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391.
Fifteen patients with lymphoma and hypercalcemia (greater than or equal to 11.0 mg/dL) were identified by screening the serum chemistry profile obtained from patients upon admission to the Los Angeles County/USC Medical Center. Seven of the 15 (47%) possessed a frankly elevated serum concentration of 1,25-dihydroxyvitamin D [1,25-(OH)2-D]. An additional patient with severe hypercalcemia (16.2 mg/dL) had a serum 1,25-(OH)2-D concentration in the midnormal range, not a suppressed value. To examine the potential existence of hypercalciuria in absence of overt hypercalcemia, prospective screening of 23 normocalcemic patients with lymphoma was undertaken. Four of the 23 patients (17%) had increased fractional urinary calcium excretion rates (0.35 +/- 0.3 mg calcium/100 mL glomerular filtrate [GF], mean +/- SE; normal, less than 0.16 mg/100 mL GF); two of the hypercalciuric patients had a frankly elevated serum 1,25-(OH)2-D concentration. Of the 19 hypercalcemic/hypercalciuric lymphoma patients identified, none had an elevated serum immunoreactive parathyroid hormone concentration. Fourteen of the 19 hypercalcemic/hypercalciuric patients (74%) suffered from B-cell neoplasms, three had Hodgkin's lymphoma, and two had adult T-cell leukemia/lymphoma. All hypercalcemic/hypercalciuric patients had widespread disease (stage III or IV). Six patients, four with hypercalcemia and two with hypercalciuria, had acquired immunodeficiency syndrome (AIDS). These data suggest that the deregulated synthesis of a 1,25-(OH)2-D-like metabolite is a common cause of hypercalcemia and hypercalciuria in patients with lymphoma including patients with AIDS-associated tumors. 相似文献
392.
崔杰峰 《中华检验医学杂志》2000,23(5):310-310
过去 5年中 ,在人类基因组测序和确定有临床意义的基因方面取得了巨大进展。具有临床意义的基因在疾病的诊断和预后估计以及疾病治疗中具有重要价值。通过直接测序将首先确定由种系和体细胞DNA改变引起的未知基因突变 ,随后应用其他一些检测特别突变的方法。最近出现了采用PCR和荧光杂交探针相结合的均一扩增技术用于基因型测定的设备和方法 ,并可在 1h内完成产物分析。基因DNA通过快速循环PCR扩增 ,在反应开始时加入全部所需的试剂 ,15~ 2 0min后完成PCR ,仪器自动描记出一个熔解曲线。随着反应逐渐加热 ,进行连续荧光… 相似文献
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395.
Enzyme histochemistry and immunohistochemistry on biopsy specimens of pathologic human bone marrow 总被引:14,自引:0,他引:14
We have systematically investigated a variety of fixation and plastic embedding procedures and arrived at a method that allows processing of approximately 2-micron sections of bone marrow biopsies for examination by light microscopy. More importantly, this method permits the use of enzyme histochemical and immunohistochemical procedures that are rapidly becoming mandatory in the diagnosis of hematologic malignancies. Over 200 full-length bone marrow biopsy specimens were fixed in a mixture of paraformaldehyde, glutaraldehyde, and acrolein, dehydrated in acetone, and embedded in a mixture of methyl and glycolmethacrylate. All procedures were carried out at 4 degrees C. Decalcification was unnecessary. Sections 2-micron thick were cut and incubated for peroxidase, naphthol AS-D chloroacetate esterase, alpha- naphthyl butyrate esterase, acid phosphatase (with and without tartrate), or alkaline phosphatase and then examined by light microscopy. Specimens could be prepared for examination within 48 hr. This approach, which provides definitive markers for various hematopoietic cell lines in intact tissues, is invaluable when aspirated material is unavailable. It is also useful in the analysis of focal lesions of bone marrow due to inflammation or neoplasia and shows potential as an investigative tool. For example, we have discovered that early myelofibrosis is accompanied by a marked increase in the number of alkaline-phosphatase-positive reticulum cells. 相似文献
396.
