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1.
The order of radio- and ultrasound diagnosis in the filling defects of the renal calyceal-pelvic systems, resulting from radionegative concrements, "vascular imprints", papillary tumors, and renal tumors affecting the calyceal-pelvic system, should be as follows: excretory urography, ultrasound scanning of the kidneys, retrograde pyelography with a double contrast study (a patient in a vertical posture), and angiography. Reliable diagnostic information obtained at the 1st or 2nd stages of investigation, permits the use of less invasive methods like excretory urography and ultrasound scanning. Retrograde pyelography with a double contrast study is recommended in a suspected pelvic papillary tumor. Angiography is indicated for suspected pathological vascular changes and for a planned operation.  相似文献   

2.
Scanning electron microscopy of microcorrosion casts was used to visualize circulatory pathways in the sinusal spleen of dog. The examination of contracted versus dilated organs and variations of the volume of material injected gave an indication of flow dynamics. Minimal injections of material into contracted spleens produced filling of mainly the fastest routes for flow, whereas injections into dilated spleens primarily filled slower routes. This procedure yielded a more complete, three-dimensional picture of the arterial, intermediate, and venous pathways as a whole, and of the relative amounts of flow through different arterial routes. Evidence of flow from capillary lumina out into ellipsoid sheaths was plentiful in casts from dilated spleens, but rare in casts from contracted organs. The pattern of flow within and out of the marginal sinus has been elucidated: A circumferential filling occurs first, followed by a flow that radiates outward into the marginal zone and red pulp. Venous sinuses filled via two routes in addition to the generally accepted path from the reticular meshwork via fenestrations in sinus walls. First, many venous sinuses extending out from the marginal sinus and surrounding marginal zone originated as open-ended tubes continuous with the reticular spaces of the marginal sinus or marginal zone. Second, direct connections of arterial capillaries with venous sinuses in the red pulp were found. Evidence indicating that some mechanism is controlling the flow via these routes is discussed. The strikingly different arrangement of venous sinuses in the subcapsular region is demonstrated.  相似文献   

3.
The purpose of this study is to describe the anatomy and obtain echographic measurements of normal kidneys in brown lemurs (Eulemur fulvus). The anatomical findings show that brown lemur kidneys are comparable to those of rats except for an elongated papilla. The kidneys of 16 (7 females and 9 males) lemurs were examined with two‐dimensional and power Doppler ultrasonography under general anesthesia. Morphometrically, the left and right kidney surface areas are comparable (3.29 and 3.51 cm2). Kidney area has a significant linear correlation with body weight. Echo‐Doppler findings show that the mean renal arterial blood flow speeds for the left and right kidneys are comparable (0.70 and 0.73 m/s). However, flow speed is higher in the male (0.79 m/s) than in the female (0.60 m/s). The renal arterial diameters are between 1.0 and 1.8 mm. The fact that anesthesia can have hemodynamic effects on renal vasculature should be taken into consideration when assessing these echographic results. Am. J. Primatol. 71:647–653, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

4.
An intraventricular neuronal complex has been identified with scanning and transmission electron microscopy at the base of the lamina terminalis of the mouse. The raspberry-shaped complex protrudes from a thickened bulge on the ependymal surface of the lamina terminalis or adjacent rostral floor of the third ventricle. Neurons and occasional ependymal cells cover the surface of the complex. Its core is made up of neurons, ependymal cells, and neuronal processes, which are usually compactly arranged. The core is continuous, through a breach in the ependymal layers, with the subependymal neuropil of the lamina terminalis. Within the core of the complex are large numbers of axodendritic synapses. Axonal varicosities and synaptic terminals are filled with vesicles and mitochondria. Synaptic endings have one of two populations of vesicles: exclusively clear, small, round or flattened vesicles. In view of the known structural and functional characteristics of the lamina terminalis, it is possible that the neuronal complex may participate in neurohormonal regulatory systems of the hypothalamus and hypophysis or in the network of circumventricular organs mediating angiotensin effects.  相似文献   

