Photonic crystal light collectors in fish retina improve vision in turbid water     

Kreysing M  Pusch R  Haverkate D  Landsberger M  Engelmann J  Ruiter J  Mora-Ferrer C  Ulbricht E  Grosche J  Franze K  Streif S  Schumacher S  Makarov F  Kacza J  Guck J  Wolburg H  Bowmaker JK  von der Emde G  Schuster S  Wagner HJ  Reichenbach A  Francke M 《Science (New York, N.Y.)》2012,336(6089):1700-1703

Despite their diversity, vertebrate retinae are specialized to maximize either photon catch or visual acuity. Here, we describe a functional type that is optimized for neither purpose. In the retina of the elephantnose fish (Gnathonemus petersii), cone photoreceptors are grouped together within reflecting, photonic crystal-lined cups acting as macroreceptors, but rod photoreceptors are positioned behind these reflectors. This unusual arrangement matches rod and cone sensitivity for detecting color-mixed stimuli, whereas the photoreceptor grouping renders the fish insensitive to spatial noise; together, this enables more reliable flight reactions in the fish's dim and turbid habitat as compared with fish lacking this retinal specialization.  相似文献   

Genetic data from avian influenza and avian paramyxoviruses generated by the European network of excellence (EPIZONE) between 2006 and 2011--review and recommendations for surveillance     

Dundon WG  Heidari A  Fusaro A  Monne I  Beato MS  Cattoli G  Koch G  Starick E  Brown IH  Aldous EW  Briand FX  Le Gall-Reculé G  Jestin V  Jørgensen PH  Berg M  Zohari S  Metreveli G  Munir M  Ståhl K  Albina E  Hammoumi S  Gil P  de Almeida RS  Smietanka K  Domańska-Blicharz K  Minta Z  Van Borm S  van den Berg T  Martin AM  Barbieri I  Capua I;EPIZONE Network of Excellence Molecular Epidemiology of AI;APMV working group 《Veterinary microbiology》2012,154(3-4):209-221

Since 2006, the members of the molecular epidemiological working group of the European "EPIZONE" network of excellence have been generating sequence data on avian influenza and avian paramyxoviruses from both European and African sources in an attempt to more fully understand the circulation and impact of these viruses. This review presents a timely update on the epidemiological situation of these viruses based on sequence data generated during the lifetime of this project in addition to data produced by other groups during the same period. Based on this information and putting it all into a European context, recommendations for continued surveillance of these important viruses within Europe are presented.  相似文献   

Comparison of Hb‐200 and 6% hetastarch 450/0.7 during initial fluid resuscitation of 20 dogs with gastric dilatation‐volvulus     

Carol E. Haak DVM  Elke Rudloff DVM  DACVECC  Rebecca Kirby DVM  DACVIM  DACVECC 《Journal of Veterinary Emergency and Critical Care》2012,22(2):201-210

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Laboratory diagnosis of avian influenza by reverse transcription (RT)-PCR     

Starick E  Werner O  Kaden V 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(7-8):290-295

RT-PCR assays which amplify conserved regions of the influenza A virus gene are useful tools for the rapid and specific detection of infections of poultry with avian influenza virus (AIV) and for the investigation of large numbers of samples, e.g. within the framework of surveillance programs. Here, we present findings on the efficiency and on the limits of an RT-PCR assay which amplifies a part of the matrix protein gene. Sensitivity and specificity of the method were increased by the additional use of nested PCR. Parameters which may have an essential influence on the detection limit are outlined and discussed. A major focus of the study is the detection of AIV RNA from organ samples and swabs.  相似文献   

Analysing land-cover changes in relation to environmental variables in Hesse,Germany   总被引：14，自引：7，他引：14  

Hietel  Elke  Waldhardt  Rainer  Otte  Annette 《Landscape Ecology》2004,19(5):473-489

Land-use and land-cover changes affect ecological landscape functions and processes. Hence, landscape ecologists have a central interest in a comprehensive understanding of such changes. Our study focuses on the relationships between environmental conditions and agricultural land-cover changes. We present a method to (i) characterise the major spatial-temporal processes of land-cover changes, (ii) identify the correlations between environmental attributes and land-cover changes and (iii) derive potential environmental drivers of land-cover changes in a German marginal rural landscape. The method was applied to study land-cover dynamics from 1945 to 1998 in the districts of Erda, Steinbrücken and Eibelshausen, situated in the marginal rural landscape of the Lahn-Dill Highlands, Germany. We employed land-cover data gained by the interpretation of multi-temporal aerial photographs. Various environmental variables were introduced into the analyses. We identified physical landscape attributes (elevation, slope, aspect, available water capacity and soil texture) and structural landscape dimensions (patch size, patch shape and distance between patch and nearest settlement). With the aid of GIS, K-means partitioning and canonical correspondence analysis, we investigated land-cover trajectory types, land-cover transitions at individual time intervals and their relationships to these environmental variables. Our results show that, between 1945 and 1998, land-cover changes correlated with the physical attributes of the underlying landscape. On the other hand, the structural landscape dimensions correlated with land cover only in periods of minor land-cover changes (1972–98). Greater diversity of physical landscape attributes is correlated with greater land-cover dynamics. Besides the important influence of socio-economic factors, land-cover changes in the study areas took place within the relatively stable physical constraints of the underlying landscape.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   

Fluid resuscitation and the trauma patient.     

