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1.
Gross and microscopic anatomical investigations were carried out in 14 piglets aged from 4 to 66 days. True Blue (7-50 microliters) and Diamidino Yellow (7-50 microliters) were injected individually into 2 different cardiac sites (the right atrial ganglionated plexus, the inferior vena cava, inferior atrial ganglionated plexus, the right atrium or the right ventricle). Gross anatomy: Globular superior cervical and nodose ganglia, elongated stellate ganglia, multiple small middle cervical ganglia and multiple small mediastinal ganglia along the course of cardiopulmonary nerves were identified. Microscopic anatomy: Neurons innervating specific cardiac regions or intrinsic cardiac ganglionated plexuses were distributed relatively evenly among stellate (primarily in their cranial poles) and middle cervical ganglia bilaterally, fewer labeled neurons being located in the superior cervical and mediastinal ganglia bilaterally. Parasympathetic efferent preganglionic neurons associated with either intrinsic cardiac ganglionated plexus studied were identified primarily throughout the ventrolateral region (the external formation) of the nucleus ambiguus bilaterally. Labeled neurons were also identified throughout the right and left nodose ganglia. Individual neurons did not project axons to different cardiac regions, as no double-labeled neurons were identified. No correlation between age and the numbers and locations of labeled neurons was apparent. Thus, porcine sympathetic efferent neurons which innervate individual cardiac regions, including intrinsic cardiac ganglionated plexuses, lie scattered primarily throughout the right and left mediastinal and middle cervical ganglia as well as the cranial poles of stellate ganglia at birth, apparently changing little during the first 2 months of age. Porcine cardiac parasympathetic efferent preganglionic neurons are located primarily in the external formation of the nucleus ambiguus bilaterally at birth. The numbers of afferent cardiac neurons distributed throughout the nodose ganglia bilaterally also change little during that time. It is concluded that most of the autonomic neurons which innervate the heart are in place at birth.  相似文献   

2.
Female rats were made diabetic with an intravenous injection of streptozotocin (STZ) producing bladder hypertrophy. Using fluorescent dyes injected into the bladder or the colon, we have measured the size of neurons in various ganglia associated with these organs in control and STZ-diabetic rats. These include (1) postganglionic neurons in the pelvic ganglion, (2) postganglionic neurons in the inferior mesenteric ganglion, (3) dorsal root ganglion neurons, (4) sympathetic chain ganglion neurons, (5) preganglionic neurons in the sacral parasympathetic nucleus, (6) motor neurons in Onuf's nucleus innervating the external urethral sphincter. In addition we have measured neurons in some of these groups for rats which have been maintained on a 5% sucrose in water and restricted food diet. In the STZ-diabetic animals only those neurons which make direct contact with the bladder or the colon were found to be hypertrophied (15-70%). In the diuretic animals, only neurons directly innervating the bladder exhibited hypertrophy. We speculate that a trophic factor transported from the organ to the neuron is responsible for this effect.  相似文献   

