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71.
B-lymphocytes or B-cells form a diverse and flexible repertoire of immune cells that are reactive to almost all potential pathogens by means of the production of antigen-specific immunoglobulins. They can be divided into different populations or subsets, characterised by a distinct combination of properties. These subsets are identified on the base of their differentiation status (precursor B-cells, peripheral B-cells), their localisation in the micro-anatomical compartments of the B-cell follicle (marginal zone B-cells, lymphocytic corona B-cells, follicle centre B-cells), and the developmental lineage to which they belong (B-1 cells, and B-2 or conventional B-cells). The latter classification of B-cells into B-1 cells and B-2 cells is commonly followed by immunologists, mainly in the study of mice models, while pathologists and haematologists tend to use a terminology for B-cells which refers to their localisation in the micro-anatomical compartments of the B-cell follicle and/or differentiation status. In this review, we will discuss the various subsets of B-cells and point to the similarities between the various classification systems in use.  相似文献   
72.
Fifty-four patients with chronic progressive multiple sclerosis received prednisone plus oral low-dose cyclophosphamide and either true plasmapheresis (PP) or "sham" PP weekly for 20 weeks in a double-blind controlled study. Immunosuppressive drug therapy alone (sham PP group, n = 29) was associated with improvement (greater than or equal to one step in Kurtzke Disability Status Scale [DSS]; mean change of 1.5) in 8 and stabilization of MS in 18 patients, with this status sustained in 23 patients at follow-up, 11 months after entry. In contrast, 14 of 26 patients who received "true" PP improved (greater than or equal to one step in DSS; mean change of 2.6), and 11 more were stable, with these changes sustained in 23 of 26 patients at follow-up. These differences, overall, between the PP and sham PP groups were significant at p less than 0.007.  相似文献   
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Critically ill patients in the intensive care unit (ICU) have a high risk of developing malnutrition, and this is associated with poorer clinical outcomes. In clinical practice, nutrition, including enteral nutrition (EN), is often not prioritized. Resulting from this, risks and safety issues for patients and healthcare professionals can emerge. The aim of this literature review, inspired by the Rapid Review Guidebook by Dobbins, 2017, was to identify risks and safety issues for patient safety in the management of EN in critically ill patients in the ICU. Three databases were used to identify studies between 2009 and 2020. We assessed 3495 studies for eligibility and included 62 in our narrative synthesis. Several risks and problems were identified: No use of clinical assessment or screening nutrition assessment, inadequate tube management, missing energy target, missing a nutritionist, bad hygiene and handling, wrong time management and speed, nutritional interruptions, wrong body position, gastrointestinal complication and infections, missing or not using guidelines, understaffing, and lack of education. Raising awareness of these risks is a central aspect in patient safety in ICU. Clinical experts can use a checklist with 12 identified top risks and the recommendations drawn up to carry out their own risk analysis in clinical practice.  相似文献   
75.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Seit 1998 erhebt die Bundeszentrale für gesundheitliche Aufklärung (BZgA) im Rahmen ihrer Repräsentativbefragung...  相似文献   
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Studying the mechanisms of molecular interactions in developing tissues demands sensitive molecular biological in vivo and in vitro techniques. Laser capture microdissection (LCM) allows for the isolation of mRNA in histological sections even from single cells, thus enabling the identification of in vivo gene expression products in closely circumscribed tissue areas. The aims of this study were to assess the optimal fixation, processing, and staining conditions to retrieve RNA from microdissected odontoblasts. Fluorometric assays and RT-PCR analysis of alpha 1(I) collagen, dentin sialophosphoprotein (Dspp), and osteocalcin (OC) confirmed that the total RNA isolated from day 0 and day 3 captured odontoblasts was sufficient in quantity and quality. Our results indicate that individual odontoblasts obtained by LCM are morphologically intact and chemically unaltered, allowing accurate molecular and biochemical analyses.  相似文献   
78.
70 patients suffering from multiple myeloma were observed by authors in the last 15 years and three months. In the meantime fifty-two out of them have died, and 18 patients are under permanent care. 43 IgG, 17 IgA, 6 Bence-Jones, 2 IgD types were diagnosed according to the paraprotein distribution, one patient proved to be nonsecretory, and an other one to osteosclerotic form as well. The median survival time was 27 months in the group of deceased patients. In the group followed-up 50.8 months survival time was observed up to the closing of the study. Several prognostic factors were investigated. According to the classification by Durie and Salmon the survival time was 60 months in the patients with stage I, 33 months in stage II., and 9 months in stage III respectively. The prognosis is much poorer in patients into the "B" category: the survival time was 14 months. Classified in the basis of the type of the myeloma-cell, the cases with well matured cells have had the best prognosis with survival time of 46 months, while the most unfavourable prognosis was observed in patients with blast-cell type, with a median survival time of 10 months. The greatest number of patients suffered from multiple myeloma of IgG paraprotein type, in this group the serum IgA level was found to be significantly decreased in the patients died due to inevitable infections. The survival was injured significantly by the occurrence of concomitant severe diseases, to.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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BACKGROUND: We compare the neuronal and behavioural consequences of abnormal visual experience during early infancy for the optokinetic system of cat and monkey with the neuroopthalmological results in man. MATERIAL AND METHODS: Optokinetic eye movements were recorded with the search coil method and electrooculography. In addition, the response properties of single neurons in the visual cortex and pretectum of anesthetized and paralyzed cats and monkeys were determined in electrophysiological experiments. RESULTS: Our data show that monocular deprivation and strabismus lead to an increase of asymmetry of monocular optokinetic nystagmus and a decrease in gain of slow phase optokinetic eye movements during monocular stimulation as well as to a significant decrease of binocular convergence in the oculomotor system of both cat and monkey. Although these changes are basically similar in both species they are not identical. These differential effects may be explained by structural differences. CONCLUSIONS: Assuming a similar neuronal substrate for the optokinetic system in all primates the monkey represents a more suitable animal model for the human visual system than the cat.  相似文献   
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