5.
Generally spoken cloacae have been but little studied. In Polypterus, a brachiopterygian fish, a cloaca only exists during parts of the embryonal and larval life and it gets replaced by structures consisting of an anus and an urinary sinus. In the beginning of embryonal life the posterior opening of the body seems to be nothing else than the original blastoporus. The wall of this opening acquires evaginations; the anlagen of the excretory ducts come in contact with them, establishing in that way a structure, that merits the name of cloaca. During the elongation of the post-vitellin body, the latter gets shifted from the level of metamere XII to that of metamere XXX. Another migration of the cloaca occurs when the digestive system acquires its development. Finally the cloaca may be found under the 47th and 48th muscular segments (at least in the species Polypterus senegalus senegalus Cuvier). During these stages the excretory ducts have build up an urinary sinus that gets separated from the gut. In adults no communication exists any more between the gut and the urinary sinus; the latter is a very destinct organ that may have an impair or pair aspect according to its being filled up. Because of the establishing of a communication with the genital ducts the sinus becomes an uro-genital sinus in the adult.  相似文献   

6.
Flow and stress patterns in human carotid artery bifurcation models, which differ in the bifurcation angle, are analysed numerically under physiologically relevant flow conditions. The governing Navier-Stokes equations describing pulsatile, three-dimensional flow of an incompressible non-Newtonian fluid are approximated using a pressure correction finite element method, which has been developed recently. The non-Newtonian behaviour of blood is modelled using Casson's relation, based on measured dynamic viscosity. The study concentrates on flow and stress characteristics in the carotid sinus. The results show that the complex flow in the sinus is affected by the angle variation. The magnitude of reversed flow, the extension of the recirculation zone in the outer sinus region and the duration of flow separation during the pulse cycle as well as the resulting wall shear stress are clearly different in the small angle and in the large angle bifurcation. The haemodynamic phenomena, which are important in atherogenesis, are more pronounced in the large angle bifurcation.  相似文献   

7.
P. B. Green  P. Linstead 《Protoplasma》1990,158(1-2):33-38
Summary An indirect procedure for the scanning electron microscopy of living complex shoot structures, e.g., an inflorescence tip, employs the polymerization of a dental impression plastic. Application of the plastic to exposed surfaces during prolonged dissection minimizes desiccation. The resulting complex mould is everted so that recesses representing surface detail can be filled with molten epoxy polymer. The mould is then allowed to revert to its original configuration; it is now filled with epoxy. After the epoxy hardens, the resulting cast is sputter-coated and imaged. Intricate structures up to 1 mm in dimension can be imaged with all components, e.g., flowers on an inflorescence, in situ.  相似文献   

8.
The term pseudolymphoma refers to a heterogeneous group of benign reactive T-cell or B-cell lymphoproliferative processes of diverse causes that simulate lymphoma clinically and histologically but usually undergo spontaneous remission. Its pathogenesis is still unclear. The prognosis is good although some evidence suggests that pseudolymphoma may progress to lymphoma. Pseudolymphoma of the urinary tract is extremely rare. We herein report a case of pseudolymphoma of the renal sinus in a 70-year-old man, associated with a high grade urothelial carcinoma of the bladder and to a prostatic adenocarcinoma (Gleason score 6). A brief review of the literature is included. The kidney showed a well-defined, whitish soft mass which involved the renal sinus. Microscopically, the lesion of the renal sinus consisted of a proliferation of small to medium size lymphocytes (CD20 positive and Bcl-2 negative) sometimes arranged in hyperplastic follicular structures. The diagnosis was confirmed by molecular studies which showed an oligopolyclonal IgH rearrangement. To the best of our knowledge, this is the second case of pseudolymphoma with a complete molecular characterization ever described in the renal sinus and the first one associated with multiple urogenital carcinomas.  相似文献   

