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51.
Expression of T cell receptor delta chains in benign and malignant T lineage lymphoproliferations 总被引:4,自引:3,他引:4 下载免费PDF全文
Recent studies in both human and murine systems have demonstrated the existence of a second CD3-associated T cell receptor (the gamma delta-TCR) distinct from the alpha beta heterodimer associated with antigen recognition by classical T cells. Using a monoclonal antibody specific for the delta component of the human gamma delta-TCR, the expression of this antigen in both benign, reactive lymphoid tissues and T lineage lymphomas was studied with immunohistologic techniques. In the normal thymus, TCR-delta+ cells constituted less than 5% of the CD3+ thymocytes and were located primarily in the medulla or juxtamedullary cortex. Within the T zones of 16 histologically varied reactive peripheral lymphoid tissues, including four patients with marked predominantly paracortical hyperplasia, the authors identified from less than 1% to a maximum of 5% TCR-delta+ cells. While these results are consistent with the hypothesis that TCR-gamma delta+ cells comprise a small distinct subpopulation of peripheral T cells in humans, selective localization or recruitment of these cells could not be demonstrated in any of a number of tissues or reactive situations. Among 62 T lineage lymphomas, including 14 CD3+/TCR-beta- cases, only two TCR-delta+ neoplasms were identified, both lymphoblastic lymphomas displaying the CD3+/CD4-/CD8- phenotype known to be associated with normal TCR-gamma delta+ T cells. Because the majority of CD3+/TCR-beta- lymphomas did not display TCR-delta, these results argue against the hypothesis that the high incidence of CD3/TCR-beta discordance noted in T lineage lymphomas represents preferential transformation of the TCR-delta-expressing subset. 相似文献
52.
Comparison of "host cell infiltrates" in patients with follicular lymphoma with and without spontaneous regression 总被引:1,自引:0,他引:1
J G Strickler C M Copenhaver V A Rojas S J Horning R A Warnke 《American journal of clinical pathology》1988,90(3):257-261
The "host cell infiltrates" in five patients with low-grade follicular lymphoma who had spontaneous regression without therapy were studied with the use of immunohistochemical methods applied to frozen sections. These infiltrates were compared with the "host cell infiltrates" in six patients with follicular lymphoma with progressive disease. The group with progressive disease was selected to be similar to the group with spontaneous regression in age, sex, histologic characteristics, and stage of disease. The patients with spontaneous regression had significantly more T-helper cells in the host cell infiltrate than the control patients. There were no statistically significant differences between the two groups in numbers of cytotoxic/suppressor T-cells, macrophages, Tac-positive cells, Leu-7-positive cells, or proliferating cells. 相似文献
53.
Diffuse malignant lymphoma with cerebriform nuclei: A B-cell lymphoma studied with monoclonal antibodies 总被引:2,自引:0,他引:2
J S Burke R A Warnke J M Connors J H Beckstead 《American journal of clinical pathology》1985,83(6):753-759
A lymph node biopsy performed on a 55-year-old woman with asymptomatic generalized lymphadenopathy revealed a diffuse, malignant lymphoma composed of small to intermediate-sized lymphocytes with cerebriform-shaped nuclei; electron microscopy confirmed the nuclear complexity. The cerebriform nuclear configuration, coupled with an interfollicular pattern of nodal involvement with encroachment upon residual germinal centers, was presumptive of either mycosis fungoides or a peripheral T-cell lymphoma. Immunologic evaluation, however, indicated that the cerebriform lymphocytes represented a monoclonal B-cell population (IgM-IgD, lambda). Staining with monoclonal antibodies disclosed a phenotype of Ia+, B1+, BA-1+, BA-2+, Leu-1+; the neoplastic cells were unreactive with T-cell, lineage-specific antibodies (anti-Leu-2a, -3a, -4, -5) and with J5 (CALLA). In light of the immunophenotype and the distributional pattern, the cerebriform-shaped lymphocytes may represent an extreme morphologic variant of intermediate lymphocytic lymphoma. 相似文献
54.
Frequent immunoglobulin and T-cell receptor gene rearrangements in "histiocytic" neoplasms 总被引:3,自引:5,他引:3 下载免费PDF全文
L. M. Weiss M. J. Trela M. L. Cleary R. R. Turner R. A. Warnke J. Sklar 《The American journal of pathology》1985,121(3):369-373
The authors have analyzed the DNA of immunoglobulin and T-cell receptor genes in a series of 6 malignancies which were judged to be of histiocytic derivation on the basis of morphologic criteria. They found that 4 of these cases showed rearrangements of the beta T-cell receptor genes in spite of the lack of any specific immunohistochemical markers for B or T cells. One case showed rearrangements of both heavy and light chain immunoglobulin genes and probably represents either a sinusoidal large cell lymphoma or a B-cell lymphoma with activation of histiocytes simulating malignant histiocytosis. A single case lacked both immunoglobulin and T-cell receptor rearrangements consistent with immunologic analyses that suggested its origin from an interdigitating reticulum cell. The result of this study in conjunction with the authors' previous immunologic observations suggests that many presumed histiocytic malignancies actually represent T-cell lymphomas. Alternatively, beta T-cell receptor rearrangement may be a common feature of tumors that show monocyte/histiocytic differentiation. 相似文献
55.
