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41.
42.
Using the CD40 system, in vitro proliferation of hairy cell leukemia (HCL) was examined in 43 patients. In this culture system, cells were stimulated by interleukin-4 (IL-4) and anti-CD40 monoclonal antibodies (MoAbs) that were added in soluble form or were cross-linked via their Fc part using Fc gamma RII-transfected mouse fibroblast cells. Proliferation was induced and confirmed by 3H-thymidine incorporation in 14 cases and by the presence of metaphases in 42 cases. 3H-thymidine incorporation showed a heterogeneous pattern: cross-linking of anti- CD40 gave the highest proliferation in 8 cases; in 11 cases, stimulation with anti-CD40 MoAbs alone, without cross-linking also resulted in proliferation; the addition of IL-4 further enhanced 3H- thymidine incorporation in 5 cases, but suppressed this phenomenon in 5 other cases. The CD40 system proved to be very effective in obtaining cytogenetic data. With a success rate of 42 of 43 patients tested, we found clonal abnormalities in 8 cases (19%) and nonclonal abnormalities with involvement of one or two abnormal metaphases in another 7 cases. The chromosomes most frequently involved in the abnormal karyotypes, both structurally and numerically, were chromosomes 5, 7, and 14. By fluorescence-activated cell-sorting analysis of the cultured cells, and by immunophenotypic analysis of metaphase spreads, T-cell growth could be excluded and the HCL-lineage confirmed. Stimulation via the CD40 antigen is an excellent tool for growing hairy cell leukemia cells.  相似文献   
43.
Baldwin  GC; Golde  DW; Widhopf  GF; Economou  J; Gasson  JC 《Blood》1991,78(3):609-615
Hematopoietic growth factor receptors are present on cells of normal nonhematopoietic tissues such as endothelium and placenta. We previously demonstrated functional human granulocyte-macrophage colony- stimulating factor (GM-CSF) receptors on small cell carcinoma of the lung cell lines, and others have reported that certain solid tumor cell lines respond to GM-CSF in clonogenic assays. In the current study, we examine human melanoma cell lines and fresh specimens of melanoma to determine whether they have functional GM-CSF receptors. Scatchard analyses of 125I-GM-CSF equilibrium binding to melanoma cell lines showed a mean of 542 +/- 67 sites per cell with a kd of 0.72 +/- 0.14 nmol/L. Cross-linking studies in the melanoma cell line, M14, showed a major GM-CSF receptor species of 84,000 daltons. Under the conditions tested, the M14 cells did not have a proliferative response to GM-CSF in vitro, nor was any induction of primary response genes detected by Northern analysis in response to GM-CSF. Studies to determine internal translocation of the receptor-ligand complex indicated less than 10% of the 125I-GM-CSF internalized was specifically bound to receptors. Primary melanoma cells from five surgical specimens had GM-CSF receptors; Scatchard analysis was performed on one sample, showing 555 sites/cell with a kd of 0.23 nmol/L. These results indicate that human tumor cells may express a low-affinity GM-CSF receptor protein that localizes to the cell surface and binds ligand, but lacks functional components or accessory factors needed to transduce a signal.  相似文献   
44.
Background:  Van der Woude syndrome (VWS) is the most common clefting syndrome in humans. It is characterized by the association of congenital lower lip fistulae with cleft lip and/or cleft palate. VWS individuals have a high prevalence of hypodontia. Although caused by a single gene mutation, VWS has variable phenotypic expression. This study aimed to describe the range of clinical presentations in 22 individuals with VWS to facilitate its diagnosis.
Methods:  A retrospective study of 22 patients with a diagnosis of VWS was undertaken at the Australian Craniofacial Unit (ACFU) in Adelaide. Three extended families with affected members were included in the study cohort.
Results:  The overall prevalence of lip pits in this study cohort was 86%. Cleft phenotypes included bilateral cleft lip and palate (32%); unilateral cleft lip and palate (32%); submucous cleft palate (23%); and isolated cleft hard and soft palate (9%). Missing permanent teeth were reported in 86% of affected individuals.
Conclusions:  Submucous cleft palate in VWS may go undiagnosed if the lower lip pits are not detected. Associated hypodontia and resultant malocclusions will also require management by a dental team.  相似文献   
45.
目的:研究新的桂皮酰胺类衍生物,3-4二氯苯丙烯酰另丁胺(AED8801)对大鼠脑缺血/再灌注损伤的影响。方法:采用Pulsinelli四血管阻断大鼠脑缺血/再灌注模型,观察了AED8801对脑组织中水含量、氨基到含量、6-keto-PGF1α和TXB2含量,以及二者之比值的影响。结果:一AED8801能够降低脑缺血/再灌注大鼠所引起的脑水含量增加。二采用氨基酸自动分析仪进行检测,发现脑缺血/再灌  相似文献   
46.
47.

