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91.
The RNA genome of foot- and mouth disease virus strains A5 Westerwald and O1 Lausanne has been reverse-transcribed and cloned in lambdaphages or plasmids. Identification of cDNA-clones containing VP1-specific sequences was achieved by hybridization, restriction mapping, and sequence analysis. VP1-coding cDNA-fragments were subcloned into the expression vector pEX which led to synthesis of fusion proteins with beta-galactosidase. These fusion proteins reacted with anti-VP1 antibodies on a Western blot, but were not capable of inducing neutralizing antibodies to mice. This seemed to suggest a tertiary structure of the VP1-epitopes unlike those of native VP1. Other attempts are discussed to construct VP1-fusion proteins folding similarly to the native viral protein structure.  相似文献   
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Rose plants that are flush harvested exhibit episodic growth patterns. During these crop cycles little biomass accumulation occurs immediately following harvest; and as new shoots emerge a period of rapid shoot growth and biomass accumulation occurs. The temporal changes in whole-plant nutrient and carbohydrate distribution during these crop cycles and the role of storage in new shoot growth are not well documented. The objective of this project was to quantify N, P, K, and total non-structural carbohydrates (TNC) distribution in roots, base stems, base leaves, and new shoots during crop cycles in response to light availability. Plants were grown in solution culture under high or low light (mean daily light integral 45.3 or 13.1 mol m−2 d−1, respectively) during 30–35 day crop cycles. Every five days destructive sampling was used to determine biomass and N, P, K, and TNC concentration of rose plant compartments. N and TNC accumulated in base plant compartments during the first ten days of the crop cycles. N, P, K, and TNC in base plant compartments declined during days 10–25 during a crop cycle concurrent with the rapid growth of flower shoots. N, P, and K storage in base plant parts represents 27, 22, and 24% of the potential N, P, and K required by flower shoots under high light; and 19, 21, and 22% of requirements under low light. TNC storage in base plant parts represents 4–10% of the final biomass of flower shoots. Mobilization of N, P, K, and TNC stored from base plant parts appears to be important during the stage of rapid flower shoot growth when absorption by roots or photosynthesis by shoots was insufficient to meet flower shoot demands. Plant carbohydrate status was improved under high light conditions; storage of N and TNC declined under low light.  相似文献   
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Objectives To report the incidence and evaluate the clinical significance of goniolens bacterial contamination in clinical use in dogs with three different usage protocols and one with an added cleaning protocol. Animals Studied and Methods Three groups of twenty dogs undergoing gonioscopy at a private practice in the UK had the goniolenses swabbed for bacteriology culture and identification prior to placement on the cornea. Three protocols of lens use, with 2 different types of goniolens, were studied. One protocol was then repeated with 21 dogs with a lens cleaning protocol prior to storage. Results Low levels of bacterial contamination were found in all 3 initial groups (10‐15%). No correlation was found between usage protocol used and rate of contamination and no correlation was found between length of storage between use and contamination. All bacteria cultured were considered naturally occurring commensals for the canine eye and environment. The group with a cleaning protocol had a 4.7% contamination rate. This was not statistically different from the non‐cleaning groups. Conclusions The rate of bacterial contamination of goniolenses in clinical practice is low and the bacterial contaminants consist of commensal bacteria, unlikely to be of detriment to the eye. Minimal contamination of the goniolenses was found and this did not appear to be of clinical significance. The introduction of a simple cleaning protocol did not produce a statistically significant reduction in bacterial contamination.  相似文献   
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Ohne ZusammenfassungDiese Abhadlung hat uns der am 15. I. 30 freiwillig aus dem Leben geschiedene Gie\ener Universitätsprofessor wenige Tage vor feinem Tod übersandt. In einem Begleitbrief sagt er, da\ fie gleichfam das Programm einer Geschichte der Forstwirschtslehre darstelle, mit deren Absassung er zur Zeit beschäftigt fet.Das Klingt viel mehr nach Lebens- und Schaffenslust als nach überdru\ oder Verzweiflung. Heute muten uns aber seine hier folgenden mahnenden Worte und Fingerzeige zum rechten Weg wie ein bewu\tes Vermächtnis an seine Fachgenossen auf den Lehrstühlen an. Sie zeigen zugleich, wie ernst H. W. Weber es mit seiner Wissenschaft genommen hat, lassen aber auch seinen schwarzseherischen Geist erkennen, der seinem eigenen Sein zum Verhängnis geworden ift. Er, unberfrtedigt jeden Augenbild von sich und seiner Umwelt arbeitete bis zu seinem le\ten Tag an der Förderung seines Faches, leider ohne durch diese Arbeit die faustische Erlösung zu finden.Wir danken ihm für manche wertvolle Arbelt, indemwir sein Andenken ehren und weden seiner demnächst nach in einem Nachruf aus Feder eines Freundes gedenken.  相似文献   
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Summary The thrust out-reflex of the back beetles is useful to the breeding galleries of bore-meal and other substances. The beetles also avert with this reflex other insects, who try to invade the breeding galleries. Then the bark beetle thrust out its abdomen and often that means the ruin of the beetle. The enemy — f. i.Thanasimus formicarius L. — has the opportunity to kill the bark beetle when he reaches its abdomen.  相似文献   
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