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101.
枸橼酸抗凝血液透析   总被引:5,自引:0,他引:5  
研究解剖高危出血患者血液透析的抗凝方法-局部枸橼酸抗凝的临床应用和疗效。方法:采用1.6mol/L的枸橼酸钠、空心纤维透析器和普通含钙碳酸氢盐透析,观察RCA透析对患者出血、体外循环凝血、血游离钙、总钙、K^+,Na^+,pH,HCO^-3,Scr,BUN及血清枸橼酸浓度的影响。  相似文献   
102.
Hypertension after cardiac surgery is common and requires accurate control by carefully regulated infusions of drugs such as sodium nitroprusside. A microprocessor-based controller has been designed to close the loop between the blood pressure response and the infusion rate of a hypotensive drug. This system has been refined by computer simulation of the blood pressure response to sodium nitroprusside and by experience gained in using the controller in eleven patients in the early recovery period after cardiac surgery. The controller was able automatically to maintain blood pressure within 10% of a specified value. Provision of sophisticated safety features in automatic drug infusion controllers is essential for patient protection.  相似文献   
103.
Gynecological operations with artificial cardiac pacing: report of 2 cases   总被引:3,自引:0,他引:3  
Z B Xu 《中华妇产科杂志》1987,22(1):22-3, 62
  相似文献   
104.
本文总结了14例应用刮治和自体骨移植术治疗大型牙源性角化囊肿的方法,14例植骨均成活,4例术后囊肿复发,再次手术,指出:与骨断切除治疗大型角化囊肿的方法比较,此法最大的优点是有利于保持患者面容和咀嚼功能,并对大型角化囊肿的手术原则,自体骨移植问题及手术注意事项进行了讨论。  相似文献   
105.
210例Ⅱ孔型房间隔缺损术后发生心律失常90例,14种类型,共292例次,其中,室上性占96%。30例需药物治疗,93%的患者出院时恢复正常。本文着重分析心律失常的特点,讨论影响因素及预防措施。  相似文献   
106.
107.
Fu SL  Ma ZW  Yin L  Iannotti C  Lu PH  Xu XM 《Neuroscience》2005,135(3):851-862
To determine whether neural precursor cells have region-specific growth properties, we compared the proliferation, mitogenicity, and differentiation of these cells isolated from the embryonic day 16 rat forebrain and spinal cord. Neural precursor cells isolated from both regions were cultured in growth medium supplemented with epidermal growth factor, basic fibroblast growth factor, or epidermal growth factor+basic fibroblast growth factor. Under all three conditions, both neural precursor cell populations proliferated for multiple passages. While spinal cord-derived neural precursor cells proliferated moderately faster in epidermal growth factor-enriched growth medium, brain-derived cells proliferated much faster in basic fibroblast growth factor-enriched growth medium. When exposed to both epidermal growth factor and basic fibroblast growth factor, the two neural precursor cell populations expanded and proliferated more rapidly than when exposed to a single factor, with brain-derived neural precursor cells expanding significantly faster than spinal cord-derived ones (P<0.0001). Differentiation studies showed that both neural precursor cell populations were multi-potent giving rise to neurons, astrocytes, and oligodendrocytes. However, neuronal differentiation from brain-derived neural precursor cells was greater than spinal cord-derived ones (11.95+/-5.00% vs 1.92+/-1.13%; passage 2). Further, the two neural precursor cell populations differentiated into a similar percentage of oligodendrocytes (brain: 8.66+/-5.85%; spinal cord: 7.69+/-3.91%; passage 2). Immunofluorescence and Western blot studies showed that neural precursor cells derived from both regions expressed receptors for basic fibroblast growth factor and epidermal growth factor. However, brain-derived neural precursor cells expressed higher levels of the two receptors than spinal cord-derived ones in growth medium containing epidermal growth factor+basic fibroblast growth factor. Thus, our results showed that neural precursor cells isolated from the two regions of the CNS have distinct properties and growth requirements. Identifying phenotypic differences between these neural precursor cell populations and their growth requirements should provide new insights into the development of cell therapies for region-specific neurological degenerative diseases.  相似文献   
108.
109.
根据呼气相胸片中肺部区域灰度较高的特点,通过边缘提取和边缘跟踪确定胸部区域,运用最大类间方差方法确定图像分割的阈值.再提取出肺部区域,然后求出肺部的灰度均值。但这样的结果并不理想。于是在此基础上提出修正方案,即以肺部灰度均值和骨骼灰度均值的比值作为特征值.即比例法。此方法可以较客观的识别呼气相胸片。最后用类间距离对这两种方法进行了量化比较。  相似文献   
110.
Piglets infected in utero with porcine reproductive and respiratory syndrome virus (PRRSV) are born severely immunocompromised. In this article we more closely examine the effects of in utero PRRSV infection on circulating and thymic T cell populations. Numbers of CD4+, CD8+, and dual-positive lymphocytes were quantitated in circulation and in the thymus during the 2 weeks following birth. At birth we found that the number of circulating lymphocytes was suppressed by 60%. Lymphocyte numbers were also suppressed by 42% at day 7, but by day 14 the number of lymphocytes had rebounded and was actually 47% greater than controls. At birth and day 7, a drop in the number of CD4+ cells could partially explain the suppression we observed, while the rebound in total lymphocyte numbers seen at day 14 was due to a nearly fourfold increase in the number of circulating CD8+ cells. As a result, the normal CD4+:CD8+ ratio of between 1.4 and 2.2 for neonatal pigs was reduced to 0.1-0.5. The thymuses of infected piglets were found to be 50% smaller than those of control pigs and were characterized by cortical involution and severe cortical depletion of thymocytes. Analysis of the population of thymocytes revealed that double-positive thymocytes were suppressed to a greater degree than either single positive subpopulation. In addition, we show that the number of thymocytes undergoing apoptosis was increased twofold in piglets infected with PRRSV. Taken together, these results help explain the dramatic immunosuppression observed in neonatal animals infected in utero with PRRSV.  相似文献   
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