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991.
992.
993.
A 13 yr old male with acute lymphoblastic leukaemia who received bilevel positive airway pressure ventilation via a face mask for post-transplant pneumonitis developed subcutaneous emphysema, radiographic evidence of pulmonary interstitial emphysema, pneumomediastinum and 6 h later, right hemiparesis and focal livedo reticularis. This case illustrates that severe barotrauma may complicate noninvasive bilevel positive airway pressure ventilation. 相似文献
994.
M Toborek EM Blanc S Kaiser MP Mattson B Hennig 《Canadian Metallurgical Quarterly》1997,38(10):2155-2167
Diet-derived lipids may influence cytokine-mediated endothelial cell dysfunction, including TNF-induced apoptosis. To test this hypothesis, oxidative stress, intracellular calcium levels, endothelial barrier function, cell viability, and apoptosis were measured in vascular endothelial cells treated with 90 microM linoleic acid (18:2, n-6) and/or 20 ng/mL TNF (100 U/mL). For short-term exposure, endothelial cells were exposed to 18:2 for 6 h or to TNF for 1.5 h. For long-term exposure, endothelial cultures were treated with 18:2 for 24 h and with TNF for 19.5 h. In cells exposed to 18:2 + TNF, pretreatment with 18:2 began 4.5 h before additional exposure to TNF for either 1.5 h (short-term exposure) or 19.5 h (long-term exposure). After treatment, endothelial cultures were washed and incubated with maintenance medium for up to 4 days. Although initial treatment with TNF or 18:2 significantly increased oxidative stress and intracellular calcium levels, only exposure to TNF induced apoptosis in cultured endothelial cells. Furthermore, the combined exposure to 18:2 + TNF potentiated TNF-induced apoptosis. Additional treatments with BAPTA-AM, n-propyl gallate, vitamin E, and with aurintricarboxylic acid partially protected against TNF- or 18:2 + TNF-induced apoptosis. The present study suggests that changes in the cellular lipid environment may markedly influence local TNF-induced events in the vascular endothelium, including endothelial cell apoptosis. Such mechanisms may play a role in the damage and death of vascular endothelial cells in atherosclerosis. 相似文献
995.
OR Kaaden U Truyen MH Groschup A Uysal E Kaiser H Kretzschmar T Bogumil J Pohlenz H Diringer P Steinhagen 《Canadian Metallurgical Quarterly》1994,41(4):294-304
Bovine spongiform encephalopathy (BSE) has been described as an epidemic central nervous disorder in cattle from the United Kingdom. The disease is thought to have emerged by an interspecies transmission of the scrapie agent of sheep to cattle, after feeding scrapie-contaminated meat and bone meal (MBM). The disease has caused substantial economic losses for the British cattle industry. Because of strict veterinary regulations for the import of adult British cattle by the European Union and for MBM by most of the member states the spread of BSE to continental Europe could be efficiently controlled, and only few cases have been described outside the UK. Here we report the first German case of BSE diagnosed in a Scottish Highland cow. The affected cow was imported into Germany before the import ban for cattle from the UK was implemented. BSE was confirmed by histopathology, immunohistochemistry, animal experiments, immunoblotting and by electron microscopic detection of scrapie-associated fibrils (SAFs). 相似文献
996.
AS Loginov BN Matiushin SM Chebanov VI Reshetniak 《Canadian Metallurgical Quarterly》1998,70(4):40-42
23 patients with benign prostatic hyperplasia (BPH) aged 60-82 years underwent transurethral resection (TUR) of the prostate in different periods after thermal treatment which had appeared uneffective or brought complications. In the performance of the endoscopic techniques we found macroscopic changes of the prostatic parts of the urethra and bladder cervix characteristic for certain thermal impact (energy, power, site of exposure). Intraoperative bleeding of prostatic tissue was also different depending primarily on the time which had passed after the thermal treatment. Minimal bleeding occurred at least 3 months after the thermotherapy. Thus, thermal treatment of the prostate can be used in combined treatment of BPH for reducing intra- and postoperative hemorrhage due to subsequent TUR. Among the methods of thermal therapy, transurethral microwave thermotherapy is preferable as minimally invasive and deeply penetrating into the depth of the prostatic gland with maximal effect. TUR of the prostate should be performed not earlier than 3 months after thermotherapy which is indicated only for patients at high risk of intraoperative hemorrhage because of unaffected circulation. Therefore, it is desirable to include transrectal dopplerography of the prostate to urological examination of BPH patients. 相似文献
997.