3.
Trigeminal primary neuronal cell bodies were labeled by retrograde transport of Fluoro-gold (FG) from the nasal mucosa of rats. The trigeminal ganglion containing the labeled cell bodies were processed for double stain for calretinin- and tachykinin-immunoreactivities (CR- and TK-irs). Except for a few contralateral cells, all the cells that innervated the nasal mucosa (NM cells) were confined to the ophthalmo-maxillary division of the trigeminal ganglion ipsilateral to the FG application. In the dorsal two-thirds of the ganglion, NM cells formed a cluster in the rostromedial part of ophthalmo-maxillary division (the rostromedial cluster). In the ventral third, the number of cells in the rostromedial cluster markedly decreased. Instead, numerous NM cells were found in the caudolateral part of the ophthalmo-maxillary division (the caudoventrolateral cluster). CR- and TK-irs were detected in 18% and 54% of overall population of NM cells, respectively. Virtually all of CR-immunoreactive (-ir) NM cells coexpressed TK. Although the proportion of TK-ir cells, irrespective of CR-ir, was similar for both clusters, CR-ir cells were more frequent in the caudoventrolateral cluster than in the rostromedial cluster. In the dorsal 1/3 of the ganglion where all the NM cells belonged to the rostromedial cluster, only 8.4% exhibited CR-ir. On the other hand, as much as 30.1% of NM cells expressed CR-ir in the ventral 1/3 where most NM cells were found in the caudoventrolateral cluster. Trigeminal cell bodies innervating the cornea and conjunctivum were located in the rostromedial part of the ophthalmo-maxillary division.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
Telomeres, the repetitive non-coding DNA sequences found at the ends of all eukaryotic chromosomes, shorten with each cell division. It has been proposed that telomere shortening may be the counting element of a mitotic clock that keeps track of cell divisions; with shortening to a critical length acting as a senescence signal underlying cellular aging. The enzyme telomerase functions to maintain telomere length, thus allowing unlimited cell division, and has been associated with cellular immortalization and cancer. Stem cells have large, perhaps unlimited, replicative capacities. Since these cells are potentially immortal, we reasoned that they might posses active telomerase. We therefore assayed for telomerase activity in the stem cell enriched pools of the androgen-depleted sex accessory tissues in the castrated male rat. Following castration, the ventral prostate and seminal vesicles of the rat involute, losing approximately 90% of their cells by 21 days. These residual glands persist, and are enriched for stem cells, being capable of fully regenerating these glands if testosterone is re-introduced into the animal. We assayed telomerase activity in extracts from normal, involuted, and regenerating ventral prostate and seminal vesicles. Normal glands were found to be telomerase negative, whereas telomerase activity appeared as these glands involuted following castration. Conversely, telomerase activity disappeared during testosterone-induced regeneration of these residual glands. These results provide strong evidence for the ability of androgen to negatively-regulate telomerase activity in stem cell populations of the rat ventral prostate and seminal vesicles. and represent the first in vivo model system for the modulation of telomerase activity.  相似文献   

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7.
A unique case of left ureteral opening into a seminal vesicle, ipsilateral renal hyperplasia and crossed ectopia of the seminal vesicles is reported. This 24-year-old white man underwent a nephroureterectomy for relief of symptoms of lower urinary tract infection. The embryological development of this abnormality is discussed briefly.  相似文献   

8.
The subperiosteal browlift and midface lift combination is a total mobilization of the composite full-thickness soft tissues from the bony skeleton with superior suspension. The object is to correct midfacial ptosis and the "tired" look of the lateral eyelids. It is done in conjunction with a browlift so that a composite correction of the upper and midface is achieved. When indicated, a modified lower cheeklift and the usual procedures for correcting neck deformities are utilized in combination. We believe the procedure is safe and the results reported are natural and long-lasting. This review of 130 cases also stresses technical aspects and the safety of the procedure.  相似文献   

9.
10.
This paper extends the use of principal-component analysis in spectral quantification to the estimation of frequency and phase shifts in a single resonant peak across a series of spectra. The estimated parameters can be used to correct the spectra accordingly, resulting in more accurate peak-area estimation. Further, the removal of the variations in phase and frequency cause by instrumental and experimental fluctuations makes it possible to determine more accurately the remaining variations, which bear biological significance. The procedure is demonstrated on simulated data, a 3D chemical-shift-imaging dataset acquired from a cylinder of inorganic phosphate (Pi), and a set of 736 31P NMR in vivo spectra taken from a kinetic study of rate muscle energetics. In all cases, the procedure rapidly and automatically identifies the frequency and phase shifts present in the individual spectra. In the kinetic study, the procedure is used twice, first to adjust the phase and frequency of a reference peak (phosphocreatine) and then to determine the individual frequencies of the Pi peak in each of the spectra which further can be used for estimation of pH changes during the experiment.  相似文献   

