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31.
During passage of hamster spermatozoa through the epididymis their maturation is shown to involve changes in the sperm head, midpiece (mitochondria) and tail. The sum of these changes results in a dramatic increase in the fertilizing potential of the spermatozoa. When comparable numbers of spermatozoa from the caput or corpus epididymis were injected into one uterine horn of mature females, following ovulation induction, and spermatozoa from the cauda epididymis were injected into the contralateral horn, no fertilization was observed with caput epididymal spermatozoa, 1.7% of oocytes were fertilized by corpus epiddymal spermatozoa, whereas 79.5% fertilization was obtained with cauda epididymal spermatozoa. Total sperm numbers increased from caput to corpus to cauda [28.3 ± 12.2, 40.6 ±20.8, 1434 ±62 mihon, respectively]. The percentage of progressively motile spermatozoa increased from 27.9 ±6.4 to 33.8 ± 4.8 to 70 ± 10.7 during this passage. Viability, measured by exclusion of the dye, propidium iodide, was significantly less in spermatozoa from the cauda than from the proximal or mid-caput epididymis. The percentage of the live cells that were stained intensely by rhodamine-123 (a measure of mitochondrial membrane potential) increased during epididymal passage from 22.8 ±7.8% in the proximal caput epididymis to 57.2 ± 16.5% in the cauda epididymis. Staining with acridine orange (a measure of DNA packaging in the sperm head) indicated an increase in chromatin condensation in cauda epididymal spermatozoa, when compared to those obtained from the caput or corpus.  相似文献   
32.
Summary In the presented study, knee joint proprioception of 43 patients with a patellar pain syndrome of the knee joint was evaluated. In a control group, the proprioception of 30 healthy volunteers with clinical and anamnestic inconspicous knee joints was examined. We tested the proprioceptive capability of the subjects with a passive angle reproduction test. Additionally, all knee joints were measured with and without an elastic knee bandage. The patient group showed significant deterioration of angle reproduction capability (13.2 °± 6.1 °) compared to the control group (7.8 °± 2.8 °). After applying an elastic knee bandage, the angle reproduction capability significantly improved to 9.2 °± 4.5 °. Proprioception of the contralateral, noninvolved knee joint in the patients (11.6 °± 6.3 °) was worse compared to the control group. Applying an elastic knee bandage did not significantly improve the proprioception of the uninjured knee joint.   相似文献   
33.
In isolated rat lungs subjected to fat emulsion damage, a model simulating adult respiratory distress syndrome, we have previously reported that adenosine (ADO) reduces pulmonary vascular resistance (PVR) and the fluid filtration rate (FFR). In the present study the aim was to examine morphologically this effect of ADO. Two groups of isolated rat lungs were subjected to the injury. Marked and significant differences were found between the groups; in lungs not given ADO, FFR and airway pressure were higher and, as evaluated by electron microscopy, the endothelial lining was thin and partly disrupted. The epithelial cells of the alveolar walls were also partly disrupted and the alveolar septa were split enclosing interstitial edema. In lungs receiving ADO from the onset of exposure to fat emulsion, FFR was lower and ultrastructure did not differ from non–injured non–treated controls perfused for the same length of time.  相似文献   
34.
The detection of some types of aneuploidy in human spermatozoacan be based on the use of the fluorescence in-situ hybridizationtechnique (FISH). One of the crucial steps for FISH is to achievea proper decondensation and denaturation of the DNA in the specimen,so as to obtain efficient hybridization results. However, afterDNA decondensation the morphology of sperm heads is partly distortedand the majority of the tails is lost. This situation leadsto problems in the distinction between disomic and diploid spermatozoa,as well as between abnormal spermatozoa and somatic cells. Double-and triple-target FISH can partly solve this discriminationproblem. To improve these procedures we adapted the steps ofdecondensation and visualization of the single sperm cells.Firstly, DNA decondensation with 25 mM dithiothreitol in 1 MTris at pH 9.5 resulted in sperm cells with intact morphologyof both the head and the tail, and allowed efficient single-,double- and triple-target ISH to be performed. Secondly, weapplied a novel detection method, based on enzyme immunocyto-chemicalreactions, with coloured precipitation products. Thirdly, thisISH procedure was combined with Diff-Quik staining and bright-fieldmicroscopy. This absorption method has the advantage of a permanentsignal, and the adapted cytoplasmic staining of the sperm plasmamembrane allows the visualization of the outline of the singlespermatozoon. Using this approach, therefore, it is possibleto discriminate between disomic, diploid and abnormal spermatozoa,somatic cells and spermatozoa that overlap, because the morphologyof the cells is not distorted and the tails of the spermatozoaare intact and properly visualized.  相似文献   
35.
