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1.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma   总被引:9,自引:3,他引:6  
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study.  相似文献   
2.
Anestrous hamsters exhibit daily afternoon gonadotropin and progesterone surges, but little estrogen secretion. In the first experiment, short day anestrous females were transferred to long days to detect hormonal changes associated with recovery of cyclicity. Morning and afternoon blood samples were taken at increasing durations in long days. Females autopsied at their first vaginal estrus after transfer to long days differed from long day estrous controls only in their lower uterine weights. Some females at all durations exhibited signs of recovery, though they had not yet shown estrus. They did not display afternoon gonadotropin surges and had low circulating progesterone but high estradiol levels, stimulated uteri, and enhanced follicular development. Results of the second and third experiments provided evidence that the daily gonadotropin surges are not the cause per se of anestrus, and that changes in estrogen secretion are essential for the transition to and from anestrus. Phenobarbital blockade of the daily surges in anestrous females did not result in increased follicular growth and estrogen secretion. Furthermore, daily afternoon injections of gonadotropins it appears that the daily surges in anestrous hamsters simply reflect low estradiol levels. It is still not known what signal promotes rapid follicular maturation during the recovery from anestrus. Once initiated, however, this recovery appears to occur within a few days, with a rapid cascade of events. First, follicular development and estrogen secretion resume, and the daily LH surges cease. Then, progesterone levels decline, and an ovulatory surge of gonadotropins is triggered.  相似文献   
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Winkler  ML; Olsen  WL; Mills  TC; Kaufman  L 《Radiology》1987,165(1):203-207
Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study.  相似文献   
5.
ABSTRACT: Background: The addition of supplementary prenatal support may improve the health and well‐being of high‐risk women and families. The objective of this randomized controlled trial was to examine the impact of supplementary prenatal care on resource use among a community‐based population of pregnant women. Methods: Pregnant women from three urban maternity clinics were randomized (a) to current standard of physician care, (b) to current standard of care plus consultation with a nurse, or (c) to (b) plus consultation with a home visitor. Participants were 1,352 women who received 3 telephone interviews. The primary outcome was resource use (e.g., attended prenatal classes, used nutritional counseling). Results: Overall, those in the nurse intervention group were more likely to attend an “Early Bird” prenatal class and parenting classes, and to use nutrition counseling and agencies that assist with child care. Women provided with extra nursing and home visitation supports were more likely to use a written resource guide, nutrition counseling, and agencies that assist with child care. Among women at higher risk (e.g., language barriers, young maternal age, low income), the nurse intervention significantly increased use of early prenatal classes, whereas the nurse and home visitor intervention significantly increased use of the written resource guide and nutrition counseling. The intervention substantially increased the amount of information received on numerous pregnancy‐related topics but had little impact on resource use for mental health and poverty‐related needs. Among those with added support, resource use among low‐risk women was generally greater than among high‐risk women. Conclusions: Additional support provided by nurses, or nurses and home visitors, can successfully address informational needs and increase the likelihood that women will use existing community‐based resources. This finding was true even for high‐risk women, although this intervention did not reduce the difference in resource use between high‐ and low‐risk women. (BIRTH 33:3 September 2006)  相似文献   
6.
Tricho-dento-osseous syndrome (TDO), MIM# 190320, is transmitted as a highly penetrant autosomal dominant trait that is characterized by variable clinical expression. The principal clinical features include kinky/curly hair in infancy, enamel hypoplasia, taurodontism, as well as increased thickness and density of cranial bones. Possible genetic linkage has been reported for TDO with the ABO blood group locus, but the gene defect remains unknown. We have identified four multiplex families (n = 63, 39 affected, 24 unaffected) from North Carolina segregating TDO. We previously have excluded a major locus for TDO in the ABO region for these families. Utilizing a genome-wide search strategy, we obtained conclusive evidence for linkage of the TDO syndrome locus to markers on chromosome 17q21 (D17S791, Z max = 10.54, Theta = 0.00) with no indication of genetic heterogeneity. Multipoint analysis suggests the TDO locus is located in a 7 cM chromosomal segment flanked by D17S932 and D17S941. This finding represents the first step towards isolation and cloning of the TDO gene. Identification of this gene has important implications for understanding normal and abnormal craniofacial development of hair, teeth and bone.   相似文献   
7.
The Bethlem myopathy is a rare autosomal dominant proximal myopathy characterized by early childhood onset and joint contractures. Evidence for linkage and genetic heterogeneity has been established, with the majority of families linked to 21q22.3 and one large family linked to 2q37, implicating the three type VI collagen subunit genes, COL6A1 (chromosome 21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes. Mutations of the invariant glycine residues in the triple-helical domain-coding region of COL6A1 and COL6A2 have been reported previously in the chromosome 21-linked families. We report here the identification of a G-->A mutation in the N-terminal globular domain-coding region of COL6A3 in a large American pedigree (19 affected, 12 unaffected), leading to the substitution of glycine by glutamic acid in the N2 motif, which is homologous to the type A domains of the von Willebrand factor. This mutation segregated to all affected family members, to no unaffected family members, and was not identified in 338 unrelated Caucasian control chromosomes. Thus mutations in either the triple-helical domain or the globular domain of type VI collagen appear to cause Bethlem myopathy.   相似文献   
8.
Delayed graft function (DGF) after kidney transplantation is associated with an increased risk of graft failure. We studied the histologic findings among adult kidney transplant recipients transplanted between January 2000 and June 2015 who had DGF and had a kidney biopsy within 14 days of transplant. Death censored graft failure (DCGF) and death at 1 and 3 years after transplant were examined. A total of 269 transplant recipients fulfilled our selection criteria, of which 152 (56.51%) had acute tubular necrosis (ATN), 44 (16.4%) had acute rejection (AR), mainly T-cell mediated rejection (n = 31), 35 (13%) had ATN with AR (mainly T-cell mediated rejection, n = 26), and 38 (14.1%) had other pathology. Compared with those with ATN alone, kidney transplant recipients with AR alone had a significantly higher risk of DCGF at 1 year post transplant (adjusted hazard ratio = 3.70; 95% confidence interval 1.5-9.5; P = .006). Those with AR alone had an increased risk of DCGF at 3 years post transplant (hazard ratio = 3.10; 95% confidence interval 1.3-8.5; P = .01) in crude analyses. There was no association between DGF etiology and mortality. Early renal biopsy can be used to distinguish AR, which has protocolized treatments, from other etiologies. This could potentially alter allograft survival within 1 year of transplant complicated by DGF.  相似文献   
9.
0 引言为了克服离子选择电极(ISE)法的微量电位信号极易受环境温度变化及电子噪声的干扰问题,该仪器采用了参考电极,把参考电极与其测定电极装在同一测量室内,保持其相同的物理环境,使干扰源对所有电极的影响相同. 以内参液作为参考电极的测量对象,测得一个参考电极电位值,再测样品的电极电位值,二者相抵就消除了所叠加的干扰信号.  相似文献   
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