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41.
目的:观察卡托普利(CaP)对自发性高血压大鼠(SHR)血管平滑肌细胞(VSMC)增殖的作用及对原癌基因及抑癌基因的影响。方法:氚-胸腺嘧啶核苷(3H-TdR)参入,电镜,原位来交及Northernblot杂交。结果:CaP在降低SHR血压同时,能减少VSMC的线粒体,粗面内质网及3H-TdR参入量(P<0.01),并能逆转c-fos,c-myc,c-sis原癌基因mRNA表达增强(P<0.05或0.01),p53抑癌基因mRNA表达减弱(P<0.01)。结论:Cap能抑制SHR的VSMC增殖,与癌基因调控的分子生物学机制有关。  相似文献   
42.
Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response.  相似文献   
43.
分析原发性腹膜后恶性肿瘤12例。83%以腹块和腹痛为主要症状,体征中腹块占91.5%,以恶性淋巴瘤居首位占61%。全组完全切除率为58%,行脏器联合切除占25%。完全切除加放疗、化疗3年存活率为28.5%,部分切除及活检未给其它治疗者5例预后差,均1年内死亡,差别显著。  相似文献   
44.
Summary Cytochemical staining of normal human bone cells in monolayer cultures for alkaline phosphatase (ALP) indicated that the cultures contained mixed-cell populations. Time course evaluations of the cytochemical staining revealed, in addition to the ALP-negative cell population, at least two subpopulations of ALP-positive human bone cells with different levels of ALP. A cytochemical method has been developed which separates the ALP-positive cells into high and intermediate ALP subpopulations. In this method, human bone cells were stained for ALP using an azo-dye method and incubating at 4°C for 10 and 30 minutes, respectively. We defined the cell population that stained positively for ALP at 10 minutes as strong ALP-positive cells, and both strong and intermediate cells were stained at 30 minutes. The intermediate cells were determined from the difference between the values at the two time points. The intra- and interassay variations of the assay, with the same investigator in blinded investigations, were both less than 10% and the interobserver variation was approximately 25%. Analysis of the distribution of ALP levels in cells with a laser densitometer confirmed the presence of at least three cell subpopulations. 1,25(OH)2D3 treatment increased the proportions of both ALP-positive cell populations, whereas TGF-beta treatment increased only the intermediate ALP-positive cell population. On the contrary, fluoride increased the proportion of the strong ALP cells, and IGF-1 had no effect on the proportions of either ALP-positive subpopulation. When the ALP-specific activity was compared with the percentage of each ALP-positive subpopulations for the cells treated with effectors, the ALP-specific activity correlated with the total ALP-positive and with the strong ALP-positive populations but not with the intermediate ALP-positive subpopulation. In summary, this study represents the first evidence that normal human bone cells in monolayer cultures contained at least two subpopulations of ALP-positive cells, and that bone cell effectors could have differential effects on each cell population.  相似文献   
45.
Effect of distension on adrenergic innervation of the rat urinary bladder   总被引:1,自引:0,他引:1  
Summary The effect of distension on adrenergic innervation was investigated in the rat urinary bladder. Bladders were distended for 3 h by forced diuresis and ballon obstruction, and specimens were taken from the bladder dome, body and neck for the demonstration of glyoxylic acid-induced fluorescence of catecholamines. Depletion of catecholamines started after 10 h and was almost complete after 2 days. The fluorescence had recovered part way after 5–7 days and was practically normal after 21 days. Small, intensely fluorescent (SIF) cells in the ganglia continued to leak catecholamines throughout the 21-day study period. The primary clinical success of distension therapy for the treatment of unstable bladder may be at least partly due to a reversible disturbance in the function of the adrenergic nerves, which have an excitatory alpha-adrenergic dominance in such cases, but the persistent leakage from SIF cells raises the question of whether distension causes prolonged disturbances in bladder function.  相似文献   
46.
47.
