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The effects of glucagon on the ultrastructural appearance and acid glucosidase activities in the liver and heart of newborn rats were studied. Liver or heart glycogen-hydrolyzing activity of acid glucosidase increased 3 hours after birth and gradually decreased from 3 to 9 hours. Maltose-hydrolyzing activity of acid glucosidase also rose 3 hours after birth, maintained a plateau between 3 and 6 hours, and fell at 9 hours. The administration of glucagon increased autophagic activity in the hepatocytes at the age of 6 hours. Glycogen inside the autophagic vacuoles was decreased, apparently due to the increased glycogen degradation. Glycogen-hydrolyzing activity was elevated in both the liver and the heart. Maltose-hydrolyzing activity was elevated in the liver, but not in the heart. The results of this study suggest that the glycogen-hydrolyzing and maltose-hydrolyzing activities of acid glucosidase are due to different enzymes. Glucagon's effect on the glycogen-hydrolyzing acid glucosidase activity and autophagosomal morphology is similar in both the liver and the heart.  相似文献   

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Volume growth and proliferation are key processes in heart morphogenesis, yet their regionalization during development of the heart has been described only anecdotally. To study the contribution of cardiomyocyte proliferation to heart development, a quantitative reconstruction method was designed, allowing the local mapping of this morphogenetic process. First, a morphological surface reconstruction is made of the heart, using sections stained specifically for cardiomyocytes. Then, by a comprehensive series of image processing steps, local three-dimensional (3D) information of proliferation is obtained. These local quantitative data are then mapped onto the morphological surface reconstruction, resulting in a reconstruction that not only provides morphological information (qualitative), but also displays local information on proliferation rate (quantitative). The resulting 3D quantitative reconstructions revealed novel observations regarding the morphogenesis of the heart.  相似文献   

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脊柱手术并发脊髓不完全损伤10例临床分析   总被引:1,自引:1,他引:0  
目的:对脊柱手术并发脊髓不完全损伤患者资料进行回顾,分析其临床治疗和预后。方法:以本院脊柱手术后并发不完全损伤10例患者为研究对象,患者手术后均有脊髓不完全损伤的临床表现,给予甲基强的松龙冲击治疗,并加以肢体功能锻炼,术前和术后3个月进行JOA评分和ASIA等级比较。结果:10例患者术前与术后3个月的JOA评分无统计学差异(P>0.05),术后患者ASIA评分低于术前,治疗恢复3个月后脊髓功能的ASIA分级有所改善,恢复至术前或接近术前。结论:脊柱手术并发脊髓不完全损伤程度较轻,经及时的术后治疗和功能锻炼脊髓功能可得到较好恢复。  相似文献   

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We describe the use of a rabbit maxillary sinus model, characterized by thin osseous tissue and low bone density, for the evaluation of surface‐treated implants by histologically and histomorphometrically comparing the osseointegration patterns depending on the surface treatment methods. Twenty rabbits were randomly assigned to two groups of 10 animals, one receiving 5 × 3 mm customized implants (machined, MA or sandblasted and acid etched, SLA) placed in sinus and the other receiving implants placed in a tibia. Histological observation of the implant placed in sinus shows relatively more active new bone formation, characterized by trabecular bone pattern underneath the cortical bone in sinus as compared with that in tibia. Histomorphometric analysis in the rabbits receiving implants in a tibia, the NBIC (%) associated with the SLA surface implant was greater than that associated with the MA implant at 2 weeks (55.63 ± 8.65% vs. 47.87 ± 10.01%; P > 0.05) and at 4 weeks (61.76 ± 9.49% vs. 42.69 ± 10.97%; P < 0.05). Among rabbits receiving implants in a sinus, the NBIC (%) associated with the SLA surface implant was significantly greater than that associated with the MA surface implant both at 2 weeks (37.25 ± 7.27% vs. 20.98 ± 6.42%; P < 0.05) and at 4 weeks (48.82 ± 6.77% vs. 31.51 ± 9.14%; P < 0.05). As a result, we suggest that the maxillary sinus model is an appropriate animal model for assessing surface‐treated implants and may be utilized for the evaluation of surface‐treated implants in poor bone quality environment. Microsc. Res. Tech. 78:697–706, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   

