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921.
根据胜利黄岛原油的性质,在筛选了几十种破乳剂的基础上,选择了酚醛树脂和环氧环烷,环氧乙烷的嵌段共聚物作破乳剂,探讨了破乳剂组成对原油脱水,脱盐以及界面张力的影响,通过静态脱盐,脱水试验,得到了适合黄岛原油的最佳破乳剂组成。 相似文献
922.
用乙二醇法诱导大鼠产生草酸钙结石,用45~Ca示踪测定法了解中草药复方制剂(PESM)对草酸钙结石形成的抑制作用。结果显示,实验组肾脏放射性强度明显减少(实验组3.47±3.52cpm/mg,对照组10.89±14.24cpm/mg)。干肾重量明显下降(实验组306.0±47.0mg,对照组343.1±59.4mg),说明PESM能明显抑制肾脏草酸钙结石的形成。 相似文献
923.
Key role for pregnenolone in combination therapy that promotes recovery after spinal cord injury. 总被引:8,自引:1,他引:7
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L Guth Z Zhang E Roberts 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(25):12308-12312
Controlled compressive injury to rat spinal cord was chosen to test therapies that might attenuate the progression of tissue destruction and locomotor deficits that characteristically occur after spinal injury. A highly significant reduction of damage was achieved by immediate postinjury treatment with a combination of the following: an antiinflammatory substance, indomethacin; a stimulator of cytokine secretion, bacterial lipopolysaccharide; and the parent steroid, from which all other steroids arise, pregnenolone. This treatment reduced histopathological changes, spared tissue from secondary injury, and increased restoration of motor function. Remarkably, 11 of 16 of the animals treated with the above combination were able to stand and walk at 21 days after injury, 4 of them almost normally. The results were far superior to those obtained in controls or in animals to which the substances were given separately or in combination of two. This approach may prove to be applicable to nervous system injury, in general, and to injury in other tissues. 相似文献
924.
测定27例肾腺癌的DNA含量,并联系肿瘤的分级等部分形态学指标,对透明细胞型和颗粒细胞型肿瘤进行比较分析。发现:透明细胞型肾腺癌的分化一般较好,DNA以二倍体为主,预后相对较好;而颗粒细胞型肾腺癌的分化较差,DNA以非二倍体为主,其预后较差。 相似文献
925.
乙二胺四乙酸铁钠强化酱油可接受性的调查研究 总被引:2,自引:0,他引:2
为了解乙二胺四乙酸铁钠 (NaFeEDTA)强化酱油的接受程度 ,了解人们对铁营养知识和铁缺乏危害的认识情况 ,在贵州省对参加铁强化酱油干预试验的部分受试人群以家庭为单位进行问卷调查。共收回有效调查表 187份 ,基本上覆盖了试验点的各年龄组人群 ,具有较高的代表性。调查结果显示 :被调查者中 6 9 5 %认为铁强化酱油比未强化酱油有营养 ,2 8 9%认为铁强化酱油一般 ,只有 1 6 %中认为铁强化酱油差。 97 9%认为铁强化酱油可预防缺铁性贫血。 5 8 8%表示会选用铁强化酱油 ,另有 4 0 1%的人对是否选用拿不定主意。调查表明NaFeEDTA强化酱油有很高的可接受性 ,可接受度达 84 1% ,应用前景较好。 相似文献
926.
Alterations in the superoxide dismutase gene of an isoniazid-resistant strain of Mycobacterium tuberculosis.
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Y Zhang M J Garcia R Lathigra B Allen C Moreno J D van Embden D Young 《Infection and immunity》1992,60(6):2160-2165
Genetic analysis of a set of six Mycobacterium tuberculosis strains differing in virulence for the guinea pig revealed an altered restriction enzyme fragmentation pattern associated with the superoxide dismutase (SOD) gene in a low-virulence, isoniazid-resistant strain. In addition, it was found that the SOD enzyme produced by the isoniazid-resistant strain differed in its electrophoretic mobility from the SOD of other M. tuberculosis strains. Detailed analysis of these strain-specific differences showed that the restriction fragment length polymorphism resulted from the presence of a copy of a repetitive element 552 bp upstream of the SOD gene and that the anomalous electrophoretic mobility arose from a single nucleotide change, resulting in replacement of an aspartic acid residue by histidine in the SOD enzyme of the isoniazid-resistant strain. Possible relationships between genetic changes and strain-dependent differences in virulence are discussed. 相似文献
927.
