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排序方式: 共有349条查询结果,搜索用时 31 毫秒
1.
OBJECTIVE: To evaluate the applicability of in vivo confocal microscopy (IVCM) in veterinary ophthalmology and analyze the morphology of living, healthy cornea. ANIMALS EXAMINED: Thirty-seven dogs, 34 cats and five birds. PROCEDURE: Various corneal sublayers were visualized in the central region using an in vivo confocal corneal microscope (HRTII/RCM). RESULTS: An investigation method was developed and adapted for use on animals with varying skull forms and eye positions. Real-time images of the epithelial cells, the corneal stroma and the endothelial layer were obtained. The corneal stromal nerve trunks and the subepithelial and basal epithelial nerve plexus were visualized. In dogs, full corneal thickness (FCT) was 585 +/- 79 microm (mean +/- SD) and endothelial cell density (ECD) 3175 +/- 776 cells/mm(2) (mean +/- SD). In cats, FCT was 592 +/- 80 microm and ECD 2846 +/- 403 cells/mm(2). There were no significant differences between canine and feline FCT and ECD and no morphologic differences could be seen between dogs and cats. The bird images revealed a number of structural differences. CONCLUSION: Noninvasive IVCM allows accurate detection of corneal sublayers, corneal pachymetry, endothelial cell density and corneal innervation in various animal species. For clinical usage, patients must be under general anesthesia. The confocal images provided anatomic reference images of various healthy corneal structures in dogs, cats and birds. 相似文献
2.
Buchholz J Wergin M Walt H Gräfe S Bley CR Kaser-Hotz B 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):770-775
BACKGROUND: Squamous cell carcinomas are common skin tumors in cats. We investigated photodynamic therapy (PDT) using a new liposomal photosensitizer as a minimally invasive, effective treatment that can be easily performed while achieving good cosmetic results. AIM: The goal of this study was to assess and describe possible toxicities using a liposomal formulation of the photosensitizer meta-(Tetrahydroxyphenyl)Chlorin (m-THPC) and investigate if favorable pharmacokinetics translate into favorable tumor response and control. ANIMALS: Eighteen client-owned cats with 20 spontaneous cutaneous squamous cell carcinomas were included in the study. METHODS: PDT was performed using a new, liposomal formulation of the photosensitizer. Toxicity, tumor response, and tumor control were evaluated retrospectively. RESULTS: No general adverse effects were observed in cats treated with the new liposomal formulation. Mild local toxicity such as erythema and edema were seen in 15% of the patients. All cats responded to therapy, with a complete response rate of 100%. The overall 1-year control rate was 75%. The tumor recurrence rate was 20% with a median time to recurrence of 172.25 +/-87.1) days. CONCLUSIONS AND CLINICAL IMPORTANCE: A new liposomal photosensitizer was successfully used for squamous cell carcinoma in cats and was well tolerated. There were no systemic adverse effects observed with the liposomal formulation. The favorable pharmacokinetics of the liposomal drug resulted in a favorable tumor response. 相似文献
3.
Overdose and death of both target and non-target species are not uncommon when α–chloralose is used for animal control. Alpha–chloralose appears to depress the central nervous system by having an affect on the GABA-A receptor in a manner similar to ethanol. Recently central administration of oxytocin was shown to block ethanol-induced impairment in rodents. Our study investigates whether IM administration of oxytocin speeds avian recovery from α–chloralose and reduces mortality under simulated field conditions. We found that when injected twice with oxytocin (30 uL/kg) chickens entered α–chloralose narcosis more quickly and showed greater behavioral impairment. When fed the LD50 dose of α–chloralose, repeated injection with oxytocin produced no significant difference in mortality rate or time to death in comparison to the control group. The effects of peripheral oxytocin on female chicks were different than results found previously in cockerels given oxytocin centrally. Oxytocin is not a suitable antidote for α–chloralose overdose during animal capture in the field but instead accentuates α–chloralose narcosis, making capture more likely and efficient. 相似文献
4.
Sven Swedberg 《Water, air, and soil pollution》1995,85(3):1843-1848
Acidification is the most serious threat to the groundwater quality in the province, causing both corrosion on water pipe systems and increased leaching of metals from the ground. The regional groundwater monitoring programme focuses on parameters as pH, alkalinity, sulphate and total aluminium. Sampling is done regularly in 1) natural groundwater springs in the countryside, 2) public water supplies, 3) observation wells in the countryside and 4) observation wells in urban areas.For most of the sites, analysing has been carried out during a time period that is shorter than five years. These sites give valuable information about the general relationship between groundwater acidity and the hydrogeological conditions in the recharge area. Results from regular sampling of public water supplies have been used for studies of time series. The trends indicate that the hydrogeological conditions are of great importance for how the groundwater responds to acid input. In general, surficial groundwater in Quaternary deposits is more sensitive to acidification than groundwater in crystalline bedrock. 相似文献
5.
