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51.
Alexander Campbell Alan T Villavicencio Sylva K Yeghiayan Richard Balikian Ross J Baldessarini 《Brain research》1997,771(1):992
Dopamine (DA) at ca. ED50 (16 μg) or saline was stereotaxically microinjected unilaterally 2 h after pretreatment with an MAO inhibitor into left or right nucleus accumbens septi of 697 freely moving rats (1394 injections) to define subregions involved in DA-induced behavioral arousal throughout the anatomical extent of the accumbens. Locomotion was quantified electronically and behavioral responses were assigned to histologically verified injection sites; postural or stereotyped behaviors characteristic of DA injections in caudate-putamen did not occur. Screening with 60 injections across mid-accumbens (2.2–3.2 mm rostral to bregma) indicated that locomotion was elicited non-homogeneously, and was particularly intense dorsomedially. Sites yielding intense arousal and their inactive surround were mapped along the rostrocaudal axis (1.4–4.2 mm anterior to bregma) in coronal sections. Responses to DA showed lateral symmetry and were similar across rostrocaudal levels, with intense responses in dorsomedial accumbens along its border with the caudate-putamen. This functional localization does not coincide closely with reported distributions of DA or its receptors, nor with histologically or histochemically defined core-shell regions of this limbic structure. Nucleus accumbens in rat brain thus appears to be organized functionally into distinct subregions differing markedly in ability to produce locomotor hyperactivity in response to exogenous DA. 相似文献
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53.
Sarah K. Hu Erica L. Herrera Amy R. Smith Maria G. Pachiadaki Virginia P. Edgcomb Sean P. Sylva Eric W. Chan Jeffrey S. Seewald Christopher R. German Julie A. Huber 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(29)
Microbial eukaryotes (or protists) in marine ecosystems are a link between primary producers and all higher trophic levels, and the rate at which heterotrophic protistan grazers consume microbial prey is a key mechanism for carbon transport and recycling in microbial food webs. At deep-sea hydrothermal vents, chemosynthetic bacteria and archaea form the base of a food web that functions in the absence of sunlight, but the role of protistan grazers in these highly productive ecosystems is largely unexplored. Here, we pair grazing experiments with a molecular survey to quantify protistan grazing and to characterize the composition of vent-associated protists in low-temperature diffuse venting fluids from Gorda Ridge in the northeast Pacific Ocean. Results reveal protists exert higher predation pressure at vents compared to the surrounding deep seawater environment and may account for consuming 28 to 62% of the daily stock of prokaryotic biomass within discharging hydrothermal vent fluids. The vent-associated protistan community was more species rich relative to the background deep sea, and patterns in the distribution and co-occurrence of vent microbes provide additional insights into potential predator–prey interactions. Ciliates, followed by dinoflagellates, Syndiniales, rhizaria, and stramenopiles, dominated the vent protistan community and included bacterivorous species, species known to host symbionts, and parasites. Our findings provide an estimate of protistan grazing pressure within hydrothermal vent food webs, highlighting the important role that diverse protistan communities play in deep-sea carbon cycling.Mixing of hydrothermal vent fluids with surrounding seawater in the deep sea creates redox gradients that promote a hub of biological activity supported by chemosynthetic primary production in the absence of sunlight. These localized regions of elevated microbial biomass are important sources of carbon and energy to the surrounding deep-sea ecosystem (1–5). In particular, the consumption of hydrothermal vent microorganisms by single-celled microbial eukaryotes (or protists) is an important link in the food web in which carbon is transferred to higher trophic levels or remineralized to the microbial loop.Protistan grazing is a significant source of mortality for bacterial and archaeal populations in aquatic ecosystems that also influences their composition and diversity (6). Assessments of grazing in the mesopelagic and dark ocean indicate that rates of consumption decrease with depth and correspond to bacterial abundance (7, 8). Therefore, at sites of increased biological activity and microbial biomass, such as areas of redox stratification, protistan grazing is higher relative to the rest of the water column (9, 10). Comparable data are lacking from deep-sea hydrothermal vents, in which the relatively high microbial biomass and rates of primary productivity suggest protistan grazing should be a significant source of microbial mortality and carbon transfer. Furthermore, single-celled microbial eukaryotes can serve as a nutritional resource for other larger protists and higher trophic levels (4, 11).Early microscopic and culture-based experiments from several hydrothermal vents confirmed the presence of single-celled microbial eukaryotes, with observations and enrichment cultures revealing diverse assemblages of ciliates and flagellated protists (12, 13). The study of protistan taxonomy and distribution via genetic analyses at deep-sea vents has uncovered a community largely composed of alveolates, stramenopiles, and rhizaria (14–17). In addition to many of these sequence surveys identifying known bacterivorous species, ciliates isolated from Guaymas Basin were shown to consume an introduced prey analog (18). Collectively, these studies provide supporting evidence of a diverse community of active protistan grazers at deep-sea vents.Here, we investigate protistan predation pressure upon microbial populations in venting fluids along the Gorda Ridge to test the hypothesis that protistan grazing and diversity is elevated within hydrothermal habitats compared to the surrounding deep sea due to increased prey availability. Estimates of mortality via protistan phagotrophy are calculated from grazing experiments conducted with low-temperature, diffusely venting fluid that mixes with seawater at and below the seafloor. Paired 18S ribosomal RNA (rRNA) gene amplicon sequencing from the same experimental sites and incubations reveals the in situ protistan diversity and distribution to evaluate potential preferences in prey, with a focus on the protistan grazer population and their relationship to bacteria and archaea. We present quantitative estimates of protistan grazing from a deep-sea hydrothermal vent ecosystem, thus providing details into the role protists play in food webs and carbon cycling in the deep sea. 相似文献
54.
