine during halothane and isoflurane anaesthesia in infants and small children
is the result of increases in HR alone.
Nous avons utilisé un appareil à échocardiographie bi-dimensionnelle couplé à un Doppler pulsé chez des bébés et de jeunes
enfants pour évaluer l’impact hémodynamique de l’halothane (n = 15) et de l’isoflurane (n = 16) et la modification possible
de ces effets par l’atropine. Nous avons mesure la frequence cardiaque (FC), la pression artérielle moyenne (PAM), la dimension
de la cavité ventriculaire gauche (par écho bi-dimensionnelle) et la vélocité du flot sanguin pulmonaire (par Doppler) et
ce, en trois occasions soit avant l’induction, après l’instauration de 1.5 MAC d’halothane ou d’isoflurane et finalement,
deux minutes après l’injection IV de 0.02 mg·kg−1 d’atropine. On ne nota une baisse de la frequence cardiaque qu’avec l’halothane tandis que la PAM, le débit cardiaque (DC)
et le volume d’éjection (VE) diminuaient autant avec l’un ou l’autre anesthésique. La diminution de la fraction d’éjection
(FE) et l’augmentation du volume télédiastolique du ventricule gauche (VTDVG) significatives pour les deux groupes, étaienl
plus marqué avec l’halothane qu’avec l’isoflurane: FE 32 ± 5 pour cent vs18 ±5 pour cent; VTDVG 18 ± 7 pour cent vs 7 ± 5
pour cent. Avec l’atropine, la FC monta plus dans le groupe halothane (31 ± 6 pour cent) que dans le groupe isoflurane (18
± 5 pour cent), le DC augmentant dans les deux groupes, alors que le VE et la FE demeuraient inchangés. Comparée aux mesures
pré-induction, l’atropine amenait une hausse significative de la FC, semblable dans les deux groupes (18 ± 4 pour cent) et
restaurait le DC. Donc, chez les bebes et les jeunes enfants, a 1.5 MAC, l’halothane diminue la FE et augmente le VTDVG plus
que ne le fait l’isoflurane. L’atropine ne modifie pas la depression myocardique et elle ne restaure le DC que par une hausse
de la FC.
Supported by PHS Grant No. 8507300 from the College of Medicine, University of Iowa Hospital, Iowa City, IA. 相似文献
Supported by PHS Grant No. 8507300 from the College of Medicine, University of Iowa Hospital, Iowa City, IA. 相似文献
60.
Donald L. Phillips James L. Pirkle Virlyn W. Burse John T. Bernert Jr. L. Omar Henderson Larry L. Needham 《Archives of environmental contamination and toxicology》1989,18(4):495-500
Twenty healthy adult humans had serum samples drawn on four occasions within a 24-hr period: after a 12 hr overnight fast, 4–5 hr after a high fat breakfast, at midafternoon, and the next morning after another 12 hr fast. Nonfasting samples had 22% to 29% higher mean concentrations (p < 0.05) than did fasting samples for polychlorinated biphenyls (PCBs, 4.81 vs 3.74 ng/g serum wt), hexachlorobenzene (HCB, 0.163 vs 0.134 ng/g serum wt), andp,p-dichlorodiphenyldichloroethylene (p,p-DDE, 6.74 vs 5.37 ng/g serum wt) measured by electron capture gas liquid chromatography. Total serum lipids were estimated from measurements of total cholesterol, free cholesterol, triglycerides, and phospholipids and were 20% higher in nonfasting samples than in fasting samples (7.05 g/L vs 5.86 g/L). When PCBs, HCB, andp,p-DDE concentrations were corrected by total serum lipids, results from fasting and nonfasting samples were not statistically different. Because of the differences in these chlorinated hydrocarbon concentrations observed with different sample collection regimens, meaningful comparison of analytical results requires standardizing collection procedures or correcting by total serum lipid levels. 相似文献