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101.
Sixteen patients with suspected cerebral metastases were studied with magnetic resonance (MR) imaging before and after the intravenous administration of 0.1 mmol/kg of gadolinium diethylenetriaminepenta-acetic acid. The images were interpreted blindly by two neuroradiologists; all clinical, radiologic (computed tomographic and MR imaging), and pathologic data were reviewed to arrive at a final "best diagnosis," which was then compared with the prior blinded interpretations. Of seven patients found to have multiple metastases, six (86%) had at least one tumor nodule depicted by postinfusion MR imaging that was missed by one or both observers on review of preinfusion images alone. Lesions missed on preinfusion studies were usually small nodules hidden by or not detected next to regions of high-signal edema thought to be related to the adjacent tumor nodule. The authors believe that contrast enhancement improves detection of metastatic foci with MR imaging and that the findings indicate broader implications for the detection of multiple lesions from other causes.  相似文献   
102.
目的研究MR氢质子波谱(^1H-MRS)成像在神经上皮组织肿瘤分级中的价值。方法52例颅内神经上皮组织肿瘤患者,低级别29例,高级别23例,均行MRI及^1H-MRS检查。结果52例中,Ⅱ级9例,Ⅲ级11例,Ⅳ级12例,将Ⅱ级列为低级别组,Ⅲ级、Ⅳ级为高级别组,脂质(Lip)[乳酸(Lac)]/肌酸(Cr)、Lip(Lac)/N-乙酰天门冬氨酸(NAA)、Lip(Lac)/胆碱化合物(Cho),Lip(Lac)在组间差异有统计学意义,低级别组各代谢物比值中位数分别为0.14、0.16、0.09、0.32,高级别组各代谢物中位数分别为1.64、1.24、0.87、1.68。Lip(Lac)/Cr≤0.425为低级别肿瘤,Lip(1ac)/Cr>0.425为高级别肿瘤,诊断敏感度、特异度、阳性予测值、阴性预测值分别为87.0%、96.6%、95.2%、90.3%。常规MR图像诊断肿瘤级别敏感度、特异度、阳性予测值、阴性预测值分别为87.0%、82.8%、80.0%、88.9%。结论^1H-MRS在神经上皮组织肿瘤分级中有一定的价值,常规MR图像结合MRS可明显提高诊断准确率。  相似文献   
103.
104.
目的:检测急性非淋巴细胞白血病患者白血病细胞表面MHC—Ⅱ类分子和共刺激分子的表达情况。方法:采集骨髓中白血病细胞大于70%的27例初诊或复发息者骨髓细胞。荧光抗体标记。应用流式细胞仪进行HLA—DR、CD80(B7-1)和CI)和(B7—2)免疫标记检测。结果:27例病人除M3型表达明显低于其他各型外。HLA—DR抗原的表达均较高。其中M2型最高为90%;CD80阳性率很低,最高为M1型只有5%。其余均在l%~3%之间。CD86的表达高于CD80,最高为M5型为48%,最低为M6型为11%。结论:白血病细胞表面共刺激分子表达以CD80缺乏为主。  相似文献   
105.
Nyberg  DA; Filly  RA; Filho  DL; Laing  FC; Mahony  BS 《Radiology》1986,158(2):393-396
Simultaneous sonography and quantitative serum human chorionic gonadotropin (HCG) levels from 126 women with threatened abortion were compared. Of 56 women with normal outcome, 39 (70%) had a gestation sac greater than or equal to 5 mm in mean sac diameter, and in each case the HCG level was 1,800 milli-international units (mIU/ml) or greater. The serum HCG levels strongly correlated with the gestation sac sizes to a mean sac diameter of 25 mm. Of 70 abnormal pregnancies, 31 demonstrated a gestation sac. Of these, 20 women (65%) had disproportionately low HCG levels relative to sac size, including 12 in whom the HCG level was less than 1,800 mIU/ml. One woman with an early molar pregnancy had a disproportionately elevated HCG level. Correlation of sonograms with a simultaneous measurement of serum HCG level is a useful method for evaluating threatened spontaneous abortion. A disproportionately low HCG level relative to gestation sac size is evidence for an abnormal pregnancy.  相似文献   
106.
