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91.
To identify treatment factors that may affect the survival of children with inv(16)(p13.1q22), we compared the outcomes of 19 patients with this genetic feature treated at our institution during two treatment eras. Nine patients were treated during era 1 (1980 to 1987), and 10 were treated during era 2 (1988 to 1996). All entered complete remission (CR) with induction therapy. Eight of the nine children treated in era 1 died, seven of relapsed leukemia. In contrast, three of 10 patients treated during era 2 have died, all of non-disease-related causes. Event-free survival (EFS) estimates were significantly higher for patients treated during era 2 than for those treated during era 1 (P = 0.03); the 6-year estimates were 70 +/- 15% (s.e.) and 11 +/- 7%, respectively. Era 2 treatment protocols differed from those of era 1 in their use of higher doses of cytarabine and etoposide during induction and consolidation chemotherapy and in their use of 2-chlorodeoxyadenosine (2-CDA). These results suggest that dose intensification of cytarabine benefits children with AML and inv(16), as is the case in adults. They also suggest that dose intensification of etoposide and addition of 2-CDA may also offer an advantage. This study underscores the dependence of the prognostic impact of cytogenetic features on the efficacy of treatment.  相似文献   
92.
静息状态脑功能网络的研究及应用   总被引:1,自引:0,他引:1  
目的:对静息状态网络的研究方法、初步的研究成果等作以介绍,并结合静息状态网络在阿尔茨海默病早期预警中的应用,介绍静息状态脑网络的应用。资料来源:应用计算机检索PubMed1980-01/2006-12与静息状态网络相关的文献,检索词“restingstate,functional connectivity”,并限定文献语言种类为“English”;同时计算机检索万方数据库1995-01/2006-12有关方面的文献,检索词为“静息,功能连接,阿尔茨海默病”,并限定语言种类为中文。资料选择:对资料进行初审,选取包括静息状态的相关文献,开始查找原文。纳入标准:①有关静息状态脑网络和功能连接的研究。②有关阿尔茨海默病的研究。排除标准:重复研究。资料提炼:共收集到53篇有关静息状态网络方面的研究,排除23篇重复性研究,30篇符合要求。资料综合:近年来,研究者发现大脑处于无任务的静息状态时,仍然存在着某种功能活动。这些现象表明大脑在静息状态时可能存在有组织的网络。这有助于对人脑高级意识和某些认知疾病的研究,因此,有关这方面的工作越来越受到人们的重视。结论:对静息状态网络的本质和规律的研究还很有限,对这个网络所支持的精确的功能还有待于进一步研究。  相似文献   
93.
Context  Little is known about the incidence of secondary neoplasms after 15 to 20 years in children and adolescents who were treated for acute lymphoblastic leukemia. Objectives  To investigate the cumulative incidence of secondary neoplasms in pediatric patients treated for acute lymphoblastic leukemia over 30 years and to characterize late-occurring tumors. Design, Setting, and Patients  Retrospective study of 2169 patients with acute lymphoblastic leukemia treated between 1962 and 1998 at St Jude Children's Research Hospital, Memphis, Tenn, who achieved complete remission and had a median follow-up time of 18.7 years (range, 2.4-41.3 years). Main Outcome Measures  Cumulative incidences of secondary neoplasms in first remission and standard incidence ratios of observed rates compared with rates of cancer development in the general US population. Results  Secondary neoplasms developed as the first event in 123 patients and comprised 46 myeloid malignancies, 3 lymphomas, 14 basal cell carcinomas, 16 other carcinomas, 6 sarcomas, 16 meningiomas, and 22 other brain tumors. The cumulative incidence of secondary neoplasm was 4.17% (SE, 0.46%) at 15 years and increased substantially after 20 years, reaching 10.85% (SE, 1.27%) at 30 years. When meningiomas and basal cell carcinomas were excluded, the overall cumulative incidence was 3.99% (SE, 0.44%) at 15 years and 6.27% (SE, 0.83%) at 30 years, representing a 13.5-fold increase in overall risk compared with the general population. The cumulative incidence of each tumor type at 30 years was 2.19% (SE, 0.32%) for myeloid malignancy, 0.17% (SE, 0.10%) for lymphoma, 3.00% (SE, 0.59%) for brain tumor, 4.91% (SE, 1.04%) for carcinoma, and 0.57% (SE, 0.37%) for sarcoma. Conclusions  The cumulative incidence of secondary neoplasms increases steadily over 30 years after treatment of acute lymphoblastic leukemia. Although the majority of the late-occurring secondary neoplasms are low-grade tumors, the increase in incidence of more aggressive malignant neoplasms is significantly higher than expected in the general population. These results suggest that lifelong follow-up of acute lymphoblastic leukemia survivors is needed to ascertain the full impact of treatment and other leukemia-related factors on secondary neoplasm development.   相似文献   
94.
马蓝的化学成分研究   总被引:15,自引:0,他引:15  
Seven compounds have been isolated from the whole plant of Strobilanthes cusia (Nees) O. Ktze. Three of them are triterpenes (Ⅰ~Ⅲ), two are indole alkaloids (Ⅳ, Ⅴ), two are quinazolinone alkaloids (Ⅵ, Ⅶ). On the basis of spectral analysis and physicochemical properties, their structures were established as lupeol (Ⅰ), betulin (Ⅱ), lupenone (Ⅲ), indigo (Ⅳ), indirubin (Ⅴ), 4 (3H)-quinazolinone (Ⅵ), 2, 4 (1H, 3H)-quinazolinedione (Ⅶ). Ⅵ and Ⅶ were found from natural plant for the first time.The results of the pharmacological tests demonstrate that compound Ⅴ has anticancer activity and compound Ⅵ has hypotensive action. Compound Ⅶ can be quantitatively determined by HPLC, which may serve as a quality control standard for materia medica and its preparations. Compounds Ⅵ and Ⅶ have been confirmed by means of synthesis.  相似文献   
95.
