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991.
转移性癌细胞体外水解酶表达及影响因素的作用   总被引:1,自引:0,他引:1  
目的 为阐明树突状细胞肉瘤 (DCS)细胞在体外培养条件下其水解酶表达的类型及一些影响因素的作用。方法 采用水解空斑法检测 10种特异性蛋白酶抑制剂、不同抗体及基质对 DCS细胞的体外蛋白水解作用的影响。结果 抑肽酶 (aprotinin)、乙二胺四乙酸钠 (EDTA- Na2 )、抑胃酶 ((pepstatin)可显著抑制 DCS细胞的蛋白水解作用。抗泛素抗体、抗 DCS抗体对 DCS的蛋白水解作用无明显影响。在纤粘连蛋白 (FN)、层粘连蛋白 (L N)基质上 DCS细胞铺展良好 ,蛋白水解作用不明显。结论 本实验条件下 ,DCS细胞可表达丝氨酸蛋白酶、金属蛋白酶(非基质水解酶 )、天门冬氨酸蛋白酶的活性。抗泛素抗体、抗 DCS抗体对 DCS细胞的蛋白水解作用无明显影响。不同基质上 DCS细胞水解酶表达状态不同  相似文献   
992.
AAA骨与自体红骨髓复合移植治疗骨缺损   总被引:1,自引:0,他引:1  
目的:探讨同种异体抵抗原脱钙骨(AAA骨)与自体红骨髓复合移植对良性肿瘤刮除后骨缺损修复能力的影响。方法:58例66处长骨良性肿瘤刮除后,其有缺损残腔用AAA骨与自体红骨髓复合物充填,术后随诊42例49处骨缺缺损,每2个月复查X线照片1次,随访时间1~3年。结果:49处骨缺损均有9个月内骨性愈合,平均时间为6个月,优良率达93%。结论:AAA骨与骨髓复合物修复骨缺损,其疗效显著,可视为骨缺损修复的  相似文献   
993.
钛基底对钛-瓷修复体表面色的影响   总被引:1,自引:0,他引:1  
目的 探讨钛金属基底对钛 -瓷修复体表面色是否有明显影响。方法 制作 Dentsply DETREY- Carat瓷粉与钛 -瓷修复体标准试件 ,用 CS- 5型分光光度计测色 ,统计分析测定结果 ,并计算色差。结果 钛金属基底与Ni- Cr金属基底间颜色差异较大 ,但加不透明瓷及牙体瓷后 ,两组试件各色度指标统计学上无显著性差异 ,色差均小于 1.5。结论 钛金属基底对钛 -瓷修复体表面色无明显影响 ,Dentsply两种瓷粉同色瓷间无明显颜色差异。  相似文献   
994.
经蝶窦显微手术治疗垂体侵袭性腺瘤   总被引:2,自引:0,他引:2  
为总结临床经验,报告经蝶窦进路显微手术治疗垂体侵袭性腺瘤18例,其中4例伴有胰岛素依赖型糖尿病。施肿瘤近全切除15例,大部分切除3例,术后追加放射治疗10例,服用溴隐亭治疗5例,术后平均随访3.8年,其中3例(16.6%)平均1.6年复发,二次比额手术治愈,就垂体侵袭性和伴有胰岛素依赖型糖尿病患者经蝶窦显微手术治疗的可行性进行探讨。  相似文献   
995.
慢性鼻窦炎内窥镜手术上颌窦粘膜扫描电镜观察   总被引:18,自引:0,他引:18  
为了对行内窥镜鼻窦手术的慢性鼻窦炎患者上颌窦粘膜的术后超微结构变化进行评价,利用扫描电镜及图像分析技术对16例(20侧)术中和术后上颌窦粘膜及自然孔粘膜的纤毛面积进行定量测定。发现术前上颌窦及其自然孔粘膜纤毛细胞明显减少,杯状细胞,微绒毛细胞增多,部分病例有鳞状上皮化生。术后6个月 ̄1年,大部分病例受损的纤毛细胞明显恢复,纤毛细胞覆盖面积增加,有统计学意义,通过内窥镜手术,改善上颌窦的通气、引流、  相似文献   
996.
Using enzyme-linked immunosorbant assay (ELISA), we measured levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) in middle ear effusions (MEE) from patients with secretory otitis media (SOM) undergoing auripuncture to study the role of cytokines in the pathogenesis of the disease. Significant levels of IL-6 (> 62.5 ng/L) were found in 19 (86.36%) of 22 MEEs and those of TNF-alpha (> 37.5 ng/L) in 19 (70.37%) of 27 MEEs. The mean (+/- s) levels of IL-6 and TNF-alpha were 507.68 +/- 813.11 ng/L and 186.86 +/- 166.93 ng/L, respectively. It revealed that the shorter the course, the higher the concentration of IL-6 in MEE: the longer the course, the higher the concentration of TNF-alpha in MEE. These findings suggested that during the early stages of SOM, IL-6 might participate in the defensive reaction of organism, while TNF-alpha might be closely related to the persistence of SOM, resulting in an excessive inflammatory reaction with a potential for pathological changes. It is concluded that the immunological mechanisms probably play a significant role in the pathogenesis of SOM.  相似文献   
997.
