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81.
82.
在定量的构效关系研究中,多重回归分析选人的参数,多是用穷举所有方程实现的。本文提出一种改进的逐步回归算法,计算实例表明,是个行之有效的方法。 相似文献
83.
We have investigated the ability of liposome-bound encephalitogenic peptide to suppress experimental allergic encephalomyelitis (EAE) in the guinea pig. EAE was induced by challenge with the encephalitogenic peptide, residues 113-122 of human myelin basic protein (MBP) in complete Freund's adjuvant. The peptide was acylated with stearic acid in order to anchor it to the lipid bilayer. The liposomal-bound peptide effectively suppressed clinical signs of EAE at relatively low doses, when given subcutaneously or intraperitoneally without incomplete Freund's adjuvant, several days after challenge. In vitro proliferation of lymphocytes from treated, protected animals in response to the peptide was greatly decreased but that to the purified protein derivative of tuberculin antigen was not, indicating an antigen-specific effect. However, histological signs of EAE were not reduced. The free peptide in solution was somewhat less effective when given intraperitoneally but was as or nearly as effective as liposome-bound peptide when given subcutaneously. Binding to liposomes may decrease the rate of clearance or degradation of the peptide when given intraperitoneally. 相似文献
84.
85.
U. Lehmann G. Regel B. Ellendorf E. Rickels M. Lorenz H. Becker H. Tscherne 《Der Unfallchirurg》1997,100(9):705-710
Summary
A total of 208 multiple trauma patients with head injury (HI) were investigated who had been treated in the period from 1990
to 1995. The average age was 35.2 ± 17.7 years; the injury severity according to ISS was 30.2 ± 8.6 points; 20.5 % died as
a result of the HI; the mortality of all patients was 26.5 %. The Glasgow Coma Scale (GCS) was determined at an average of
22 min after trauma (8.0 ± 4.3 points) at the scene of accident. The patients were classified according to GCS into minor
HI (group 1: 14–15 points), moderate HI (group 2: 9–13 points) and severe HI (group 3: 3–8 points). Patient outcome was assessed
by the Glasgow Outcome Scale (GOS) and was classified as good (GOS 4 and 5) and poor (GOS 1, 2 and 3) outcome. At the latest,
2 h after trauma, a CT scan of the head (CCT) was done. The HI groups are compared regarding frequency of types of injury.
In all HI groups the fractures of the bony face occurred at the same frequency (36.0–38.9 %). The frequency of calotte fractures
(Kal-Fx) increased from group 1 (8.0 %) to 2 (19.2 %) and 3 (25.6 %); fractures of the skull base significantly differed between
group 1 (16.0 %), 2 (7.8 %) and 3 (33.4 %). Epidural hemorrhage (EDB) appeared only in group 2 (7.8 %) and 3 (6.7); subdural
hemorrhage was found in group 1 (2.7 %), 2 (7.8 %) and 3 (10.0 %). Subarachnoid hemorrhage (SAB) was significantly more frequently
seen, dependent on HI severity, in group 3 (26.7 %) compared to group 2 (11.7 %) and 1 (8.0 %). Intracerebral contusion (ICK)
significantly increased from group 1 (12.0 %) to 2 (27.3) and 3 (45.6 %). Brain swelling (BS) also significantly increased
from group 1 (8.0 %) to 2 (19.5 %) and 3 (49.0 %) and lesions of ventricles (VL) from group 1 (2.7 %) to 2 (11.7 %) and 3
(20.0 %). Midline shift (13.4 %) and signs of herniation (4.5 %) only occurred in group 3. The analysis of correlation/regression
and receiver operating characteristics was able to predict 79 % of patients' outcome accurately using GCS (r 0.54; P < 0.0001) alone, using CCT (r 0.65; P < 0.0001) 87 % were correctly predicted with significant variables Cal-Fx, EDB, SAB and BS. CCT with GCS (r 0.74; P < 0.0001) were able to predict 88 % accurately with significant variables Cal-Fx, EDB, BS and GCS. The combination of CCT
with GCS, age and ISS (r 0.78; P < 0.0001) was able to predict only 87 % correctly, although the r value was the highest; significant variables were Kal-Fx, EDB, BS, VL, GCS, age and ISS.
相似文献
86.
环孢菌素治疗用激素类药无效的多发性硬化 总被引:9,自引:0,他引:9
目的探讨环孢菌素(CsA)治疗用激素类无效的多发性硬化(MS)的效果。方法对激素等治疗5个月以上病情无明显好转或仍在加重的10例MS,用CsA5mg·kg-1·d-1,疗程至少2个月,然后根据病情逐渐减量,最后小剂量维持用药。统计各个治疗期及最后随访(6~32个月后)的扩充致残量表(EDSS)评分和脑MRI病灶数。结果激素治疗前后EDSS差异无显著性意义(P>0.20);CsA足量治疗使EDSS评分下降及脑MRI病灶数减少(P<0.05);最后随访EDSS评分进一步下降(P<0.01),其中4例复查了MRI,3例病灶数进一步减少。CsA治疗未见严重毒副作用。结论CsA可治疗用激素类无效的MS。 相似文献
87.
