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21.
目的 探讨血液肿瘤患者肛拭子耐碳青霉烯类肠杆菌(CRE)主动筛查情况及继发血流感染的影响因素。方法 选取2020年9月—2022年6月在苏州大学附属第一医院治疗的血液肿瘤患者1 258例,所有患者行肛拭子CRE主动筛查,分析CRE定植分布、血流感染情况及其影响因素。结果 共检出CRE 109株,以肺炎克雷伯菌、大肠埃希菌为主;10例患者发生CRE血流感染;CRE酶型分布中,主要以NDM、KPC为主;有中性粒细胞缺乏患者CRE定植发生率高于无中性粒细胞缺乏患者(P<0.05);有消化道症状患者CRE定植发生率高于无消化道症状患者(P<0.05);多因素逐步Logistic回归分析结果显示,中性粒细胞缺乏■是血液肿瘤患者CRE定植发生的影响因素(P<0.05)。不同性别、年龄、疾病类型及有无中性粒细胞缺乏、消化道症状患者的血流感染发生率比较,差异均无统计学意义(P>0.05)。结论 血液肿瘤患者肛拭子CRE主动筛查能有效筛出CRE感染者,CRE定植感染与中性粒细胞缺乏有关,临床应加以重视。  相似文献   
22.
To elucidate the role of vascular endothelial growth factor (VEGF), an endothelial cell-specific mitogen, in tumour angiogenesis and malignant progression, an expression vector harboring human VEGF cDNA was stably transfected into three human cancer cell lines with poor VEGF productivity. Though their in vitro growth rate and intrinsic productivity of another angiogenic factor, basic fibroblast growth factor (bFGF), were not changed by transfection, those clones with higher VEGF production were endowed with tumorigenic and angiogenic potentials as follows: firstly, nontumorigenic, lung carcinoma QG90 cells having lower bFGF productivity acquired tumorigenicity as well as significant in vivo angiogenesis-inducing ability, secondly, tumorigenic colorectal carcinoma RPMI4788 cells having higher potency for bFGF production could form more vascularized solid tumour with faster growth rate and thirdly, oestrogen-dependent breast carcinoma MCF-7 cells, which did not produce detectable bFGF, acquired tumorigenicity even in the absence of oestrogen and the solid tumour growth rate was remarkably enhanced, accompanied with increased vascularization, in the presence of oestrogen. These results suggest that tumour progression closely depends on angiogenesis, and VEGF significantly contributes to malignant progression of a variety of tumour cells through its potent angiogenic activity, independent on the bFGF productivity of tumour cells.  相似文献   
23.
Children with malignancy are immunosup-pressed and susceptible to serious infections with herpesviruses. The majority of children on chemotherapy for malignancy are seropositive for human herpesvirus-6 (HHV-6), and although HHV-6 has been demonstrated to be a pathogen in severely immunocompromised patients, whether this is the case for paediatric oncology patients is unknown. HHV-6 is secreted in saliva and in this study samples were examined prospectively for HHV-6 DNA in healthy children and those with malignancy. In a nested polymerase chain reaction (PCR), a 287 bp outer fragment and 163 inner fragment of HHV-6 DNA were amplified. The resulting amplimer contained a Hind III restriction site present only in “B” type HHV-6 and this was used to identify the type of HHV-6 amplified. In saliva from healthy control children, 74% (28/38) of samples were HHV-6 DNA-positive in either the supernate, pellet or both. In the patients, 58% (45/77) of all samples were HHV-6 DNA-positive. When sequential samples from twelve patients were examined the children appeared to fall into two groups: those who were frequently HHV-6 DNA-positive (60% of samples or more) and those who were rarely HHV-6 DNA-positive (33% of samples or less) (P < 0.0001). The only apparent difference between these two groups was that the less frequently HHV-6-positive group was more often febrile and unwell with neutro-paenia. Hind III digestion demonstrated all the positive samples to be “6” type HHV-6. Possible explanations for this difference in HHV-6 secretion between the patient groups are discussed. © Wiley-Liss, Inc.  相似文献   
24.
一种新型免疫细胞—NKT细胞   总被引:1,自引:0,他引:1  
NKT细胞(natural killer T cells)是一类表达NK细胞表面分不志的α/βT淋巴细胞,具有迅速分泌大量细胞因子的能力,能够对效应细胞提供早期的辅助以及在一些免疫反应中调控TH1和TH2辅助细胞的分化,NKT细胞识别由CD1d分子提呈的抗原,其作用机理既不同于NK细胞也不同于T,B淋巴细胞,在一些自身免疫性疾病,肿瘤监视及抗肿瘤方面有着非常重要的作用。  相似文献   
25.
The purpose of this study was to investigate tumor angiogenesis in a series of benign and malignant pheochromocytomas and to determine whether there is a correlation between angiogenesis and the presence of distant metastases. In this study, the CD31 monoclonal antibody was selected to measure intratumoral microvessel density. Nineteen patients with malignant pheochromocytomas and nineteen patients with benign pheochromocytomas who underwent operation were studied. In order to quantify intratumoral microvessel density, the total number of pixels of CD31-positive reactivity was assessed and expressed as a percentage of the total tissue area in the analyzed field. Analysis of variance revealed a statistically significant correlation between malignancy and intratumoral microvessel density (p=0.0009). Although there was a considerable variability in the intratumoral microvessel density from tumor to tumor within both the benign and the malignant group, a percentage of more than 28.5% anti-CD31 stained area was found only in malignant tumors. In conclusion, this study shows that the mean intratumoral microvessel density in malignant pheochromocytomas is increased approximately two-fold as compared with benign tumors. However, the clinical significance of this prognostic marker is rather weak, because only 4 of the 19 malignant pheochromocytomas had microvesel density higher than this threshold of 28.5%.  相似文献   
26.
