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81.
Cytogenetic and histologic correlations in malignant lymphoma   总被引:9,自引:0,他引:9  
Although a number of studies have indicated correlations between histologic subtypes of tumors and certain nonrandom chromosome changes, cytogenetic studies of lymphoma are in an early stage compared to those of leukemia. No comprehensive analysis of available data has so far been attempted in the literature either. Here we present an analysis of chromosome changes and their correlation with subtypes of lymphoma studied by conventional histology and cell surface markers, as observed in two sets of data: a group of 65 karyotypically abnormal tumors sequentially ascertained and studied by us during the period January 1, 1984 to April 30, 1985, and a larger data set derived by combining our data with those from two published series from the University of Minnesota that are comparable to our data. These combined data, which comprise the largest data set on the cytogenetics of lymphomas assembled so far, enabled a comprehensive analysis of correlation between chromosome change and tumor histology and the patterns of chromosome instability in these tumors. We found several significant associations, some previously described and others now recognized, between nonrandom chromosome gains, breaks, translocations, and deletions and histologic subtypes of tumors that characterize lymphomas. The data indicate that finding of chromosome breaks at certain sites (eg, 8q24, 14q32, 18q21) is of diagnostic value in dealing with cases of unusual lymphoma. Furthermore, nonrandom chromosome breakage exhibited three distinct patterns that reflected three levels of etiologically relevant genetic change.  相似文献   
82.
Hemorrhagic tumor necrosis is an inflammatory event that leads to selective destruction of malignant tissues, with both potentially toxic and beneficial consequences. A pilot clinical trial was undertaken combining tumor necrosis factor-alpha (TNF-alpha) with the monoclonal antibody R24 (MoAb R24) against GD3 ganglioside in patients with metastatic melanoma. Patients received MoAb R24 to recruit leukocytes to the tumor followed by low doses of recombinant TNF-alpha to activate leukocytes. Eight patients were treated and seven patients had mild toxicity. One patient with extensive metastatic melanoma developed tumor lysis syndrome within hours after treatment with almost complete necrosis of bulky tumors in multiple visceral sites. To our knowledge, this is the first documented case of hemorrhagic tumor necrosis in a patient with metastatic cancer in multiple visceral sites.  相似文献   
83.
A 21 month old infant was found to have an intrapericardial haematic cyst at operation. This rare entity may be explained by a pouch-like dilatation of an atretic left superior vena cava.  相似文献   
84.

Clustering Latinos under a single group in Alzheimer Disease (AD) research, neglects, among other things cultural and environmental differences. To address this, we examine knowledge and attitudes about AD among two Latino groups. We held 5 focus groups and 2 interviews all in Spanish with Mexicans and Puerto Ricans between 40 and 60 years old living in the Grand Rapids area in Michigan. Using content analysis of the discussions, we identified themes related to knowledge, attitudes and concerns about AD and caregiving. A total of 20 Mexicans and 9 Puerto Ricans participated. Improving knowledge and awareness, barriers and home-based family care were important themes in both Latino groups. Puerto Rican groups raised more concerns about the disease, whereas lack of knowledge was a key theme among Mexican participants. The exploratory study is a first step in promoting research that is attentive to the commonalities and differences of Latino groups and in continuing efforts to enhance health literacy among these groups.

  相似文献   
85.
Age-related reference intervals (RIs) of aortic pulse wave velocity (Ao-PWV) obtained from a large healthy population are lacking in South America. The aims of this study were to determine Ao-PWV RIs in a cohort of healthy children and adolescents from Argentina and to generate year-to-year percentile curves.

Ao-PWV was measured in 1000 healthy subjects non-exposed to traditional cardiovascular risk factors (Age: 10–22 y. o., 56% males). First, we evaluated if RIs for males and females were necessaries (correlation and covariate analysis). Second, mean (M) and standard deviation (SD) age-related equations were obtained for cf-PWV, using parametric regression methods based on fractional polynomials. Third, age-specific (year to year) percentiles curves (for all, males and females children and adolescents) were generated using the standard normal distribution. They were, age-specific 1st, 2.5th, 5th, 10th, 25th, 50th, 75th, 90th, 95th, 97.5th and 99th percentile curves and values.

After covariate analysis (i.e., adjusting by age, jugulum-symphysis distance, body weight and height), specific RIs for males and females of children and adolescents were evidenced as necessaries. The equations were

For all subjects:

Ao-PWV_Mean = 4.98 + 12.86x10?5 Age3.

Ao-PWV_SD = 0.47 + 21.00x10?6Age3.

For girls:

Ao-PWV_Mean = 5.07 + 10.23x10?5Age3.

Ao-PWV_SD = 0.50 + 10.00x10?6Age3.

For boys:

Ao-PWV_Mean = 4.87 + 15.81x10?5Age3.

Ao-PWV_SD = 0.46 + 22.34x10?6Age3.