11.
1. In whole cell patch-clamp studies on cultured rat embryonic spinal cord and medullary neurons bathed in tetrodotoxin, DL-2-amino-5-phosphonovaleric acid, and 6-cyano-7-nitroquinoxaline-2,3-dione, large and long-lasting spontaneous inhibitory postsynaptic currents were occasionally recorded. The amplitudes of these events were 1 order of magnitude larger than those of spontaneous miniature inhibitory postsynaptic currents. Because these large currents had reduced amplitudes in calcium-free saline and in solutions containing glycinergic or GABAergic antagonists, we conclude that they were probably produced by large and prolonged release of glycine and/or 4-amino-n-butyric acid (GABA), which subsequently bind to their postsynaptic receptors. 2. The frequency of spontaneous miniature postsynaptic currents increased dramatically during the long, slow decay phase of these large postsynaptic currents. Considering the requirement for extracellular calcium for the occurrence of these large responses, we hypothesize that this increased frequency reflected an increased intracellular calcium concentration in the presynaptic terminal. 3. Similar evidence for large inhibitory postsynaptic currents and prolonged transmitter release was observed in cell-attached patches, which also exhibited the smaller, spontaneous miniature inhibitory postsynaptic currents, suggesting that these large events are properties of single synaptic terminals. 4. A comparison of the properties of these large inhibitory postsynaptic currents recorded in whole cell mode or cell-attached patches showed no statistically significant differences. The overall mean values, then, are 13.9 +/- 1.6 (SE) ms and 4.5 +/- 0.5 s for the 10-90% rise time and duration, respectively. Furthermore, these large events had amplitudes that were 11-fold larger than the mean amplitude of the miniatures (i.e., mean amplitude ratio of 10.8 +/- 0.5). 5. Periodic large increases in the frequency of spontaneous miniature inhibitory postsynaptic currents occurred in both cell-attached patches and in the whole cell mode, and these increases were only sometimes associated with the large inhibitory postsynaptic currents. The rhythmicity in both recording configurations had similar temporal characteristics, with average interburst intervals of 5 and 12-14 s. Presumably these bursts of spontaneous miniature postsynaptic currents reflected periodic oscillations in the Ca2+ concentration in presynaptic terminals. 6. Both the probability and the frequency of occurrence of large inhibitory postsynaptic currents doubled during the 7-day period of time in culture when experiments were performed, suggesting that these large currents may play a role during development.  相似文献   

12.
Mitochondrial density in neurons of the dorsolateral region of the ventral horn at the L5 spinal cord segment in rats was examined using electron microscopy. The gamma motoneurons had a higher density of mitochondria (25.1 +/- 4.2%, n = 19) in the cytoplasm compared to the alpha motoneurons which had a mitochondrial density of 19.4 +/- 4.5% (n = 38). An inverse relationship between cell body size and mitochondrial density was found for alpha (n = 38) and alpha plus gamma (n = 57), but not for gamma (n = 19), motoneuron populations. The higher densities of mitochondria in the smaller neurons correspond well with their metabolic properties since the smaller neurons have the highest oxidative enzyme activities.  相似文献   

13.
In situ hybridization for regulated endocrine-specific protein-18 messenger RNA showed a distinct and limited pattern of expression in the hypothalamus, midline thalamus, amygdala and hippocampus of the rat. High levels of regulated endocrine-specific protein-18 messenger RNA were found in the magnocellular neurons of the hypothalamic paraventricular, supraoptic and accessory nuclei, in the neurons of the periventricular, medial tuberal, arcuate, lateral and perifornical nuclei, infundibular stalk, and in the ventrolateral division of the ventromedial nucleus and compact division of the dorsomedial nucleus. Lower levels of regulated endocrine-specific protein-18 messenger RNA were found in the parvocellular divisions of the paraventricular nucleus as well as in the bed nucleus of the stria terminalis, median preoptic nucleus, medial preoptic nucleus, medial and lateral preoptic areas, subfornical organ, suprachiasmatic nucleus, anterior hypothalamic area, zona incerta, ventromedial nucleus, dorsomedial nucleus and tuber cinereum. Regulated endocrine-specific protein-18 messenger RNA was also found in thalamic structures including the paraventricular, central medial, intermediodorsal, anterodorsal, rhomboid and reticular nuclei. Signal was also identified in the medial and lateral habenula, in the central, medial, basomedial and anterior cortical nuclei of the amygdala, and in the CA1-CA3 and dentate gyrus of the hippocampus. Dopamine may regulate regulated endocrine-specific protein-18 expression in the CNS because (i) regulated endocrine-specific protein-18 was originally identified in melanotropes based on its regulation by dopaminergic agents and (ii) many of the nuclei that contain regulated endocrine-specific protein-18 also receive dopaminergic input. The localization of regulated endocrine-specific protein-18 in the diencephalon suggests that regulated endocrine-specific protein-18 is involved in regulation of limbic and autonomic function, neuroendocrine control of salt and water balance, reproductive function and feeding behavior.  相似文献   

