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1.
Differences in the Raman spectrum of the α‐ and β‐polymorph of poly(propylene) (PP) have been identified in the form of band shifts distinct for the specific polymorph. A new method has been developed, which can ascertain the presence of the α‐polymorph. These band shifts have been used to profile both the polymorphs and variations in the crystallinity across the whole spherulite have been ascertained by carrying out a spatially resolved profiling of the degree of crystallinity. The crystalline domains in PP have been qualitatively assessed using the band shifts in the Raman spectra. This approach has then been applied to study local variations in the morphology of welds between PP plates, wherein the complex interplay between the heating and cooling patterns as well as the mechanical forces due to shearing gives rise to the development of a different morphological structure in the weld. Using Raman microscopy, a reduction in the crystallinity (≈18%) in the region of the weld seams and sporadic formation of β‐spherulites in the weld core is observed. The methodology developed has been applied to investigate a weld between PP‐H and PP‐R (PP with random ethylene copolymer), to ascertain the variations occurring upon welding in such materials.

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2.
目的 探究足踝体外生物力学实验中肌力对足关节接触力、峰值压强以及接触面积的影响,为选择合适的加载方式提供依据。 方法 踝关节中立位状态下,对新鲜小腿和足离体标本分别进行有无肌力两种方式加载,测量加载状态下第 1 跖趾关节、第 2 跖趾关节、第 1 跖楔关节、第 2 跖楔关节、内侧楔舟关节、中间楔舟关节、距舟关节、 跟骰关节、距下关节(后关节面)以及胫距关节的接触力、峰值压强和接触面积,并对结果进行对比分析。 结果 与无肌力加载状态相比,进行肌力加载时足第 1 跖趾关节、第 2 跖趾关节、第 1 跖楔关节、第 2 跖楔关节、内侧楔舟关节、中间楔舟关节、距舟关节和胫距关节的关节接触力均显著增大( P < 0. 05),变化百分比分别为 719. 28%、311. 37%、128. 67%、50. 82%、54. 89%、57. 63%、79. 98% 和 50. 34% ;足第 1 跖趾关节、第 1 跖楔关节和距舟关节的关节峰值压强显著增大(P<0. 05),变化百分比分别为 176. 14%、62. 91% 和 40. 07% ;足第 1 跖趾关节、第 1 跖楔关节、中间楔舟关节以及距下关节(后关节面) 的关节接触面积均显著增大( P < 0. 05),变化百分比分别为 132. 20%、55. 41%、30. 97% 和 26. 87% 。 结论 足踝标本生物力学实验中,进行肌力加载对足各关节的关节接触力、峰值压强或接触面积均产生显著影响,前足表现尤甚。 在进行相关体外标本研究时,需要考虑肌力加载对足踝受力情况的影响,为足踝生物力学实验提供参考。  相似文献   

3.
The microphase separation and morphology of PDEG‐b‐PCH‐b‐PDEG and PCH‐b‐PDEG‐b‐PCH amphiphilic triblock copolymers have been studied by DSC, SAXS and AFM. A clear first‐order scattering peak was observed for most of the triblock copolymers, independent of the macroinitiator used. This diffraction has been ascribed to the development of a lamellar structure, which was confirmed by AFM. On the other hand, the existence of an ODT upon heating was observed for most of the triblock copolymers. The ODT location was dependent on the outer segment molecular weights, shifting at higher temperatures as the polymerisation degree increased. WAXS profiles were checked to determine the glass transition and ODT temperatures.

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4.
The Iberian lynx is the most endangered felid species. During winter/spring 2006/7, a feline leukemia virus (FeLV) outbreak of unexpected virulence killed about 2/3 of the infected Iberian lynxes. All FeLV-positive animals were co-infected with feline hemoplasmas. To further characterize the Iberian lynx FeLV strain and evaluate its potential virulence, the FeLV envelope gene variable region A (VRA) mutant spectrum was analyzed using the Roche 454 sequencing technology, and an in vivo transmission study of lynx blood to specified-pathogen-free cats was performed. VRA mutations indicated weak apolipoprotein B mRNA editing enzyme and catalytic polypeptide-like cytidine deaminase (APOBEC) restriction of FeLV replication, and variants characteristic of aggressive FeLV strains, such as FeLV-C or FeLV-A/61C, were not detected. Cats exposed to FeLV/Candidatus Mycoplasma haemominutum-positive lynx blood did not show a particularly severe outcome of infection. The results underscore the special susceptibility of Iberian lynxes to infectious diseases.  相似文献   

