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1.
Optimized palm press fiber composites of poly(?-caprolactone)/poly(lactic acid) were produced and their mechanical and thermal properties were studied. The composites were melt blended using twin screw extruder and test specimens were produced by injection molding. The composites mechanical and thermal performances were tested using standard methods. The incorporation of dicumyl peroxide as compatibilizer significantly increased the tensile strength, flexural modulus and impact strength of the composites as compared to the uncompatibilized composites. Crystallization temperature of the composites initially increased after which it dropped as fiber load increased. The composites melting point and percentage crystallinity slightly decreased as fiber load increased.  相似文献   
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Two groups of one-day-old Peking ducklings (Groups I and II, 12 birds/group) were inoculated orally with Brachyspira pilosicoli and two groups with B. alvinipulli (Groups III and IV, 12 birds/group). T-2 toxin was added to the feed of Groups II and IV in a dose of 1 mg/kg of feed. Groups V and VI served as uninfected control groups (ducks of Group VI received T-2 toxin). The body weight gain of the ducks was measured and clinical signs were monitored continuously. The birds were sacrificed and necropsied on days 7, 14, 21, and 28 post infection (PI). The liver, spleen, kidney, thymus, bursa of Fabricius, ileum, caecum and colon were examined histologically. Culturing of Brachyspira spp. and immunohistochemistry were performed from the sampled parts of the intestines as well. No gross pathological or histological lesions that could be associated with B. pilosicoli or B. alvinipulli were detectable in the intestinal mucous membrane including the colonised intestinal glands. Mortality did not occur during the experimental period. Decrease in body weight gain was significant in the T-2-toxin-treated groups, and it was slight (not significant) in the Brachyspira-infected groups. Crust on the beaks, necrosis, crusting and ulceration in the mucous membrane of the oral cavity and on the skin of the feet, atrophy of the thymus and bursa of Fabricius due to the effect of T-2 toxin, accompanied by lymphocyte depletion, were observed. These lesions were most prominent on days 14 and 21 PI but were seen on day 28 PI as well. Immunohistochemical detection and reisolation of B. pilosicoli and B. alvinipulli were successful on days 7, 14, 21 and 28 days from different segments of the intestine of certain birds, but no significant difference was observed in the colonisation rate between the T-2-toxin-treated and the untreated groups.  相似文献   
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Improved rice lines were developed frome three parents with the resistance or tolerance to bacterial leaf blight, blast and drought stress, respectively, using single-, double- and three-way crosses. The improved lines were assessed for agro-morphological and yield traits under non-drought stress (NS) and reproductive-stage drought stress (RS) treatments. The mean comparison of traits measured between parent plants and progenies (improved lines) were similar, and there were significant and non-significant differences among the parents and improved lines (genotypes) under NS and RS. Smilarly, there was significant and non-significant differences in the interaction among both parent varieties and improved lines for NS and RS. Cluster and 3D-model of principal component analysis did not generate categorical clusters according to crossing methods, and there were no exclusive crossing method inclined variations under the treatments. The improved lines were high-yielding, disease resistant, and drought-tolerant compared with their parents. All the crossing methods were good for this crop improvement program without preference to any, despite the number of genes introgressed.  相似文献   
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Nutritional support in critically ill patients is a fundamental principle of patient care. Little is known about gallbladder motility during the interdigestive phase and in response to enteral feeding. The objective of this study was to investigate the effect of enteral feeding on gallbladder function in dogs. The cholagogue meal (Lipofundin infusion) was applied in four anatomical positions (jejunum, duodenojejunal junction, descending duodenum, stomach) in five healthy Beagle dogs. Gallbladder volume (GBV) was monitored by ultrasonography. Lipofundin infusion given through the feeding tube caused a maximal gallbladder contraction of 9.2% (range 3.7-13.9%) in the jejunum, 16.5% (9.1-22.1%) at the duodenojejunal junction and 26.3% (22.8-29.5%) in the descending duodenum. When the cholagogue meal was given through the mouth, it caused a mean 33.8% (28.6-46.5%) maximum gallbladder contraction in the same animals. In conclusion, we can establish that the ultrasound-guided gallbladder emptying method proved to be a useful technique for monitoring the cholagogue effect of Lipofundin meal applied in different anatomical positions of the intestine. The deeper the position of application, the smaller and shorter gallbladder contraction was evoked.  相似文献   
5.
