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1.
J E Richards A H Parmelee L Beckwith 《Electroencephalography and clinical neurophysiology》1986,64(1):1-11
Power spectral and discriminant analysis techniques were used to compare EEG records obtained at term and at 3 months past term from 5 groups of varying risk and developmental outcome. The groups were: healthy full-terms; healthy pre-terms with normal outcomes; sick pre-terms with normal outcomes; sick pre-terms with delayed development; sick pre-terms with later neurological problems. The EEG samples recorded at term were identified as belonging to the correct subject group at 52-70% accuracy, 20% being chance for 5 groups. The accuracy varied with the 4 classes of EEG patterns used. The individual subjects were also classified into their correct groups with few exceptions. Similar success was obtained with EEG samples selected from recording at 3 months past term. The predominant power spectral discriminating features were changes in intra- and inter-hemispheric coherence, and increased power, particularly in the middle and higher frequency range. Thus, computer analyses of EEG samples, using features not readily identified visually, differentiated risk from non-risk infants and also differentiated infants with substantial neonatal medical complications who have good or poor developmental outcomes. 相似文献
2.
3.
Douglas A. Weeks Richelle L. Malott Craig W. Zuppan Boleslaw H. Liwnicz J. Bruce Beckwith 《Ultrastructural pathology》1994,18(1):23-28
The rhabdoid tumor (RT) was first described as an aggressive neoplasm of unknown histogenesis affecting the kidneys of infants and young children, but has since been reported in all ages and in many other primary sites, including the central nervous system. It has been shown, however, that the histologic and cytologic features of RT can be mimicked by many other tumors of known histogenesis. For this and other reasons it remains controversial whether cases of putative extrarenal RT represent the same histogenetic entity as RT of the kidney (RTK), another entity or entities, or merely a diverse collection of unrelated tumors sharing a common morphologic phenotype. The present paper describes a lethal primary cerebral tumor in a 26-month-old Hispanic boy that was composed predominantly of cells exhibiting the “classic” rhabdoid phenotype by light microscopy. lmmunocytochemical and ultrastructural studies disclosed features of primitive neuroglial differentiation not seen in RTK. The findings in this case, as well as evidence from other studies, would seem to support the notion that primary RT of the brain may in fact constitute a morphologic and clinicopathologic entity. However, hat entity likely represents a distinctive type of neuroglial neoplasm, more closely related t o other primitive brain tumors than t o RTK. 相似文献
4.
Cell division in Escherichia coli requires the recruitment of at least 10 essential proteins to the bacterial midcell. Recruitment of these proteins follows a largely linear dependency pathway in which depletion of one cell division protein leads to the absence from the division site of "downstream" proteins in the pathway. Analysis of events that underlie this pathway is complicated by the fact that a protein's ability to recruit "downstream" proteins is dependent on its own recruitment by "upstream" proteins. Hence, one cannot separate the individual contributions of various upstream proteins to any specific recruitment step. Here we present a method--premature targeting--for bypassing the normal localization requirements of a cell division protein and apply it to FtsQ, a protein recruited midway through the pathway. We fused FtsQ to the FtsZ-binding protein ZapA such that FtsQ was targeted to FtsZ rings independently of proteins FtsA and FtsK, which are normally required for FtsQ localization. Analysis of the resulting ZapA-FtsQ fusion suggests that FtsQ associates with a large complex of cell division proteins and that premature targeting of FtsQ can restore localization of this complex under conditions in which neither FtsQ nor the associated proteins would normally be localized. 相似文献
5.
Isolation of Corynebacterium aquaticum from spinal fluid of an infant with meningitis. 总被引:4,自引:1,他引:4
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A 4-week-old female was hospitalized because of vomiting, irritability, and nuchal rigidity. A spinal fluid culture yielded Corynebacterium aquaticum. The diagnosis of C. aquaticum meningitis in this infant was supported by the following cerebrospinal fluid findings: Gram stain, elevated protein, hypoglycorrhachia, positive C-reactive protein, and polymorphonuclear leukocytosis. Antigen studies for common bacterial causes of meningitis were negative. C. aquaticum is a rare cause of human disease and may be initially confused with Listeria monocytogenes, which is a more common gram-positive, motile rod associated with meningitis in infants. 相似文献
6.
Helicobacter hepaticus causes disease in the liver and lower intestinal tract of mice. It is strongly urease positive, although it does not live in an acidic environment. The H. hepaticus urease gene cluster was expressed in Escherichia coli with and without coexpression of the Helicobacter pylori nickel transporter NixA. As for H. pylori, it was difficult to obtain enzymatic activity from recombinant H. hepaticus urease; special conditions including NiCl2 supplementation were required. The H. hepaticus urease cluster contains a homolog of each gene in the H. pylori urease cluster, including the urea transporter gene ureI. Downstream genes were homologs of the nik nickel transport operon of E. coli. Nongastric H. hepaticus produces urease similar to that of H. pylori. 相似文献
7.
