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Mark G. Burnett, Seema S. Sonnad and Sherman C. Stein

of dementia, gait dysfunction, and urinary incontinence in the context of enlarged ventricles and a normal CSF opening pressure and no apparent cause. Note, however, that the presence of these clinical factors has a positive predictive value of only 65% and a negative predictive value of 82%, leading many to propose tests that would improve sensitivity and specificity in diagnosing NPH. 87 Several diagnostic procedures have been proposed as screening tests for NPH. Isotope cisternography and clearance studies have been largely discredited. 78 , 86 , 88 More

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Robert A. Hirschl, Jeff Wilson, Brandon Miller, Sergio Bergese and E. Antonio Chiocca

prevalence, specificity, and sensitivity were calculated by using the Vassar calculator program ( ). Results Categorization of Cases After each comparison between the last iMR imaging study and the 1.5-T postoperative MR imaging study, the 74 cases were placed into 1 of 4 categories: Category A This “true negative” category included those cases where the 0.12-T iMR images and postoperative standard 1.5-T MR images were concordant with respect to the absence of residual tumor ( Fig. 1 ); 46% of the cases studied

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David W. Kimmel, Joan R. Shapiro and William R. Shapiro

M alignant gliomas account for 40% to 50% of the roughly 15,000 primary brain tumors diagnosed each year in this country. Despite aggressive therapy, median survival time is approximately only 1 year. The initial controlled studies on the use of nitrosoureas as adjuvant therapy demonstrated a modest but significant increase in long-term (18-month) survivors. Clinical resistance to chemotherapy has been a major problem. 27, 93 In an attempt to better understand drug resistance, investigators have developed in vitro assays to quantitate drug sensitivity in

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Phillip E. Vinall, Michael S. Kramer, Lynn A. Heinel and Robert H. Rosenwasser

artery sensitivity to touch during catheterization in the rats acclimated to 400 and 700 hours relative to those acclimated to 1600 and 1900 hours. The initial SAP was also lower during the early morning periods relative to the late afternoon. The turnover of norepinephrine in the rat's heart is significantly higher in the dark than in the light period, indicating that sympathetic tone is higher during the dark, active period relative to the resting (light) period. 27 In nocturnally active rats, pineal angiotensin—converting enzyme exhibits a pronounced circadian

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Eric M. Thompson, Kate Wagner, Kassi Kronfeld and Nathan R. Selden

ventricular shunt patency. Consensus is lacking, however, on the definition of a “normal” shuntogram. Various criteria have been proposed: 1) ventricular radiotracer entry, 9 , 10 , 12 2) distal cavity runoff between 10 and 20 minutes, 12 , 13 and 3) runoff half-life of < 10 minutes. 6 Even details of performing the shuntography procedure vary among institutions. For example, some but not all require pumping the shunt reservoir as part of the shuntogram. 1 , 9 , 13 The main aim of this study was to determine the sensitivity, specificity, positive predictive valve (PPV

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Sensitivity of human glioma and brain cells to natural killer cell lysis

Effects of serum concentration, epidermal growth factor, and time in culture

Rene L. Myers, Ronald L. Whisler, Ralph E. Stephens, Craig A. Sponseller, Kimberly Livingston, Paul M. Spring and Allan J. Yates

P revious evidence suggests that sensitivity to natural killer (NK) cytolysis may relate to cellular differentiation and the growth of target cells. 2, 5, 22, 23 For example, rapidly growing (fetal and progenitor) cells are more sensitive to NK cytolysis than the more slowly proliferating fully differentiated cells. Results of studies in our laboratory, which examined growth curves and cell cycle parameters, showed that we could alter the growth patterns of two human glioma cell lines and one normal brain cell line using different culture conditions: namely

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Margarida Julià-Sapé, Dionisio Acosta, Carles Majós, Àngel Moreno-Torres, Pieter Wesseling, Juan José Acebes, John R. Griffiths and Carles Arús

example, some lymphomas or some metastases). However, neuroimaging classification (defined as the assignment of type and grade) of brain tumors is frequently reported to be unreliable, especially for certain lesions such as gliomas. 16 , 17 To improve neuroimaging classification or to introduce other types of noninvasive diagnostic criteria, we must evaluate the accuracy of current methods. We are aware of only one study 11 in the literature in which the authors have provided detailed performance measures for MR imaging, such as sensitivity and specificity, for the

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Uroš Kovačič, Fajko Bajrović and Janez Sketelj

sensitivity of the skin, was possible by suturing the distal stump of a transected nerve end to side to an uninjured donor nerve. We also examined the effect of the surgically created end-to-side nerve communication on axonal histomorphometry in the donor nerve and its nociceptive function. We decided to use the intact sural nerve as the donor nerve and the distal nerve stump of the transected peroneal nerve as the recipient nerve. The sural nerve seems to be very suitable for examination of sensory axon growth through the reconstructed end-to-side nerve communication and

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Noboru Toda, Takashi Ozaki and Tomio Ohta

platelet extract, normally contained in the blood, 9, 10, 14, 15, 21 and with adrenergic nerves innervating the vascular wall, 6, 8 since these substances and the adrenergic transmitter, norepinephrine, cause cerebral vasoconstriction, and their antagonists relieve experimentally-induced vasospasm. However, there is little information concerning the correlation between vasospasm or SAH and sensitivity of cerebral vessels to vasoactive substances. The present study was undertaken in an attempt to clarify changes in cerebrovascular sensitivity to serotonin

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Marc-Eric Halatsch, Sarah Löw, Kay Mursch, Thomas Hielscher, Ursula Schmidt, Andreas Unterberg, Vassilios I. Vougioukas and Friedrich Feuerhake

mutation, in combination with maintenance of wild-type PTEN 19 and low levels of PKB/Akt, 13 contribute to a molecular signature of a subgroup of GBM that is likely to respond to EGFR inhibition. However, any combination of these molecular alterations appears in-sufficient to confer obligate sensitivity to erlotinib. 23 By analyzing erlotinib-sensitive, somewhat responsive, and erlotinib-resistant GBM cell lines, our aim in the present study was to determine additional candidate genes for mediating sensitivity or resistance to erlotinib in human GBM cells