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91.
92.
Detecting fetomaternal hemorrhage: a comparison of five methods   总被引:3,自引:0,他引:3  
Appropriate postpartum administration of Rh immune globulin relies on sensitive detection and accurate quantitation of fetomaternal hemorrhage (FMH). Recently, the microscopic Du test (micro Du) enhanced with polyethylene glycol (PEG Du) and flow cytometry (FC) have been advocated for this purpose. Three qualitative methods (micro Du, rosette test, and PEG Du) and two quantitative methods (acid elution and FC) for assessing FMH were evaluated with particular attention given to PEG Du and FC. In vitro studies comprised 10 series of dilutions of D+ cord cells in D- adult cells to yield D+ cell concentrations of 0.06, 0.12, 0.25, 0.50, 0.75, 1.0, and 2.0 percent. Additionally, 26 postpartum samples were tested. Of the qualitative techniques, the micro Du test was the least sensitive with 20 percent false-negative results occurring at 0.5 percent fetal cells. The PEG Du test was only slightly more sensitive and offered no clinical advantage. The rosette test was the most sensitive, consistently detecting fetal cells at concentrations of 0.25 percent or greater. FC and acid elution showed similar results, with good correlation obtained between measured and expected quantities of fetal cells (r = 0.99 and 0.96, respectively). One of 26 postpartum samples was positive by all screening techniques; acid elution and FC detected 0.3-percent concentrations of fetal cells and 0.17-percent concentrations of D+ cells, respectively. Although acid elution is a more commonly used method for quantitating FMH, FC offers an acceptable alternative that is capable of analyzing large numbers of cells with objectivity and reproducibility.  相似文献   
93.
目的:分析辽西地区农村汉族青少年的体型发育规律和特点,为体质人类学补充必要的数据。对象:按整群分层抽样法,抽取2001-07/2003-09辽西地区锦州、盘锦、葫芦岛、义县和绥中的农村13所中小学7~19岁经学校正常体质检查证明身体健康的汉族学生为调查对象,按性别分两大组,每大组按年龄分12小组,7~18岁每岁为1个年龄组,18~19岁为1个年龄组,每小组44~82人,共分24组,搜集完整资料1280名(男666名,女614名)。采用Heath-Carter体型法,每项指标测量2次,取平均值,10项指标由专人负责,测试数据按年龄和性别在微机中建立数据库,依次计算出各年龄组的内因子、中因子和外因子,体型图上的X,Y坐标值,身高/体质量1/3,样本中平均体型点到所有体型点空间距离的均数,三维空间中两个体型点间的差异,体脂百分比和各类体型分布频数。结果:参加调查1280名,均进入结果分析。①7~17岁青少年身高、体质量随年龄的增加而增长。平均身高、体质量男生大于女生。身高/体质量1/3指数除7、8、10、12和13岁外,各年龄组男生>女生,平均值男生>女生。体脂含量除8岁外,其他年龄组女生>男生,平均值女生>男生。②男生的体型均值3.6-2.5-3.7,属外胚层-内胚层均衡体型,女生平均体型值为4.3-2.2-3.3,属于偏外胚层的内胚层体型。体型频数的变化提示辽西农村汉族男生体型分布在内胚层和外胚层的体型较多,女生分布较集中,主要在内胚层体型。③内因子男生在3.0~4.0,女生在3.5~5.2,各年龄组女生>男生;中因子男生在1.6~3.9,女生在0.8~3.4,除7、11和17岁女生>男生外,其他年龄组男生>女生或男女相等,平均值男生>女生。外因子男生在3.0~5.0,女生在3.0~4.1,7、8、10、12、13岁女生>男生,11、14、15、16、17、18岁男生>女生。因此,女生的内因子占优势,皮下脂肪更发达,体态丰满,男生中因子占优势,骨骼粗壮,肌肉发达,随着年龄的增长,男生的身体相对瘦高程度增长,身材修长。④男女各年龄组间体型比较,7,8,9,10,11,12,13,14,15,16,17,18~19岁三维空间中两个体型点间的差异值分别为0.45,0.67,1.03,0.56,0.76,0.30,0.93,2.60,1.86,1.37,1.21,1.47,8~11岁年龄组男女间体型差异有显著性(t=2.66,2.75,2.95,3.58,P<0.05)。⑤与城市青少年相比,农村青少年身高低5~6cm(男女分别为u=6.24,5.90,P<0.01),体质量低3~6kg(男女分别为u=6.93,4.60,P<0.01)。结论:辽西地区农村男生较女生骨骼粗壮,肌肉发达,女生的皮下脂肪更发达,体态丰满,随着年龄的增长,男生的身体相对瘦高,身材修长。与城市青少年相比,农村青少年仍矮瘦,与国外资料和国内少数民族相比,辽西地区农村汉族青少年骨骼肌肉欠发达,身材修长。  相似文献   
94.