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Adulteration is the root cause of producing not only a chemically and pharmacologically inferior but also in some instances hazardous or poisonous drug. Despite availability of several techniques, microscopy and physicochemical analyses are the most practical approaches for crude drug authentication. Hence, the present study aimed to evaluate morphological, microscopic, and physicochemical properties of root, bark, leaf, and fruit of Diospyros montana Morphological properties were determined by sensory organs, whereas microscopic features of cross‐sections and powders were determined by light and scanning electron microscopy. The proximate and fluorescence analyses were performed using the standard guidelines. The physical examination of fresh, shade‐dried, and powdered material showed no significant change in color. The identifying cellular structures included cuboidal cork, pitted tracheids, scalariform, reticulate and spiral xylary vessels, and rosettes, raphide, and cuboidal calcium oxalate crystals. The stomatal number, stomatal index, vein‐islet and vein‐termination number, and palisade ratio in the leaf were found to be 293.91 ± 32.68 mm?2, 64.18 ± 3.42%, 22.00 ± 3.81 mm?2 and 38.40 ± 5.81 mm?2, and 3.85 ± 0.60, respectively. Total ash, acid insoluble ash, water soluble ash and sulfated ash of leaf (9.00 ± 0.50%, 1.67 ± 0.23%, 2.00 ± 0.22% and 14.50 ± 0.99%, respectively), foaming index of bark and root (111.11 ± 2.11), and swelling index of fruit (19.00 ± 3.45) were higher than the other parts. The powder of different parts showed characteristic colors in the daylight and UV light upon treatment with various regents. The plant was found to be rich in saponins, fibers, and flavonoids. The results of the present study may serve as identifiers of different parts of Diospyros montana.  相似文献   

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In this paper, multiphoton microscopy (MPM), based on two‐photon excited fluorescence and second harmonic generation signals, was used to image microstructures of human rectal mucosa and submucosa. The morphology and distribution of the main components in mucosa layer, goblet cells, intestinal glands, and a little collagen fibers have been clearly monitored, and the content and distribution of collagen, elastic fibers, and blood vessels in submucosa layer have also been distinctly obtained. The variation of these components is very relevant to the pathology in gastrointestinal system, especially early rectal cancer. Our results indicate that the MPM technique has the potential application in vivo in the clinical diagnosis and monitoring of early rectal cancer. SCANNING 32: 347–350, 2010. © 2010 Wiley Periodicals, Inc.  相似文献   

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Spinal cord injury (SCI) is catastrophic and can culminate in disability and death. The routine therapy employed in early stages of SCI currently entails surgical procedures combined with high doses of methylprednisolone (MP). MP is highly controversial for the lack of consensus on its true therapeutic effects. Resveratrol (RES) has recently been recognized as a potential and novel therapeutic drug in SCI. Herein, we investigated the effect of RES in a SCI rat‐model and found significant improvement in Basso–Beattie–Bresnahan scores. Results obtained from histological, immunohistochemistry, and ultra‐structural examinations evidenced the tremendous treatment effect of RES. On the basis of our experimental results, we hypothesize that RES could serve as an effective SCI therapeutic with prolong treatment time following injury.  相似文献   

