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111.
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Margaret A. Judd Charlotte A. Roberts 《American journal of physical anthropology》1999,109(2):229-243
Farming is among the three most hazardous occupations in modern society and perhaps also held a similar position during the medieval period. The goal of this study was to determine if there is a significant difference in frequencies and patterns of longbone fracture trauma observed between rural and urban activity bases that distinguish farming as a particularly dangerous occupation during the medieval period. The longbones of 170 individuals excavated from Raunds, a rural medieval British site (10th–12th centuries AD) were examined for fractures and compared to data collected from four contemporary British medieval sites, one rural and three urban. The fracture frequency for the Raunds individuals (19.4%) was significantly different from the urban sites (4.7–5.5%). Female fractures were characterized by injury to the forearm, while the males were predisposed to diverse fracture locations. Clinical research provided a source of documented farm-related trauma from North America and Europe where the crops and animals raised, the manual chores performed, and the equipment used in traditional or small-scale farms have changed little in form or function since the medieval period. Nonmechanized causes of injury contribute to approximately 40% of all modern farm-related injuries and are attributed to falls from lofts and ladders, animal assaults and bites, and falls from moving vehicles. These hazardous situations were also present in the medieval period and may explain some of the fracture trauma from the rural sites. A high fracture frequency for both medieval males and females is significantly associated with farming subsistence when compared to craft-orientated urban dwellers. Am J Phys Anthropol 109:229–243, 1999. © 1999 Wiley-Liss, Inc. 相似文献
114.
Inactivity, exercise, and visceral fat. STRRIDE: a randomized, controlled study of exercise intensity and amount. 总被引:3,自引:0,他引:3
Cris A Slentz Lori B Aiken Joseph A Houmard Connie W Bales Johanna L Johnson Charles J Tanner Brian D Duscha William E Kraus 《Journal of applied physiology》2005,99(4):1613-1618
Despite the importance of randomized, dose-response studies for proper evaluation of effective clinical interventions, there have been no dose-response studies on the effects of exercise amount on abdominal obesity, a major risk factor for metabolic syndrome, diabetes, and cardiovascular disease. One hundred seventy-five sedentary, overweight men and women with mild to moderate dyslipidemia were randomly assigned to participate for 6 mo in a control group or for approximately 8 mo in one of three exercise groups: 1) low amount, moderate intensity, equivalent to walking 12 miles/wk (19.2 km) at 40-55% of peak oxygen consumption; 2) low amount, vigorous intensity, equivalent to jogging 12 miles/wk at 65-80% of peak oxygen consumption; or 3) high amount, vigorous intensity, equivalent to jogging 20 miles/wk (32.0 km). Computed tomography scans were analyzed for abdominal fat. Controls gained visceral fat (8.6 +/- 17.2%; P = 0.001). The equivalent of 11 miles of exercise per week, at either intensity, prevented significant accumulation of visceral fat. The highest amount of exercise resulted in decreased visceral (-6.9 +/- 20.8%; P = 0.038) and subcutaneous (-7.0 +/- 10.8%; P < 0.001) abdominal fat. Significant gains in visceral fat over only 6 mo emphasize the high cost of continued inactivity. A modest exercise program, consistent with recommendations from the Centers for Disease Control/American College of Sports Medicine (CDC/ACSM), prevented significant increases in visceral fat. Importantly, a modest increase over the CDC/ACSM exercise recommendations resulted in significant decreases in visceral, subcutaneous, and total abdominal fat without changes in caloric intake. 相似文献
115.
In this study, adaptive immune response was investigated in farmed southern bluefin tuna, Thunnus maccoyii, infected with a sanguinicolid Cardicola forsteri. A cohort (Cohort2005) of southern bluefin tuna was sampled between March 2005 and August 2006. Samples were taken at the transfer of wild caught tuna to sea cages and then at regular intervals. Parasite intensity, abundance and prevalence data were recorded. An ELISA was developed to detect and quantify an antibody response against the blood fluke in southern bluefin tuna serum. Intensity and prevalence of the blood fluke were shown to peak in May 2005 at 10.9 flukes per infected fish (SE = 1.72) and 97.5% prevalence and then decreased to low prevalence (10%) and intensity (1.0). There were no significant changes in prevalence or intensity in 2006. Antibody titres and seroprevalence increased from 1.37 U μl−1 and 10% at transfer in March 2005 to reach a peak in December 2005 of 25.86 U μl−1 (SE = 6.26 U μl−1) and 66.66%. No significant changes were observed in antibody titres for the same cohort of fish during 2006. Parasitological and serological values from Cohort2005 were compared to a 2006 cohort (Cohort2006) in March 2006 and August 2006 to determine if prior infection in Cohort2005 elicited any protection against infection in 2006. Although significant differences were not observed in intensities between cohorts it was shown that Cohort2005 had significantly lower abundances and prevalences of blood fluke infection than Cohort2006. Although there was no significant difference in mean antibody titres between cohorts in March 2006, the mean antibody titre of Cohort2006 was significantly greater than that of Cohort2005 in August 2006. No significant differences were observed in seroprevalence. This is one of the few studies to demonstrate the development of acquired resistance in fish against a parasite in an aquaculture environment under natural infection conditions. 相似文献
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Some populations in Washington's Puget Sound area consume much more seafood than the general population. Mean consumption rates are 61?g/person/day for the Tulalip and Squaxin Island Tribes and 117.2?g/person/day for Asian and Pacific Islanders (API). There is concern about possible health risks from seafood PCB exposure for these groups, but exposure evaluation is difficult due to inadequacies of environmental data. Available seafood PCB data were matched to results from recent seafood consumption surveys. To rate quality of matches and identify data gaps, a ranking system based on species specificity, data quality, and location compatibility was developed. Sensitivity of total PCB and congenerspecific PCB testing (for use in TCDD toxic equivalency approaches) necessary for cancer risk assessment was explored and included in the ranking scheme. For the Squaxin Tribe, appropriate total PCB data for risk assessment were available for 58% of seafood consumed, which is dominated by local salmon. For API, appropriate total PCB data were identified for only 4% of seafood consumed, which is dominated by commercial shellfish. Insufficient sensitivity of commercial seafood PCB analysis and overall lack of sufficiently sensitive PCB congener analysis are major gaps in ability to characterize PCB exposure and risk for these groups. 相似文献
118.
