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1.
Modern clinical studies have found that Pulsatilla radix contains a variety of active ingredients; however, its medicinal parts and microstructure have been controversial. Based on morphological observation and microscopic identification of different structures, we chose Anhui, Henan, Jilin, and Shanxi Province to study Pulsatilla chinensis (Bunge) Regel populations. We specifically addressed different diameters and anatomical structures of different parts of underground organs. We also found that P. chinensis (Bunge) Regel had a “joint point” structure in its underground organ. Above the “joint point” is the rhizome, below the “joint point” is the root. The main medicinal organ is the rhizome. The protective tissues of the endothelial layer of P. chinensis (Bunge) Regel changed in the process of its development. The protective tissues were replaced by epidermis, cortex, endodermis, and phloem. With the secondary growth, the endothelial cells have been radial division. This study showed that morphology and microscopic identification was an important mean of medicinal material identifications, and it had the characteristics of a convenient, fast, and intuitive method to identify the composition and structural characteristics of P. chinensis (Bunge) Regel medicinal parts.  相似文献   

2.
More recent studies indicate that immune cells which secrete their secretory products or cytokines play an important role in reproductive system. In our study, immune cell populations (CD8+ T lymphocytes, CD68+ macrophages, plasma cells, siderophages, eosinophils) and expression of major histocompatibility complex (MHC) class I and class II were examined in female reproductive tract during follicular (n = 13) and luteal phase (n = 10). Plasma cells and eosinophil granulocytes are present in few numbers in luminal epithelium, but abundant in longitudinal muscle layer of uterus, whereas siderophages are the dominant cell type in stroma. Moreover, MHC‐I and ‐II+ cells are expressed by individual cells in organ layers, while CD8+ T cells and CD68+ macrophages are dominant in epithelium and muscle layer, respectively. In conclusion, we did not found significant changes in immune cells according to follicular and luteal phases, but localization and numbers in each organ have changed according to both organ and layers. These results indicate that these factors may play a crucial role not only to generate an immune response but also to have a role in regulation of physiological functions in female reproductive organs.  相似文献   

3.
Due to its expansion, agriculture has become increasingly dependent on the use of pesticides. However, the indiscriminate use of insecticides has had additional effects on the environment. These products have a broad spectrum of action, and therefore the insecticide affects not only the pests but also non‐target insects such as bees, which are important pollinators of agricultural crops and natural environments. Among the most used pesticides, the neonicotinoids are particularly harmful. One of the neonicotinoids of specific concern is thiamethoxam, which is used on a wide variety of crops and is toxic to bees. Thus, this study aimed to analyze the effects of this insecticide in the midgut and Malpighian tubule cells of Africanized Apis mellifera. Newly emerged workers were exposed until 8 days to a diet containing a sublethal dose of thiamethoxam equal to 1/10 of LC50 (0.0428 ng a.i./l L of diet). The bees were dissected and the organs were processed for transmission electron microscopy. The results showed that thiamethoxam is cytotoxic to midgut and Malpighian tubules. In the midgut, the damage was more evident in bees exposed to the insecticide on the first day. On the eighth day, the cells were ultrastructurally intact suggesting a recovery of this organ. The Malpighian tubules showed pronounced alterations on the eighth day of exposure of bees to the insecticide. This study demonstrates that the continuous exposure to a sublethal dose of thiamethoxam can impair organs that are used during the metabolism of the insecticide. Microsc. Res. Tech. 77:274–281, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

4.
The hepatopancreas of crustaceans species has been recognized as an essential target organ to assess trace elements' effects. Due to its dynamic and capability of detoxifying trace metal, this organ often indicates distinct pathological disturbances. In the present work, we intend to evaluate the bioaccumulation of trace metal in three Orchestia species (Orchestia montagui, Orchestia gammarellus, and Orchestia mediterranea) living in symmetry in the banks of Bizerte lagoon (37°13′8″N 09°55′1″E) after their exposure during 14 days to a mixture of copper and zinc, and to highlight the effect of these metals on their hepatopancreas ultrastructure using transmission electron microscopy. At the end of the experiment, results showed that the mortality and the body mass varied according to the used nominal concentrations. Significant alterations were noted in all the treatment groups. The degree of these alterations depends on the used concentration, and they are represented especially by the cells remoteness and the border lyses, the reduction of the nuclear volume, the increase in the cytoplasm density with the presence of trace metal in the nucleus as well as in the vacuole, the disorganization and the destruction of microvilli, the condensation of the majority of cellular organelles and mitochondria swelling. Through this study, Orchestia genus could be an attractive candidate for the biochemical study of trace metal toxicity in Tunisian wetlands.  相似文献   

