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51.
52.
Normal ovaries and functional cysts: MR appearance   总被引:6,自引:1,他引:5  
Outwater  EK; Mitchell  DG 《Radiology》1996,198(2):397
  相似文献   
53.
Dementia with Lewy bodies (DLB) accounts for 10–25% of all dementia cases in clinical populations and is considered to be the second most common degenerative dementia in elderly people after Alzheimer's disease (AD). Dementia with Lewy bodies is characterized by the presence of cognitive, psychiatric, and motor symptoms. Although the neuropsychological profiles of patients with DLB often differ from those of patients with AD, the diagnostic sensitivity, specificity, and predictive values of these profiles remain largely unknown. The present paper reviews the neuropsychological profiling of DLB and attempts the neuropsychological differentiation of DLB from AD.  相似文献   
54.
The aim of our study was to analyze circadian distribution of premature ventricular contractions (PVC) and its coupling interval (CI) in patients after orthotopic heart transplantation (HTx). Forty-two patients (5 females, 37 males) were monitored from 2 weeks to 5 years after HTx; 180 24-hour Holter ECG studies were performed. All recordings were divided into two groups: group I, within 1 month after HTX; and group II, after 1 month. Patients with more than 250 PVC/24 hours were selected for distribution of PVC and CI evaluation. Conclusions : Ventricular arrhythmias occur frequently in patients after heart transplantation. In patients with high Lown scale arrhythmias low occurrence (< 250/24 hours) of PVC was frequently observed (IVa: 81.8%; IVb: 84.7%). Similar patterns of circadian distribution (CD) of PVC and CD of HR in denervated heart after HTx suggest the influence of circulating catecholamines on their occurrence.  相似文献   
55.
Interleukin-8 (IL-8) is a chemoattractant cytokine involved in chemotaxis and activation of neutrophils. Because in vivo administration of IL-8 induces mobilization of hematopoietic stem cells in mice, we assessed the mobilizing properties of IL-8 in rhesus monkeys. Recombinant human IL-8 was administered as a single intravenous injection at doses of 10, 30, and 100 micrograms/kg to rhesus monkeys (age, 2 to 3 years; weight, 2.5 to 4.5 kg). Venous blood samples were obtained at time intervals ranging from 1 to 480 minutes after IL-8 administration. Cell counts, colony-forming unit-Mix assays, and fluorescence-activated cell sorter analysis were performed. Plasma was harvested to assess IL-8 levels. A time-controlled bolus intravenous injection of 100 micrograms IL-8 per kilogram of body weight resulted in peak IL-8 plasma levels up to 5 micrograms/mL. The calculated half-time life of free IL-8 was 9.9 +/- 2.2 minutes. IL-8 injection resulted in instant neutropenia that was due to pulmonary sequestration, as shown using 99mTc-labeled leukocytes. Within 30 minutes after IL-8 injection, neutrophilia developed with counts up to 10-fold greater than baseline levels. The numbers of hematopoietic progenitor cells (HPCs) increased from 45 +/- 48/mL to 1,382 +/- 599/mL of blood at 30 minutes after injection of 100 micrograms IL-8 per kilogram of bodyweight (mean +/- SD, n = 8). Individual animals showed 10- to 100-fold increase in numbers of circulating HPCs that returned to almost pretreatment values (92 +/- 52 CFU/mL) at 240 minutes after the injection of IL-8. Immunophenotyping showed no significant changes in lymphocyte (sub)populations. A second bolus injection of IL-8 with an interval of 72 hours resulted in similar numbers of mobilized stem cells as observed after the first injection, showing that no tachyphylaxis had occurred. We conclude that IL-8 induces mobilization of HPCs from the bone marrow of rhesus monkeys in a rapid and reproducible fashion. Therefore, IL-8 may be a potentially useful cytokine in the setting of blood stem cell transplantation.  相似文献   
56.
