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61.
无机银抗菌剂及其塑料制品的抗菌效果和毒性   总被引:3,自引:4,他引:3  
为了解含银6%(g/g)的无机银抗菌剂的抗菌与破坏HBsAg效果及毒性,进行了纸片抑菌环测定、载体定性HBsAg试验与毒性试验。结果,该抗菌剂加水稀释20、200、400倍的混悬液所染滤纸,分别对白色念珠菌、金黄色葡萄球菌、大肠杆菌有抑菌效果;含该剂0.5%(g/g)的塑料洗衣球对大肠杆菌作用 5min,有抑菌作用;以该剂10倍稀释的悬液作用24h,才可破坏不锈钢片表面HBsAg抗原性。该抗菌剂对雌、雄小鼠经口LD50>5000mg/kg,对兔皮肤一次性刺激积分为0,微核试验阴性。  相似文献   
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Primary immune thrombocytopenia (ITP) of childhood is an autoimmune disease characterized by abnormally increased destruction of platelets and decreased megakaryopoiesis. Stromal‐derived factor‐1 (SDF‐1) plays a role in megakaryopoiesis and may be involved in the pathogenesis of ITP. Five single nucleotide polymorphisms (SNPs) of the SDF‐1 gene, including rs1801157, rs2839693, rs2297630, rs1065297, and rs266085, were assessed in 100 children with ITP and 126 healthy controls. The genotypes were analyzed by tetra ARMS polymerase chain reaction and confirmed by direct sequencing. Compared with controls, the rs2839693 A/A and rs266085 C/T genotypes were decreased in ITP patients (P = 0.004 and 0.007, respectively). The odds ratios of the latter genotypes were 0.48, 95% CI 0.28–0.82. Further analysis of the relationship between SDF‐1 polymorphisms and clinical features showed that rs2297630 A/G was associated with protection from chronicity (P = 0.002; OR, 0.07; 95% CI, 0.01–0.61) and steroid dependence (P = 0.007; OR, 0.10; 95% CI, 0.01–0.84) in ITP patients. However, rs266085 genotype C/C was associated with risk of steroid dependence (P = 0.012, OR 3.87, 95% CI 1.27–11.77). The findings of this study suggest that SDF‐1 gene variations may be associated with the occurrence and prognosis of childhood ITP.  相似文献   
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Background: Central venous access systems are frequently used for delivery of medications; however, few studies have compared surgical and postoperative complications of right versus left access via the subclavian vein (SCV). The aim of this study was to compare the surgical and postoperative complications associated with Port-A-Cath system insertion via the right and left SCV. Methods: The medical records of patients who received Port-A-Cath insertion via the SCV for parenteral chemotherapy between August 2004 and July 2008 were reviewed. The incidence of surgical and postoperative complications was compared between patients who received right- versus left-SCV Port-A-Cath insertion. Results: A total of 1,848 patients were included in the study. Right-SCV catheterization was attempted in 1,029 (55.7%) patients and was successful in 866 (84.2%). Left-SCV catheterization was attempted in 819 (44.3%) patients and was successful in 651 (79.5%). The mean length of postoperative follow-up was 417.3 ± 401.3 and 396.7 ± 379.9 days for the right- and left-SCV groups, respectively. The incidence of SCV puncture failure was significantly lower in the right-SCV group (12.3%) compared with the left-SCV group (16.8%, p = 0.006). The incidence of catheter knotting at the ipsilateral brachiocephalic vein was also significantly lower in the right-SCV group (0.0%) compared with the left-SCV group (0.5%, p = 0.038), as was the incidence of catheter occlusion (1.0% for right SCV vs. 3.5% for left SCV, p = 0.001). Conclusion: These findings suggest that the right-SCV approach is superior to the left-SCV approach for Port-A-Cath insertion.  相似文献   
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In recent years, a constant growth of knowledge and clinical applications of stem cells have been observed. Mesenchymal stromal cells, also described as mesenchymal stem cells (MSCs) represent a particular cell type for research and therapy because of their ability to differentiate into mesodermal lineage cells. The most investigated source of MSCs is bone marrow (BM). Yet, collection of BM is an invasive procedure associated with significant discomfort to the patient. The procedure results in a relatively low number of these cells, which can decrease with donor's age. Therefore, it seems to be very important to find other sources of mesenchymal stem cells nowadays. A human placenta, which is routinely discarded postpartum, in spite of its natural aging process, is still a rich source of stem cells capable to proliferate and in vitro differentiate in many directions. Besides homing and differentiation in the area of injury, MSCs there elicit strong paracrine effects stimulating the processes of repair. In this review, we focus on the biology, characteristics and potential clinical applications of cells derived from human fetal membranes: amnion and chorion.  相似文献   
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Protein tyrosine phosphatase sigma (PTPσ) is a promising target for the development of therapeutics for the neurological diseases caused by the impaired recovery from neural injury. Based on the virtual screening with the scoring function involving a new accurate solvation energy term and in vitro enzyme assay, we identified seven competitive PTPσ inhibitors with the associated IC50 values ranging from 5 to 11 μM. These inhibitors are structurally diverse and expected to have desirable physicochemical properties as a drug candidate. Therefore, they deserve consideration for further development by structure–activity relationship studies to optimize the inhibitory activities against the neurological diseases. Structural features relevant to the stabilization of the newly identified inhibitors in the active site of PTPσ are discussed in detail.  相似文献   
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