5.
In this study, Rana ridibunda was used as samples because of their wide use in Turkey. Male frogs were collected in the East Marmara region each month throughout 1 year. Frogs from every monthly collection were used to analyze structural components of the thumb pads and testes. Spermatogenetic activity of Rana ridibunda living in the East Marmara region was determined to be “potentially continuous” type. Generally, the increase in the number and the size of nuclei of Leydig cells was inversely proportional to the fluctuation of spermatogenetic activity. The lumen of the seminiferous tubules in testes contained, in addition to the spermatogenic cells, a Periodic‐acid Schiff‐positive granular material. The amount of this material varied throughout the year, and that finding suggested a function related to spermiation. The components of thumb pads exhibited structural changes with respect to the activities of Leydig cells. During the periods where the Leydig cells were active, mucus glands (also called breeding glands) of thumb pads were also developed. On the other hand, we observed mixed glands with unknown function, which as first reported by us, and were poison glands in the thumb pads. The results suggest structural changes in the thumb pads are linked to changes in the testes. Anat Rec, 291:1106‐1114, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   

6.
The molecular and histological structure of the fat bodies covering externally the posterolateral region of the jaw of the striped dolphin (Stenella coeruleoalba) was investigated by means of morphological and nuclear magnetic resonance techniques. The analyses of samples belonging to adult and juvenile individuals were performed with the aim of seeking the presence of age‐related differences. In our study, the level of isovalerate (iso5:0) in the extramandibular fat of the juvenile individuals is comparable with those of the adult counterparts; conversely, longer isobranched fatty acids were detected in lower quantities in the juveniles together with a higher degree of unsaturation. The morphologic analyses revealed that, in both adults and juveniles, this fatty tissue is similar to univacuolar adipose tissue. However, in the juveniles, a muscular component was present, whereas only in adult subjects, enlarged and irregularly shaped cavities may be seen within the adipose tissue. These cavities, structurally organized as veins, may regulate blood flow in response to changing water temperature and stabilize thermal gradient within the jaw lipids. These data suggest that the molecular components and the histological organization can indicate a maturation of the organ with age that probably may reflect different sound reception properties. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   

7.
Summary Lipoprotein(a), as an atherogenic particle, represents an independent risk factor for coronary heart disease. In the present study the morphological distribution of apoprotein (a) and apoprotein B within the arterial wall is described. Apoprotein B, a constituent of very low-density lipoprotein, low-density lipoprotein and lipoprotein(a) has previously been demonstrated in atheromatous lesions. Lipoprotein(a) possesses an additional protein, designated apoprotein (a). Autopsy material (n=74) from the left coronary artery and from the thoracic aorta has been examined by means of immunohistochemistry and both apoprotein (a) and apoprotein B were detected, primarily associated with the extracellular matrix and accumulating in lesions in the arterial wall. The staining pattern for both antigens was almost always found to be congruent, suggesting that the detection of (a)-antigen has to be attributed at least in part to the presence of lipoprotein(a). It is concluded that both low-density lipoprotein and lipoprotein(a) have an important role in the pathogenesis of atherosclerosis.  相似文献   

8.
The Clouded leopard (Neofelis nebulosa) is a medium‐sized highly arboreal cat. This study compares the structure of the digital, metacarpal and metatarsal pads of the manus and pes in N. nebulosa to that of the domestic cat (Felis catus). Covered by a stratified squamous cornified epithelium, the pads have a supple deposit of subepidermal fat that is partitioned by collagen fibers and extensively anchored to the muscle tendon sheaths. In both animals, a pes metatarsal pad suspensory ligament originates from the Mm. flexores digitorum profundi tendon and forms 3–4 small branches that project through the dermal fat layer and attach to the pad epidermis. In the cat manus, four tendons of equal size extend from the M. flexor digitorum superficialis (FDS) to form the manica flexoria in digits 2–4 from which extends a metacarpal pad suspensory ligament (MPSL) on digits 2 and 5 that extends into the tela subcutanea and epidermis. On digits 3 and 4 MPSL extends directly from the FDS tendon itself. In contrast, manus FDS tendons 1 and 5 in N. nebulosa were thin and either project directly to the tela subcutanea (tendon 1) or connect with the manica flexoria forming a metacarpal pad suspensory ligament (tendon 5). Tendons 2–4 connect with the manica flexoria from which MPSL project into the tela subcutanea and epidermis. In both species, the suspensory ligaments may serve to contract the pad to conform to the under lying substrate, thus enhancing the animal's ability to grip branches while climbing. Anat Rec, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

