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941.
Laura C. Setyo Shannon L. Donahoe Patrick L. Shearer Penghao Wang Mark B. Krockenberger 《Journal of veterinary diagnostic investigation》2023,35(2):109
Urothelial carcinomas (UCs), also known as transitional cell carcinomas, are the most common canine urinary tract neoplasms. Tyrosine kinases (TKs) are enzymes that tightly regulate cell growth and differentiation through phosphorylation. Receptor TK (RTK) inhibitors are currently used to treat UCs. Toceranib phosphate (Palladia; Pfizer) is an RTK inhibitor that blocks the activity of vascular endothelial growth factor receptor 2 (VEGFR2), platelet-derived growth factor receptor–alpha and –beta (PDGFR-α, -β), FMS-like tyrosine kinase 3, stem cell factor receptor (KIT, kinase inhibitor targeting), and colony stimulating factor receptor. To better understand UCs and validate treatment targets, we performed immunohistochemical staining for RTKs, as well as a novel target, cyclin-dependent kinase 4 (CDK4, a central regulator of the mammalian cell cycle), on formalin-fixed, paraffin-embedded tissues from bladder biopsies from 17 dogs with UCs, 17 dogs with cystitis (diseased controls), and 8 normal dogs (negative controls). Although immunohistochemical scores could not be extrapolated to prognostic value, response to treatment, and outcome of patients with UC, we demonstrated expression of PDGFR-β and VEGFR2 in UCs; all UC samples staining positively for VEGFR2. Minimal positive staining for KIT was noted in the tumor samples. CDK4 staining intensity was significantly weaker in UCs compared with normal and cystitis bladder samples. The intense staining of VEGFR2 in UC cells suggested that VEGFR2 may be of prognostic and/or therapeutic value in dogs with UC. Overexpression of VEGFR2 in UC cells validates this receptor as a treatment target in UC. 相似文献
942.
Ten years of fluxes and stand growth in a young beech forest at Hesse, North-eastern France 总被引:1,自引:0,他引:1
André Granier Nathalie Bréda Bernard Longdoz Patrick Gross Jérôme Ngao 《Annals of Forest Science》2008,65(7):704-704
943.
F. Patrick Graz 《European Journal of Forest Research》2008,127(2):165-171
Forestry inventory practices have, in the past, concentrated on obtaining information primarily required for timber management.
To assess the ecological impact of exploitation, particularly under continuous cover forest management, diversity measures
are required that consider the structural diversity in a forest stand. The measure of surround that was initially developed
in Germany may be used to quantify the spatial interspersion of different tree size classes as a measure of spatial diversity.
While the measure of surround has been applied to practical problems in the past, little is known about its actual performance
in relation to stand compositions. This study investigate the behaviour of the index using a number of simulated age class
distributions under various degrees of interspersion to provide a norm against which it may be compared. The measure of surround
applied to diameter distributions is closely related to the diameter structure of a stand. When diameter classes are interspersed
completely randomly within a stand the relative cumulative frequency of the diameter class provides an estimator of the size
specific measure of surround. This provides a baseline from which the index may be interpreted. 相似文献
944.
Patrick V. Vail Donald L. Hostetter Darlene F. Hoffmann 《Integrated Pest Management Reviews》1999,4(3):231-257
A number of the members of the Noctuidae (subfamily Plusiinae) are polyphagous insects that infest a variety of economically important crops world-wide. These hosts include but are not limited to cotton, vegetable and field crops and also such specialty crops as mint. Many of these crops require multiple applications of chemical pesticides to protect them from various loopers and other economic pests. One proposed alternative to the use of chemical pesticides to protect these crops is the development of insect-specific viruses of the family Baculoviridae. Hundreds of these viruses of the genus Nucleopolyhedrovirus have been isolated, many from economically important Lepidoptera. The advent of the discovery that some of these viruses may have a broad host range increased the interest in the development of them as microbial agents throughout the world. The broad host range (over 30 species in some cases) provided the possibility to control not only one species, but a complex of lepidopterous pests infesting specific or multiple crops. From the 1960s to the present, extensive basic and applied research has been conducted on the multi-nucleocapsid (MNPV) forms within which a broad host range appears to be characteristic. Of these, the virus isolated from the alfalfa looper, Autographa californica (Speyer) (AcMNPV) has been the most studied, particularly as related to microbial control. Two of the viruses isolated from loopers have been registered in the USA. Although efficacy has been demonstrated for loopers, there is a paucity of data on the other important species that may simultaneously infest looper hosts. Because of their relatively slow action, the viruses will probably be used in integrated programs with chemical pesticides applied during critical periods of high population pressure. Further research needs to be conducted to establish efficacy for other hosts, improved production methods either in vivo or in vitro, increased field persistence as related to timing and frequency of applications, and finally the utility of genetically engineered MNPVs as microbial pesticides. The potential of these organisms has been demonstrated and new developments are being made to increase the overall efficiency and economics of their use. These improvements can only increase interest in use of the baculoviruses in pest management systems for loopers and other pests. 相似文献
945.
