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71.
采用化学共沉淀法制备锑掺杂二氧化锡(ATO)超细导电粉体,研究了反应温度,滴定终点pH值,掺锑量及锻炼温度对粉体导电性的影响,并对实验结果进行了讨论。  相似文献   
72.
探讨了以H2SO4和CH2OHCH2Cl为酸解介质时,氯化法金红石型钛白粉表面包铝的行为及形态特征。利用正交实验研究了包膜过程中,熟化pH、熟化时间以及温度对包铝钛白粉白度的影响。氯化法金红石型钛白粉浆在pH为10时,Zeta电位最大,在水中达到最佳分散,利用H2OHCH2Cl作为酸解介质时,浆液中的均相成核得到显著抑制,钛白粉表面的包膜质量得到明显改善。以稀硫酸作为酸解介质时,随熟化温度升高和熟化时间的延长,钛白粉包覆效果明显改善,白度值明显升高。  相似文献   
73.
HEALTH CARE REPORT CARDS INVOLVE COMPARISONS of health care systems, hospitals or clinicians on performance measures. They are going to be an important feature of medical care in Canada in the new millennium as patients demand more information about their medical care. Although many clinicians are aware of this growing trend, they may not be prepared for all of its implications. In this article, we provide some historical background on health care report cards and describe a number of strategies to help clinicians survive and thrive in the report card era. We offer a number of tips ranging from knowing your outcomes first to proactively getting involved in developing report cards.  相似文献   
74.
尿液结合性胆红素的纯化   总被引:2,自引:1,他引:1  
Y Guo  M Chen  Y Tu  H Luo  S Li  D Yan  M Niu 《华西医科大学学报》2001,32(4):579-581
OBJECTIVES: To develop a simple, practical method with fine yield and purity for separating conjugated bilirubin(Bc) from a sustainable and facile material in order that it could serve as a calibrator for total and direct bilirubin determination. METHODS: Isolating Bc from urine of patients with obstructive jaundice by CHCl3: CH3CH2OH(1:1, V/V) followed by CNBr activated Sepharose 4B-HAS affinity chromatography, we analyzed the products by the use of Doumas J-G diazo method and HPLC, respectively. RESULTS: Determined by J-G diazo method, the crude product extracted by CHCl3: CH3CH2OH(1:1, V/V) yields 90.2 +/- 5.4%(n = 3) of urine Bc, the ratio of Bc to total dry weight being 67.9 +/- 6.4%(n = 3). The final product purified by affinity chromatography with the ratio of separation of 1.5, 1.737 and analyzed by HPLC has the yield of 46.9% and purity of 94.7%(BDG of 76.2%, BMG of 18.5%). CONCLUSION: The above data demonstrate that urine conjugated bilirubin can be successfully purified by CHCl3: CH3CH2OH extraction followed by Sephrose-HSA affinity chromatography with sufficient purity and output.  相似文献   
75.
目的 探索一种来源方便 ,具有延续性 ,利于胆红素测定校准物或质控物制备 ,且方法简便、实用、产率和纯度可靠的结合性胆红素 (Bc)纯化方法。方法 应用 CHCl3 ∶ CH3 CH2 OH(1∶ 1,V/V)萃取与 CNBractivated Sepharose4B- HSA亲和层析相结合的方法对胆道梗阻性高胆红素尿液进行分离纯化 ,并以 Doum as J- G法和 HPL C分析产品。结果 由 CHCl3 ∶ CH3 CH2 OH(1∶ 1,V/V)萃取所得的粗纯品经 J- G法检测产率为 90 .2±5 .4% (n=3) ,胆红素含量占总干重的 6 7.9± 6 .4% (n=3)。亲和层析的洗脱峰间的分离度为 1.5、1.737。层析后再萃取所得精纯品经 HPL C分析 ,产率为 46 .9% ,纯度 94.7% ,其中 BDG76 .2 % ,BMG18.5 %。结论 采用有机物萃取和 CNBr activated Sepharose4B- HSA亲和层析相结合的方法纯化结合性胆红素 (BMG& BDG)具有很好的可靠性和可行性  相似文献   
76.
