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1.
Early assessment of processing strawberries for colour   总被引:1,自引:0,他引:1  
Hedley Williams 《Euphytica》1977,26(3):841-845
Summary It is possible to select strawberry cultivars that give a satisfactory, naturally coloured canned product as an alternative to the commercially dyed one. Spectrophotometric measurements of the syrup from cans, the canned fruit and fresh fruit were compared with visual scoring. A preliminary screening for colour based on visual assessment of fresh flesh colour is possible.  相似文献   
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Apoptosis (programmed cell death) could be considered as a physiological process that takes part in a healthy organism, which helps to maintain organism homeostasis. The visible deterioration of semen quality and the number of germ cells is accompanied by a seasonal decrease of the reproductive activity in some species. This post-effect cascade is caused by apoptosis, which is the primary mechanism responsible for the elimination of germ cells during spermatogenesis. The aim of our study was to assess apoptotic changes in the epithelium germinativum in cat testes at different ages. One hundred and two pairs of testes were obtained from domestic cats aged between 4 months and 10 years. The paraffin-embedded tissue sections were labelled using the Oncogene and Calbiochem Research Products DNA Fragmentation Detection Kit (Cat# QIA21; Darmstadt, Germany), which allows the recognition of apoptotic nuclei in tissue sections with Fragment End Labelling (FragELTM) of DNA. The activity of apoptotic processes in cat testes collected from the spring-summer period compared with the autumn-winter season revealed that, 59.42% and 51.51%, respectively, males testes were characterized by insignificant changes. The obtained data revealed a distinctive apoptotic changes in the young animal testes before spermatogenesis onset. An intensification of programmed death cells in the epithelium germinativum in the elder cats (between 3–6 and 6–10 years) was not observed. Apoptotic changes slightly intensified in cats aged between 12 and 36 months.  相似文献   
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Objective   To examine the incidence of positive results in a complement fixation test (CFT) and enzyme-linked immunosorbent assay (ELISA) for Chlamydophila abortus in Australian sheep and how this incidence differs with state of origin, age, sex, breed and property. To examine the consequences in relation to rejection of breeder sheep for export.
Design   Collection of blood samples from 891 sheep on 109 properties in southern Australia. All samples had a unique, coded property identification.
Procedure   The samples were tested using the Institut Pourquier Chlamydophila abortus antibody ELISA (rELISA) and a CFT. Residual maximum likelihood analyses of the sample to positive ratio of the corrected optical density for the rELISA and generalised linear mixed model analyses of the CFT outcomes were carried out.
Results   The sample to positive ratio of the corrected optical density values of the rELISA did not differ between sex, age, breed or state of origin, but differed greatly between properties. The CFT outcome did not differ between age, breed or state of origin, but differed greatly between properties and was more often positive with rams than with ewes.
Conclusion   Positive outcomes to C. abortus antibody tests are very common in Australia. Rams have a particularly high incidence of positive results with the CFT. Rejection of sheep and property consignments is likely to be very common with all tests and situations examined except for the CFT (at 1:32 dilution) in ewes.  相似文献   
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Sex steroids in synergy with prostaglandins (PG) are involved in the regulation of cyclic ovarian function. In this study, we investigated the mRNA expression of three genes involved in arachidonic acid (AA) metabolism and hence PG production in domestic cats: PG‐endoperoxide synthase (PTGS2), PGF synthase (PGFS) and PGE2 synthase (PGES). Feline endometria (n = 16) were collected at oestrus and mid and late phases of pseudopregnancy. In addition, the effects of E2 and/or P4 on PG secretion and gene expression on endometrial explants were studied in an in vitro culture system. Expression levels of all examined genes were up‐regulated at the mid phase of pseudopregnancy. The effects of E2 and/or P4 treatment on both PG secretion and expression of the genes were observed after 12 h of culture. Expression of PGES was significantly up‐regulated by E2 plus P4 at oestrus and the mid phase of pseudopregnancy and was also up‐regulated by a single treatment with P4 at late pseudopregnancy (p < 0.05). Simultaneous incubation with E2 and P4 up‐regulated PTGS2 gene expression at oestrus and mid‐luteal phase (p < 0.05). Progesterone plus E2 significantly increased PGE2 secretion at oestrus and the mid phase of pseudopregnancy. However, treatment with E2 and/or P4 affected neither PGF secretion nor PGFS expression at any phase after 12 h of culture. The overall findings indicate that genes involved in PG synthesis are up‐regulated at the mid phase of pseudopregnancy. An increase in PGE2 secretion and up‐regulation of PGES and PTGS2 are the main responses of the endometrium to treatment with E2 and P4 at oestrus and the mid phase of pseudopregnancy in the cat. These data support the hypothesis that ovarian sex steroids via endometrial PGE2 are involved in endocrine homoeostasis, especially at oestrus and the mid, but not the late, phase of pseudopregnancy in cats.  相似文献   
