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11.
Eight laboratories in six countries cooperated to clarify several issues concerning the phenotypes of heterozygous carriers of hemophilia "A." Plasma levels of factor VIII (F.VIII:C, formerly VIII:C) and von Willebrand factor (VWF:Ag, formerly VIIIR:Ag) of carriers and normal women were determined by various "in-house" methods; a single lyophilized plasma standard was used for all assays. Analysis of the collated data from 336 carriers (296 obligatory carriers and 40 sporadic carriers) and 137 normal women showed that there was no difference in the F.VIII:C levels of "paternal" carriers (women who had obtained the abnormal gene from their fathers) and "maternal" carriers. Neither was there a difference in the VWF:Ag levels of normal women and either type of carrier. Age was found to have a significant effect on both F.VIII:C and VWF:Ag, values being higher at very young and very old ages, the minima occurring in the 25- to 30-year range. ABO blood type had a striking effect. Women of types A, B, and AB (designated non- O in the study), both normals and carriers, had significantly higher levels of both factors than did women of type O. Analysis by laboratories showed that differences in mean levels of both factors between laboratories were highly significant. It was concluded that age, ABO blood type, and laboratory variation should be taken into account in carrier detection.  相似文献   
12.
Insulin receptors on leukemia and lymphoma cells   总被引:1,自引:0,他引:1  
Chen  PM; Kwan  SH; Hwang  TS; Chiang  BN; Chou  CK 《Blood》1983,62(2):251-255
Tumor cells obtained from leukemia and lymphoma patients were investigated for specific insulin receptors. Using radioactive 125I- labeled insulin, specific insulin binding sites were demonstrated on most acute lymphocytic leukemia (ALL) and acute myelocytic leukemia (AML) cells, including acute promyelocytic leukemia (APL), chronic myelocytic leukemia (CML), and acute monocytic leukemia (AMoL) cells. Insulin receptors were not found on chronic lymphocytic leukemia (CLL) and malignant lymphoma (ML) cells. Specific insulin binding sites were also found on monocytes and thymocytes after treatment with phytohemagglutinin (PHA-P), but not on inactivated tonsil cells, peripheral blood lymphocytes, or thymocytes. There was no inverse correlation between the content of insulin receptors and the basal level of circulating insulin. These data suggest that the insulin receptor may be a new marker of acute leukemia and chronic myelocytic leukemia.  相似文献   
13.
Breast cancer is the most common cause of cancer death in women in this country. Until recently, the traditional treatment has been radical surgery with or without radiation therapy for patients with primary breast cancer, and palliative endocrine therapy followed by chemotherapy for patients with advanced disease. These treatments have met with limited effectiveness in terms of eradicating the disease. Studies in the past decade have given cause for optimism for breast cancer patients. Adjuvant systemic therapy after local treatment appears promising for certain subsets of patients with primary breast cancer. The development of estrogen receptor assays has markedly changed our approach to the disease and improved patient care. Estrogen receptor is an important prognostic factor and is useful in planning appropriate therapy for patients with primary breast cancer as well as those with advanced disease. Further research is urgently needed to improve the dismal survival of certain women with this common malignancy.  相似文献   
14.
Human T-cell lymphotropic virus I (HTLV-I)-induced adult T-cell leukemia (ATL) cells constitutively express interleukin-2 (IL-2) receptors identified by the anti-Tac monoclonal antibody (MoAb), whereas normal resting cells do not. This observation provided the scientific basis for a trial of intravenous anti-Tac in the treatment of nine patients with ATL. The patients did not suffer untoward reactions and did not have a reduction in the normal formed elements of the blood, and only one of the nine produced antibodies to the anti-Tac MoAb. Three patients had transient mixed, partial, or complete remissions lasting from 1 to more than 8 months after anti-Tac therapy, as assessed by routine hematologic tests, immunofluorescence analysis of circulating cells, and molecular genetic analysis of HTLV-I provirus integration and of the T-cell receptor gene rearrangement. The precise mechanism of the antitumor effects is unclear; however, the use of a MoAb that prevents the interaction of IL-2 with its receptor on ATL cells provides a rational approach for the treatment of this malignancy.  相似文献   