There is a long-standing controversy as to whether a single bone marrow (BM)-derived cell can differentiate along both hematopoietic and stromal lineages. Both primitive hematopoietic and stromal progenitor cells in human BM express the CD34 antigen but lack expression of other surface markers, such as CD38. In this study we examined the CD34+, CD38- fraction of human fetal BM by multiparameter fluorescence- activated cell sorting (FACS) analysis and single-cell sorting. CD34+, C38- cells could be divided into HLA-DR+ and HLA-DR- fractions. After single-cell sorting, 59% of the HLA-DR+ cells formed hematopoietic colonies. In contrast, the CD34+, CD38-, HLA-DR- cells were much more heterogeneous with respect to their light scatter properties, expression of other hematopoietic markers (CD10, CD36, CD43, CD49b, CD49d, CD49e, CD50, CD62E, CD90w, CD105, and CD106), and growth properties. Single CD34+, CD38-, HLA-DR- cells sorted into individual culture wells formed either hematopoietic or stromal colonies. The presence or absence of CD50 (ICAM-3) expression distinguished hematopoietic from stromal progenitors within the CD34+, CD38-, HLA-DR- population. The CD50+ fraction had light scatter characteristics and growth properties of hematopoietic progenitor cells. In contrast, the CD50- fraction lacked hematopoietic progenitor activity but contained clonogenic stromal progenitors at a mean frequency of 5%. We tested the hypothesis that cultures derived from single cells with the CD34+, CD38- , HLA-DR- phenotype could differentiate along both a hematopoietic and stromal lineage. The cultures contained a variety of mesenchymal cell types and mononuclear cells that had the morphologic appearance of histiocytes. Immunophenotyping of cells from these cultures indicated a stromal rather than a hematopoietic origin. In addition, the growth of the histiocytic cells was independent of the presence or the absence of hematopoietic growth factors. Based on sorting more than 30,000 single cells with the CD34+, CD38-, HLA-DR- phenotype into individual culture wells, and an analysis of 864 stromal cultures initiated by single CD34+ BM cells, this study does not support the hypothesis of a single common progenitor for both hematopoietic and stromal lineages within human fetal BM.  相似文献   
57.
Reddington  M; Novak  EK; Hurley  E; Medda  C; McGarry  MP; Swank  RT 《Blood》1987,69(5):1300-1306
Mepacrine uptake into platelets and bone marrow megakaryocytes was analyzed to further characterize the dense granule defects in a group of seven mouse pigment mutants that have characteristics of platelet storage pool disease (SPD). In contrast to our previous studies using electron microscopy, this method revealed that all mutants had normal numbers of dense granules. However, total mepacrine uptake in all mutant platelets was significantly diminished to less than 50% of normal uptake. Also, the flashing phenomenon observed when normal dense granules are irradiated with ultraviolet light was either greatly diminished or absent when platelets of individual mutants were similarly irradiated. Therefore the principal defect in the mutant platelets is an inability to accumulate dense granule contents rather than an absence of the granules. Mepacrine uptake into megakaryocytes was indistinguishable in normal and mutant mice. This indicates the mutant dense granule defects appear either very late in megakaryocyte development or early in platelet formation in correlation with development of the mature dense granule. By standard transmission electron microscopy we have not been able to detect gross structural or subcellular abnormalities in either platelets or megakaryocytes of mutant mice. It appears all seven mutants produce immature or functionally abnormal dense granules.  相似文献   
58.
59.
Acute right iliac fossa pain is a common surgical presentation. The presentation is often non-specific and encompasses a wide differential, which creates a diagnostic challenge. Ultrasound is commonly the initial cross-sectional imaging modality and can be used as a tool to triage patients appropriately; assessing for appendicitis and other salient findings, which may indicate an alternative condition. Additionally, the dynamic nature of this imaging modality enables patient interaction. Following a systematic assessment of the abdomen and pelvis, a more focused interrogation of the right iliac fossa is performed. In this pictorial review, we illustrate the sonographic features of appendicitis and other conditions that can mimic appendicitis in its presentation. This highlights that through a systematic approach, it is possible to distinguish between these different pathologies, enabling clinicians to optimally manage the patient.  相似文献   
60.
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