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81.
枸杞多糖对小鼠红细胞免疫功能的影响 总被引:10,自引:0,他引:10
目的 研究枸杞多糖 (LBP)对小鼠红细胞免疫功能的影响。方法 用形态学方法测定LBP对正常小鼠及环磷酰胺 (CY)造成的免疫抑制小鼠的红细胞C3 b受体 (RBC -C3 bR)花环率和红细胞免疫复合物 (RBC -IC)花环率的影响。结果 LBP能明显增强正常小鼠RBC -C3 bR花环率及RBC -IC花环率 ,并能使CY(2 5mg/kg× 3次 )引起下降的RBC -C3 bR花环率及RBC -IC花环率显著回升。结论 LBP能增强小鼠红细胞免疫功能 ,并对CY所致的红细胞免疫功能的抑制具有明显的拮抗作用 相似文献
82.
Summary In 253 normal male subjects mean corpuscular volume decreases as red cell count increases. The result is statistically significant (p<0.005).The work was supported by the Medical Research Council of Canada 相似文献
83.
Vassilis L. Tzounakas Serena I. Valsami Anastasios G. Kriebardis Issidora S. Papassideri Jerard Seghatchian Marianna H. Antonelou 《Transfusion and apheresis science》2018,57(3):347-357
Notwithstanding the high safety level of the currently available blood for transfusion and the decreasing frequency of transfusion-related complications, administration of labile blood products to paediatric patients still poses unique challenges and considerations. The incidence of thalassaemia and sickle cell disease in the paediatric population may be high enough under specific racial and geographical contexts. Red cell transfusion is the cornerstone of β-thalassaemia treatment and one of the most effective ways to prevent or correct specific acute and chronic complications of sickle cell disease. However, this life-saving strategy comes with its own complications, such as additional iron overload, alloimmunization and haemolytic reactions, among others. In paediatrics, the dependency of the transfusion outcome upon disease and other recipient characteristics is more prominent compared with the adults, owing to differences in developmental maturity and physiology that render them more susceptible to common risks, exacerbate the host response to transfused cells, and modify the type or the clinical severity of the transfusion-related morbidity. The adverse branch of red cell transfusion is likely the overall effect of several factors acting synergistically to shape the clinical phenotype of this therapy, including inherent donor/blood unit variables, like antigenicity, red cell deformability and extracellular vesicles, as well as recipient variables, such as history of alloimmunization and inflammation level at time of transfusion. This review focuses on paediatric patients with β-thalassaemia and sickle cell disease as a recipient group with distinct transfusion-related characteristics, and introduces new concepts for consideration, not adequately studied and elucidated so far. 相似文献
84.
Glenda M. Davison Heather L. Hendrickse Tandi E. Matsha 《Transfusion and apheresis science》2018,57(1):58-62
Introduction
Evidence suggests that red cell antigens may act as receptors for viruses and bacteria and therefore could be associated with HIV infection. Previous studies have been controversial and therefore the aim of this exploratory study was to analyse the expression of immunogenic red cell antigens in HIV-seropositive individuals and to compare the results to negative donors from South Africa.Methods
The expression of ABO, Rh, Kell and Duffy antigens from 119 HIV-seropositive patients was compared to 317 HIV-seronegative blood donors. Nucleic acid amplification testing and PCR were used to determine the HIV status and the ID-Gel Card Technology was used to determine the blood group antigen profile.Results
There was no significant difference in the expression of A, B, AB, Duffy or Kel antigens between the two groups but significantly lower numbers of HIV+ individuals were O Rh Negative (p?=?,0.0001). Analysis of those with a Duffy null phenotype revealed a significantly higher incidence of blood type A RH1-Positive, Dce/R0r and B RH1-Positive, DcEe/R2r within the HIV-seropositive group (p?=?<?0.05). None of the HIV-seropositive individuals were O RH1-Negative, dce/rr.Conclusion
In conclusion these initial findings have demonstrated a decreased incidence of blood type O Rh1-negative in HIV?+?individuals which suggests that red blood cell antigens may play an important role in susceptibility to HIV infection. The relationship between red cell antigens and HIV infection however remains complex and therefore larger studies are required to confirm these results. 相似文献85.
The aim of the present study is the identification of plant sterols and the development of an analytical method that allows for the quantification of such family of compounds in oenological matrices. The application of liquid chromatography-atmospheric pressure chemical ionization ion-trap mass spectrometry (LC-APCI-ITMS) to sterol characterization is a useful tool and was selected to perform this research. Sterol separation was achieved using a C8 column with a mobile phase consisting of water and acetonitrile under gradient conditions and column temperature of 35 °C, which leads to analyte elution in less than 25 min. Retention times, precursor ions and MRM transitions of analytes allowed for the identification and sensitive quantitative determination of phytosterols in oenological matrices at trace levels. The method showed a dynamic linear range over the concentration ranges from 0.02 to 320 mg kg−1 for the different parts of grapes and from 8 to 100 ng mL−1 in case of wine. The most abundant phytosterol in all samples was β-sitosterol. The seeds are the richest source of phytosterols having a great amount of β-sitosterol, 314 mg kg−1 fresh berry mass, followed by stigmasterol, fucosterol and campesterol at much lower concentrations (ranging from 3 to 10 mg kg−1). 相似文献
86.