15.
二十碳五烯酸对三种肝癌细胞系作用的实验研究   总被引:2,自引:0,他引:2  
目的 探讨二十碳五烯酸(eicosapentaenoic acid,EPA)对3种肝癌细胞系作用。方法 EPA作用于HepG2(携带有野生型p53基因)、Huh7(携带有突变型p53基因)和Hep3B(p53基因缺失)这3种肝癌细胞系,通过细胞计数、DNA电泳、流式细胞技术和末端转移酶标记技术等来检测EPA对这3种细胞系的作用和可能的机制。结果 EPA主要是通过诱导HepG2肝癌细胞系的细胞凋亡来抑制其生长,而且这种抑制作用呈现出时间和剂量依赖的关系。而且同时发现EPA对于Huh7和Hep3B这两种肝癌细胞系无明显抑制作用。结论 细胞凋亡的诱导可能是EPA抑制HepG2肝癌细胞系生长的主要机制。而且p53基因可能参与EPA诱导HepG2细胞系细胞凋亡的过程。  相似文献   
16.
Background: Optomap uses the ultra‐wide field scanning laser ophthalmoscopy to provide retinal examination. It permits fundus examination without the use of a mydriatic, which is more comfortable for the patients. This paper determines the sensitivity and specificity of the Optomap for detecting retinal signs under non‐mydriatic conditions. Methods: Fifty‐four eyes identified with retinal/choroidal signs and eight normal eyes were recruited from 31 Hong Kong Chinese subjects. Photo‐documentation of fundal changes was obtained with the Optomap under non‐mydriatic conditions before a dilated fundus examination by a clinician using standard procedures. The eyelid was retracted using a cotton bud when necessary. Dilated fundus examinations were performed by another clinician using binocular indirect ophthalmoscopy and slitlamp biomicroscopy with a fundus lens. The Optomap images were evaluated by four other investigators under masked condition. The International Classification of Disease, Ninth Revision (ICD‐9‐CM) was adopted for recording retinal features. Screening results were compared with those obtained using the dilated fundus examination as the gold standard. Results: The cotton bud method for eyelid retraction showed an improvement in the area of retina that could be visualised. The sensitivity and specificity of the Optomap averaged 76.4 and 71.9 per cent, respectively. Some fundal signs were missed by all observers in the Optomap but not with the biomicroscope. These included white‐without‐pressure, lattice degeneration, paramacular drusen and pigmentary changes at central fundus. Conclusion: Optomap serves as a reliable screening tool for fundus examination especially because it covers a much wider area of the peripheral retina than other digital instruments for fundus photography.  相似文献   
17.
中国流行性乙型脑炎防制策略   总被引:7,自引:0,他引:7  
流行性乙型脑炎(简称乙脑)是由携带乙脑病毒的蚊子叮咬人体引起的急性中枢神经系统传染病,是一种人畜共患的自然疫源性疾病.临床以高热、嗜睡、惊厥、昏迷、抽搐为主要表现,严重者可致死亡,部分病例可留有后遗症.近年来,我国每年的乙脑病例数波动于5000例~8000例之间,在法定传染病排序中位于前10位以外,其死亡数和病死率分别排在第2位~6位和第4位~8位,在我国局部地区时有暴发,依旧是严重威胁儿童健康的主要传染病之一.本文在对我国乙脑防治工作现况、存在的问题进行分析的基础上,提出了相应的防制策略.……  相似文献   
18.
19.

OBJECTIVE:

To ascertain the variation in asthma management practices among paediatricians and family physicians to determine how to improve care.

DESIGN:

Questionnaire study of paediatricians and family physicians that focused on the use of beta2-agonists, inhaled corticosteroids, patient asthma education, quantitative measurements of airflow and diagnostic investigations for asthma. Case scenarios were used in the questionnaire.

RESULTS:

The response rate was 66% (415 of 632) among paediatricians and 42% (1156 of 2750) among family physicians. In general, both groups followed consensus guidelines. There were some differences in management practices among paediatricians and family physicians. Paediatricians were more likely to develop an action plan and less likely to use xanthines or inhaled anticholinergic agents. However, family physicians were more likely to use spirometry or home peak expiratory flow rates to make a diagnosis of asthma.

CONCLUSION:

Family physicians and paediatricians require a different focus on educational interventions to improve the care of children with asthma.  相似文献   
20.
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