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991.
Yasuko Tomizawa Asako Tokumine Shinji Ninomiya Naoki Momose Toru Matayoshi 《Journal of artificial organs》2008,11(3):117-122
The heart-lung machines for open-heart surgery have improved over the past 50 years; they rarely break down and are almost always equipped with backup batteries. The hand-cranking procedure only becomes necessary when a pump breaks down during perfusion or after the batteries have run out. In this study, the performance of hand cranking a roller pump was quantitatively assessed by an objective method using the ECCSIM-Lite educational simulator system. A roller pump connected to an extracorporeal circuit with an oxygenator and with gravity venous drainage was used. A flow sensor unit consisting of electromagnetic sensors was used to measure arterial and venous flow rates, and a built-in pressure sensor was used to measure the water level in the reservoir. A preliminary study of continuous cranking by a team of six people was conducted as a surprise drill. This system was then used at a perfusion seminar. At the seminar, 1-min hand-cranking drills were conducted by volunteers according to a prepared scenario. The data were calculated on site and trend graphs of individual performances were given to the participants as a handout. Preliminary studies showed that each person's performance was different. Results from 1-min drills showed that good performance was not related to the number of clinical cases experienced, years of practice, or experience in hand cranking. Hand cranking to maintain the target flow rate could be achieved without practice; however, manipulating the venous return clamp requires practice. While the necessity of performing hand cranking during perfusion due to pump failure is rare, we believe that it is beneficial for perfusionists and patients to include hand-cranking practice in periodic extracorporeal circulation crisis management drills because a drill allows perfusionists to mentally rehearse the procedures should such a crisis occur. 相似文献
992.
低频超声透皮给药的研究进展与应用 总被引:1,自引:0,他引:1
低频超声可以增强包括大分子药物在内的许多药物的透皮传输,其主要机制是超声的空化作用,大多数人认为是通过改变角质层角化细胞排列结构来提高皮肤渗透能力的.低频超声透皮给药已被人们用于离体实验和动物活体实验,到目前为止,无论是小分子透皮传输还是大分子透皮传输都有很多成功的例子.但是真正通过低频超声透皮导入药物进行治疗的临床应用报道很少,需要更进一步大量的临床试验以确定其安全性与实用价值.一旦其安全性得以证实,合适的低频超声透皮仪研制成功,低频超声快速透皮必将成为一种安全、有效、可控、经济的新型给药方式. 相似文献
993.
994.
995.
Chromosome 13q neocentromeres: molecular cytogenetic characterization of three additional cases and clinical spectrum 总被引:3,自引:0,他引:3
Li S Malafiej P Levy B Mahmood R Field M Hughes T Lockhart LH Wu Z Huang M Hirschhorn K Velagaleti GV Daniel A Warburton PE 《American journal of medical genetics》2002,110(3):258-267
We report three new cases of chromosome 13 derived marker chromosomes, found in unrelated patients with dysmorphisms and/or developmental delay. Molecular cytogenetic analysis was performed using fluorescence in situ hybridization (FISH) with chromosome-specific painting probes, alpha satellite probes, and physically mapped probes from chromosome 13q, as well as comparative genomic hybridization (CGH). This analysis demonstrated that these markers consisted of inversion duplications of distal portions of chromosome 13q that have separated from the endogenous chromosome 13 centromere and contain no detectable alpha satellite DNA. The presence of a functional neocentromere on these marker chromosomes was confirmed by immunofluorescence with antibodies to centromere protein-C (CENP-C). The cytogenetic location of a neocentromere in band 13q32 was confirmed by simultaneous FISH with physically mapped YACs from 13q32 and immunofluorescence with anti-CENP-C. The addition of these three new cases brings the total number of described inv dup 13q neocentic chromosomes to 11, representing 21% (11/52) of the current overall total of 52 described cases of human neocentric chromosomes. This higher than expected frequency suggests that chromosome 13q may have an increased propensity for neocentromere formation. The clinical spectrum of all 11 cases is presented, representing a unique collection of polysomy for different portions of chromosome 13q without aneuploidies for additional chromosomal regions. The complexity and variability of the phenotypes seen in these patients does not support a simple reductionist view of phenotype/genotype correlation with polysomy for certain chromosomal regions. 相似文献
996.