To study myelinated nerve fiber regeneration during aging, the right sciatic nerves of 6- and 24-month-old mice were crushed at the sciatic notch. Two, 4, and 8 weeks later, both groups of mice were perfused. The sciatic nerves were processed so that the transverse sections of each nerve subsequently studied by light and electron microscopy included the entire posterior tibial fascicle 5 mm distal to the crush site. Two weeks after axotomy, fascicles of aging mice contained significantly fewer regenerated myelinated fibers than those of young adults. After 4 weeks, the difference in the number of myelinated fibers was less. However, measurements of myelinated fibers in fascicles of aging mice showed that areas of Schwann cell cytoplasm and myelin were significantly reduced at all intervals. In contrast, although axon diameters in aging mice were somewhat less 2 weeks after crushing, the difference decreased with time, suggesting that in nerves of aging mice, regenerative responses of Schwann cells were more affected than those of axons. Other experiments in young mice showed that myelinated fiber regeneration could be retarded by suppressing macrophage responses and was not significantly changed by conditioning lesions before crush injury. 相似文献
928.
A study on various symptoms of chronic hepatitis treated with radix astragali and its regulative effect to levels of serum hormone
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Ke-zhou Liu Zhong-hang Tong Ming-tai Zhang Wei-zheng Gu Zhi-rong Huang Bi-he Shen Pei-ren Cai Gui-lang Zhu Wen-nan He Lan-sheng Feng Lie-ming Ding Zhi Chen Jian-hua Jin Xiu-zhi Zhang Qian-yan Yu Shui-jin Tong Ping Ye 《中国结合医学杂志》1995,1(2):118-121
Sixty-seven cases of chronic hepatitis were treated with Radix Astragali. After treatment (2-month course), the clinical improvement rate in 38 cases of the Stagnation of the Liver-Qi and Deficiency of the Spleen type was 92.1%, and in 26 cases of the Deficiency of Liver Yin and Kidney Yin type was 88.5%, more effective than in the control group (P<0.05). The regulative effect to the levels of serum hormone was observed in the patients of the Stagnation of the Liver-Qi and Deficiency of the Spleen type treated with this medicine. The results showed that the levels of serum triiodothyronine, estradiol (female) and testosterone (male) were increased after treatment (1.40±1.38 ng/dl, 129.30±1.23 pg/ml and 496.24±1.47 ng/dl). Pre-treatment levels were 1.22±1.49 ng/dl, 104.60±1.45 pg/ml and 398. 17±1.55 ng/dl respectively (P<0.05); however, the level of serum prolactin (2.75±4.46 ng/ml) was lower after treatment than before treatment (3.20±3.82 ng/ml,P<0.05). No obvious changes were observed in the levels of serum follicle stimulating hormone, luteinizing hormone, thyroid stimulating hormone, thyroxine, triiodothyronine uptake ratio and cortisol after treatment. 相似文献
929.
距骨的血液供应及其临床意义 总被引:30,自引:0,他引:30
本文观察了24侧尸体足标本,均无已知临床血管疾病。在死后36~48小时之间行动脉灌注ABS填充剂,以化学腐蚀和手工剔除的方法清除软组织。距骨的血供来自小腿下部三根主要动脉的分支,即跗骨管动脉和三角支、近端和远端跗骨窦动脉、颈上支及后结节血管丛。跗骨管动脉常发自足底内侧动脉,而三角支多单独自胫后动脉发出;跗骨管动脉通常比三角支和跗骨窦动脉都来得细小。以上的这些动脉相互吻合,形成了一个骨膜血管网,覆盖于全部的距骨非关节面上。而且,环绕着跗骨管、跗骨窦、距骨颈的上面和距骨体部的内侧面,由三角支、跗骨管动脉、跗骨窦动脉、颈上支及其相互之间的吻合血管网形成了一个不定形的距骨动脉环。本文还讨论了距骨缺血性坏死与动脉环的可能关系,距骨骨折脱位或手术后的缺血性坏死是由于距骨动脉环的毁损或功能受影响所致。三角支在距骨骨折脱位时具有重要意义,手术或手法复位时应注意保护。 相似文献
930.
Grose-Kempf 带锁髓内钉在股骨干骨折中的应用 总被引:1,自引:0,他引:1
作者从1988~1995年末用Grose-kempf钉(简称GK钉)治疗股骨干骨折49例(50个股骨),其中新鲜骨折29例(30个股骨),陈旧性骨折16例,病理骨折4例。外伤性骨折45例中,随访半年以上43例,骨折全部愈合,下肢功能及关节活动良好。4例病理骨折,其中3例术后分别存活16个月、18个月、24个月,另1例为成骨不全,术后患肢功能较健侧无差别。GK钉扩大了髓内钉手术适应证,可用于股骨干的粉碎性骨折、多发性骨折、陈旧性骨折不愈合及病理性骨折。对于合并脑干损伤、血管损伤、骨筋膜室综合征的股骨干骨折,用GK钉固定,获得了理想的治疗效果。 相似文献