We describe the effects of 4-hydroperoxycyclophosphamide (4-HC) on the hematopoietic and stromal elements of human bone marrow. Marrow cells were exposed to 4-HC and then assayed for mixed (CFU-Mix), erythroid (BFU-E), granulomonocytic (CFU-GM), and marrow fibroblast (CFU-F) colony-forming cells and studied in the long-term marrow culture (LTMC) system. The inhibition of colony formation by 4-HC was dose and cell- concentration dependent. The cell most sensitive to 4-HC was CFU-Mix (ID50 31 mumol/L) followed by BFU-E (ID50 41 mumol/L), CFU-GM (ID50 89 mumol/L), and CFU-F (ID50 235 mumol/L). In LTMC, a dose-related inhibition of CFU-GM production was noted. Marrows treated with 300 mumol/L 4-HC were completely depleted of CFU-GM but were able to generate these progenitors in LTMC. Marrow stromal progenitors giving rise to stromal layers in LTMC, although less sensitive to 4-HC cytotoxicity, were damaged by 4-HC also in a dose-related manner. Marrows treated with 4-HC up to 300 mumol/L, gave rise to stromal layers composed of fibroblasts, endothelial cells, adipocytes, and macrophages. Cocultivation experiments with freshly isolated autologous hematopoietic cells showed that stromal layers derived from 4-HC- treated marrows were capable of sustaining the long-term production of CFU-GM as well as controls. In conclusion: (1) Hematopoietic progenitors cells, CFU-Mix, BFU-E, and CFU-GM, are highly sensitive to 4-HC, whereas marrow stromal progenitor cells are relatively resistant. (2) Marrows treated with 300 mumol/L 4-HC that are depleted of CFU-Mix, BFU-E, and CFU-GM can generate CFU-GM in LTMC, suggesting that most primitive hematopoietic stem cells (not represented by CFU-Mix) are spared by 4-HC up to this dose. (3) Consequently, the above colony assays are not suitable tools for predicting pluripotent stem cell survival after 4-HC treatment in vitro.  相似文献   
95.
An abnormal increase in numbers of CCGG sites methylated in the 5' region of the human calcitonin (CT) gene occurred in tumor cell DNA samples from 90% (17 of 19) of patients with non-Hodgkin's T and B cell lymphoid neoplasms and in 95% (21 of 22) of tumor cell DNA samples from patients with acute nonlymphocytic leukemia (ANLL). The changes were not seen in patients with chronic myelogenous leukemia (0 of 9). The abnormal methylation patterns appear to be a property only of transformed or malignant cells since they were not found in DNA from nonneoplastic adult tissues including sperm, early myeloid progenitor cells, benign lymphoid hyperplasia, peripheral lymphocytes stimulated to divide, or early myeloid progenitor cells (obtained by immunoaffinity using anti-My-10 antibody), but they did appear after Epstein-Barr virus transformation of lymphocytes. Moreover, during the course of therapy in patients with ANLL, the hypermethylation pattern reflects the presence of the leukemic clone even in normal-appearing granulocytes derived from this clone. The increased methylation of the CT gene may then provide an important molecular marker for biologic events in human cell transformation or tumor progression and may prove clinically useful in monitoring patients with lymphoid and acute myelogenous neoplasms.  相似文献   
96.
97.
