Echocardiographic evidence of concentric left ventricular enlargement in female weight lifters

In this study we investigated resting left ventricular structure and function in elite female weight-lifters. Fifteen National Squad members [mean age (SD) 25 (6) years] were compared to a recreationally active control group [n = 46, 23 (3) years]. Subjects were matched for body mass, body surface area and fat free mass, but the controls were slightly taller (P<0.01). Athletes and controls demonstrated similar resting heart rates and blood pressures. Septal wall (ST), posterior wall (PWT) and left ventricular internal dimension in diastole and systole (LVIDd and LVIDs, respectively) were measured from M-mode echocardiograms. Calculations were made for left ventricular mass (LVM), mass-volume ratio (m:V), wall-thickness-cavity dimension ratio (h:R) and systolic function. Left ventricular filling velocities were determined via Doppler echocardiography. ST [9.0 (1.1) v.s. 7.7 (1.0) mm] and PWT [8.7 (1.4) v.s. 7.5 (1.3) mm] were greater, whereas LVIDd [46.2 (2.8) v.s. 48.4 (3.4) mm] was smaller in the weight-lifters (P<0.05). After allometrically adjusting for differences in height, the weight-lifters had a greater ST, PWT and LVM (P<0.05) and similar LVIDd. Both m:V and h:R were increased in the weightlifters (P<0.05). All functional data were within normal limits and no group differences were observed. The female weight-lifters demonstrated a concentric left ventricular enlargement that was not detrimental to left ventricular performance at rest.     

Regional Differentiation of Cortical Structures and Their Reorganization during Cell Division in Paramecium trichium

We observed the cell surface of Paramecium trichium using three different methods. A non-dividing paramecium's cell surface consisted of three major regions outside of the oral apparatus: a) an oral groove region, with 2-cilia-2-basal-body (2C-2BB) units; b) a posterior region, occupying 1/4 to 1/5 of the cell surface, with 1-cilium-l-basal-body (1C-1BB) units; c) the remainder, with l-cilium-2-basal-body (1C-2BB) units. Five kinds of region-specific cortical reorganization occurred prior to cytokinesis: the 2C-2BB and 1C-1BB units were not duplicated, while the 1C-2BB units were reorganized to 2C-2BB, 1C-2BB or 1C-1BB units. These reorganizations of the cell surface progressed from the fission line to the anterior in the prospective anterior daughter cell, and to the posterior in the prospective posterior daughter cell, and bilaterally from the old and also newly developing oral apparatus in both daughter cells. In contrast, the development of cilia and their associated structures in each of the cortical units always progressed from posterior to anterior. The present work also showed that two fission lines began to develop bilaterally from the oral primordium, and then they joined to become a single fission line at the dorsal surface.     

单羧酸类Cl-通道阻断剂对心室肌CFTR Cl-通道的影响

本文采用全细胞膜片箝与细胞内灌注技术,观察了单羧酸类Ｃｌ＾－通道阻断剂对豚鼠心室肌囊性纤维变性膜透性调节蛋白（ＣＦＴＲ）Ｃｌ＾－电流的影响,细胞包９－ＡＣ以可逆方式增强异丙肾上腺素（ＩＳＯ）激发的ＣＦＴＲＣｌ＾－的外向电流成分,５－ｎｉｔｒｏ－２－（３－ｐｈｅｎｙｌｐｒｏｐｙｌａｍｉｎｏ）－ｂｅｎｚｏａｔｅ（ＮＰＰＢ）和二苯胺羧酸（ＤＰＣ）对ＩＳＯ发的ＣＦＴＲＣｌ＾－电流的作用呈现先增强后抑制的双     

