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51.
52.
An 8-year-old mare, with a foal at foot, was inseminated on foal heat with frozen semen, with the resultant pregnancy lost between days 34 and 41. The right ovary developed a large anovulatory follicle that was non-responsive to multiple doses of ovulating agents. The follicle eventually appeared to luteinise, although plasma progesterone concentrations did not reflect this. Another follicle developed, responded to GnRH and resulted in a pregnancy from frozen semen that went to term with a healthy foal. When the mare was examined after foaling, the structure on the right ovary appeared to be a granulosa cell tumour; the left ovary was smaller than normal and non-functional. Surgical removal of the right ovary before increasing photoperiod resulted in a return to function of the left ovary and a pregnancy to frozen semen on the second cycle following removal. Figures showing concentrations of inhibin, progesterone, androstenedione, oestradiol and testosterone are presented for this entire period. Unusual ovarian activity in the mare might be a prelude to the development of a granulosa cell tumour.  相似文献   
53.
A convenient and sensitive method was developed to separate and detect various types of carbohydrates (polyols, mono- and disaccharides, and phosphorylated sugars) simultaneously using high-performance liquid chromatography (HPLC). The method consists of a chromatographic separation on a CarboPac PA1 anion-exchange analytical column followed by pulsed amperometric detection. In a single run (43 min) 13 carbohydrates were readily resolved. Calibration plots were linear over the ranges of 5-25 microM to 1. 0-1.5 mM. The reliable and fast analysis technique, avoiding derivatization steps and long run times, was used to determine the levels of carbohydrates involved in mannitol and trehalose metabolism in the edible mushroom Agaricus bisporus. Moreover, the method was used to study the trehalose phosphorylase reaction.  相似文献   
54.
OBJECTIVE: To investigate the gap between consumer perception and scientific evidence related to health benefits and safety risks from fish consumption. DESIGN: Consumer perceptions from a cross-sectional survey in March 2003 in Belgium were compared with scientific evidence based on a literature review. METHOD: A quota sampling procedure was used with age as quota control variable. Subjects completed a self-administered questionnaire including health benefit beliefs from fish, fish content and effect beliefs for nutrients and harmful substances. SUBJECTS: Adults (n=429), who were the main person responsible for food purchasing in the household (284 women; 145 men), aged 18-83 years, from different regional, education, family size and income groups. RESULTS: Fish is predominantly perceived as a healthy food that reduces risk for coronary heart disease, which corroborates scientific evidence. This perception is stronger among women than among men. In contrast with scientific evidence, 46% of the consumers believe that fish contains dietary fibre, whereas less than one-third is aware that fish contains omega-3 fatty acids and that this nutrient has a positive impact on human health. The gap between perception and evidence is larger among consumers with lower education. In general, consumers are better aware of the content and effect of harmful substances than of nutrients in fish. CONCLUSIONS: Despite conclusive evidence about the content and positive effect of omega-3 fatty acids in fish, related consumer awareness and beliefs are poor and often wrong. This study exemplifies the need for nutrition education and more effective communication about the health benefits of fish consumption.  相似文献   
55.

Purpose

Although archaea play an important role in nutrients cycling, the archaeal community in a reservoir water-level fluctuation zone (WLFZ) remains unclear. An elucidation of archaeal community responding to the environmental variables is essential to understand the nutrients dynamics in WLFZ. This study focused on the response of the archaeal community structure and abundance to the periodic water flooding along an elevation gradient in the WLFZ of the Three Gorges Reservoir.

Materials and methods

Along the elevation gradient (152–175 m) of the study area, soil samples in the beginning and late stages of water flooding were collected to investigate the influence of water flooding on the archaeal community in soil, using quantitative PCR and Illumina high-throughput sequencing approaches.

Results and discussion

An increase of archaeal abundance from 3.8?×?108 to 3.8?×?109 copies (g d.w.s)?1 on average was observed after water flooding. The archaeal abundance was positively correlated with the contents of ammonium, organic matter, and moisture in soil and with the accumulated flooding time. Higher diversity was observed in dry samples (non-flooded soil samples) rather than wet samples (flooded soil samples). The Thaumarchaeota were predominant in most of the dry samples. Interestingly, high proportions of Candidatus Nitrososphaera were observed in the transition zone, while euryarchaeotal methanogens dominated the wet samples. The proportion of methanogens decreased dramatically in the dry samples at higher elevations, which was associated with the decrease of the moisture content and the probably increase of available oxygen in soil.