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Traumatic brain injury (TBI) represents one of the major public health concerns worldwide due to the increase in TBI incidence as a result of injuries from daily life accidents such as sports and motor vehicle transportation as well as military-related practices. This type of central nervous system trauma is known to predispose patients to several neurological disorders such as Parkinson's disease, Alzheimer's disease, chronic trauamatic encephalopathy, and age-related Dementia. Recently, several proteomic and lipidomic platforms have been applied on different TBI studies to investigate TBI-related mechanisms that have broadened our understanding of its distinct neuropathological complications. In this study, we provide an updated comprehensive overview of the current knowledge and novel perspectives of the spatially resolved microproteomics and microlipidomics approaches guided by mass spectrometry imaging used in TBI studies and its applications in the neurotrauma field. In this regard, we will discuss the use of the spatially resolved microproteomics and assess the different microproteomic sampling methods such as laser capture microdissection, parafilm assisted microdissection, and liquid microjunction extraction as accurate and precise techniques in the field of neuroproteomics. Additionally, we will highlight lipid profiling applications and their prospective potentials in characterizing molecular processes involved in the field of TBI. Specifically, we will discuss the phospholipid metabolism acting as a precursor for proinflammatory molecules such as eicosanoids. Finally, we will survey the current state of spatial neuroproteomics and microproteomics applications and present the various studies highlighting their findings in these fields.  相似文献   

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Joel Michell 《Measurement》2005,38(4):285-294
According to the realist interpretation, measurement commits us not just to the logically independent existence of things in space and time, but also to the existence of quantitatively structured properties and relations, and to the existence of real numbers, understood as relations of ratio between specific levels of such attributes. Measurement is defined as the estimation of numerical relations (or ratios) between magnitudes of a quantitative attribute and a unit. The history of scientific measurement, from antiquity to the present may be interpreted as revealing a progressive deepening in the understanding of this position. First, the concept of ratio was broadened to include ratios between incommensurable magnitudes; second, the concept of a quantitative attribute was broadened to include non-extensive quantities; third, quantitative structure and its relations to ratios and real numbers were elaborated; and finally, the issue of empirically distinguishing between quantitative and non-quantitative structures was addressed. This interpretation of measurement understands it in a way that is continuous with scientific investigation in general, i.e., as an attempt to discover independently existing facts.  相似文献   

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Using the transneuronal viral tracing method, the central nervous system (CNS) connections of the uterine horn were studied in virgin, pregnant, and in lactating rats. The frequency of viral labeling in the brain and the distribution of virus-infected neurons from the uterine horn were compared among groups. There was a marked difference in the frequency of viral labeling in the brain stem. In virgin rats more than half of the brain stems (5 out of 9) were labeled. In contrast, in pregnant animals viral-labeled neurons were detected in only a few cases (3 out of 16) and almost each brain stem of the lactating group was labeled (12 out of 13). A similar, less marked difference was observed in the hypothalamus. The pattern of distribution of infected neurons was similar in each group. In the brain stem, the nucleus of the solitary tract, dorsal motor nucleus of the vagus, area postrema, gigantocellular and paragigantocellular nucleus, ventrolateral medulla, A5 cell group, and caudal raphe nuclei were the most frequently labeled structures. In the diencephalon, viral-infected neurons were detected primarily in the hypothalamic paraventricular nucleus. The telencephalon was devoid of infected cells. Data suggest that the CNS control of the uterine horn varies depending on reproductive status. The low frequency of brain labeling in pregnant rats may be related to the almost complete lack of sympathetic fibers in the uterus prior to parturition and the very high frequency of labeling in lactating animals to the postpartum hyperinnervation of the uterus.  相似文献   

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张瑜  陈宇琪  陈磊 《光学仪器》2016,38(2):178-184
研究了一种基于短相干光相移干涉法的便携式光学表面轮廓仪,分析了短相干光干涉显微镜相移干涉技术,实现了基于该项技术的光干涉显微系统。采用光路集成化的设计方法,实现了一体化轮廓仪光路集成,优化了机械三维调整测量台,实现了可用于大、小口径元件表面测量的正置、倒置两种测量模式。测试结果表明,仪器的粗糙度测量精度为0.1nm,重复性误差优于0.01nm,横向分辨率优于1μm。  相似文献   

