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1.
Changing attentional demands in left hemispatial neglect.   总被引:1,自引:0,他引:1  
Seven variations of a letter cancellation test were used to examine how varying attentional demands affect hemispatial neglect in patients with right hemisphere lesions. While the 14 targets always remained in the same location, the number of distractors (zero, nine, 28, or 82) as well as their complexity (one letter or nine different letters) were varied. The percentage of targets canceled in the left hemispace was linearly related to the number of distractors. There were no differences between the complexity conditions. In a second study, the same 14 targets were presented but the distractors (zero, 14, or 41) were all placed on the right. Increasing the number of distractors on the right increased neglect on both sides of the space. Taken together, these results suggest that, while the limited attentional resources of the left hemisphere are biased toward the right hemispace, the absence of contralateral attentional demands allows these resources to be directed ipsilaterally.  相似文献   
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BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most prevalent fatal cancers in the world. Despite advances in early diagnosis and improvements in surgical techniques, the survival of patients with HCC even after resection is poor because of the high incidence of recurrences. Therefore, the identification of prognostic factors may be helpful in the development of new treatment protocols. AIMS: To investigate HER-2/neu status in HCC by immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH), and to explore the possibility of using trastuzumab in the treatment of HCC. METH ODS: Eight hundred and sixty eight surgical samples from patients with primary HCC were examined for their HER-2/neu status. IHC for HER-2/neu was performed with the HercepTest kit; FISH analysis was performed with the PathVysion HER-2 DNA probe kit. The correlations between HER-2/neu overexpression and clinicopathological characteristics were analysed statistically. RESULTS: HER-2/neu overexpression was detected in 21 (2.42%) of the 868 primary HCCs. Only one specimen showed HER-2/neu gene amplification by FISH. No significant associations were found between HER-2/neu overexpression and the clinicopathological parameters. CONCLUSIONS: There is a low frequency of HER-2/neu overexpression/amplification in HCC. There appears to be no role for HER-2/neu as a prognostic marker and no benefit of anti-HER-2/neu trastuzumab treatment in patients with HCC.  相似文献   
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The Childrens Cancer Study Group has assessed serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), and pubertal development in 97 long-term female survivors of childhood acute lymphoblastic leukemia (ALL). All patients received identical induction and maintenance therapy with either 18 or 24 Gy of radiation therapy (RT) to one of the following fields: cranial, craniospinal, or craniospinal plus 12 Gy abdominal RT including the ovaries. Thirty-six percent (35 patients) were found to have above normal levels of FSH and/or LH. The percentages of elevated values for RT fields were 93% for craniospinal plus abdominal RT, 49% for craniospinal RT, and 9% for cranial RT (P less than .001). A dose-response relationship was observed between 18 Gy and 24 Gy in females receiving only craniospinal RT (P = .01). Craniospinal plus abdominal RT and abnormal FSH/LH levels were significantly associated with lack of pubertal development and delayed onset of menses. Duration of maintenance chemotherapy was not associated with abnormal gonadotropin levels or the development of secondary sexual characteristics. Additional follow-up of this cohort is needed to establish the ultimate pubertal development and fertility of these patients.  相似文献   
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To determine the appropriate role of surgical intervention in non-Hodgkin's lymphoma primary to the abdomen, we analyzed the effect of multiple prognostic determinants on event-free survival for patients entered into the CCG-551 study. Eighty-four patients were identified with abdominal lymphoma and of these adequate data for analysis was available on 68 (81%). Variables of interest included: extent of disease at diagnosis, completeness of resection, use of bowel resection, radiation to the primary site, and sex/age/race. The median age on study was 8 years; 79% of patients were white and 85% were male. Thirty-three patients (49%) presented with localized disease. Laparotomy was performed in 67 children (99%) with complete gross resection in 28 (42%). Of the 10 reported surgical complications, 8 occurred in those with extensive disease who were incompletely resected. Radiation to the primary site was given in 60% of patients with median dose of 2,000 cGy. Analysis was performed both for the overall group and for the subgroup receiving optimal chemotherapy for histopathology. Variables with significant predictive effect on event-free survival in univariate analysis included extent of disease (P less than or equal to .001), complete resection (P less than or equal to .002), and use of bowel resection (P less than or equal to .004). However, in multivariate analysis, only extent of disease was an independent predictor of outcome. The data support a role for complete operative excision of localized lymphomas especially when accomplished with bowel resection. Aggressive attempts at debulking extensive retroperitoneal or mesenteric lymphomas are contraindicated.  相似文献   
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P A Nathan  R C Keniston  L D Myers  K D Meadows 《JAMA》1992,268(6):787; author reply 787-787; author reply 780
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中西医结合医院单病种的质量管理及其作用   总被引:1,自引:0,他引:1  
针对中西医结合医院单病种质量评定没有现成的、规范的标准的现状,就中西医结合单病种的质量管理方法及其在中西医结合医院建设中的作用进行了论述。  相似文献   
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