青藏高原东部地区发现的新种: 石渠棘球绦虫的生物学特征 总被引:1,自引:0,他引:1
青藏高原东部是细粒棘球绦虫和多房棘球绦虫的混合流行区,诸多的家畜和野生动物参与了棘球绦虫的传播。近年来,一种未知的棘球绦虫先后从高原鼠兔(Ochotona curzoniae)和藏狐(Vulpes ferrilata)中被分离出来。由于其特有的形态学、分子遗传学、寄生宿主和地理分布特征,而被作为新种 ——— 石渠棘球绦虫(Echinococcus shiquicus,Xiao et al,2005)进行了系统研究。本文对该虫种的生物遗传学和流行病学特征进行了讨论,并提出了理论上的假设来解释一些仍不十分清楚的现象。 相似文献
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398.
P S Roheim M Carey T Forte G L Vega 《Proceedings of the National Academy of Sciences of the United States of America》1979,76(9):4646-4649
The presence of apolipoproteins A-I, E, C-II, and C-III and the absence of apolipoprotein B was demonstrated in human cerebrospinal fluid. The concentration of apolipoproteins was measured by electroimmunoassay. Apolipoproteins E, C-II, and C-III were present in cerebrospinal fluid at 3--5% of their concentration in plasma; the cerebrospinal fluid level of apolipoprotein A-I was 0.4%. Most of the cerebrospinal fluid apolipoproteins were present in the rho less than 1.21 g/ml lipoprotein fraction. The major apolipoporteins of cerebrospinal fluid are E and A-I. The possible mechanism of transfer and the physiological and pathophysiological role of apolipoproteins in cerebrospinal fluid are postulated. 相似文献
399.
400.
PS Teirstein V Massullo S Jani RJ Russo DA Cloutier RA Schatz EM Guarneri S Steuterman K Sirkin S Norman P Tripuraneni 《Circulation》1999,99(2):243-247
BACKGROUND: Although early trials indicate the treatment of restenosis with radiation therapy is safe and effective, the long-term impact of this new technology has been questioned. The possibility of late untoward consequences, such as aneurysm formation, perforation, and accelerated vascular disease, is of significant concern. Furthermore, it is not known whether the beneficial effects of radiation therapy will be durable or whether radiation will only delay restenosis. METHODS AND RESULTS: A double-blind, randomized trial was undertaken to compare 192Ir with placebo sources in patients with previous restenosis after coronary angioplasty. Patients were randomly assigned to receive a 0.76-mm (0. 03-in) ribbon containing sealed sources of either 192Ir or placebo. All patients underwent repeat coronary angiography at 6 months. All living patients were contacted 24 months after their index study procedure. Patients were assessed with respect to the need for target-lesion revascularization or nontarget-lesion revascularization, occurrence of myocardial infarction, or death. Over a 9-month period, 55 patients were enrolled; 26 were randomized to 192Ir and 29 to placebo. Follow-up was obtained in 100% of living patients at a minimum of 24 months. Target-lesion revascularization was significantly lower in the 192Ir group (15.4% versus 44.8%; P<0. 01). Nontarget-lesion revascularization was similar in 192Ir and placebo patients (19.2% versus 20.7%; P=NS). There were 2 deaths in each group. The composite end point of death, myocardial infarction, or target-lesion revascularization was significantly lower in 192Ir-treated versus placebo-treated patients (23.1% versus 51.7%; P=0.03). No patient in the 192Ir group sustained a target-lesion revascularization later than 10 months. CONCLUSIONS: At 2-year clinical follow-up, treatment with 192Ir demonstrates significant clinical benefit. Although further follow-up (including late angiography) will be necessary, no clinical events have occurred to date in the 192Ir group to suggest major untoward effects of vascular radiotherapy. At the intermediate follow-up time point, vascular radiotherapy continues to be a promising new treatment for restenosis. 相似文献