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31.
在我国,终末期肾脏病的发病率逐年增加,相应地,腹膜透析病人的数量也在不断增长。明确腹膜透析病人预后的影响因素是临床医师亟待解决的重要课题。尿毒症毒素的积蓄可对腹膜透析病人的心血管系统产生不良作用,影响病人的生活质量。腹膜透析充分性的相关指标对于预测病人的生存率也有一定的指导意义。此外,腹膜炎的发生可使超滤量明显下降,增加病人的死亡率。合并症可能通过加重病人的营养不良状态、促进炎症水平,影响病人的预后。因此,重视病人的尿毒症毒素水平、透析充分性指标与合并症情况,积极防治腹膜炎,将有助于改善腹膜透析病人的预后。  相似文献   
32.
目的:探讨骨化三醇联合腹膜透析疗法治疗慢性肾功能衰竭的临床疗效及对患者血清Pro-Gastrin-Releasing Peptide (ProGRP)、CystatinC(Cysc)、Chemerin水平的影响。方法:选取我院2017年2月至2018年1月收治的98例慢性肾功能衰竭患者,按照随机数表法将其分为观察组(n=51)和对照组(n=47)。对照组采用腹膜透析疗法治疗,观察组采用骨化三醇联合腹膜透析疗法治疗。观察和比较两组治疗前后肾功能指标尿素氮(blood urea nitrogen,BUN)、血清肌酐(Serum creatinine Cr)、24小时尿蛋白(24 h urinary protein,24 h UP),生化指标白蛋白(albumin,Alb)、血红蛋白(hemoglobin,Hb)及红细胞(red blood cell,RBC),胃泌素释放肽前体(ProGRP)、血清胱抑素(Cys C)、趋化素(Chemerin)水平的变化,6个月、1年生存率及不良反应的发生情况。结果:治疗后,观察组BUN、SCr、24hUP水平均显著低于对照组[(13.95±3.06)mmol/L vs.(21.10±3.85)mmol/L,(260.12±40.32)μmol/L vs.(354.93±51.06)μmol/L,(1.75±0.45)g/24 h vs.(2.67±0.80)g/24 h](P0.05);Alb水平显著低于对照组[(27.85±3.58)g/L vs.(33.06±4.27)g/L](P0.05);Hb、RBC显著高于对照组[(91.72±13.46)g/L vs.(82.36±10.15)g/L,(379.47±92.08)×1012/L vs.(315.70±73.24)×1012/L](P0.05);ProGRP、Chemerin水平显著低于对照组[(49.23±4.72)pg/mL vs.(63.87±7.30)pg/mL,(37.02±6.15)μg/L vs.(30.63±4.81)μg/L](P0.05);Cysc水平显著高于对照组[(80.75±16.08)mL/min vs.(98.81±18.07)mL/min](P0.05);6个月、1年生存率均显著高于对照组[96.08%(49/51) vs. 91.49%(43/47),90.20%(46/51) vs. 74.47%(35/47)](P0.05);不良反应总发生率显著低于对照组[17.65%(9/51) vs. 44.68%(21/47)](P0.05)。结论:骨化三醇联合腹膜透析疗法治疗慢性肾功能衰竭的临床效果显著优于单用,其可有效减轻患者的临床症状,纠正电解质紊乱,改善肾功能和预后,可能与降低血清ProGRP、Chemerin水平及提高血清Cysc水平有关。  相似文献   
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34.
This paper is designed to provide an overview of the main membrane-assisted processes that can be used for the removal of toxic inorganic anions from drinking water supplies. The emphasis has been placed on integrated process solutions, including the emerging issue of membrane bioreactors. An attempt is made to compare critically recently reported results, reveal the best existing membrane technologies and identify the most promising integrated membrane bio/processes currently being under investigation. Selected examples are discussed in each case with respect to their advantages and limitations compared to conventional methods for removal of anionic pollutants. The use of membranes is particularly attractive for separating ions between two liquid phases (purified and concentrated water streams) because many of the difficulties associated with precipitation, coagulation or adsorption and phase separation can be avoided. Therefore, membrane technologies are already successfully used on large-scale for removal of inorganic anions such as nitrate, fluoride, arsenic species, etc. The concentrated brine discharge and/or treatment, however, can be problematic in many cases. Membrane bioreactors allow for complete depollution but water quality, insufficiently stable process operation, and economical reasons still limit their wider application in drinking water treatment. The development of more efficient membranes, the design of cost-effective operating conditions, especially long-term operations without or with minimal membrane inorganic and/or biological fouling, and reduction of the specific energy consumption requirements are the major challenges.  相似文献   
35.
This study examined primary cilia on cultured human and rabbit peritoneal mesothelial cells (PMC) and investigated factors that influence ciliary expression. Primary cilia were examined with indirect immunocytochemistry, laser scanning confocal microscopy and scanning electron microscopy. Ciliary expression was evaluated in cultures with or without l-cysteine (0.25 mM) or exposure to Ca(2+)-free Krebs-Ringer solution supplemented with EGTA, 0.5 mM. This treatment disrupted cell monolayer integrity. Cilia were counted and normalized to total cell counts using NIH image. Primary cilia were identified on both human and rabbit PMC. Cells treated with l-cysteine expressed significantly more cilia compared with monolayers deprived of l-cysteine. Exposure to Ca(2+)-free Krebs-Ringer solution significantly reduced cilia (5.9+/-1.0%, n=7). Although ciliary expression could be augmented with l-cysteine, approximately 60% of human PMC and 84% of rabbit PMC did not exhibit cilia. Together, these data show that monolayers of PMC express apical cilia that can be augmented with l-cysteine, independently of increased cell density.  相似文献   
36.