5.
6.
The Neotropical catfish, Corydoras paleatus (Callichthyidae) is a facultative air‐breathing teleost that makes use of the caudal portion of the intestine as an accessory air‐breathing organ. This portion is highly modified, being well vascularized with capillaries between epithelial cells, which makes it well suited for gas exchange. Instead, the cranial portion is a digestion and absorption site, as it has a typical intestinal epithelium with columnar cells arranged in a single row, villi and less vascularized tunica mucosa. Therefore, the intestine was studied by light and electron microscopy to assess differences between the cranial, middle and caudal portions. To characterize the potential for cell proliferation of this organ, we used anti‐proliferating cell nuclear antigen antibody and anti‐Na+K+‐ATPase monoclonal antibody to detect the presence of Na+/K+ pump. In C. paleatus it was observed that cell dynamics showed a decreasing gradient of proliferation in cranio‐caudal direction. Also, the intestine of this catfish is an important organ in ionoregulation: the basolateral Na+/K+ pump may have an active role, transporting Na+ out of the cell while helping to maintain the repose potential and to regulate cellular volume. Microsc. Res. Tech. 79:140–148, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

7.
Confocal microscopy is a unique and powerful imaging paradigm which allows optical sectioning through intact tissue. Real-time tandem scanning confocal microscopy has previously been used to generate high-magnification two-dimensional (2-D) images of cells in living organ systems. Inherent problems with movement, however, have prevented the in vivo acquisition of complete 3-D datasets. The development of a new objective lens, used in combination with specialized real-time image acquisition procedures, has allowed sequential serial sections to be obtained in vivo from the rabbit cornea for the first time. These sections can be digitially registered and stacked on the computer to provide a 3-D reconstruction of the corneal cells. This technique should serve as a useful method for studying 3-D structures and analysing 4-D phenomena at the cellular level in living animals. Three-dimensional images of a stromal nerve in normal rabbit cornea and of fibroblasts within a rabbit corneal wound are presented as examples of current capabilities.  相似文献   

8.
In addition to causing myiasis in humans, Megaselia spiracularis Schmitz has also been reported as a forensically important fly. In this study, we presented the morphology of all larval instars and puparium of M. spiracularis using scanning electron microscopy. The first instar larva was composed of 12 segments. Antennae and maxillary palp complex were visible. Two spiracular slits could be seen at the posterior spiracle. The branch of posterior spiracular hairs was approximately equal to the palm‐formed base in length. Second and third larval instars were very similar to first instar, except for the presence of anterior spiracle. The labium of the second instar larva was triangular and ventrally curved, whereas it was a bilobed structure and the tip forked in the first instar. The bubble membrance comprised of ≈40 globules presented at the third instar larvae. Puparia showed a retracted cephalic region and a pair of pupal respiratory horns on the dorsum. A comparison of the morphological features between immature stages of M. spiracularis and M. scalaris, a forensically important fly indoors in Germany, Malaysia, and China, was discussed. Microsc. Res. Tech. 75:1297–1303, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

9.
The histomicroscopy and normal anatomy of the major body organ systems were investigated in the adult killifish, Aphanius hormuzensis using histological examination, X‐ray imaging, double staining, light microscopy and scanning electron microscopy (SEM). Based on the histomicroscopic observations, the kidney, liver and swim bladder in the studied species were comparable to other fish models. The anterior portion of the kidney is bulbous, while the posterior portion is narrow and elongated; the liver has a single lobe and the swim bladder is a single‐chambered organ with no connection to the digestive tract (physoclistous). X‐ray imaging and double staining examination showed 12 abdominal and 15 caudal vertebrae and a single hypural plate in the caudal skeleton. According to light microscopy, the scales were rounded to pentagonal in shape with three types of radii (primary, secondary and tertiary), and the urohyal bone was elongated. SEM microscopy showed a single row of tricuspid teeth on the upper and lower jaw, respectively, each tooth has two lateral cusps that are shorter than the middle one. The number of teeth was 17–18 in the upper jaw and 19–20 in the lower jaw. The saccular otoliths were rounded‐trapezoid in shape with a moderately incised and V‐shaped excisura. The members of killifishes are an important group for biologists because of their evolutionary properties, regeneration capacity and usefulness as biological control and also for the ecotoxicological assessment of environmental pollution. The outcomes of this study may provide a useful basis for future research on the genus Aphanius.  相似文献   

10.
A flexible system for the real-time acquisition of in vivo images has been developed. Images are generated using a tandem scanning confocal microscope interfaced to a low-light-level camera. The video signal from the camera is digitized and stored using a Gould image processing system with a real-time digital disk (RTDD). The RTDD can store up to 3200 512 times 512 pixel images at video rates (30 images s?1). Images can be input directly from the camera during the study, or off-line from a Super VHS video recorder. Once a segment of experimental interest is digitized onto the RTDD, the user can interactively step through the images, average stable sequences, and identify candidates for further processing and analysis. Examples of how this system can be used to study the physiology of various organ systems in vivo are presented.  相似文献   

