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1.
海脉冲营养素对小鼠造血功能的影响   总被引:3,自引:3,他引:0  
通过与复方阿胶浆,施普端螺旋藻胶囊抗贫血功效的比较,研究了海脉冲营养素对小鼠造血功能的影响。结果表明,小鼠口服HMC500mg/(kg.d),对失血性贫血小鼠有提高,RBC的作用,对苯肼引起的溶血性贫血小鼠有升高Hb,RBC,WBC的作用,能促进由环磷酰胺所致骨髓抑制小鼠的骨髓有核细胞的增殖,增加脾脏重量,升高外周血中网织红细胞和WBC数量。  相似文献   
2.
Low numbers of parasites from cloned lines of the rodent malaria parasites, Plasmodium chabaudi chabaudi AS and P. yoelii yoelii A, injected into CBA/Ca mice produce acute but usually self-limiting infections. During crisis, i.e. 1-2 days after peak parasitaemia, 'pre-immune' mice experiencing such 'background' infections were reinfected intravenously with homologous parasites or parasites of heterologous strains or species. P. c. chabaudi AS pre-immune mice controlled an AS challenge with essentially the same kinetics as the background infection. Reinfection of AS pre-immune mice with the heterologous (CB and IP-PCI) P. c. chabaudi strains or P. chabaudi adami DS had little effect on the initial growth of these parasites, although eventually the parasitaemia was controlled. In contrast, a partial inhibitory effect on the growth of P. vinckei lentum DS was evident. Challenge with the non-lethal (A) or lethal (YM) variants of P. y. yoelii resulted in an increase in both the growth and virulence of these parasites. P. y. yoelii A pre-immune mice controlled a homologous challenge, but were less effective at controlling the YM variant. In addition, they were unable to clear rapidly a P. c. chabaudi AS or P. v. lentum DS challenge. Both the multiplication and virulence of P. berghei ANKA were enhanced. These findings demonstrate that resolution of the primary acute parasitaemia in P. c. chabaudi AS- and P. y. yoelii A-infected mice is predominantly mediated by species- and strain-specific mechanisms.  相似文献   
3.
Summary A recently described separation technique consisting of a combination of counterflow centrifugation and subsequent density (Percoll) scparation was tested for its ability to enrich red cell populations with young cells in comparison to either separation technique alone. The relative age of every fraction was determined by HbAlc measurements, resulting in the lowest HbAlc for the combination method. Conventional reticulocyte counting and floweytometric counting with thiazole orange indicated that in the youngest fractions the combination method showed the highest reticulocyte counts. There was a good correlation between manual and flowcytometric counting results. Radio-iron studies showed a two-fold enrichment with young cells in the fraction with the lowest HbAIc acquired by the combination technique in comparison to the other two methods. Cytometric measurements showed that the fractions with the lowest HbAlc were the ones with the highest MCV and MCH and the lowest MCHC. Besides loss of their RNA-material, young cells already seem to loose water and haemoglobin like older cells, resulting in a decrease of MCV and MCH and in increase in MCHC. It is concluded that combining counterflow centrifugation with subsequent density fractionation results in superior enrichment with young cells in comparison to the results of each method alone.  相似文献   
4.
The effect of rosette formation on the multiplication in vitro of Plasmodium falciparum was studied in order to establish whether rosetting acts as a major virulence factor in the pathogenesis of severe malaria by facilitating invasion of uninfected red cells. Invasion rates for rosetting (R+) and non-rosetting (R) parasites selected from the same clone, PA1, of P. falciparum were similar over a range of starting parasite concentrations when assayed in both static cultures and conditions of shear stress comparable with microvascular flow. However, incubation of both R+ and R parasites under simulated conditions of flow led to decreased invasion and fewer multiply-infected red cells as we have previously observed. Studies using fluorescently labelled red cells or reticulocytes demonstrated that rosetting did not alter the rates of invasion or target merozoites into the uninfected cells comprising a rosette. Preferential invasion of reticulocytes occurred regardless of rosetting or conditions of flow. Although the role of rosetting in the pathogenesis of malaria might relate to microvascular obstruction or perhaps the restriction of phagocytosis, our data suggest that rosetting does not play a role in the invasion or targeting of parasites into uninfected cells, eliminating this mechanism to explain the association of virulence with the rosetting parasite phenotype.  相似文献   
5.
Anemia is a major health burden worldwide and affects approximately one‐third of world's population. It is not a diagnosis; it is a manifestation of an underlying pathophysiology leading to either decreased hemoglobin (Hb), hematocrit (Hct), or red blood cells (RBCs). Iron deficiency anemia is still the most common cause of anemia worldwide. The symptoms are usually due to the underlying compensatory responses to decrease in oxygen delivery to the tissues. Laboratory investigation should start with complete blood count (CBC), reticulocyte count (RC), and peripheral smear evaluation. Further testing depends on these indices, that is, iron parameters and hemoglobinopathies/thalassemia evaluation in microcytic hypochromic anemia, vitamin B12, and folic acid level in macrocytic anemia. Increased RC denotes adequate bone marrow response and points toward hemolytic process and vice versa. Anemia diagnosis can be complex and confusing for the practicing physician. This review tries to give a practical simplistic approach to the diagnosis, focusing mainly on the basic parameters, that is, CBC, RC, and peripheral smear etc. Moreover, we have also tried to provide an update on the pyruvate kinase deficiency, as there has been recent exciting development in the management of these patients.  相似文献   
6.