卵巢恶性肿瘤与血小板增多关系分析   总被引:1,自引:0,他引:1  
目的探讨卵巢恶性肿瘤伴发血小板增多的临床规律。方法回顾分析98例卵巢恶性肿瘤患者的临床资料,26例合并血小板增多。结果血小板增多占26.5%,其中晚期(Ⅲ+Ⅳ期)占88.46%,晚期患者血小板偏高明显增多,且肿瘤切除后血小板下降。结论卵巢恶性肿瘤伴发血小板增多晚期患者多见,预后差,血小板增多可作为判断卵巢肿瘤恶性程度及术后随访的指标。  相似文献   
48.
Enhanced and non-enhanced computed tomography (CT) brain scans were performed within 72 h of surgery on 21 children in whom brain tumors had been resected totally or subtotally, and scans were repeated at varying intervals thereafter. Biopsies of the resection margins were performed in 12 patients at the end of the surgical procedure. The immediate CT scan showed enhancement in the resection margin in 13 of the 21 patients and in 9 of the 13, the enhancement disappeared on follow-up scans. There was discordance between the results of immediate CT scan examination and the biopsies of the resection margins in 7 of the 12 cases. The advantages and disadvantages of an immediate postoperative scan versus a more delayed CT scan are discussed.  相似文献   
49.
A case of papilliferous keratoameloblastoma is reported which is only the second ever documented. The patient was a 76-yr-old black woman with a large expansile multilocular radiolucency of the body, angle and ramus of the mandible. Histologically the lesion consisted of sheets of cystic follicles filled with necrotic debris and sometimes parakeratin. The vast majority of the follicles were lined by a papilliferous epithelium consisting of large rounded cells with centrally placed nuclei. True papillary projections with cores of connective tissue were also present. The remainder of the follicles were lined by a thin parakeratinising stratified squamous epithelium. Histological features characteristic of ameloblastoma were absent. Final classification of these lesions will have to await the reporting of further cases.  相似文献   
50.
来源于骨髓和脐带血的基质细胞基本特性的比较   总被引:5,自引:0,他引:5  
目的比较骨髓与脐带血细胞体外培养基质细胞的基本特性,为基质细胞的选择应用提供依据.方法用Dexter长期培养体系培养骨髓和脐带血基质细胞,以细胞增殖、细胞形态、细胞化学染色、细胞表面及基质细胞支持另一骨髓细胞形成的鹅卵石造血区(CAFC),长期培养起始细胞(LTC-IC)为指标,比较两者的生长特性、成分及功能.结果①细胞生长特性:出现贴壁细胞时间,骨髓细胞为培养3d,脐带血细胞为培养5~6d;细胞融合成片时间,骨髓细胞为培养10~14d,脐带血细胞为培养12~18d;第21天细胞增殖数,骨髓比脐带血细胞增殖少;②细胞成分:21d培养后细胞成分,骨髓来源者以成纤维细胞为主,其次是巨噬细胞与内皮细胞,脂肪细胞最少;脐带血细胞来源者,以巨噬细胞为主,其次是内皮细胞、成纤维细胞,偶见脂肪细胞;细胞化学与上述结果基本一致;细胞表面抗原检测,CD14、CD45的表达骨髓细胞明显低于脐带血细胞;③细胞功能:骨髓来源的基质细胞较脐带血细胞的基质细胞支持另一骨髓细胞形成的CAFC和LTC-IC明显多.结论①生长特征:形成贴壁细胞时间骨髓较脐带血短,骨髓细胞比脐带血细胞有核细胞数增殖快、持续时间相对短;②细胞成分特性:骨髓来源形成的基质细胞以成纤维细胞为主,脐带血来源者以巨噬细胞为主;③细胞功能特性:骨髓细胞形成的贴壁细胞较脐带血细胞形成的贴壁细胞更利于CAFC、LTC-IC生长.  相似文献   
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