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101.
闫实  曲迅  韩金祥 《医学综述》2006,12(7):385-387
骨形态发生蛋白(BMPs)属于转化生长因子-β超家族,其在骨的再生和修复中起重要作用。许多的研究还发现BMP参与调节许多种细胞的增殖、分化和凋亡的生物学过程,本文就其生物学特征、作用方式及BMP-2与肿瘤发生关系的作用简要综述。  相似文献   
102.
目的研究放射性125I粒子源治疗前列腺癌的剂量分布。方法采用三维治疗计划系统(3-DTPS)进行实验模拟,前列腺癌用肿瘤模型代替,应用热释光剂量学方法,模拟测量前列腺癌中的剂量分布。结果实验表明,125I粒子源治疗前列腺癌是在不均匀剂量模式下受照,剂量直接与粒子源的数量和几何位置有关。结论125I粒子源表面剂量最高,随着距离增加而剂量迅速下降。粒子源的间距越小瘤内剂量越高。  相似文献   
103.
Breast cancer is one of the most frequently diagnosed cancers among women in the western world. Due to the aggressive behaviour of some specific types and the possibility of an early diagnosis, breast cancer has been constantly studied. Tumour size, histological type, cellular and nuclear characteristics, mitotic index, vascular invasion, hormonal receptors and axillary lymph node status are biomarkers routinely used. However, these parameters are not enough to predict the course of this disease. Molecular biology advances have made it possible to find new markers, which have already been incorporated to the clinical practice. Their ultimate goal is to reduce mortality by identifying women at risk for the development of this disease, help diagnosis, determine prognosis, detect recurrences, monitor and guide treatment, and in particular cancers they are suited for general screening. Tumour markers in breast cancer were ranked in categories reflecting their clinical utility, according to the American College of Pathologists. This article focuses on traditional and new molecular markers stratifying them into categories and emphasizing their relevance in the routine evaluation of patients with breast cancer.  相似文献   
104.
Purpose This study was conducted to investigate a case of reactive lymphoid hyperplasia following laser assisted in situ keratomileusis (LASIK). Methods A 31-year-old man who underwent LASIK presented 1 month later with a fleshy conjunctival (plical) tumor in the left eye. An excision biopsy of the tumor was performed. Results Histopathology of the excised tumor revealed reactive lymphoid hyperplasia. Discussion Conjunctival lymphomas can masquerade as chronic conjunctivitis and can be preceded by reactive lymphoid hyperplasia. It is important to identify and differentiate these tumors. This report describes the unusual occurrence of a lymphoid conjunctival tumor after LASIK eye surgery.  相似文献   
105.
目的:对胸腔积液进行细胞形态学、生物化学、肿瘤标志物的检测,探讨其结果在诊断恶性肿瘤方面的临床意义。方法:胸腔积液细胞形态学检测采用离心推片法及瑞氏-姬姆萨复合染色鉴定细胞性质;LDH、TP、Cl、ALB、TC、Crp生物化学指标在奥林巴斯2700全自动生化分析仪上检测;CEA、CYFRA21-1、NSE肿瘤标志物在Elecsys 2010上检测,FDP检测采用酶联免疫胶乳凝集法。结果:在选择的60例胸腔积液标本中,有30例胸腔积液为恶性肿瘤,查到癌细胞24例,检出率80%,与病理学、影像学恶性肿瘤诊断符合率为95%,但是未查到癌细胞并不一定能排除恶性肿瘤,本组资料的癌细胞阳性率为80%(24/30)。LDH阳性率为67%(20/30),FDP阳性率为47%(14/30),CEA阳性率为50%(15/30),CYFRA21-1阳性率为77%(23/30)。TP、Cl、ALB、TC、Crp、NSE的检测在鉴别肿瘤方面无显著性差异(P>0.05)。结论:查到癌细胞和CEA、CYFRA21-1、LDH、FDP的联合检测在鉴别恶性肿瘤方面有显著性差异(P<0.01),为恶性肿瘤的鉴别诊断提供了可靠依据。因此在临床诊断中综合分析这些指标可作为恶性肿瘤诊断的依据,值得大力推广。  相似文献   
106.
The concentration of mRNA of insulin-like growth factor-II is (IGF-II) much elevated in some embryonic tumours such as Wilms tumour (nephroblastoma). In order to prove whether or not IGF-II is produced by the tumour tisue, IGF-II was extracted from freshly frozen tissue of Wilms tumour and hepatoblastoma. Normal adjacent tissue of kidney and liver was used as a control. The total IGF-II in Wilms tumour was 548.4±77.4 ng/g (n=7) compared to 112.8±38.2 ng/g (n=5) in kidney. In two hepatoblastomas, it was 96.1±22.8 ng/g compared to 30.1±14,2ng/g in normal liver. Small pieces of fresh primary tissue of several Wilms tumours were successfully transplanted into immunodeficient nude mice. In serum of tumour-bearing mice IGF-II was elevated compared to normal mice. Liver weight of tumour bearing mice was higher than that of control mice (2.29±0.4g and 2.02±0.06 g;P<0.005). This was also found for kidney weight (0.58±0.01 g vs. 0.51±0.01 g in controls,P<0.001). In contrast, serum glucose (9.73±0.29 mmol/l compared to 11.80±0.42 mmol/l in controls,P<0.0005) was decreased. However, there was no significant difference in nose-tail length of tumour-bearing compared to control mice. These results demonstrate that besides the highly increased IGF-II-mRNA, the synthesis of the peptide IGF-II and its release into circulation are also elevated in Wilms tumour transplanted into nude mice. Elevated circulating IGF-II is likely to stimulate growth of some inner organs and has a glucose lowering effect but does no stimulate skeletal growth. This is further evidence for the importance of IGF-II as a growth factor.  相似文献   
107.
