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231.
E. Drijfhout M. J. Silbernagel D. W. Burke 《European journal of plant pathology / European Foundation for Plant Pathology》1978,84(1):13-26
Pathogenicity and symptom expression of seventeen described isolates of bean common mosaic virus (BCMV) and five previously unreported isolates were compared on many bean cultivars (Phaseolus vulgaris L.). From these cultivars, a standard set of differentials were assigned to nine groups with different disease reactions. The twenty-two virus isolates comprised seven strain (pathotype) groups, three of which were divided into two subgroups each. To promote international standardization in BCMV research, recommendations are given for test conditions and procedures, criteria for strain differentiation, and maintenance of differential cultivars and virus strains.Samenvatting Zeventien beschreven stammen van het bonerolmozaïekvirus en vijf niet geïdentificeerde isolaten (Tabel 1) werden bestudeerd op een uitgebreide reeks van toetsrassen. De meeste van deze toetsrassen waren in de literatuur als zodanig vermeld, maar door de desbetreffende onderzoekers waren vaak verschillende series toetsrassen gebruikt, hetgeen de onderlinge vergelijking van de stammen bemoeilijkte.De bedoeling van dit onderzoek was: vergelijking en indeling van de virusstammen, samenstelling van een standaard-toetsrassenserie en het ontwerpen en beschrijven van werden zowel in Wageningen als in Prosser, Washington, USA, uitgevoerd met dezelfde virusisolaten en dezelfde zaadmonsters van de toetsrassen.De toetsrassen konden op grond van hun differentiële reacties na inoculatie met de virusstammen worden ingedeeld in negen groepen. De rassen binnen een groep hebben hetzelfde resistentiespectrum t.o.v. een standaardserie virusstammen. Uit elke groep werden op grond van hun geschiktheid (duidelijkheid en reproduceerbaarheid van de symptomen) één of meer vertegenwoordigers gekozen, waaruit een standaardserie van toetsrassen werd samengesteld (Tabel 2).De 22 stammen en isolaten werden op grond van hun pathogeniteitsspectrum t.o.v. de standaardserie van toetsrassen ingedeeld in tien groepen en subgroepen (Tabel 1). De stammen en isolaten binnen een groep of subgroep hebben eenzelfde pathogeniteitsspectrum (Tabellen 4 en 6) en worden op grond daarvan als identiek beschouwd. De differentiële reacties tussen de rassen van de standaardserie en de virusstammen en-isolaten zijn vermeld in de Tabellen 3 en 5. Voorgesteld wordt om de naam van de eerstbeschreven stam van iedere groep te handhaven en de andere stammen in een groep of subgroep op te vatten als isolaten daarvan.De toetsmethodiek wordt uitvoerig beschreven om standaardisatie van de stammenidentificatie te bevorderen. Ter verklaring van de in de literatuur gevonden tegenstrijdigheden in de differentiële reactie van de toetsrassen wordt een negental mogelijke oorzaken genoemd, o.a. het gebruik van planten van toetsrassen die reeds vanuit zaad met een onbekende stam waren besmet en het gebruik van onzuivere virusstammen (mengisolaten).De auteurs stellen zich verantwoordelijk voor het distribueren (op aanvraag) van kleine zaadhoeveelheden van de toetsrassen en, op beperkte schaal, van in zaad aanwezige zuivere virusstammen aan onderzoekers die betrokken zijn bij de identificatie van de stammen van dit virus. Bovendien zal zaad van de standaardserie van toetsrassen worden gedeponeerd in het National Seed Storage Laboratory te Fort Collins, Colorado, USA, terwijl de virusstammen (in zaad) in bewaring worden gegeven bij de American Type Culture Collection te Rockville, Maryland, USA, waar ze beschikbaar zullen blijven voor verder onderzoek. 相似文献
232.
A new syndrome, characterised by acute respiratory distress and by abnormalities of the skin, hair and thyroid, was the apparent cause of neonatal death in 35 (24 per cent) of 146 piglets sired by a large white boar in four small commercial pig units. The syndrome appears to be of genetic origin, inherited as an autosomal recessive trait. Its similarities with the respiratory distress syndrome (RDS) of the newborn infant and the "barker" syndrome of the newborn foal are discussed. 相似文献
233.