Nutrient availability in the soil is not only determined by chemical, physical, and micro-biological factors but can be actively influenced by the plant root system. Various components of root activity have been studied in our laboratory during the last 10 years. The major findings are summarized and discussed with special emphasis on root morphology, cation-anion imbalance and proton release, the mechanism of proton release and anion secretion. Large species differences in root morphology were found between red clover and rye-grass. Root morphology was also found to be controlled by environmental and physiological factors. Experimental results obtained with different plant species suggest that proton release by plant roots is not primarily a consequence of excess cation uptake to achieve charge balance in the plant, but rather that active proton extrusion by ATPase activity creates a charge imbalance and a pH gradient which drive nutrient uptake. The pH gradient across the plasmalemma of root cells was also found to be essential for the retention of organic anions by plant roots. 相似文献
6.
7.
E. Buchholz 《Forstwissenschaftliches Centralblatt》1933,55(6):220
Ohne Zusammenfassung 相似文献
8.
Seed of two lucerne varieties, Tuna from Sweden and Nostrale (common) from Italy, multiplied in isolated stand and in the vicinity of each other, was tested in field trials at Perugia (Italy) and at Uppsala (Sweden). In both places distinct differences between the intercrossed populations Tuna (× Nostrale) and Nostrale (× Tuna) were demonstrated. The decrease in winterhardiness as compared with Tuna was very pronounced in the trial at Uppsala. It is concluded that the influence of volunteer lucerne plants in a field or in the vicinity of a seed field is economically very important when seed of a North European variety is produced outside the area of adaptation.
Samenvatting Zaad van twee lucernerassen, Tuna uit Zweden en Nostrale uit Italië, afkomstig van geïsoleerde en van naast elkaar gezaaide velden, werd gebruikt voor veldproeven te Perugia (Italië) en te Uppsala (Zweden). Op beide plaatsen konden duidelijke verschillen tussen de populaties Tuna (x Nostrale) en Nostrale (x Tuna) worden vastgesteld.Opvallend was de achteruitgang in winterhardheid van het in Italië, in de nabijheid van het ras Nostrale, vermeerderde Zweedse ras Tuna.Geconcludeerd wordt dat bij de vermeerdering van Noord-Europese lucernerassen in andere landen (buiten het gebied, waaraan zij zijn aangepast) spontane kruisbestuiving met andere rassen of opslag-planten voorkomen dient te worden.相似文献
9.
Seed of the Swedish lucerne variety U 0615 harvested in a seed field in Israel for four consecutive seasons was tested in field trials in Sweden. Differences in seed yield between plants were demonstrated in Israel — less winter-dormant plants gave more than four times as much seed as winter-dormant plants. On the average Israel-grown seed yielded less in the first cut than Swedish-grown seed, which indicates a decrease in winter-hardiness. The yield was especially reduced in 1962 when winter damage was severe. It is pointed out that varieties may react differently when seed is produced outside the area of adaptation. In a variety with a high degree of heterogeneity, e.g. U 0615, the mode of increase and the stage to be multiplied at southern latitudes should be tested carefully before it is undertaken commercially.Swedish Seed Association, Uppsala 1, Sweden.The Hebrew University, Faculty of Agriculture, Rehovot, Israel. 相似文献
10.
The main purpose of the present study was to investigate whether boar seminal plasma affects the transport of spermatozoa in the genital tract of oestrous pigs or not, with special reference to the sperm transport into the oviducts. Altogether 17 gilts were used in three experiments.Experiment I. In nine gilts one uterine horn was injected surgically with 1010 spermatozoa suspended in seminal plasma and the other uterine horn with 1010 spermatozoa suspended in TESNaK-glucose buffer solution. The sperm deposition was performed under general anaesthesia. The gilts were slaughtered 1–2 or 4–6 h after insemination. The genital tract was removed and the numbers of spermatozoa determined in oviducts and in uterine horns.Experiment II. The insemination doses were prepared exactly as in Experiment I. Approx. 24 h before insemination Polyvinylchloride cannulas were inserted into the uterine lumen of the horns, drawn via the midventral incision at linea alba subcutaneously to cutaneous incisions ventral to the vulva opening. One cannula was placed in each uterine horn. At standing heat the insemination doses were slowly injected through the cannulas. The gilts were slaughtered 1 h after insemination and the numbers of spermatozoa within the genital tract were counted.Experiment III. In three gilts under general anaesthesia the uterine horns were ligated 10 cm from the uterotubal junction. The semen doses (containing 2 × 109 spermatozoa), prepared as in Experiment I, were deposited into the uterine horns anterior to the ligatures through a cannula. The gilts were slaughtered 1 h after insemination, and the numbers of spermatozoa within the oviducts and ligated part of the uterine horns were counted.In all three experiments more spermatozoa were, on average, recovered in the oviducts connected to uterine horns inseminated with spermatozoa suspended in seminal plasma. In Experiments I andII this was the case for 10 of 14 gilts and in Experiment III for all the three gilts. It is therefore suggested that boar seminal plasma pro¬motes sperm transport into the oviduct of oestrous pigs. The back¬ground mechanism for this is discussed. 相似文献