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1.
Summary The bovine lens capsule has previously been shown to provide an optimal surface for the examination of epithelial cell interaction with a basement membrane. This native substrate has been used to investigate some initial aspects of attachment of mouse blastocysts and trophoblastic cellular outgrowth. Mouse blastocysts were presented to the cell-free humoral side of the anterior lens capsule, incubated for 72 h, and examined by scanning and transmission electron microscopy. Blastocysts hatch and attach from their zonae pellucidae by 30 h. Trophoblastic cells proliferate rapidly in a coronal direction, display extensive surface microvilli, and advance by the extension of numerous filipodia, many of which terminate with bulbous projections. These projections were shown by transmission electron microscopy to contain numerous vacuoles and polysomes. To simulate further the initial blastocyst-uterine interaction, a suspension of lens epithelial cells was introduced to the capsule and permitted to form a monolayer prior to the addition of the blastocysts. At 72 h the monolayer of lens cells remained intact. We observed that: a) lens cells appear to recede from the advancing trophoblastic cells, and b) trophoblastic cells extend beneath the monolayer of lens cells and thereby dislodge the cells from the lens capsule substrate. No infiltration of the capsule by the advancing trophoblastic cells was observed. The lens capsule appears to offer a promising system for the study of trophoblast-epithelial cell interaction on a natural basement membrane.  相似文献   
2.
The rewardless orchid Dactylorhiza sambucina shows a stable flower colour polymorphism, with both yellow- and red-flowered morphs growing sympatrically. Pollination biology and breeding system were investigated to examine the effects of density of plants, colour polymorphism, inflorescence dimension, and flower position within inflorescence on male and female reproductive success in three natural populations of D. sambucina. There were significant differences among sites in the number of pollinia removed and in fruit set per inflorescence. Number of removed pollinia and capsule production in D. sambucina were independent from flower and inflorescence size or flower position. As a whole, the red morphs showed the highest number of capsules produced, while the yellow morphs had the greatest male success. The relative male and female reproductive success were independent from plant density but were significantly correlated with the yellow morph frequency at the population level. Overall, our findings show that the contribution to the total reproductive success deriving from the two colour morphs does not conform with the predictions of negative frequency-dependent selection.  相似文献   
3.
犬脑11只,经生理盐水冲洗脑血管后,注入20%钡胶液,切成0.2~1.0厘米的厚片,用显微X线法研究犬脑内各级动脉的构筑,其结果:1.皮质动脉的管径平均为25.9±0.005微米,平均长度为888.0±0.241微米。其形态与发出部位有关,分别呈栅状和瓶刷状。2.髓质动脉的管径平均为49.9±0.007微米。呈直线或孤形向心走行。3.皮质下动脉的管径平均为38.7±0.009微米。呈新月形或蟹钳状分布。4.豆纹动脉和内囊动脉的平均管径为70.0±0.021微米。呈锐角、反血流方向发自母干,再呈“S”形上升。5.丘脑动脉的平均管径为63.7±0.019微米,主要从下方进丘脑,呈树枝状分支。  相似文献   
4.
R. H. Berg 《Protoplasma》1990,159(1):35-43
Summary Enzyme-gold affinity labeling was used to show that in mature infected cells of actinorhizal symbioses the capsule on the plant host side of the symbiotic interface contained cellulose and xylans. Host species examined for cellulose wereAlnus rubra, Casuarina equisetifolia, C. glauca, Ceanothus cuneata, C. velutinus, Elaeagnus pungens, andMyrica cerifera.. Cellulose was in the capsule throughout the infected cell, implying that during development cellulose synthase was present in the host cell membrane component of the symbiotic interface. Any possible degradation of capsule cellulose by the microsymbiont was either incomplete or transient, because the polymer was present in mature infected cells. Cellulose labeling inCeanothus andElaeagnus was less consistent than in the other species. Dual labeled capsules inCasuarina glauca andAlnus rubra showed a similar distribution of xylans and cellulose. Cytochemical studies indicate that the capsule contains three major classes of cell wall polysaccharides: cellulose, hemicellulose (xylans), and pectins (shown previously). This suggests that the capsule is essentially a thin, internal, tubular plant cell wall.Abbreviations Au5 Au15 colloidal gold particles with mean diameter of 5 and 15 nm, respectively - CBHI cellobiohydrolase I - CBHII cellobiohydrolase II - PBS phosphate-buffered saline  相似文献   
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6.
