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991.
In order to test the effect of peripheral blood mononuclear cell infusions on hematopoietic recovery in man we intensively leukapheresed a normal identical twin and obtained 9.8 x 10(10) peripheral blood mononuclear cells containing 4 x 10(5) CFU-C. These isologous cells were infused into his identical twin brother who had received 150 rad of total body irradiation and intensive combination chemotherapy as adjuvant therapy for Ewing's sarcoma. When compared to other patients receiving similar treatment, leukocyte recovery was accelerated by 3-4 wk, and occurred at a rate comparable to that induced by infusion of autologous cryopreserved marrow. Recovery of granulocytes, monocytes and platelets was not accelerated. The low number of CFU-C present in the preparation used ((one-eighth the number of CFU-C we usually obtain from bone marrow autograft collections) may have led to the pattern of hematopoietic recovery we observed in this patient.  相似文献   
992.
Jacob  RA; Sandstead  HH; Klevay  LM; Johnson  LK 《Blood》1980,56(5):786-791
Hematologic indices and iron balance data were obtained on 22 normal male volunteers who were subjected to a mean +/- SD phlebotomy of 164 +/- 34 ml whole blood/mo while living in a controlled environment. Over an average stay of 5 mo, volunteers did not develop anemia, but did display a reduction in iron stores that was quantitated by measurement of serum ferritin and iron balance. The percent saturation of transferrin and the usual erythrocyte parameters did not reflect changes in iron status. Loss of iron, which was calculated from quantitative phlebotomy and iron balance data, showed that a decrease of 1 ng of serum ferritin represented a loss of 4.5 +/- 5.3 mg of iron in 10 men whose initial serum ferritins were greater than 25 ng/ml, and 25.3 +/- 58.8 mg of iron in 7 men whose initial serum ferritins were less than 25 ng/ml. The period required for 3 volunteers who consumed a self-selected mixed diet at home to replace their depleted iron stores to prephlebotomy levels was about 4.5 mo. The sensitivity of serum ferritin as an index of iron stores was affirmed. In addition it was found that normal men who were consuming a mixed diet containing about 15 mg of iron daily and losing blood at a rate of 164 +/- 34 ml/mo did not increase their iron absorption sufficiently to compensate for the iron loss.  相似文献   
993.
We have developed a method for acquiring multiple tomographic subtraction images using a rapid, repetitive, circular tomographic motion. The method combines the principles of digital subtraction angiography (DSA) and electronic tomosynthesis. Fifteen patients were examined with the technique using single intravenous bolus injections of contrast material. The image sequence obtained during each injection was first processed with a nontomographic mask subtraction, and the result was then compared with the tomographic DSA scans synthesized from the same sequence. The effective section thickness was approximately 0.5 cm, with each section being 0.5-1.0 cm apart. Twelve of the intravenous DSA scans provided the necessary diagnostic or clinically useful information. Two of the three nondiagnostic scans were caused by avoidable technical reasons. In eight cases, the tomographic DSA scans were superior in quality to the nontomographic scans, exhibited significantly less artifact from patient motion and overlying bowel gas, and were effective in separating overlapping vessels. Tomosynthesis permits multiple electronic imaging of the area of interest without reinjection of contrast material and appears to be more informative than nontomographic intravenous DSA imaging.  相似文献   
994.
A noncomputerized, count-based technique for the determination of left ventricular ejection fraction (LVEF), which does not use geometric assumptions of left ventricular shape, was developed. The noncomputerized technique and computerized multigated ventriculography using both fixed and variable region-of-interest (ROI) methods were performed on 16 patients. The LVEFs obtained with the noncomputerized technique correlated well with both the fixed ROI computerized technique (r = .87) and the variable ROI computerized technique (r = .86). It is concluded that when a computer is not available, the noncomputerized technique is a valid alternative for the determination of LVEF in resting patients in stable sinus rhythm.  相似文献   
995.
996.
Radiation-induced injury of the esophagus   总被引:3,自引:0,他引:3  
Lepke  RA; Libshitz  HI 《Radiology》1983,148(2):375
  相似文献   
997.
拆冠器对双尖牙全冠及基牙冲击力实验研究   总被引:2,自引:0,他引:2  
目的:对拆冠器拆冠操作过程进行动态测试及分析,为正确安全使用拆冠器提供力学依据。方法:应用振动测试技术,通过CRAS振动、冲击、噪声采集处理系统采集处理拆冠操作时冲击力产生的瞬时弹性波,通过计算机分析计算得出测试结果。结果:全冠、基牙所受冲击力21.41±5.18公斤、作用时间1.58±0.10毫秒。冲击力越大,拆冠器对实验全冠、基牙作用时间就越长,反之则越短。结论:拆除双尖牙全冠时,冲击力的方向应该尽量与牙冠长轴平行,大小为24.59±5.98kg较为适合。  相似文献   
998.
999.
1000.
The development of national practice guidelines (NPGs) is an issue of much concern in healthcare policies world-wide to guarantee and to improve the quality and efficiency of care. The development and implementation of NPGs constitutes an important part of the quality of care policy of the Royal Dutch Physiotherapy Association (KNGF). This interest is due to pressure from society (policy-makers, healthcare managers, financiers and patients) on physiotherapists to ensure quality of care and to justify our position in the healthcare system. The development of NPGs can also be seen as a logical step in the process of professionalisation and quality assurance by physiotherapists.An NPG is described as a systematically developed statement, drafted by experts and directed at one aspect of the treatment of a health problem belonging to the domain of the profession. NPGs are based on the different stages of the physiotherapy care process, the available clinical evidence and expert consensus. Priority is given to a cost-effective approach and multidisciplinary consensus on diagnosis, treatment and primary or secondary prevention. Recommendations are based on the results of new or recorded systematic reviews or meta-analysis.NPGs are important state-of-the-art documents, which can guide professionals in their daily practice and make explicit to other relevant people what professionals can do in a certain situation or with a specific condition, and why they do it. NPGs have important functions, including supporting physiotherapists in their decision-making process; they are a frame of reference for orientation and educational purposes, they provide criteria for self-evaluation and peer review, and can initiate changes in established practice patterns.This paper describes the process and development of NPGs for physiotherapists in the Netherlands. In a companion paper the method and strategies for the implementation of NPGs and the need for evaluation of their outcome will be discussed.  相似文献   
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