9.
A computational pre-processing tool for generating initial configurations of molecules for molecular dynamics simulations in geometries described by a mesh of unstructured arbitrary polyhedra is described. The mesh is divided into separate zones and each can be filled with a single crystal lattice of atoms. Each zone is filled by creating an expanding cube of crystal unit cells, initiated from an anchor point for the lattice. Each unit cell places the appropriate atoms for the user-specified crystal structure and orientation. The cube expands until the entire zone is filled with the lattice; zones with concave and disconnected volumes may be filled. When the mesh is spatially decomposed into portions for distributed parallel processing, each portion may be filled independently, meaning that the entire molecular system never needs to fit onto a single processor, allowing very large systems to be created. The computational time required to fill a zone with molecules scales linearly with the number of cells in the zone for a fixed number of molecules, and better than linearly with the number of molecules for a fixed number of mesh cells. Our tool, molConfig, has been implemented in the open source C++ code OpenFOAM.  相似文献   

10.
Analyzing the data available in the literature and examining echographic, urographic, and computed tomographic findings in 153 patients having various types of the doubled pelvicalycus and other structures of the kidney have led to the conclusion that it is more correct to use term "renal parenchymal intersections" rather than that "Bertin's column hypertrophy" since they are a variant of the anatomic structure of the renal parenchyma. The renal parenchymal and pelvicalyceal intersections outline congruence symptom, which was first noted while comparing echo- and urographic data and studying computed tomographic contrast-enhanced images, may be helpful in the differential diagnosis of the intersections with renal tumors.  相似文献   

11.
Appropriate nephron function is dependent on the intrarenal arrangement of blood vessels. The preferred and primary means to study the architecture of intrarenal circulation has been by filling it with opaque substances such as india ink, radio-opaque contrast material, or various polymers for study by light or scanning electron microscopy. With such methodologies, superficial vessels may obscure deep vessels and little quantitative information may be obtained. Serial-section microtomy has not been practical because of problems relating to alignment and registration of adjacent sections, lost sections, and preparation time and effort. Microcomputed tomography (micro-CT) overcomes such limitations and provides a means to study the three-dimensional architecture of filled vessels within an intact rodent kidney and to obtain more quantitative information. As an example of micro-CT's capabilities, we review the use of micro-CT to study the alterations in renal microvasculature caused by the development of liver cirrhosis after chronic bile duct ligation. In this example, micro-CT evidence shows a selective decrease in cortical vascular filling in the kidney, with a maintenance of medullary vascular filling. These changes may contribute to the salt and water retention that accompanies cirrhosis. These results indicate that micro-CT is a promising method to evaluate renal vascular architecture in the intact rodent kidney relative to physiological and pathological function.  相似文献   

12.
肾素(原)受体在大鼠肾小球系膜细胞和肾脏的表达   总被引:1,自引:0,他引:1  
He M  Huang YL  Zhang L  Yao T  Lu LM 《生理学报》2007,59(6):796-804
近年发现的肾素(原)受体(renin/prorenin receptor,RnR)已被证明具有生物学功能,在心、肾及多种细胞表达。本文旨在观察RnR在体外培养的大鼠肾小球系膜细胞(mesangial cells,MCs)和肾脏中是否表达,及其表达的细胞部位,并用RnR的多肽阻断剂肾素原“柄区肽”(handle region peptide,HRP)与RnR结合后观察受体复合物进入细胞的过程与定位。结果显示,RnR主要存在于大鼠肾脏皮质肾小球系膜区和体外培养的MCs的细胞核周围胞浆和细胞膜。将FITC标记的HRP(FITC-HRP)加入细胞培养液后30S到30min期间,可观察到FITC-HRP由培养液转移到胞浆内并进入细胞核。用免疫荧光和激光共聚焦技术观察到,HRP与RnR的共定位主要位于细胞膜和细胞核周围胞浆;在30min时,一部分HRP已进入细胞核,而RnR没有进入细胞核内,仍主要位于细胞核周围胞浆。上述结果提示,RnR与其配基结合后进入细胞内并发挥生物学效应。  相似文献   