The use of stereotactic methods for the resection of subcortical lesions is heavily advocated in clinical neurosurgery introducing the term "neuronavigation". Though being an unequivocally elegant technique for the localisation and delineation of pathological lesions in the central nervous system neuronavigation has not been validated by any prospective randomized controlled trial. The method is prone to significant errors as to the intraoperative localisation based upon preoperative three-dimensional images. The maximum error can be up to 2.6 cm depending on the extent of the so-called brain shift. In comparison classical frame based stereotaxy has a mean error of +/- 1 mm and remains the gold standard for the exact three-dimensional localisation of a given lesion. The value of neuronavigation is evident for small deep seated vascular lesions. For metastatic tumors or skull base tumors the usefulness is rather marginal because alternative therapies are available with proven and equivalent efficacy and reduced morbidity on one hand, and because of the anatomy of the tumor which makes neuronavigation unnecessary. For the currently most common application of neuronavigation, i.e. surgery of gliomas, no significant improvements of therapeutic results can be expected from neuronavigation. The biology of gliomas limits any mechanical approaches. 相似文献
56.
Ranheim EA Jones C Zehnder JL Warnke R Yuen A 《The American journal of surgical pathology》2000,24(2):296-301
Primary T-cell lymphoma of the gastrointestinal tract is a rare and usually aggressive disorder that may be associated with celiac disease. The authors describe a unique case of a clonal proliferation of CD8+ T cells involving the oral mucosa, ileum, and colon of a 35-year-old man that has regressed spontaneously and recurred numerous times over a 9-year period without treatment. The patient's symptoms were limited to occasional rectal bleeding and recurring painful oral ulcers. Within the intestine, these collections of small T cells induced minimal architectural distortions and did not show extensive epitheliotrophism. Polymerase chain reaction and sequencing analyses revealed that the identical T-cell clone has been present for more than 9 years and in different mucosal locations in this patient. This may represent a unique T-cell lymphoproliferative process akin to a mucosal counterpart of lymphomatoid papulosis of the skin. 相似文献
57.
58.
Objective: To identify factors that influence a woman's decision to breast-feed.
Methodology: Five hundred and fifty-six women were recruited from the maternity wards of two Perth hospitals. Data were collected from a self-administered questionnaire completed by participants prior to discharge. Logistic regression analysis was used to determine factors influencing the initiation of breast-feeding.
Results: At discharge from hospital 83.8% of women were breast-feeding, including 6% who were giving complementary formula feeds. After controlling for potentially confounding demographic and biomedical factors, the father's reported preference for breast-feeding was found to be the most important factor influencing a woman's decision to breast-feed (OR 10.18).
Conclusion: Fathers participate in and influence the choice of infant feeding method and should be included in breast-feeding discussions. 相似文献
Methodology: Five hundred and fifty-six women were recruited from the maternity wards of two Perth hospitals. Data were collected from a self-administered questionnaire completed by participants prior to discharge. Logistic regression analysis was used to determine factors influencing the initiation of breast-feeding.
Results: At discharge from hospital 83.8% of women were breast-feeding, including 6% who were giving complementary formula feeds. After controlling for potentially confounding demographic and biomedical factors, the father's reported preference for breast-feeding was found to be the most important factor influencing a woman's decision to breast-feed (OR 10.18).
Conclusion: Fathers participate in and influence the choice of infant feeding method and should be included in breast-feeding discussions. 相似文献
59.
OBJECTIVE: Most neonatologists include an apnea-free period in the criteria for the discharge of preterm infants. However, the length of time one should wait after the cessation of apnea before sending an infant home without a monitor is debated. We undertook this study in an attempt to define a minimal and safe observation period between the time of the last apnea episode and discharge. METHODS: We reasoned that in infants with idiopathic apnea of prematurity, the intervals between days on which apnea occurs gradually increase until some point at which clinically significant apnea ceases. Therefore, knowledge about the intervals between days on which apnea occurred just before the last apnea would provide a reasonable estimate of the minimal safe observation interval between the last apnea and discharge. We reviewed the charts of 266 infants born in 1993 and 1994 at =32 weeks' gestational age or weighing =1500 g at birth from two institutions to determine the intervals between the day on which the last apnea occurred and the previous two days on which apnea occurred. One hundred seventy-five infants were excluded because they never experienced apnea, or data about the last apnea was missing, or they were on xanthines during the period encompassing the last 3 apnea days, or they weighed <1500 g or were <34 weeks' postmenstrual age at the time of the last apnea. Of the 91 remaining infants, gestational age at birth, birth weight, 1- and 5-minute Apgar scores, and discharge weight were not different between the two institutions. For each infant we determined the longest of the intervals between the 2 days on which apnea occurred previous to the day of the last apnea (MAXINT for maximum interval). The infants were then ordered by MAXINT and, starting at the longest MAXINT, the medical records of each infant were carefully examined for other conditions known to be associated with apnea (eg, recovering from anesthesia, sepsis, chronic lung disease, and so forth). The minimal safe observation period was then defined as the longest MAXINT in which there was at least 1 infant with no other explanation for the apnea other than prematurity. RESULTS: The median duration of the intervals between the 2 days on which apnea occurred previous to the day on which the last apnea occurred were 3. 0 and 2.0 days and the median duration of the MAXINT was 4.0 days. On careful examination of the charts, it was determined that each of 13 infants with a MAXINT preceding the day on which the last apnea occurred of greater than 8 days had some other condition that might result in apnea, including residual lung disease, sepsis, surgery, and so forth. In contrast, among the group of infants with a MAXINT of =8 days, at least 1 infant at each MAXINT (eg, 1 to 8) had significant apnea with no other explanation other than prematurity. CONCLUSIONS: We conclude that otherwise healthy preterm infants continue to have apneas separated by as many as 8 days before the last apnea before discharge. Conversely, infants with longer apnea intervals often have identifiable risk factors other than apnea of prematurity. 相似文献
60.