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11.
大鼠自体异体表皮细胞悬液混合移植的实验研究   总被引:3,自引:2,他引:1  
目的 探讨自、异体表皮细胞悬液混合移植技术在创面修复中的应用。 方法  30只大鼠随机配成 15对后 ,分成细胞悬液移植组 (A组 ,10对 )和细胞膜片移植组 (B组 ,5对 )。取每只大鼠全厚皮 ,分离表皮细胞 ,并根据配对情况按 1∶1的细胞比例混合 ,体外常规培养。 4d后收获A组混合细胞悬液 ,14d后收获B组混合细胞膜片。将此细胞悬液和膜片分别转移至A、B组相应供体大鼠的去全厚皮创面。随后A组每对大鼠的创面交叉覆盖配对方的异体全厚皮 ;B组创面覆盖胶原膜及“优妥”敷料。比较移植后 2~ 3周两组的创面修复情况。 结果 术后 2~ 3周 ,A组创面大多愈合 ,表面光滑 ,与皮下连接紧密。术后第 5天 ,B组创面部分细胞膜片脱落 ,部分成活 ,膜片成活的创面后期再次出现小创面 ,经久不愈。 结论 自、异体表皮细胞悬液混合移植是一种可行的、体内构建皮肤、修复创面的方法。  相似文献   
12.
Da-Nian Zhu, Long-Mei Xue, Peng Li. Effect of central muscarine receptor blockade. with DKJ-21 on the blood pressure and heart rote in stress-induced hypertensive rats.

The experiments were performed on Wistar or Sprague-Dawley rats of both sexes divided at random into stress and control groups. The rats in the stress groups were put into cages and subjected to electric foot-shocks and noises for 9-15 days, which caused an increase in blood pressure (BP) and heart rate (HR). In hypertensive rats DKJ-21 (4mg/lml) was injected intravenously (i.v.), and 0.5-1.0h after administration the BP and HR dropped from the high level to normotensive level. In normotensive rats, however, administration of DKJ-21 had no effect on BP or HR. In separate groups of normotensive rats, pretreatment of DKJ-21 (4 mg/l ml, i.v.) blocked the pressor and tachycardiac effect induced by microinjection of physostigmine (0.4μg/0.1 /μl/site), corticosterone (40μg/0.1μl/site) or aldosterone (40 μg/0.1 μl/site) into the rostral ventrolateral medulla (rVLM). Furthermore, DKJ-21 also attenuated the enhancement of the pressor response to stimulation of the defense area in the midbrain, which was induced by microinjection of drugs (mentioned above) into the rVLM. These results indicate that i.v. DKJ-21 can selectively block the muscarinic receptors in the rVLM in stress-induced hypertensive rats, which suggests that abnormal enhancement of cholinergic mechanism in the rVLM may be related to hypertensive effects of corticoids in this area.  相似文献   
13.
Conventional computerized tomography (CT) technique is based on the absorption contrast. In recent years, X-ray phase-contrast CT (PCCT) has been developing rapidly. It uses the phase information to reconstruct the object and provide high contrast and spatial resolution. Diffraction enhanced imaging (DEI) method is one of the three phase-sensitive X-ray imaging techniques. DEI method employs an analyzer crystal to extract the object's refraction information which can be used for CT. However, when DEI refraction CT is combined with the conventional CT algorithm, it should be satisfied that the refraction information of an arbitrary point in the object is invariable at every projection view. In this paper, the invariance condition of refraction information is analyzed and two feasible methods are provided for reconstruction. Using these two methods, two samples of weak absorption are reconstructed with the experimental data obtained at Beijing Synchrotron Radiation Facility (BSRF).  相似文献   
14.
Summary In this study the technique of labelling the cell membrane with DPH fluorescence polarization was used to observe the membrane fluidity of B lymphocytic cell lines and tonsillar cells from healthy persons; the modulation effect on membrane-fluidity induced by McAbs against isotypic and idiotypic determinants of IgM from patients with leukemia was studied as well. The expression of the corresponding isotypic and idiotypic determinants of IgM on the cell membrane was determined. The results show that the membrane fluidity of leukemic cell lines is remarkably higher than that of tonsillar cells from healthy persons, and McAbs against isotypic determinants of leukemic IgM can enhance the membrane fluidity of all kinds of cells mentioned above. However, the anti-idiotypic monoclonal antibody increased only the membrane fluidity of leukemic cell lines. These results indicated that there was a close relationship between the effect of McAbs on cell membrane fluidity and the expression of corresponding isotypic and idiotypic determinants of IgM on the cell membrane.  相似文献   
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X Y Zhu  H Y Yu 《中西医结合杂志》1990,10(8):485-7, 454
The immunosuppressive effect of cultured Cordyceps sinensis (Bei Lin Capsule) was studied in vitro and in vivo. When the drug was added from 0.6 mg/ml to 5 mg/ml a significant dose-dependent inhibition effect was shown in the following immune reactions of mice (P less than 0.05-0.01): phagocytic function of peripheral blood leucocytes assayed by chemiluminescence; mitogenic response of spleen lymphocytes to Con A; mixed lymphocyte culture and LPS induced interleukin-1 release of macrophages. The survival rate of mice spleen lymphocytes cultured with Cordyceps sinensis 5 mg/ml in 37 degrees C 5% CO2 for 5 days was more than 80%. Cordyceps sinensis 4 g/kg daily significantly prolonged the mice skin allograft survival time (12.7 +/- 2.2 days v.s. 8.3 +/- 0.7 days in the control, P less than 0.01) and its immunosuppressive effect was close to that of Cyclosporin A 5 mg/kg daily on skin allograft.  相似文献   
18.
5S ribosomal DNA (rDNA) was isolated and sequenced from the gibel carp Carassius auratus gibelio with 162 chromosomes and crucian carp Carassius auratus with 100 chromosomes, and fluorescent probes for chromosome localization were prepared to ascertain the ploidy origin and evolutionary relationship between the two species. Using fluorescence in-situ hybridization (FISH), major 5S rDNA signals were localized to the short arms of three subtelocentric chromosomes in the gibel carp and to the short arms of two subtelocentrics in the crucian carp. In addition, some minor signals were detected on other chromosomes of both species. Simultaneously, six chromosomes were microdissected from the gibel carp metaphase spreads using glass needles, and the isolated chromosomes were amplified in vitro by degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR). Significantly, when the DOP-PCR-generated probes prepared from each single chromosome were hybridized, three same-sized chromosomes were painted in each gibel carp metaphase, whereas only two painted chromosomes were observed in each crucian carp metaphase spread. The data indicate that gibel carp is of triploid origin in comparison with diploid crucian carp.  相似文献   
19.
L Zhu  R K Crouch 《Cornea》1992,11(6):567-572
The action of hydrogen peroxide on soluble proteins of the rat cornea has been evaluated. Two major corneal proteins are found to be oxidized by 10 mM hydrogen peroxide. Protein sequence and antibody recognition has shown one of the proteins to be albumin. Treatment of pure rat or human albumin with hydrogen peroxide oxidizes the protein and decreases its affinity for its antibody. Because albumin is a major protein in the cornea, its ready oxidation suggests that a role for albumin in this tissue may be to act as a native antioxidant, scavenging hydrogen peroxide and thus preventing more extensive damage by this toxin. These data are relevant to the evaluation of the safety of contact lens disinfectants containing hydrogen peroxide and suggest that further study of the action of this oxidant is warranted.  相似文献   
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