目的 :观察大鼠缺氧叠加静注FeCl3 致肺动脉高压模型肺动脉内皮细胞的病理变化。方法 :常规病理组织学和透射电子显微镜及多功能显微镜观察肺动脉内皮细胞的变化。结果 :缺氧叠加静注FeCl3 2周、4周时肺动脉平滑肌肥厚 ,肺间质有大量炎细胞浸润 ,血小板聚集 ,微血栓形成 ,血管内皮剥脱 ,内膜下组织暴露 ,内膜下及弹力纤维变形 ,内皮细胞成片脱落为循环内皮细胞。结论 :缺氧叠加静注FeCl3 引起的肺动脉内皮细胞脱落 ,内膜下组织暴露 ,微血栓形成和平滑肌肥厚是肺动脉高压形成的病理学基础  相似文献   
36.
少弱精子症与精浆附性腺标志物的相关性分析   总被引:1,自引:0,他引:1  
目的分析少弱精子症患者精液参数与精浆附性腺标志物的相关性,探讨附性腺功能对男性生育力的影响。方法采用精液常规、精子形态、精浆附性腺标志物分析方法,检测正常供精者和门诊就诊的少弱精子症患者的精液相关指标。结果少弱精子症组正常形态精子百分数、精子穿透功能、精浆中性α-糖苷酶显著低于正常对照组。相关分析结果显示,少弱精子症患者组,精液量与精子活动率呈负相关(r=-0.415,P<0.05),精子数与形态呈正相关(r=0.393,P<0.05)。结论少弱精子症患者同时存在不同程度的附睾功能障碍,精子功能下降,精子畸形率显著升高,睾丸生精功能越低下,精子畸形发生率越高。  相似文献   
37.
用橡胶木粉填充线性低密度聚乙烯(LLDPE),研究了酸、碱溶液预处理木粉的效果和硅烷偶联荆(KH-570)、MMA接枝的天然橡胶胶乳(MGL-30)两种改性剂对橡胶木粉表面改性的效果,以及未粉粒径和填充量等对木粉/LLDPE复合材料力学性能的影响,并用SEM对复合材料拉伸断面的形态结构进行了分析。结果表明:木粉的拉径、木粉填充量和改性荆用量对复合材料的力学性能有较大的影响,经碱溶液预处理再用改性荆改性后的木粉能有效地改善木粉与LLDPE的界面粘结强度,提高橡胶木粉/LLDPE复合材料的力学性能。  相似文献   
38.
作者前已报道蕲蛇及其伪品滑鼠蛇的鉴别,又据报道有些省发现蕲蛇商品药材中混有烙铁头、山烙铁头两种蛇的干燥体。作者对这两种混淆品与蕲蛇在体表花纹、鳞片以及骨骼的形态与组织特征等方面进行了鉴别研究。  相似文献   
39.
6 cases of different lymphoproliferative diseases were studied with the new MAC (Morphology-Antibody-Chromosome) method in order to find out 1) if the abnormal karyotype is confined to the monoclonal cell population, 2) if there are, within this clone, also cells with a normal karyotype, and 3) if the method can help the pathologist to diagnose malignant lymphoproliferative diseases. The MAC method allows a simultaneous study in the same metaphase cell of the karyotype, surface markers, and some morphological features. In all cases in which a monoclonal cell proliferation was detected immunohistologically, the MAC examination showed a chromosomal abnormality for the same light chain as was detected in immunohistology, but not in other cells. In all but a single case, all mitotic cells belonging to the clonal cell proliferation had an abnormal karyotype. In this case with lambda clonality, 2/8 lambda-positive mitoses had a normal karyotype. However, all the normal mitoses occurred in small lymphocytes whereas the abnormal mitoses were seen in large blastic cells. In 1 case, the MAC method helped in confirming the diagnosis of malignant lymphoma (nodular small cleaved cell type). Especially in lymphomas composed of a mixed cell population, the MAC method makes it possible to find out which cell types have an abnormal karyotype and which have a normal karyotype.  相似文献   
40.
Branching patterns of dendrites may be modulated by the way in which dendritic growth cone filopodia come into initial synaptic relationships with afferent axons. This synaptotropic hypothesis of dendritic branching predicts that dendritic growth will be directed preferentially into regions containing numerous prospective presynaptic elements. The developing mouse spinal cord provides a natural experiment to test this prediction, because synapses are found exclusively within the marginal zones bordering the motor columns during the early (E11-14) period of synaptogenesis. During this time, therefore, most motor dendritic growth would be expected to be directed laterally or ventrally into the marginal zones, whereas internally directed growth should become more prevalent later, when synaptogenesis begins to take place within the intermediate zone, i.e., the motor columns proper. A computer-assisted three dimensional reconstruction system has been used to test these expectations in Golgi preparations of developing mouse (C57BL/6J) spinal cords ranging in age from E13 through P1. Mean dendritic lengths and branch densities are significantly greater for marginal zone dendrites than for intermediate zone dendrites at early ages (E13-14), but there are no significant differences in these measures at later stages of development (P0,1). These findings are interpreted as meaning that motor dendritic growth is initially biased into the marginal zone by synaptogenic afferents and that this preferential distribution is progressively lost as synapses develop within the intermediate zone to attract or to stabilize internally directed dendritic growth. Thus the findings of this study are consistent with predictions of the synaptotropic hypothesis of dendritic branching.  相似文献   
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