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21.
在微量注射大量肝脏mRNA之后,通过电压箝方法进行功能鉴定,两栖类卵母细胞成功地表达了AVPV1a受体。但在灌流AV4-8溶液时,却不能诱导卵母细胞产生内向振荡电流反应。提示AVP4-8不能通过AVPV1a受体而介导生理学效应。 相似文献
22.
143例孔源性视网膜脱离临床分析 总被引:1,自引:0,他引:1
本文分析了143例(147眼)孔源性视网膜脱离的一般临床资料、眼部情况、手术类型及治疗结果。本组出院时136眼痊愈(92.5%);随访2月至6年的43眼中34眼痊愈(79.0%)。讨论了视网膜脱离的易发因素、术式选择、手术注意事项和预后。 相似文献
23.
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
24.
用二甲苯所致的急性炎症模型观察了神效止痛膏的抗急性炎症作用.用扭体法、热板法观察了神效止痛膏对小鼠的镇痛作用.结果表明,神效止痛膏有很好的镇痛作用. 相似文献
25.
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
26.
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28.
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
29.
本文探讨食管胃腔内弹力环扎吻合术的力学机理。这是一种不用任何缝合材料或吻合器进行胃食管吻合的新技术,我们已成功应用于临床。取临床所用的乳胶管按该材料多向异性特征、实验条件以及弹力环数目分为8组,每组3个样品进行各种体外力学试验。通过应力—应变(拉力—伸长)关系曲线和定伸长松驰试验确定它的力学特性是一种粘弹性材料。根据实验所得的应力换算为弹力环对食管和胃组织所施加的最佳压力(压强)是4.23±0.23Kg/cm~2,这样才能保证这一种新颖的吻合术可达到简便、安全、可靠的目的。 相似文献
30.
Triploid origin of the gibel carp as revealed by 5S rDNA localization and chromosome painting 总被引:2,自引:0,他引:2
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