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421.
Breast Cancer Research and Treatment - Metastatic triple negative breast cancer (mTNBC) is associated with poor prognosis and limited treatment options. It is known to be high immunogenic, with a...  相似文献   
422.
An indirect immunoperoxidase technique employing specific monoclonal antibodies has been used to identify leucocyte subpopulations in cytocentrifuge smears of washed human ejaculate. Cells reacting with the pan antihuman leucocyte monoclonal antibody (HLe-1) were demonstrated in 63/67 specimens from subfertile patients with a mean count of 14.5 +/- 17.1 leucocytes per HPF (X 320). Cells with similar reactivity were observed in all specimens examined from 10 fertile men with a mean count of 41.6 +/- 26.3 leucocytes per HPF (X 320). Leu-T4+ cells (T-lymphocytes) were demonstrated in only 13/63 of the subfertile group with a mean count of 4.46 +/- 3.3 T-lymphocytes per HPF (X 320). Studies with the anti-leu 2a antibody revealed that these leu-4+ cells were mainly of the suppressor/cytotoxic phenotype. In contrast, no leu-4+ cells were detected in the control group. No leu-12+ cells (B-lymphocytes) were detected in any of the 80 specimens examined.  相似文献   
423.

Objective

To evaluate the accuracy of computed tomography angiography (CTA) in predicting arterial encasement by limb tumours, by comparing CTA with surgical findings (gold standard).

Methods

Preoperative CTA images of 55 arteries in 48 patients were assessed for arterial status: cross-sectional CTA images were scored as showing a fat plane between artery and tumour (score 0), slight contact between artery and tumour (score 1), partial arterial encasement (score 2) or total arterial encasement (score 3). Reformatted CTA images were assessed for arterial displacement, rigid wall, stenosis or occlusion. At surgery, arteries were classified as free or surgically encased; 45 arteries were free and 10 were surgically encased.

Results

Multivariate logistic regression identified the axial CTA score as a relevant predictor for arterial encasement and subsequent vascular intervention during surgery. All sites where CTA showed a fat plane between the tumour and the artery were classified as free at surgery (n?=?28/28). The sensitivity of total arterial encasement on CTA (score 3) was 90%, specificity 93%, accuracy 93% and positive likelihood ratio 13.5.

Conclusion

CTA evidence of total arterial encasement is a highly specific indication of arterial encasement. The presence of fat between the tumour and the artery on CTA rules out arterial involvement at surgery.  相似文献   
424.
To assess the influence of graft-versus-host disease (GVHD) on recurrent leukemia and survival after allogeneic marrow transplantation, we studied 1,202 patients with acute nonlymphocytic leukemia (ANL), acute lymphocytic leukemia (ALL), and chronic myelogenous leukemia (CML) given unmodified marrow grafts from HLA- identical siblings. Proportional hazards regression models using acute GVHD and chronic GVHD as time-dependent covariates demonstrated a significant association of GVHD with a decreased relative risk (RR, 0.33 to 0.42) of relapse in patients with ANL, ALL, and CML transplanted in advanced disease. Among patients developing either acute or chronic GVHD, treatment failure (that is, mortality or relapse) was decreased in patients with ALL transplanted in relapse (RR = 0.70, P less than .033) and CML in blast crisis (RR = 0.37, P less than .009). This effect was independent of age, sex, preparative regimen, GVHD prophylaxis, or length of follow-up. Five-year actuarial estimates were derived for the subset of 657 patients who survived in remission 150 days after transplant and were at risk for development of chronic GVHD. Among patients with ANL in first remission or CML in chronic phase, GVHD had an adverse effect on survival and no apparent influence on relapse. Among patients with ANL and ALL transplanted in relapse, the probability of relapse after day 150 was 74% without [corrected] GVHD, 45% with acute and chronic GVHD, 35% with [corrected] only acute GVHD, and 34% with only chronic GVHD (P less than .001). Actuarial survival in these four GVHD groups was 25%, 34%, 59%, and 62%, respectively (P less than .009). Among patients with CML in acceleration or blast crisis, the probability of relapse after day 150 was 65% without GVHD and 36% with acute and/or chronic GVHD (P less than .017). We conclude that acute and chronic GVHD were associated with a durable antileukemic effect and improved survival in patients transplanted in advanced stages of ALL and CML.  相似文献   
425.
Untransfused dogs given 9.2 Gy total-body irradiation and hematopoietic grafts from DLA-identical littermate donors uniformly achieve sustained engraftment, whereas dogs given three transfusions (Tx) of whole blood from the intended marrow donor 24, 17 and 10 days pretransplant uniformly reject their graft. Sensitization appears to be mediated by peripheral blood mononuclear cells and can be prevented by prior irradiation of the Tx product with UV light, known to inactivate leukocytes, in particular, cells with accessory function. In the present study we investigated which leukocyte population was responsible for Tx-induced sensitization and subsequent marrow graft rejection. Surprisingly, neither monocytes nor macrophages or dendritic cells induced sensitization, and all dogs so treated achieved engraftment; however, all four evaluable dogs transfused with UV- exposed blood to which small numbers of normal dendritic cells (12.5 x 10(3)/kg) were added rejected their marrow graft. Among five dogs given UV-exposed blood and normal monocytes (12.5 x 10(3)/kg) only one rejected its graft, and four achieved sustained engraftment. We conclude that donor dendritic cells are necessary, albeit not sufficient for in vivo sensitization. Sensitization is prevented by elimination or inactivation of dendritic cell.  相似文献   
426.
Devising effective assessment techniques and therapy for movement disorders in young children requires in-depth measures of the child's perceptuo-motor functioning. It is argued that the field of movement disorders can benefit from an ecological approach to perception and action, where perception subserves action and action influences perception. Three notions central to the ecological approach are described and illustrated with our recent research on infant and child perceptual and motor behaviour.  相似文献   
427.
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