Clark  DA; Dessypris  EN; Jenkins  DE Jr; Krantz  SB 《Blood》1984,64(5):1000-1005
We have investigated the hemolytic mechanisms in a patient with acquired immune hemolytic anemia whose red cells appeared to be coated with IgA alone. The clinical course was similar to that of patients with hemolytic anemia mediated by warm-reacting IgG antibody. Splenic sequestration of red cells was demonstrated, and marked reduction of hemolysis occurred after corticosteroid therapy. Antibody was eluted from the patient's red cells and used to sensitize normal red cells in vitro. These sensitized red cells were not lysed by fresh autologous serum, nor did they fix detectable amounts of C3. However, red cells sensitized by eluted antibody were lysed by normal human peripheral blood monocytes in a system designed to demonstrate antibody-dependent cell-mediated cytotoxicity. Monocyte-mediated hemolysis of sensitized red cells was inhibited by the addition of low concentrations of normal serum IgA to the system, but not by IgG. The ability of the eluate to induce monocyte-mediated hemolysis was abolished by its adsorption on Sepharose-bound anti-IgA, but not by preincubation with Sepharose-bound anti-IgG. In addition, normal human monocytes were demonstrated to ingest eluate-sensitized red cells. These data demonstrate an in vitro interaction of IgA-sensitized red cells with leukocytes and suggest a possible mechanism for the patient's hemolysis.  相似文献   
107.
目的 探讨Lafora病的临床、病理特点及诊断方法.方法 总结分析5例经腋窝皮肤活体组织检查确诊的Lafora病患者的临床和组织病理学特点.5例患者都进行了腋窝皮肤活体组织检查,常规行HE、糖原(PAS)和阿辛蓝-糖原(AB-PAS)染色.结果 5例患者中4例青少年发病,1例成年起病.所有患者均表现为进行性加重的强直阵挛发作、肌阵挛和智能损害,可早期出现性格改变,构音障碍和行走不稳.腋窝皮肤活体组织检查发现Lafora包涵体存在于大、小汗腺的肌上皮细胞和导管细胞内.结论 经皮肤活体组织检查发现PAS阳性圆形或卵圆形包涵体,结合Lafora病典型的临床表现可以确诊该病;皮肤活体组织检查的部位可选择腋窝或腋窝以外的部位.  相似文献   
108.
109.
Between 1978 and 1981, 74 women with nonpalpable breast cancer underwent surgery after localization guides were placed. In 72 patients, guides were introduced parallel to the chest wall; in two the needle was positioned anteroposteriorly under computed tomographic guidance. Fifty-six cases (76%) were infiltrating cancer; 13 (17%), intraductal cancers; two (3%), inflammatory; and three (4%), lobular carcinoma in situ. Surgery was not used to treat the latter five patients. In the remaining 69 women, 42 (61%) were treated by means of modified radical mastectomy; six (9%), total mastectomy; 12 (17%), local excision and radiation therapy; and seven (10%), local excision alone; exact therapy for two women (3%) was unknown. At a minimum follow-up of 5 years, none of the 67 women in whom the parallel approach was used had a local recurrence. The authors conclude that preoperative placement of guides parallel to the chest wall does not appear to increase the risk of local breast cancer recurrence.  相似文献   
110.
Lynch  DA; Gamsu  G; Ray  CS; Aberle  DR 《Radiology》1988,169(3):603-607
In 260 asbestos-exposed individuals evaluated by means of computed tomography (CT), 43 unsuspected pulmonary masses were found in 27 individuals. The masses included fissural pleural plaques (n = 10), dense fibrotic bands (n = 3), round atelectasis (n = 11), carcinomas (n = 3), and other presumed benign masses (n = 16). The most helpful features in the diagnosis of rounded atelectasis with CT were (a) contiguity to areas of diffuse pleural thickening, (b) a lentiform or wedge-shaped outline, (c) evidence of volume loss in the adjacent lung, and (d) a characteristic "comet tail" of vessels and bronchi sweeping into the margins of the mass. Less advanced areas of focal atelectasis had fewer classic features. Intrafissural pleural plaques were readily identified with high-resolution CT. In asbestos-related masses, the demonstration of stability over time is necessary. Careful interpretation of CT and high-resolution CT features and close surveillance can obviate the need for biopsy in the majority of instances.  相似文献   
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