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排序方式: 共有252条查询结果,搜索用时 15 毫秒
41.
42.
Ellen B Wiedner Charlie Gray Peter Rich Gary L Jacobson Ramiro Isaza Dennis Schmitt William A Lindsay 《Journal of zoo and wildlife medicine》2008,39(2):248-251
Umbilical hernias were diagnosed in two captive-born, female Asian elephant (Elephas maximus) calves several weeks after birth. Daily manual reduction of the hernias for 5 wk in the first case and for 5 mo in the second resulted in complete closure of the defects. Nonsurgical repair of uncomplicated, fully reducible umbilical hernias in Asian elephants can be an alternative to surgery. 相似文献
43.
Multidrug-resistant (MDR) bacteria are an emerging threat in human and veterinary medicine. There are few reports about infections caused by MDR isolates in horses. The aim of this study was to provide an overview of infections caused by MDR bacteria at the Equine Hospital Zurich between 2012 and 2015. Medical records were searched for horses with confirmed MDR bacterial infection. Multidrug resistance was defined according to human guidelines specific for each pathogen. MDR isolates were most commonly isolated from post-procedural infections (53/110, 48%), followed by musculoskeletal (16/110, 15%) and soft tissue infections (16/110, 15%). Escherichia coli (32/158, 20%) and Staphylococcus aureus (25/158, 16%) were the most common isolates. High resistance rates precluded therapy with commonly used antimicrobial drugs. The overall mortality rate was 20% (22/108) but depended on the localisation of the infection. Antimicrobial treatment prior to development of infection was reported for 89% (91/102) of horses. This study showed that MDR pathogens, mainly MDR E. coli and MRSA, cause a considerable number of infections in horses. A wide range of infections was seen, however, nosocomial infections predominated. These cases are typically hospitalised, pretreated with antibiotics, and suffering from comorbidities putting them at high-risk for acquiring infections caused by MDR isolates. The mortality of such infections was generally low but depended on site of infection. 相似文献
44.
Miller R Kaneene JB Schmitt SM Lusch DP Fitzgerald SD 《Preventive veterinary medicine》2007,82(1-2):111-122
The wild white-tailed deer (Odocoileus virginianus) population in Michigan, USA, has endemic Mycobacterium bovis. We determined whether there were spatial clusters of retrospective TB cases in white-tailed deer in northeastern Michigan and identified specific factors associated with the spatial clusters. Data from hunter-harvested deer (age, gender, TB status, and geographic section) were collected by the Michigan Department of Natural Resources (MDNR) during TB surveillance from 1995 to 2002. Land cover (vegetation, land-use) and land type (soil types and drainage characteristics, landforms) described potential deer habitats. Specific locations of large-scale supplemental feeding sites were collected from the MDNR aerial surveillance program from 1997 to 2002. Analyses were conducted using principal components derived from environmental data (and other risk factors) on spatial clusters of disease (identified by the spatial scan statistic). Spatial effects were incorporated into the multivariable analyses by using a neighborhood approach. A total of 420 deer with M. bovis infection were identified from 1995 to 2002, out of 39,451 harvested deer from 3216 TRS units, and spatial clusters of cases were identified. A total of seven principal components of environmental data were generated. Clusters were associated with the presence of large expanses of deciduous forests on moraine ridges separated by low areas of forested wetlands, and the presence of many small lakes. Factors that promoted congregation of deer for extended periods of time (natural cover, access to water, and less human contact) appeared to be associated with increased odds of TB positivity. This suggests that there are specific areas where interventions can be implemented to reduce congregation of animals and disrupt the cycle of infection transmission. 相似文献
45.