11.
A progestin receptor (PR) has been detected in the olfactory organ of the trout Salmo trutta fario. The specificity of this receptor was high for 17α,20β‐dihydroxy‐4‐pregnen‐3‐one (17α,20β‐DP), but it also bound 17α‐hydroxy‐progesterone (17α‐OHP) and 21‐hydroxyprogesterone (21‐OHP), even when present at low concentrations (10‐fold in relative binding affinity assay). Progesterone (P) competed effectively at much higher concentrations (1,000‐fold in relative binding affinity assay). Immunohistochemical studies carried out with three different monoclonal antibodies against human progesterone receptor (hPR), chicken progesterone receptor hinge region (cPR), and chicken progesterone receptor A/B domain (PR22), revealed that immunoreactivity was present in the epithelium of the olfactory organ of females and males of the trout Salmo trutta fario only against hPR. Western blotting showed two hPR immunoreactive bands of about 62 and 66 kDa. Finally, a portion of the cDNA of about 300 nucleotides extending over the DNA binding domain and the ligand binding domain was cloned and sequenced, revealing a high degree of sequence homology of the PR in Salmo trutta fario with the PR in other teleosts. Microsc. Res. Tech., 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

12.
The ability of bone repair scaffolds to form bone is traditionally evaluated using cell culture and animal experiments. Mouse calvarial organ culture maintains the natural cell‐to‐cell and cell‐to‐matrix relationships as well as the anatomical order, and this model has been used to study the biological behavior of intramembranous bones. The aim of this study was to evaluate the potential of mouse calvarial organ culture to be used as an in vitro model to study the bone regenerative ability of bone repair polymer scaffolds. Critical size defects (CSD) were created in the parietal bones. Electrospun poly(ε‐caprolactone) scaffolds were placed into one group of defects. The remaining defects served as a control. The bones were cultured for 38 days and analyzed with μCT, phase‐contrast microscopy, dissecting microscopy, scanning electron microscopy, and energy‐dispersive X‐ray analyses. This organ culture technique is easily available and could permit researchers to quickly establish a valuable database of candidate bone repair scaffolds. Microsc. Res. Tech. 77:1037–1043, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

13.
The polyphagous planthopper, Kallitaxila granulata (Stål) (Hemiptera: Fulgoromorpha: Tropiduchidae), has been recently introduced into southeastern China, the Philippine islands, and Hawaii, where it has done significant damage to agricultural and forest ecosystems. The external morphology of the heads of adult male and female K. granulata was examined using scanning electron microscopy. Seven types of sensilla were reported: trichoid sensilla and campaniform sensilla on the antennal pedicel, antennal scape and maxilla; plate organs on the antennal pedicel; coeloconic sensilla in Bourgoin's organ on the expanded flagellar base; ampullaceal sensilla on the antennal pedicel; wavy‐pit sensilla on the antennal pedicel and antennal scape; and coin‐shaped sensilla on each lateral side of the labium. Evans' organ was described as placoid sensilla sunk into shallow cuticular cavities below the antennae. The external morphology, distribution, and abundance of sensilla located on antennae, maxillae, and labium in K. granulata were illustrated, with a brief discussion of their taxonomic, phylogenetic, and putative functional significance. Microsc. Res. Tech., 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

14.
Confusion in the species associated with the name of “Bixie” in Chinese Materia Medica began centuries ago. In recent decades, diverse medicinal plants from the genera Dioscorea and Smilax, and even minor species from the genus Heterosmilax, have been documented under the name Bixie or a very similar name as folk medicines in different areas of China. However, the traditional efficacies and chemical profiles of these herbs are not exactly the same and even vary wildly. Comprehensive authentication of multiple Bixie herbs has not yet been attempted. To differentiate and ensure the correct use of these Bixie‐related herbs, in this study, seven sorts of representative Bixie herbs (Dioscorea collettii, D. zingiberensis, D. nipponica, D. septemloba, Smilax china, S. glabra, and Heterosmilax japonica) were characterized based on the microscopic examination of their powders and cryotomed transverse sections. This is not only the first attempt to distinguish Bixie herbs by a comprehensive microscopic techniques, including common light microscopy, fluorescence microscopy, and polarized light microscopy, but also it is the first research to observe characteristics of transections of crude drugs under polarized lighting for the purpose of authentication. Polarized light has been found to provide a number of unique characteristics. The results indicate that starch granules, stone cells, vascular bundles, and other significant tissue features can be used to authenticate “Bixie” herbs. The method was proven to be quick, handy, specific, and simple. It should be widely applicable to other herbal materials. Microsc. Res. Tech. 77:57–70, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   

