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排序方式: 共有996条查询结果,搜索用时 15 毫秒
51.
BACKGROUND: Extramedullary plasmacytomas (EMP) are plasma cell tumors in which by definition the primary tumor is extramedullary. Most of them are found in the upper aerodigestive tract. PATIENTS: In this study we describe 3 patients with EMP. The first case is a locally recurrent EMP with recurrent involvement of cervical lymph nodes. The first manifestation of EMP was 31 years ago. Hence, this is one of the longest clinical courses of recurrent EMP ever described in the literature. Case 2 is a locally aggressive recurrent EMP. Case 3 is a localized solitary EMP that could be successfully treated by surgery alone. RESULTS AND CONCLUSIONS: Different classifications of EMP described in the literature are discussed. If these classifications are applied to our cases neither the tumor stage nor the histological picture allow definite conclusions about the prognoses to be drawn. Metastases in regional lymph nodes do not necessarily mean a worse prognosis. Overall, compared to MM with a ten year survival rate of 18% the prognosis is more favorable in EMP with a ten year survival rate of 50%. After a generalized plasma cell neoplasia has been excluded EMP in the head and neck should be treated like a locally aggressive and potentially metastatic tumor. From our experiences we recommend a primary surgical therapy followed by radiation therapy if necessary. 相似文献
52.
Three sibs all presented in the early neonatal period with a salt-losing syndrome. The salt-losing form of congenital adrenal hyperplasia was diagnosed and appropriate treatment with glucocorticosteroids, mineralocorticosteroids, and additional dietary salt started. Although early life was maintained with difficulty, with age all 3 children required decreasing amounts of replacement steroids to maintain normal plasma electrolyte balance. They were reinvestigated at the ages of 15 years and 8 years (twins), when cortisol synthesis and metabolism proved normal, but aldosterone synthesis was blocked by deficiency of 18-dehydrogenase. Rational treatment of these cases of a salt-losing syndrome in which aldosterone synthesis alone is blocked due to lack of the enzyme 18-dehydrogenase requires the administration of a mineralocorticosteroid drug only. Since deoxycorticosterone (acetate or pivalate) requires intramuscular administration, as life-long therapy oral fludrocortisone is preferable. Although fludrocortisone has glucocorticoid activity, the "hydrocortisone equivalent" effect of the small dosage used was unlikely to inhibit either pituitary corticotrophin or growth hormone production. 相似文献
53.
Schulz HU Schürer M Krupp S Dammann HG Timm J Gessner U 《International journal of clinical pharmacology and therapeutics》2004,42(9):481-487
OBJECTIVE: This study investigated concentrations of ascorbic acid (ASC) in gastric mucosa, gastric juice, urine and plasma in healthy subjects under steady state and fasted conditions with and without concomitant administration of acetylsalicylic acid (ASA). MATERIAL AND METHODS: This was a prospective, randomized, double-blind, parallel-group study in healthy subjects. It has assessed the effects of a 6-day administration of 0.8 g ASA or 0.48 g ASC, 3 times daily and the combination of both on concentrations of ASC in gastric mucosa, gastric juice, urine and plasma. Treatments were switched after 6 days without any washout for assessment of compartment sensitivity to changes in study medication resulting in an overall 14-day study period. Each of the 3 treatment groups consisted of 15 subjects. RESULTS: ASC concentrations were highest in the gastric mucosa (251+/-11 microg/g), followed by gastric juice (29+/-6 microg/ml), plasma (10+/-0.2 microg/ml), and urine (5+/-1 microg/ml). On day 7, ASC concentrations in gastric mucosa, plasma and urine had increased in those groups receiving ASC and decreased in the group receiving ASA only. All differences were statistically significant and indicate an interaction with ASA. In gastric juice, differences in ASC concentrations between the treatment groups were not statistically significant between baseline and day 7. ASC concentrations in plasma were strongly correlated with corresponding ASC concentrations in gastric mucosa (r = 0.34) and urine (r = 0.83), as were ASC concentrations in gastric mucosa with ASC in urine (r = 0.28). CONCLUSIONS: The gastric mucosa is the largest depot of ASC in the human body with ASC concentrations 25 times higher than in plasma. In healthy subjects, clinically relevant doses of ASA reduced ASC concentrations in gastric mucosa by about 10% within 6 days resulting from antioxidative defense mechanisms. In patients with long-term ASA treatment or conditions with additional risks such as elderly subjects with unfavorable dietary conditions and impaired antioxidative protection, a protective adjunct administration of ASC appears to be beneficial. 相似文献
54.
