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91.
92.
Although the prevention of unintended adolescent pregnancy is a primary goal of the American Academy of Pediatrics and society, many adolescents continue to become pregnant. Since the last statement on adolescent pregnancy was issued by the Academy in 1989, new observations have been recorded in the literature. The purpose of this new statement is to review current trends and issues on adolescent pregnancy to update practitioners on this topic.  相似文献   
93.
94.
Telen  MJ; Rao  N; Udani  M; Thompson  ES; Kaufman  RM; Lublin  DM 《Blood》1994,84(9):3205-3211
Cromer blood group antigens reside on the complement regulatory protein decay accelerating factor (DAF, CD55). This glycosyl- phosphatidylinositol-anchored glycoprotein is widely distributed, especially among cell types in contact with plasma. Numerous Cromer blood group antigens have been defined using alloantibodies induced by transfusion or pregnancy. However, few pairs of antithetical antigens have been described in this system, presumably because of the rarity of the low-frequency alleles. Analysis of polymerase chain reaction- amplified genomic DNA showed that the Cr(a-) phenotype has a Ala193-- >Pro substitution in short consensus repeat 4 (SCR4) of DAF, and the Tc(a-b+) phenotype has a Arg18-->Leu substitution in SCR1 of DAF. The locations of Cra and Tca epitopes were confirmed by analysis of Chinese hamster ovary cell transfectants expressing a Cr(a-) allele-specific transfectant and a chimeric protein containing only SCR1 of DAF, respectively. Overall, these studies further show the usefulness of an approach based on recombinant proteins in mapping blood group antigen epitopes and identifying blood group antibodies.  相似文献   
95.
Haddy  TB; Keenan  AM; Jaffe  ES; Magrath  IT 《Blood》1988,72(4):1141-1147
Of 95 young non-Hodgkin's lymphoma patients entered consecutively on the National Cancer Institute (NCI) Protocol 7704, 26 (27.4%) had involvement of one or more bones. The mean age of these 26 patients was 16.6 years, and the male to female ratio was 3.3:1. Tumor histology included undifferentiated Burkitt's lymphoma in 12, undifferentiated non-Burkitt's lymphoma in two, undifferentiated, unspecified lymphoma in one, diffuse large cell lymphoma in three, and lymphoblastic lymphoma in eight patients. Most had extensive disease; two patients had isolated bone lesions, one had lesions of two bones without involvement of other tissues, and 23 had either multiple bone lesions or single bone lesions with involvement of other tissues. Eight of the 26 patients had bone marrow involvement. Of a subgroup of 12 patients with jaw disease, 11 had undifferentiated lymphoma and one had diffuse large cell lymphoma. Only one had primary a jaw tumor, with two quadrants of the jaw involved. All 26 patients were treated with chemotherapy; only two received radiotherapy initially for bone lesions. Predicted survival of the 26 patients at 5 years is 53.2%. The 12 patients who remain disease free have a mean survival of 62.1 months (range, 22 to 100 months). Our results call into question the role of radiotherapy in the treatment of bone lesions in non-Hodgkin's lymphoma.  相似文献   
96.
We identified eight cases of T-cell lymphoma with evidence of a gamma delta phenotype over a 13-year period. Seven of these cases conformed to a distinct clinicopathologic entity of hepatosplenic gamma delta T- cell lymphoma. Nearly all of these patients were young adult males (five of seven), with a median age at presentation of 20 years. They presented with marked hepatosplenomegaly, without lymphadenopathy or significant peripheral blood lymphocytosis. Thrombocytopenia was seen in all patients, and five of seven were mildly anemic. The clinical course was aggressive, and despite multiagent chemotherapy, the median survival duration was less than 1 year. The morphologic findings were uniform; a monomorphic population of medium-sized lymphoid cells with moderately clumped chromatin and a rim of pale cytoplasm infiltrated the sinusoids of the spleen, liver, and bone marrow. The cells had a characteristic immunophenotype: CD2+, CD3+, CD4-, CD5-, CD7+, CD16+, CD57-, CD25-, T-cell receptor (TCR)delta +, beta F1-. CD8 was positive in four of seven cases tested, and CD56 was positive in five of six. All cases expressed the cytotoxic granule-associated protein, TIA1, but perforin was detected in only one case. All cases with assessable DNA had a TCR gamma gene rearrangement, and lacked Epstein-Barr virus sequences. Isochromosome 7q was identified in two cases with cytogenetic information. The one case of cutaneous gamma delta T-cell lymphoma differed in its clinical manifestations, histologic appearance, and immunophenotype. We conclude that hepatosplenic gamma delta T-cell lymphoma is a distinct clinicopathologic entity derived from cytotoxic gamma delta T cells, and should be distinguished from other lymphomas of T-cell and natural-killer cell (NK)-like T-cell derivation.  相似文献   
97.
