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151.
As a non-invasive method, ultrasound is a suitable diagnostic procedure for routine in vivo examination of the human skin in dermatology. In this study 40 healthy test subjects were examined with a 20-MHz ultrasound scanner in order to determine the thickness and morphology of normal skin at 51 different sites. B-mode ultrasonography permits us to measure both the individual layers of the skin and deeper structures and to assess their definition and echogenicity. In both sexes the greatest skin thicknesses were found on: the shoulder-blade (mean thicknesses (mm), males 3.07/ females 2.47); the upper back (m, 3.04/f, 2.85); the chin (m, 3.04/f, 2.69); the lower lip (m, 2.66/f,2.50) and in the region of the lower back (m, 2.64/f, 2.39). Particularly thin skin was found on: the upper eyelid (m, 0.59/f, 0.64); the lower eyelid (m, 0.99/f, 0.86); in the groin (m. 0.97/f, 0.90); in the armpit (m, 1.01/f, 1.09) and on the forearm (m, 1.13/f. 1.00 mm). Knowledge of differences in the characteristic reflex patterns depending on the sex and age of the subject and the site of the skin examined forms the basis for assessment of pathological sonograms.  相似文献   
152.
The effect of thyrotropin-releasing hormone (TRH), a neuropeptide physiologically present in the mammalian hippocampus, on spontaneous, miniature and evoked GABAergic postsynaptic currents was investigated using whole-cell patch-clamp recording from pyramidal cells and interneurons of the rat hippocampal thin slice preparation. Bath application of 10 μM TRH induced an increase in the frequency of spontaneous postsynaptic currents from 1.07 ± 0.68 to 3.16 ± 0.73 Hz in pyramidal neurons and interneurons of the stratum lacunosum-moleculare (SL-M). In tetrodotoxin solution TRH did not change miniature postsynaptic currents. Application of TRH to minislices containing only the CA1 region still produced an increase in the spontaneous postsynaptic current frequency, indicative of an action by TRH upon a local GABAergic circuitry. Paired recordings from one pyramidal cell and one stratum lacunosum moleculare interneuron displayed synchronous events whose frequency rose after TRH application, suggestive of a common, TRH-sensitive input. In a small subset of cells TRH induced the appearance of highly rhythmic large postsynaptic currents at a frequency of ∼2 Hz, as confirmed by autocorrelation analysis. Postsynaptic currents electrically evoked by focal stimulation of stratum lacunosum-moleculare were depressed from 90 ± 27 to 44 ± 15 pA after application of TRH. This phenomenon was solely due to an increase in the number of synaptic failures. It is proposed that the effect of TRH on the GABAergic system was primarily exerted on a subset of interneurons controlling the activity of pyramidal cells as well as stratum lacunosum-moleculare interneurons.  相似文献   
153.
154.
Abstract We measured the concentrations of total porphyrins and their metabolites (uro-, hepta-, hexa-, penta-, copro- and protoporphyrin) in various human tissues: liver, erythrocytes, skin, adipose tissue, and mammary gland. The porphyrin concentrations varied within minor limits, e.g., 3.1 ±2.3 nmol porphyrins/g liver and 0.50±0.10 nmol/g erythrocytes. No significant differences were detectable in other tissues in comparison with liver. In all tissues, the predominant metabolite was protoporphyrin, followed by coproporphyrin, whereas only low concentrations of higher carboxylatcd porphyrins such as uroporphyrin were detectable. It is concluded that porphyrin metabolism and its regulation is similar in all human tissues, perhaps with some small differences in the erythrocytes.  相似文献   
155.
