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81.
A total of 125 patients with severe peripheral vascular disease were examined with translumbar aortography. The mean dose of contrast medium injected was 65 ml of Angio Conray (containing 31.2 g of iodine). Forty patients were pretreated with mannitol, and 32 received furosemide. Thirty-eight patients (30%) had diabetes and, presumably, diabetic nephropathy. Eleven of them had significant azotemia (creatinine values greater than or equal to 4 mg/dl). Administration of contrast material did not significantly reduce renal function in any patient group. We conclude that acute renal failure following the injection of contrast material is uncommon, is reversible, and almost always occurs when avoidable complicating factors are present. 相似文献
82.
83.
P. Mainenti G.S. Oliveira J.B. Valério L.S.L. Daroda R.F. Daroda G. Brandão L.E.B. Rosa 《International journal of oral and maxillofacial surgery》2009,38(3):289-292
This paper reports one case, of an ameloblastic fibro-odontosarcoma (AFOS) affecting the mandible, in a 12-year-old girl. This neoplasm is a rare odontogenic neoplasm. To the authors’ knowledge this is the fifteenth case of AFOS reported in English. The patient's chief complaint was a swelling in the face for 6 months. An incisional biopsy was performed diagnosing the case as an ameloblastic fibroma. After radiography ameloblastic fibro-odontoma was diagnosed. Computed tomography was performed and a stereolithography model made to plan the surgical procedures. A hemimandibulectomy followed by a vascularized fibular flap was then proposed. The surgery was uneventful. Microscopic features diagnosed an AFOS. After 23 months of close follow-up there is no sign of recurrence or metastasis. Dental implants were recently placed in the fibular flap. 相似文献
84.
维拉帕米对大鼠肝脏贮脂细胞增殖及胶原基因表达的影响 总被引:2,自引:0,他引:2
在肝纤维化的发生发展过程中,细胞外基质的过度合成和异常沉积是最主要的病理过程。研究表明,病理状态下,贮脂细胞(FSC)被激活,数量增多,分泌大量的胶原等细胞外基质,导致肝纤维化的发生、发展[1]。材料和方法一、实验动物雄性SD大鼠10只,其中5只皮下注射40%CCl4茶油溶液建立肝纤维化模型。二、试剂链霉蛋白酶和Nycodenz购于Sigma公司;胶原酶购于上海医工院;维拉帕米(Ver)购于Knoll公司;RNA提取剂、P32dCTP、随机引物标记试剂盒购于Gibco、亚辉、Promega公司三… 相似文献
85.
新生牛跟腱胶原蛋白海绵与细胞的生物相容性 总被引:1,自引:1,他引:1
目的:采用新生牛跟腱制备生物医用胶原蛋白海绵,通过分别接种Vero细胞、天祝白牦牛胚胎皮肤原代细胞和岷县黑紫羔羊睾丸原代细胞至胶原蛋白海绵组织支架上,观察新生牛跟腱胶原蛋白海绵与3种细胞的生物相容性。方法:实验于2006-02/05在西北民族大学生命科学与工程学院生物工程与技术国家民委重点实验室完成。①用新生牛跟腱经冰醋酸、胃蛋白酶等消化,经盐析、透析及冻干等处理后,制备成胶原蛋白海绵。②在六孔板中,将Vero细胞、天祝白牦牛胚胎皮肤原代细胞和岷县黑紫羔羊睾丸原代细胞分别接种于经紫外线、臭氧灭菌后的胶原蛋白海绵上,经37℃体积分数为0.05的CO2恒温培养;并用另一组细胞在凯氏瓶中培养作对照实验。用奥林帕斯倒置相差显微镜及JVC摄像系统观察、拍摄与记录细胞生长情况,并于培养11d,用考马斯亮蓝和苏木精-伊红染色,证实相差显微镜观察的结果。结果:①胶原蛋白海绵制备结果:用新生牛跟腱制备得到具有一定孔隙度的胶原蛋白海绵,经紫外线、臭氧灭菌后可进行细胞培养。②3种细胞在胶原蛋白海绵上和六孔板底的生长情况:3种细胞接种后5h,在胶原蛋白海绵周围的六孔板孔底可看到Vero细胞已贴壁、伸展,个别细胞有分裂现象,在胶原蛋白海绵表面,隐约可见圆形细胞排列。Vero细胞和天祝白牦牛胚胎皮肤原代f2细胞接种72h、岷县黑裘皮羔羊睾丸原代f2细胞接种48h时,孔底细胞已经铺满单层,但与对照孔比较,生长速度较慢。②3种细胞用考马斯亮蓝细胞骨架染色和苏木精-伊红染色的结果:培养到第11天,3种来自不同动物、不同组织的细胞接种的胶原蛋白海绵支架孔中均有大量细胞良好生长,胶原海绵外观变得挺拔、透明、有韧性。结论:新生牛跟腱胶原蛋白海绵,对Vero细胞、天祝白牦牛胚胎皮肤原代细胞和岷县黑紫羔羊睾丸原代细胞无毒性,3种细胞均能在其上良好生长,但在体内是否会引起免疫排斥反应,还有待进一步研究。新生牛跟腱有望成为医用胶原蛋白海绵产品新的原材料。 相似文献
86.
