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SETTING: Three commercial deer herds, each containing more than 500 deer, experienced outbreaks of tuberculosis (TB) ranging from a 6% prevalence to disease levels >50%. Intensive diagnostic testing was carried out over short time intervals after the initial diagnosis of TB. OBJECTIVE: To eradicate M. bovis infection from herds of farmed red deer (Cervus elaphus) in New Zealand, which had significant outbreaks of tuberculosis (>5%), using complementary diagnostic tests and elective slaughter of all test positive animals. DESIGN: Whole herd mid cervical skin tests (MCT) were used as the primary test and a comparative cervical test (CCT) as an ancillary test. In an attempt to enhance TB eradication, ancillary blood tests comprising; lymphocyte transformation tests (LT) and enzyme-linked immunosorbent assays (ELISA) were used in parallel with MCT, or as serial tests, to complement skin testing. RESULTS: One deer herd (N), which had an acute outbreak (6%) of TB in adult stock, responded quickly to testing and the disease was eradicated within 12 months. A second more chronically infected herd (B), with low prevalence (2%) of TB initially in pregnant hinds which were retained over the breeding cycle, developed widespread uncontrollable spread of infection, that could not be contained by exhaustive testing. The final herd (S), which had an acute outbreak of TB at a prevalence >90% in young fawns, responded well to testing and became TB-free within 1 year. CONCLUSIONS: TB can be eradicated from infected farmed deer herds, using currently available TB tests, irrespective of disease prevalence. The caveat is that disease must be diagnosed early in the acute phase of infection. Undiagnosed infection over winter in breeding hinds in one herd produced a refractory infection in adult males and females and uncontrollable spread to newborn fawns. Disease could not be eradicated using comprehensive diagnostic schedules. A widespread but controllable outbreak of acute TB in another herd, appeared to have caused sufficient selective pressure on adult stock that genetically resistant adults were selected within a very short time frame (<1 year).  相似文献   
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BackgroundPressure injuries have a major impact on patients and healthcare organisations. The complications of pressure injuries increase morbidity and mortality rates and are costly to individuals and healthcare systems. The total prevalence rate of pressure injuries within acute care hospitals in Australia and New Zealand is unknown, and despite a focus on prevention, pressure injuries still occur within these hospital settings.AimTo report the prevalence of pressure injuries within acute care settings in Australian and New Zealand hospitals and to identify the stage and location of pressure injuries and analyse the methods used to conduct pressure injury point prevalence studies.MethodsA systematic review of studies published in CINAHL, MEDLINE and Cochrane databases and a two-part grey literature search, including a customised Google search and a targeted website search, was undertaken up to July 2019. The systematic review was prospectively registered with PROSPERO (CRD42018105566).FindingsThe overall prevalence of pressure injuries in acute-care hospitals in Australia and New Zealand is 12.9% (95% CI, 9.5%–16.8%) and the hospital-acquired pressure injury prevalence is 7.9% (95% CI, 5.7%–10.3%). Stage I and stage II are the most common pressure injuries. The most frequent locations for pressure injuries are the sacrum/buttock/coccyx area (41%) and the heels (31%). The reporting of details about methodology varies considerably between studies.DiscussionPressure injuries remain a significant problem within acute-care hospital settings. Total prevalence rates are decreasing over time with the numbers of stage I and II pressure injuries decreasing faster than other pressure injuries.ConclusionThe findings from this study can be used to set performance benchmarks within acute-care hospitals in Australia and New Zealand. Pressure injuries are preventable and pressure injury prevalence studies can be used to monitor the effectiveness of nursing care processes to improve patient outcomes.  相似文献   