Dendritic cells (DC) are a group of potent antigen-presenting cells (APC) specialized for initiating T cell immune responses. They originate from the bone marrow and upon stimulation with bacterial products, cytokines or CD40 ligation they acquire the ability to migrate to the secondary lymphoid organs. In vitro DC can be generated from human CD34(+) bone marrow cells and CD14(+) peripheral blood monocytes after culture with different cytokine combinations. Since most leukemic cells and tumors in general are devoid of APC capacities, various strategies have been used to increase their recognition and confer the capacity of antigen presentation on them. Because of our interest in the design of vaccine immunotherapy protocols for the adjuvant treatment of patients with lymphoid malignancies (LM), we chose to explore the capacity of human acute lymphoblastic leukemia, chronic lymphocytic leukemia and plasma cell leukemia to differentiate into cells with APC and DC features. Our results among a sample of 10 patients demonstrate that such approach is feasible. Leukemic cells could be induced in the presence of IL-4 and CD40L to exhibit a DC morphology with a phenotype of mature DC-like cells. They could also induce a potent proliferative response in naive CD4(+) T cells. In addition, they expressed chemokine receptor CCR7 and CD62L, and could drive T cells towards a T(h)1 response with secretion of IFN-gamma. Our strategy leading to increased LM cell immunogenicity may have potential clinical applications and LM appear to be attracting candidates for adjuvant vaccination and adoptive immunotherapy.  相似文献   
27.
The aim of this study was to describe the distributions of superficial malignant neoplasms diagnosed by fine-needle aspiration cytology (FNAC). A prospective cross-sectional study was conducted within the Jimma Teaching Hospital, Pathology Department, Jimma University during the years between September 1998 and August 2002. Cases fulfilling cytopathological evidences of superficial malignancies were included whereas deep-seated malignancies were excluded from the study. An air-dried smear stained with the Wright staining procedure was utilized for the FNAC diagnostic technique. A total of 3,200 cases were investigated during the study period where 267 (8.3%) cases were of primary superficial malignant neoplasms, with 98 cases in the peak age group of 40-59 yr (36.7%) and a median age of 38.0 yr (range, 0.2-88 yr). The most frequent superficial cytodiagnosis was breast carcinoma, 79 (29.6%) cases; followed by non-Hodgkin's lymphomas, 37 (13.9%) cases; and soft tissue sarcomas, 26 (9.7%) cases. The overall male-to-female ratio showed preponderance to female patients (1:1.3). Carcinomas were identified more frequently in those >40 yr of age whereas sarcomas were identified in those <40 yr of age (P > 0.05). The most common malignant neoplasm in women was breast carcinomas found in 74 (27.7%) cases, whereas in men non-Hodgkin's lymphomas were found in 29 (10.9%) cases. Large proportions of carcinomas (88 cases, 33.0%), lymphomas (33 cases, 12.4%), and sarcomas (20 cases, 7.5%) were detected on the trunk, head, and neck, as well as on the lower limb regions, respectively. This study uncovered different types of superficial malignant neoplasms that are prevalent in the southwestern part of Ethiopia. The most common types of cytodiagnoses such as breast carcinomas, etc. may suggest that attention be given to future high-caliber prospective studies in trying to identify some of the associated strong risk factors for the disease under study. This study may be helpful to local health planners in prioritizing some of the commonest malignancies. Some of the diagnostic challenges of lymphomas and thyroid follicular lesions were shown also. This investigation is the first in Ethiopia and therefore may act as baseline data for similar studies in the future.  相似文献   
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29.
Summary In patients with malignant tumors a high incidence of haemostatic disorders occurs. The reaction of thrombin with its major inhibitor antithrombin III (AT III) leads to the formation of a stable complex, which represents a sensitive marker for the activation of intravascular coagulation. In 153 patients suffering from different kinds of gynaecological malignancy thrombin-antithrombin III-complex (TAT) levels were measured. In 21 cases the course of the disease was studied. Of 153 patients with gynaecological malignancy 102 (67%) showed TAT plasma concentrations above the normal range before therapy. Seven patients with elevated TAT levels before treatment showed a decrease of TAT concentrations to the normal range when no evidence of disease was obvious. In 5 cases TAT levels were in the normal range before and after successful therapy. 4 patients with tumor progression and 5 patients with tumor recurrence showed an increase of TAT levels. The TAT plasma concentrations correlated with the presence or absence of the tumor. Measurement of TAT plasma concentrations in gynaecologic malignancies can detect any thromboembolic risk for the patient and in addition can reveal information about the course of the disease.Abbreviations Thrombin-Antithrombin III Komplex (TAT) - Antithrombin III (AT III)  相似文献   
30.
本文旨在探讨盆腔恶性肿瘤的介入性治疗问题。对45例患有盆腔恶性肿瘤的患者,采用Seldinger法,经双侧股动脉插管,先端选择性导入对侧髂内动脉;或一侧导入肠系膜下动脉,另侧导入髂内动脉,留置导管12小时,使用突击剂量持续灌注化疗药物。并经手术、B超、CT、内窥镜及指检等方法进行化疗前后的对比观察。结果:其中病灶消失持续1个月以上者9例、病灶缩小50%以上并持续超过一个月者23例、缩小不足50%且增大未达25%者9例、增大超过25%以上者4例,总有效率为71.1%。10例患者出现了脱发及皮肤色素沉着,1例患者出现下肢动脉栓塞,10例出现了不同程度的消化道反应等。结论:本法损伤小,操作简便安全,可多次重复术式:选择性强,药效持久均衡且毒副作用小;可提高手术切除率,也为不能手术的癌肿提供一种较理想的治疗手段。  相似文献   
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