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BACKGROUND: In maintenance haemodialysis patients, daily food intake is changeable; however, its relationship with nutritional status is unexplored. This study aimed to evaluate the isolated, long-term effect of daily nutrient intake on nutritional status in haemodialysis patients. METHODS: We performed a prospective 1-year controlled study in 27 chronic haemodialysis patients, without recognized risk factors for malnutrition. Each day for 1 week, four times in the year, we measured protein nitrogen appearance, and assessed dietary protein (DPI) and energy (DEI) intake from dietary diaries. We compared the nutritional outcome of patients spontaneously reducing nutrient intake below the threshold of 0.8 g/kg body weight/day for DPI and 25 kcal/kg body weight/day for DEI during the week (LOW, n = 8), with controls at adequate nutrient intake (CON, n = 19). An interventional 6-month study was then carried out in LOW to verify the cause-effect relationship. RESULTS: All patients showed a day-by-day reduction of whole nutrient intake during interdialytic period, which was mostly relevant in the third interdialytic day (L3). During the 1-year study, even in the presence of adequate dialysis dose and normal inflammatory indexes, body weight (68.0 +/- 5.5 to 65.8 +/- 5.9 kg), serum albumin (3.96 +/- 0.07 to 3.66 +/- 0.06 g/dl) and creatinine (9.2 +/- 1.1 to 8.1 +/- 0.7 mg/dl) significantly decreased in LOW but not in CON. Diaries evidenced in LOW a reduced number of meals at L3 that was explained by the fear of excessive interdialytic weight gain. During the interventional study, daily DPI and DEI increased at L3; this was associated with a significant increment of body weight, and serum albumin and creatinine levels. CONCLUSIONS: In maintenance haemodialysis patients the persistent, marked reduction of daily nutrient intake, even if limited to a single day of the week, is an independent determinant of reversible impairment of nutritional status.  相似文献   
53.
目的 制备甘草蛋白免疫磁性微球,并建立快速、精确的免疫磁性捕获ELISA法检测甘草蛋白。方法 采用种子聚合法合成聚苯乙烯磁性微球,并以兔抗甘草蛋白IgG抗体致敏,制备特异性捕获甘草特征蛋白的免疫磁性微球。以生物素标记抗体为示踪抗体,结合辣根过氧化物酶标亲和素建立ELISA检测系统,用于甘草药材和含甘草中成药中甘草蛋白的分析。结果 利用该方法对甘草药材和中成药中甘草蛋白抗原检测,检测灵敏度达到10ng/mL。结论 免疫磁性捕获ELISA检测技术方便、快速、准确,为生药的品种鉴定及中成药的质量控制提供一种新方法。  相似文献   
54.
毛喉萜对人肝癌细胞增殖影响的实验研究   总被引:1,自引:0,他引:1  
目的 探讨毛喉萜 (Forskolin)的抗肝癌作用。方法 采用克隆形成、MTT比色法观察毛喉萜对SMMC 772 1细胞的作用 ,并利用免疫细胞化学方法检测其对rasp2 1、p5 3蛋白表达的影响。结果 毛喉萜可明显抑制SMMC 772 1细胞的增殖 ,其抑制率与剂量呈正相关 (P <0 .0 1 ) ,经毛喉萜处理后 ,rasp2 1、p5 3蛋白表达均有明显下降。结论 毛喉萜能明显抑制肝癌SMMC 772 1细胞增殖 ,其作用可能与降低rasp2 1、p5 3蛋白表达有关。  相似文献   
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A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia.  相似文献   
57.
目的:探讨妊娠高血压综合征(妊高征)患者血清胰岛素样生长因子(IGF-1)和胰岛素样生长因子结合蛋白-3(IGFBP-3)水平与疾病程度及新生儿出生体重之间的关系。方法:用放射免疫方法测定33例妊高征和32例正常血压妊娠妇女的血清IGF-1、IGFBP-3的水平。结果:重度妊高征组IGF-1显著低于正常组,IGFBP-3在各组间的水平浓度差异均无显著性,但IGF-1与IGFBP-3之间呈正相关。新生儿出生体重随妊高征严重程度的加剧而降低,各组间比较差异有显著性(F=5.453,P=0.002)。结论:妊高征患者的发病及严重程度与IGF-1有明显的关系,IGF-1与胎儿的发育及新生儿出生体重有明显的相关性。  相似文献   
58.
The cause of Alzheimer's disease is unknown. Several factors have been proposed including head trauma. At present, the link between head injury and a subsequent neurodegenerative process is largely circumstantial, except in the case of dementia pugilistica (punch drunk syndrome) found in boxers. Recent studies have shown that the brains of boxers with this syndrome contain large numbers of 'diffuse' beta-protein immunoreactive plaques. We supposed that this plaque type might be associated with trauma induced Alzheimer-like degeneration. In order to test this hypothesis we have re-investigated a previously reported case of post-traumatic premature Alzheimer's disease. Immunocytochemistry using antibodies to amyloid beta-protein revealed large numbers of 'diffuse' non-Congophilic plaques with little or no neuritic component. A similar preponderance of this plaque type is present in the brains of boxers with dementia pugilistica. Our observations support the idea of a trauma induced Alzheimer-like degenerative process and indicate that such a condition is associated with a marked preponderance of 'diffuse' plaques.  相似文献   
59.
Retinol-binding protein (RBP) is the transport protein that carries retinol in the circulation from the liver to its target tissues. The existence of a cell-surface receptor on the target cells, which mediates the uptake of retinol from RBP, has been known since 1975. Recently, it was identified as an integral transmem-brane protein named STRA6 that is inducible by retinoic acid in certain cancer cells. The receptor was found to be highly specific for RBP, with high affinity, and to be localized in all tissues known to require retinol for their function, particularly the pigment epithelium of the eye.  相似文献   
60.
Summary We have developed a novel and reproducible method for determining the plasma protein binding of the two ibuprofen enantiomers in the presence of each other. The method involves the use of radiolabelled racemic ibuprofen, equilibrium dialysis, derivatization of the enantiomers to diastereomeric amides, high-performance liquid chromatography, and radiochemical analysis.We have determined the plasma protein binding of R(–)- and S(+)-ibuprofen in 6 healthy male volunteers after the oral administration of 800 mg racemic ibuprofen.The mean time-averaged percentage unbound of the R(–)-enantiomer, 0.419 was significantly less than that of the S(+)-enantiomer, 0.643, consistent with stereoselective plasma protein binding.The percentage unbound of each ibuprofen enantiomer was concentration-dependent over the therapeutic concentration range and was influenced by the presence of its optical antipode.  相似文献   
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