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11.
硒和/或维生素E预防大鼠内皮细胞损伤的实验研究   总被引:15,自引:1,他引:14  
蔡梅雪 《营养学报》1997,19(2):163-166
用含硒(Se0.5mg/kg)和/或维生素E(VE0.6g/kg)的高脂饲料喂养成年雄性Wistar大鼠12周。结果:高脂对照组大鼠血浆前列腺素Flα(6-酮-PGF1α)水平下降,而血清脂质过氧化物(LPO)、血浆血栓素(TXB2)及内皮素(ET)水平上升;补Se、VE及Se+VE可明显降低大鼠血清LPO、血浆TXB2、ET及TXB2/6-酮-PGF1α比值。同时,除了明显提高血浆谷胱甘肽过氧化物酶(GSH-Px)活力外,血浆6-酮-PGF1α浓度明显升高。实验提示,Se和/或VE有调节花生四烯酸代谢及保护内皮细胞的作用。  相似文献   
12.
足组织缺损的显微修复   总被引:15,自引:11,他引:4  
1984年~1994年共收治各种足部组织创伤缺损236例,均采用显微外科技术进行组织移植修复,其中单纯皮瓣移植修复187例,复合皮瓣移植修复49例。吻合血管游离移植修复97例,带血管蒂移位修复139例。4例前足缺损者用带肩胛骨的复合皮瓣移植修复,6例足跟严重缺损者用带血管的腓骨复合皮瓣移植修复。经1~10年随访,皮瓣、复合皮瓣、移植或再植的骨骨各全部成活,愈合良好,足功能基本得到恢复,可行走、负重,186例恢复了原工作。认为,恢复足部结构完整与重建足跟、足底的感觉是获得良好功能的关键  相似文献   
13.
Gerbils are much more sensitive to the hepatotoxic and lethal effects of CCl4 than rats as indicated by 48-hr LD50 values (0.08 vs 2.8 ml/kg). On the other hand, gerbils are refractory to chlordecone (CD) potentiation of CCl4 toxicity. To investigate the possible mechanism underlying the high sensitivity of gerbils to CCl4 lethality, the metabolism of CCl4 was studied in gerbils pretreated with dietary CD, phenobarbital (PB), or mirex (M) at 10, 225, and 10 ppm, respectively. The hepatic content of 14CCl4, the expiration of 14CCl4 and 14CCl4-derived 14CO2, and lipid peroxidation were measured and the results were compared with the previous data for rats. After the 15-day dietary pretreatment, male gerbils (60-80 g) received 14CCl4 (0.08 ml/kg; sp act 0.04 mCi/mmol) ip in corn oil and the radioactivity present in the expired air was collected for 6 hr. More than 80% of the parent compound as represented by the 14C-label in the toluene trap was expired in 6 hr regardless of the pretreatments. Expiration of 14CO2 measured during the 6 hr after 14CCl4 administration in control gerbils was 3.5-fold more than that in rats and was significantly increased in pretreated groups (M greater than PB greater than CD). PB and M pretreatments resulted in a significant increase of 14C-label bound to the nonlipid fraction of the liver as compared with CD-treated or control gerbils. The radiolabel present in the livers of control gerbils was 5-fold higher than that of rats. In vivo lipid peroxidation measured as diene conjugation in lipid extracts from the livers was lower in gerbils than in rats, and none of the pretreatments significantly affected lipid peroxidation. The serum alanine aminotransferase and aspartate aminotransferase were significantly elevated at 6 hr after CCl4 injection in all groups of gerbils. These data indicate that the more extensive metabolism of CCl4, as represented by 14CO2 formation and 14C-label bound to hepatic tissue, in gerbils as compared with rats, may partially explain the high sensitivity of gerbils to CCl4 toxicity. However, the enhanced metabolism of CCl4 found in CD-, PB-, or M-pretreated gerbils did not lead to amplified hepatotoxic and lethal effects of CCl4. The reason gerbils may be refractory to CD amplification of CCl4 injury might be associated with other factors yet to be investigated.  相似文献   
14.
