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41.
目的 探讨能否直接利用肿瘤细胞膜进行表皮生长因子受体 (Epidermalgrowthfactorreceptor,EGFR)催化活性检测。方法 首先筛选出EGFR基因表达水平相对较高的细胞株MDA MB 2 31,通过差速离心制备细胞膜 ,采用Westernblotting检测EGFR催化磷酸化的程度。结果 底物被磷酸化 ,加入特异性拮抗剂AG14 78后 ,磷酸化被抑制。结论 利用肿瘤细胞膜检测EGFR活性的设想是成立的 ,并且其方法简便、经济。 相似文献
42.
I. M. Libermann H. García Pierce M. Labat J. Seigal 《Pflügers Archiv : European journal of physiology》1971,330(1):51-60
Summary Dogs were water depleted 2% of their body weight by the intraperitoneal injection of a hyperosmotic solution of saline and glucose (550 mOsm/l). During a 3-h experiment these water-depleted (WD) animals showed a significant decrease in blood pH, base excess (BE) and plasma bicarbonate (Bicp) and an increase in both hematocrit (Ht) and blood buffer capacity (BBC). These changes were quantitatively time-dependent. The rate change of pH, BE, and Bicp were –0.072 units h–1, –4.7 mEq/l h–1, and 2.9 mEq/l h–1, respectively. As control dogs showed no significant time-dependent changes in their blood acid-base status, the observed modifications in the experimental dogs were ascribed to water depletion. Increased endogenous acid production related to tissue hypoxia is suggested to be the mechanism that could explain the increased fixed acid accumulation observed in the water-depleted animals. 相似文献
43.
Acute hypervolemia does not improve arterial oxygenation in maximally exercising thoroughbred horses
Recently, it was reported that acute hypervolemia improves arterial oxygen tension in human athletes known to experience exercise-induced arterial hypoxemia. Since exercise-induced arterial hypoxemia is routinely observed in racehorses and is known to limit performance, we examined whether pre-exercise induction of acute hypervolemia would similarly benefit arterial oxygenation in maximally exercising thoroughbred horses. Two sets of experiments, namely, placebo [intravenous (IV) physiological saline] and acute hypervolemia (IV 7.2% NaCl, causing an 18.2% expansion of plasma volume) studies were carried out in random order on 13 healthy, exercise-trained thoroughbred horses, 7 days apart. An incremental exercise protocol leading to 120 s of galloping at 14 m s–1 on a 3.5% uphill incline was used. Galloping at this workload elicited maximal heart rate and induced pulmonary hemorrhage in all horses in both treatments. In the placebo study, arterial oxygen tension decreased to 76.1 (2) mmHg (P<0.0001) at 30 s of maximal exertion, but further significant changes did not occur as exercise duration increased to 120 s [arterial oxygen tension 72.4 (2) mmHg]. A significant arterial hypoxemia also developed in galloping horses in the acute hypervolemia study [arterial oxygen tension at 30 and 120 s was 76.7 (1.7) and 71.9 (1.6) mmHg, respectively], but significant differences between treatments could not be demonstrated. In both treatments, a similar desaturation of arterial hemoglobin was also observed at 30 s of maximal exercise, which intensified with increasing exercise duration as hyperthermia, acidosis and hypercapnia intensified. Thus, acute expansion of plasma volume did not benefit arterial oxygenation in maximally exercising thoroughbred horses. 相似文献
44.
Plasma fibronectin in psoriatic arthritis subgroups 总被引:1,自引:0,他引:1
Summary Plasma from 38 patients suffering from one of the five broad clinical subgroups of Psoriatic Arthritis (PA) were studied for soluble plasma Fibronectin (pFn). The mean total concentration of pFn was 453.03g/ml ± 142.83 SD, with a significant statistical difference (p<0.01) versus a healthy control group matched with respect to sex and age. In order to evaluate the biological role that pFn might play in this pathological condition, observed concentrations were correlated with the degree and duration of the psoriasis and arthritis. In addition, pFn was correlated to some biohumoral parameters that are modified during inflammatory processes (ESR, CRP, sCu, sFe, Hb) and to uric acid levels. Tissue typing (HLA) was done where possible. From our observations, we suggest that pFn most likely is not an acute phase protein and rather than having specificity for a particular disease, might, in widespread and severe cases be,a general and useful marker of the connective-tissue organizing and repairing response, following its injury. 相似文献
45.
