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901.
902.
Charlotte A. Raby Maria C. Morganti-Kossmann Thomas Kossmann Philip F. Stahel M. Desiree Watson Lori M. Evans †Pankaj D. Mehta Katharyn Spiegel ‡Yu-Min Kuo ‡Alex E. Roher Mark R. Emmerling 《Journal of neurochemistry》1998,71(6):2505-2509
Abstract: The β-amyloid peptides, Aβ1-42 and Aβ1-40, were quantified in ventricular CSF taken daily for up to 3 weeks from six individuals with severe traumatic brain injury (TBI). There was considerable interindividual variability in the levels of Aβ peptides, but in general Aβ1-42 levels equalled or exceeded those of Aβ1-40. Averaging the daily totals of our trauma cohort revealed that the levels of Aβ1-42 and Aβ1-40 rose after injury, peaking in the first week and then declining toward control levels over the next 2 weeks. Aβ1-42 levels were on average two to three times higher in the trauma cohort than in CSF from nontrauma samples. Compared with nontrauma samples, the Aβ1-40/Aβ1-42 ratio decreased about fivefold in the trauma patients, further indicative of increased Aβ1-42 levels. The ratio remained low at all time points studied. No change was measured in the levels of β-amyloid precursor protein during the same interval. These results suggest that Aβ1-42 becomes elevated in the CSF after severe brain trauma. 相似文献
903.
Relative Importance of Rotavirus-Specific Effector and Memory B Cells in Protection against Challenge 总被引:5,自引:2,他引:3
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Charlotte A. Moser Sarah Cookinham Susan E. Coffin H. Fred Clark Paul A. Offit 《Journal of virology》1998,72(2):1108-1114
Adult BALB/c mice were orally inoculated with murine (strain EDIM), simian (strain RRV), or bovine (strain WC3) rotavirus. Six or 16 weeks after inoculation, mice were challenged with EDIM. At the time of challenge and in the days immediately following challenge, production of rotavirus-specific immunoglobulin A (IgA), IgG, and IgM by small intestinal lamina propria lymphocytes (LPL) was determined by fragment culture, and quantities of virus-specific antibodies at the intestinal mucosal surface were determined by intestinal lavage. Mice immunized with EDIM were completely protected against EDIM challenge both 6 and 16 weeks after immunization. Protection was associated with production of high levels of IgA by LPL and detection of virus-specific IgA at the intestinal mucosal surface. In addition, animals immunized and later challenged with EDIM did not develop a boost in antibody responses, suggesting that they were also not reinfected. We also found that in mice immunized with nonmurine rotaviruses, (i) quantities of virus-specific IgA generated following challenge were greater 16 weeks than 6 weeks after immunization, (ii) immunization enhanced the magnitude but did not hasten the onset of production of high quantities of virus-specific IgA by LPL after challenge, and (iii) immunization induced partial protection against challenge; however, protection was not associated with either production of virus-specific antibodies by LPL or detection of virus-specific antibodies at the intestinal mucosal surface. 相似文献
904.
Anna Björklund Charlotte Bjuggren Magnus Dalemo Ulf Sonesson 《Journal of Industrial Ecology》1999,3(4):43-58
The environmental impact of the management of biodegradable waste in Stockholm, based mainly on incineration and landfilling, was compared to systems with significant nutrient recycling; large-scale composting, anaerobic digestion, and separate collection and utilization of urine. The systems' emissions, residual products, energy turnover, and resource consumption were evaluated from a life-cycle perspective, using a computerized model, ORWARE (ORganic WAste REsearch model).
Transportation was of relatively low importance to overall environmental impact, even at high rates of nutrient recycling. This is remarkable considering the geographical setting of Stockholm, with high population density and little nearby farmland. Ancillary systems, such as generation of electricity and district heating, were crucial for the overall outcome.
Increased recycling of nutrients in solid biodegradable waste in Stockholm can reduce net environmental impact, whereas separation of human urine to be spread as fertilizer cannot yet be introduced without increased acidification. Increased nutrient recycling from solid biodegradable waste inevitably increases spreading of metals on arable land. Urine is by far the least contaminated residual product. Spreading of all other residuals would be limited by their metal content. 相似文献
Transportation was of relatively low importance to overall environmental impact, even at high rates of nutrient recycling. This is remarkable considering the geographical setting of Stockholm, with high population density and little nearby farmland. Ancillary systems, such as generation of electricity and district heating, were crucial for the overall outcome.
Increased recycling of nutrients in solid biodegradable waste in Stockholm can reduce net environmental impact, whereas separation of human urine to be spread as fertilizer cannot yet be introduced without increased acidification. Increased nutrient recycling from solid biodegradable waste inevitably increases spreading of metals on arable land. Urine is by far the least contaminated residual product. Spreading of all other residuals would be limited by their metal content. 相似文献
905.