9.
Red‐tailed phascogale (Phascogale calura) pouch young at birth were relatively underdeveloped in comparison with their eutherian counterparts, and the lymphoid tissues of the immune system were found to be histologically immature. The phascogale thymus rapidly developed in the first few days of pouch life and was quickly populated with lymphocytes. By the end of pouch life, involution of the thymus was underway. The bone marrow started to develop in the early stage of pouch life, although adipocytes and megakaryocytes were not observed until slightly later. The liver was hematopoietic from birth and reached histological maturity toward the end of pouch life. The lymph nodes were difficult to detect macroscopically because of their small size, but were easily identified microscopically later in pouch life, particularly in the mesentery, and these lymph nodes exhibited germinal centers by the end of pouch life. The early spleen was predominately mesenchymal, but exhibited some erythropoiesis. Follicles with well‐developed germinal centers were not observed until the latest stage of pouch life. Although intraepithelial lymphocytes were detected in the intestines early in pouch life, the discrete lymphoid aggregates and Peyer's patches characteristic of the gut‐associated lymphoid tissue (GALT) were not detected until later in pouch life. This is the first report of histological development in phascogale pouch young, as well as the first report of the thymus, bone marrow, and lymph nodes in this dasyurid species at any age. Anat Rec, 299:207–219, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   

10.
目的 为肩峰撞击征的诊断和治疗提供断层解剖学基础。 方法 (1)取15例女性标本进行肩关节的断层切割观察;(2)运用MRI技术对10例女性健康人的肩峰下脂肪垫进行测量。 结果 (1)肩峰下脂肪垫上方为斜方肌,下方为冈上肌,在肩峰下面与肩峰下三角肌滑膜囊相邻,在横断面上呈方形,在斜矢状断面和斜冠状断面上呈长条形;肩峰下脂肪垫长度为(48.91±7.5)mm, 宽度为(28.0±4.7)mm,肩峰下脂肪垫厚度在冈上肌中部为(11.5±1.9)mm,在肩峰外缘为(3.1±0.8)mm。(2)MRI轴位、斜矢状位、斜冠状位可清楚显示肩峰下脂肪垫,肩峰下脂肪垫长度(49.8±7.0)mm, 宽度为(28.7±5.2)mm,肩峰下脂肪垫厚度在冈上肌中部为(12.5±1.5)mm,在肩峰外缘为(3.2±0.8)mm。(3)断层肩峰下脂肪垫长度、宽度、厚度观测值数据和MRI数据分别进行t检验结果无差异(P>0.05)。 结论 MRI的肩峰下脂肪垫测量可以为肩峰撞击症早期诊断提供解剖学依据。  相似文献   

11.
The avian pineal is a directly photosensory organ taking part in the organization of the circadian and seasonal rhythms. It plays an important role in regulation of many behavior and physiological phenomena including migration. The aim of the study was to investigate morphology of the pineal organ in the common gull (Larus canus). The light and electron microscopic studies were performed on the pineals of juvenile birds living in natural conditions of the Baltic Sea coast, which have been untreatably injured during strong storms in autumn and qualified for euthanasia. The investigated pineals consisted of a wide, triangular, superficially localized distal part and a narrow, elongated proximal part, attached via the choroid plexus to the intercommissural region of the diencephalon. The accessory pineal tissue was localized caudally to the choroid plexus. Based on the histological criteria, the organ was classified as the solid‐follicular type. Two types of cells of fotoreceptory line were distinguished: rudimentary–receptor pinealocytes and secretory pinealocytes. Both types of cells were characterized by unusual features, which have been not previously described in avian pinealocytes: the presence of paracrystalline structures in the basal processes and their endings, the storage of glycogen in the form of large accumulations and the arrangement of mitochondria in clusters. Further studies on other species of wild water birds dwelling in condition of cold seas are necessary to explain if the described features of pinealocytes are specific for genus Larus, family Laridae or a larger group of water birds living in similar environmental conditions. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