The effects of graphene nanoplatelets (GNP) and multiwall carbon nanotube (MWCNT) hybrid nanofillers on the mechanical and thermal properties of reinforced polyethylene terephthalate (PET) have been investigated. The nanocomposites were melt blended using the counter rotating twin screw extruder followed by injection molding. Their morphology, mechanical and thermal properties were characterized. Combination of the two nanofillers in composites formulation supplemented each other which resulted in the overall improvement in adhesion between fillers and matrix. The mechanical properties and thermal stability of the hybrid nanocomposites (PET/GNP1.5/MWCNT1.5) were significantly improved compared to PET/GNP3 and PET/MWCNT3 single filer nanocomposites. However, it was observed that GNP was better in improving the mechanical properties but MWCNT resulted in higher thermal stability of Nanocomposite. The transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) revealed uniform dispersion of the hybrid fillers in PET/GNP1.5/MWCNT1.5 nanocomposites while agglomeration was observed at higher filler content. The MWCNT prevented the phenomenal stacking of the GNPs by forming a bridge between adjacent GNP planes resulting in higher dispersion of fillers. This complimentary geometrical structure is responsible for the significant improvement in the thermal stability and mechanical properties of the hybrid nanocomposites.  相似文献   
6.
The occurrence of equine arteritis virus (EAV) induced equine abortions was studied with different laboratory methods during a 3-year period. Tissue samples from 96 aborted equine foetuses or newborn foals were collected from 57 farms located in different parts of Hungary. Virus isolation, polymerase chain reaction (PCR), immunohistochemistry and serology were used for the detection of EAV infection. The overall seroprevalence of EAV infection in mares was 65%. EAV induced abortion was diagnosed in eight (8.3%) cases from six (10.5%) herds. Abortion was sporadic in all herds except for one, where epidemic abortion happened. Fetal serology in six (75%) cases, the virus isolation in one (12.5%) case whereas PCR in all of the four investigated cases were positive. The virus could be observed with immunohistochemistry in seven (87.5%) cases mostly in the spleen followed by other organs and the allantochorion. In conclusion, PCR and immunohistochemistry seem to be the most sensitive and useful tests for the diagnosis of EAV induced equine abortion.  相似文献   
7.
Medical records of 80 dogs diagnosed with acute pancreatitis during a 4-year period were evaluated regarding history, breed predilection, clinical signs and additional examination findings. Cases were selected if compatible clinical symptoms, increased serum activity of amylase or lipase and morphologic evidence of pancreatitis by ultrasonography, laparotomy or necropsy were all present. Like in other studies, neutered dogs had an increased risk of developing acute pancreatitis. Although breed predilection was consistent with earlier reports, some notable differences were also observed. Apart from Dachshunds, Poodles, Cocker Spaniels and Fox Terriers, the sled dogs (Laikas, Alaskan Malamutes) also demonstrated a higher risk for pancreatitis according to our results. Concurrent diseases occurred in 56 dogs (70%), diabetes mellitus (n = 29, 36%) being the most common. Clinical signs of acute pancreatitis were similar to those observed in other studies. The study group represented a dog population with severe acute pancreatitis, having a relatively high mortality rate (40%) compared to data of the literature. Breed, age, gender, neutering and body condition had no significant association with the outcome. Hypothermia (p = 0.0413) and metabolic acidosis (p = 0.0063) correlated significantly with poor prognosis and may serve as valuable markers for severity assessment in canine acute pancreatitis.  相似文献   
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鸡免疫系统的抑制现象称之为免疫抑制,是由不良的环境条件、落后的管理方式、营养缺乏以及疾病感染所引起的,可导致严重的生产性能下降和经济损失。预防免疫抑制的关键在于采取多种切实有效的措施。  相似文献   
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