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51.
OBJECTIVE: To determine the most frequent clinical causes of a prolonged activated partial thromboplastin time (APTT) result, and to determine whether a new heparin-removal device (the Hepchek, Pall Biomedical, Glen Cove, NY 11542) is capable of efficiently detecting the causes of these values. DESIGN: A combination of chart review and laboratory testing comparing the criterion standard--the heparin chromogenic substrate assay--with the Hepchek. Laboratory investigations were blinded and controlled. SETTING: Inpatient, acute-care hospital. PATIENTS: A total of 1,000 hospital patients with a variety of hemostatic disorders. MAIN OUTCOME MEASURE: The extent to which the Hepchek accurately identified the etiology of a prolonged APTT result. RESULTS: The APTT was prolonged in 25.2% of samples. The presence of heparin in the sample was confirmed by chromogenic assay or by using the Hepchek heparin-removal filter. The presence of heparin was confirmed in 12.8% of all samples and in more than 50% of all abnormal samples. The cause of the abnormal APTT was often unappreciated by the clinician. Bayesian analysis of the Hepchek's ability to diagnose heparin correctly as the cause of the abnormal APTT showed a sensitivity of 100% and specificity of 99.9%. CONCLUSION: Use of the Hepchek in the routine clinical laboratory is an efficient and rapid method of detecting heparin as a cause of isolated prolonged APTT results, and should reduce demands for unwarranted coagulation analyses and inappropriate treatment with blood products.  相似文献   
52.
53.
【目的】探讨地塞米松的用药方式对孕妇糖代谢的影响。【方法】对 1999年 9月至 2 0 0 1年 1月在本院住院的15 0名不同用药方式使用地塞米松促胎儿肺成熟的孕妇进行研究 ,在用药前及用药后 18~ 2 4h抽取肘前静脉血查空腹血糖、血浆C肽 ,糖负荷后 2h血糖、血浆C肽。【结果】使用地塞米松后 ,空腹血糖值、糖负荷后 2h血糖值、空腹C肽及糖负荷后 2hC肽值较用药前高 ;用药方式对母体空腹血糖值和空腹C肽值的影响差异无统计学意义 (P >0 0 5 ) ,对母体糖负荷后 2h血糖值和糖负荷后 2hC肽值的影响差异有统计学意义 (P <0 0 5 ) ;不同糖代谢状态的受试者使用地塞米松后 ,空腹C肽值、糖负荷后 2hC肽值的改变差异有统计学意义 (P <0 0 5 )。【结论】孕妇使用地塞米松促胎儿肺成熟对母体的糖代谢均有一定程度的影响 ,用药过程中和用药后需严密监测母体血糖和胎儿宫内状况  相似文献   
54.
Previously, we prepared two different monoclonal antibodies (mAbs) against human 4-1BB (CD137): an agonistic mAb BBK-1 and an antagonistic mAb BBK-2. In this paper, we describe the molecular cloning of these two mAbs and present comparisons of their amino acid sequences. cDNAs encoding the heavy (H) and light (L) chains of the two mAbs were cloned by screening of cDNA libraries constructed from hybridomas secreting these mAbs. Comparisons of amino acid sequences of the two mAbs showed that, while the constant regions of the H and L chains were identical between the two mAbs, the variable region showed 45% identity in H chains and 48% identity in L chains. This suggests that these two mAbs recognize different epitopes of 4-1BB and may have different effects on the activity of 4-1BB.  相似文献   
55.
儿童输液中心患儿家属心理需求调查分析   总被引:14,自引:0,他引:14  
目的 探讨儿童输液中心患儿家属的心理需求,方法 采用问卷调查的方法。结果 家属对患儿所患疾病知识的了解需求十分强烈,占100%,技术服务需求占93%,65%的家属担心输液时出现不良反应,75%的要求发放保健知识手册,根据上述需求,采取相应的护理措施,家属的满意度达到了99%。结论 通过对家属心理需求调查分析及采取相应措施,能提高服务质量。  相似文献   
56.
bFGF对人毛囊黑素细胞增殖、活化和黑素合成作用的研究   总被引:3,自引:0,他引:3  
目的 研究碱性成纤维细胞生长因子 (bFGF)对人毛囊黑素细胞 (Hairfolloclemelanocyte ,HFM )增殖活化和黑素合成的影响。方法 体外培养正常人HFM ,观察不同浓度bFGF(0 3~ 1 2ng ml)对HFM形态、增殖、酪氨酸酶活性和黑素含量的影响。结果 bFGF处理HFM 7d后 ,HFM树突增多延长 ,酪氨酸酶活性和黑素含量增加显著高于对照组 (P <0 0 1) ,以 0 6ng ml组为著。结论 bFGF能诱导HFM增殖、酪氨酸酶活性和黑素合成增加  相似文献   
57.
