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991.
实验室制得的碱式氯化铝,用~(27)Al NMR进行分析,发现在众多聚合体中存在[AlO_4Al_(12)(OH)_(24)(H_2O)_(12)]~(7+)离子,其化学位移相对于六水合铝离子[Al(H_2O)_6]~(3+)的零位移为δ=63ppm,试铁灵定时比色法对其存在进行了验证。研究了反应条件如酸浓度、铝酸当量比和陈化时间对产物组成及质量的影响,得出最佳条件为盐酸浓度16%,铝酸当量比为1:0.5,陈化时间为50h左右。  相似文献   
992.
Purpose To compare the differences in practice and outcome of all radiologically and surgically placed central venous catheters retrospectively over a 2-year period simultaneously, at a single institution. Methods A total of 253 Hickman catheters were inserted in 209 patients; 120 were placed radiologically in 102 patients and 133 were placed surgically in 107 patients. The indication was chemotherapy in 76% of radiological and in 47% of surgical cases; the remainder were for total parenteral nutrition and venous access. Results There were 6 (4.5%) primary surgical failures and a further 17 (13%) surgical cases requiring multiple placement attempts. Pneumothorax occurred once (0.8%) surgically and four times (3.3%) radiologically. There were no radiological primary misplacements but there were five (3.7%) surgical ones. Catheter or central vein thrombosis occurred in four (3.3%) radiological and five (3.7%) surgical cases. The rate of infection per 1000 catheter-days was 1.9 in radiologically placed catheters and 4.0 in surgically placed ones (p<0.001). Average catheter life-span was similar for the two placement methods (100±23 days). Conclusion Radiological placement is consistently more reliable than surgical placement. There are fewer placement complications and fewer catheter infections overall.  相似文献   
993.
根据《妇幼保健机构等级评审标准》(下称《标准》)要求,对全省20个妇幼保健机构现状进行了调查。结果显示:我省妇幼卫生工作基础薄弱,离《标准》要求差距较大;各机构间的发展极不平衡;县(市)级机构整体水平偏低,业务用房、人员、设备、床位等建设滞后;服务项目单一,二级专业分科不完善等矛盾较为突出。据此提出,在创等达标工作中,要依靠各级政府,努力争取各方面的支持,抓住机遇,迎接挑战,重点抓好软件建设,加强在职培训,积极引进人才,拓宽服务范围,规范自我,依法服务。  相似文献   
994.
995.
All-Union Hematology Research Center, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. I. Vorob'ev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 112, No. 11, pp. 500–501, November, 1991.  相似文献   
996.
Clinical Evaluation of a New Type of Centrifugal Pump   总被引:2,自引:0,他引:2  
Abstract: The major problems with existing centrifugal pumps are leakage, mechanical trauma, and thrombus formation. In consideration of these problems, a new compact centrifugal pump system was developed. The purpose of this study was to evaluate the new centrifugal pump system clinically. Ten patients underwent open heart surgery with a centrifugal pump or a roller pump. During surgery, hemodynamic and hematological data were obtained. A pulsatile assist device in the pump circuit was used in patients with severe heart disease. There was neither operative death nor hospital mortality, and there was no difference with regard to hemodynamic data between the two groups. The centrifugal pump group, however, had significantly lower hemolysis, especially during prolonged cardiopulmonary bypass. This centrifugal pump could also create sufficient pulsatile flow with a pulsatile assist device. Postoperative macroscopic and microscopic findings demonstrated the smooth surface of the pump without thrombus formation. This centrifugal pump system might be useful for prolonged cardiopulmonary bypass.  相似文献   
997.
The objectives of this study were to compare the ability of T1-weighted (T1W), proton density/T2-weighted (PD/T2W), and fat saturation (FS) PD/T2W magnetic resonance (MR) sequences for depiction of the knee collateral ligaments and related injuries, and to compare MR findings with clinical findings. Ten subjects with normal knee ligaments and 64 patients with suspected collateral ligament injuries underwent coronal T1W, PD/T2W, and FS PD/T2W imaging. Abnormalities ranged from edema surrounding the collateral ligaments (grade I) to complete disruption of ligamentous fibers (grade III). FS PD/T2W images improved definition of the medial collateral ligament (MCL) and lateral collateral ligament (LCL) compared with other sequences in 78% and 81% of patients, respectively. While the apparent grade of collateral ligament injury was similar with all pulse sequences in most patients, depiction of such injury was usually most conspicuous on FS PD/T2W images (MCL, 92% of patients; LCL, 38% of patients). In no patients were clinically diagnosed collateral ligament injuries undetected or understaged with MR imaging. MR findings indicated higher-grade MCL and LCL injuries than did clinical examination in 24 and 15 patients, respectively.  相似文献   
998.
999.
There is abundant data on cancellous bone in the aging human spine, but little relating to the growing vertebral cancellous bone in childhood and adolescence. The purpose of this study was to map vertebral cancellous bone in a growth and age series of historic skeletal samples and to make comparisons with data published on recent material. Lumbar vertebral bodies were collected from 65 skeletons (0–60 years) from a medieval Nubian population. Ethnohistoric information was collected to interpret conditions that might have influenced bone structure and metabolism. The cancellous bone was studied three dimensionally, using stereophotography and scanning electron microscopy and morphometrically by performing a semiautomatic structural analysis on digitized backscattered electron images of polymethacrylate-embedded material. The cancellous bone structure in the children consisted mainly of a densely packed, uniform network of small rodlike trabeculae. The greatest bone volume fraction with small, more platelike trabeculae was observed during adolescence. In young adults, larger platelike trabeculae were present in the central zone and smaller trabeculae in the superior and inferior zones, as described for modern skeletal material. Structural changes associated with aging were observed much sooner than in modern man. By the estimated age of approximately 50–60 years, the predominant architectural elements were slender rarified rods in both sexes. The ethnohistorical data suggest that this was essentially a black African population of physically active peasants, not likely to suffer Vitamin D insufficiency or deficient calcium intake. Thus an earlier onset of the biological age changes in cancellous bone found in modern populations was probably prevalent. Received: 1 March 1996 / Accepted: 31 December 1996  相似文献   
1000.
全锁髓内钉的设计及其临床应用   总被引:30,自引:0,他引:30  
锁式髓内钉是近十余年来国际上有关髓内钉骨折内固定技术的三大进展之一。我院骨科在参考Huckstep钉的基础上,设计了改进型Huckstep钉(即全锁髓内钉,简称全锁钉,下同)及其手术器械和手术方法,不需要X线辅助设备,用于治疗复杂股骨骨折。自1987年4月~1992年12月用全锁钉治疗复杂股骨骨折48例,其中男33例、女15例;年龄最大55岁,最小20岁,平均34.6岁。致伤原因:车祸21例、高处坠落伤14例、工业伤10例、其他3例。骨折部位:股骨干上1/3骨折17例、中1/3骨折4例、下1/3骨折5例、全股骨多处骨折5例(其中股骨骨折合并股骨颈骨折3例、合并转子间骨折和转子下骨折各1例)、股骨转子间骨折12例,股骨转子下骨折5例。48例中39例获得随访,最长107个月,最短42个月,平均66.4个月。优30例(76.9%),良7例(18.0%),失败2例(5.1%)。  相似文献   
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