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991.
992.
Dipping vats were used routinely in the southeastern U.S. in the early 1900s to eradicate the cattle fever tick. The legacy is many dip vat sites with arsenic (As)-contaminated soil and ground water. Assessing the extent of these As plumes can be time consuming and expensive. We describe a quicker and less expensive, onsite test for soil As. It is a modification of a commercially available test designed for As in water, taking about 10?min to complete, allowing large plume areas to be delineated in a single day. An As contaminant plume in Alachua County, FL, was delineated using the quick test. Soil samples taken from a large grid encompassing the plume were analyzed in the laboratory for As to confirm the results obtained with the quick test. The comparison showed that the quick test very accurately delineated the outer boundary of the plume as well as zones of higher As concentration within the plume. 相似文献
993.
OBJECTIVE--To compare the burden on relatives and outcome of people treated for severe acute psychiatric illness by a community service and a traditional hospital based service. DESIGN--Follow up of patients aged 16-65 who required admission to hospital or home treatment for psychiatric illness during January 1990 to February 1991. SETTING--Two Birmingham electoral wards, Sparkbrook and Small Heath; Sparkbrook has a community based service and Small Heath a traditional hospital based service. SUBJECTS--69 patients from Sparkbrook and 55 from Small Health. MAIN OUTCOME MEASURES--Scores on present state examination, social behaviour assessment schedule, and general health questionnaire. RESULTS--24 (35%) of Sparkbrook patients received some treatment in hospital during the initial episodes. Relatives of Sparkbrook patients were less distressed by their burden at the initial assessment than relatives of Small Health patients (mean score 0.11 v 0.29, p < 0.01). Relatives were also more satisfied with the support they received and the treatment received by patients. More patients from Sparkbrook than Small Health were in contact with a psychiatrist (81% (95% confidence interval 71% to 91%) v 62% (44% to 68%)) and community nurse (56% (44% to 68%) v 14% (13% to 24%)) one year after the initial episode. Sparkbrook patients spent significantly fewer days in hospital during the initial episode (8 days v 59 days) and the first year (20.6 v 67.9 days). CONCLUSION--The community based service is as effective as the hospital based service and is preferred by relatives. It is more effective in keeping people in long term contact with psychiatrists. 相似文献
994.
995.
A radioimmunoassay procedure was developed for the measurement of dehydroepiandrosterone (DHA) in peripheral serum in nonpregnant mares. The synthesis and conjugation of 3beta-hydroxy-5-androsten-19-al-17-one 19(0-carboxymethyl) oxime is described. Antisera were developed against this antigen and characterized. The most specific antiserum was used to measure DHA. Concentrations of DHA were greatest immediately before ovulation. 相似文献
996.
1. Previous investigations of the ecological genetics among amphipods in south-western U.S.A. suggested a xeric landscape promoted genetic divergence among passively dispersed freshwater invertebrates, thereby enhancing speciation events. We predicted that less divergence would occur among amphipod populations across similar geographic distances in mesic regions. 2. Eight Hyalella azteca populations were sampled along a 200-km transect in western Oregon, U.S.A. Genetic distances among populations were estimated from randomly amplified polymorphic DNA (RAPD). Genetic analyses indicated much less divergence among Oregon populations than among Arizona populations in an arid environment. 3. Behavioural observations support the genetic data: Oregon populations exhibit little differentiation in swimming behaviour, whereas Hyalella populations in Arizona exhibit extremes in swimming behaviour. 4. These results provide preliminary support for the hypothesis that a xeric landscape promotes genetic and behavioural divergence among amphipods. Many aquatic invertebrates classified as panmictic populations may encompass genetically distinct groups; those isolated by a xeric landscape are especially prone to diversification. 相似文献
997.
998.
Dean J. Kereiakes James L. Naughton Bruce Brundage Nelson B. Schiller 《The Western journal of medicine》1984,140(4):583-593
Since the introduction of insulin, heart disease has become a major impediment to survival in persons with diabetes mellitus. Coronary disease has increased severity and accelerated development in diabetic persons compared with an age- and sex-matched nondiabetic population. A peculiar vulnerability of women to the influence of diabetes with loss of premenopausal coronary disease protection has been found. The symptomatology of coronary events may differ and coronary care data show a higher incidence of sudden death in diabetic patients who have a myocardial infarction than in their non-diabetic counterparts. Insulin may play a role in the myocardial adjustment to an ischemic insult by enhancing glucose intake and suppressing lipolysis and ketogenesis. Carbohydrate intolerance in dogs, rhesus monkeys and humans appears associated with similar histologic and compositional changes in the myocardium. Abnormalities in diastolic ventricular function not attributable to large- or small-vessel coronary disease have been found in the diabetic subjects of each species. Studies in humans who have diabetes have assessed single pressure-volume relationships and more exacting measures of ventricular compliance are needed. Abnormalities of myocardial function in patients with diabetes have been found using echo and radionuclide techniques. Many of these findings need to be correlated with invasive data or confirmed in larger populations. Autonomic dysfunction is common in diabetic persons and may imply an associated poor prognosis. Reflex abnormalities in parasympathetic function are most prevalent and occur before sympathetic dysfunction. 相似文献
999.
The Cre/loxP system is a powerful tool for generating conditional genomic recombination and is often used to examine the mechanistic role of specific genes in tumorigenesis. However, Cre toxicity due to its non-specific endonuclease activity has been a concern. Here, we report that tamoxifen-mediated Cre activation in vivo induced the regression of primary lymphomas in p53−/− mice. Our findings illustrate that Cre activation alone can induce the regression of established tumors. 相似文献
1000.
Dean Vik Maria Consuelo Gazitúa Christine L. Sun Ahmed A. Zayed Montserrat Aldunate Margaret R. Mulholland Osvaldo Ulloa Matthew B. Sullivan 《Environmental microbiology》2021,23(6):2858-2874
Oxygen minimum zones (OMZs) are critical to marine nitrogen cycling and global climate change. While OMZ microbial communities are relatively well-studied, little is known about their viruses. Here, we assess the viral community ecology of 22 deeply sequenced viral metagenomes along a gradient of oxygenated to anoxic waters (<0.02 μmol/l O2) in the Eastern Tropical South Pacific (ETSP) OMZ. We identified 46 127 viral populations (≥5 kb), which augments the known viruses from ETSP by 10-fold. Viral communities clustered into six groups that correspond to oceanographic features. Oxygen concentration was the predominant environmental feature driving viral community structure. Alpha and beta diversity of viral communities in the anoxic zone were lower than in surface waters, which parallels the low microbial diversity seen in other studies. ETSP viruses were largely endemic, with the majority of shared viruses (87%) also present in other OMZ samples. We detected 543 putative viral-encoded auxiliary metabolic genes (AMGs), of which some have a distribution that reflects physico-chemical characteristics across depth. Together these findings provide an ecological baseline for viral community structure, drivers and population variability in OMZs that will help future studies assess the role of viruses in these climate-critical environments. 相似文献