A newborn who was operated upon for a benign sacrococcygeal teratoma at the age of 2 weeks developed haemodynamic instability with a shock episode at the time of operation. The serum level of tumour necrosis factor alpha (TNF-Alpha) during this event rose to 158 pg/ml (normal <15 pg/ml). Preoperatively TNF-Alpha was undetectable, while post-operatively the level was 23 pg/ml. Serum levels of the cytokine interleukin-1 beta (IL-1 beta) were undetectable throughout the study. The baby was treated successfully by fluid challenge and dopamine. This case represents a temporal association between haemodynamic instability during surgical intervention and a high serum level of TNF-Alpha, which is an important mediator in the pathogenesis of septic shock.  相似文献   
108.
The management of patients with treated malignant lymphomas requires functional methods to differentiate a residual soft tissue mass. Patients with treated Hodgkin's lymphoma (HL,n = 20, 68 malignant lesions, three benign lesions) or non-Hodgkin's lymphoma (NHL,n = 26, 46 malignant lesions, one benign lesion) were studied with positron emission tomography (PET) and fluorine-18 deoxyglucose (FDG). Oxygen-15 labelled water was used (n = 14, 25 lesions) in addition to FDG in order to obtain information on the tissue perfusion. Long-term follow-up studies with PET and FDG were performed in nine patients up to 511 days after the initiation of second-line therapy. Fourteen patients underwent single-photon emission tomography (SPET) with technetium-99m sestamibi immediately prior to the first PET examination. PET with FDG displays a high sensitivity for the detection of viable tumour tissue, all the malignant lesions being correctly classified in this study. The possible limitations are inflammatory processes, which may obscure tumour detection due to increased FDG uptake, and malignant lesions with low FDG uptake due to reduced perfusion. Difficulties exist in the prognosis of long-term response, since the change in FDG uptake may be variable. Long-term therapy outcome was correlated with the slope values obtained from the standardized integral uptake (SIU) data, which provides a new approach for the evaluation of PET follow-up studies.99mTc-sestamibi, which should reflect the multidrug resistance, was evaluated with respect to therapy outcome. A high uptake of99m-Tc-sestamibi was observed in patients with stable disease or better. The data support the hypothesis that sestamibi may reflect multidrug resistance. Due to technical limitations of the SPET technique, the use of a positron-labelled compound would be superior to SPET for clinical application.  相似文献   
109.
The blood-retinal barrier (BRB), which is formed by the retinal vascular endothelium and the retinal pigment epithelium, is responsible for controlling the passage of cells and molecules into the neuroretina. During ocular inflammatory diseases, however, this selective control is altered due to changes in BRB function such as increased permeability and leucocyte recruitment. The causative factors leading to barrier breakdown are not entirely understood although cytokines have recently been implicated. We have investigated the effect of the cytokines tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) upon the integrity of the rat BRB. Lewis rats received a dose of each cytokine by intravitreal injection and the permeability of the BRB was assessed using the small molecular weight vascular tracer 14C mannitol. A significant opening of the barrier to mannitol was detected following an intravitreal injection of 2 × 104 U of TNF-α which persisted from day 1 to day 5 post-injection (PI). The permeability of the BRB returned to normal values by day 7 PI. Only occasional mononuclear inflammatory cells were seen in the retina and vitreous of the TNF-α-treated eyes although they remained in evidence up to day 5 PI. In the TNF-α-injected eye there was immunohistological evidence of activation of tissue-resident cells, particularly in the inner plexiform layer. Of particular interest was the observation that the BRB of the non-injected contralateral eye also exhibited increased permeability over a similar time-course but without any evidence of cellular infiltration or activation of tissue-resident cells. Unlike TNF-α, the administration of 1 × 103 U of IL-6 into the vitreous caused no measurable increase in BRB permeability despite inducing a small infiltration of inflammatory cells. Received: 21 November 1995 / Accepted: 13 December 1995  相似文献   
110.
The vasculature of B16, a murine melanoma and Mel-mo, a human melanoma, was studied using intravital staining of patent capillaries by the fluorescent bisbenzamine dye Hoechst 33342. Capillaries were numerous at the edge of tumours in both the lines studied, but were scarcer within the nodules. Vascular volume as a proportion of total tumour volume was estimated by means of point counting. In both B16 and Mel-mo, the percentage vascular volume was inversely related to log tumour weight. Tumour necrosis, which increased with tumour size, was inversely correlated with percentage vascular volume, emphasizing the central under-perfusion of these experimental tumour nodules. This pattern of perfusion, with greater density of functioning capillaries at the periphery of tumour nodules, was seen in both the tumour lines examined despite differences in the degree and pattern of necrosis.  相似文献   
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