Objective

To test the hypothesis that fluid resuscitation in the ED with plasmalyte-148 (PL) compared with 0.9% sodium chloride (SC) would result in a lower proportion of patients with diabetic ketoacidosis (DKA) requiring intensive care unit (ICU) admission.

Methods

We performed a prespecified nested cohort study at two hospitals within a cluster, crossover, open label, randomised, controlled trial comparing the effects of PL versus SC as fluid therapy for patients who presented to the ED with DKA. All patients presenting within a fixed recruitment period were included. The primary outcome was the proportion of patients admitted to ICU.

Results

Eighty-four patients were enrolled (SC n = 38, PL n = 46). The SC group had a lower median pH on admission (SC: 7.09 [interquartile range (IQR) 7.01–7.21], PL: 7.17 [IQR 6.99–7.26]). The median volume of intravenous fluids administered in ED was 2150 mL (IQR 2000–3200 mL; SC) and 2200 mL (IQR 2000–3450; PL); respectively. A higher proportion of patients in the SC group, 19 (50%), was admitted to ICU compared with PL group, 18 (39.1%); however, after adjustment for pH at presentation and diabetes type in a multivariable logistic regression model, the PL group did not have a significantly different rate of ICU admission compared with the SC group (odds ratio for ICU admission 0.73, 95% confidence interval 0.13–3.97, P = 0.71).

Conclusion

Patients with DKA treated with PL compared with SC in the EDs had similar rates of requiring ICU admission.  相似文献   
48.
49.
Objective: Globally, depression is one of the most prevalent and burdensome conditions in older adults. However, there are few population-based studies of depression in older adults in developing countries. In this paper, we examine the prevalence of depressive symptoms and explore possible contributory risk factors in older adults living in Nepal.

Methods: A cross-sectional study was conducted in two semi-urban communities in Kathmandu, Nepal. Depression was assessed using the 15-item Geriatric Depression Scale in 303 participants, aged 60 years and over. Multivariate logistic regression was then used to assess associations between potential risk factors and depression.

Results: More than half of the participants (n = 175, 60.6%) had significant depressive symptomatology, with 27.7% having scores suggesting mild depression. Illiteracy (aOR = 2.01, 95% CI: 1.08–3.75), physical immobility (aOR = 5.62, 95% CI: 1.76–17.99), the presence of physical health problems (aOR = 1.97, 95% CI: 1.03–3.77), not having any time spent with family members (aOR = 3.55, 95% CI: 1.29–9.76) and not being considered in family decision-making (aOR = 4.02, 95% CI: 2.01–8.04) were significantly associated with depression in older adults.

Conclusion: The prevalence of depression was significant in older adults. There are clear associations of depression with demographic, social support and physical well-being factors in this population. Strategies that increase awareness in the community along with the health and social care interventions are needed to address the likely drivers of depression in older adults.  相似文献   

50.

Introduction

Mammographic density is known to be a strong risk factor for breast cancer. A particularly strong association with risk has been observed when density is measured using interactive threshold software. This, however, is a labour-intensive process for large-scale studies.

Methods

Our aim was to determine the performance of visually assessed percent breast density as an indicator of breast cancer risk. We compared the effect on risk of density as measured with the mediolateral oblique view only versus that estimated as the average density from the mediolateral oblique view and the craniocaudal view. Density was assessed using a visual analogue scale in 10,048 screening mammograms, including 311 breast cancer cases diagnosed at that screening episode or within the following 6 years.

Results

Where only the mediolateral oblique view was available, there was a modest effect of breast density on risk with an odds ratio for the 76% to 100% density relative to 0% to 25% of 1.51 (95% confidence interval 0.71 to 3.18). When two views were available, there was a considerably stronger association, with the corresponding odds ratio being 6.77 (95% confidence interval 2.75 to 16.67).

Conclusion

This indicates that a substantial amount of information on risk from percentage breast density is contained in the second view. It also suggests that visually assessed breast density has predictive potential for breast cancer risk comparable to that of density measured using the interactive threshold software when two views are available. This observation needs to be confirmed by studies applying the different measurement methods to the same individuals.  相似文献   
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