Purpose: Our aim was to examine the potential of the uterine cavity to affect fertilization and early embryo development. Design: A prospective IRB-approved protocol for patients fulfilling study eligibility criteria was used. Methods: Patients studied included those with primary or secondary infertility, aged less than 38 years, with no history of severe male-factor infertility, and with hysterosalpingogram-and laparoscopic-confirmed bilateral proximal tubal occlusion. Superovulation induction was accomplished with a combination of GnRH agonist and menotropins, with serum hormonal and sonographic monitoring. Within 24 hr prior to, and again at the time of, ovulatory hCG administration, progesterone (P4) was given. Sonographic-guided transvaginal retrieval was performed 35 hr after hCG. Between four and six oocytes were returned to the uterine cavity, admixed with sperm, immediately following retrieval. Luteal support consisted of daily P4 administration. Results: Of the 20 patients recruited for the study, all completed the retrieval and transfer procedure. A total of four clinical pregnancies was achieved, with one early first-trimester loss, one late first-trimester loss (Trisomy 14), and two healthy term infants delivered. IVF of surplus oocytes demonstrated a 82.5% fertilization rate and 66.7% cleavage following cryopreservation. Conclusions: Human fertilization can be achieved through direct uterine transfer of gametes. Furthermore, administration of P4 prior to the ovulatory dose of hCG is compatible with in vitro or in vivo fertilization and implantation.  相似文献   
998.
肿瘤转移抑制基因nm23H1产物在人鼻咽癌中表达的研究   总被引:5,自引:0,他引:5  
采用SP免疫组化技术,以NDPK/nm23H1特异的单克隆抗体为探针,对人鼻咽癌中nm23H1的表达及其与颈淋巴结转移的关系进行了研究。结果:31例鼻咽癌中nm23H1基因产物表达的阳性率为41.9%(13/31)。其中无转移组的阳性率为52.3%(11/21),有转移组的阳性率为20%(2/10),两组间具有显著性差异(P〈0.01),而在转移的颈淋巴结组织中nm23H1产物表达极微或无表达,其  相似文献   
999.
Heo K  Lin X  Odle J  Han IK 《The Journal of nutrition》2000,130(10):2467-2470
To examine the kinetics of carnitine palmitoyltransferase-I (CPT-I) and the influence of dietary variables, young pigs (18 kg, n = 20) were fed corn-soybean meal diets supplemented with 40 g soy oil/kg and containing either 136 or 180 g crude protein/kg and either 0 or 500 mg/kg L-carnitine (2 x 2 factorial design). Diets were offered for 10 d (85% of ad libitum); CPT-I activities in liver and skeletal muscle mitochondria were determined, and enzyme kinetic constants (V:(max) and K:(m) for carnitine) were estimated. Kinetics of CPT-I in muscle were not affected by diet (P: > 0.1; carnitine K:(m) = 480 +/- 44 micromol/L). In contrast, the K:(m) for carnitine in liver was increased from 164 to 216 +/- 20 micromol/L by dietary L-carnitine supplementation (P: < 0.01) and from 169 to 211 +/- 20 micromol/L by high protein feeding (P: < 0.05). Dietary L-carnitine increased muscle and liver free carnitine concentrations by 72 and 158% over control concentrations (770 and 80 micro;mol/kg wet muscle and liver, respectively). Because tissue carnitine concentrations were within the range of the respective K:(m) for both liver and muscle tissue, it is inferred that alteration of tissue carnitine concentrations via dietary supplementation could modulate CPT-I activity in young pigs.  相似文献   
1000.
ABSTRACT We quantified the effects of a diet containing animal plasma protein on small intestinal growth and mucosal morphology in early weaned pigs. Ninety-six pigs [14 d old, 4 kg body weight (BW)] were assigned in groups of 32 to three dietary treatments as follows: 1) free access to control diet (C), 2) free access to plasma protein diet (P), and 3) plasma protein, pair-fed to C (PPF). Eight pigs from each group were killed at 2, 4, 8 or 16 d. Over a 16-d period, weight gain in the P group was 43% greater (P < 0.05) than that in C pigs; weight gain was similar in C and PPF groups. Protein intake in the P group was 33% higher (P < 0.05) than that in the PPF group; no significant difference was observed between the C and P groups. Dietary protein conversion efficiencies in both the P and PPF groups were approximately 18% greater (P < 0.05) than those in the C group. Intestinal masses in the three groups did not differ at 2, 4 and 8 d. By 16 d, the jejunal and ileal protein and DNA masses (mg/kg BW) in both the P and PPF groups were lower than those in the C group (P < 0.05). Dietary plasma protein did not affect crypt cell proliferation, crypt depth or villous height in either the jejunum or ileum. However, the intravillous lamina propria cell density in the jejunum was significantly lower (P < 0.05) in P and PPF pigs than in C pigs. Plasma urea concentrations were also 40 and 42% lower (P < 0.05) in the P and PPF groups, respectively, than in the C group. Our results indicate that dietary plasma protein reduces the cellularity of the lamina propria, but not epithelial cell surface of the small intestine. Feeding plasma protein also increased the efficiency of dietary protein utilization, in part, by decreasing amino acid catabolism.  相似文献   
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