The clinical significance of interleukin 2 receptor (IL2R) concentrations in serum was determined for 344 children with newly diagnosed acute lymphoblastic leukemia (ALL). Serum levels of IL2R in patients (267 to 80,000 U/mL, median 2,007 U/mL) were significantly higher than normal control values (170 to 738 U/mL, median 347 U/mL) (P less than .0001). Measurements in cases of T cell ALL were lower than in the non-T, non-B cases (P = .02). Among the 264 patients with non-T, non-B ALL, but not in those with T cell disease, higher serum IL2R levels (greater than 2,000 U/mL) were associated with a poorer treatment outcome (P = .04). In a multivariate analysis, serum IL2R level contributed independent prognostic information beyond that conveyed by leukocyte count, race, and age (P = .04). One explanation for these results is that soluble IL2R competes with normal lymphocyte- integrated IL2R for the ligand and thus could suppress host antitumor immunity.  相似文献   
96.
97.
The definition of remission in acute leukemia with immunologic techniques.   总被引:1,自引:0,他引:1  
In acute leukemia residual disease is usually monitored by morphology. The precision of this approach can be improved by several methods including the investigation of chromosomal abnormalities by conventional cytogenetics, flow karyotyping, in situ hybridization and polymerase chain reaction (PCR), and the analysis of immunoglobulin and T cell receptor genes by Southern blotting and PCR. Immunologic methods represent a reliable option for studying residual disease in approximately half of the patients with acute leukemia. This strategy is based on the observation that some marker combinations are expressed on leukemic blasts but are absent or rarely present in normal peripheral blood (PB), bone marrow (BM) or cerebrospinal fluid cells. In patients with T cell-acute lymphoblastic leukemia, even one cell simultaneously expressing terminal deoxynucleotidyl transferase and CD3, CD5 or CD1 amongst 10(5) PB or BM cells indicates residual disease. Some cases of B lineage and myeloid acute leukemias also exhibit phenotypes potentially useful for monitoring response to treatment. Such phenotypes are identified by double or triple color staining techniques using fluorescence microscopy or flow cytometry. Independent studies have demonstrated that detection of cells with leukemia-associated phenotypes in BM samples of patients in clinic and morphologic remission heralds the recurrence of leukemia. It is likely that a combination of techniques will be needed to monitor the majority of patients with acute leukemia. Advantages and disadvantages of individual methods should be determined in comparative preclinic investigations. These studies should yield sufficient information to initiate the testing of therapeutic strategies planned according to the data provided by use of modern sensitive techniques.  相似文献   
98.
The effects of smoking-related sensory cues on psychological stress   总被引:1,自引:0,他引:1  
Previous studies have shown that the sensory cues of cigarette smoking are important for smoking satisfaction and craving reduction. Sensory cues in the absence of pharmacological doses of nicotine have been found to be moderately satisfying and to reduce craving. The current study was conducted to determine if administration of the sensory cues of cigarette smoking with minimal nicotine would also provide relief from mild anxiety associated with anticipation of a difficult anagram test. This test has previously been shown to be sensitive to the anxiety relieving effects of cigarette smoking. Compared to the placebo control condition, the sensory condition caused a significant alleviation of the stress as measured by components of the Spielberger scale for anxiety. The addition of cigarette smoke containing 0.5 mg of nicotine to the sensory cues caused a slight though nonsignificant enhancement of the stress alleviation. These results demonstrate that sensory cues of smoking can provide similar effects as nicotine containing cigarettes with regard to stress alleviation. Previous studies had shown that sensory cues are important for the consumptive aspects of smoking (i.e., smoking satisfaction and craving reduction). The current study shows that sensory cues are important for other effects of smoking as well.  相似文献   
99.
In a review of 432 children with newly diagnosed acute lymphoblastic leukemia (ALL), we identified a new nonrandom translocation, tdic(9;12)(p1?1;p1?2), in the leukemic marrow cells of eight patients. Seven had hypodiploid karyotypes that lacked chromosomes 9 and 12 and contained a der(12), tdic(9;12); the eighth had a pseudodiploid karyotype with two normal 9 chromosomes, one normal 12 and the der(12), tdic(9;12). Abnormalities involving chromosomes other than 9 and 12 were noted in four of the eight patients. All cells with the tdic(9;12) expressed both the common ALL antigen and HLA-DR. Cytoplasmic immunoglobulin, a marker of pre-B ALL, was detected in one case with the tdic(9;12) but was absent in the other seven. Our results suggest that the tdic(9;12)(p1?1;p1?2) rearrangement is specifically associated with leukemic B cell precursors.  相似文献   
100.
Purpose

