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Summary: Purpose: Quantitative MRI techniques provide an unparalleled opportunity to examine in vivo the relationship between the extent and laterality of hippocampal pathology and associated neuropsychological deficits. The purpose of this study was to examine the nature of the relationship between quantitative measures of hippocampal pathology and neuropsychological measures, using a multivariate approach. Methods: We examined the relationship between two MRI measures of hippocampal structure; hippocampal volumes (HCvol) and T2 relaxation times (HCT2), and memory performance, in 80 presurgical temporal lobe epilepsy patients. Results: As a group, patients with left hippocampal sclerosis (LHS) performed more poorly that those with right hippocampal sclerosis (RHS) on immediate and delayed prose recall. In the group as a whole, right hippocampal volume was significantly correlated with the delayed recall of a complex figure. None of the verbal memory test scores were significantly correlated with the right or left HCvol or HCT2 measures. However, stepwise multiple regression analyses indicated that up to a third of the variation in specific test scores could be explained by the quantitative MRI hippocampal measures in conjunction with chronological age, and age at onset of habitual epilepsy. Left hippocampal measures explained 24% of the variance in the story-recall tasks, while right hippocampal measures explained 18% of the variance in a design-learning task and 32% of the variance in a figure-recall task. Conclusions: Our results provide some support for the lateralised model of material specific memory deficits, but suggest that a number of demographic and epilepsy-related factors may interact with the extent and laterality of hippocampal pathology in shaping the nature of the associated neuropsychological deficit.  相似文献   
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Background: The Bullard laryngoscope is useful for the management of a variety of airway management scenarios. Without the aid of a video system, teaching laryngoscopy skills occurs with indirect feedback to the instructor. The purpose of this study was to determine if use of a video system would quicken the process of learning the Bullard laryngoscope or improve the performance (speed or success) of its use.

Methods: Thirty-six anesthesia providers with no previous Bullard laryngoscope experience were randomly divided into two groups: initial training (first 15 intubations) with looking directly through the eyepiece (n = 20), or with the display of the scope on a video monitor (n = 16). The subjects each then performed 15 Bullard intubations by looking directly through the eyepiece.

Results: There was not an overall significant difference in laryngoscopy or intubation times between the groups. When only the first 15 intubations were considered, the laryngoscopy time was shorter in the video group (26 +/- 24) than in the nonvideo group (32 +/- 34;P < 0.04). In the first 15 patients, there were fewer single attempts at intubation (67.9%vs. 80.3%;P < 0.002) and more failed intubations (17.2%vs. 6.0%;P < 0.0001) in the nonvideo group.  相似文献   

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We performed a literature search for all clinical studies reporting outcomes in patients with the acquired immunodeficiency syndrome (AIDS) receiving granulocyte-macrophage colony-stimulating factor (GM-CSF) for any indication. Safety outcomes included human immunodeficiency virus replication, immune status, and frequency of opportunistic infections and neoplasms. Data were synthesized qualitatively. We identified 22 studies (274 patients): 12 addressed AIDS neutropenia, 8 AIDS cancer therapy, and 2 opportunistic infections. Viral burden was assessed by serum p24Ag in 15 studies. Nine reported no change in levels, three net decreases, and three net increases. All studies showing net increases involved patients receiving GM-CSF without a concurrent antiretroviral. The CD4 counts were unchanged in 5 studies, increased in 3, and not reported in 14. The incidence of neoplasms or new opportunistic infections was low. The literature suggests no increased risk of viral replication or clinical deterioration in patients with AIDS who take GM-CSF concurrently with zidovudine.  相似文献   
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The viability and drug responses of cryopreserved adult Onchocerca have been examined in vitro. Male worms were cryopreserved in liquid nitrogen (-196 degrees C) using ethanediol as a cryoprotectant in a 2-step incubation procedure. After thawing, 85-90% of O. gutturosa males were normally motile. These motile worms were evaluated for viability using 4 measurements (long-term motility/survival in culture; [U-14C]adenine uptake and leakage; glucose utilization; MTT-formazan colorimetry) and were no different from unfrozen controls. Subsequent experiments demonstrated that the motility responses of cryopreserved worms exposed to the antifilarial drugs ivermectin, CGP 6140 and levamisole were virtually identical to unfrozen controls. Some success was also obtained with this technique in cryopreserving O. volvulus males, with 2 thawed specimens surviving in culture for 93 and 106 d respectively. Following collagenase isolation, female worms were cryopreserved in medium +10% serum without protectant at -79 degrees C. A batch of 8 female O. gutturosa were all motile when thawed 14 d later, with a mean survival time (based on 5 specimens) of 71 d (range 60-90). However, a batch of worms transferred from -79 degrees C to -196 degrees C were badly damaged when thawed. Female O. volvulus were cryopreserved at -79 degrees C in Guatemala and sent by air freight on solid CO2 to the UK. Most specimens were active when thawed. Survival of motile specimens ranged from 7 to 272 d in culture. It is concluded that these techniques are of practical value for the storage and transportation of adult Onchocerca.  相似文献   
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Summary Between 1955 and 1986, 25 children (aged 2 weeks to 15 years) were treated for intracranial ependymoma at M.D. Anderson Cancer Center. Nine patients had supratentorial primaries (5 high-grade, 4 low-grade), and 16 had infratentorial primaries (9 high-grade, 7 low-grade). Five patients had gross complete resection and 20 had incomplete resection. Seven patients received craniospinal irradiation (25–36 Gy to the neuroaxis, 45–55 Gy to tumor bed), 12 received local field irradiation (29–60 Gy, median 50 Gy). Five infants had adjuvant chemotherapy without radiotherapy, and 6 children had postradiotherapy adjuvant chemotherapy, and 12 patients had salvage chemotherapy with various agents and number of courses. Eight patients are alive, disease-free and without relapse from 1 year to 12 1/2 years from diagnosis (median 42 months). The primary failure pattern was local recurrence. The data suggest that 1) the long-term cure rate of children with ependymoma is suboptimal; 2) histologic grade may be of prognostic importance for supratentorial tumors; 3) prognosis appears worse for girls and infants under 3 years of age; 4) in well-staged patients routine spinal irradiation could be omitted; 5) the role of adjuvant chemotherapy is unclear. Address for offprints: Shiao Y. Woo, Department of Radiation Oncology, 6565 Fannin, M.S. DB1-37, Houston, Texas 77030, USA  相似文献   
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Platelet utilization in a university hospital   总被引:3,自引:0,他引:3  
Two hundred forty-three patients received 22,717 U of platelets in our hospital during a three-month period. Those with hematologic diseases accounted for 43% of the patients but used 86% of the platelets. Sixty-eight percent of the transfusions were given to prevent bleeding and 32% were given to treat active bleeding. Ninety-two percent of therapeutic transfusions but only 22% of prophylactic transfusions met guidelines established by the Transfusion Therapeutics Committee of the University of Minnesota Hospital and Clinics, Minneapolis. However, 78% of prophylactic platelet transfusions that did not meet the guidelines involved patients with at least one clinical factor that their physicians believed placed them at an increased risk of bleeding. Following this analysis, the guidelines were modified and applied prospectively to requests for platelets. This resulted in a 14% decrease in the number of platelet units used during the following year. We conclude that published recommendations for platelet transfusions do not reflect the complex nature of many patients' conditions and that the use of guidelines developed by the medical staff can alter the use of platelet transfusions.  相似文献   
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