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81.
Antiangiogenic agents can induce a distinct MRI pattern in glioblastoma, characterized by a decrease in the contrast enhancement on T1‐weighted images and a simultaneous hyperintensity on T2‐weighted or fluid‐attenuated inversion recovery images.  相似文献   
82.
Sidney J. Blatt's unique contribution to the study of internal representations of parental figures is delineated, and empirical research dealing with interpersonal and intrapersonal aspects of maternal representations in middle childhood is reviewed. Children's representations of mother and father, as well as of an unknown parent, provide evidence of the interconnected effects of actual interpersonal experiences and intrapersonal factors. In addition, new findings related to cultural differences affecting children's maternal representations suggest a broader and more complex perspective for the definition of interpersonal experiences. Taken together, these studies suggest an understanding of an individual's internal world of representations as dialectical transactions between his or her circumstances and rules of organization of interpersonal knowledge, on one hand, and the actual interpersonal experiences and cultural beliefs, on the other. The importance of the study of continuity and change for the understanding of the effects of interpersonal and intrapersonal factors in children's construction of parental representations is underscored.  相似文献   
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84.
The development of platinum compounds and their possible combination   总被引:1,自引:0,他引:1  
Cisplatin plays a central role in cancer chemotherapy in spite of its toxicity. To circumvent this toxicity and to enhance its therapeutic index a lot of preclinical and clinical studies have been conducted and several thousand analogues have been synthesized. Much more analysis remains to be done, but nowadays, the absence of any definitive, biologically interpretable molecular predictor of activity is consistent with the idea that platinum compounds have multiple intracellular targets and that cells can have multiple mechanisms of resistance. This review analyses a part of these platinum compounds analyzed to date, their mechanism of action, resistance and the future trends in this sector.  相似文献   
85.
The Role of Chemotherapy in Recurrent Malignant Gliomas: An Overview   总被引:2,自引:0,他引:2  
First-line treatment of malignant gliomas invariably includes surgery when feasible, and often adjuvant radiotherapy with or without chemotherapy; at progression or recurrence, the only remaining possibility is chemotherapy. While the role of first-line treatment has been established by many randomized studies, second-line treatment is not as well defined. To analyze the difficulties encountered with cytotoxic drugs in relation to both the blood-brain barrier and drug resistance, we examined the results obtained by single-agent chemotherapy, drug combinations, and biological response modifiers. Our findings confirmed that the nitrosoureas are the most active substances at the time of recurrence; these agents give an approximately 30% global response rate, with about 20 weeks' survival. Although no comparative randomized studies regarding single- versus multiple-agent chemotherapy are available, the latter approach, including nitrosourea, can obtain an up to 40% rate of response, with survival ranging from 30 to 50 weeks. The role of interferons has been very controversial; individually, alpha- and beta-interferons seem to give a 20% response rate, with 20 weeks' survival. To date, they have never been used in combination with cytotoxic drugs, but they may prove synergistic without increasing toxicity. Studies addressing the quality of life of these patients are not available, and it is clear that we need more basic research in this field.  相似文献   
86.
BACKGROUND: As the U.S. population ages, there is an emerging need to characterize the "functional age" of older patients with cancer to tailor treatment decisions and stratify outcomes based on factors other than chronologic age. The goals of the current study were to develop a brief, but comprehensive, primarily self-administered cancer-specific geriatric assessment measure and to determine its feasibility as measured by 1) the percentage of patients able to complete the measure on their own, 2) the length of time to complete, and 3) patient satisfaction with the measure. METHODS: The geriatric and oncology literature was reviewed to choose validated measures of geriatric assessment across the following domains: functional status, comorbidity, cognition, psychological status, social functioning and support, and nutritional status. Criteria applied to geriatric assessment measurements included reliability, validity, brevity, and ability to self-administer. The measure was administered to patients with breast carcinoma, lung carcinoma, colorectal carcinoma, or lymphoma who were fluent in English and receiving chemotherapy at Memorial Sloan-Kettering Cancer Center (New York, NY) or the University of Chicago (Chicago, IL). RESULTS: The instrument was completed by 43 patients (mean age, 74 yrs; range, 65-87 yrs). The majority had AJCC Stage IV disease (68%). The mean time to completion of the assessment was 27 minutes (range, 8-45 mins). Most patients were able to complete the self-administered portion of the assessment without assistance (78%) and were satisfied with the questionnaire length (90%). There was no association noted between age (P = 0.56) or educational level (P = 0.99) and the ability to complete the assessment without assistance. CONCLUSIONS: In this cohort, this brief but comprehensive geriatric assessment could be completed by the majority of patients without assistance. Prospective trials of its generalizability, reliability, and validity are justified.  相似文献   
87.