12.
13.
This study aimed to describe the morphology, expression of IgA and IgG in adult yak tonsils. The 12 clinically healthy yak tonsils [3- to 6-year old, n = 12] were examined for morphology using light, and transmission electron microscopes. Expression of IgA and IgG was measured by qRT-PCR, ELISA, and immunohistochemistry. The results showed that the palatine tonsil, the tonsil of the soft palate, and the lingual tonsil were oropharyngeal tonsils. The stratified squamous epithelia covering them had a thick underlying layer of connective tissue and their crypts were heavily infiltrated by lymphocytes. The pharyngeal tonsil and the tubal tonsil were nasopharyngeal tonsils. The epithelia of them was predominantly pseudostratified columnar ciliary epithelium, which were loosely arranged with a number of desmosomes or intermediate junctions variably connecting them. The expression levels of IgA and IgG mRNA and protein from high to low was in the pharyngeal tonsil, palatine tonsil, tonsil of the soft palate, lingual tonsil, and tubal tonsil, respectively. Interestingly, the expression of IgG was very significantly higher than that of IgA in yak tonsils (P < 0.01). Both the IgA and IgG ASCs were distributed in the subepithelial areas of the non-reticular crypt epithelium, especially areas of pseudostratified columnar ciliary epithelium, the reticular crypt epithelium, lymphoid follicles, interfollicular areas, and with some of the positive cells aggregating around the glands. The results indicated that the tonsils were not only typical secondary lymphoid organs but also lymphoepithelial structures. IgG could be a significant component of mucosal immune responses in yak tonsils. Anat Rec, 302:999–1009, 2019. © 2018 Wiley Periodicals, Inc.  相似文献   

14.
The mammaries from carcasses of two female Amazonian manatees were examined. Trichechus inunguis possesses two axillary mammaries beneath the pectoral fins, one on each side of the body. Each papilla mammae has a small hole on its apex—the ostium papillare. The mammaries are covered by a stratified squamous keratinized epithelium. The epithelium of the mammary ducts became thinner more deeply in the tissue and varied from stratified to simple cuboidal. There was no evidence of glandular activity or secretion into the ducts of the mammary glands. Anat Rec, 297:1532–1535, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

15.
Spherical microspheres composed of polymer blends 80: 20 PEAD/PCL II and 40:40: 20 PEAD/P(HB-HV)/PCL II containing a range of BSA loadings have been fabricated using a single emulsion technique with solvent evaporation. 80: 20 PEAD/PCL II microspheres had smooth surfaces while 40:40:20 PEAD/P(HB-HV)/PCL II microspheres consisted of a mixture of smooth surfaced, microporous and macroporous microsphere fractions. Irrespective of fabrication polymer, microspheres were produced in high yield (> 75%) and BSA incorporation had no significant effect on microsphere size distribution which ranged from 0.6 to 5 μm and from 2.1 to 50 μm for 80: 20 PEAD/PCL II and 40:40: 20 PEAD/P(HB-HV)/PCL II microspheres, respectively. The loss of BSA by partitioning into the aqueous phase resulted in low encapsulation efficiencies (< 14.5%). BSA release increased significantly with theoretical percentage loading but the relationship could not be confirmed when the total cumulative release of BSA was expressed as a percentage of the actual total BSA incorporated. Significant BSA release could be detected for up to 26 days.  相似文献   

16.
血清EMAb和CA125水平对子宫内膜异位症诊断价值的探讨   总被引:2,自引:4,他引:2  
目的:探讨了血清抗子宫内膜抗体(EMAb)和血清CA125水平对子宫内膜异位症(EMS)的诊断价值。方法:应用ELISA法和放免法分别测定了54例子宫内膜异位症患者血清EMAb和CA125水平,并和35例正常健康人作比较。结果:子宫内膜异位症患者EMAb阳性检出率显著高于正常人组(P<0.01),CA125水平也明显高于正常人组(P<0.01)。结论:测定子宫内膜异位症患者血清EMAb和CA125水平对子宫内膜异位症有一定的诊断价值,联合测定EMAb和CA125水平更有实用价值。  相似文献   