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Visualizing the interior (lumen) of a tubular structure within tissue can provide a unique perspective on anatomical organization of the tissue. Portal tracts of the liver contain several vessels and ducts in various patterns of intertwining branches and are an example of such spaces. An inexpensive method, using light microscopy and a sample of conventionally stained canine livers, was used to colorize and allow visualization of the lumens of vessels within the portal tract in three dimensions. When the colour of the background was digitally cleared and the lumen filled with a solid colour, it was possible to measure areas and volumes of the portal vein, arteries, bile ducts and lymphatics. Significant differences between vessels and ducts across lobes and gender in control samples are discussed. Differences were also found between control and mixed breed dogs and between controls and a dog that died of accidental traumatic haemorrhage. These differences are discussed in relation to visualizing lumens using images generated from a light microscope. Vessels in plants such as xylem and continuously formed spaces resulting from ice formation are other examples where this technique could be applied.  相似文献   

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Exposure to drugs during pregnancy is a major concern, as some teratogenic compounds can influence normal foetal development. Although the use of drugs during pregnancy should generally be avoided, exposure of the developing foetus to teratogens may occur unknowingly since these compounds may be hidden in products that are being marketed as “all natural.” The aim of the current study was to investigate the possible teratogenic and cellular effects of sibutramine—a serotonin‐norepinephrine reuptake inhibitor used in the treatment of obesity—on the heart and liver tissue of chick embryos. Ephedrine was used as a positive control. The chick embryo model was chosen because it has been used in studying developmental and experimental biology and teratology with great success. The embryos were exposed to three different concentrations of sibutramine and ephedrine respectively. The results obtained revealed that both compounds exhibited embryotoxicity when compared to the control groups. Liver and heart tissue of the exposed embryos was severely affected by these compounds in a dose‐related manner. Morphology similar to that of muscle dystrophy was observed in the heart, where the muscle tissue was infiltrated by adipose and connective tissue. Severe liver steatosis was also noted. A more in‐depth investigation into the molecular pathways involved might provide more information on the exact mechanism of toxicity of these products influencing embryonic development. Microsc. Res. Tech. 78:737–746, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   

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Natural computing for mechanical systems research: A tutorial overview   总被引:1,自引:0,他引:1  
A great many computational algorithms developed over the past half-century have been motivated or suggested by biological systems or processes, the most well-known being the artificial neural networks. These algorithms are commonly grouped together under the terms soft or natural computing. A property shared by most natural computing algorithms is that they allow exploration of, or learning from, data. This property has proved extremely valuable in the solution of many diverse problems in science and engineering. The current paper is intended as a tutorial overview of the basic theory of some of the most common methods of natural computing as they are applied in the context of mechanical systems research. The application of some of the main algorithms is illustrated using case studies. The paper also attempts to give some indication as to which of the algorithms emerging now from the machine learning community are likely to be important for mechanical systems research in the future.  相似文献   

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Increased density of catecholaminergic nerves in the human polycystic ovary has been observed. The aim of the present study was to investigate the distribution of transsynaptically virus-labeled neurons in the central nervous system from the rat polycystic ovary to see whether is it different or not from that of cycling control rats. To induce a polycystic ovary, a single injection of estradiol valerate was given to adult female rats and 30 days later a neurotropic virus was injected into the right ovary. Rats were sacrificed 72 or 96 hours after viral infection. Weight of the ovaries of the estradiol valerate-treated rats was significantly lower compared to controls, and the histology of the ovaries of the treated rats displayed severely atretic large antral follicles. There was almost no viral labeling in the central nervous system from the ovaries showing precystic morphology, in spite of the fact that such altered organs are rich in nerve fibres. It is assumed that presently unidentified factors in the precystic ovary, presumably related to the link between the immune and the nervous system, might be involved in the infectivity of the virus, and thus be responsible for the lack of viral labeling from such an ovary.  相似文献   

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