The t(11;14)(q13;q32) translocation and its molecular counterpart bcl-1 rearrangement are frequently associated with mantle cell lymphomas (MCLs) and only occasionally with other variants of B-cell lymphoid malignancies. This translocation seems to activate the expression of PRAD-1/cyclin D1 gene located downstream from the major breakpoint cluster region of this rearrangement. However, the possible overexpression of this gene in other lymphoproliferative disorders independently of bcl-1 rearrangement is unknown. We have examined the overexpression of PRAD-1 gene in a large series of 142 lymphoproliferative disorders including 20 MCLs by Northern blot analysis. Cytogenetic and/or bcl-1 rearrangement analysis with 2 probes (MTC, p94PS) were performed in 28 cases. Strong PRAD-1 overexpression was observed in 19 of the 20 MCLs including 3 gastrointestinal forms and 4 blastic variants. t(11;14) and/or bcl-1 rearrangement was detected in 6 of the 12 MCLs examined. No correlation was found between the different levels of mRNA expression and the pathologic characteristics of the lymphoma. Among chronic lymphoproliferative disorders other than MCL, only 1 atypical chronic lymphocytic leukemia (CLL) with a t(11;14) translocation and bcl-1 rearrangement and the 2 hairy cell leukemias (HCLs) analyzed showed upregulation of PRAD-1 gene. The expression in the 2 HCLs was lower than in MCL, and no bcl-1 rearrangement was observed. These findings indicate that PRAD-1 overexpression is a highly sensitive and specific molecular marker of MCL but it may also be upregulated in some B-CLLs and in HCL.  相似文献   
98.
In this review, we will describe the immunopathogies of immune reconstitution inflammatory syndrome, IRIS. IRIS occurs in a small subset of HIV patient, initiating combination antiretroviral therapy (ART), where immune reconstitution becomes dysregulated, resulting in an overly robust antigen‐specific inflammatory reaction. We will discuss IRIS in terms of the associated coinfections: mycobacteria, cryptococci, and viruses.  相似文献   
99.
100.
Sparano  JA; Wiernik  PH; Strack  M; Leaf  A; Becker  N; Valentine  ES 《Blood》1993,81(10):2810-2815
Fourteen patients with poor-prognosis intermediate- to high-grade non- Hodgkin's lymphoma (NHL) associated with human immunodeficiency virus (HIV) infection (12 patients) or human T-cell leukemia virus type I (HTLV-I) infection (two patients) received cyclophosphamide 750 mg/m2, doxorubicin 50 mg/m2, and etoposide 240 mg/m2 administered as a continuous intravenous (IV) infusion over 4 days (infusional CDE); treatment was repeated every 28 or more days for up to six cycles. All HIV-positive patients had at least one poor prognostic feature, which included either extranodal disease (10 patients), Karnofsky performance status less than 70% (six patients), a CD4 count less than 100/microL (six patients), or a prior history of acquired immunodeficiency syndrome (AIDS; one patient). Both HTLV-I-positive patients had an elevated serum lactate dehydrogenase (LDH) level, a poor prognostic feature in that setting. Complete response (CR) occurred in 10 patients (71%; 95% confidence interval, 48% to 95%) and partial response (PR) occurred in three patients (21%), yielding an overall objective response rate of approximately 93%. The estimated Kaplan-Meier median survival was 17.4 months; seven of 12 HIV-positive patients are alive and disease-free with a median follow-up of 15 months (range, 7 to 24 months). Hospitalization was required after 19% of treatment cycles due to fever associated with granulocytopenia. Documented or suspected opportunistic infection occurred in five patients (36%), bacteremia occurred in three patients (21%), and candidemia occurred in one patient (7%). There was one treatment-related death attributable to disseminated aspergillosis. This pilot study suggests that infusional CDE may be a highly active regimen capable of producing durable remissions in a high proportion of patients with HIV-related NHL. Further study is required to confirm this observation.  相似文献   
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