AIM: To report the clinical and oncological data of patients operated on for rectal cancers 3-5 cm from the AV over a 10 year period, including the Sphincter preservation (SP) rate. METHODS: We reviewed medical records of 304 patients with rectal cancers 3-5 cm from the AV who underwent surgical resection from January 1991 through December 2000. The 10 years were divided into three periods based on the introduction of new surgical techniques, specifically, ultralow anterior resection (ULAR) with double stapling in March 1994 and ULAR with coloanal anastomosis in April 1997. The rates of SP, complications and patient survival during these periods were compared. RESULTS: The SP rate increased significantly over the 10 years, from 16.4% in period I (January 1991-February 1994), to 53.0% in period II (March 1994-March 1997), to 86.5% in period III (April 1997-December 2000) (p<0.001). Over time, the age of the patients increased (p=0.004), the length of the distal resection margin became shorter (p=0.005), and the rate of lymph node metastasis increased (p=0.016). The factors significantly influencing SP were the period (p<0.001) and the distance from the AV (p<0.001). Over time, morbidity did not increase, and overall and disease free survival rates did not decrease. In contrast, the overall survival of N2 cases significantly increased over time (p=0.0492). CONCLUSION: Over 10 years, the SP rate in rectal cancers 3-5 cm from the AV was significantly increased by the introduction of the double stapling and coloanal anastomosis techniques. These surgical methods, however, had no effect on morbidity, disease free survival and overall survival rates.  相似文献   
58.
Nerve growth factor (NGF) gene expression in central nervous system (CNS) glia appears to be associated with active glial growth. To study the underlying molecular mechanisms, we examined the effects of a number of growth-related factors on NGF mRNA expression in glial cultures. Our results suggest that glial membrane interaction, as a consequence of growth, actively inhibits NGF gene expression in CNS glia.  相似文献   
59.
Critical size defect in the canine mandible.   总被引:3,自引:0,他引:3  
OBJECTIVE: The purpose of this study was to determine the minimum size defect in a canine mandible that would not spontaneously heal during the dog's natural life (the critical size defect). STUDY DESIGN: Sixteen adult female mongrel dogs underwent continuity resection on both sides of the mandible to create bilateral defects. In 8 dogs, mandibular defects ranging from 5 to 20 mm were created with periosteal resection. In the other 8 dogs, mandibular defects ranging from 30 to 60 mm were created preserving the periosteum. The dogs were then killed at 6 months and the defects examined using radiographs and histologic analysis. RESULTS: When the periosteum was removed, mandibular defects greater than 15 mm failed to heal across the entire defect. However, when the periosteum was preserved, mandibular defects needed to be greater than 50 mm in order to fail to heal. CONCLUSION: The critical size defect in a canine mandible model is 15 mm when the periosteum is removed and 50 mm when the periosteum is preserved.  相似文献   
60.
OBJECTIVE: This article 1) provides an overview of formal Health Sciences Teaching Scholars Programs as presented in medical education literature and 2) presents information about an innovative multidiscipline Teaching Scholars Program. METHOD: Health Sciences Teaching Scholars Programs and similar programs were reviewed in the medical education literature to identify similar and dissimilar characteristics. The WVU Teaching Scholars Program highlighted in this article is presented with a discussion of goals, objectives, target audiences, course length, session frequency, program topics, learning methods, and assessments of the programs. A summary of the WVU Teaching Scholars Program and two Teaching Scholars Programs at McGill University and the University of Toronto were presented at the Association for American Medical Colleges (AAMC) annual meeting in 2006 for input from the general medical education audience. RESULTS: Comparisons of Health Sciences Teaching Scholars Programs reveal that successful programs are uniquely shaped by their educational environments. Scholars report that they value learning new teaching methods and improving their educational careers. CONCLUSION: Teaching Scholars Programs are valuable for the development of enhancing both teaching and scholarship in Health Sciences Programs and must adapt to the uniqueness of their respective educational environments and must continue to nurture scholars beyond graduation.  相似文献   
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