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91.
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Footrot is a contagious disease of small ruminants which is caused by the bacterium Dichelobacter nodosus. In its virulent form there are severe economic losses and a very significant animal welfare issue. Sheep and goats can be vaccinated for treatment and prevention of the disease. There are 10 different serogroups of D. nodosus (A–I and M) and immunity is serogroup-specific. When all 10 serogroups are presented together in a vaccine, protection persists for only a few months due to “antigenic competition”. Consequently we evaluated the use of sequential monovalent or bivalent vaccines to control/eliminate/eradicate virulent footrot in a longitudinal intervention study on 12 commercial farms in southeast Australia with flock sizes of approximately 1200–4200 sheep. Overall, virulent footrot was eradicated from 4 of the flocks, 2 of which had 2 serogroups, and the others 4 or 5 serogroups. Where there were only 1 or 2 serogroups (3 farms) the clinical response was rapid and dramatic; prevalence was reduced from 45 to 50% before vaccination to 0% (2 farms) or 0.4% (1 farm) after one round of vaccination. In the remaining 9 flocks there were more than 2 serogroups and successive bivalent vaccines were administered leading to eradication of virulent footrot on 2 farms over 4 years and control of the disease on all but 3 of the others. Of the latter farms, 1 discontinued, and 2 initially had poor response to vaccine due to misdiagnosis of serogroup ‘M’, which was previously unknown in Australia. Control was achieved after administration of a serogroup M vaccine. These results provide clear evidence for control, elimination and eradication of virulent footrot by outbreak-specific vaccination in Australia.  相似文献   
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Plants belonging to the genus Opuntia spp. are the most abundant of the Cactaceae family, grown throughout America and the Mediterranean central area. Its fruit, known as cactus pear or prickly pear, is an oval berry grouped in different colors. Some studies have shown its antioxidant activities which may help in preventing chronic pathologies such as diabetes. The purpose of the study was to evaluate the antioxidant capacity of three varieties of prickly pear juice (red-purple, white-green and yellow-orange) in five different concentrations (100, 250, 500, 750, and 1000 mg/mL) by DPPH (1,1-diphenyl-2-picrylhydrazyl radical) colorimetric method, selecting the best variety to determine its anticlastogenic potential against methyl methanesulfonate (MMS). The results indicate that the highest antioxidant was found in the juice of the prickly pear red-purple variety (PPRP), in all concentrations. Its anticlastogenic potential was therefore evaluated with a micronucleus assay. The experiment was run over two weeks. A negative control was included along with a positive control with MMS (40 mg/kg), a group of mice treated with PPRP (25 mL/kg), and three groups with PPRP (in doses of 25, 16.5 and 8.3 mL/kg) plus the mutagen. The PPRP was administered daily by oral gavage and the MMS was injected intraperitoneally five days prior to the end of the experiment. Blood samples were obtained at 0, 24, 48, 72 and 96 h in order to determine the frequency of micronucleated polychromatic erythrocytes (MNPE). The results indicated that PPRP is not a genotoxic agent, on the contrary, it may reduce the number of MNPE. In this regard, the PPRP showed an anticlastogenic effect directly proportional to its concentrations. Thus, the highest protection was obtained with a concentration of 25 mL/kg after 48 h of treatment.  相似文献   
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An exciting new era has begun in the management of patients who either have survived or are at risk for lethal ventricular arrhythmias. Electrophysiologic testing, a remarkably safe procedure, can be used to guide selection of the best protective drug regimen. A new device, the automatic implantable cardioverter-defibrillator, continuously monitors the heart rate and converts sustained ventricular tachyarrhythmias to normal sinus rhythm. Drs Lehmann and Steinman anticipate a significant reduction of the death rate in these patients in the coming years.  相似文献   
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Abstract

This study examined differences in nurses' fear of death and level of comfort with patients having a poor prognosis for survival, as a function of the nurses' occupational level, work setting, and level of exposure to such patients. In addition, the relationship among the multidimensional aspects of fear of death and level of comfort with patients' poor prognosis was assessed. The sample included 312 professional and paraprofessional nurses who worked in hospitals and nursing homes. Level of comfort with working with dying patients was found to differ significantly by exposure to such patients and by occupational role. Fear of death for significant others was found to differ significantly by work setting. Finally, a significant inverse relationship was found between comfort working with dying patients and overall fear of death. Suggestions for future research are presented.  相似文献   
100.
Derouet H  Lehmann J  Stamm B  Lühl C  Römer D  Georg T  Isenberg E  Gebhardt T  Stoeckle M 《European urology》2002,41(2):144-53; discussion 153-4
OBJECTIVES: Age dependent secretion of testicular and adrenal androgens was examined in healthy men and patients with erectile dysfunction (ED). METHODS: In 95 healthy men (age 20-74 years) and 739 patients with ED, luteineizing hormone (LH, n = 739), adrenocorticotropic hormone (ACTH, n = 480) and the secretion products of testis and adrenal gland testosterone (T, n = 750), free testosterone (fT, n = 718), dehydroepiandrosteronesulfate (DHEAS, n = 598) and cortisol (n = 538) were measured. RESULTS: In healthy men, LH was measured from 0.75-8.58 mIU/ml and ACTH from 10.59-121.7 pg/ml. Statistically, age was not correlated to LH (P = 0.573) and ACTH (P = 0.833) in healthy men. The secretion products T (P < 0.05), fT (P < 0.001), DHEAS (P < 0.001) and cortisol (P < 0.05) declined significantly with age in healthy persons. In patients with ED, a significant age dependent increase of LH (P < 0.05, n = 739), but not ACTH (P = 0.469, n = 480) was found. T (P < 0.001, n = 736), fT (P < 0.001, n = 718) and DHEAS (P < 0.001, n = 598), but not cortisol (P = 0.307, n = 538) declined in age dependent patients with ED. Age matching revealed a statistical significant elevation (P < 0.05) only for LH (n = 659) in comparison to healthy men (n = 94), all other hormones were not different in both groups. CONCLUSION: An LH-increase in patients with erectile dysfunction underlines the importance of Leydig cell degeneration in this disease, but age dependent decline of T secretion was comparable to healthy men, demonstrating a working hypophyseal-testicular-axis. Indication of androgen replacement is therefore limited to selected cases.  相似文献   
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