15.
Reliable EBSD mapping of 90° domains in a tetragonal ferroelectric perovskite has been achieved for the first time, together with reliable automated orientation determination from TEM‐Kikuchi patterns. This has been used to determine misorientation angles at 90° domain boundaries and thus local c/a ratios. The sources of orientation noise/error and their effects on the misorientation angle data have been thoroughly analyzed and it is found that this gives a cosine distribution of misorientation angles about the mean with a characteristic width related to the width of the orientation noise distribution. In most cases, a good agreement is found between local c/a ratios and global measurements by X‐ray diffraction, but some clear discrepancies have also been found suggesting that real local variations are present, perhaps as a consequence of compositional inhomogeneities.  相似文献   

16.
The morphology of stigma has taxonomic values. To further explore the taxonomy of family Asteraceae, the morphological characteristics of stigma of 28 genera, 32 species, and two varieties in the family were observed using scanning electron microscopy. The results indicated that the stigma morphology of these Asteraceae plants could be divided into 10 types, of which eight are reported for the first time. The morphological characteristics of stigma support the close relationship between genera Aster and Erigeron and among genera Sonchus, Taraxacum, and Youngia. Our results enriched the stigma type diversity data and provided a morphological basis for the study of the phylogenetic evolution of Asteraceae.  相似文献   

17.
Hypoderma spp. larvae were observed subcutaneously in the dorsal and lumbar regions of red deer (Cervus elaphus) hunted in the province of León (northwestern Spain) causing a myiasis. They were removed and initially classified by their size, shape, color, and location under the skin into the three larval stages that parasitize these animals. The morphological characteristics of the first and second-instar are described and from the features of the third-instar the species was identified as Hypoderma actaeon. To accurately identify this species, five isolates of genomic DNA from the third-instar, two from the second-instar and two from first-instar of H. actaeon were analyzed by PCR analysis of the COI region of mt-DNA. The results confirmed that the examined samples exactly matched with H. actaeon. This study has shown the morphological identification of the three larval stages of H. actaeon and, for the first time, the first and second-instar larvae have been molecularly characterized. Finally, identification of only H. actaeon suggests that this species is the only affecting red deer in the Iberian Peninsula.  相似文献   

18.
Quantitative X-ray microanalysis in the analytical electron microscope involves the use of Cliff-Lorimer kAB factors to relate measured X-ray intensities from elements A and B to their composition. This study has generated a wide range of these factors for both K and L X-ray lines. The values of the k factor for each element is ratioed to Fe, rather than to Si as has been common practice to date. The use of kAFe rather than kASi factors reduces the uncertainty in the values due to variations in the efficiency of individual energy dispersive spectrometers, thus making the values more universally applicable. New calculations of the value of kAFe have been made from first principles, encompassing all of the most recent values of the cross-section for X-ray ionization. Comparison of the experimental results with both the calculations and existing k factor data has been made. Close attention has been paid to minimizing the errors in both the experimental and theoretical calculations to reduce the overall error in quantification of X-ray energy dispersive spectra in the analytical electron microscope.  相似文献   

19.

Numerical simulations of the HVAB were carried out by using a Reynolds-averaged Navier-Stokes computational fluid dynamics flow solver. For the computation, mixed meshes of unstructured/Cartesian grids were used. An improved laminar-turbulent crossflow transition model γReθtCF+ was used to predict laminar-turbulent transition phenomena. In addition, to achieve high resolute flow solutions, an improved scheme ESWENO-P was employed when calculating inviscid fluxes. To find the turbulence intensity for the simulations, a parametric study was first conducted with the PSP rotor configuration. The influence of the facility walls of the National Full-Scale Aerodynamics Complex was also investigated. Then, the HVAB rotor performance was predicted under conditions obtained by simulations of the PSP rotor. The HVAB rotor performance of the rotor, including thrust/torque coefficients and figure of merit, were analyzed. In addition, flow characteristics, such as laminar-turbulent locations and tip vortex trajectories, were also investigated.

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20.
The uncertainty in ultrasonic thickness measurements as a function of the depthR m.b of a rough layer on the bottom surface of a tested object based on measurements of the separation between the first and second bottom-reflected pulses (more briefly,h 12-method)1 has been investigated. The simplest model of the rough layer, i.e., a layer with rectangular profiles of juts, has been analyzed. The function Δh 12(R m.b ) has been obtained theoretically and tested in experiments. Theh 12-method of thickness measurement has been compared with theh 1-method for objects with rough surfaces. As in the case of theh 1-method, a critical range ofR m.b has been discovered, where the measurements by ultrasonic thickness gauges are unstable, the amplitudes of the first and second bottom-reflected signals are minimal, the uncertainty Δh 12 has the maximal absolute value, has a jump, and changes its sign. The width of this critical range is less than in the case of the input surface. The theoretical conclusions are supported by experimental data.  相似文献   

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