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1.
JF Favarel-Garrigues F Sztark ME Petitjean M Thico?pé P Lassié P Dabadie 《Canadian Metallurgical Quarterly》1996,82(2):312-316
Protective immunity against infection with Mycobacterium tuberculosis is imparted by T cells rather than antibodies, but B cells can play a role as antigen-presenting cells and in granuloma formation. We re-evaluated the role of B cells in the course of tuberculous infection in mu-chain knock-out (Ig-) mice. Surprisingly, the organs of M. tuberculosis-infected Ig- mice were found to have three- to eight-fold elevated counts of viable bacilli compared with normal littermates at 3-6 weeks post-infection. Splenic interferon-gamma responses to whole antigen were unimpaired, whilst proliferation to certain mycobacterial peptides was found to be diminished. However, bacille Calmette-Guérin (BCG) vaccination significantly reduced the infection in Ig- mice. The mechanisms by which B cells can influence primary tuberculous infection need further study. 相似文献
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SG Rijpkema RG Herbes N Verbeek-De Kruif JF Schellekens 《Canadian Metallurgical Quarterly》1996,117(3):563-566
Epiglottic disruption is an uncommon injury usually associated with significant supraglottic trauma. This injury may be overlooked because of the difficulty in examining the larynx or other associated severe injuries. We present two cases of clinically unsuspected epiglottic disruption that were first seen on MR images of the neck. 相似文献
3.
BS Kendrick BS Chang T Arakawa B Peterson TW Randolph MC Manning JF Carpenter 《Canadian Metallurgical Quarterly》1997,94(22):11917-11922
Understanding the mechanism for sucrose-induced protein stabilization is important in many diverse fields, ranging from biochemistry and environmental physiology to pharmaceutical science. Timasheff and Lee [Lee, J. C. & Timasheff, S. N. (1981) J. Biol. Chem. 256, 7193-7201] have established that thermodynamic stabilization of proteins by sucrose is due to preferential exclusion of the sugar from the protein's surface, which increases protein chemical potential. The current study measures the preferential exclusion of 1 M sucrose from a protein drug, recombinant interleukin 1 receptor antagonist (rhIL-1ra). It is proposed that the degree of preferential exclusion and increase in chemical potential are directly proportional to the protein surface area and that, hence, the system will favor the protein state with the smallest surface area. This mechanism explains the observed sucrose-induced restriction of rhIL-1ra conformational fluctuations, which were studied by hydrogen-deuterium exchange and cysteine reactivity measurements. Furthermore, infrared spectroscopy of rhlL-1ra suggested that a more ordered native conformation is induced by sucrose. Electron paramagnetic resonance spectroscopy demonstrated that in the presence of sucrose, spin-labeled cysteine 116 becomes more buried in the protein's interior and that the hydrodynamic diameter of the protein is reduced. The preferential exclusion of sucrose from the protein and the resulting shift in the equilibrium between protein states toward the most compact conformation account for sucrose-induced effects on rhIL-1ra. 相似文献
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Tracheobronchial stent insertion is a relatively new technique used to palliate or cure central airways obstruction. When performed by experienced thoracic endoscopists, this procedure is both safe and effective, even if complications of indwelling stents may require repeat endoscopic intervention. Although proven clinically beneficial to many patients, airway prostheses have not yet been the subject of large comparative case studies or randomized controlled investigations. Reports are often experiential and anecdotal. Further research is needed to determine the effects of stenting on survival in patients with malignant airway disease and its degree of success in patients with benign airway strictures. Only then will airway stents truly deserve their place alongside other therapies for tracheobronchial obstruction. 相似文献
8.
JF Levine CS Apperson P Howard M Washburn AL Braswell 《Canadian Metallurgical Quarterly》1997,34(6):594-598
Previously archived museum specimens of lizards collected throughout North Carolina were examined for Ixodes scapularis (Say). Lizards (n = 1,349) collected in 80 of North Carolina's 100 counties were examined. Lizards with ticks were collected in 23 (29%) of the 80 counties from which lizards were examined. I. scapularis was detected on 8.7% (n = 117) of the lizards and was the sole species of tick obtained from lizards. Immature ticks were most frequently found on the southeastern five-lined skink, Eumeces inexpectatus, and the eastern glass lizard, Ophisaurus ventralis. Larvae were most frequently found on the six-lined racerunner, Cnemidophorus sexlineatus. One C. sexlineatus harbored 177 larvae and 2 nymphs. Nymphs were most frequently observed on E. inexpectatus. The majority of counties (chi 2, P < 0.01) where ticks were found on lizards were in the Coastal Plain. 相似文献
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Y Yang SE Raper JA Cohn JF Engelhardt JM Wilson 《Canadian Metallurgical Quarterly》1993,90(10):4601-4605
Cystic fibrosis (CF) is an inherited disease of epithelial cell ion transport that is associated with pathology in multiple organ systems, including lung, pancreas, and liver. As treatment of the pulmonary manifestations of CF has improved, management of CF liver disease has become increasingly important in adult patients. This report describes an approach for treating CF liver disease by somatic gene transfer. In situ hybridization and immunocytochemistry analysis of rat liver sections indicated that the endogenous CFTR (cystic fibrosis transmembrane conductance regulator) gene is primarily expressed in the intrahepatic biliary epithelial cells. To specifically target recombinant genes to the biliary epithelium in vivo, recombinant adenoviruses expressing lacZ or human CFTR were infused retrograde into the biliary tract through the common bile duct. Conditions were established for achieving recombinant gene expression in virtually all cells of the intrahepatic bile ducts in vivo. Expression persisted in the smaller bile ducts for the duration of the experiment, which was 21 days. These studies suggest that it may be feasible to prevent CF liver disease by genetically reconstituting CFTR expression in the biliary tract, using an approach that is clinically feasible. 相似文献