Elke Rudloff  Rebecca Kirby 《Veterinary Clinics of North America: Small Animal Practice》2008,38(3):645-52, xiii

Traumatic shock can result from one or more of the following: hypovolemia, increased capillary permeability and vasodilatation, impaired myocardial contractility or dysfunction, blood loss, and cardiovascular obstruction. Animals with traumatic injuries are less tolerant of sudden increases in hydrostatic pressure, which can exacerbate fluid leakage into damaged tissues and disrupt blood clots. Pain amplifies the shock response, and analgesic therapy is always recommended in the trauma patient. Therapy must be individualized and monitored closely.  相似文献   

Pathology and mass mortality of Pacific oysters, Crassostrea gigas (Thunberg), in 2005 at the East Frisian coast, Germany   总被引：1，自引：0，他引：1  

Watermann BT  Herlyn M  Daehne B  Bergmann S  Meemken M  Kolodzey H 《Journal of fish diseases》2008,31(8):621-630

In 2005, Pacific oysters, Crassostrea gigas , were collected from May to September along the East Frisian coast and processed for histology. Because of mass mortalities in September, additional samples of moribund oysters and apparently healthy blue mussels, Mytilus edulis , were subjected to virological and ultrastructural investigation. The oysters displayed a variety of pathological conditions including viral gametocytic hypertrophy which is reported here for the first time from the German coast. Haemocyte aggregations in the digestive tract, in the intestinal mucosa and submucosa, in the mid-gut gland and in the ventricle of the heart were commonly observed at some stations. In association with mass mortalities, severe gill necrosis occurred which may have contributed to the high mortality rates. Total mortality rates of up to approximately 60% were seen. All size classes and thus age classes of oysters were affected, with highest mortality rates within the youngest age classes which had just reached sexual maturity (shell lengths <40 mm). The smallest dead oysters had shell lengths of 10 mm. The phenomenon was mainly restricted to C. gigas stocks in harbours, probably because of favourable conditions for infection, i.e. limited water exchange, less food availability, reduced oxygen content and higher pollution levels.  相似文献   

Transendoscopic injection of poly-L-lactic acid into the soft palate in horses: A new therapy for dorsal displacement of the soft palate?     

Anja Cehak Dr Med Vet  Eckehard Deegen Prof Dr Dr Med Vet  Wolfgang Drommer Prof Dr Dr Med Vet  Elke Lütkefels Dr Med Vet  Bernhard Ohnesorge PD Dr Med Vet Dipl ECEIM 《Journal of Equine Veterinary Science》2006,26(2):59-66

The purpose of this study was to establish a minimal invasive, transendoscopic technique for injection of poly-L-lactic acid into the free edge of the soft palate that can be performed on the standing sedated horse. Furthermore, whether the implant material induces an increase in fibrous tissue at the injection site, resulting in a greater rigidity of the soft palate, was determined.In 4 horses, the injection was performed bilaterally along the caudal margin of the soft palate, and the influence of the treatment on the soft palate function was determined. Clinical, radiographic and endoscopic examinations at rest were performed before and up to 168 days after injection according to a standardized examination protocol.In 6 horses, the implant material was injected unilaterally into the right half of the caudal margin of the soft palate. After clinical and endoscopic follow-up examinations, 2 horses each were killed 28, 84, and 168 days after the implantation procedure. At necropsy, macroscopic comparison of the treated and the untreated halves of the soft palate showed the influence on the size of the ostium intrapharyngeum and on the soft palate thickness. The localization of the implant material in the soft palate and the tissue response to the poly-L-lactic acid were evaluated histologically.Transendoscopic injection into the soft palate requires neither general anesthesia nor wound management, and it is noted for minimal tissue trauma. After injection, no alteration of the soft palate function was observed in horses with normal upper airway mechanics. One horse with intermittent dorsal displacement of the soft palate showed an improvement of the soft palate function for 112 days after implantation. No significant alteration in the size of the ostium intrapharyngeum was evident in any horse. Histologic assessment indicated the presence of implant material during the entire observation period of 168 days. The implant was accompanied by a granulomatous inflammation, and it was encapsulated by fibrous tissue. This may result in an increase in stiffness, and subsequent a greater rigidity of the soft palate, preventing it from displacement. The injection may therefore be considered an alternative to established therapies in horses showing dorsal displacement of the soft palate because of its unstable free edge.  相似文献   

Differential diagnosis of movement disorderd in pullets. 1. Clinical and pathomorphological studies of pullets following spontaneous outbreak of avian encephalomyelitis (AE)     

V Bergmann 《Monatshefte für Veterin?rmedizin》1972,27(6):231-237

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Histological and electron microscopy studies on the adenocarcinomatosis of laying hens]     

G Ilchmann  V Bergmann 《Archiv fuer experimentelle veterinaermedizin》1975,29(6):897-907

Histological examination of 187 tumours from 98 hens (laying hybrids of various lines, age 80-123 weeks) showed that highly-differentiated tubulo-alveolar adenocarcinoma was present in 95% of the birds; in 20% it had a scirrhus structure. Histological and ultrastructural features of these carcinomas and their tendency to form secretory granules pointed to an origin from the protein-secreting part of the oviduct (magnum). In the remaining 5% of birds there were non-specific adenocarcinomas (probably ovarian carcinoma) and mesotheliomas.  相似文献