Sonal Patel Olaf Dammann Camilia R Martin Elizabeth N Allred Alan Leviton 《Acta paediatrica (Oslo, Norway : 1992)》2011,100(1):36-41
Aim: To explore risk patterns for presumed and definite, early and late neonatal bacteremia. Methods: We studied 1106 extremely low gestational age newborns who survived until postnatal day 28. We defined early definite bacteremia as a positive bacterial culture in the first week and definite late bacteremia as a positive bacterial culture in week 2, 3 or 4. Bacteremia was presumed if antibiotics were given for more than 72 h despite negative blood cultures. Results: Risk patterns did not differ much for presumed and definite bacteremia in the first postnatal month. While maternal and pregnancy characteristics were associated with early bacteremia, neonatal comorbidities, especially NEC, were the main antecedents/correlates of late bacteremia. All four categories of bacteremia were associated with younger gestational age and lower birth weight. Infants with presumed and definite bacteremia had similar distributions of days of ventilation and oxygenation. Conclusion: Definite and presumed late bacteremias have rather similar risk patterns, while those of early and late bacteremia differ appreciably. 相似文献
55.
56.
W Oh DK Stevenson JE Tyson BH Morris CE Ahlfors G Jesse Bender RJ Wong R Perritt BR Vohr KP Van Meurs HJ Vreman A Das DL Phelps T Michael O’Shea RD Higgins 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(5):673-678
Objectives: To assess the influence of clinical status on the association between total plasma bilirubin and unbound bilirubin on death or adverse neurodevelopmental outcomes at 18–22 months corrected age in extremely low birth weight infants. Method: Total plasma bilirubin and unbound bilirubin were measured in 1101 extremely low birth weight infants at 5 ± 1 days of age. Clinical criteria were used to classify infants as clinically stable or unstable. Survivors were examined at 18–22 months corrected age by certified examiners. Outcome variables were death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death prior to follow‐up. For all outcomes, the interaction between bilirubin variables and clinical status was assessed in logistic regression analyses adjusted for multiple risk factors. Results: Regardless of clinical status, an increasing level of unbound bilirubin was associated with higher rates of death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss and death before follow‐up. Total plasma bilirubin values were directly associated with death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death before follow‐up in unstable infants, but not in stable infants. An inverse association between total plasma bilirubin and death or cerebral palsy was found in stable infants. Conclusions: In extremely low birth weight infants, clinical status at 5 days of age affects the association between total plasma bilirubin and death or adverse neurodevelopmental outcomes at 18–22 months of corrected age. An increasing level of UB is associated a higher risk of death or adverse neurodevelopmental outcomes regardless of clinical status. Increasing levels of total plasma bilirubin are directly associated with increasing risk of death or adverse neurodevelopmental outcomes in unstable, but not in stable infants. 相似文献
57.
Leviton Alan Joseph Robert M. Fichorova Raina N. Allred Elizabeth N. Gerry Taylor H. Michael O’Shea T. Dammann Olaf 《Journal of neuroimmune pharmacology》2019,14(2):188-199
Journal of Neuroimmune Pharmacology - We evaluated the relationship between blood levels of inflammatory and neurotrophic proteins during the first postnatal month in 692 children born before the... 相似文献
58.