14.
Eosinophilic fasciitis is a disorder characterised by induration of the skin due to chronic inflammation and fibrosis of the subcutaneous septa and muscular fascia. It is different from sclerodermia. This is a clinical entity that presents as swelling, tenderness and stiffness of the extremities associated with peripheral eosinophilia. We described a patient with this disorder with 18 month of evolution who had a bilateral carpal tunnel syndrome. Her disease appeared after steroid treatment. A review of medical literature demonstrated that similar clinical pictures are originated by different causes. Some authors propose to encompass this group of disorder under the designation of "fasciitis-panniculitis syndrome" instead of "eosinophilic fasciitis" although the well-known eosinophilic fasciitis is clearly recognized and demonstrated.  相似文献   

15.
Feeding behavior in Aplysia shows substantial plasticity. An important site for the generation of this plasticity is the modulation of synaptic transmission between motor neurons and the buccal muscles that generate feeding movements. We have been studying this modulation in the anterior portion of intrinsic buccal muscle 3 (I3a), which is innervated by two excitatory motor neurons and identified serotonergic modulatory neurons, the metacerebral cells (MCCs). We have shown previously that serotonin (5-HT) applied selectively to the muscle potently modulates excitatory junction potentials (EJPs) and contractions. All the effects of 5-HT were persistent, lasting many hours after wash out. We examined whether the release of endogenous 5-HT from the MCC could produce effects similar to the application of 5-HT. Stimulation of the MCCs did produce similar short-term effects to the application of 5-HT. MCC stimulation facilitates EJPs, potentiates contractions, and decreases the latency between the onset of a motor neuron burst and the onset of the evoked contraction. The effects of MCC stimulation reached a maximum at quite low firing frequencies, which were in the range of those previously recorded during feeding behavior. The maximal effects were similar to those produced by superfusion with approximately 0.1 microM 5-HT. Although the effects of MCC stimulation on EJPs were persistent, they were less persistent than the effects of 0.1 microM 5-HT. Mechanisms that may account for differences in the persistence between released and superfused 5-HT are discussed. Thus activity in the MCCs has dramatic short-term effects on the behavioral output of motor neurons, increasing the amplitude and relaxation rate of contractions evoked by both B3 and B38 and shifting the temporal relationship between B38 bursts and evoked contractions.  相似文献   

16.
The descending serotonergic system provides a powerful inhibitory input to the dorsal horn of the spinal cord. Little is known about the chemical identity of the spinal neurons that the serotonergic system innervates, although spinal enkephalinergic neurons are likely candidates. This study investigated the apposition of serotonin-immunoreactive varicosities onto enkephalin- and neurotensin-immunoreactive neurons in the rat lumbosacral spinal cord. Using a double immunofluorescence technique, serotonin-immunoreactive varicosities were observed to abut the soma or proximal dendrites of [Met]enkephalin- and neurotensin-immunoreactive neurons. Nearly 75% of all [Met]enkephalin- and neurotensin-immunoreactive neurons were apposed by serotonin-immunoreactive varicosities in the marginal zone and dorsal gray commissure. In substantia gelatinosa, approximately half of the [Met]enkephalin- and neurotensin-immunoreactive neurons were juxtaposed by serotonin-immunoreactive varicosities. [Met]enkephalin-immunoreactive neurons also were bordered by serotonin-immunoreactive varicosities in the nucleus proprius (65%) and sacral parasympathetic nucleus (75%). The results of this study suggest that the descending serotonergic system mediates nociception via probable contacts with intrinsic enkephalin and neurotensin spinal systems. The mode of action of spinal serotonin on enkephalin and neurotensin neurons may be through "volume" transmission vs synaptic or "wiring" transmission.  相似文献   