Our study provides the largest database to-date concerning Ao-PWV in healthy children and adolescents in Argentina. Age-related equations (M and SD values) for Ao-PWV are reported by the first time. Specific RIs and percentiles of Ao-PWV are now available according to age and sex for an Argentinian population.  相似文献   

86.
Rick  ME; Krizek  DM 《Blood》1986,67(6):1649-1654
Factor VIII coagulant protein (VIII:C) functions as a critical cofactor with factor IXa, calcium ions, and phospholipid during the activation of factor X. In the course of this reaction, the activity of VIII:C is first increased and then is destroyed by one or more serine proteases that are part of the coagulation sequence. In this study, we have investigated the influence of platelets on the inactivation of VIII:C by plasmin. Platelets were separated from plasma proteins in the presence of granule release inhibitors and were incubated with plasmin and isolated VIII:C or the complex of purified VIII:C/von Willebrand factor (vWF); VIII:C activity and antigen levels were assessed over time. In the presence of platelets, the isolated VIII:C showed an initial increase in VIII:C activity that was not present when platelets were absent, and the VIII:C/vWF showed an increase in VIII:C activity over that seen when platelets were absent. In addition, platelets stabilized VIII:C activity over a one-hour time course when compared with buffer. The VIII:C antigen did not increase and decreased slowly whether platelets were present or absent. Preincubating the platelets with ristocetin, collagen, or plasmin did not alter the results, and experiments using platelets from a patient with severe von Willebrand's disease also showed a pattern similar to that seen with normal platelets. Experiments using fixed platelets or phospholipid vesicles showed that they did not support the activation reaction or delay the inactivation reaction. These studies demonstrate that platelets modulate the activation and inactivation of VIII:C by plasmin, apparently by a mechanism that is independent of the platelet release reaction.  相似文献   
87.
BACKGROUND: A new prevalence of pain quality indicator based on the Minimum Data Set (MDS) has been developed for the purpose of providing nursing home (NH) consumers with information that would allow them to compare the quality of pain care between facilities. The purpose of this study was to compare pain-related care processes between NHs that scored in the lower 25th percentile (low pain prevalence) or upper 75th percentile (high pain prevalence) based on this indicator. METHODS: Care processes related to pain assessment, documentation, and treatment were independently evaluated using standardized resident interview and medical record review protocols for 255 residents in 16 NHs that reported MDS pain prevalence of less than 15% (8 NHs in lower 25th percentile) or greater than 30% (8 NHs in upper 75th percentile). RESULTS: A significantly greater proportion of participants in the high pain prevalence NHs reported symptoms indicative of chronic pain during interview. The standardized pain interview revealed a significantly higher prevalence of pain among participants in the lowest quartile NH group compared to the MDS pain prevalence quality indicator, but the pain prevalence according to both MDS and interview were comparable in the higher quartile NHs. Medical record review showed that a significantly greater proportion of participants in upper quartile NHs had pain assessments documented by licensed nurses and physicians, received pain medication, and had documentation of treatment response. CONCLUSIONS: An MDS pain quality indicator accurately discriminates prevalence of pain between facilities. However, interpretation of the pain indicator requires caution. Rather than reflecting poor quality, a high prevalence of pain according to the MDS was associated with better pain assessment and treatment care processes.  相似文献   
88.
89.
The number of infused cells is a very important factor in cord blood transplant (CBT) engraftment. Prior ex vivo expansion of aliquots of transplanted cord blood (CB) units is being investigated as a procedure to increase engraftment potential, but results are difficult to evaluate due to a lack of markers for assessing the contribution of expanded cells. We transplanted five patients, infusing the best available CB unit and cells from a second donor simultaneously. In two patients, these cells were obtained from another frozen CB unit by CD34(+)positive selection and culture expansion; the other three patients received uncultured highly purified haploidentical CD34(+) cells. The first two patients had DNA from the culture expanded CB cells detected only for a few days around day +11 when the absolute neutrophil count (ANC) was >200/microl; thereafter and when the ANC was <500/microl, only donor DNA from the uncultured CB was detected. For the other three patients, DNA analysis showed early and transient granulocyte engraftment of haploidentical cells, progressively replaced by the CB-derived granulocytes. We concluded that: (1) simultaneous infusion of lymphocyte-depleted HLA highly mismatched haematopoietic progenitor cells has not produced unfavourable effects for CBT; (2) the double transplant model is suitable for evaluating the engraftment potential of ex vivocultured CB cells in the clinical setting; (3) the culture conditions used did not result in early recovery of ANC; and (4) co-transplantation of purified uncultured HLA haploidentical CD34(+) cells may reduce the time of neutropenia following CBT.  相似文献   
90.
A 5.5-week-old infant with tricuspid atresia presented with severe hypoxemia not responding to the placement of a central shunt (4 mm polytetrafluorethylene). The infant was taken to the catheterization laboratory, where an AVE stent was successfully implanted in a severe postoperative stenosis, at the pulmonary end of the anastomosis. The oxygen saturation improved significantly, however, the infant died due to renal failure. The post-mortem anatomical findings are shown.  相似文献   
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