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排序方式: 共有354条查询结果,搜索用时 125 毫秒
91.
Federico Soria-Gálvez DVM Francisco Miguel Sánchez-Margallo DVM PhD Idoia Díaz -Güemes Martín-Portugus DVM Francisco Javier Hernández-Hernández MD PhD Luis Javier Ezquerra-Calvo DVM PhD Jesus Usón-Gargallo DVM PhD 《Veterinary radiology & ultrasound》2002,43(5):465-471
This work reports the use of laparoscopic-transducer sonography for the examination of the urinary system in a swine model. Animals underwent a two-phase study. In the first phase, the urinary system was examined using laparoscopic sonography. In the second a partial ureteral obstruction was induced, and sonographic changes were recorded and evaluated. Sonography was used to evaluate kidneys, ureters, and bladder. Anatomic structures were evaluated and the following pathological findings were identified: renal cysts, one polycystic kidney, dilation of the renal pelvis, hydronephrosis, and one perirenal pseudocyst. Where necessary, contrast digital fluoroscopy (excretory urography and retrograde ureteropyelography) was also performed. Laparoscopic sonography mainly is used for evaluation prior to laparoscopic surgery to guide decisions relating to surgery. The quality of the images obtained laparoscopically is superior to that of percutaneous or transabdominal images, because artifacts are reduced and the contact surface of the transducer is placed directly over the study area. Laparoscopic sonography proved highly effective for studying renal and ureteral disorders prior to minimally invasive surgery. 相似文献
92.
Romano Dallai Vittoria Cavallo Luigi Federico Falso Pietro Paolo Fanciulli 《Pedobiologia》2000,44(3-4)
The fine structure of the male reproductive system of Allacma fusca (L.) is described. The system consists of testes, deferent ducts, seminal vesicles, ejaculatory duct and accessory glands. The nature of each part is established. Secretions from the seminal vesicles are stored in the lumen of these organs, then flow into the ejaculatory duct and are used to produce spermatophores. The epithelium of this tract has secretory activity and osmoregulatory function. Secretions and spermatozoa are stored into two distinct parts of the ejaculatory duct, divided by a transverse cuticular septum. 相似文献
93.
Perlo J Demas V Casanova F Meriles CA Reimer J Pines A Blümich B 《Science (New York, N.Y.)》2005,308(5726):1279
We report construction of a portable nuclear magnetic resonance sensor with a single-sided open probe design. The resulting magnetic field inhomogeneity is compensated by a pulse sequence that takes advantage of parallel inhomogeneity in the applied radio frequency field. We can thereby acquire fluorine-19 spectra of liquid fluorocarbons with 8 parts per million resolution, surmounting the long-standing obstacle of obtaining chemical shift information with open probe instruments. 相似文献
94.
95.
Nadia Musco Valeria Maria Morittu Vincenzo Mastellone Anna Antonella Spina Giuseppe Vassalotti Biagio D’Aniello Raffaella Tudisco Federico Infascelli Pietro Lombardi 《Journal of animal physiology and animal nutrition》2021,105(Z1):26-33
A nutritional supplement (Ecotrofin™, by Vetoquinol Italia S.r.l) recommended in ruminants feeding to strengthen the physiological condition and improve digestive performance was tested in 20 pluriparae grazing goats divided in two groups (control and treated) to assess its possible effects on milk yield and quality and to assess eventual adverse effects. Animals from both groups also received 400 g/day of corn meal, and the treated group was supplemented with 20 g/head/day of the nutritional supplement. At the doses suggested by the manufacturer, despite a transient increase after 30 days of supplementation, Ecotrofin™ did not show significant effects on milk yield and, although some changes were found in the fatty acids profile, no significant improvement of MUFA and PUFA, as well as of omega-6:omega-3 ratio and CLA content were seen. Therefore, in our experimental conditions the supplementation of diet with Ecotrofin™ did not appear useful to improve goat's performance. A significant effect on kidney health markers (27 vs. 22.5 for urea and 0.83 vs. 0.76 for creatinine, p < 0.05) suggested a beneficial effect on renal function but, since levels fell in the normal ranges in both groups, such hypothesis would need further studies to be addressed. 相似文献
96.