Association between gelatinase release and increased plasma membrane expression of the Mo1 glycoprotein 总被引:7,自引:0,他引:7
Mo1, a glycoprotein heterodimer (gp 155,95) that functions as an adhesion promoting molecule and as the C3bi receptor of human myeloid cells, is expressed in increased amounts in the plasma membrane after exposure of polymorphonuclear leukocytes (PMNs) to various stimuli. Previous studies have suggested that secondary granules represent an intracellular pool of Mo1 that, upon degranulation, fuse with the plasma membrane resulting in a tenfold increase in surface expression of Mo1. To determine the intracellular location of Mo1, we monitored Mo1 expression by immunofluorescence and compared it to the release of myeloperoxidase (MPO, a marker for the primary granules), vitamin B12 binding protein (B12BP, secondary granules), and gelatinase (gelatinase- containing organelles) following exposure to various stimuli. Human neutrophils stimulated with 20 mmol/L fluoride for 16 minutes exhibited a twofold increase in Mo1 expression and gelatinase release but no enhanced release of primary or secondary granular contents. In a similar fashion, incubation of cells at 37 degrees C for five minutes with 7.5 X 10(-9) to 10(-6) mol/L N-formyl-methionyl-leucyl- phenylalanine (FMLP) resulted in significant increases in both surface Mo1 expression (three- to fivefold) and gelatinase release (five- to eightfold) without significant release of either MPO or B12BP. In addition, both the fluoride and FMLP experiments demonstrated that Mo1 up-modulation alone is not sufficient to activate superoxide (O2-) production. These data indicate that at least one intracellular storage pool of Mo1 is the gelatinase-containing organelles and that their fusion with the plasma membrane results in increased expression of Mo1 on the cell surface. 相似文献
87.
Absence of human T-cell lymphotropic virus type I coinfection in human immunodeficiency virus-infected hemophilic men 总被引:2,自引:0,他引:2
Concern for transmission of human T-cell lymphotropic virus, type 1 (HTLV-1) infection to recipients of infected cellular blood products has prompted development of tests to eliminate blood units with HTLV-I antibodies. Most hemophilic men from the United States became infected with human immunodeficiency virus (HIV) before HIV donor screening and before blood products were processed to inactivate the virus. To assess whether these men might also be infected with HTLV-I, we examined the HTLV-I antibody status of 127 factor VIII (hemophilia A) recipients and 71 factor IX (hemophilia B) recipients. One HIV-seronegative and four HIV-seropositive persons were HTLV-I reactive by enzyme-linked immunosorbent assay (ELISA). Four of five ELISA-reactive serum samples were negative by HTLV-I immunoblot assay (IB); 1 reactive and 1 borderline reactive serum were indeterminate on IB (p19 reactivity), but negative by radioimmunoprecipitation assay (RIPA). Peripheral blood mononuclear cells from one patient with indeterminate HTLV-I IB were negative for HTLV-I genomic sequences by polymerase chain reaction. The other indeterminate patient's serum antibody pattern was stable over a 2-year period, suggesting this was not an instance of early HTLV-I seroconversion. These results reaffirm the safety of factor components in the United States with regard to HTLV-I but emphasize the importance and need for further testing of reactive HTLV-I ELISA results with a second more specific technique. 相似文献
88.