87.
《The Egyptian Rheumatologist》2022,44(4):329-332
Aim of the workTo evaluate hematologic parameters in patients with primary Sjögren's syndrome (PSS) and their association with disease activity.Patients and methodsSixty-five PSS patients and 65 age and sex matched control were studied. Neutrophil to lymphocyte ratio (NLR), mean platelet volume (MPV), red blood cells distribution width (RDW), platelet to lymphocyte ratio (PLR) and platelet count were evaluated. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured. The European league against rheumatism (EULAR) Sjögren's syndrome disease activity index (ESSDAI) was assessed.ResultsThe mean age of patients was 47.8 ± 12.1 years and disease duration 5.71 ± 1.2 years and they were 63 females and 2 males. The mean ESSDAI was 6.4 ± 7.9 (3–25). 11 had neurological involvement. 92.3% of patients received low-dose prednisolone (<10 mg/day) and hydroxychloroquine (HCQ). The mean NLR (1.83 ± 0.8), PLR (131.9 ± 32.5) and MPV (8.82 ± 1.4) in patients was significantly higher than in control (NLR 1.57 ± 0.56, PLR 109.9 ± 24.7 and MPV 7.71 ± 1.3; p = 0.036, p < 0.001 and p < 0.001 respectively). The RDW tended to be higher in patients (13 ± 1.56) compared to control (12.83 ± 1.13) (p = 0.46). There was a significant correlation between ESSDAI with NLR (r = 0.29, p = 0.02), RDW (r = 0.37, p = 0.002), ESR (r = 0.32, p = 0.01) and CRP (r = 0.33, p = 0.007) and between MPV with CRP (r = 0.27, p = 0.03) and between RDW and ESR (r = 0.36, p = 0.003).On regression analysis, NLR and RDW were significant predictors of disease activity (p = 0.01 and p = 0.02 respectively).ConclusionThe MPV, PLR and NLR, were significantly increased in PSS. NLR and RDW can be used as indicators of disease activity. 相似文献
88.
89.
黄芪和丹参注射液联用对早期糖尿病肾病血液流变学和肾功能的影响 总被引:31,自引:0,他引:31
目的 探讨黄芪和丹参注射液联用对早期糖尿病肾病 (EDN)血液流变学和肾功能的影响。方法 将2 0 0 1- 0 3~ 2 0 0 4 - 0 3广东省东莞市人民医院 16 0例EDN患者随机分为治疗组和对照组各 80例。两组均采用饮食控制和糖尿病常规治疗。治疗组加用黄芪和丹参注射液治疗 ,疗程 4周。结果 治疗组血液流变学各项指标较治疗前显著下降 (P <0 0 5或P <0 0 1) ;尿白蛋白排泄率 (UAER)、血肌酐 (SCr)、尿素氮 (BUN)和血脂明显下降 (P <0 0 5或P <0 0 1) ,且明显优于对照组 (P <0 0 1或P <0 0 5 )。结论 黄芪和丹参注射液联用能改善EDN患者的血液流变学、血脂和微循环 ,减少尿白蛋白的排出 ,减轻肾损害 ,改善肾功能。 相似文献
90.
Summary In a companion paper, the shapes of spectrin deficient mouse erythrocytes were described; in contrast to previous assumptions, spherules with tethered microvesicles rather than true spherocytes were found. Thence, spectrin deficient mouse erythrocytes are endowed with an excess of surface area for the given volume but the membrane is assuming a highly positive curvature. Observations during and after the action of enzymes cleaving the red cell surface charge (Neuraminidase, Trypsin, Chymotrypsin) showed that the previously positive membrane curvature, as well as the tendency of the membrane to flow into fingerlike protrusions was completely abolished. The erythrocytes of the spectrin deficient, desialylated mouse erythrocytes assumed a variety of shapes, often discocytic or even stomatocytic, i.e. their membrane presented with negative curvature. However, while these desialylated membranes could be easily deformed (elongated) by shear flow they did not recoil elastically into any definitive configuration after removal of the deforming forces. It is concluded from these observations that spectrin (acting on the inner interface between membrane and cytoplasm) and sialic acid residues (acting on the outer interface between membrane and plasma) exert antagonizing effects on membrane curvature and membrane bending elasticity. Sialic acid residues, strongly charged and situated on the outer side of the cell, produce positive membrane curvature; this observation can most readily be explained by assuming that this mechanical effect is caused by repulsive coulombic forces expanding the outer half of the bilayer. To explain the effect of the spectrin-complex in counteracting positive or in producing negative membrane curvature, a similar expansive coulombic force acting between the highly charged residues has been postulated. Thence, a model for explaining the overall elastic behaviour of the normal mammalian red cell is developed which is based on the assumption of elastic interactions of proteinacous membrane components coupled to the lipid bilayer of the membrane.Supported by Deutsche Forschungsgemeinschaft, Sonderforschungsbereich 109, Project C 7. Dedicated to the memory of the late Professor Marcel Hanns, who not only made possible the measurements of zeta-potential in the present experiments but who, in many discussions of the scientific problems envolved, was very instrumental in shaping the concepts presented in this communication. 相似文献