Bower  M; Parry  P; Carter  M; Lillington  DM; Amess  J; Lister  TA; Evans  G; Young  BD 《Blood》1994,84(11):3776-3780
Rearrangements of the human trithorax gene (MLL, HRX, Htrx-1, All-1) were studied by Southern blotting in blast cells stored at presentation from 65 adults with de novo acute myelomonocytic (AML-M4) and acute monocytic leukemia (AML-M5). MLL rearrangements were demonstrated in 15 (23%) cases, including eight patients in whom karyotype analysis had failed to detect abnormalities of chromosome band 11q23. The patients with MLL rearrangements did not differ significantly from those with germline configurations in terms of the sex and age of the patients, the presence of lymphadenopathy, hepatosplenomegaly, or central nervous system involvement, and the absolute blast count at diagnosis. Kaplan- Meier analysis of the treated patients demonstrated no difference in survival for patients with MLL rearrangements compared with those without rearrangements. Therefore, in contrast to infantile acute leukemia, in adults with AML-M4 and AML-M5, MLL rearrangements do not identify a subgroup of patients with different clinical features or prognosis.  相似文献   
98.
99.
The prognostic significance of disease features recorded at the time of diagnosis was examined among 813 patients with Philadelphia chromosome- positive, nonblastic chronic granulocytic leukemia (CGL) collected from six European and American series. The survival pattern for this population was typical of "good-risk" patients, and median survival was 47 mo. There were multiple interrelationships among different disease features, which led to highly significant correlations with survival for some that had no primary prognostic significance, such as hematocrit. Multivariable regression analysis indicated that spleen size and the percentage of circulating blasts were the most important prognostic indicators. These features, and age, behaved as continuous variables with progressively unfavorable import at higher values. The platelet count did not influence survival significantly at values below 700 X 10(9)/liter but was increasingly unfavorable above this level. Basophils plus eosinophils over 15%, more than 5% marrow blasts, and karyotypic abnormalities in addition to the Ph1 were also significant unfavorable signs. The Cox model, generated with four variables representing percent blasts, spleen size, platelet count, and age, provided a useful representation of risk status in this population, with good fit between predicted and observed survival over more than a twofold survival range. A hazard function derived from half of the patient population successfully segregated the remainder into three groups with significantly different survival patterns. We conclude that it should be possible to identify a lower risk group of patients with a 2-yr survival of 90%, subsequent risk averaging somewhat less than 20%/yr and median survival of 5 yr, an intermediate group, and a high- risk group with a 2-yr survival of 65%, followed by a death rate of about 35%/yr and median survival of 2.5 yr.  相似文献   
100.
Koziner  B; Kempin  S; Passe  S; Gee  T; Good  RA; Clarkson  BD 《Blood》1980,56(5):815-823
Analysis of the morphological and immunologic [surface (Sm Ig) and cytoplasmic (Cy Ig) immunoglobulin, faintness (f.imfl) or brightness (b.imfl) of surface immunofluorescence, rosette formation with mouse erythrocytes (MR), or sheep red cells coated with C3 (EAC)] characteristics of the neoplastic lymphocytes involved in 137 cases of B-cell leukemias allowed the differentiation of the following cytologic categories: B1 small lymphocytes (71); SM Ig+, f.imfl., Cy Ig-, MR+, EAC+; B2 prolymphocyte (4): SM Ig+, b.imfl., Cy Ig-, MR+, EAC+. B3 plasmacytoid lymphocyte (2): Sm Ig+, b.imfl., Cy Ig+/-, MR+!-, EAC+/- B4 small cleaved lymphocyte (23): Sm Ig+, b.imfl., Cy Ig-, MR-, EAC+. B5a large cleaved and B5b noncleaved lymphocytes (14): Sm Ig+, b.imfl., Cy Ig-, MR-, EAC-. B6 small noncleaved "Burkitt-like" lymphocyte (5): Sm Ig+, b.imfl., Cy Ig-, MR-, EAC-. B7 plasma cell (2): Sm Ig+, MR-, EAC-. B8 hairy cell (16): Sm Ig+, b.imfl., Cy Ig-, MR-, EAC-, also exhibiting ingestion or attachment of particulate material, not seen in other types. Improved delineation of the heterogeneous group of B-cell leukemias might be of developmental significance in lymphocyte differentiation and improve current prognostic and therapeutic criteria.  相似文献   
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