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21.
Horii A Smith PF Darlington CL 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,140(2):252-200
Spontaneous recovery from the oculomotor and postural symptoms of unilateral labyrinthectomy (UL) is known as vestibular
compensation, which is a useful model for investigation of the mechanisms of lesion-induced CNS plasticity. In the present
study, to elucidate the molecular biological basis of vestibular compensation, we investigated changes in the mRNA expression
of glutamate receptor subunit/subtypes in the rat central vestibular system, including the vestibular nucleus complex (VNC),
inferior olive (IO), and cerebellar flocculus following UL, using a real-time quantitative polymerase chain reaction (PCR)
method. In normal control animals, regional differences in the expression of several glutamate receptor subunit/subtypes,
e.g., NR1 and NR2A subunits of the N-methyl-D-aspartic acid (NMDA) receptor, GluR2 and KA2 subtypes of non-NMDA receptors, and mGluR1 and mGluR7 metabotropic glutamate
receptors, were consistent with previous results from studies using in situ hybridization histochemistry, suggesting that
the real-time quantitative PCR method was a reliable procedure for evaluation of changes in mRNA expression. In the vestibular
nucleus complex, NR2A, GluR2 and mGluR7 mRNA were ipsilaterally downregulated by 6 h following UL (P<0.05, P<0.05 and P<0.01, respectively). In the inferior olive, no changes in gene expression were observed. In the ipsilateral flocculus, KA2
mRNA expression was increased by 50 h post-UL (P<0.05). However, in the contralateral flocculus, mGluR1 mRNA was downregulated by 6 h post-UL (P<0.005). Both the increase in KA2 mRNA expression in the ipsilateral flocculus and the decrease in mGluR1 mRNA expression
in the contralateral flocculus may have had the effect of reducing Purkinje cell inhibition of ipsilateral VNC neurons, thereby
contributing to the rebalancing of spontaneous resting activity between the ipsilateral and contralateral VNCs. It is suggested
that such changes in the activities of the floccular-VNC pathways may be important to the vestibular compensation process.
Electronic Publication 相似文献
22.
V. P. Dobrynin V. A. Fedan I. Yu. Orbachevskaya E. N. Pogozheva E. S. Neprintseva 《Bulletin of experimental biology and medicine》1989,108(2):1068-1071
Research Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR Research Laboratory of Biologically Active Substances of Hydrobionts, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR G. N. Kryzhanovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 108, No. 8, pp. 139–142, August, 1989. 相似文献
23.
AIM: Digital imaging is useful in conventional photography because it immediately provides images, and the image quality can be improved afterwards by the use of computer programs. The major disadvantages of consumer-type digital cameras mounted on microscopes are (i) unequal illumination through the image, and (ii) a coloured background. A computer program was specifically adapted and refined to improve images obtained with consumer-type digital cameras mounted on microscopes. METHODS AND RESULTS: An approach using a division operation between the specimen image and a background image leads to homogeneous illumination throughout the image, with automatically corrected brightness and white background. The correct colour spectrum is preserved by correction of the histogram. This approach was obtained from the freeware computer program 'Image Arithmetic'. In a test, three different consumer-type digital cameras (Sony, Nikon, Olympus) on different microscopes were used to obtain images of different types of histological specimens (cervical smear, bone marrow biopsy, and colonic biopsy). The computer program dramatically improved the quality of images obtained with all tested cameras. CONCLUSION: Using this approach, even low-cost digital cameras mounted on microscopes produce brilliant images with homogeneous illumination and a white background, the image quality being comparable with expensive cameras especially designed for microscopes. 相似文献
24.
The COVID-19 pandemic is known to influence the dietary habits of adults, but results for adolescents in studies are ambiguous. The present work aimed to analyze the differences in the scores of the Adolescents’ Food Habits Checklist (AFHC) before and during the pandemic in the Polish Adolescents’ COVID-19 Experience (PLACE-19) Study population. The PLACE-19 Study was conducted during the pandemic among a population of 2448 students recruited from secondary schools in all regions of Poland using a random quota sampling. The participants were required to complete an AFHC consisting of 23 items pertaining to food purchase, preparation, and consumption habits. Current habits (during the pandemic) and previous habits were assessed and scored separately. The total (p = 0.001), purchase (p < 0.001), and consumption scores (p = 0.014) indicated that the AFHC scores during the pandemic were higher than before. For questions on purchase habits, a lower number of respondents reported eating in a restaurant, eating takeaway meals, having lunch away from home, or buying pastries, cakes or crisps. For questions on preparation habits, an greater number of respondents reported that they usually avoided eating fried food and tried to keep their overall sugar intake down, but fewer respondents said they tried to have low-fat desserts. For questions on consumption habits, a lower number of respondents reported that they usually ate a dessert or pudding if one were available and a larger number said they made sure to eat at least one serving of vegetables or salad a day and at least three servings of fruit most days. Based on the obtained results, it may be stated that although there was an increase in the AFHC scores during the pandemic, a similar share of respondents showed improved or worsened food habits, and a similar share changed their food habits from healthy to unhealthy and from unhealthy to healthy. At the same time, a majority of changes were associated with purchase habits, which were probably forced by lockdowns and the resultant restrictions in eating out or grocery shopping. 相似文献
25.
