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11.
静脉输液加药后的微粒变化   总被引:7,自引:1,他引:6  
本文对我院急诊病人常用的供静脉给药的22种药物、42组配伍情况,制成静脉加药输液,在超净工作台条件下,用KF—4型微粒计数器,测定了168次微粒数,结果显示输液加药后微粒虽有增加,但均在药典规定范围内。输液中加1种、2种、3种药物后所产生的微粒数分别为x_1=5.52(n_1=16);x_2=8.17(n_2=18)、x_3=10.25(n_3=8),经统计处理,三组间无显著差异(P<0.05)。本文对产生微粒的药物、注射器、操作环境等因素进行了分析。  相似文献   
12.
A case-control study to evaluate the efficacy of lung cancer screening conducted by us showed that lung cancer screening may reduce the mortality of the disease up to 28%. Assuming this efficacy is unbiased, and that the screening rate is 51.6%, which was observed in the control group in the above study, the number of lung cancer deaths prevented by screening in the study period was calculated to be 47 for males and females combined. In the same study population, screen-detected lung cancer patients (N = 207) in the same study period were followed and the 7-year survival rate (46.9%) was compared to the 5-year survival rate (11.3%) obtained by the Osaka Cancer Registry, in which screen-detected lung cancer patients were only 1.8%. The number of lung cancer deaths prevented by screening, estimated by the difference in the above two survival rates, was 74 (95% confidence interval; 55–93). The number of lung cancer deaths prevented by screening estimated from the case-control study was significantly lower than that estimated from the survival analysis. This indicates that the efficacy of lung cancer screening estimated by the case-control study was within the range that could be explained by the actual long-term survivors among the screen-detected patients in the study population.  相似文献   
13.
作者综述了10年来对Duchenne型肌营养不良症(DMD)的研究概况。主要包括①DMD的临床研究。②血清生化研究表明CK、LDH、Mb是诊断DMD病人和携带者的敏感指标。③心脏无创性检测和肌肉超微结构研究。④部分抗肌萎缩蛋白基因YAC物理图谱,精细限制酶图谱和缺失热区的核苷酸顺序分析,首次发现内含子中AT富集区的同源顺序与DMD断裂有关。⑤抗肌萎缩蛋白的缺失热区疏水肽段存在与否与DMD发病密切相关。  相似文献   
14.
Polysaccharidenucleicacidfractionofbacilluscalmetteguerin (BCG PSN ,SiqikangInjection)andthymopeptidesarenowtwowidelyusedimmunomod ulatorsinclinicalpractice .Theyareusuallyusedasanadjuvanttherapyforvirusinfection ,autoimmunediseasesandneoplasms ,whichhavebeenclinicallyprovedtobeeffective .Somereportsdemonstratedthattheybothcanstimulatetheproliferationanddif ferentiationofT lymphocytes.However ,theexactmechanismshavenotbeenelucidatedyet .InordertocomparetheirmodulatingmechanismsonT lympho c…  相似文献   
15.
Endoscopic ultrasound (EUS) is sensitive for staging gastrointestinal malignancies and pancreatic lesions. EUS‐fine‐needle aspiration (EUS‐FNA) offers a diagnostic accuracy of about 60–90% for pancreatic tumors and > 90% for lymph nodes. There are several limitations of EUS‐FNA including the need for on‐site cytopathology review. In addition, accuracy of cytologic review is hampered by the presence of blood, benign epithelial cells, desmoplasia, and well‐differentiated tumors. Furthermore, the small biopsy sample and destruction of tissue architecture limits the diagnostic sensitivity for GISTs and lymphomas. Many of these problems can be overcome with use of EUS trucut biopsy (TCB) needles. These large caliber, cutting needles acquire larger tissue samples allowing preservation of tissue architecture and histologic examination. Our recently described experience with EUS‐TCB initially in swine and later humans demonstrated the safety for acquiring histologic tissue representative of the target organs sampled enabling accurate diagnosis. These studies suggested greater diagnostic accuracy of EUS‐TCB for submucosal mass lesions and lymphoma and potentially the need for fewer needle passes for solid pancreatic neoplasms. In this paper we will review the current TCB literature, device design and technique, help troubleshoot potential problems, and offer opinion as to the utility and role of this new device.  相似文献   
16.
