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61.
Changes in the yields of the oleoresin and content of pungent bioactive principles: [6], [8], [10] gingerols and [6] shogaol of Jamaican ginger ( Zingiber officinale) were investigated during different stages of maturity (7-9 months). Ethanolic oleoresin extracts were prepared (95%, w/w) by cold maceration of dried ginger powder, and their percentage yields were calculated (w/w). The pungent bioactive principles in the ginger oleoresin were extracted with methanol and quantitatively analyzed by high performance liquid chromatography (HPLC). Ginger harvested at 8 months from Bourbon, Portland had the highest oleoresin yield (8.46 +/- 0.46%). [6] Gingerol was found to be the most abundant pungent bioactive principle in all the oleoresin samples investigated, with the 9 months sample from Bourbon, Portland containing the highest level (28.94 +/- 0.39%). The content of [6] gingerols was also found to be consistently high (7-9 months) in oleoresin samples from Johnson Mountain, St. Thomas (15.12 +/- 0.39 to 16.02 +/- 0.95%). The results suggest that Bourbon in Portland may be the most ideal location for cultivating ginger for high yields and quality, however, Johnson Mountain in St. Thomas could prove to be the least restrictive location, allowing for harvesting of good quality material throughout the maturity period (7-9 months).  相似文献   
62.
Intravenous anesthesia in the horse: Comparison of xylazine-ketamine and xylaxine-tiletamine-zolazepam combinations. Six healthy adult horses were anesthetized twice at random with following intravenous combinations: 1.1 mg/kg of body weight (BW) of xylazine followed by 2.2 mg/kg BW of ketamine (X-K) and 1.1 mg/kg BW of xylazine followed by 1.65 mg/kg BW of tiletamine-zolazepam (X-TZ). The modifications of some cardiorespiratory parameters and the duration of anesthesia were evaluated and compared for the 2 protocols used. Few significant differences were observed between the 2 protocols in regard to the cardiorespiratory parameters measured. The respiratory rate was lower (7 breaths per minute) and the heart rate was higher (34 beats per minute) with the X-TZ combination. The duration of anesthesia with this technique was 33 +/- 3 minutes (X +/- Sx) and longer than with X-K (18 +/- minutes (X +/- Sx)). Superficial analgesia lasted 14,5 +/- 3 minutes with the X-K combination and 31,7 +/- 3,2 minutes for the X-TZ combination. The 2 protocols are associated with a reduction of PaO2.  相似文献   
63.
The use of alpha-naphthyl acetate esterase (ANAE) as a T cell marker in some other species and the broad correlation of incidence of ANAE-positivity and E rosette-formation in the pig suggest that ANAE-staining may be a T-cell marker in the pig. However, by studying the staining of lymphocytes within a variety of rosettes in fixed preparations a similar incidence of pig blood lymphocytes were found to be ANAE+ among T cells (E rosettes formed in dextran), B cells (antiglobulin rosettes) and Fc-gamma receptor-bearing B and T cells (EA rosettes in saline and dextran): complement (C') receptor-bearing cells showed a higher incidence of staining than other lymphocytes. Analysis of staining morphology suggested that certain morphologies within the B and T lineages may be confined to subpopulations. Thus ANAE positivity is certainly not a marker identifying blood T lymphocytes but could be of some value indicating subpopulations of B and T lymphocytes.  相似文献   
64.
Two Bordetella bronchiseptica mutants, lacking the adenylate cyclase (Cya) or both Cya and pertactin (Prn), were compared with their parental strain NL1013 in their abilities to colonize the nose of neonate piglets and to induce local and systemic antibody responses against filamentous hemagglutinin (FHA) after intranasal (i.n.) inoculation. The number of bacteria recovered and the duration of infection in the nasal secretions were greater for the wild-type parent strain than for the Cya-deficient mutant, indicating that Cya plays an important role during B. bronchiseptica colonization of the nasal cavity. The double mutant did not colonize the nasal cavity and was less able to adhere to epithelial cells in vitro than the other two strains, supporting the hypothesis that Prn plays a major role in cell adhesion. In piglets inoculated with the wild type strain, anti-FHA IgM was found in the nasal secretions one week after inoculation, followed two weeks later by anti-FHA IgA; their presence was concomitant with decreases in bacterial counts. Anti-FHA IgG appeared at six weeks after infection in the serum. In contrast, i.n. inoculation with either mutant failed to induce a nasal secretory antibody response but did induce an earlier and higher IgM response in the serum than inoculation with the wild type strain. However, only the Cya-deficient mutant was able to prime the piglets for the development of a secondary nasal IgM and serum IgG response to FHA after intranasal inoculation with the wild type B. bronchiseptica.  相似文献   
65.
OBJECTIVES: TO define the mode of inheritance of dermoid sinus. METHODS: A chi-squared analysis was performed on data from 46 litters produced between 1990 and 2001. Data were corrected to avoid bias in the segregation ratio. RESULTS: In data from 57 litters (n=492), 82 dermoid sinus positive offspring were observed. The frequency of affected offspring in the Swedish Rhodesian ridgeback population is estimated to be between 8 and 10 per cent. CLINICAL SIGNIFICANCE: Bias in heredity pattern may be caused by undetected dermoid sinus type V. Improved clinical diagnosis of all dermoid sinus types is therefore crucial.  相似文献   
66.