Francesco Zublena Angela Briganti Chiara De Gennaro Federico Corletto 《Veterinary anaesthesia and analgesia》2021,48(4):563-569
ObjectivesTo describe the technique of performing an ultrasound-guided distal parasternal intercostal block and to determine the distribution of two volumes of methylene blue dye solution injected in canine cadavers.Study designProspective cadaver study.AnimalsA group of seven canine cadavers weighing 12–34 kg.MethodsThe space between the transversus thoracic and the internal intercostal muscles is a virtual cavity. Ultrasound-guided injections in the distal (parasternal) intercostal space were performed using dye solution at 0.05 mL kg–1 in each intercostal space from the second to seventh (LV, low volume, six injections per dog) in one hemithorax, and 0.1 mL kg–1 in the third, fifth and seventh intercostal spaces (HV, high volume, three injections in each dog) on the contralateral side. Anatomical dissection was carried out to describe dye spread characteristics and staining of intercostal nerves.ResultsThe ultrasonographic landmarks for injection were identified in each cadaver. In the LV group the solution was found in every intercostal space (36/36), whereas the HV injection stained six intercostal spaces in two dogs, five in two, and in two dogs the solution was found in four and three spaces, respectively, demonstrating multisegmental distribution. Intrapleural staining was observed after two injections.Conclusions and clinical relevanceUltrasound-guided injection of 0.05 mL kg–1 at the distal intercostal space resulted in staining of the intercostal nerve in all dogs when performed in every space and may be an appropriate alternative to previously reported techniques. A single injection of 0.1 mL kg–1 may anaesthetize more than one intercostal nerve, but not consistently. Clinical investigations are warranted to better characterize and to refine this locoregional technique. 相似文献
97.
Llorach R Tomás-Barberán FA Ferreres F 《Journal of agricultural and food chemistry》2004,52(16):5109-5116
A process to obtain enriched antioxidant phenolic extracts from lettuce (baby, romaine, and iceberg cultivars) and chichory byproducts as a way to valorize these byproducts was developed. Two extraction protocols using water and methanol as solvent were used. Amberlite XAD-2 nonionic polymeric resin was used to purify the extracts. The extraction yield, phenolic content, and phenolic yield were evaluated as well as the antioxidant capacity of the extracts (DPPH, ABTS, and FRAP assays). Baby and romaine lettuce byproducts showed the highest water extract yields [27 and 26 g of freeze-dried extracts/kg of byproduct fresh weight (fw), respectively], whereas baby and iceberg lettuce showed highest methanol extract yields (31 and 23 g of freeze-dried extracts/kg of byproduct fw, respectively). Methanol extraction yielded a raw extract with a high phenolic content, the baby and chicory extracts being the richest with approximately 50 mg of phenolics/g of freeze-dried extract. Regarding the purified extracts, water extraction yielded a higher phenolic content, baby and chicory being also the highest with mean values of approximately 190 and 300 mg of phenolics/g of freeze-dried extract, respectively. Both raw and purified extracts from baby and chicory showed the higher antioxidant contents (DPPH, ABTS, and FRAP assays). The antioxidant capacity was linearly correlated with the phenolic content. The results obtained indicate that lettuce byproducts could be, from the industrial point of view, an interesting and cheap source of antioxidant phenolic extracts to funcionalize foodstuffs. 相似文献
98.
