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101.
Disseminated infection with the coelomycetous fungus Nattrassia mangiferae is a very rare disease affecting only the immunocompromised host. We report the first case of a disseminated infection with spondylodiscitis and granular skin lesions due to N. mangiferae in a renal transplant patient.  相似文献   
102.
To maintain the intracellular concentration of ions and small molecules on osmotic challenges, nature has developed highly sophisticated transport systems for regulating water and ion content. An ideal measurement technique for volume changes of cells during osmotic challenges has to fulfil two requirements: it has to be osmotically inert, and it should allow online monitoring of cell volume changes. Here, a simple fluorescence microscopy-based approach is presented. Using fluorescein as a negative stain, it is possible to monitor cell volume changes without affecting the functionality of cell membranes and cell osmolarity. Measurement of Madine-Darby canine kidney (MDCK) cells after hypo- and hyperosmotic challenges reveals the main advantages of this approach: besides providing precise and reproducible quantitative data on reversible cell volume changes, the viability of the cells can be assessed directly by the appearance of stain in the cytoplasm. This becomes evident especially after hypo-osmotic challenge of glutaraldehyde-treated cells, which become leaky after fixation, followed by a massive volume change. This new approach represents a very sensitive measurement technique for cell volume changes resulting from water or ion flux, and thus seems to be an ideal tool for studying cell volume regulatory processes.  相似文献   
103.
The induction of contact sensitivity in mice by hapten reagents such as trinitrochlorobenzene (TNCB) involves the activation of class II major histocompatibility complex (MHC)-restricted, hapten-specific, CD4+ T cells. Reports from different laboratories have indicated that the relevant antigenic epitopes in such reactions might include hapten-conjugated, MHC class II-associated peptides. This study for the first time directly demonstrates that hapten-peptides account for the majority of determinants recognized by trinitrophenyl (TNP)-specific CD4+ T lymphocytes. The sequences of those TNP carrier peptides do not have to be related to mouse proteins. Thus, we show that TNP-modified peptides derived from mouse IgG, pigeon cytochrome c or staphylococcal nuclease known to bind to I-Ab or from λ represser with specificity to I-Ad as well as TNP-proteins such as bovine serum albumin, ovalbumin or keyhole limpet hemocyanin all create class II-restricted hapten determinants for a number of TNP-specific T cell clones and hybridomas. All of these cells were induced with cells modified by trinitrobenzene sulfonic acid (TNBS). In addition, we present arguments indicating that individual TNP-specific helper T cells may cross-react with different TNP-peptides bound to identical class II molecules. Chemical treatment of antigen-presenting cells with TNCB or TNBS may thus result in a limited number of particularly repetitive immunodominant hapten epitopes. Immunodominant epitopes were also indicated by an overrepresentation of the TCR elements Vβ2 and Vα10 in I-Ab/TNP-specific T cells. Most importantly, however, we demonstrate that TNP attached to lysine 97 in the staphylococcal nuclease peptide 93–105 (i.e. a clearly “non-self” sequence) is able to prime mice for subsequent elicitation of contact sensitivity by TNCB in the absence of foreign protein. We take this to indicate that those TNP-peptide determinants defined by us as immuno-dominant are responsible for the induction of contact sensitivity to haptens.  相似文献   
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Changes of the arterial plasma osmolality and of the glucose concentration were followed during a 30 min period of graded hemorrhagic hypotension (80, 50, and 30 mmHg) in the cat. Bleeding evoked a significant plasma hyperosmolality at all three hypotension levels and the responses were quantitatively related to the degree of hypotension. An approximate steady state increase in the arterial plasma osmolality was reached about 20 min after the start of the bleeding and it then averaged 8, 20, and 25 mOsm/kg H2O at 80, 50, and 30 mmHg, respectively. Bleeding also evoked an increase in the plasma glucose concentration, which almost entirely accounted for the observed hyperosmolality, especially at 80 and 50 mmHg. In late stages of hypotension at 30 mmHg, elevated plasma lactate and potassium concentrations contributed to the overall hyperosmolality. — Previous hemorrhagic hypotension experiments at 50 mmHg (Järhult 1975 b) have shown that hyperosmolality serves as an important regulator of the plasma and extracellular fluid volumes during bleeding. The present results indicate that such an osmolar compensatory mechanism is operating over wide ranges of hemorrhagic hypotension.  相似文献   
107.
Radiologic evaluation of the skeleton and scanning electron microscopic studies of the teeth were performed on an infant boy with a lethal osteogenesis imperfecta (OI) syndrome who died at 10 mo of pneumonia. The skeletal findings included ribs that were focally expanded by fracture calluses, flat vertebral bodies, and wide limb bones. On fractured tooth surfaces, the enamel and dentin were normal as was the dentin calcification front. Although microscopic abnormalities have been noted in teeth from previously reported infants with lethal OI, a few studies also report infants with normal teeth. These differences in dental findings may indicate heterogeneity in OI lethal in infancy. Results of our study indicate that, until the primary biochemical defects in the OI syndromes are elucidated, examination of teeth from other infants with lethal OI and detailed evaluation of other clinical and skeletal features will aid in delineating heterogeneity and variation in expression in lethal OI.  相似文献   
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Summary Levels of three enzymes, leucine aminopeptidase (LAP), N-acetyl--D-glucosaminidase (NAG), and -glucuronidase (BGA) were measured in the urine of patients receiving hematologically toxic doses of iproplatin (a) with or (b) without pretreatment hydration. The maximum post-treatment increases in the levels of each of the enzymes were compared between these two groups of patients. In addition, the maximum increases in urinary enzyme levels in iproplatin-treated patients were compared with those in patients treated with 40 mg/m2 cisplatin, a known nephrotoxic agent.Increases in LAP levels after cisplatin treatment in the periods studied are significantly higher than those after iproplatin treatment (P0.05). No differences were found in the increases in BGA and NAG levels between iproplatin treatment and cisplatin treatment. No differences were found in the increases in levels of any of the enzymes between patients receiving iproplatin with pretreatment hydration and no prior hydration.The work reported in this paper was supported in part by grant CA-21071 from USPHS NCI and by Bristol Myers Co.  相似文献   
110.
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   
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