Jahanara Begum-Hasan Mary Senterman Peter Gillett Charlotte Laplante Branchaud Beverley E. Pearson Murphy 《In vitro cellular & developmental biology. Animal》1993,29(6):505-511
Summary Fetal bovine serum (FBS) is frequently used to supplement chemically defined media such as Ham’s F10 when studying placental
explant cultures. However in vitro production of hormones is usually declining by the 2nd or 3rd day and is short-lived (7
to 10 days). In this study we explored the use of human maternal serum (HMS) from early gestation as the medium supplement
to Ham’s F10. Early placental hormone production was compared using two concentrations of FBS and HMS. On Day 3 of incubation,
progesterone production in 10% HMS was 12-fold increased over that in 10% FBS, estradiol production was increased 10-fold,
and βhCG production more than 3-fold. When the serum concentrations were increased to 40%, the results in all cases were similar
to those at 10%. Preliminary characterization studies revealed that the stimulatory activity of HMS is heat-labile, neither
extractable into organic solvent (diethyl ether) nor dialyzable, suggesting that it is protein in nature. In a long-term incubation,
compared with FBS (7 days), HMS permitted survival of culture up to 30 days, judged both histologically and biochemically.
We conclude that HMS provides substance(s), probably protein in nature, not present in FBS or non-pregnant human serum, which
are important for human placental viability and function in vivo. 相似文献
906.
907.
Summary Injections of serum from human patients with cystic fibrosis into adult rats caused pronounced structural modifications and increased mitotic rate in the parotid gland. Mitotic rate was increased from a low level of 0.02/1,000 acinar cells in parotid glands of adult rats to 6.5/1,000 acinar cells after 2 or 3 days of serum injection. At the light and electron microscopic levels, significant acinar cell atrophy and degranulation were observed. Cellular necrosis, and increases in quantity of lysosome-like dense bodies, mast cells, and macrophages were also detected. These changes are suggestive of tissue response to injurious foreign protein. Furthermore, the fact that normal sera pronounced the same kind of effects (but greatly reduced in extent) strengthens the view that these effects result from the immunologic response of the host organ to foreign antigen. Since, however, the responses of the rat parotid to cystic fibrosis serum were considerably more marked than those elicited by normal serum, the rat parotid may thus have potential usefulness in assaying for the presence of human cystic fibrosis factor.This work was supported in part by U.S.P.H.S. Grant DE 02110The authors wish to thank Dr. Alexander Spock, Cystic Fibrosis Center, Duke University Medical Center, Durham, North Carolina, and Dr. Ralph Tiller, Children's Hospital, University of Alabama Medical Center, for generously supplying blood from patients with cystic fibrosis. The authors also want to thank Dr. A. Siegel, Department of Pathology, University of Alabama Medical Center, and Mr. R. Siegel, for determinations of serum catecholamine levels 相似文献
908.
909.
Jia Li Yadong Xue Charlotte E. Hacker Yu Zhang Ye Li Wei Cong Lixiao Jin Gang Li Bo Wu Diqiang Li Yuguang Zhang 《Ecology and evolution》2021,11(23):17202
Assessing species’ vulnerability to climate change is a prerequisite for developing effective strategies to reduce emerging climate‐related threats. We used the maximum entropy algorithm (MaxEnt model) to assess potential changes in suitable snow leopard (Panthera uncia) habitat in Qinghai Province, China, under a mild climate change scenario. Our results showed that the area of suitable snow leopard habitat in Qinghai Province was 302,821 km2 under current conditions and 228,997 km2 under the 2050s climatic scenario, with a mean upward shift in elevation of 90 m. At present, nature reserves protect 38.78% of currently suitable habitat and will protect 42.56% of future suitable habitat. Current areas of climate refugia amounted to 212,341 km2 and are mainly distributed in the Sanjiangyuan region, Qilian mountains, and surrounding areas. Our results provide valuable information for formulating strategies to meet future conservation challenges brought on by climate stress. We suggest that conservation efforts in Qinghai Province should focus on protecting areas of climate refugia and on maintaining or building corridors when planning for future species management. 相似文献
910.
Christopher J. Knüsel Charlotte A. Roberts Anthea Boylston 《American journal of physical anthropology》1996,100(3):427-433
A rare, activity-related lesion, the clay-shoveller's fracture, was identified during osteological analysis in three human populations dating from the Roman to the later Medieval period in England, circa fourth to 14th centuries A.D. The prevalence of this fracture in these populations suggests an osteological indicator for several possible manual activities, but also one that may be the result of a long-standing human subsistence adaptation requiring digging in the soil. Since males as opposed to females appear to be preferentially affected, the occurrence of such injuries has the potential to provide an insight into the sexual division of labor in earlier human populations. © 1996 Wiley-Liss, Inc. 相似文献