Background
Acute trauma with laryngeal fracture is a rare injury affecting all functions of the larynx. Resuscitation follows the ABC principles for acute trauma life support. The priority has always been the establishment of an adequate and secure airway. To achieve optimal therapeutic long-term results, permanent stabilisation of the airway and good functional restoration of phonation and swallowing are necessary. We describe the therapy and long-term follow-up of two patients who suffered laryngeal fracture.Case reports
The first case concerns a 31-year-old woman who suffered polytrauma with laryngotracheal separation in a car accident. The fracture was reduced and fixed utilizing miniplates. After decannulation the patient had a patent airway. She regained normal voice and was able to swallow without difficulty. The other case concerns a 16-year-old boy who suffered a laryngeal fracture in a bicycle accident. He also underwent subsequent operative therapy using adaptation plates. This patient also regained an adequate airway and a good postoperative voice. There were no problems with swallowing.Conclusion
Chondrosynthesis with adaptation plates provides an enduring and exact fixation of laryngeal fractures. In the long term, this leads to a stable recovery of function concerning airway, voice, and swallowing. 相似文献55.
Sylva Brtlov Lenka edov Lucie Haviernikov Andrea Hud
kov Frantiek Dolk Petr Sadílek 《Slovenian Journal of Public Health》2022,61(2):101
IntroductionStroke is a disease whose consequences have a considerable impact on the quality of the patient’s life. It is a widespread disease that has a disabling impact on life and, in addition to physical changes, brings about a number of psychological and cognitive processes.GoalThe goal of the study was to identify and describe the quality of life of post-stroke patients.MethodologyThe study design was quantitative. A questionnaire of the authors’ own design and the SF-36 questionnaire were used to obtain the data.ResultsSignificant differences in patient quality of life were identified in relation to patient gender. Moreover, the quality of life in all individual SF-36 dimensions, except for mental health, deteriorated with age. With regard to occupational placement, employed respondents gave the highest evaluation of quality of life according to SF-36 and old-age pensioners the lowest. The analysis shows that quality of life in individual dimensions is positively influenced by respondents’ higher education. The evaluation in individual dimensions improves with the time that has passed since the stroke.ConclusionThe quality of life of post-stroke patients deteriorates with age. The deteriorating level of patient quality of life in older age requires programmes that include assessments and interventions that lead to the treatment of these patients. 相似文献
56.
Štěpán Kutílek Sylva Skálová Jennifer Vethamuthu Pavel Geier Janusz Feber 《Pediatric transplantation》2012,16(1):E5-E9
Kutílek ?, Skálová S, Vethamuthu J, Geier P, Feber J. Transient hyperphosphatasemia in pediatric renal transplant patients – Is there a need for concern and when? Pediatr Transplantation 2012: 16: E5–E9. © 2010 John Wiley & Sons A/S. Abstract: TH of infancy and early childhood is characterized by transiently increased S‐ALP, predominantly its bone or liver isoforms. There are neither signs of metabolic bone disease or hepatopathy corresponding to the increased S‐ALP, nor a common underlying/triggering disease. TH may also occur in children post‐renal Tx, which may raise significant concerns and anxiety. We describe four patients aged 2.8–7 yr in whom the TH occurred at 11–34 (median = 28) months after Tx and lasted from 40 to 105 (median = 63) days. No obvious cause/trigger of TH could be found; the clinical status and bone turnover were not altered. In cases of TH post‐Tx, we recommend the evaluation of basic biochemical indices and wrist X‐ray. If these results are normal, TH is most likely the diagnosis and the S‐ALP can be monitored over the next three months without further testing. In patients with persisting TH for more than three months and/or in children with pre‐existing or suspected metabolic bone disease, further evaluation may be indicated. In conclusion, TH is a benign disorder in patients post‐Tx. Detailed investigation including bone biopsy is only indicated in patients with persisting TH. 相似文献
57.
N P Da Sylva 《Canadian Medical Association journal》1978,119(3):203-204
58.
After introducing the Furlow's double opposing palatoplasty [4] in our clinic in 1991 114 patients were operated on and registered prospectively. Using this procedure for closure of small clefts and/or with moderate velopharyngeal incompetence only at the beginning it became the method of choice not only for primary palatoplasty at the age of 18-24 months but also for corrective measures now. An increase of length of the soft palate of 10 +/- 3 mm at the average was gained immediately after surgery. There were no specific side effects of the method, especially no fistulas occurred. Good speech results were obtained in 61% at the age of 8 years using profound phoniatric tests. Mixed velopharyngeal closure investigated by means of nasal videoscopy was the dominating form in 55%. The results underwent a positive change comparing results in patients after longitudinal investigation at the age of 5 and 8 years bzw. They corresponded with or exceeded the results found in a control group operated on with other methods of palatoplasty at another centre. 相似文献
59.
After introducing the Furlow’s double opposing palatoplasty [4] in our clinic in 1991 114 patients were operated on and registered prospectively. Using this procedure for closure of small clefts and/or with moderate velopharyngeal incompetence only at the beginning it became the method of choice not only for primary palatoplasty at the age of 18–24 months but also for corrective measures now. An increase of length of the soft palate of 10±3 mm at the average was gained immediately after surgery. There were no specific side effects of the method, especially no fistulas occurred. Good speech results were obtained in 61% at the age of 8 years using profound phoniatric tests. Mixed velopharyngeal closure investigated by means of nasal videoscopy was the dominating form in 55%. The results underwent a positive change comparing results in patients after longitudinal investigation at the age of 5 and 8 years bzw. They corresponded with or exceeded the results found in a control group operated on with other methods of palatoplasty at another centre. 相似文献
60.