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21.
精准模拟肺癌发病病理过程的动物模型是促进肺癌基础和转化研究的关键,而目前常用的皮下移植瘤模型难以体现肺脏的基质环境特征。小动物活体成像技术可客观、动态地评价肺癌的肿瘤负荷变化及转移发生情况,在此基础上建立的肺癌原位移植瘤动物模型可解决以上难题,充分体现肺癌的发病学特征。而人源性肿瘤组织异种移植(patient derived tumor xenograft,PDTX)原位模型和类器官模型也可部分体现肿瘤微环境和肿瘤细胞的异质性,均已成为该领域的重要发展方向。  相似文献   
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为培养高素质输血医学专业人才,构建输血医学本科实习新模式。本研究自2013年从检验医学本科专业中招收输血医学定向实习生,从师资团队、轮转岗位、实习内容、综合素质等方面,建立有针对性的输血医学定向实习教学新模式。通过定向实习新模式的培养,输出了基础知识扎实、操作技能强、综合素质高的优秀输血医学专业人才。输血医学定向实习模式的建立有利于高素质输血人才的培养与输出,对输血医学教育的发展起到了积极的推动作用。  相似文献   
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ObjectivesThe aim of the present study is to evaluate the feasibility and safety of performing PNL under local anesthesia in a selected group of patients who are at high risk for general anesthesia.Patients and methodsForty seven patients underwent PNL under local anesthesia. There were 38 males and 9 females with a mean age of 62 years. All patients were at medical high-risk for general anesthesia, with an American Society of Anesthesiologists (ASA) score of 3. The indications for local anesthesia in this study were obstructed single functioning kidney with azotemia in 29 patients, hepatic insufficiency in 8 patients, cardiac problems in 7 patients and 3 patients had hepatocellular carcinoma. The mean stone size was 2.7 cm (range 2–3.1 cm). Local infiltration with 10–20 cc of 2% lidocaine at the site of puncture was used in all cases. Narcotics were given 30 min prior to the procedure and medazolam was given intraoperatively upon demand. Utrasound guided puncture was performed in all cases and tract dilatation was then done under fluoroscopy using high pressure balloon catheter in 35 and Alken's metal dilators in 12 cases. Stones were then retrieved after disintegration in the same cession in 33 patients, while the other 14 patients underwent staged PNL, where a 12 Fr. nephrostomy tube was placed in the first stage, followed by tract dilatation and stone retrieval one week later.ResultsOut of 47 patients included, 44 had successful PNL either one stage (30 patients) or two stages (14 patients). Only 3 patients could not tolerate pain and the procedure was terminated after placement of nephrostomy tube and stone retrieval was completed later under general anesthesia.ConclusionOur results demonstrated that PNL under local anesthesia with narcotics and sedatives seems to be a satisfying solution for the treatment of a selected group of patients with renal pelvic stones and who have high anesthetic risk. However, additional studies with different groups of patients are required to validate our results.  相似文献   
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Lee  SB; Rao  AK; Lee  KH; Yang  X; Bae  YS; Rhee  SG 《Blood》1996,88(5):1684-1691
Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function.  相似文献   
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Orstavik  KH; Kornstad  L; Reisner  H; Berg  K 《Blood》1989,73(4):990-993
A significant fraction (30%) of the genetically determined variance in plasma concentration of the von Willebrand factor antigen (vWf:Ag) has been shown to be related to ABH determinants. Individuals with blood group O, who have the highest amounts of blood group H substance, have the lowest concentration of vWf:Ag. The Lewis substances, Le(a) and Le(b), are biochemically closely related to the ABH substances as both can be produced from the same precursor substance. We studied the effect of the presence of the Lewis antigens on the plasma concentration of vWf:Ag and factor VIII antigen (VIII:Ag) in 323 individuals of different ABO groups from a series of twins and in 58 blood donors of blood group O. Among persons belonging to blood group O, those with the Le(a) antigen had a higher concentration of both vWf:Ag and VIII:Ag than individuals lacking Le(a). Le(a+b-) people are nonsecretors and Le(a-b+) people are secretors of ABH substance. Thus, the lowest concentration of vWf:Ag and VIII:Ag was found in group O secretors. The effect is most likely due to an effect of the secretor locus. This finding may be of importance for the detection of carriers of hemophilia A and for the diagnosis of type I von Willebrand disease.  相似文献   
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