Sascha Pawlowski Martina Dammann Lennart Weltje Samantha Champ Michael Mathis Douglas J. Fort 《Journal of applied toxicology : JAT》2019,39(8):1164-1172
The amphibian metamorphosis assay represents an OECD Level 3 and EDSP Tier 1 ecotoxicity test assessing thyroid activity of chemicals in African clawed frog (Xenopus laevis). To evaluate the effectiveness of snout‐vent length (SVL) normalization of hindlimb length (HLL), correlation between the HLL and SVL or body weight was evaluated in the control groups of 10 individual studies from three laboratories. Two studies required separate analysis of the Nieuwkoop‐Faber (NF) stage ≤60 and >60 animals creating a total of 12 data sets. On study day 7, significant positive correlation between HLL and SVL or body weight was observed in eight and seven of the 10 data sets, respectively (r = 0.608‐0.843 and 0.583‐0.876). On study day 21, significant positive correlation between HLL and SVL or body weight was found in three and four of the 12 data sets, respectively (r = 0.452, 0.480 and 0.553 and r = 0.621, 0.546, 0.564 and 0.378). Significant positive correlation between HLL and SVL was found in three of five studies, including ≤NF stage 60 data (r = 0.564, 0.546 and 0.621). In one of eight studies, including >NF stage 60 data, the positive correlation between HLL and body weight was determined (r = 0.378). Negative or no correlation between HLL and SVL or body weight was found in the other late stage data sets. Therefore, use of SVL‐normalized HLL to assess thyroid‐mediated effects in X. laevis tadpoles is not warranted. HL stage relative to body stage should be considered. 相似文献
59.
Vineeta Khare Alex Lyakhovich Kyle Dammann Michaela Lang Melanie Borgmann Boris Tichy Sarka Pospisilova Gloria Luciani Christoph Campregher Rayko Evstatiev Maren Pflueger Harald Hundsberger Christoph Gasche 《Biochemical pharmacology》2013,85(2):234-244
Mesalamine (5-ASA) is widely used for the treatment of ulcerative colitis, a remitting condition characterized by chronic inflammation of the colon. Knowledge about the molecular and cellular targets of 5-ASA is limited and a clear understanding of its activity in intestinal homeostasis and interference with neoplastic progression is lacking. We sought to identify molecular pathways interfered by 5-ASA, using CRC cell lines with different genetic background. Microarray was performed for gene expression profile of 5-ASA-treated and untreated cells (HCT116 and HT29). Filtering and analysis of data identified three oncogenic pathways interfered by 5-ASA: MAPK/ERK pathway, cell adhesion and β-catenin/Wnt signaling. PAK1 emerged as a consensus target of 5-ASA, orchestrating these pathways. We further investigated the effect of 5-ASA on cell adhesion. 5-ASA increased cell adhesion which was measured by cell adhesion assay and transcellular-resistance measurement. Moreover, 5-ASA treatment restored membranous expression of adhesion molecules E-cadherin and β-catenin. Role of PAK1 as a mediator of mesalamine activity was validated in vitro and in vivo. Inhibition of PAK1 by RNA interference also increased cell adhesion. PAK1 expression was elevated in APCmin polyps and 5-ASA treatment reduced its expression. Our data demonstrates novel pharmacological mechanism of mesalamine in modulation of cell adhesion and role of PAK1 in APCmin polyposis. We propose that inhibition of PAK1 expression by 5-ASA can impede with neoplastic progression in colorectal carcinogenesis. The mechanism of PAK1 inhibition and induction of membranous translocation of adhesion proteins by 5-ASA might be independent of its known anti-inflammatory action. 相似文献
60.
Chukwudebe A Privalle L Reed A Wandelt C Contri D Dammann M Groeters S Kaspers U Strauss V van Ravenzwaay B 《Food and chemical toxicology》2012,50(3-4):956-971
This subchronic duration feeding study evaluated the nutritional and health status of rats fed diets containing CV127 at incorporation levels of 11% and 33%. For control comparisons, rats were also exposed to similar incorporation levels of the near isogenic conventional soybean variety (Conquista) and two other conventional soybean varieties (Monsoy, Coodetec). In spite of phenotypic differences among these four soybean varieties, there were no quantitative differences in their respective proximate and other compositional properties, including proteins, amino acids, antinutrients and nutritional cofactors. All diets were prepared by blending the respective processed soybean meal with ground Kliba maintenance meal at high (33%) and low (11%) incorporation levels, and the blended diets were fed to Wistar rats for about 91 days. Although there were some isolated parameters indicating statistically significant changes, these lacked consistency and a plausible mechanism and were thus assessed to be incidental. The totality of results demonstrate that CV127 soybeans are similar with respect to their nutritional value and systemic effects as its near isogenic conventional counterpart, as well as other conventional soybean varieties. Hence, introduction of AHAS gene into soybeans does not substantially alter its compositional properties, nor adversely affect its nutritional or safety status to mammals. 相似文献