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101.
使用自制的微压传感式设备在显微镜下测量甲襞毛细血管压,传感器能精确测出毛细血管血流受阻时的压力,并可自动调零、自动显示和打印。临床使用证明其数据可靠,精确度高且无创,在使用中配以电子半微量天平,保证了仪器的精度、且操作简易,适于临床,优于国外使用的有创性微管插入测压法。  相似文献   
102.
Summary The effects of changes in oxygen supply and oxygen demands on fiber cross-sectional areas, capillary dersities and capillary to fiber ratios were determined in three skeletal muscles of rat. The muscles examined were the vastus lateralis, soleus, and diaphragm. Reduced oxygen supply was produced by subjecting rats to ambient hypoxia, and increased oxygen demands were produced by subjecting rats to low ambient temperatures or treatment with thyroxin. Capillaries were visualized by injecting fluorescent dyes into the circulation. Muscles were quick frozen at resting lengths to preserve normal fiber geometry and were subsequently sectioned on a cryostat. All of the muscles sampled from animals in the experimental groups had elevated capillary densities. However, capillary to fiber ratios were not increased significantly in any muscle, for any experimental condition. Thus, all of the observed differences in capillarity were due to changes in the intrinsic rate of muscle fiber growth. Further, the relations of capillary density and capillary to fiber ratio to fiber area were the same as those obtained during normal maturation, suggesting that capillary growth is closely linked to the intrinsic rate of fiber growth.  相似文献   
103.
Preparations of the nuclear membranes were obtained from purified nuclei of rat liver and hepatoma-27 cells, and from them enzyme-containing extracts of acid-soluble proteins were then prepared. The protein extracts were subjected to disk electrophoresis in 15% polyacrylamide gel. Ribonucleases (RNases) which are constituents of the acid-soluble proteins of the nuclear membranes of normal liver were found to be present as several different components which differed in their electrophoretic mobility and in several physicochemical properties from crystalline bovine RNase and the RNase of nuclear chromatin.Institute of Problems in Oncology, Academy of Sciences of the Ukrainian SSR, Kiev. N. K. Kol'tsov Institute of Developmental Biology, Academy of Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR R. E. Kavetskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 12, pp. 670–672, December, 1977.  相似文献   
104.
本工作应用激光多普勒电泳技术对MA737小鼠乳腺癌细胞膜表面电荷特性及高温(42.5℃)对癌细胞的热效应进行了深入的研究。结果发现,MA737癌细胞的电泳迁移率(EPM)明显高于相应正常细胞的EPM(约20%),表明癌细胞表面负电荷增高;实验发现唾液酸可能是MA737癌细胞膜表主要负电基团的来源之一。研究还发现,MA737癌细胞的热敏性比相应的正常细胞强,随高温受热时间的延长,癌细胞的EPM呈下降趋势。  相似文献   
105.
The discovery of a human myeloma protein comprising a kappa L-chain with an increased mol. wt of 30,000) (Bouvet et. al., 1980) prompted investigations on the incidence of such heavier L-chains among other human myeloma proteins. In 105 samples examined, 34 were found to have L-chains heavier than normal (23,000-24,000), ranging from 25,000 up to 31,000, and five of lighter mol. wt (21,000-22,000). These mol. wt abnormalities were detected by electrophoresis in sodium dodecyl sulfate 10% polyacrylamide gels (SDS-PAGE) after reduction with 2-mercaptoethanol. The mol. wt of three of the heavier kappa or lambda chains was also estimated by filtration through a Sephadex G100 column and by sedimentation equilibrium. All three methods indicated a mol. wt increase of about 15-25% as compared with the usual mol. wt. The distribution of the high mol. wt chains among all L-chains examined was found to be 11 out of 62 kappa chains (17.7%) and 23 out of 43 lambda chains (53%) (P less than 0.001). A preferential association of such L-chains with H-chains producing multiple bands in SDS-PAGE (P less than 0.01) and an association between multiple L-chain and multiple H-chain band (P less than 0.05) were also observed. In contrast, no abnormal L-chain was found in immunoglobulins from normal subjects. Spontaneous degradation of the normal H-chains sometimes yielded fragments of 30,000 mol. wt. These fragments were easily distinguishable from abnormal L-chains. The nature of extra mol. wt in heavy L-chains was investigated for the presence of carbohydrate moiety. Four large and three normal size L-chains were examined for amino-sugar and sialic acid content. A small amount (one residue per molecule) of amino-sugar was detected only in two normal and two heavy L-chains, whereas sialic acid was only found in the heaviest (27,000-30,000) L-chains (Lh) and in small percentage (one or two residues per molecule). Total sugar estimation in one Lh chain indicated a proportion not exceeding three or four residues per L-chain (mol. wt 1,000) and this is insufficient to explain the 15-25% (3,600-6,000) mol. wt increase. It is therefore possible that, at least in some heavy myeloma L-chains, an additional peptide is expressed. Whatever the nature of the increase it would be of interest to elucidate whether this is a marker of malignant process or of an intermediate step of normal Ig synthesis.  相似文献   
106.