946.
Ronaldo O. Cavalli Gerben Menschaert Patrick Lavens Patrick Sorgeloos 《Aquaculture International》2000,8(1):41-58
The effects of increasing levels of dietaryphospholipids (PL) on the reproductive performance,egg and larval quality, and lipid composition offemales of the freshwater prawn Macrobrachiumrosenbergii were investigated. Three isolipidic dietscontaining similar amounts of highly unsaturated fattyacids but varying levels of PL (0.8, 2.4 and 4.6%)were fed during 180 days to three groups of eightfemales originating from Thai ponds. No significantdifferences were observed for fecundity, egg size andhatchability, starved larvae size, and size, survivaland tolerance to stress of 8 day-old larvae.Similarly, no major differences in the lipidcomposition of the midgut gland, ovaries and muscletissue of females could be detected. Results indicatethe lack of need of dietary supplementation of PL forM. rosenbergii broodstock, as previouslyreported for earlier life stages. It is suggested thatthe basal level of 0.8% dietary PL was sufficient tomeet the dietary demands of the prawn broodstock. ThePL requirements of M. rosenbergii broodstock, ifany, may be satisfied in commercial feeds through theinclusion of ingredients containing some phospholipidsendogenously. 相似文献
947.
Location of Pm3g, a powdery mildew resistance allele in wheat, by using a monosomic analysis and by identifying associated molecular markers 总被引:5,自引:0,他引:5
Pierre Sourdille Patrick Robe Marie-Hélène Tixier Gérard Doussinault Marie-Thérèse Pavoine Michel Bernard 《Euphytica》1999,108(3):193-198
A segregating population of doubled-haploid lines issued from the cross between the wheat (Triticum aestivum L. em. Thell) cultivars Courtot, resistant to several isolates of powdery mildew (Blumeria graminis DC. f. sp. tritici Em. Marchal), and Chinese Spring (susceptible) was used to map Mlar, a gene carried by Courtot and conferring resistance to this pathogen. The assignation of Mlar using monosomic lines of Courtot was confirmed by the mapping analysis. Mlar was located on the short arm of the chromosome 1A, in the vicinity of the locus XGli-A5 coding for storage proteins. This result was in accordance with those demonstrating that Mlar was an allele of the Pm3 locus (Pm3g), a gene also involved in the resistance to powdery mildew.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
948.