OBJECTIVE: To measure the ocular surface area, scleral thickness, and the aqueous and vitreous humor volumes in the canine and equine eye. Animals studied Fourteen canine and 16 equine cadaver eyes. PROCEDURE: Eyes were measured either fresh or following fixation in formalin. Ocular surface area was calculated using the fluid displacement method. Globes were hemisected and aqueous and vitreous humor were collected and quantitated. Scleral thickness was measured by digital caliper, by image projection, and by ultrasonic biomicroscopy (UBM). RESULTS: Mean +/- standard deviation (SD) scleral surface areas in canine and equine eyes were 12.87 +/- 2.24 and 57.23 +/- 5.63 cm2, respectively. Mean +/- SD aqueous humor volume was 0.77 +/- 0.24 in the dog and 3.04 +/- 1.27 mL in the horse. Mean vitreous humor volume was 1.7 +/- 0.86 mL for the canine eye and 26.15 +/- 4.87 mL for the equine eye. In canine and equine eyes, the sclera was thinnest at the ocular equator: 0.34 +/- 0.13 mm (canine) and 0.53 +/- 0.1 (equine). There were no significant differences between the direct caliper and projected thickness measurements or differences between measurements in the superior, inferior, nasal, and temporal quadrants of the eye. Scleral thickness in fresh tissue was greater than in fixed tissue at most sites. CONCLUSIONS: The UBM measurement method appeared to be most consistent and reproducible when compared to direct measurement techniques. Formalin fixation of the eyes was associated with significantly thinner scleral tissue than with fresh ocular tissue.  相似文献   
67.
In humans, regulatory T (T reg) cells are known to play a critical role in both the regulation of immune homoeostasis and the progression of cancer. However, there is little information about the identification, characterization and the function of T reg cells in canine tumours. We identified T reg cells in 28 canine seminoma samples using a Forkhead box P3 (Foxp3) antibody and investigated the relationship between T reg cell infiltration and histopathological features of classical and spermatocytic seminomas (SE and SS, respectively). The Foxp3 protein showed nuclear immunostaining in infiltrating lymphocytes, and Foxp3+ cells were diffused or focally distributed in seminoma tissues. Foxp3+ cells were frequently present in the SS histotype, in seminomas that showed no evidence of tumour cell invasion into the vessels and in seminomas showing a diffuse growth pattern with three cell types. Neither the SE/SS histotype nor the histopathological features of the tumour correlated with Foxp3+ cell counts. These results indicate that Foxp3+ T reg cells may be associated with a less malignant histological phenotype or may not play a critical role in the immune response of canine seminomas. Moreover, Foxp3+ T reg cells may be associated with SS seminoma, but further studies, involving a larger number of samples, are required to better understand whether these cells play a critical role in the immune response in canine seminomas. This is the first report to demonstrate the characteristics of T reg cell infiltration in canine seminoma.  相似文献   
68.
S. Salmon  J.F. Ponge 《Pedobiologia》2012,55(6):295-301
Although considerable work has been done investigating the factors that underlie species trait assemblages in emblematic groups such as plants and vertebrates, more remains to be done in belowground invertebrate species. For this group, in particular, relationships between species traits and habitat preferences are still a matter of debate. To eludicate upon the relationships, springtails were sampled in a heterogeneous landscape centered on the Sénart forest, near Paris (northern France), which represented the largest possible array of five environmental gradients (humus forms, vegetation, moisture, vertical strata, and seasons) over which Collembola are known to be distributed. The distance between samples varied from a few cm to several km. Canonical correspondence analysis using species (128) as observations and species trait attributes (30) and habitat indicators (82) as dependent and independent variables, respectively, allowed us to discern whether species habitats and species trait assemblages were related and which trends could be found in trait/environment relationships. It was concluded that, within the studied area, species habitats were significantly associated with species trait assemblages. The main gradient explaining the distribution of species traits combined the vertical distribution of habitats (from the mineral soil to plant aerial parts), and the openness of the environment, suggesting that a complex of many ecological factors is at play. For the ecological traits of Collembola, this gradient corresponded to an increasing contribution of sensory and locomotory organs, bright color patterns, size and sexual reproduction, all attributes associated with aboveground life under herbaceous cover. Another important, although secondary contrast concerned traits associated with habitats far from soil but that were concealed (corticolous vs. all other habitats). Soil acidity and water did not contribute significantly to trait distribution, at least within the limits of our database.  相似文献   
69.
70.
OBJECTIVES: To describe parental concerns about their child's weight, to determine the proportion of parents taking preventive action to avoid obesity in their children and the predictors of taking preventive action, and to describe the strategies adopted by parents. DESIGN: A cross-sectional survey was conducted. Children's heights and weights were measured, and parents completed a questionnaire that included measures of their own weight status, perceptions of their child's weight, concerns about their child's current weight and future weight as an adolescent and adult, and the strategies used to prevent obesity. SETTING: The study was conducted in Melbourne, Australia. SUBJECTS: A total of 291 families of children aged 5-6 years and 919 families of children aged 10-12 years participated.Results: Eighty-nine per cent of parents of overweight 5-6-year-olds and 63% of parents of overweight 10-12-year-olds were unaware their child was overweight. Seventy-one per cent of parents of overweight 5-6-year-olds and 43% of parents of overweight 10-12-year-olds were not concerned about their child's current weight. Although 31% of parents of 5-6-year-olds and 43% of parents of 10-12-year-olds were taking action to prevent unhealthy weight gain in their children, less-educated parents were less likely to do so. CONCLUSIONS: Public health programmes are required to raise parental recognition of childhood overweight and of related risk behaviours, and to provide parents with practical strategies to prevent unhealthy weight gain in their children.  相似文献   
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