PURPOSE: Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is indolent and often associated with Helicobacter pylori bacterial infection. H pylori-independent MALT develops either in the absence of the bacteria or persists after bacterial eradication. We have previously demonstrated long-term pathologic remission after involved-field radiotherapy therapy (IFRT). We determined molecular remission status by clonotypic polymerase chain reaction (PCR). PATIENTS AND METHODS: Twenty-four consecutive patients with stage I to IIE gastric MALT lymphoma who obtained a pathologic remission after IFRT alone were evaluated. All had at least two follow-up endoscopic gastroduodenal biopsies at Memorial Sloan-Kettering Cancer Center. IFRT median dose was 30 Gy (range, 28.5 to 43.5 Gy). Post-treatment biopsies were subjected to semi-nested clonotypic PCR. RESULTS: All patients obtained a complete response based on routine immunohistochemical pathologic analysis of random post-treatment gastric biopsies. Median follow-up from completion of IFRT was 63 months (range, 19 to 117 months). Event-free survival was 96%; 23 of 34 patients remained in clinical and pathologic complete remission. Baseline DNA extraction yielded 17 clone-specific primer pairs. At the first follow-up test, 14 of 17 pairs were PCR positive. Eight remained persistently positive; and one was persistently negative. Others were intermittently positive. CONCLUSION: Despite sustained biopsy-proven remissions for as long as 117 months after radiation, the vast majority of patients remain positive by clonotypic PCR. This suggests that the malignant clone is present but missing either an internal or external signal essential to the cancer phenotype. One possibility is that radiation eradicates the polyclonal H pylori-specific T cells eliminating critical local factors necessary for proliferation of the monoclonal B cells.  相似文献   
88.
The study of neurogenetic microdeletion syndromes provides an insight into the developmental psychopathology of psychiatric disorders. The aim of the study was to evaluate the prevalence of psychiatric disorders, especially obsessive-compulsive disorder (OCD), in patients with velocardiofacial syndrome (VCFS), a 22q11 microdeletion syndrome. Forty-three subjects with VCFS of mean age 18.3 +/- 10.6 years were comprehensively assessed using semi-structured psychiatric interview and the Yale-Brown obsessive compulsive scale (Y-BOCS). Best estimate diagnoses were made on the basis of information gathered from subjects, parents, teachers, and social workers. Fourteen VCFS subjects (32.6%) met the DSM-IV criteria for OCD. OCD had an early age of onset and generally responded to fluoxetine treatment. It was not related to mental retardation. The most common obsessive-compulsive symptoms were contamination, aggression, somatic worries, hoarding, repetitive questions, and cleaning. Sixteen of the 43 patients (37.2%) had attention-deficit/hyperactivity disorder (ADHD), and 7 (16.2%) had psychotic disorder. The results of our study suggest that there is a strong association between VCFS and early-onset OCD. This finding may be significant in the understanding of the underlying genetic basis of OCD.  相似文献   
89.
Effacement of podocyte foot processes occurs in many proteinuric nephropathies and is accompanied by rearrangement of the actin cytoskeleton. Here, we studied whether protein overload affects intracellular pathways, leading to cytoskeletal architecture changes and ultimately to podocyte dysfunction. Mouse podocytes bound and endocytosed both albumin and IgG via receptor-specific mechanisms. Protein overload caused redistribution of F-actin fibers instrumental to up-regulation of the prepro-endothelin (ET)-1 gene and production of the corresponding peptide. Increased DNA-binding activity for nuclear factor (NF)-kappaB and Ap-1 nuclear proteins was measured in nuclear extracts of podocytes exposed to excess proteins. Both Y27632, which inhibits Rho kinase-dependent stress fiber formation, and jasplakinolide, an F-actin stabilizer, decreased NF-kappaB and Ap-1 activity and reduced ET-1 expression. This suggested a role for the cytoskeleton, through activated Rho, in the regulation of the ET-1 peptide. Focal adhesion kinase (FAK), an integrin-associated nonreceptor tyrosine kinase, was phosphorylated by albumin treatment via Rho kinase-triggered actin reorganization. FAK activation led to NF-kappaB- and Ap-1-dependent ET-1 expression. These data suggest that reorganization of the actin cytoskeletal network in response to protein load is implicated in modulation of the ET-1 gene via Rho kinase-dependent FAK activation of NF-kappaB and Ap-1 in differentiated podocytes. Increased ET-1 generation might alter glomerular permselectivity and amplify the noxious effect of protein overload on dysfunctional podocytes.  相似文献   
90.
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