17.
The seminal ducts (efferent ductule, epididymis, and deferent duct) in adults of Phrynops geoffroanus were examined using light microscopy. A series of tubules (efferent ductules) connect the testes to the epididymides. The efferent ductules are formed by a rete of small tubules of varying diameters, with simple columnar epithelium formed by the ciliated cells, nonciliated cells, and few basal cells. The epididymis is a simple, long and highly convoluted tubule that receives the efferent ductules throughout its extension. It is covered by a pseudostratified columnar epithelium with three cellular types: the principal cells, which are the most abundant, basal cells, and a small narrow cell. The histological differences in the epididymis region (cranial, medial, and caudal), as well as the differences in the epithelium throughout the reproductive cycle, are discussed. The deferent ducts consist of a low pseudostratified epithelium with two cellular types: the principal and basal cells. During the months analyzed, spermatozoa were stored in the epididymis, and deferent ducts were found. Anat Rec, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

18.
The sinus node of yak has been studied by the histological methods and transmission electron microscopy. The sinus node artery of yak was also determined by the injection‐corrosion casting technique, the angiography, and histological methods. The results showed that the sinus node of yak contained an extensive framework of collagen and two main type cells: pacemaker cells (P cells) and transitional cells (T cells). The P cells had a perinuclear clear zone, contained less myofibrils, and appeared smaller mitochondria than T cells. The T cells were longer and slender than P cells, and had a variety of shapes. At the periphery of sinus node there were many nerve fibers and ganglions. Gap junction did not reveal reaction with anti‐connexin43, but it was detected by electron microscopy in the central part of sinus node of yak. The sinus node artery of yak originated from left coronary artery more frequently (98%) than by right (2%). The artery located at the periphery of sinus node. It had an internal elastic membrane throughout its course, and a large nerve bundle was found running in a longitudinal direction. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

19.
Dinosaurs possess a form of tooth attachment wherein an unmineralized periodontal ligament suspends each tooth within a socket, similar to the condition in mammals and crocodylians. However, little information is known about tooth attachment and implantation in their close relatives, the silesaurids. We conducted a histological survey of several silesaurid taxa to determine the nature of tooth attachment in this phylogenetically and paleoecologically important group of archosaurs. Our histological data demonstrate that these early dinosauriforms do not exhibit the crocodilian/dinosaur condition of a permanent gomphosis, nor the rapid ankylosis that is plesiomorphic for amniotes. Instead, all sampled silesaurids exhibit delayed ankylosis, a condition in which teeth pass through a prolonged stage where the teeth are suspended in sockets by a periodontal ligament, followed by eventual mineralization and fusion of the tooth to the jaws. This suggests that tooth attachment in crocodylians and dinosaurs represent the further retention of an early ontogenetic stage compared to silesaurids, a paedomorphic trend that is mirrored in the evolution of synapsid tooth attachment. It also suggests that the dinosaur and crocodylian gomphosis was convergently acquired via heterochrony or, less likely, that the silesaurid condition represents a reversal to a plesiomorphic state. Moreover, if Silesauridae is nested within Ornithischia, a permanent gomphosis could be convergent between the two main dinosaur lineages, Ornithischia and Saurischia. These results demonstrate that dental characters in early archosaur phylogenies must be chosen and defined carefully, taking into account the relative duration of the different phases of dental ontogeny.  相似文献   

20.
Dyggve-Melchior-Clausen syndrome without mental retardation (Smith-McCort dysplasia) (SM) has clinical and radiographic findings similar to those of Dyggve-Melchior-Clausen syndrome (DMC) except for mental retardation. Iliac crest biopsies from two patients with SM were examined. The lace-like appearance of the iliac crests, which is a characteristic radiological sign of SM and DMC, was caused by bone tissue deposited in a wavy pattern at the osteochondral junction. The growth plate showed abnormal enchondral ossification with no columnarization of chondrocytes. Electron microscopy demonstrated chondrocytes with dilated cisternae of rough endoplasmic reticulum containing fine granular or amorphous material, similar to those reported in cases of DMC. Thus, SM has pathologic changes in common with DMC as a rough endoplasmic reticulum storage disorder, even though the mental condition is different. Am. J. Med. Genet. 72:11–17, 1997. © 1997 Wiley-Liss Inc.  相似文献   

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