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排序方式: 共有416条查询结果,搜索用时 15 毫秒
51.
From wine to pepper: rotundone, an obscure sesquiterpene, is a potent spicy aroma compound 总被引:1,自引:0,他引:1
Wood C Siebert TE Parker M Capone DL Elsey GM Pollnitz AP Eggers M Meier M Vössing T Widder S Krammer G Sefton MA Herderich MJ 《Journal of agricultural and food chemistry》2008,56(10):3738-3744
An obscure sesquiterpene, rotundone, has been identified as a hitherto unrecognized important aroma impact compound with a strong spicy, peppercorn aroma. Excellent correlations were observed between the concentration of rotundone and the mean 'black pepper' aroma intensity rated by sensory panels for both grape and wine samples, indicating that rotundone is a major contributor to peppery characters in Shiraz grapes and wine (and to a lesser extent in wine of other varieties). Approximately 80% of a sensory panel were very sensitive to the aroma of rotundone (aroma detection threshold levels of 16 ng/L in red wine and 8 ng/L in water). Above these concentrations, these panelists described the spiked samples as more 'peppery' and 'spicy'. However, approximately 20% of panelists could not detect this compound at the highest concentration tested (4000 ng/L), even in water. Thus, the sensory experiences of two consumers enjoying the same glass of Shiraz wine might be very different. Rotundone was found in much higher amounts in other common herbs and spices, especially black and white peppercorns, where it was present at approximately 10000 times the level found in very 'peppery' wine. Rotundone is the first compound found in black or white peppercorns that has a distinctive peppery aroma. Rotundone has an odor activity value in pepper on the order of 50000-250000 and is, on this criterion, by far the most powerful aroma compound yet found in that most important spice. 相似文献
52.
Rose L. Cherry Kryssa L. Johnson Adrien‐Maxence Hespel Karen M. Tobias Daniel A. Ward 《Veterinary ophthalmology》2019,22(3):353-359
A 2‐year‐old, male castrated German shepherd dog was presented to the University of Tennessee Veterinary Medical Center (UTVMC) with periorbital swelling and conjunctival mucopurulent discharge 2 days following removal of a twig from the medial canthus by the owner. Diagnostic imaging was pursued due to the suspicion of a retrobulbar foreign body (FB). A cylindrical FB approximately 3.0 cm in length and 1.0 cm in diameter with concentric rings, suspected to be wooden material, was identified on computed tomography (CT) imaging. An attempt to remove the FB via a stab incision using ultrasound guidance was unsuccessful, and postmanipulation ultrasound confirmed the FB position was unchanged. An exploratory orbitotomy was performed, using the acquired CT images for guidance in locating the FB; however, the FB was not present at the predicted site. The CT imaging was repeated and showed that the FB had migrated rostrally approximately 3.0 cm, compared to the originally acquired study and its same location during attempted ultrasound‐guided removal. A combination of CT‐guided needle placement and contrast injection was then used with repeat imaging in an attempt to better localize the FB and its soft tissue tract. The dog was taken back into the operating room, and the wooden FB was successfully removed. 相似文献
53.
Lucía Dieste‐Prez Tetyda P. Dobak Federico R. Vilaplana Grosso Wilhelmina Bergmann Tijs J. Tobias 《Veterinary radiology & ultrasound》2019,60(2):E15-E19
A 7‐week‐old male pig was presented with signs of a central nervous system disorder. An MRI of the head and cervical spine was performed immediately after euthanasia. The MRI revealed multifocal bilaterally symmetric T2‐weighted hyperintense lesions in the brain and spinal cord, likely due to a toxic metabolic process. Histopathological examination supported the MRI findings and confirmed the diagnosis of edema disease due to Shiga‐like toxin produced by Escherichia coli. This is the first case published of the MRI findings in an edema disease affected pig. 相似文献
54.
55.