Melanie Schmitt Andreas Turberg Michael Londershausen August Dorn 《Pest management science》1996,48(4):375-388
The calcium channel and the ‘calcium release channel’ of muscle membrane of the cockroach Periplaneta americana have been characterized. Biological assays with calcium channel blockers and ryanodine on different insects and acari revealed pronounced insecticidal effects with ryanodine, but not with calcium channel blockers, at concentrations between 0·1 and 300 μg ml−1. Skeletal muscle membranes derived either from the tubular network or from the sarcoplasmatic reticulum of P. americana were characterized with respect to the binding of the dihydropyridine (DHP) [3H]isradipine (PN 200-110), the phenyl-alkylamine [3H]verapamil and the alkaloid [3H]ryanodine. Preliminary binding studies with the benzothiazepine [3H]diltiazem suggest a low-affinity binding site with a IC50 value of 3·3 μM . All binding sites tested were sensitive to treatment with proteinase K. Optimal conditions for binding of the radioligand ryanodine revealed the highest specific binding at pH 8 and at calcium chloride concentrations between 100 and 500 μM . EGTA at 10 μM abolished 95% of the ryanodine binding. Binding studies with calcium channel binding sites revealed a pronounced effect of low Ca2+ concentrations on specific isradipine binding, whereas verapamil and diltiazem binding were only reduced by the presence of 200 μM EGTA. With respect to high Ca2+ concentrations, specific binding of diltiazem, isradipine and verapamil was reduced by 73, 40 and 20%, respectively, at 5 mM Ca2+. Radioligand binding experiments showed high-affinity binding sites for ryanodine and isradipine. KD values of 0·95 nM (Bmax=550 fmol mg−1 protein) and 0·75 nM (Bmax=213 fmol mg−1 protein) were determined respectively. A lower-affinity binding site was identified in binding studies with verapamil (KD=7·4 nM and Bmax=27 fmol mg−1 protein). [3H]isradipine displacement studies with several dihydropyridines revealed the following ranking of affinity: nitrendipine>isradipine>Bay K8664≪nicardipine. Displacement of [3H]verapamil binding by effectors of the phenylalkylamine binding site showed that bepridil and S(-)verapamil had the highest affinities of the compounds tested followed by (±)verapamil, nor-methylverapamil and R(+)verapamil. 相似文献
46.
Pearl grafting: Tracking the biological origin of nuclei by straightforward immunological methods
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Nelly Schmitt Frédéric Marin Jérôme Thomas Laurent Plasseraud Marina Demoy‐Schneider 《Aquaculture Research》2018,49(2):692-700
French Polynesia is renowned for the production of Tahitian black pearl. These gems are obtained by grafting a nucleus into the gonad of a receiving oyster together with a graft, i.e. a small section of mantle tissue of a donor oyster. This procedure initiates the formation of a pearl sack around the nucleus, and subsequently, the deposition of concentric layers of nacre. The nucleus plays a key‐role in pearl formation and its characteristics influence markedly the quality of the final product. As it is manufactured from mollusc shells, it contains a small percentage of organics. In the present paper, we used a set of biochemical techniques to characterize and compare the organic matrices from two types of nuclei that are currently used in French Polynesia: that from the freshwater mussel Amblema sp., and that from the pearl oyster Pinctada sp. To this end, we extracted the matrices from nuclei and performed FT‐IR, monodimensional electrophoresis, and enzyme‐linked immuno‐sorbent assay (ELISA). Our data show that the matrix associated with Amblema nuclei has a very different biochemical signature from that of Pinctada nuclei, a fact that may explain the improved tolerance of grafted oysters to nuclei of Pinctada origin. In the absence of complex physical methods of investigation, simple immunological techniques and FT‐IR performed on the extracted organic matrix are extremely reliable and effective for discriminating nuclei from these two sources. We assert that such techniques can be used as a diagnostic test to track unambiguously the biological origin of nuclei to avoid fraud. 相似文献
47.
I. V. Yevdokimov A. A. Larionova M. Schmitt V. O. Lopes de Gerenyu M. Bahn 《Eurasian Soil Science》2010,43(12):1373-1381
The contributions of root and microbial respiration to the total emission of CO2 from the surface of gray forest and soddy-podzolic soils were compared under laboratory and field conditions for the purpose
of optimizing the field version of the substrate-induced respiration method. The magnification coefficients of respiration
upon the addition of saccharose (k
mic) were first determined under conditions maximally similar to the natural conditions. For this purpose, soil cleared from
roots was put into nylon nets with a mesh size of 40 μm to prevent the penetration of roots into the nets. The nets with soil
were left in the field for 7–10 days for the compaction of soil and the stabilization of microbial activity under natural
conditions. Then, the values of k
mic were determined in the root-free soil under field conditions or in the laboratory at the same temperature and water content.