常才  朱关珍 《生殖与避孕》1994,14(3):193-197
本研究采用先进的三维超声成像技术及多普勒技术对正常育龄妇女月经周期中心血管功能进行研究。结果:月经周期中HR、BP无变化;血清E2是周期性变化,排卵前达高峰。SV、CO、EF在排卵前期升高达峰值,显著高于月经期和黄体期;SVR排卵前期最低,而Ved、Ves无变化。Vmax、A、E在内源性E2高峰时明显加快,而E/A比值无明显变化。结果提示:月经周期中随内源性E2的周期性变化,心脏功能也发生周期性变化。E2高峰时,心输出量、心搏量和射血分数达最高。外周阻力最低,心脏内血流速度加快。  相似文献   
15.
采用 TAD 方案治疗急性非淋巴细胞性白血病(ANLL)12例,年龄17~47岁。总有效率为66.7%,完全缓解率(CR)为41.7%。5例获 CR 的时间是26~66天,平均53天,较国内其它方案为快。CR 时间为2~9月,平均6.2月,较其它方案又较短。TAD 方案对心脏的毒性作用轻微。TAD 方案对5例获 CR 者,于诱导治疗第一疗程后,除1例外,骨髓中白血病细胞百分比下降均不明显;但于第二疗程后,白血病细胞全部减少到骨髓有核细胞总数的20%/以下,这种现象似可作为本方案预后的观察指标。  相似文献   
16.
CCN家族研究进展   总被引:3,自引:0,他引:3  
新近发现的CCN基因家族包括CTGF,Cyr61,nov,elml,HICP和WISP-3等,它们由343-381个氨基酸残基构成4个结构模块,都含有38个保守的半胱氨酸,具有广泛的生物学特性,影响细胞的生长,分化,粘附和运动,在妊娠,发育和分化,血管生成,伤口修复,炎性作用,肿瘤生长等多种生物学过程中起重要作用。  相似文献   
17.
18.
The plasma endothelin (ET) level in spontaneously hypertensive rats (SHR) and 2K1C hypertension animal models and its vasoconstrictive effect on renal and tail arteries were studied. The results demonstrated that there was no difference in plasma ET level between the hypertensive groups SHR, 2K1C, normotensive control groups Wistar Kyot (WKY) and Sprague Dawley (SD), while the vasoconstrictive effect of ET in SHR was more dominant than in WKY. The EC50 of the renal and tail arteries in SHR (0.8912 +/- 0.1662 x 10(-8) M, 0.6103 +/- 0.0878 x 10(-8) M) was apparently lower than that in WKY (1.77 +/- 0.2991 x 10(-8) M, 1.2267 +/- 0.2502 x 10(-8) M, P less than 0.05), but no difference was found in 2K1C and SD rats. The four groups of animals exhibited no difference of such effects as response to norepine-phrine (NA). The findings suggested that the increased arteriole sensitivity to ET be an important factor in the pathogenesis of hypertension in SHR.
  相似文献   
19.
本文对不同人群抽样调查1101人,结果鼻咽部金葡菌带菌者222人。其中医务人员和住院患者的金葡菌带菌率明显高于院外人群(P<0.001)。提示医院内存在交叉感染。对222株金葡菌测定药敏试验及β-内酰胺酶,结果β-内酰胺酶阳性率89.6%。产酶株全部对青霉素耐药,不产酶株对青霉素敏感率91.4%。产酶与否,对红霉素、氯霉素耐药严重。利福平、苯唑青霉素、丁胺卡那霉素对金葡菌有极高的抗菌活性。  相似文献   
20.
The characteristic distribution of calcitonin gone-related peptide(CGRP)inthe small intestine of rats and its changes in acute intestinal radiation sickness(AIRS)were studied with immunocytochemistry(whole mount stretch preparations of the smallintestine and cryostat sections)and radio-immunoassay.It was found that in all the lay-ers of the intestinal walls,there were large amounts of CGRP immunoreactive(CGRP-I)nerve fibers which existed in especiaUy high density in the myenteric,submucosal andmucosal plexuses.There was also a rather high density of the nerves around the smallvessels of the small intestine and the intestinal crypts.Some CGRP-I neurons were seenin the myenteric and submucosal plexuses.In AIRS,the intestinal CGRP showed a dip-hasic change,in a lower level in the 24th h and a higher level in the 48th and 72nd h af-ter irradiation.The results indicate that CGRP may be related to the regulation of the motility,se-cretion,absorption,sensation,and regional blood flow of the gastrointestinal tract.Pro-bably,CGRP is released under the stress of AIRS and participates in the mechanism ofinjury through many ways especially through the influence on the regional blood flowand the increase of the permeability of blood vessels.  相似文献   
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