The bacterial membrane protein DsbD transfers electrons across the cytoplasmic membrane to reduce protein disulfide bonds in extracytoplasmic proteins. Its substrates include protein disulfide isomerases and a protein involved in cytochrome c assembly. Two membrane-embedded cysteines in DsbD alternate between the disulfide-bonded (oxidized) and reduced states in this process. 相似文献
8.
Relapse-associated variables in stage I favorable histology Wilms' tumor. A report of the National Wilms' Tumor Study 总被引:2,自引:0,他引:2
All 24 cases of confirmed and evaluable Stage I favorable histology (FH) Wilms' tumor (WT) relapsing to date on the Third National Wilms' Tumor Study (NWTS-3) were compared with 48 matched control subjects who had not relapsed for at least 2 years after diagnosis. Fifteen of the clinical and pathological variables studied, including patient age and tumor size, had no significant relationship to the outcome of this study. Four histologic features, all related to the degree of tumor extension within the "tumor-kidney unit" proved to be significantly associated with relapse. These were (1) invasion of the tumor capsule, (2) presence of an "inflammatory pseudocapsule," (3) renal sinus invasion, and (4) tumor in intrarenal vessels. One or more of these features was present in 100% of relapsed cases (excluding one for which two variables were unevaluable), but occurred in only 46% of controls (P less than 0.0002). Therefore, no relapses occurred in the NWTS-3 when all four variables were negative. This result was confirmed by a review of all Stage I cases in the NWTS-1 who had relapsed and who were treated by single-agent chemotherapy. Again, no relapses occurred when all four factors were negative. These results demonstrate the feasibility of "microsubstaging" and could serve as a basis for future refinements of therapy for Stage I favorable histology Wilms' tumor. 相似文献
9.
Histopathology and prognosis of Wilms tumors: results from the First National Wilms' Tumor Study. 总被引:13,自引:0,他引:13
Detailed histological analysis of 427 cases entered on the first National Wilms' Tumor Study revealed that lesions with foci of marked cytological atypism (anaplasia), and those composed predominantly of sarcomatous stroma, were associated with unfavorable outcome. Twenty-five patients had anaplasia, and 24 had sarcomatous lesions of which a total of 28 (57.1%) died of tumor. Three hundred and seventy-eight patients had tumors which showed neither of these features, and only 26 (6.9%) died of tumor. Seven of ten deaths due to tumor in patients diagnosed before two years of age were associated with sarcomatous lesions. Three sarcomatous patterns were recognized, of which one, designated "clear cell" sarcoma, had a predilection for bony metastases. Using criteria defined and illustrated in this paper it is possible to identify in advance those patients likely to do poorly using current therapeutic approaches. 相似文献
10.
Nita L Seibel Sierra Li Norman E Breslow J Bruce Beckwith Daniel M Green Gerald M Haase Michael L Ritchey Patrick R M Thomas Paul E Grundy Jerry Z Finklestein Tae Kim Stephen J Shochat Panayotis P Kelalis Giulio J D'Angio 《Journal of clinical oncology》2004,22(3):468-473
PURPOSE: To evaluate the effect of conventional and standard (ST) versus pulse-intensive (PI) chemotherapy and short-duration versus long-duration chemotherapy on relapse-free survival (RFS) and overall survival rates of patients with clear-cell sarcoma of the kidney (CCSK) entered onto the National Wilms' Tumor Study (NWTS)-4. PATIENTS AND METHODS: The 5-year and 8-year RFS rates were determined for patients with CCSK treated on the NWTS-4. After August 6, 1986, 40 previously untreated children younger than 16 years with CCSK were randomly assigned, after the completion of 6 months of chemotherapy, to discontinue (short) or continue 9 additional months (long) of treatment with chemotherapy regimens that included vincristine and either divided-dose (ST) courses (5 days) or single-dose (PI) treatment with dactinomycin and divided-dose (ST) courses (3 days) or single-dose (PI) treatment with doxorubicin. RESULTS: For patients with CCSK, the 5- and 8-year RFS rates were 65.2% and 60.6%, respectively, for patients randomly assigned to the short chemotherapy and 87.8% (both 5- and 8-year RFS) for patients randomly assigned to the long chemotherapy (P =.08). The overall survival rates for patients at 5 and 8 years were 95.5% and 85.9%, respectively, for the short chemotherapy and 87.5% (both 5- and 8-year overall survival) for the long chemotherapy (P =.99). In NWTS-4, the overall survival rates for patients with CCSK improved from NWTS-3 (83% v 66.9% at 8 years, respectively; P <.01). CONCLUSION: CCSK patients exhibit an improved RFS from a longer course of therapy when using vincristine, doxorubicin, and dactinomycin, but their long-term survival is unchanged compared with patients receiving 6 months of therapy. The overall survival rates for patients with CCSK have improved from NWTS-3. 相似文献