13.
The Murex saxatilis L. (Mollusca, Prosobranchia) osphradium is of the most complex "ctenidial" type and is situated immediately behind the siphon that brings water to the mantel cavity. By means of scanning and transmissive electron microscopical investigation, three zones have been revealed on the surface of the osphradium petals: secretory, intermediate and receptory. The secretory zone occupies the lateral part of the petal and is formed with 1-2 layers of cells. The intermediate zone, as a narrow stria, is situated between the secretory and the receptory zones. Here, together with the secretory cells, the ciliary cells are present. The receptory zone occupies nearly the whole surface of the petal. It is much thicker and is formed of pseudostratified epithelium where 5-7 raws of nuclei can be counted. Besides the cell types mentioned, there are defined bipolar receptory cells in it. The apical surface of the receptory cells has up to 200 cilia, and fine peripheral processes--1-2 cilia. Presence of the complex receptory zone makes it possible to suggest certain differentiation of the stimuli already at the peripheral level of the sensory system.  相似文献   

14.
The gills of the African freshwater crab Potamon niloticus -Ortmann have been investigated by scanning and transmission electron microscopy. Potamon has seven pairs of phyllobranchiate gills contained in the branchial chambers. From the central axis of the gills arise bilaterally situated thin flaps, the lamellae. The afferent branchial vessel (the epibranchial vessel) is located on the dorsal aspect of the gill arch and the efferent vessel (the hypobrancial vessel) on the ventral side. Between these two blood vessels, the blood percolates through the lamellar vascular channels where it is oxygenated. The lamellae consist of an epithelial cell layer covered by a thin cuticle which consists of tightly fused but distinct layers. The epithelial cells approach each other at regular intervals and fuse in the middle of the lamellar sinus delineating the vascular channels. Apical profuse membranous infoldings and numerous mitochondria characterize the epithelial cells, features typical of cells involved in active transport of macro- and micromolecules. In Potamon , however, there were no distinct gas exchange and osmoregulatory regions of the gills. On average, the cuticle was 0.78 μm thick while the epithelial cell was 6 μm. Cells that were morphologically similar to the renal glomerular podocytes of the vertebrates were observed in the efferent gill vessel of Potamon. These cells have been said to be phagocytic and may play an important defensive role in the crustaceans. Although basically the morphology of the gills of Potamon is similar to that of the other decapods, fine structural differences were evident as would be intuitively expected in a group of animals that has undergone such remarkable adaptive radiation.  相似文献   

15.
《Journal of morphology》2017,278(8):1020-1032
Most nonmammalian synapsids possess a mid‐dorsal depression in the brain cavity known as the “unossified zone.” It remains obscure which structures this zone contained, and, as candidates, the vermis of the cerebellum, the superior sagittal sinus, a junction of several blood vessels, the pineal gland or other midbrain structures were considered. Neutron tomography of a skull of Diictodon feliceps (Therapsida, Anomodontia) revealed some clear impressions of canals in this region of the brain cavity. Furthermore, the prootic sinus probably ran on the internal surface of the pila antotica and had a similar course in anomodonts as it has been proposed for cynodonts and Mesozoic mammals. Comparisons with the vascular systems of nonmammalian synapsids and mammals suggest that the unossified zone is best interpreted as a terminal chamber of the anterior segment of the medial head vein, which housed the junction of the superior sagittal sinus and the transverse sinuses. Consequently, the system of cranial vessels in Diictodon reveals a partial division of the medial head vein system into an anterior and a posterior segment at an early stage of synapsid evolution, which is consistent with the well‐known common pattern of early ontogenetic development in amniotes. J. Morphol., 2017. © 2017 Wiley Periodicals, Inc.  相似文献   

16.
Avian heads are characterized as having two extensive air-filled systems lined with epithelia; the paranasal and paratympanic sinuses. Many diverticula derived from the paratympanic sinus system are known to reticulate with each other to form a single merged pneumatic space within the adult braincase. However, the development of these complex branching and reticulating epithelia has not been examined in detail. In this study, we describe the comprehensive developmental pattern of the paratympanic sinus and its associated soft tissues in a model bird, Japanese quail (Coturnix japonica). The data are derived from three-dimensional reconstructions based on histological sections and soft tissue enhanced micro-CT data. Those data provide the foundation of the complex hierarchical developmental pattern of the paratympanic sinus system. Moreover, associations with other tissues help establish key morphologies that identify each pneumatic entity. This study clarifies the developmental relationships of the ventral portions of the paratympanic sinus system, the siphoneal diverticulum and marginal sinus, based on the ligaments associated with the Eustachian tube. In addition, detailed histological pneumatic morphologies reveal hitherto unknown epithelial diversity, which may be indicative of equally complex developmental processes. We use the pneumatization of the quadrate as an example to support a close relationship with vascular growth and pneumatic epithelia invasion into ossified bone. We confirm pneumatic diverticula never enter into cartilages, possibly due to the absence of vasculature in these tissues. Lastly, we use the concept of a morphogenetic tree as a tool to help present the complex developmental pattern of the paratympanic sinus system and apply it toward inferring pneumatic morphologies in a nonavian theropod braincase.  相似文献   