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A possible role of breeding activities in the composition of the microbial population in stallions' external genitalia (EG) and the relationship between micro‐organisms colonizing the skin of the abdomen and the ones colonizing the EG have not been studied. In experiment 1, EG microbiological samples were collected from 41 stallions used for both natural cover and semen collection (BST) and from 18 non‐breeding stallions (NBST). A higher (p < 0.05) frequency of isolation of potentially pathogenic species was found for BST. Age did not influence number of micro‐organism species isolated both in BST and NBST. In experiment 2, the microbial content of the EG and semen was compared in 23 BST. Most micro‐organisms isolated from the EG were present in semen, albeit with a numerically lower prevalence. In 7 stallions, six microbial species isolated from semen were absent from the EG cultures, suggesting contamination by the operator. In experiment 3, a numerically higher number of micro‐organism species was isolated from the EG of 31 stallions, than from their skin of the ventral abdomen in contact with the penis or from the skin of the thorax. With the sole exception of Escherichia coli, potentially pathogenic bacteria were only isolated from the EG but not from the skin. Results suggest that breeding activity increased the number of species colonizing the EG; most species isolated from the EG were also found in semen even if with a lower frequency, and additional semen contamination seemed to occur during its manipulation. Many micro‐organism species of the skin were also isolated from the penis, but independently of being or not in contact with the penis, skin did not seem to provide an adequate environment for the growth of potentially pathogenic bacteria that were isolated from EG, with the sole exception for E. coli.  相似文献   
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Nonsteroidal anti‐inflammatory drugs (NSAIDs) are widely used to provide analgesia in clinical veterinary medicine, but there are few objective data evaluating this effect under controlled conditions in cats. Analgesia is more difficult to detect with acute analgesiometry after NSAIDs than after opioids. This investigation aimed to adapt the feline thermal analgesiometry method previously employed with opioids ( Dixon et al. 2002 ) for use with NSAIDs. Ketoprofen, a COX1 inhibitor licensed for cats was chosen. Six cats (2 neutered, four entire females, weighing 2.2–5.4 kg) were studied in two blinded randomized crossover trials each at least 2 weeks apart. Thermal thresholds (TT) were measured using the thermal threshold‐testing device previously developed for cats. A heater element and temperature sensor in a small probe were held at constant pressure against the cats' shaved thorax with an elasticized band. Skin temperature was recorded before each test, then the heater activated. When the cat responded by flinching, turning or jumping the heater was turned off and the temperature recorded. In the first study TT were measured following subcutaneous (SC) injection of ketoprofen (2 mg kg?1) or a similar volume of saline. In the second study, prior to TT, and under isoflurane restraint, a mild inflammatory focus was produced at the probe site by five SC injections of 5 mg kaolin in 0.1 mL saline at each corner and in the center of a 1.5‐cm square. Saline or ketoprofen as in the first study were injected at the same time. Three baseline temperatures were recorded before any injections were given. Thermal thresholds were measured at 1 and 2 hours and then two‐hourly for 24 hours. Data were analysed using anova . Baseline skin temperature increased (37.3 ± 0.5–38.1 ± 0.8 °C) 24 hours after saline injection in study 2 (p < 0.05) but did not change after any other treatment. Thermal thresholds decreased (40.0 ± 1.3 to 39.1 ± 0.4 °C) 16 hours after ketoprofen in study 1 (p < 0.05) and increased (41.6 ± 1.5–44.8 ± 6.1 °C) 16–24 hours after ketoprofen in study 2 (p < 0.05), with no significant changes after saline. No obvious increase in sensitivity to thermal stimulation after kaolin injection was detected although obvious inflammation was present for up to 36 hours and the cats responded to digital pressure at the treated site. The method detected some effects of a COX1 selective NSAID and may be suitable for future NSAID studies in cats. However, a pressure stimulus ( Dixon et al. 2000) may prove better than thermal, and it requires investigation.  相似文献   
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