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The use of prothrombin complex concentrates (PCCs), a heterogeneous combination of coagulation factors and counterbalancing inhibitor components, has broadened in recent years beyond single‐factor replacement in conditions such as hemophilia B, to encompass emergency reversal of anticoagulation secondary to oral vitamin K antagonists, ie, warfarin therapy. PCCs also have been studied in other bleeding disorders, such as surgery‐related and trauma‐related bleeding. This review provides an updated examination of the differences among PCC formulations, their potential role in the management of bleeding disorders, and the primary safety issues affecting their use. Am. J. Hematol. 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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It is both challenging and desirable to have drug sensitizers released at acidic tumor pH for photodynamic therapy in cancer treatment. A pH-responsive carrier was prepared, in which fumed silica-attached 5,10,15,20-tetrakis(4-trimethylammoniophenyl)porphyrin (TTMAPP) was encapsulated into 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) nanocomposite liposomes. The sizes of agglomerates were determined by dynamic light scattering to be 115 nm for silica and 295 nm for silica-TTMAPP-DOPC liposomes. Morphological changes were also found in TEM images, showing liposome formation at pH 8.5 but collapse upon silanol protonation. TTMAPP release is enhanced from 13% at pH 7.5 to 80% at pH 2.3, as determined spectrophotometrically through dialysis membranes. Fluorescence emission of TTMAPP encapsulated in the dry film of liposomes was reduced to half at pH 8.6 when compared to that at pH 5.4, while the production of singlet oxygen was quintupled at pH 5.0 compared to pH 7.6. Upon treatment of human prostate cancer cells with liposomes containing 6.7 μM, 13 μM, 17 μM and 20 μM TTMAPP, the cell viabilities were determined to be 60%, 18%, 20% and 5% at pH 5.4; 58%, 30%, 25% and 10% at pH 6.3; and 90%, 82%, 68% and 35% at pH 7.4, respectively. Light-induced apoptosis in cancerous cells was only observed in the presence of liposomes at pH 6.3 and pH 5.4 but not at pH 7.4, as indicated by chromatin condensation.

Nanocomposite liposomes are relatively stable in weak basic solutions but effectively release porphyrins at acidic pH, as indicated by the difference in fluorescence.  相似文献   
69.
It is well established that calcium oxalate stones may be caused by colonic or ileum oxalate (Ox) hyperabsorption (secondary to intestinal dysfunction). Studies have reported that increased intestinal permeability (IP) can cause hyperabsorption of nutrients culminating in passive diffusion of Ox. In South Africa, renal stones occur in the white population (W) but are extremely rare in the black population (B). Previous studies have shown that despite B having a hyperoxalurogenic diet relative to W, urinary Ox in the former is not higher. It has been suggested that different Ox handling mechanisms in the groups are the cause of this disparity. The present study was undertaken to examine whether the IP index, a reliable and accurate measure of intestinal integrity, plays a role in this anomaly. Ten healthy males from each group ingested a dual-sugar isotonic solution containing 5 g lactulose (LA) and 2 g mannitol (MA). IP was assessed by comparing the LA:MA ratio in 5 h urine samples using high performance anion exchange chromatography coupled with pulse amperometric detection to measure the concentration of each sugar. 24 h dietary intake and urine composition were also determined. LA excretion was identical in both groups (0.03 %) while MA excretion was 8.3 % in B and 11.3 % in W. IP index was 0.004 for B and 0.003 for W. It is concluded that IP is not a contributory factor in the apparent different handling of dietary Ox in B and W South Africans. It is speculated that differences in renal transporters may play a role.  相似文献   
70.
Body piercing, which is prevalent in young adults, has been suggested to be associated with features usually related to posttraumatic stress disorder (PTSD) such as high‐risk behaviours and psychopathological symptoms and might be motivated by a wish to deal with prior traumatic experiences. However, to date, no research has investigated the relationship between this practice and PTSD symptoms. The present research aims to investigate the possible relationship between body piercing and PTSD symptoms in French‐speaking young adults. According to our results, having two or more body piercings was associated with a twofold increased risk for scoring above the cut‐off score for PTSD on the PTSD checklist. Our findings suggest that two or more body piercings might serve as an identifiable marker for PTSD symptoms and may have important implications for clinical screening. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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