Mario Torralba Elisa Oteros-Rozas Gerardo Moreno Tobias Plieninger 《Strength and Conditioning Journal》2018,71(5):549-559
The wood pastures or hardwood rangelands of the southwestern Iberian Peninsula are complex social-ecological systems created from the long-term interaction of society and the landscape. Dehesa, oak woodlands managed for grazing, cropping, and other forms of production, is the most common rangeland system and one of the most distinctive landscapes. Traditionally characterized by multifunctional low-intensity management that enhances a wide range of ecosystem services, current management has shifted from the traditional toward more intensified models. This paper assesses the coproduction of ecosystem services on dehesa properties by exploring the relationship between biophysical and sociocultural factors and dehesa management practices. Based on 42 surveys we analyze 16 quantitative indicators using multivariate techniques. The results indicate that there are four main dehesa types as defined by their characteristics and management: large heterogeneous operations with diverse products; small and homogeneous operations focused on a reduced number of products; medium-large properties focused on crop production; and midsized properties with easy public access. Management is the result of the dynamics of interacting biophysical and sociocultural factors that influence manager priorities and investments. Management decisions group around the degree of multifunctionality of the operation, the relative importance of crop production, the degree of grazing pressure in the system, and how restrictive public access policy is. We find that in the study area, interactions between all the previously mentioned elements covary consistently, generating bundles of ecosystem services associated with each of three management models based on the intensity of management. 相似文献
56.
Lydia J. Tong Whitney Ong Frances Hulst Gabrielle Tobias Kimberly Vinette Herrin Larry Vogelnest 《Journal of Exotic Pet Medicine》2018,27(4):53-60
Iridophores are iridescent cutaneous pigment cells found in reptiles, fish, and amphibians. Neoplasms of iridophores are rarely reported, and little is known about their behaviour, metastatic potential, and prognostic indicators. This paper reports details of the clinical course and pathological findings of metastatic iridophoroma in a veiled chameleon (Chamaeleo calyptratus) and red-barred dragon (Ctenophorus vadnappa). The veiled chameleon presented with a subcutaneous mass on the right lateral elbow and was diagnosed as an iridophoroma on fine needle aspiration. It was otherwise clinically normal. Within 35 days of excision, multiple secondary skin masses developed which were often non-pigmented and required microscopic examination to identify them as iridophoroma metastases. There were in total 54 days between the first detection of the primary mass and end stage, extensive cutaneous and visceral metastatic disease, and there had been no detectable primary mass during routine clinical examination 128 days prior to death. The red-barred dragon presented with a white sub-mandibular mass. While undergoing an excisional biopsy the animal expired, post-mortem examination revealed a cutaneous malignant iridophoroma with tumour cell clusters seen in pulmonary arterial vessels, suggesting that surgical handling of iridophoroma could precipitate the release of circulating tumour cell clusters. This is the first iridophoroma described in a red-barred dragon and the second report of a malignant iridophoroma in a veiled chameleon. Timely detection and careful excision of lizard iridophoroma may be an important factor in clinical outcome. 相似文献
57.
Objective— To evaluate trans-splenic portal scintigraphy (TSPS) and per-rectal portal scintigraphy (PRPS) for diagnosis of congenital portosystemic shunts (CPSS) in dogs, and compare these results with surgical findings.
Study Design— Prospective, randomized cross over clinical trial.
Animals— Dogs (n=42) with suspected CPSS.
Methods— Dogs had TSPS and PRPS 48 hours apart; quantity of radionuclide administered was recorded. Three independent, blinded reviewers evaluated each scintigraphic study for study quality, shunt presence, number, and location of shunt termination (caudal vena cava, azygos vein). All dogs had exploratory celiotomy. Negative scintigraphic findings were confirmed with intraoperative mesenteric portography. Ameroid constrictors were placed on all extrahepatic CPSS, and hepatic biopsies were obtained.
Results— TSPS was 100% sensitive and specific for diagnosis of CPSS and significantly ( P <.05) more likely than PRPS to detect shunt number and termination. Interpretation was consistent between observers, and TSPS required significantly less radionuclide than PRPS.
Conclusion— TSPS was as sensitive as PRPS for detection of shunting vessels, and consistently yielded studies of higher quality, allowing detection of shunt number and location with consistent interpretation among radiologists.