Gil-Izquierdo A Riquelme MT Porras I Ferreres F 《Journal of agricultural and food chemistry》2004,52(2):324-331
The grafting of the rootstock with the lemon tree is an agronomical technique used to improve production and/or quality of the fruit. The interstock has been used with different fruit trees to modulate the tree size, fruit production and quality, and the aging of the tree. The lemon trees grafted with interstocks increase their longevity, lemon production and quality; interstocks are also used to decrease the thickness of the trunk at the grafting point. This enlarging of the trunk provokes a decrease of the sap flow. In our study, "Verna" lemon trees were grafted with interstock between the rootstock and the lemon tree to follow the flavonoid content of the lemon juice. The lemon juice was obtained from the lemons collected of the grafted lemon trees. Two types of rootstocks were used: Citrus aurantium L. and Citrus macrophylla L. Seven interstocks from five cultivars of orange tree, one cultivar of lime tree, and one cultivar of tangerine tree were used. "Verna" lemon trees were also grafted directly to the rootstock. The rootstock was more important agronomic factor than the interstock on the total flavonoid content of lemon juice. The interstock grafting had only a small influence on the flavonoid content of the lemon juice, and it modulated the individual flavonoid content. Citrus aurantium L. rootstock and "Berna" and "Washington Navel" interstocks were the most appropriate to graft in the lemon tree. This interstock grafting technique does not increase the flavonoid content of the lemon juice. Regarding the individual flavonoids, the 6,8-di-C-glucosyl diosmetin was the most affected flavonoid by the type of rootstock used. The interstock used is able to alter the individual quantitative flavonoid order of eriocitrin, diosmin, and hesperidin. In addition, the HPLC-ESI/MS(n) analyses provided the identification of two new flavonoids in the lemon juice: Quercetin 3-O-rutinoside-7-O-glucoside and chrysoeriol 6,8-di-C-glucoside (stellarin-2). The occurrence of apigenin 6,8-di-C-glucoside (vicenin-2), eriodictyol 7-O-rutinoside, 6,8-di-C-glucosyl diosmetin, hesperetin 7-O-rutinoside, homoeriodictyol 7-O-rutinoside and diosmetin 7-O-rutinoside was also confirmed in lemon juice by this technique. 相似文献
99.
Amphibian populations have declined and disappeared in protected and apparently undisturbed areas around the world, especially in montane areas of the tropics. The amphibian chytrid fungus, Batrachochytrium dendrobatidis has been implicated in many of these declines. In Costa Rica most declines occurred in the highlands. We examined an amphibian collection made in Braulio Carrillo National Park in 1986 for the amphibian chytrid fungus B. dendrobatidis, prior to the well documented amphibian declines in Monteverde, along an altitudinal transect from 100 to 2600 m elev. Skin from the pelvic patch of 202 specimens corresponding to 30 species was examined histologically to determine whether the disease was present in the highlands of the park before amphibian populations declined. For comparison, in 2002 we collected and examined 18 specimens of seven species of Eleutherodactylus and Craugastor from two other lowland Caribbean sites. The chytrid fungus was present in almost all altitudes in 1986, including lower areas. The pathogen was also found in both species that later declined and in species that did not do so. We detected chytrid fungus on amphibians collected at almost all altitudes in 1986, including those sampled at 280 m. B. dendrobatidis was abundant in frogs collected in the 2002 survey, and seems to be endemic in most of Costa Rica. More retrospective museum surveys are needed in order to determine whether it can be found in the area before 1986. 相似文献
100.
Bitter flavour of the almond kernel is due to the cyanoglucoside amygdalin and has been the first characteristic considered
in breeding programmes. In such programmes, the seedlings from sweet-kernelled parents were used to study the transmission
of bitterness, which was shown to be a monogenic characteristic, the sweet flavour being dominant. The aim of this work was
to investigate more deeply the inheritance of bitterness in almond, by studying for 2 consecutive years the bitter flavour
in 169 seedlings of 9 families (obtained exclusively for this purpose), one or both parents being bitter-kernelled. With the
exception of the presence of slightly bitter seedlings, the results support the hypothesis of monogenic inheritance of this
trait, the bitter flavour being recessive, although other factors could have a slight influence on the expression of this
characteristic. Heterozygous individuals showed sweet, slightly bitter or year-changeable (sweet-slightly bitter) phenotypes.
Our results demonstrated the possibility of using as parents bitter-kernelled individuals with some outstanding characteristic
desirable for transmission to the progeny, always in combination with a homozygous sweet progenitor. 相似文献