Enzyme-linked immunoabsorbent assay detection of a soluble form of urokinase plasminogen activator receptor in vivo 总被引:9,自引:0,他引:9
The receptor for urokinase plasminogen activator (uPA-R, CD87) is a glycosylphosphatidylinositol (GPI)-anchored 50 to 65 kD glycoprotein that, by regulating membrane-associated plasmin activity, may facilitate the invasion of inflammatory and malignant cells. Certain other GPI-anchored glycoproteins are shed from the cell membrane and exist as soluble products in vitro and in vivo. To determine if uPA-R undergoes a similar phenomenon, we have developed a sensitive enzyme- linked immunoabsorbent assay (ELISA) (using a rabbit antiserum as both capture and detection reagents) to measure the quantity of soluble uPA- R (suPA-R) in tissue culture supernatants and biologic fluids. Using this ELISA, we have detected suPA-R in the culture supernatants of U- 937 cells and human monocytes stimulated in vitro by certain soluble inflammatory mediators (Sitrin et al, Blood 84:1268, 1994; Mizukami et al., Clin Res 42:115A, 1994). To determine if suPA-R exists in vivo, we have screened the plasma of 20 normal volunteers (mean +/- SD, 3 +/- 3 ng/mL; median, 2 ng/mL; range, 1 to 11 ng/mL [serum values slightly higher]); the plasma of 13 ICU patients with clinical sepsis syndrome (mean +/- SD, 30 +/- 11 ng/mL; median, 11 ng/mL; range, 4 to 221 ng/mL); and the extravascular fluids (pleural, pericardial, and peritoneal) of 84 individuals with presumed inflammatory or malignant conditions (mean +/- SD, 21 +/- 39 ng/mL; median, 10 ng/mL; range, 2 to 253 ng/mL). Among the latter specimens, most were inflammatory exudates (only six were malignant by positive cytology) with the highest quantities of suPA-R associated with neutrophilic exudates. The solubility of suPA-R contained within these fluids was confirmed by reanalysis after ultracentrifugation to remove particulate material. When tested in a uPA ligand capture ELISA, representative specimens of extravascular body fluids and sepsis plasma contained suPA-R capable of binding uPA ligand (generally representing a small fraction of the immunoreactive material). We conclude from these data that suPA-R is immunologically detectable in vitro and in vivo with high concentrations of receptor found under conditions of inflammatory stimulation. The possibility of suPA-R's biologic activity is suggested by its partial retention of ligand binding capacity. 相似文献
89.
A 43/4-yr-old black girl with acquired aplastic anemia had an increase in total hemoglobin (Hb) from 4.5 to 16.8 g/dl and fetal hemoglobin (HbF) from 0.8 g/dl (18.8%) to 9.6 g/dl (60.2%) following combined androgen-adrenal steroid therapy. Discontinuation of the drugs was followed by a decline in both HbF and total Hb. Reinstitution of the combined steroids prompted a second rise in total and fetal hemoglobin. During these responses the subject's erythrocytes exhibited an increased i antigen score and a low level of red cell carbonic anhydrase. The glycine:alanine ratio at position 136 of the gamma chains of HbF was of the fetal type (proportion of chains with glycine residues, 0.74). Hemoglobin A2 was low (0.4%). The synthesis of alpha and non-alpha chains was balanced. These results indicate that the stimulation of red cell proliferation in this subject, in response to androgen therapy, resulted in the production of cells with several characteristics of "fetal" erythrocytes. 相似文献
90.
A subject with HbG Philadelphia-HbH disease exhibited an unusually high alpha/beta synthesis ratio; when peripheral blood was tested in vitro on several occasions, ratios of 0.63 - 0.89 were obtained after incubations of 30-120 min. HbH amounted to 5%-8% of the circulating hemoglobin. Rapid destruction of excess newly synthesized beta-globin was demonstrated in kinetic and pulse-chase experiments. After 2 min of incubation, the alpha/beta synthesis ratio was 0.48; this figure rose to 0.89 by 30 min. The zero time alpha/beta ratio was estimated to be 0.35. The degradation of beta-chains was calculated to proceed at approximately one-half the rate of beta-globin synthesis; this result was confirmed by the loss of 50% of the specific activity in beta- chains during 9 min of a chase experiment following a 10-min radioactive pulse. The results suggest that efficient proteolysis may be responsible, in some blacks, for the low levels of excess beta- globin chains in HbH disease as well as for the mildness of the clinical disorder. 相似文献