D. G. Kipshidze H. P. Schenk A. Fissel U. Kaiser J. Schulze Wo. Richter M. Weihnacht R. Kunze J. Kräusslich 《Semiconductors》1999,33(11):1241-1246
The results of using molecular-beam epitaxy for growing piezoelectric AlN films on Si (111) substrates suitable for device
applications are reported. The technological conditions for growth of stoichiometric AlN by controlling the surface reconstruction
occurring under various thermodynamic conditions on the growth surface are determined. The films of the hexagonal polytype
of AlN possess high crystalline perfection and an atomically smooth epitaxial surface. The mechanism for relaxation of the
AlN crystal lattice over a distance of one monolayer from the heterojunction is found. It is demonstrated that the AlN film
is piezoelectric. Investigations of the temporal characteristics of a SAW attest to a low level of scattering of the wave
during propagation. The electromechanical coupling constant is measured in interdigital transducer geometry (λ=16 mm) and
is found to be 0.07 % at a frequency f=286 MHz, in good agreement with the theoretical value for a 1.04-μm-thick AlN film.
Fiz. Tekh. Poluprovodn. 33, 1372–1378 (November 1999) 相似文献
998.
The controlled growth of SiC heteropolytypic structures consisting of hexagonal (-) and cubic (3C-) polytypes has been performed by solid-source molecular beam epitaxy. On on-axis substrates, 4H/3C/4H-SiC(0001) and 6H/3C/6H-SiC(0001) structures were obtained by first growing some nanometers thick 3C-SiC layer at lower temperatures (1550 K) and Si-rich conditions, and subsequent growth of -SiC on top of the 3C-SiC layer at higher temperatures (1600 K) under more C-rich conditions. On off-axis substrates, multi-heterostructures consisting of 4H/3C- or 6H/3C-stacking sequences were also obtained by first nucleating selectively wire-like 3C-SiC nuclei on the terraces of well-prepared off-axis -SiC(0001) substrates at low T (<1500 K). Next, SiC was grown further in a step-flow growth mode at higher T and Si-rich condition. After the growth many wire-like regions consisting of 3C-SiC were found within the hexagonal SiC layer material matrix indicating a simultaneous step-flow growth of both the cubic and the hexagonal SiC material. 相似文献
999.
1000.
E96V Mutation in the Kdelr3 Gene Is Associated with Type 2 Diabetes Susceptibility in Obese NZO Mice
Delsi Altenhofen Jenny Minh-An Khuong Tanja Kuhn Sandra Lebek Sarah Grigk Katharina Kaiser Christian Binsch Kerstin Griess Birgit Knebel Bengt-Frederik Belgardt Sandra Cames Samaneh Eickelschulte Torben Stermann Axel Rasche Ralf Herwig Jürgen Weiss Heike Vogel Annette Schürmann Alexandra Chadt Hadi Al-Hasani 《International journal of molecular sciences》2023,24(1)
Type 2 diabetes (T2D) represents a multifactorial metabolic disease with a strong genetic predisposition. Despite elaborate efforts in identifying the genetic variants determining individual susceptibility towards T2D, the majority of genetic factors driving disease development remain poorly understood. With the aim to identify novel T2D risk genes we previously generated an N2 outcross population using the two inbred mouse strains New Zealand obese (NZO) and C3HeB/FeJ (C3H). A linkage study performed in this population led to the identification of the novel T2D-associated quantitative trait locus (QTL) Nbg15 (NZO blood glucose on chromosome 15, Logarithm of odds (LOD) 6.6). In this study we used a combined approach of positional cloning, gene expression analyses and in silico predictions of DNA polymorphism on gene/protein function to dissect the genetic variants linking Nbg15 to the development of T2D. Moreover, we have generated congenic strains that associated the distal sublocus of Nbg15 to mechanisms altering pancreatic beta cell function. In this sublocus, Cbx6, Fam135b and Kdelr3 were nominated as potential causative genes associated with the Nbg15 driven effects. Moreover, a putative mutation in the Kdelr3 gene from NZO was identified, negatively influencing adaptive responses associated with pancreatic beta cell death and induction of endoplasmic reticulum stress. Importantly, knockdown of Kdelr3 in cultured Min6 beta cells altered insulin granules maturation and pro-insulin levels, pointing towards a crucial role of this gene in islets function and T2D susceptibility. 相似文献