The Athlete Biological Passport (ABP) is principally founded on monitoring an athlete's biological variables over time, to identify abnormal biases on a longitudinal basis. Several factors are known to influence the results of these markers. However, the manner in which the altitude factor is taken into account still needs to be standardized. Causal relationships between haematological variables should be correctly integrated into ABP software. In particular, modifications of haematological parameters during and after exposure to different altitudes/hypoxic protocols need to be properly included within detection models. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
7.
Erythrocyte-based micronucleus tests have traditionally analyzed bone marrow because splenic filtration in most species removes micronucleated cells from peripheral blood. We have evaluated a flow cytometric method for monitoring micronucleated reticulocyte frequencies (%MN-RET) in the peripheral blood of beagle dogs treated with cyclophosphamide (CP) and have found that analysis of micronucleated reticulocytes (MN-RETs) in peripheral blood is a suitable surrogate for bone marrow analysis. The three-color flow cytometric method uses anti-CD71 labeling to identify reticulocytes and Plasmodium berghei-containing erythrocytes as a calibration standard. The spontaneous %MN-RET determined by flow cytometry was 0.31 +/- 0.09% (n = 22) for peripheral blood, compared with 0.38 +/- 0.13% (SD, n = 12) for bone marrow, and 0.27 +/- 0.08% (n = 12) for peripheral blood by microscopic scoring with acridine orange staining. The kinetics of appearance and disappearance of MN-RETs in blood were determined by collecting daily samples after iv treatment with CP. The maximum frequency occurred approximately 48 h after dosing. Frequencies of MN-RETs in peripheral blood at steady state following daily CP treatment were 55-68% of corresponding bone marrow values assessed by microscopy and 55-112% as assessed by flow cytometry. This difference is presumably due to splenic removal, which appears slightly less stringent than that previously reported for CP-treated Sprague-Dawley rats. Responses in bone marrow and peripheral blood were highly correlated and similar to or greater than those reported in mice and rats at equitoxic doses.  相似文献   
8.
ABSTRACT. A retrospective analysis of 18 patients with idiopathic myelofibrosis (IMF) suggested that IMF is adequately staged by combining haemoglobin value and reticulocyte count. Four stages were recognized. All deaths occurred in late stage. The stages appeared to reflect a sequential course of the disease. The present staging system adequately identified patients at high risk. However, the rate of disease progress varied greatly. It is therefore suggested that the rate of disease progress should also be considered when an individual patient is evaluated.  相似文献   
9.
Recent studies indicate that the Pig-a assay is a promising tool for evaluating in vivo mutagenicity. We have developed novel rat Pig-a assays that facilitate measuring mutant frequencies in two early arising populations of blood cells, bone marrow erythroids (BMEs) and peripheral blood (PB) reticulocytes (RETs). In these assays, bone marrow cells of erythroid origin and PB red blood cells (RBCs) were identified using an antibody against rat erythroid-specific marker HIS49. In addition, RETs were selectivity enriched from PB using magnetic separation of cells positive for CD71, a transferrin receptor expressed on the surface of BMEs and RETs, but not on the surface of mature RBCs. With magnetic enrichment, more than 1 x 10(6) CD71-positive RETs could be evaluated by flow cytometry for Pig-a mutant frequency within 5 to 8 min. CD59-deficient RET and BME frequencies of more than 100 x 10(-6) and 80 x 10(-6) were detected 1 week after treating rats with 40 mg/kg N-ethyl-N-nitrosourea; by comparison, the frequency of CD59-deficient total RBCs in these rats was 13.2 x 10(-6). The frequency of spontaneous Pig-a mutant RETs and BMEs was less than 5 x 10(-6) and 15 x 10(-6), respectively. Since approximately 98% of nucleated cells in the BME fraction were erythroblasts, it should be possible to use BMEs to determine the spectrum of CD59-deficient Pig-a mutations in cells of erythroid lineage. Conducting concurrent Pig-a assays on RETs and BMEs may be useful for evaluating the in vivo mutagenicity of chemicals, especially when prolonged mutant manifestation is not feasible or when the confirmation of mutation induction is necessary.  相似文献   
10.
目的探讨网织红细胞低荧光强度网织红细胞(LFR)、中荧光强度网织红细胞(MFR)、高荧光强度网织红细胞(HFR)三分群参数在珠蛋白生成障碍性贫血(珠贫)中的变化。方法用Sysmex XE-2100全自动血球计数仪检测α珠贫与β珠贫的网织红细胞三参数,进行珠贫与正常对照组比较,不同程度珠贫组间的比较。结果珠贫患者网织红细胞三分群与正常人比较,α珠贫与β珠贫比较,男女β珠贫非贫血组、轻度贫血组与中重度贫血组比较,女性β珠贫非贫血组与轻度贫血组比较,差异有显著性(P<0.05)。结论珠贫患者三分群与贫血程度有关,LFR随珠贫患者贫血程度降低而降低,MFR、HFR随珠贫患者贫血程度降低而增高。故网织红细胞分群三参数应用于珠贫患者检查,观察其造血功能有着重要的临床意义。  相似文献   
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