Groups of rats were injected intraperitoneally with cell wall-deficient (L) forms of Streptococcus pyogenes, with their parental (S) forms, as well as with a combined inoculum of both forms (S+L). Peritoneal exudate samples were harvested on days 1, 3, 7, 15 and 30 after challenge and were investigated by microbiological, electron microscopic, cytometric and biochemical methods. Parental S forms were isolated from peritoneal exudate samples up to day 15 post infection, while L form cultures were isolated until the end of the examined interval. Electron microscopic examination revealed continuous adhesion of L forms on the macrophage surface as well as intracellular persistence inside them. It was demonstrated that the intraperitoneal inflammatory response to L form infection was higher than to the other infections and the monocyte-macrophage populations were predominant. The established atypical behaviour and long survival of S. pyogenes L forms in the rat's peritoneum could explain some of the mechanisms of the pathogens' persistence as well as the reasons for chronic streptococcal infections.  相似文献   
37.
透析培养   总被引:4,自引:0,他引:4  
本讨论了有效利用透析技术从发酵液中及时转移低分子杂质混合物,从而获得高密度发酵细胞的方法,章从反应系统、工艺策略、膜相关性能、应用我、生产性放大等方面说明了利用透析技术以达到高浓度细胞发酵的有效性和可靠性。透析技术不仅克服了微孔过滤和超滤中存在的膜孔堵塞弊端,而且如果应用“营养分离”补策略,还可以防止营养物质的损失而使培养基被高效利用,在实验条件下,透析培养的潜力通过两种反应模型进行演示:内置  相似文献   
38.
Protein expression changes induced in thioglycolate‐elicited peritoneal murine macrophages (MΦ) by infection with type III Group B Streptococcus (GBS) are described. Proteins from control MΦ and MΦ incubated 2 h with live or heat‐inactivated GBS were separated by 2‐DE. Proteins whose expression was significantly different in infected MΦ, as compared with control cells, were identified by MS/MS analysis. Changes in the expression level of proteins involved in both positive and negative modulation of phagocytic functions, stress response and cell death were induced in MΦ by GBS infection. In particular, expression of enzymes playing a key role in production of reactive oxygen species was lowered in GBS‐infected MΦ. Significant alterations in the expression of some metabolic enzymes were also observed, most of the glycolytic and of the pentose‐cycle enzymes being down‐regulated in MΦ infected with live GBS. Finally, evidence was obtained that GBS infection affects the expression of enzymes or enzyme subunits involved in ATP synthesis and in adenine nucleotides interconversion processes.  相似文献   
39.
Levels of lysophosphatidic acid (LPA), an important phospholipid mediator, in serum and ascitic fluid from ovarian cancer patients were shown to be higher than those from healthy women and from patients with other type of cancer, respectively. Although LPA in human serum seems mainly to be generated by lysophospholipase D (lysoPLD), the source and pathway for LPA in the ascitic fluid remain still obscure. In this study, we examined whether lysoPLD activity producing bioactive LPA in human peritoneal fluid was significantly elevated under pathological statuses. Lysophospholipase D activity in human peritoneal fluids was measured by quantifying choline released from exogenous lysophosphatidylcholine on their incubation at 37 degrees C. We also compared the activity of lysoPLD in sera from patients with different gynecologic diseases. We found relatively high lysoPLD activity in peritoneal fluids from patients with ovarian cancer, dermoid cyst or mucinous cystadenoma, whereas there were no significant differences in the serum lysoPLD activity among clinical groups and healthy subjects. The lysoPLD in the peritoneal fluid was found to have similar substrate specificity and metal ion requirement to those of serum lysoPLD, that has been identified as autotaxin, a tumor cell-motility stimulating protein. Our results suggest that increased lysoPLD activity in peritoneal fluid from patients with certain gynecologic tumors might be relevant to its potential of tumor progression.  相似文献   
40.
Secreted proteins are important sources for early detection and diagnosis of disease, and as such have received considerable attention. The extraction of low concentration proteins from large volumes of culture media, which are rich in salts and other compounds that interfere with most proteomics techniques, presents a problem for secretome studies. Ultrafiltration, precipitation, and dialysis are three major extraction methods that can be used to overcome this problem. The present study for the first time, compared the merits and shortcomings of these three methods, without bias. Centrifugal ultrafiltration provided the best extraction efficiency, and precipitation provided the highest number of identifiable proteins. The three methods yielded closely related, but different, information on the secretome; thus, they should be considered complementary or, at least, supplementary methods. Three hundred and sixty unique proteins were identified, including 211 potential secreted proteins. Compared with previous studies, this study also identified 42 new secreted proteins. The present study not only offers a reference for the selection of secretome extraction methods, but also expands the secretome database for the investigation of hepatocellular carcinoma.  相似文献   
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