26.
William M. Cregar J Brett Goodloe Yining Lu Tad L. Gerlinger 《The Journal of arthroplasty》2021,36(2):488-494
BackgroundPrevious evidence has demonstrated an exacerbating effect of increased operative time on short-term complications in total joint arthroplasty. While the same relationship may be expected for unicompartmental knee arthroplasty (UKA), supporting evidence remains sparse. The purpose of this study is to determine the impact of operative time on short-term complication rates after UKA and determine a critical threshold in operative times after which complications may increase.MethodsThe American College of Surgeons National Surgical Quality Improvement Project was queried from 2007 to 2018 to identify 11,633 UKA procedures that were included in the final analysis. The effect of operative time on complications within 30 days was evaluated using multivariate logistic regression models. Receiver operating characteristics curves and spline regression models were used to identify critical thresholds in operative time that increase the likelihood of short-term complications.ResultsLonger operative times (in minutes) were associated with higher rates of surgical site infection (90.4 ± 26.7 vs 84.8 ± 25.5, P = .003), blood transfusions (94.9 ± 28.6 vs 84.9 ± 25.5, P = .007), as well as reoperation rates (90.8 ± 27.9 vs 84.9 ± 25.5, P = .01), extended hospital length of stay (93.4 ± 29.8 vs 84.5 ± 25.2, P < .001), and mortality (110.4 ± 35.5 vs 84.9 ± 25.5, P = .008). Following multivariate logistic regression, operative time was found to independently predict increased surgical site infection, blood transfusion, myocardial infarction, extended length of stay, and mortality (odds ratio: 1.09 – 1.45, CI: 1.01 – 1.91, all P values <0.02). Receiver operating characteristics curves found an increase in mortality risk during the 30-day postoperative period after 88.5 minutes of operative time, a finding supported by spline regression plots.ConclusionThe present study found a positive correlation between increased operative times and short-term postoperative complication rates after UKA. Despite a statistically significant association with increasing operative time, odds ratios of reported complications are relatively low. 相似文献
27.
C. R. Evans R. Jones G. Phillips G. Greene M. Phillips R. Morris-Clarke 《Anaesthesia》2021,76(5):639-646
Cardiac surgical patients with anaemia experience increased morbidity and mortality. Iron deficiency is the most common cause of pre-operative anaemia in this group. We designed and implemented the Cardiff Pathway, a pre-assessment and treatment pathway to identify cardiac surgical patients with anaemia and iron deficiency. Patients identified with anaemia and/or iron deficiency (Hb < 130 g.l-1 and ferritin < 100 μg.l-1) were offered intravenous iron infusion 20 mg.kg-1 pre-operatively. Treatment success was defined as Hb ≥ 130g.l-1 on the day of surgery. We analysed data from 447 patients: 300 (67%) were not anaemic; 75 (17%) were anaemic and treated with intravenous iron; and 72 (16%) were anaemic and not treated. Haemoglobin concentration increased in successfully treated anaemic patients by a mean (95%CI) of 17 (13–21) g.l-1 and they received a median (IQR [range]) of 0 (0–2 [0–15]) units of blood peri-operatively. Transfusion was avoided in 54% of the successfully treated anaemic patients, which was significantly more than the unsuccessfully treated anaemic (22%, p = 0.005) and untreated anaemic (28%, p = 0.018) patients and similar to non-anaemic patients who received a median (IQR [range] of 0 (0–1 [0–16])) units of blood and, 63% avoided transfusion). Mean (95%CI) Hb fell between pre-assessment and surgery in the untreated anaemic (-2 (0 to -4) g.l-1) and non-anaemic groups (-2 (-1 to -3) g.l-1). Twenty-one (7%) of the non-anaemic group became newly anaemic waiting for surgery. The Cardiff Pathway reliably identified patients with anaemia and iron deficiency. Anaemic patients who had their Hb restored to normal after treatment required less blood peri-operatively and over half of them required no transfusion at all. 相似文献
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30.
目的:探讨国产吻、缝合器在超低位直肠前切除术中的应用。方法:对27例直肠癌患者行超低位直肠前切除,应用上海产金钟牌缝合器、吻合器,进行结肠-直肠吻合。结果:本组根治性切除25例(92.6%);1例发生吻合口瘘,发生率为3.7%;吻合口狭窄3例,发生率为11.1%,均经保守治疗治愈。结论:合理使用国产缝合器、吻合器可完成超低位直肠癌的保肛手术,可达保肛、根治、降低费用、减少并发症的目的。 相似文献