The contribution of root respiration as determined by the laboratory version of the substrate-induced respiration method (7–36%)
was lower compared to two field versions of the method (27–60%). Root respiration varied in the range of 24–60% of the total
CO2 emission from the soil surface in meadow ecosystems and in the range of 7–56% in forest ecosystems depending on the method
and soil type. 相似文献
48.
49.
D Bencharif L Amirat O Pascal M Anton E Schmitt S Desherces G Delhomme M‐L Langlois P Barrière M Larrat D Tainturier 《Reproduction in domestic animals》2010,45(2):189-200
Twenty sperm samples from five dogs were frozen in liquid nitrogen at ?196°C in 16 different media, two control media containing 20% egg yolk and 6% low‐density lipoproteins (LDL); 10 test media containing 6% LDL (the active cryoprotective ingredient of chicken egg yolk) combined with 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100 mmol of glutamine respectively at 4%, 5%, 7%, and 8% LDL. Following thawing, sperm mobility was assessed using an image analyser, HAMILTON THORN CERROS 12. The percentage of mobile spermatozoa was 62.05% in the 6% LDL + 20 mmol glutamine medium compared with 48.90% in the egg yolk‐based medium (p < 0.05) or 57.55% for the 6% LDL medium (p < 0.05). Furthermore, in most cases, the motility parameters (average path velocity, curvilinear velocity, straight line velocity) in the 6% LDL + 20 mmol glutamine medium, were superior, to a statistically significant extent, to those in the control media. Finally, the 6% LDL + 20 mmol glutamine combination provides spermatozoa with better protection during freezing than egg yolk or the 6% LDL medium alone in terms of acrosome integrity (fluorescein isothiocyanate–Pisum sativum agglutinin test: p < 0.05), the flagellar plasma membrane (hypo‐osmotic test: p < 0.05 for 6% LDL), the DNA (acridine orange test; no significant difference) and the integrity of the acrosome (Spermac® test: no significant difference). 相似文献
50.
Surveillance and control activities for bovine tuberculosis (bTB) in free-ranging Michigan white-tailed deer (Odocoileus virginianus) have now been underway for over a decade. Significant progress has been made, lowering apparent prevalence in deer in the core area by >60%, primarily via reduction of deer densities through hunting, and restrictions on public feeding and baiting of deer. These broad strategies of the Michigan Department of Natural Resources (MDNR), implemented with the cooperation of Michigan deer hunters, halved the deer population in the bTB endemic area. However, as hunters see fewer deer, their willingness to sustain aggressive harvests has waned, and public resentment of control measures has grown. During the past four years, apparent prevalence in core area deer has held approximately steady just below 2%. After bottoming out in 2004 at an estimated 10-12 deer/km(2), deer numbers have since rebounded by ~ 30%. Public compliance with baiting and feeding restrictions has been variable. In general, hunters in the core area do not perceive bTB as a problem, in spite of 13 years of MDNR outreach. To date, MDNR has expended more than US$23 million on TB-related activities. Of late, a substantial portion of that funding has been diverted to support other programs which have suffered from budget shortfalls. Livestock herd breakdowns continue to occur sporadically, averaging 3-4 per year 2005 to present. In total, 46 cattle and 4 captive deer herds have been diagnosed bTB positive statewide, the majority yielding only 1 positive animal. Five cattle herds were twice infected, one thrice. Michigan Department of Agriculture (MDA) policy emphasis has shifted towards obtaining producer support for wildlife risk mitigation and farm biosecurity. Funding has proven a limiting factor, with the majority of the US$63 million spent to date devoted to whole herd testing. Nevertheless, some initiatives justify cautious optimism. Promising research to support eventual vaccination of wild deer continues. Some hunters and landowners have begun to recognize the costs of high deer densities and supplemental feeding. A peninsula-wide ban on baiting and feeding was enacted. Some cattle producers, recognizing their precarious circumstances, have begun work to change long-held prevailing opinions among their peers about farm biosecurity. Yet formidable challenges remain, and evidence suggests that eradication of bTB, if it can be achieved, will take decades, and will require greater public and political resolve than has been demonstrated thus far. 相似文献