46.
Asiye İzem Sandal Hatice Şenlikci Merve Yılmazer Burcu Kartal Bedia Palabıyık Özen Banu Özdaş 《Andrologia》2021,53(5):e14032
The aim of the study was to investigate the efficiency of ram seminal plasma and fetal calf serum on freezing of buck semen. Twenty ejaculates were collected using an electro-ejaculator and split into six groups. While FCS additive was not used in A1, A2 and A3 groups, 10% FCS was added to B1, B2 and B3 groups. These groups were then edited according to whether the buck or ram SP was involved. The design of the groups was done as follows: Group A1 (control 1), group A2 without buck SP, group A3 containing ram SP instead of buck SP. Groups B1 (control 2), B2 and B3 were the FCS added forms of these groups. Progressive sperm motility percentages in Group A1 and Group B2 were found to be higher when compared to the lowest Group B3. There were no significant differences between the groups in neither the levels of reactive oxygen species nor the enzyme and glutathione activities. In conclusion, the lack of statistical difference between the groups suggested that despite the supplements used but only when the buck spermatozoa structure was healthy, the cell could preserve acrosome, DNA and the integrity of membrane. 相似文献
47.
《Burns : journal of the International Society for Burn Injuries》2021,47(6):1342-1351
Hypertrophic burn scars remain a significant burden for patients and a challenge for clinicians.The aimAssessement of the efficacy of combined Pulsed Dye Laser and Ablative Fractional CO2 Laser therapy on hyperthophic scars and correlation with plasma levels of MMP-2, TIMP-1 and alpha-1 type I collagen.Patients and methodsTwenty five pediatric subjects were enrolled into the study. Control group consisted of age-matched subjects admitted for surgical repair of inguinal hernia. For the assessment of the results of laser treatment we used the Vancouver scar scale (VSS), and Patient-Observer Scar Assessment Scale (POSAS). We also correlated clinical results with plasma levels of MMP-2, TIMP-1 and alpha-1 type I collagen.ResultsAll subjects reported the laser treatment resulted in improvement and were somewhat satisfied or very satisfied with their experience. No adverse events were reported. The levels of MMP-2, TIMP-1 and alpha-1 type I collagen in our patients with scars before laser threatment were higher in comparison to controls. We also found statistically significant decrease in the levels of MMP-2, TIMP-1 and alpha-1 type I collagen after laser treatment of burn scarsConclusionsOur study clearly shows that combined CO2-AFL treatment for burn scars improve texture, colour, function and alleviate pruritus. We believe that decrease in the levels of MMP-2, TIMP-1 and alpha-1 type I collagen after laser treatment of burn scars, reflects reduced dynamic of scar. 相似文献
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49.
对36例多发性骨髓瘤(MM)患者骨髓涂片,行酸性磷酸酶(ACP)染色。结果发现MM组的骨髓浆细胞ACP积分明显高于对照组。MM组初诊时、缓解期和复发期46人次检测结果表明,成MM病程中ACP积分病情变化而变化,缓解期的较初诊时降低,复发期的又复增高。这种变化有时较骨髓浆细胞比例的变化与病情的关系更为密切,提示ACP积分可作为MM病情监测的指标。 相似文献
50.
Senescence and the retinal pigment epithelium: alterations in basal plasma membrane morphology 总被引:1,自引:0,他引:1
Marked age-related changes in the morphology of retinal pigment epithelial (RPE) cell basal infoldings were found in pigmented rats. Quantitative morphometric analysis revealed that during senescence the amount of basal plasma membrane per unit RPE length increased substantially, the regional distribution of the basal infoldings along the RPE became more irregular, and the average depth of penetration of the basal infoldings into the RPE increased dramatically. The crucial role of the RPE in maintaining retinal integrity suggests that the observed changes in RPE morphology may be involved in the development of senile retinopathies which occur in a variety of species, including man. 相似文献