摘要 目的:探讨枸橼酸托法替布片联合仙灵骨葆胶囊对类风湿性关节炎(RA)合并骨质疏松患者血清炎症细胞因子、骨强度及骨代谢水平影响。方法:纳入2021年8月至2022年8月期间徐州医科大学附属连云港医院诊治的80例RA合并骨质疏松患者。根据随机数字表法将患者分为对照组(雷公藤多苷片联合仙灵骨葆胶囊治疗)和实验组(枸橼酸托法替布片联合仙灵骨葆胶囊治疗),各为40例。对比两组疗效、炎症细胞因子、骨强度及骨代谢指标,观察两组不良反应发生率。结果:实验组的临床总有效率高于对照组(P<0.05)。实验组治疗后巨噬细胞集落刺激因子(M-CSF)、白细胞介素-1β(IL-1β)、环氧合酶-2(COX-2)低于对照组同期(P<0.05)。实验组治疗后横截面积(CSA)、横截面转动惯量(CSMI)、截面系数(Z)、皮质厚度(CT)高于对照组同期(P<0.05)。实验组治疗后骨钙素N端中分子(N-MID)、总Ⅰ型胶原氨基端延长肽(T-PINP)、骨钙素(BGP)、Ⅰ型胶原羧基端前肽(PICP)高于对照组同期,β-胶原降解产物(β-CTX)低于对照组同期(P<0.05)。两组治疗后腰椎骨密度和股骨颈骨密度较治疗前升高,且实验组高于对照组同期(P<0.05)。两组治疗后血沉(ESR)、C反应蛋白(CRP)、类风湿关节炎患者病情(DAS28)评分下降,且实验组低于对照组同期(P<0.05)。两组不良反应发生率组间对比无统计学差异(P>0.05)。结论:枸橼酸托法替布片联合仙灵骨葆胶囊应用于RA合并骨质疏松患者,可有效调节骨代谢水平,增强骨强度,降低血清炎症细胞因子水平。  相似文献   
7.
摘要 目的:探讨心元胶囊对慢性心力衰竭(CHF)心血瘀阻证患者心脏超声参数、脂质代谢及血液流变学的影响。方法:根据随机数字表法,将我院2020年3月~2022年3月期间收治的的CHF心血瘀阻证患者120例分为对照组(常规西药治疗,n=60)和观察组(心元胶囊联合常规西药治疗,n=60)。对比两组中医疗效、心功能指标、血脂指标、肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)、N-末端脑钠肽前体(NT-proBNP)、血液流变学指标,并观察两组不良反应情况。结果:观察组的中医总有效率明显高于对照组(P<0.05)。两组治疗后左室射血分数升高,左室舒张末期容量、左室收缩末期容量缩小,且观察组的改善效果优于对照组(P<0.05)。两组治疗后三酰甘油(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)下降,高密度脂蛋白胆固醇(HDL-C)升高,且观察组的改善效果优于对照组(P<0.05)。两组治疗后CK、CK-MB、NT-proBNP下降,且观察组的改善效果优于对照组(P<0.05)。两组治疗后全血高切黏度、全血低切黏度、血浆黏度、纤维蛋白原下降,且观察组的改善效果优于对照组(P<0.05)。两组不良反应发生率对比,差异无统计学意义(P>0.05)。结论:心元胶囊治疗CHF心血瘀阻证可提高临床疗效,改善心功能,调节脂质代谢、血液流变学水平,安全有效。  相似文献   
8.
The albumen gland of Pomacea paludosa, a prosobranch gastropod, contains two main ducts. The albumen gland duct consists of a single layer of secretory and non-secretory cells. The surface of the non-secretory cells is covered with cilia. Microvilli are associated with the luminal edges of the secretory cells. Globules of secretory products appear at the cell surfaces. The capsule gland duct coils through the albumen gland and is composed of two opposing faces each of two layers of cells. The upper layer consists of ciliated non-secretory cells and the microvilli covered necks of the goblet-shaped secretory cells. The bases of the secretory cells comprises the lower layer of cells. Differences in the arrangement of cellular processes and number exists between the duct epithelia.  相似文献   
9.
本文应用分支系统学原理对鳅(鱼它)鱼类的鳔囊、鳔及相关结构进行了特征分圻,并以(鱼句)亚科作为外类群。解剖结果表明,鳅(鱼它)鱼类的鳔分四种类型;分析结果进一步证实鳅(鱼它)鱼类是一个单源群,作为一亚科可分为异鳔鳅(鱼它)属和鳅(鱼它)属,后者又分为原鳅(鱼它)和鳅(鱼它)二个亚属。  相似文献   
10.
Summary The intercellular connections between the epithelial cells of Bowman's capsule were investigated. It could be demonstrated that typical zonulae occludentes (tight junctions) are present in the species (rat, hamster, and Tupaia) studied. Freeze-fracturing shows a network of anastomizing strands; some species variations are described. In the rat two strands are common. In the golden hamster mostly two to four and occasionally five strands occur. In Tupaia regularly three tight junction strands are found and also gap junctions associated with the zonulae occludentes. In thin sections the goniometric analysis confirms the freeze-fracturing results and reveals attachment zones of macular shape, which are classified as intermediate junctions and desmosomes. The functional role of these cell junctions observed in the epithelium of Bowman's capsule is discussed.  相似文献   
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