Structural and functional studies were performed on a dysfunctional C8 molecule present in the serum of two siblings and an unrelated individual. The C8 in these three sera exhibited a pattern of partial immunologic identity with C8 in normal serum but was devoid of functional activity. The C8 was immunoprecipitated from the three sera and from a control serum with an antihuman C8 antiserum and analyzed by SDS-PAGE using highly purified human C8 as a reference. A selective absence of a band of 62,000 mol. wt was observed in the immunoprecipitates from the sera containing dysfunctional C8. Experiments performed with the purified α-γ and γ subunits showed that the hemolytic activity of the C8 deficient sera could be reconstituted by the addition of the β chain but not the α-γ dimer. Binding of the dysfunctional C8 to C567 was excluded by the following observations: (1) EAC 1–7 treated with the C8 deficient sera and then washed could not be lysed after the addition of the β subunit and C9; and (2) the abnormal molecules did not interfere with the consumption of normal C8 by the soluble complex SC5b-7.  相似文献   
107.
三氧化二砷对肝癌细胞系HepG2生长及核基质蛋白的影响   总被引:8,自引:0,他引:8  
目的 探讨三氧化二砷对人肝癌细胞系HepG2的生长及核基质蛋白的影响。方法 应用生长指数分析和高分辨SDS-聚丙烯酰胺交双向电泳比较用As2O3处理后的HepG2细胞主核基质蛋白的改变。结果 As2O3抑制HepG2的生长,双向电泳显示经As2O3处理后HepG2细胞内出现新的核基质蛋白,并且该蛋白是细胞特异性的。结论 核基质蛋白是某些抗癌药物的作用靶子,As2O3抑帛 癌细胞的生长可望有用于临床  相似文献   
108.
定向克隆构建RAB5A基因真核细胞表达载体   总被引:5,自引:2,他引:3  
目的 探讨RAB5A作为蛋白质人胞信号传导调控者在肿瘤转移中的作用及影响。方法 采用双酶切、定向克隆技术建立了人RAB5A基因真核细胞表达载体pcDNA3.1(-)0RAB5A。结果 测定分析证实了RAB5A基因正向插入pcDNA3.1(-表达载体,免疫组化分析表明转染了pcDNA3.1(-)-RAB5A表达载体的AGZY83-a细胞系细胞内的荧光亮度明显强于转染前,蛋白电泳显示近23KD的蛋白质  相似文献   
109.
目的 :观察新生儿脐血的血液粘度、血浆粘度、红细胞压积、血沉、红细胞电泳情况。方法 :新生儿分娩断脐后立即抽取脐血 4ml+肝素抗凝 ,并立即送检 ,采用北京普利生 L BY- N6 A自清洗旋转式粘度计检验。结果 :母体为正常生理妊娠的新生儿组 :全血低切粘度 8.91± 6 .79m pa· s,全血高切粘度 5 .6 6± 2 .0 mpa· s,血浆粘度 1 .46± 0 .2 4m pa· s,红细胞压积 5 0 .1±1 8.4% ,血沉 2 .1 4± 1 .36 mm/ h,红细胞电泳 1 5 .82± 3.79s;母体为妊高征的新生儿组 :全血低切粘度 1 1 .96± 7.38m pa· s,全血高切粘度 6 .48± 1 .5 7mpa· s,血浆粘度 2 .5 3± 1 6 .4mpa· s,红细胞压积 31 .47± 0 .35 % ,血沉 1 .6 8± 1 .43mm/ h,红细胞电泳1 5 .6 8± 3.43s;正常妇女组 :全血低切粘度 2 2 .33± 6 .88mpa· s,全血高切粘度 4.5 0± 0 .5 4mpa· s,血浆粘度 1 .73± 0 .0 9mpa· s,红细胞压积 41 .0 9± 2 .6 0 % ,血沉 1 7.0 9± 6 .35 mm/ h,红细胞电泳 2 1 .0 4± 1 .44 s。结论 :孕期母体血液流变学变化对新生儿影响较小  相似文献   
110.
  1. Nitric oxide (NO) has been suggested as a gastrointestinal neurotransmitter, mediating the gastric receptive relaxation and the relaxation in the peristaltic reflex. The aim of the present study was to measure nerve-induced NO formation in vivo in the gastrointestinal tract.
  2. Formation of the nitric oxide oxidation products nitrite and nitrate during vagal nerve stimulation were measured in the anaesthetized rabbit. Microdialysis probes were inserted into the wall of the stomach and proximal colon, and nitrite and nitrate in dialysate measured by capillary electrophoresis.
  3. During bilateral vagal nerve stimulation there was an increase in nitrite and nitrate formation at the level of the stomach and in nitrite formation at the level of the colon. This increase was inhibited by intravenous administration of the NO synthase inhibitor Nω-nitro-L-arginine methyl ester (L-NAME 30 mg kg−1). Furthermore, L-NAME significantly increased nerve-induced gastric and colonic contractions, as well as spontaneous colonic contractions.
  4. In summary, we present a new methodological procedure for quantification of small changes in nitric oxide formation in vivo. This study provides evidence that nitric oxide is released in the stomach and colonic wall during vagal nerve activity, at concentrations able to cause inhibition of smooth muscle contractions in vivo.
  相似文献   
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