Clinical Relevance— TSPS provides information about shunt number and location, which allows improved surgical planning. Because it requires significantly less radionuclide, TSPS improves safety, allows for more comprehensive patient care, and earlier surgical intervention. 相似文献
Study Design— Prospective, randomized cross over clinical trial.
Animals— Dogs (n=42) with suspected CPSS.
Methods— Dogs had TSPS and PRPS 48 hours apart; quantity of radionuclide administered was recorded. Three independent, blinded reviewers evaluated each scintigraphic study for study quality, shunt presence, number, and location of shunt termination (caudal vena cava, azygos vein). All dogs had exploratory celiotomy. Negative scintigraphic findings were confirmed with intraoperative mesenteric portography. Ameroid constrictors were placed on all extrahepatic CPSS, and hepatic biopsies were obtained.
Results— TSPS was 100% sensitive and specific for diagnosis of CPSS and significantly ( P <.05) more likely than PRPS to detect shunt number and termination. Interpretation was consistent between observers, and TSPS required significantly less radionuclide than PRPS.
Conclusion— TSPS was as sensitive as PRPS for detection of shunting vessels, and consistently yielded studies of higher quality, allowing detection of shunt number and location with consistent interpretation among radiologists.
Clinical Relevance— TSPS provides information about shunt number and location, which allows improved surgical planning. Because it requires significantly less radionuclide, TSPS improves safety, allows for more comprehensive patient care, and earlier surgical intervention. 相似文献
58.
A. Bytnerowicz S. Godzik M. Poth I. Anderson J. Szdzuj C. Tobias S. Macko P. Kubiesa T. Staszewski M. Fenn 《Water, air, and soil pollution》1999,116(1-2):141-150
For the first time concentrations of trace nitrogenous (N) air pollutants, gaseous nitric acid (HNO3), nitrous acid (HNO2), ammonia (NH3), and fine particulate nitrate (NO3) and ammonium (NH4), were measured in the montane forests of southern Poland. Determinations were performed in two forest locations of the Silesian Beskid Mountains in the western range of the Carpathian Mountains, and in an industrial/urban location in Karowice, Poland. The measurements performed in summer 1997 with honeycomb denuder/filter pack systems showed elevated concentrations of the studied pollutants. These findings agree with the low carbon/nitrogen (C/N) ratios and the results of 15N analyses of soil and moss samples. High concentrations of N air pollutants help to explain previously determined high levels of NO3 and NH4 deposition to Norway spruce (Picea abies Karst.) canopies in these mountains. Ambient concentrations of sulfur dioxide (SO2) and ozone (O3) were elevated and potentially phytotoxic. Deficiencies of phosphorus (P) and magnesium (Mg) in Norway spruce foliage were found while concentrations of other nutrients were normal. 相似文献
59.
60.
Pil Birkefeldt Møller Pedersen Kasper Hansen Do Thi Thanh Houng Mark Bayley Tobias Wang 《Aquaculture Research》2014,45(3):427-438
The Asian swamp eel Monopterus albus is normally considered a freshwater species, but can also occasionally be found in brackish water. It is an obligate air‐breather with highly reduced gills, making its osmoregulation physiology interesting because the gills normally represent the primary site of osmoregulation in teleosts. Being a popular fish for human consumption, the swamp eel is cultured extensively in freshwater ponds in the Mekong Delta of Vietnam. However, very little is known about its salinity tolerance, which is becoming topical due to the increasing salt‐water intrusions into tropical deltas. We therefore studied how increased salinity affects survival, growth, blood pressure, heart rate, blood osmolality and plasma ions. All eels survived prolonged exposure to 5 and 10 g L?1, although plasma osmolality increased significantly at 10 g L?1. Further elevation to 15 and 20 g L?1 was associated with significantly elevated mortality, with a corresponding increase in plasma osmolality and ion con‐centrations. Our results show that swamp eels thrive in 0–10 g L?1 with an optimum growth between 0 and 9 g L?1, indicating that utilization of low saline brackish waters for aquaculture is possible. 相似文献