BackgroundFamily history of prostate cancer (PCa) is a well-known risk factor, and both common and rare genetic variants are associated with the disease.ObjectiveTo detect new genetic variants associated with PCa, capitalizing on the role of family history and more aggressive PCa.Design, setting, and participantsA two-stage design was used. In stage one, whole-exome sequencing was used to identify potential risk alleles among affected men with a strong family history of disease or with more aggressive disease (491 cases and 429 controls). Aggressive disease was based on a sum of scores for Gleason score, node status, metastasis, tumor stage, prostate-specific antigen at diagnosis, systemic recurrence, and time to PCa death. Genes identified in stage one were screened in stage two using a custom-capture design in an independent set of 2917 cases and 1899 controls.Outcome measurements and statistical analysisFrequencies of genetic variants (singly or jointly in a gene) were compared between cases and controls.Results and limitationsEleven genes previously reported to be associated with PCa were detected (ATM, BRCA2, HOXB13, FAM111A, EMSY, HNF1B, KLK3, MSMB, PCAT1, PRSS3, and TERT), as well as an additional 10 novel genes (PABPC1, QK1, FAM114A1, MUC6, MYCBP2, RAPGEF4, RNASEH2B, ULK4, XPO7, and THAP3). Of these 10 novel genes, all but PABPC1 and ULK4 were primarily associated with the risk of aggressive PCa.ConclusionsOur approach demonstrates the advantage of gene sequencing in the search for genetic variants associated with PCa and the benefits of sampling patients with a strong family history of disease or an aggressive form of disease.Patient summaryMultiple genes are associated with prostate cancer (PCa) among men with a strong family history of this disease or among men with an aggressive form of PCa.  相似文献   
77.
BackgroundDuctal prostate adenocarcinoma (DAC) is a rare, aggressive, histologic variant of prostate cancer that is treated with conventional therapies, similar to high-risk prostate adenocarcinoma (PAC).ObjectiveTo assess the outcomes of men undergoing definitive therapy for DAC or high-risk PAC and to explore the effects of androgen deprivation therapy (ADT) in improving the outcomes of DAC.Design, setting, and participantsA single-center retrospective review of all patients with cT1–4/N0–1 DAC from 2005 to 2018 was performed. Those undergoing radical prostatectomy (RP) or radiotherapy (RTx) for DAC were compared with cohorts of high-risk PAC patients.Outcome measurements and statistical analysisMetastasis-free survival (MFS) and overall survival (OS) rates were analyzed using Kaplan-Meier and Cox regression models.Results and limitationsA total of 228 men with DAC were identified; 163 underwent RP, 34 underwent RTx, and 31 had neoadjuvant therapy prior to RP. In this study, 163 DAC patients and 155 PAC patients undergoing RP were compared. Similarly, 34 DAC patients and 74 PAC patients undergoing RTx were compared. DAC patients undergoing RP or RTx had worse 5-yr MFS (75% vs 95% and 62% vs 93%, respectively, p < 0.001) and 5-yr OS (88% vs 97% and 82% vs 100%, respectively, p < 0.05) compared with PAC patients. In the 76 men who received adjuvant/salvage ADT after RP, DAC also had worse MFS and OS than PAC (p < 0.01). A genomic analysis revealed that 10/11 (91%) DACs treated with ADT had intrinsic upregulation of androgen-resistant pathways. Further, none of the DAC patients (0/15) who received only neoadjuvant ADT prior to RP had any pathologic downgrading. The retrospective nature was a limitation.ConclusionsMen undergoing RP or RTx for DAC had worse outcomes than PAC patients, regardless of the treatment modality. Upregulation of several intrinsic resistance pathways in DAC rendered ADT less effective. Further evaluation of the underlying biology of DAC with clinical trials is needed.Patient summaryThis study demonstrated worse outcomes among patients with ductal adenocarcinoma of the prostate than among high-grade prostate adenocarcinoma patients, regardless of the treatment modality.  相似文献   
78.
Chen  Hongli  Tu  Mengru  Shi  Jia  Wang  Yunhao  Hou  Zhenhao  Wang  Jinhai 《Lasers in medical science》2021,36(3):555-562
Lasers in Medical Science - Delayed wound healing is one of the most challenging complications of diabetes mellitus (DM) in clinical medicine, and it is related to the excessive generation of...  相似文献   
79.
李嫒  涂素华 《护理学杂志》2021,36(10):107-109
阐述婴儿生物养育的概念、实施步骤、与传统哺乳姿势的区别、对母婴的影响,以期提高我国医务工作者对生物养育的认知、促进生物养育提供参考.  相似文献   
80.
目的 构建居家养老环境风险评估指标体系,为开展老年人居家环境风险评估提供测评工具.方法 采用文献研究法、焦点小组讨论法、德尔菲专家咨询法筛选评估指标,运用层次分析法确定指标权重,建立老年人居家养老环境风险评估体系.结果 2轮专家咨询问卷有效回收率分别为92.31%、86.11%,权威系数分别为0.878、0.892;Ⅰ级指标协调系数分别为0.276、0.291;最终构建的居家养老环境风险评估指标体系包括Ⅰ级指标9个和Ⅱ级指标43个,并确定各级指标权重.结论 居家养老环境风险评估体系被专家认可,评估指标体系的内容全面、权重合理,但需进一步在社区开展实证研究.  相似文献   
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