控制不同的反应条件,采用甲基丙烯酸、苯乙烯与环氧树脂在丙二醇丁醚/正丁醇溶剂中接枝共聚,合成了粒径在87~104nm范围的环氧树脂水分散液。通过环己烷/乙醇和丙酮两步萃取,对接枝共聚产物进行分离,用FTIR表征,并估算了接枝共聚物的组成。实验结果表明,所制备的粒径为纳米级的环氧树脂水分散液,具有良好的机械稳定性、冻融稳定性及贮存稳定性。ξ电位测定表明,产物在pH>8的条件下更为稳定。  相似文献   
17.
Background  Reduced left ventricular ejection fraction (LVEF) is a risk factor for poor outcomes in patients with coronary artery disease (CAD). Mental stress-induced myocardial ischemia (MSIMI) also identifies a subset of CAD patients at increased risk for future cardiovascular events. Susceptibility to MSIMI in patients with CAD and reduced LVEF is unknown. Methods and Results  We enrolled 182 patients (67 women) with a mean age of 64 years and a documented history of CAD in this study. Baseline resting ejection fraction was determined by use of technetium 99m sestamibi gated single photon emission computed tomography. Abnormal LVEF was defined as less than 45% for men and less than 50% for women (based on published norms for our software [Cedars-Sinai Medical Center]). All participants underwent mental stress testing with a public speaking task. Rest/stress myocardial perfusion single photon emission computed tomography was performed via conventional methodology. Images were visually compared for number and severity of perfusion defects by use of a scoring method from 0 to 4. A summed difference score was calculated as the difference between summed stress and rest scores. A score of greater than 3 was considered abnormal. MSIMI developed in 19% of patients with normal LVEF and 31% of those with reduced LVEF. There is no statistically significant difference between the two groups (P=.11). Conclusions  CAD patients with left ventricular dysfunction are equally susceptible to MSIMI as those with normal LVEF. This study was supported by grants HL 070265 and HL 072059 from the National Heart. Lung, and Blood Institute. This material is also the result of work supported by resources and with the use of facilities at the Department of Veterans. Affairs Medical Center, Gainesville, Fla.  相似文献   
18.
目的比较棉织布与无纺布制作的手术衣和手术洞巾等在手术铺巾时空气中的尘埃粒子数及术中抗渗液性能,为有效控制外科切口感染和预防医患交叉感染提供参考。方法将棉织布与无纺布制作的手术布类各备15包,包内内容均相同,经灭菌处理。应用尘埃粒子计数仪测定两组铺巾时、铺巾后及收巾时空气中的尘埃粒子数,同时在手术过程中观察其抗渗液性能。结果无纺布组在铺巾时、铺巾后及收巾时产生的尘埃粒子数显著少于棉织布组(P〈0.05,P〈0.01);其抗渗液率为100%,而棉织布组为0。结论无纺布抗渗液性能优,可减少手术环境中的尘埃粒子数,从而控制外科切口感染;其阻隔防护效能对患者和医护人员具有双重保护作用。  相似文献   
19.
大鼠直肠壁内淋巴管的微细分布和形态特征   总被引:4,自引:0,他引:4  
目的观察大鼠直肠壁内淋巴管的分布和形态、结构特点,为探讨直肠癌淋巴道转移的机制,提供形态学依据。方法用半薄、超薄切片、光镜和电镜下观察大鼠淋巴管的微细分布。结果大鼠直肠壁的黏膜固有层深部可见毛细淋巴管,黏膜下层、肌层和浆膜层均有毛细淋巴管和淋巴管。结论直肠壁各层内均有毛细淋巴管,除黏膜层外,还存有淋巴管。  相似文献   
20.
目的探讨对低射血分数患者施行非体外循环冠状动脉旁路移植术(off-pump coronary artery bypass grafting, OPCAB)预防性应用主动脉内球囊反搏(intraaortic balloon pump, IABP)辅助的必要性. 方法 2001 年1 月~2004年10月对64例低射血分数(LVEF≤40%)施行OPCAB,将64例分为2组:术前或术中预防性应用IABP辅助者列为IABP组,共19例;未应用IABP者列为对照组,共45例. 结果 IABP组与对照组在术后并发症手术死亡、脑血管意外、肾功能衰竭衰血滤、围手术期心肌梗死等方面无显著差异(χ2=0.000,P=1.000).IABP组术后需要延长呼吸机带机时间(超过24 h)的比例显著高于对照组(IABP组8例,对照组3例; χ2=9.429,P=0.002);IABP组术后监护时间延长(超过48 h)的比例显著高于对照组(IABP组14例,对照组19例; χ2=4.110,P=0.043). 结论在无IABP辅助的情况下,为低射血分数患者实施OPCAB手术是可行的.  相似文献   
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