17.
Summary A casting technique has been employed to display in three dimensions, the lymphatic microcirculation within the human lymph node. The casting compound filled the marginal sinus, and diffusely permeated the cortical lymphoid parenchyma. However, deep within the lymph node in the medullary region, the medium remained within the limits of the sinus walls. The casts showed well-defined channels appearing similar to vessels. These converged into larger vessels, which drained into efferent lymphatics leaving the node at the hilus.Electron microscopic examination showed that the outer wall of the marginal sinus and the trabecular side of trabecular sinuses had an intact, continuous endothelium with a basement membrane. However, gaps were present in the inner wall of the marginal sinus, as well as in the parenchymal wall of the trabecular sinus. In the medulla, the sinuses were lined by endothelial cells which appeared similar to macrophages. The sinus lining was incomplete and possessed numerous perforations. These observations indicated that sinus walls adjacent to connective tissue served as a barrier to cell movement, but those adjacent to a large lymphoid cell population had gaps, with cells in apparent transit between sinus lumen and parenchyma.  相似文献   

18.
The nucleolar protein fibrillarin has been studied in onion cells; it is detected as an Mr 37,000 protein by immunoblotting using a human autoimmune serum. Quantitative immunoelectron microscopy showed that most fibrillarin is localized in the transition zone between the fibrillar center (FC) and the dense fibrillar component (DFC) as well as in the priximal zone of the DFC, where the labeling shows a gradual decrease out-ward until it reaches insignificant levels in the distal zone of the DFC. Thus, fibrillarin is not uniformly distributed throughout the DFC of plant cells. This result supports the hypothesis that the morphologically homogeneous DFC may not be uniform in function; it is also in agreement with the hypothesized vectorial flow of ribosome biogenesis through the same compartments. Data are also presented showing that the amount of fibrillarin increase when nucleolar activity increases in G2, and probably decreases when nucleolar activity decreases during differentiation.  相似文献   

19.
Summary The authors have studied the activity of alkaline and acid phosphatase in the rat and the mouse vaginal anlage. The activity is high in the epithelium of the müllerian vagina and low or uncertain in that of the sinus vagina. When a lumen is formed in the latter, there appears in rat an activity of both phosphatases of the same intensity as seen in the müllerian vagina. In mouse, the epithelium of the müllerian vagina transitory loses its activity of alkaline phosphatase when the epithelium undergoes transformation. The whole vagina is then surrounded by a zone of high stromal activity of alkaline phosphatase. The epithelium lacks activity except in the fornix region where the activity remains in a zone close to the lumen Thereafter the activity disappears in the subepithelial strorna and instead apears in the basal layer of the epithelium. The activity of acid phosphatase increases in the mouse sinus vagina at the same time as lumen is formed, being of the same intensity here as in the müllerian vaginal part.  相似文献   

20.
The ultrastructure of neurons of the diffuse supraoptic nucleus of the hamster has been studied. These neurons show two specializations of the endoplasmic reticulum: annulate lamellae and whorl bodies. From one to three whorl bodies are found in the same neuron. The annulate lamellae and the whorl body cisterns are continuous with the cisterns of the rough endoplasmic reticulum. These neurons present an extraordinarily developed rough endoplasmic reticulum, small mitochondria, neurosecretory vesicles and a Golgi complex filled with electron-dense material. Astrocytic processes of different thickness surround the neurosecretory cells.  相似文献   

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