George N Papanikolaou Maria S Baltogianni Despina G Contopoulos-Ioannidis Anna-Bettina Haidich Ioannis A Giannakakis John PA Ioannidis 《BMC medical research methodology》2001,1(1):3
Background
Guidelines published in major medical journals are very influential in determining clinical practice. It would be essential to evaluate whether conflicts of interests are disclosed in these publications. We evaluated the reporting of conflicts of interest and the factors that may affect such disclosure in a sample of 191 guidelines on therapeutic and/or preventive measures published in 6 major clinical journals (Annals of Internal Medicine, BMJ, JAMA, Lancet, New England Journal of Medicine, Pediatrics) in 1979, 1984, 1989, 1994 and 1999.Results
Only 7 guidelines (3.7%) mentioned conflicts of interest and all were published in 1999 (17.5% (7/40) of guidelines published in 1999 alone). Reporting of conflicts of interest differed significantly by journal (p=0.026), availability of disclosure policy by the journal (p=0.043), source of funding (p < 0.001) and number of authors (p=0.004). In the entire database of 191 guidelines, a mere 18 authors disclosed a total of 24 potential conflicts of interest and most pertained to minor issues.Conclusions
Despite some recent improvement, reporting of conflicts of interest in clinical guidelines published in influential journals is largely neglected.997.
右旋糖酐40、70对红细胞与内皮细胞粘附的影响 总被引:1,自引:0,他引:1
采用流室显微观察系统,定量研究右旋糖酐40(DX40)和右旋糖酐70(DX70)对红细胞与内皮细胞动态粘附特性的影响。统计分析处理数据,得到反映切应力与细胞间动态粘附数关系的经验公式及粘附特征常数a,b值。a值反映红细胞的初始粘附数,b值反映随切应力增大,粘附数减小的速率。DX70实验组的a值大于DX40组的,而b值的情况相反。故结果显示切应力越大,粘附的红细胞越少;DX40使红细胞的粘附明显减少;DX70使红细胞粘附显著增加。由此提示不同长度的细胞桥接分子对红细胞的粘附影响不同,且临床上选用DX40作血浆扩容剂较DX70优越得多 相似文献
998.
重组人纽兰格林对正常恒河猴心脏的影响 总被引:1,自引:0,他引:1
探索重组人纽兰格林对健康成年恒河猴心脏的作用.将10只健康成年实验恒河猴随机分为实验组及对照组,分别注射等量重组人纽兰格林及生理盐水,采用超声心动图对用药前、用药即刻60 s内及用药10 d后相关指标进行测量,比较两组之间及不同时间之间各指标的差异.结果表明:重组人纽兰格林对健康实验恒河猴的舒张末期左室内径及容积、收缩末期左室容积、每搏量有影响,且随着用药时间的延长4者均增大,而重组人纽兰格林对健康恒河猴的左室射血分数及短轴缩短率没有显著影响.本研究认为重组人纽兰格林对健康成年恒河猴左心室容积有影响,而对心肌收缩力无显著影响. 相似文献
999.
Helen Elden Hans-Christian Ostgaard Monika Fagevik-Olsen Lars Ladfors Henrik Hagberg 《BMC complementary and alternative medicine》2008,8(1):34
Background
Previous publications indicate that acupuncture is efficient for the treatment of pelvic girdle pain, PGP, in pregnant women. However, the use of acupuncture for PGP is rare due to insufficient documentation of adverse effects of this treatment in this specific condition. The aim of the present work was to assess adverse effects of acupuncture on the pregnancy, mother, delivery and the fetus/neonate in comparison with women that received stabilising exercises as adjunct to standard treatment or standard treatment alone. 相似文献1000.
Biochemical profile of blood serum of siraz <Emphasis Type="Italic">Capoeta capoeta umbla</Emphasis>
Abdulkadir Bayir A. Necdet Sirkecioğlu Harun Polat N. Mevlüt Aras 《Comparative clinical pathology》2007,16(2):119-126
Seasonal changes in blood plasma biochemistry of siraz Capoeta capoeta umbla were determined throughout 1 year. In the present study, while the highest values for glucose and globulin were found in
winter, the values for increased activities of total protein, albumin, calcium, sodium levels, albumin/globulin ratio, lactate
dehydrogenase, and alkaline phosphatase were determined in summer. We determined that blood biochemistry values of siraz,
which were positively affected by water temperature and pH, except glucose and globulin. Glucose and globulin were negatively
affected by water temperature and pH. Consequently, it was concluded that the seasons are key factors when blood parameters
are used as biomarkers for environmental alterations. It is difficult to define the most important factors affecting seasonal
changes of blood biochemistry in fish. 相似文献