Conclusions

Archaeal abundance, diversity, and community composition shifted along an elevation gradient and were influenced by water flooding. The increased archaea abundance after water flooding and elevation related community composition and diversity indicated that water flooding was a key dynamic environmental variable in the WLFZ.
  相似文献   
56.
Soil penetration resistance (cone index) varies with water content. The field variation of water content could mask treatment differences. The correction of cone index data to a single water content would help prevent this. We used equations from TableCurve software and from the literature to correct cone indices for differences in soil water contents. Data were taken from two field experiments where cotton (Gossypium hirsutum L.) was grown using conventional and conservation tillage without irrigation, and beans (Phaseolus vulgaris L.) were grown using conventional tillage with microirrigation. Boundary conditions based on hard, dry and soft, wet soils were imposed on the equations. Equations fit the data with coefficients of determination ranging from 0.55 to 0.92 and error mean squares from 1.37 to 6.35. After correction, cone index dependence on water content was reduced. A single-equation correction did not always fit the data across all treatments. Separate corrections, based on treatment, might be required. When corrections required multiple equations, differences may be real or may be a manifestation of the correction differences. In this case, the correction may not be feasible (unless some future work can coordinate different equations and assure a uniform correction).  相似文献   
57.
Gastrointestinal digestion is of major importance in the bioavailability of angiotensin I converting enzyme (ACE) inhibitory peptides, bioactive peptides with possible antihypertensive effects. In this study, the conditions of in vitro gastrointestinal digestion leading to the formation and degradation of ACE inhibitory peptides were investigated for pea and whey protein. In batch experiments, the digestion simulating the physiological conditions sufficed to achieve the highest ACE inhibitory activity, with IC(50) values of 0.076 mg/mL for pea and 0.048 mg/mL for whey protein. The degree of proteolysis did not correlate with the ACE inhibitory activity and was always higher for pea than whey. In a semicontinuous model of gastrointestinal digestion, response surface methodology studied the influence of temperature and incubation time in both the stomach and small intestine phases on the ACE inhibitory activity and degree of proteolysis. For pea protein, a linear model for the degree of proteolysis and a quadratic model for the ACE inhibitory activity could be constituted. Within the model, a maximal degree of proteolysis was observed at the highest temperature and the longest incubation time in the small intestine phase, while maximal ACE inhibitory activity was obtained at the longest incubation times in the stomach and small intestine phase. These results show that ACE inhibitory activity of pea and whey hydrolysates can be controlled by the conditions of in vitro gastrointestinal digestion.  相似文献   
58.
ACE inhibitory activity in enzymatic hydrolysates of insect protein   总被引:1,自引:0,他引:1  
In this paper, ACE inhibitory activity in insect protein hydrolyzed by various enzymes (gastrointestinal proteases, alcalase, and thermolysin) is reported for the first time. Four insects of different insect orders were tested: Spodoptera littoralis (Lepidoptera), Bombyx mori (Lepidoptera), Schistocerca gregaria (Orthoptera), and Bombus terrestris (Hymenoptera). ACE inhibitory activity was measured by two different methods: a spectrophotometric method using FAPGG (2-furanacryloyl-phenylalanyl-glycyl-glycine) as substrate, and an HPLC method using dansyltriglycine (DTG) as substrate. Hydrolysis of the insect protein resulted in an increased ACE inhibitory activity. Overall, the highest ACE inhibitory activity was obtained after gastrointestinal digestion. These results suggest a role for insect protein as antihypertensive component in functional foods and nutraceuticals. Furthermore, the ACE inhibitory activity differed according to the method used. As a consequence, there is a need to standardize methodologies to evaluate ACE inhibitory activity.  相似文献   
59.
Objective To determine reference ranges for healthy yearling farmed saltwater crocodiles by performing routine biochemical and haematological laboratory tests on blood samples.
Design A clinico-pathological study.
Procedure Blood samples were collected from 120 healthy yearlings from four Northern Territory crocodile farms and body weight and length were measured. All animals had been fasted for 2 days before sample collection. Routine biochemical analytes were determined on 120 samples and haematological values determined on 30 samples (from one farm).
Results Reference ranges for biochemical and haemato-logical values were determined for farmed yearling saltwater crocodiles in the Northern Territory.
Conclusion The results were comparable with published reference ranges for other crocodilian species. Other published results of haematological values from saltwater crocodiles were from very young (6-week-old) hatchlings and older (2- to 4-year-old) crocodiles. Differences in values were presumed to be caused by age-related factors.  相似文献   
60.
Two foals from different farms in Virginia were examined for dullness and inappetence in June and October, 1984. They were febrile, icteric and responded initially to treatment with intravenous glucose, and trimethoprim-sulfa but became comatose and died approximately 24 hours after the onset of clinical signs. Each foal was diagnosed as having necrotic hepatitis caused by Bacillus piliformis.  相似文献   
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