Xin Shi Nicole J LeCapitaine Xiaowen L Rudner Sanbao Ruan Judd E Shellito 《Respiratory research》2009,10(1):57
Background
Apoptosis of lymphocytes is important in the termination of an immune response to infection but has also been shown to have detrimental effects in animal models of systemic infection and sepsis. We sought to characterize lymphocyte apoptosis in an animal model of pneumonia due to Pneumocystis murina, an infection localized to the lungs.Methods
Control mice and mice depleted of CD4+ lymphocytes were inoculated with Pneumocystis. Apoptosis of lung and spleen lymphocytes was assayed by flow cytometry and PCR assay of apoptotic proteins.Results
In control mice, apoptosis of lung lymphocytes was maximal just after the infection was cleared from lung tissue and then declined. However, in CD4-depleted mice, apoptosis was also upregulated in recruited lymphocytes in spite of progressive infection. In splenic lymphocytes, apoptosis was observed early at 1 week after inoculation and then declined. Apoptosis of lung lymphocytes in control mice was associated with a decrease in mRNA for Bcl-2 and an increase in mRNA for Bim. In CD4-depleted mice, lavaged CD8+ cells did change intracellular Bcl-2 but showed increased mRNA for Bim.Conclusion
Apoptosis of both pulmonary and extrapulmonary lymphocytes is part of the normal host response to Pneumocystis but is also triggered in CD4-deficient animals with progressive infection. In normal mice apoptosis of pulmonary lymphocytes may serve to terminate the immune response in lung tissue. Apoptosis of lung lymphocytes takes place via both the intrinsic and extrinsic apoptotic pathways and is associated with changes in both pro- and anti-apoptotic proteins. 相似文献119.
Invasive fungal infections are becoming increasingly important in the management of critically ill and immunocompromised patients.
As organ and stem cell transplantation becomes more prominent and immune therapies are employed for diseases such as rheumatoid
arthritis and plaque psoriasis, the population of patients at risk continues to grow. Many invasive fungal infections are
associated with extremely high mortality rates. Antifungal options are limited and novel therapies are intriguing as we attempt
to improve patient outcomes and preserve the antifungal armamentarium. Many other classes of pharmaceuticals typically seen
as non-antifungal do in fact have significant antifungal activity. Prominent among these are calcineurin inhibitors, antiarrhythmics,
antidepressants, antibacterials, and others. Some have activity alone and some augment the activity of conventional antifungals.
Unfortunately, clinical data are lacking for most of these agents and their role in therapy remains undefined. This review
focuses on several representative non-antifungal agents with antifungal activity. 相似文献
120.
Harnessing parallelism in multicore clusters with the All-Pairs,Wavefront, and Makeflow abstractions
Li Yu Christopher Moretti Andrew Thrasher Scott Emrich Kenneth Judd Douglas Thain 《Cluster computing》2010,13(3):243-256
Both distributed systems and multicore systems are difficult programming environments. Although the expert programmer may
be able to carefully tune these systems to achieve high performance, the non-expert may struggle. We argue that high level
abstractions are an effective way of making parallel computing accessible to the non-expert. An abstraction is a regularly
structured framework into which a user may plug in simple sequential programs to create very large parallel programs. By virtue
of a regular structure and declarative specification, abstractions may be materialized on distributed, multicore, and distributed
multicore systems with robust performance across a wide range of problem sizes. In previous work, we presented the All-Pairs
abstraction for computing on distributed systems of single CPUs. In this paper, we extend All-Pairs to multicore systems,
and introduce the Wavefront and Makeflow abstractions, which represent a number of problems in economics and bioinformatics.
We demonstrate good scaling of both abstractions up to 32 cores on one machine and hundreds of cores in a distributed system. 相似文献