Summary Two nonparametric statistical techniques are presented which allow the user to evaluate the effect of a treatment on an n-dimensional
set of variables associated with forest products. The multi-response permutation procedures (MRPP) are a broad category of
permutation techniques based on a variety of distance functions. Earlier work on this subject has demonstrated that when the
distance function is selected appropriately, one-dimensional MRPP represent a rational alternative to traditional comparative
statistical analysis techniques, such as the Student's t-test (t-test). In the work presented herein, MRPP are broadened to
include analyses on the effect of a treatment on data were containing multiple variables which may be correlated. These tests
are a MRPP based on Euclidean distance (MRPP-E) and a MRPP motivated by Hotelling's T2 test (MRPP-H) which can account for the variance-covariance structure of the data. Four hundred eighteen data points representing
the moduli of elasticity (MOE) and rupture (MOR) of eight foot-long (244 cm), nominal 2 × 4 inch2 (51 × 102 mm2), No. 2 grade, Douglas-fir, dimension lumber from seven growing regions in the western United States were selected for use
in this study. Data were analyzed using one- and two-dimensional, classical, parametric techniques (i.e. t-test and Hotelling's
T2 test) and the more intuitive and nonparametric MRPP in similar dimensions. The results indicated that the MOE demonstrated
some degree of sensitivity to the growth region, while the MOR proved to be insensitive. Also, considerable differences in
inference drawn regarding the presence of statistically significant differences between data sets existed as a function of
the analytical test method used. The unique structure of the data encountered in this study showed that MRPP-E was insufficiently
sensitive to the variance-covariance structure of the data. Visual examination of the data suggested that MRPP-H is more appropriate
for the present data than MRPP-E.
Received 7 October 1998 相似文献
949.
Ariadna Chediack Patrick J Liesch Hailey N Shanovich Brian H Aukema 《Journal of insect science (Online)》2022,22(4)
There is a lack of knowledge of the arthropod communities in both wild hazelnut and cultivated hybrid hazelnut ecosystems in the Midwestern United States. Our goal was to characterize the composition of these arthropod communities in hazelnut plantings. We surveyed six experimental plantings of hazelnuts in Wisconsin and two in Minnesota during growing seasons, from May 2017 to August 2021. We used four methods to survey the arthropod community of these plantings: ad libitum survey of specimen observations and collection, dissection of hazelnut buds and nuts, cone traps placed on the ground, and beat sheet sampling of plants. We registered 116 different morphospecies of five classes and 83 families. Arthropods with known feeding habits were grouped into four guilds: 59 herbivores, 36 carnivores (predators, parasites, and parasitoids), 4 decomposers (detritivores and scavengers), and 4 omnivores. While we registered 12 herbivorous species that could potentially cause damage to hazelnuts, we directly observed nine of them feeding upon or damaging plant parts: Phytoptus avellanae s.l. Nalepa (Eriophyoidea: Phytoptidae), Curculio obtusus Blanchard and Strophosoma melanogrammum Förster (Coleoptera: Curculionidae), Popillia japonica Newman (Coleoptera: Scarabeidae), Parthenolecanium sp. (Hemiptera: Coccidae), Euschistus servus euschistoides Say (Hemiptera: Pentatomidae), aphids (Hemiptera: Aphididae), Acleris sp., and Choristoneura rosaceana Harris (Lepidoptera: Tortricidae). We also registered eight species of parasites or parasitoids that could offer biocontrol services in the cropping system. These findings provide a foundation for future targeted studies on potential pests and beneficial arthropods, as well as ecological interactions within the hybrid hazelnut ecosystem in the Midwest. 相似文献
950.
Neil Wang S N M Mandiki Emilie Henrotte Abdel-Ghany Bouyahia Guillaume Mairesse Carole Rougeot Charles Melard & Patrick Kestemont 《Aquaculture Research》2009,40(3):376-383
The aim of this preliminary study was to evaluate the influence of different feeding regimes on the quality of reproduction in pikeperch. Three diets were tested: forage fish (FF), a commercial dry feed (DD) and a mix of both (FD). The diets were given to fish throughout a complete reproductive cycle. During the spawning season, couples were injected with human chorionic gonadotropin (hCG) and let to spawn on nests. Proportion of running males, spawning and hatching success and larval quality (weight, length, body protein, total lipid, fatty acid and lipid class compositions and resistances to osmotic shock and starvation stress tests at hatching) were evaluated. The proportion of running male was lower in the DD group than in the FF and FD groups (54% for DD against 76–89% for FF and FD). In addition, 25%, 62.5% and 75% of injected couples gave spawning that hatched in DD, FF and FD groups respectively. Larval quality parameters were not significantly different between treatments. The results indicate that overall quality of reproduction was higher in FF and FD treatments than in DD. It suggests that the dry feed used was not totally adequate for pikeperch reproduction. Relations between breeder reproductive performances and the feed compositions are discussed. 相似文献