扩张型心肌病患者LVSI、MHR及Gal-3的临床意义及其与NYHA心功能分级的相关性分析

摘要 目的：研究扩张型心肌病（DCM）患者左心室球形指数（LVSI）、单核细胞计数与高密度脂蛋白胆固醇（HDL-C）比值（MHR）和血清半乳糖凝集素-3（Gal-3）的变化,并分析其与DCM患者心功能的关系。方法：选择2018年1月-2022年10月在我院接受治疗的DMC患者68例作为研究组,并选取同期50例健康体检者作为对照组。研究组患者根据出院6个月份是否发生主要不良心血管事件分为MACE组和No-MACE组。比较各组间左心室射血分数（LVEF）、左心室舒张末期内径（LVEDD）、左室收缩末期内径（LVESD）、LVSI、单核细胞计数、HDL-C、MHR以及血清Gal-3。结果：（1）研究组患者LVEF显著低于对照组,而研究组患者LVEDD、LVESD以及LVSI均显著高于对照组（P<0.05）。（2）研究组患者单核细胞计数、HDL-C、MHR以及Gal-3均显著高于对照组（P<0.05）。（3）不同心功能分级DCM患者LVEF、LVEDD、LVESD、单核细胞计数和HDL-C组间比较无显著差异（P>0.05）,但LVSI、MHR和血清Gal-3组间比较差异显著（P<0.05）。（4）MACE组患者LVSI、MHR和Gal-3均显著高于No-MACE组患者（P<0.05）。结论：LVSI、MHR和血清Gal-3在扩张型心肌病患者中升高,并与患者心功能分级有关,可作为DCM患者心功能恶化评价指标。     

水稻中央细胞发育期间超微结构变化的观察

本文通过透射电镜对水稻受精前胚囊中央细胞发育过程中超微结构的变化进行观察。结果表明,八核胚囊形成后很快就进行细胞化形成7个细胞,其中刚形成的中央细胞由1个大液泡、2个极核（珠孔端和合点端各1个）和一些含有丰富细胞器的胞质组成。中央细胞以后的发育主要是极核的发育和极核周围胞质的变化。极核发育经历以下过程：a．2个核都膨大呈“椭圆”形。核周围胞质呈不对称分布。b．2个核分别向胚囊中央移动并相互靠近。之后2个极核调整排列方式,由纵排（即与胚囊纵轴平行）变成横排。此时期有细胞质“桥”联结珠孔端卵器、2个极核和合点端反足细胞器。c．横排的极核移向卵器,并排列于卵细胞之上。此时胚囊未明显膨大,但极核相靠近的两边核膜有许多处已形成“融合桥”,核周围的胞质也起较大的变化,如质体内淀粉消失和光面内质网增加等。极核进一步发育直至胚囊成熟期间,极核排列方式及其周围胞质组成未观察到明显的变化,但胚囊体积明显增大。     

巯甲丙脯酸降低缺血再灌注心律失常的发生率

本工作用放射免疫法、荧光组织化学等方法探讨心肌儿茶酚胺和前列环素在大鼠缺血再灌注心律失律失常发生中的作用。结扎左冠状动脉造成局部心肌缺血然后再灌注。在缺血再灌注组,缺血再灌注引起的心室纤颤发生率为７８％;在巯甲丙脯酸组,巯甲丙脯酸预处理可使缺血再灌注心室纤颤发生率下降了６５．５％;与缺血再灌注组相比,巯甲丙脯酸组的心肌儿茶酚胺含量、心肌６－酮－ＰＧＦ１ａ（６－Ｋｅｔｏ－ＰＧＦ１ａ）的含量明显升高（     

急性低氧对大鼠血粘度,红细胞变形能力和左心室功能的影响

健康ＳＤ雄性大鼠,体重２５０—３００ｇ,麻醉、气管插管,用人工呼吸机经气袋供气,自发吸入氧浓度为９％的氧氮混合气,用ＳＭＵＰ－ＰＣ生物信号处理系统处理左心室功能。结果：（１）急性低氧经动脉血气分析可见ＰａＯ２下降（Ｐ＜０．０１）,ｐＨ值升高（Ｐ＜０．０５）,ＰａＣＯ２稍下降（Ｐ＞０．０５）,左心室功能各指标如ＬＶＰ,ＨＲ,Ｖｍｐ,±ｄｐ／ｄｔｍａｘ,Ｖｃｅ４０,Ｖｍａｘ,Ｌ０、等均下降;血液流变学指标如全血粘度（高、低切值及其还原值）升高,红细胞滤过指数（ＩＦ）升高;复氧后上述各指标恢复正常。（２）静脉注射心得安（０．５ｍｇ／Ｋｇ）后,使急性低氧诱发的左心室功能各指标更加明显下降,而血液流变学各值不再明显上升;静脉注射酚妥拉明（３ｍｇ／Ｋｇ）后,使急性低氧诱发的血液流变学各值上升不明显。（３）石炭酸破坏双侧颈动脉窦区后也可致低氧诱发的左心室功能各指标进一步下降,而血液流变学指标也不再明显上升。结果提示：急性低氧可引起左心室功能下降和全血粘度升高,红细胞变形能力降低,复氧后可恢复;交感神经活动及颈动脉窦区化学感受性反射可能对抗低氧诱发的左心室功能的下降,促进血粘度的升高。     