Uterine motility was recorded for several weeks in 10 ovariectomised goats, using small intra-uterine balloons, to study the effects of female sex hormones on uterine activity and reactivity to oxytocin. Oestradiol stimulated uterine contractions and increased both the sensitivity and intra-uterine pressure response to oxytocin. When progesterone was administered in addition to oestradiol, spontaneous uterine motility became irregular with low amplitude contrations; the sensitivity and reactivity to oxytocin was significantly depressed. 相似文献
234.
235.
236.
Modification of the normal plasma protein picture has been studied in plasma samples from cows suffering from spontaneously arisen (17 cases) or experimentally induced acute peritonitis (5 cases) using polyacrylamide electrophoresis. Considerable differences were found in the postalbumin region during peritonitis. One protein component increased in size, while another disappeared. Two weak components in normal samples were replaced by four discrete protein bands. These modifications were not detected in any of 10 plasma samples from cows suffering from other diseases than peritonitis or in any of 35 samples from clinically healthy animals. The modifications were visible 12-16 h after injection of the provoking agent and were remarkably alike from one case to the next. 相似文献
237.
238.
E J Andrews 《American journal of veterinary research》1975,36(7):889-891
Portions of duodenum, jejunum, and ileum from 21 hamsters clinically affected with enteritis were examined for enzymes. Utilizing a variety of techniques, the activities of alkaline phosphatase, nonspecific esterases, leucine aminopeptidase, beta-glucuronidase, and methyl green pyroninophilia were determined. The activities of enzymes normally associated with tissue proliferation and active protein synthesis were decreased, whereas those enzymes associated by cytolysis were increased. 相似文献
239.
Introduction: We evaluated the totally implantable subcutaneous vascular access port (VAP) in 16 cancer patients undergoing intermittent chemotherapy for more than 30 months.
Methods: Ports were surgically placed (The CompanionPort, Norfolk Vet Products, Skokie, Illinois 60076) in the jugular vein of 12 dogs and 4 cats between 1/2002 and 7/2004. Body weight determined polyurethane catheter size (4, 5, 7 fr.). The polysulfone port, surrounded by titanium, was anchored to subcutaneous tissue in the dorsolateral neck and confirmed with C‐arm fluoroscopy. All blood samples were obtained via VAP. Nine anticancer agents, other medications, crystalloids/colloids, and whole blood were administered. Ports were flushed every 4–5 weeks with heparinized saline solution (100 IU/ml). Removed catheters were submitted for bacteriology.
Results: Seven of 16 animals are still alive. VAP were used for 1.5 to more than 30 months with 4–60 injections/port. Catheter tips were visualized from the left atrium distally into the caudal vena cava. Adverse events included post‐operative subcutaneous bruising and/or hematoma (4/16), difficult aspiration (4/16), catheter malposition (1/16), positional flushing (1/16), and occlusion requiring replacement (1/16). No thrombus formation or extravasation was evident. Bacterial colonization without signs of septicemia was observed in 3/4 catheters.
Conclusions: VAP are an effective way of achieving long‐term venous access in the dog and cat. Complications are typically minor and infrequent. 相似文献
Methods: Ports were surgically placed (The CompanionPort, Norfolk Vet Products, Skokie, Illinois 60076) in the jugular vein of 12 dogs and 4 cats between 1/2002 and 7/2004. Body weight determined polyurethane catheter size (4, 5, 7 fr.). The polysulfone port, surrounded by titanium, was anchored to subcutaneous tissue in the dorsolateral neck and confirmed with C‐arm fluoroscopy. All blood samples were obtained via VAP. Nine anticancer agents, other medications, crystalloids/colloids, and whole blood were administered. Ports were flushed every 4–5 weeks with heparinized saline solution (100 IU/ml). Removed catheters were submitted for bacteriology.
Results: Seven of 16 animals are still alive. VAP were used for 1.5 to more than 30 months with 4–60 injections/port. Catheter tips were visualized from the left atrium distally into the caudal vena cava. Adverse events included post‐operative subcutaneous bruising and/or hematoma (4/16), difficult aspiration (4/16), catheter malposition (1/16), positional flushing (1/16), and occlusion requiring replacement (1/16). No thrombus formation or extravasation was evident. Bacterial colonization without signs of septicemia was observed in 3/4 catheters.
Conclusions: VAP are an effective way of achieving long‐term venous access in the dog and cat. Complications are typically minor and infrequent. 相似文献
240.