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51.
Different proliferative activity of the glandular and myoepithelial lineages in benign proliferative and early malignant breast diseases. 总被引:3,自引:0,他引:3
Agnes Bánkfalvi Andreas Ludwig Bettina De-Hesselle Horst Buerger Igor B Buchwalow Werner Boecker 《Modern pathology》2004,17(9):1051-1061
The aim of the present study was to explore cell biological characteristics of normal breast, benign proliferative breast diseases and noninvasive breast malignancies based on the recently published adult progenitor cell concept from our group. Here, we investigated the proliferative activity of CK5/14(+), CK8/18/19(+) and alpha-smooth muscle actin(+) cellular phenotypes encountered in normal mammary gland, in a series of usual ductal hyperplasias and early malignant breast diseases, such as atypical ductal and lobular hyperplasias, as well as ductal and lobular in situ carcinomas. Immunohistochemical double labeling was performed on frozen sections from diagnostic breast biopsies by using antibodies to basal cytokeratins (CK5/14), glandular cytokeratins (CK8/18/19), smooth muscle actin and the Ki-67 antigen (MIB1). Normal breast tissues and usual ductal hyperplasias were characterized by a heterogeneous cellular composition of the growth fraction. The proliferative cell compartment consisted of CK8/18/19(+) glandular and, in a variable proportion, CK5/14(+) progenitor phenotypes. In contrast, noninvasive breast malignancies were composed of a monotonous proliferation of CK 8/18/19(+) neoplastic glandular cells. These findings indicate a significant role of progenitor cells in the development of benign proliferative breast diseases and lend support to the view that malignant transformation in the human breast usually occurs in a cell committed to the glandular lineage. Our results provide cell kinetic support to the functional progenitor cell hypothesis, and we propose this concept as an operative model for understanding benign proliferative and malignant breast diseases. 相似文献
52.
The main purpose of this communication is to alert nuclear medicine departments to the fact that the earlier version of the water phantom grossly overestimates soft-tissue attenuation in the neck, resulting in calculated thyroid uptake values which are significantly overestimated (in hyperthyroid patients we noted uptake values approaching or exceeding 100%). We believe that the solid Lucite phantom (which is the one recommended by IAEA) better approximates the human neck soft tissue overlying the thyroid. Institutions that continue to use the water phantom should be aware that their thyroid uptakes will be relatively elevated and the normal range must be shifted accordingly. Our normal range is 10%-30% uptake of 123I at 24 hr for the Lucite phantom. For the water phantom, the estimated normal range would be 15%-45%. In addition, the phantom type should be considered when comparing uptake results with those from another institution for a particular patient. Also, treatment doses for Grave's disease could be significantly affected, if such doses are calculated by a formula that depends on uptake. 相似文献
53.
Hubert A. Shaffer Jr. M.D. Donald A. Eckard Eduard E. de Lange M. R. Ramakrishnan 《Abdominal imaging》1988,13(1):221-223
Hypersensitivity reactions occurring during barium studies of the gastrointestinal tract are rare. A case is presented with radiographically demonstrated angioedema in the stomach and small bowel accompanied by allergic rhinitis, which was apparently an allergic response to the barium sulfate suspension. The reaction was documented twice during separate challenges to the barium suspension performed several months apart. 相似文献
54.
55.
Arend Bökenkamp Bettina Bohnhorst Christian Beier Norbert Albers Gisela Offner Johannes Brodehl 《Pediatric nephrology (Berlin, Germany)》1994,8(2):181-185
Gingival hyperplasia is a common side-effect of immunosuppression with cyclosporine A. Nifedipine is often used to control hypertension in kidney graft recipients. Analysis of gingival status in 106 children transplanted at our centre, and treated either with azathioprine, cyclosporine A or both, revealed significantly higher degrees of gingival overgrowth in those children receiving a combination of cyclosporine A and nifedipine compared with those children treated with cyclosporine A or nifedipine alone. Seven children undergoing gingivectomy at our centre over the past few years had received this combination. After a change in the antihypertensive regimen, avoiding long-term nifedipine medication, and improved dental care with chlorhexidine gel, we noted a reduction in the degree of gingival hyperplasia. In the majority of patients, nifedipine could be replaced by a single drug, usually hydralazine. We therefore recommend avoiding calcium channel blockers in the long-term management of hypertension in patients receiving cyclosporine. 相似文献
56.
Mobilization and evolutionary history of miniature inverted-repeat transposable elements (MITEs) in Beta vulgaris L. 总被引:1,自引:0,他引:1
Gerhard Menzel Daryna Dechyeva Heiko Keller Cornelia Lange Heinz Himmelbauer Thomas Schmidt 《Chromosome research》2006,14(8):831-844
We have identified three families of miniature inverted-repeat transposable elements (VulMITEs) in the genome of sugar beet
(Beta vulgaris L.), evidently derived from a member of the Vulmar family of mariner transposons. While VulMITEs I are typical stowaway-like MITEs, VulMITEs II and VulMITEs III are rearranged stowaway elements of increased size. The integration of divergent moderately and highly repetitive sequences into VulMITEs II and,
in particular in VulMITEs III, respectively, shows that amplification of repetitive DNA by MITEs contribute to the increase
of genome size with possible implications for plant genome evolution. Fluorescent in-situ hybridization (FISH), for the first time visualizing stowaway MITE distribution on plant chromosomes, revealed a dispersed localization of VulMITEs along all B. vulgaris chromosomes. Analysis of the flanking sequences identified a dispersed repeat as target site for the integration of the stowaway element VulMITE I. Recent transposition of VulMITE I, which most likely occurred during the domestication of cultivated beets, was concluded from insertional polymorphisms between
different B. vulgaris cultivars and species.