Ultrastructural characterization of apospory in Panicum maximum

The nucellar ultrastructure of apomictic Panicum maximum was analyzed during the meiocytic stage and during aposporous embryo sac formation. At pachytene the megameiocyte shows a random cell organelle distribution and sometimes only an incomplete micropylar callose wall. The chalazal nucellar cells are meristematic until the tetrad stage. They can turn into initial cells of aposporous embryo sacs. The aposporous initials can be recognized by their increased cell size, large nucleus, and the presence of many vesicles. The cell wall is thin with few plasmodesmata. If only a sexual embryo sac is formed, the nucellar cells retain their meristematic character. The aposporous initial cell is somewhat comparable to a vacuolated functional megaspore. It shows large vacuoles around the central nucleus and is surrounded by a thick cell wall without plasmodesmata. In the mature aposporous embryo sac the structure of the cells of the egg apparatus is similar to each other. In the chalazal part of the egg apparatus the cell walls are thin and do not hamper the transfer of sperm cells. Structural and functional aspects of nucellar cell differentiation and aposporous and sexual embryo sac development are discussed.     

An ultrastructural study of early endosperm development and synergid changes in unfertilized cotton ovules

Excised, unfertilized cotton (Gossypium hirsutum L.) ovules were cultured for 1–5 days postanthesis and embryo-sac development was studied with the electron microscope. In some ovules the two polar nuclei fuse and the diploid endosperm nucleus goes through a limited number of free nuclear divisions after 2–3 days in culture. Each nucleus has two nucleoli, in contrast to nuclei of fertilized triploid endosperm which have three nucleoli. Precocious cell walls form between the endosperm nuclei on the 3rd day in culture. The morphology of the plastids, mitochondria, rough endoplasmic reticulum (RER), dictyosomes and microbodies, and the amount of starch and lipid in the diploid cellular endosperm are similar to those of the central cell. A few large helical polysomes appear close to plastids and mitochondria. After 2 days in culture, one of the two synergids in the unfertilized cultured ovules shows degenerative changes which in fertilized ovules are associated with the presence of the pollen tube, i.e., increase in electron density, collapse of vacuoles, irregular darkening and thickening of mitochondrial and plastid membranes, disappearance of the plasmalemma and the membranes of the plasmalemma and the membranes of the RER. The second synergid remains unchanged in appearance. The egg cell does not shrink or divide or show structural changes characteristic of the cotton zygote. Embryo-sac development is arrested on the 4th and 5th days in culture. The nucellus continues growth and at 14 days crushes the degenerate embryo sac.     

五唇兰未受精胚珠离体培养及雌配子体发育的研究

五唇兰(Doritispulcherrima Lindl.)的胚珠属于倒生型,具薄珠心,两层珠被.胚囊发育类型为双孢子葱型,授粉后约45 d形成七细胞八核的成熟胚囊.五唇兰未受精胚珠在离体培养初期对外源激素的依赖性很小,在没有外源激素的培养基上,大孢子母细胞也能经过减数分裂发育为二核胚囊.在培养后期,外源激素对胚囊发育的影响很大.在培养基无外源激素或仅含生长素或细胞分裂素时,雌配子体的发生过程不能顺利完成;在改良VW培养基上添加0.5 mg/L BA和0.1 mg/LNAA时,形成成熟胚囊.