Amyloidosis led to thickening of the urinary bladder wall, with hypointensity in T2-weighted images, which was distinguished
from multiple myeloma involvement.
Received: 3 April 1995/Accepted: 7 August 1995 相似文献
88.
Tsuyoshi Takahashi Keiji Iwasaki† Paul S. Malchesky† Hiroaki Harasaki† Michiaki Matsushita† Yukihiko Nosé† Henry Rolin III‡ Phillip M. Hall‡ 《Artificial organs》1993,17(3):153-163
Abstract: Pyridoxalated-hemoglobin-polyoxyethylene conjugate (PHP), which is made from out-dated human red blood cells by two major chemical modifications, namely pyridoxalation and conjugation with polyoxyethylene (POE), is currently under development as a physiological oxygen carrier. This study assessed the effects of PHP-88 solution, which contains 8% (wt/vol) each of hemoglobin (Hb) and maltose, on renal function when it was infused 3 times every other day into the intact circulation of 8 dogs (5 dogs for the PHP group and 3 for the control group; 20 ml/kg for the first infusion, and 10 ml/kg each for the second and third infusions, at the rate of 2.5 ml/h/kg). Serial determinations of glomerular filtration rate (GFR) and renal plasma flow (RPF) were carried out pre- and postinfusion for up to 3 months along with measurements of blood and urine analyses, urine output rate, fractional excretion of sodium (FES), and free water clearance (CH2O). The results showed that plasma colloid osmotic pressure (COP) elevated an average of 3.3 mm Hg (p = 0.0085), and GFR and RPF tended to increase by 13% (NS) and 38% (NS), respectively, immediately after the third infusion with PHP solution. Urine output rate increased during and after the infusion, and FES and CH2O also increased for 24 h after the infusion in both groups. Blood urea nitrogen, serum creatinine, and serum Na+ concentrations were not affected greatly by the infusions, but hematocrit was decreased by 8% in the PHP group, indicating approximately a 42% expansion of plasma volume. These changes were observed to return to their preinfusion levels by 1 week postinfusion. Renal histology of the PHP group obtained at 2 weeks postinfusion revealed vacuole formation in the proximal tubules which was not associated with any pathologic changes indicative of cell death or regeneration. In 4 out of 5 dogs at 3 months postinfusion (necropsy), the vacuoles were not present. Though urinary N-acetyl β-glucosaminidase (NAG) activity had significantly increased after infusion, it returned to the preinfusion level by 1 month postinfusion. No detrimental effect of vacuoles on the assessed renal tubular functions was confirmed in the present study. The result demonstrated that multiple infusions of PHP solutions were well tolerated in normal dogs, and the observed effects were conceived predominantly attributable to the physiological response of the kidneys to an oncotic load into the circulation, which produced plasma volume expansion. 相似文献
89.
高容量血液滤过治疗多器官功能障碍综合征的分析 总被引:4,自引:0,他引:4
目的研究高容量血液滤过 (HVHF)在多器官功能障碍综合征 (MODS)治疗中的作用。方法 19例MODS患者 ,随机选择 10例行HVHF ,另 9例行常规连续性静脉 静脉血液滤过 (CVVH)。于治疗前和治疗开始后 2、4、8h动脉采血 ,检测血气、血肌酐 (Scr)、尿素氮 (BUN)、肿瘤坏死因子(TNFα)、白细胞介素 1(IL 1β)、白细胞介素 6 (IL 6 )的变化。 结果HVHF组与CVVH组于治疗开始后4h血Scr、BUN均显著下降 ,肾功能改善。HVHF组血TNFα、IL 1β、IL 6治疗前分别为 ( 1795± 5 0 6 )ng/L、( 96 4± 185 )ng/L、( 1332± 4 15 )ng/L ,治疗开始后 4h为 ( 12 6 5± 397)ng/L、( 5 11± 12 4 )ng/L、( 72 6±2 4 3)ng/L ,差异有显著意义 ,P <0 0 5。CVVH组血TNFα治疗前为 ( 1799± 5 11)ng/L ,治疗开始后 4h为 ( 132 7± 4 2 1)ng/L ,差异有显著意义 ,P <0 0 5。HVHF组死亡 3例 ( 3/ 10 ) ,CVVH组死亡 5例 ( 5 / 9) ,差异有显著意义 ,P <0 0 5。结论HVHF可通过对流和AN6 9膜的吸附作用清除大量炎症介质 ,改善MODS患者的预后 相似文献
90.
气象因素与霍乱发病关系的生态学研究 总被引:1,自引:0,他引:1
谈荣梅 《中国预防医学杂志》2004,5(5):343-345
目的探讨气象因素与霍乱发病的关系.方法将绍兴地区1991~2001年霍乱各年6~11月份月平均发病率数据进行正态化处理后,再利用方差分析、回归分析对可能影响霍乱发病的气温、气压、相对湿度、日照时数、降水量等5项研究变量进行单因素相关分析和多元逐步回归分析.结果霍乱的发病与气温呈显著性正相关,与气压呈显著性负相关.结论霍乱发病与高气温、低气压有关. 相似文献