Corneal xenotransplantation may be an alternative approach to overcome shortage of allografts for clinical transplantation. Orthotopic corneal rat-to-mouse xenotransplantation and syngeneic transplantation was performed and the effects of anti-CD4 and anti-CD8 treatments on corneal xenograft survival and production of cytokines, interleukin (IL)-2, IL-4, IL-10, gamma-interferon (IFN-gamma) and nitric oxide (NO) were evaluated. RT-PCR was used to determine the expression of genes for cytokines and inducible nitric oxide synthase (iNOS) in the grafts. The presence of iNOS protein in grafts was detected by immunofluorescent staining. We found that corneal xenotransplantation was associated with a strong upregulation of genes for both Th1 and Th2 cytokines and with NO production in the graft. Treatment of xenograft recipients with mAb anti-CD4, but not anti-CD8, resulted in a profound inhibition of IL-2, IL-4 and IL-10 production, and in a significant prolongation of corneal xenograft survival. The results show that upregulation of Th2 cytokines after corneal xenotransplantation does not correlate with xenograft rejection. Rather, corneal graft rejection is associated with the expression of genes for IFN-gamma and iNOS and with NO production.  相似文献   
156.
Noncompliance with therapy is one possible explanation for the observation that long-term graft survival is not sufficiently improved by the development in immunosuppression. The aim of the study was to explore the prevalence, characteristics and risk factors of noncompliance with immunosuppression. A total of 161 adult kidney transplant recipients were interviewed about their self-rated health, social support, education, stress from adverse effects and compliance with the immunosuppression. The prevalence of subclinical noncompliance was 54%. Noncompliant patients declared significantly worse self-rated health, less satisfaction with social support and higher stress from adverse effects. Male gender (OR 7.5, CI 2.4-23.39), high stress from adverse effects (OR 12.27, CI 2.44-61.88), fair self-rated health (OR 4.45, CI 1.04-19.55) and fair satisfaction with social support (OR 4.55, CI 1.08-19.24) were predictors of noncompliance. Standardized detection methods should be developed with the aim of identifying patients who are at risk of noncompliance in order to prevent graft loss.  相似文献   
157.
Abstract: For almost 15 years microencapsulated islets have been successfully transplanted in different animal models. Besides long-lasting success, a certain rate of graft failures also has been reported. This study evaluated the cellular immune response toward alginate-polylysine microencapsulated islets (mc-islets) in vitro by means of mixed-lymphocyte-islet-culture. Method: Islets were isolated from LEWIS-rats and lymphocytes from the spleens of NMRl-mice. After overnight culture and prior to encapsulation the islets were gamma-irradiated with 22.5 Gy. 50 mc-islets, 50 nonencapsulated islets, and 50 empty me were co-cultured for 72 h with 1 × 106 in 1 ml medium in 24-well plates. Thymidine incorporation during the last 24 hr served as a measure for lymphoid activation. Result: Non-encapsulated islets were potent stimulators of lymphoid proliferation. This could be reduced by 55% when the islets were entrapped in microcapsules. Empty microcapsules induced a minor lymphoid activation (18% of mc-islets) only. Conclusion: Despite encapsulation islets could be recognised by lymphocytes in vitro. This may explain at least partially graft failure rates after transplantation of encapsulated islets.  相似文献   
158.
159.
Isolated distal fibula fractures represent the majority of ankle fractures. These fractures are often the result of a low-energy trauma with external rotation and supination mechanism. Diagnosis is based on clinical signs and radiographic exam. Stress X-rays have a role in detecting associated mortise instability. Management depends on fracture type, displacement and associated ankle instability. For simple, minimally displaced fractures without ankle instability, conservative treatment leads to excellent results. Conservative treatment must also be considered in overaged unhealthy patients, even in unstable fractures. Surgical treatment is indicated when fracture or ankle instability are present, with several techniques described. Outcome is excellent in most cases. Complications regarding wound healing are frequent, especially with plate fixation, whereas other complications are uncommon.  相似文献   
160.
Correction to “Freire de Melo F, Martins Oliveira Diniz L, Nélio Januário J, Fernando Gonçalves Ferreira J, Dórea RSDM, de Brito BB, Marques HS, Lemos FFB, Silva Luz M, Rocha Pinheiro SL, de Magalhães Queiroz DM. Performance of a serological IgM and IgG qualitative test for COVID-19 diagnosis: An experimental study in Brazil. World J Exp Med 2022; 12(5): 100-103 [PMID: 36196438 DOI: 10.5493/wjem.v12.i5.100]”. In this article, we identified an issue with the “Acknowledgments” section. Here, we then provide a recognition section for our supporting institutions.  相似文献   
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