Sagittal malalignment is a risk factor for mechanical complications after surgery for adult spinal deformity (ASD). Spinal loads, modulated by sagittal alignment, may explain this relationship. The aims of this study were to investigate the relationships between: (1) postoperative changes in loads at the proximal segment and realignment, and (2) absolute postoperative loads and postoperative alignment measures.

Methods

A previously validated musculoskeletal model of the whole spine was applied to study a clinical sample of 205 patients with ASD. Based on clinical and radiographic data, pre-and postoperative patient-specific alignments were simulated to predict loads at the proximal segment adjacent to the spinal fusion.

Results

Weak-to-moderate associations were found between pre-to-postop changes in lumbar lordosis, LL (r =  − 0.23, r =  − 0.43; p < 0.001), global tilt, GT (r = 0.26, r = 0.38; p < 0.001) and the Global Alignment and Proportion score, GAP (r = 0.26, r = 0.37; p < 0.001), and changes in compressive and shear forces at the proximal segment. GAP score parameters, thoracic kyphosis measurements and the slope of upper instrumented vertebra were associated with changes in shear. In patients with T10-pelvis fusion, moderate-to-strong associations were found between postoperative sagittal alignment measures and compressive and shear loads, with GT showing the strongest correlations (r = 0.75, r = 0.73, p < 0.001).

Conclusions

Spinal loads were estimated for patient-specific full spinal alignment profiles in a large cohort of patients with ASD pre-and postoperatively. Loads on the proximal segments were greater in association with sagittal malalignment and malorientation of proximal vertebra. Future work should explore whether they provide a causative mechanism explaining the associated risk of proximal junction complications.

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