17.
Ca2+ channels in distinct subcellular compartments of neurons mediate voltage-dependent Ca2+ influx, which integrates synaptic responses, regulates gene expression, and initiates synaptic transmission. Antibodies that specifically recognize the alpha1 subunits of class A, B, C, D, and E Ca2+ channels have been used to investigate the localization of these voltage-gated ion channels on spinal motor neurons, interneurons, and nerve terminals of the adult rat. Class A P/Q-type Ca2+ channels were present mainly in a punctate pattern in nerve terminals located along the cell bodies and dendrites of motor neurons. Both smooth and punctate staining patterns were observed over the surface of the cell bodies and dendrites with antibodies to class B N-type Ca2+ channels, indicating the presence of these channels in the cell surface membrane and in nerve terminals. Class C and D L-type and class E R-type Ca2+ channels were distributed mainly over the cell soma and proximal dendrites. Class A P/Q-type Ca2+ channels were present predominantly in the presynaptic terminals of motor neurons at the neuromuscular junction. Occasional nerve terminals innervating skeletal muscles from the hindlimb were labeled with antibodies against class B N-type Ca2+ channels. Staining of the dorsal laminae of the rat spinal cord revealed a complementary distribution of class A and class B Ca2+ channels in nerve terminals in the deeper versus the superficial laminae. Many of the nerve terminals immunoreactive for class B N-type Ca2+ channels also contained substance P, an important neuropeptide in pain pathways, suggesting that N-type Ca2+ channels are predominant at synapses that carry nociceptive information into the spinal cord.  相似文献   

18.
We used phalloidin staining and immunocytochemistry at the light and electron microscope level to determine the localization of actin in the cell bodies of rat spinal ganglion neurons. The results show that actin is mostly concentrated along the periphery of the neuronal perikaryon, including the perikaryal projections. This localization places actin in a strategic position to be influenced by incoming signals and to produce mechanical tensions able to shape the perikaryal surface.  相似文献   

19.
We investigated the prevalence of quality of care deficiencies in 4,324 Medicare-reimbursed episodes of care provided by 47 home health agencies. The quality of care protocol consisted of a process-oriented, systematic record review by a trained nurse reviewer. Results suggest that an estimated 14.4% of home health care episodes had quality deficiencies with the potential for or actual adverse effects on the patient. Multivariate analyses revealed that the complexity of patients' needs increased the likelihood and severity of the quality problems. Agency ownership was not related to risk of a quality problem, but regional variation in agency effects was observed. Specific problem areas were identified that suggested several ways that home health care could be improved.  相似文献   

20.
Two uncommon cases of dermatofibrosarcoma protuberans with prominent myxoid changes are presented. The tumors appeared as large multinodular cutaneous plaques that arose at the sites of excision of previous tumors some years earlier. In addition to limited fibrous storiform features, focally observed in deep and peripheral portions of the tumors, a diffuse myxoid pattern could be observed. The latter consisted of homogeneous areas of rare, stellate or spindle-shaped cells, haphazardly scattered in abundant myxoid matrix. Cells of myxoid neoplastic tissue showed mainly a positive immunoreaction for fibrohistocytic markers and the absence either of muscular, neural or human progenitor cell antigens. Mitotic figures were fewer and cell proliferation rates were lower in myxoid as compared to those of typical dermatofibrosarcoma protuberans used as a control. The ultrastructural examination of myxoid areas revealed a prevalent fibroblast-like cell population showing dilated cytoplasmic vesicles, sometimes containing glycosaminoglycans-like substances. The extent of myxoid changes together with the characteristic morphological, ultrastructural and immunohistochemical features confirm that myxoid dermatofibrosarcoma protuberans is a distinct variant of this fibrohistiocytic tumor to be considered in the differential diagnosis among myxoid tumors of the skin.  相似文献   

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