†Sequence data from this article have been deposited in the EMBL/GenBank Data Library under the accession nos. AM231630-AM231653
and AM259123-AM259125. 相似文献
57.
Effects of vitamin D and calcium supplementation on falls: a randomized controlled trial. 总被引:21,自引:0,他引:21
Heike A Bischoff Hannes B St?helin Walter Dick Regula Akos Margrith Knecht Christian Salis Matthias Nebiker Robert Theiler Michael Pfeifer Bettina Begerow Robert A Lew Martin Conzelmann 《Journal of bone and mineral research》2003,18(2):343-351
Specific receptors for vitamin D have been identified in human muscle tissue. Cross-sectional studies show that elderly persons with higher vitamin D serum levels have increased muscle strength and a lower number of falls. We hypothesized that vitamin D and calcium supplementation would improve musculoskeletal function and decrease falls. In a double-blind randomized controlled trial, we studied 122 elderly women (mean age, 85.3 years; range, 63-99 years) in long-stay geriatric care. Participants received 1200 mg calcium plus 800 IU cholecalciferol (Cal+D-group; n = 62) or 1200 mg calcium (Cal-group; n = 60) per day over a 12-week treatment period. The number of falls per person (0, 1, 2-5, 6-7, >7 falls) was compared between the treatment groups. In an intention to treat analysis, a Poisson regression model was used to compare falls after controlling for age, number of falls in a 6-week pretreatment period, and baseline 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D serum concentrations. Among fallers in the treatment period, crude excessive fall rate (treatment - pretreatment falls) was compared between treatment groups. Change in musculoskeletal function (summed score of knee flexor and extensor strength, grip strength, and the timed up&go test) was measured as a secondary outcome. Among subjects in the Cal+D-group, there were significant increases in median serum 25-hydroxyvitamin D (+71%) and 1,25-dihydroxyvitamin D (+8%). Before treatment, mean observed number of falls per person per week was 0.059 in the Cal+D-group and 0.056 in the Cal-group. In the 12-week treatment period, mean number of falls per person per week was 0.034 in the Cal+D-group and 0.076 in the Cal-group. After adjustment, Cal+D-treatment accounted for a 49% reduction of falls (95% CI, 14-71%; p < 0.01) based on the fall categories stated above. Among fallers of the treatment period, the crude average number of excessive falls was significantly higher in the Cal-group (p = 0.045). Musculoskeletal function improved significantly in the Cal+D-group (p = 0.0094). A single intervention with vitamin D plus calcium over a 3-month period reduced the risk of falling by 49% compared with calcium alone. Over this short-term intervention, recurrent fallers seem to benefit most by the treatment. The impact of vitamin D on falls might be explained by the observed improvement in musculoskeletal function. 相似文献
58.
J. Labadie M. J. D. van Tol N. H. Dijkstra M. van der Kaaden C. M. Jol van der Zijde G. G. de Lange F. E. Zwaan J. M. Vossen 《British journal of haematology》1992,82(2):437-444
A rapid recovery of specific humoral immunity in the recipient of an allogeneic bone marrow transplantation (BMT) can be observed after immunization of the donor before graft sampling. This has been attributed to transfer of specific immunity from donor to recipient. However, to maintain the concept of transfer the origin of the antibody producing cells in the recipient after BMT must be demonstrated. To this end, donor-recipient pairs with differences in Gm-allotypes were selected and immunized before BMT with the neo-antigen Helix pomatia haemocyanin (HPH) according to three immunization protocols. Additionally, the recipients were immunized at day 42 after BMT. Serum samples were weekly obtained from the recipients in the first 100 d after BMT. The origin of HPH-specific antibody producing cells was assessed by two approaches: (1) determination of the Gm-allotypes of anti-HPH antibodies within a distinct IgG subclass, (2) analysis of anti-HPH antibody spectrotypes by isoelectric focusing combined with immunoblotting. The results obtained with these two approaches show concordance in most instances and led to the conclusion that the antibody producing cells are of donor origin. 相似文献
59.
Leoncio Garrido Bettina Pfleiderer Bruce G. Jenkins Carol A. Hulka Daniel B. Kopans 《Magnetic resonance in medicine》1994,31(3):328-330
Studies using magnetic resonance spectroscopy in human volunteers to evaluate their livers in vivo and to analyze their blood in vitro suggest that there are measurable amounts of silicon compounds in the blood of some women with implants and that there is migration of silicone to other organs such as the liver. 相似文献
60.